JP2009283433A - High-pressure discharge lamp and lighting system - Google Patents

Abstract

【Task】
Provided are a mercury-free high-pressure discharge lamp having a practically high lamp voltage even when the sealed pressure of xenon is relatively low, and a lighting device using the same.
[Solution]
The high-pressure discharge lamp includes a translucent airtight container 1 having a discharge space 1c therein, a pair of electrodes 2 and 2 disposed in the translucent airtight container so as to be present in the discharge space, a rare gas, and Contains metal halide, metal halide contains at least one halide of thulium (Tm) and holmium (Ho), rare gas is mainly xenon at 1 to 5 atm in terms of room temperature, and does not contain mercury And an ionization medium enclosed in a translucent airtight container.
[Selection] Figure 1

Description

  The present invention relates to a mercury-free high-pressure discharge lamp that essentially does not contain mercury, and an illumination device including the same.

There is known a high-pressure discharge lamp in which a metal halide effective in forming a lamp voltage, such as zinc, which emits less light in the visible region is enclosed in place of mercury and made mercury-free (for example, see Patent Document 1). .) Patent Document 1 includes an input power of 35 W in which a discharge medium of 0.05 cc inner volume, 4.2 mm distance between electrodes, xenon 1 atm, ScI ₃ 0.14 mg, NaI 0.86 mg, FeI ₂ 1 mg is enclosed, An example with a restart voltage of 7 kV is described. Moreover, xenon 5 _atm, ScI 3 _{0.14mg, NaI0.7mg,} input power 35W encapsulating discharge medium GaI 3 0.4 mg, restarting voltage is described embodiment of 8.3KV.

  Regarding the mercury-free high-pressure discharge lamp, in addition to the above, there are a large number of patent documents such as Patent Document 2, but the enclosure pressure of rare gas is widely disclosed up to about 0.1 to 25 atmospheres. Yes. In many cases, the appropriate rare gas pressure is stated to be 5 to 7 atmospheres or more. In this case, the starting high voltage applied to start the high-pressure discharge lamp is 8 kV or more, and xenon is started at 10 atmospheres. The high voltage for use will be 15-20 kV.

JP-A-11-238488 (paragraphs 0216-0230, 0370-0380) WO 2006/046704 Publication

  However, metal halides that are effective in forming a lamp voltage with low emission in the visible region, such as zinc, increase the lamp voltage as the amount of inclusion increases, but the luminous efficiency of the high-pressure discharge lamp increases. There is a problem that the chromaticity deviation increases as the voltage decreases and the discharge becomes unstable.

In contrast, thulium (Tm) and holmium (Ho) halides, unlike other rare earth metal halides, provide a high lamp voltage increase effect in addition to high luminous efficiency. For this reason, the amount of the metal halide for forming the lamp voltage such as ZnI ₂ can be reduced to suppress the above problem, and as a result, high luminous efficiency can be maintained despite the relatively low xenon encapsulation pressure. it can.

  Also, the luminous efficiency is affected to some extent by the lamp voltage. When the starting pressure of the xenon-based rare gas as the starting gas is 1 to 5 atm, the luminous efficiency decreases significantly when the potential gradient between the electrodes falls below 5 V / mm for the rated lamp power 100 W class and 9 V / mm for the 30 W class. Tend to. Therefore, if at least one metal halide of thulium (Tm) and holmium (Ho) is encapsulated as the luminescent metal, the potential gradient between the electrodes can be increased to 100 W class even if the amount of the metal halide encapsulating the lamp voltage is reduced. It is possible to realize a lamp voltage higher than 5 V / mm, preferably 7 V / mm or higher, and higher than 9 V / mm in the 30 W class, preferably 9.5 V / mm or higher. Can be obtained.

  On the other hand, in order to adapt the mercury-free high-pressure discharge lamp to general lighting applications, the E-type base is widely used, so it is necessary to attach this base, but this base has a low withstand voltage. Therefore, it is desirable to be able to start with a high starting voltage of 5 kV or less. However, the conventional mercury-free high-pressure discharge lamp has a starting voltage clearly exceeding 5 kV, as estimated from the above, and thus cannot be compatible with mercury-containing high-pressure discharge lamps, lighting fixtures and wiring using the same. Therefore, a dedicated base is employed, which increases the cost of the lighting system.

  As a result of testing conducted by the present inventor using the same light-transmitting hermetic vessel, electrode and ionization medium as a known mercury-free high-pressure discharge lamp of about 10 atm of xenon, the lamp voltage and Luminous efficiency is low and problems are likely to occur in practice. The problem is particularly noticeable at less than 1 atm. However, it has been confirmed that in a mercury-free high-pressure discharge lamp, if the xenon sealing pressure is 1 to 5 atm, the practical minimum level can be maintained by other lamp parameter designs. In addition, in a mercury-free high-pressure discharge lamp using a translucent ceramic hermetic vessel, it is possible to start at a high voltage for starting up to 5 kV by using appropriate starting auxiliary means up to 5 atm. It has been found that even instant relighting, which was impossible with a conventional ceramic metal halide lamp for general lighting, is possible, and the present invention has been made.

  In addition, when the high-pressure discharge lamp is mercury-free, when halides of rare earth metals such as thulium and holmium are encapsulated as an ionization medium, these halides that remain in a liquid phase state without evaporating are formed of metals that are not rare earth metals. It was found that it is easier to disperse than halides. Therefore, if the rare earth metal halide staying in the liquid phase is attached to a position where the temperature is relatively high, the coldest part temperature can be increased. If the coldest part temperature rises, the lamp voltage becomes higher and the luminous efficiency is expected to rise. Thereby, even if the enclosure ratio is relatively small, an effect of increasing the lamp voltage can be obtained. Therefore, it is possible to reduce the amount of the metal halide encapsulating the lamp voltage corresponding to the amount of the rare earth metal encapsulated, and to suppress adverse effects mainly due to the encapsulation of the lamp voltage forming metal halide.

  Furthermore, if the starting voltage can exceed 5 kV, if the xenon is up to 10 atm, the lamp voltage can be reduced even if the metal halide for forming the lamp voltage is not excessively sealed so as to show its harmful effect. It was found that can be increased to a practical value. As a result, the luminous efficiency is improved and an economical ballast design is possible. In addition, the amount of the metal halide for forming the lamp voltage can be reduced, so that the adverse effects caused by the encapsulation of the metal halide for forming the lamp voltage can be suppressed.

  An object of the present invention is to provide a mercury-free high-pressure discharge lamp having a practically high lamp voltage even when the sealed pressure of a rare gas mainly composed of xenon is relatively low, and an illumination device using the same.

    The high-pressure discharge lamp of the present invention includes a translucent airtight container having a discharge space therein; a pair of electrodes disposed in the translucent airtight container so as to be present in the discharge space; a rare gas and a metal halogen As a metal halide in which the metal halide mainly contributes to light emission, it contains at least one halide of thulium (Tm) and holmium (Ho), and the rare gas is mainly xenon at 1 to 5 atm in terms of room temperature. And an ionization medium enclosed in a light-transmitting hermetic container without containing mercury.

  [Translucent airtight container] The translucent airtight container means an airtight container capable of deriving visible light in a desired wavelength region generated by discharge to the outside. It may be made of any material that is fireproof enough to withstand the normal operating temperatures of. For example, quartz glass or translucent ceramics can be used. However, a light-transmitting hermetic container made of light-transmitting ceramics is particularly suitable in the present invention because the coldest part temperature can be set high, the lamp voltage can be increased, and the luminous efficiency can be improved. . As the translucent ceramic, translucent alumina, yttrium-aluminum-garnet (YAG), yttrium oxide (YOX), and polycrystalline non-oxide such as aluminum nitride (AlN) or single crystal Crystal ceramics or the like can be used. If necessary, it is allowed to form a halogen-resistant or metal-resistant transparent coating on the inner surface of the hermetic container or to modify the inner surface of the translucent hermetic container.

  Moreover, the translucent airtight container has a discharge space inside. And in order to enclose discharge space, the translucent airtight container is provided with the enclosing part. The surrounding portion has an appropriate shape, for example, a spherical shape, an elliptical spherical shape, or a substantially cylindrical shape. Various values can be selected as the volume of the discharge space according to the rated lamp power of the high-pressure discharge lamp, the distance between the electrodes, and the like. For example, in the case of a general illumination lamp, it can be any of 0.1 cc or more and the following depending on the rated lamp power. The maximum inner diameter of the translucent airtight container is 4 to 13 mm for the lamp power 100 W class, 11 mm for the center, 3 to 8 mm for the 35 W class, and 6 mm for the center. It is effective for maintaining high efficiency.

  Further, it is allowed to have a pair of sealing portions at both ends of the surrounding portion. The pair of sealing portions are means for sealing the surrounding portion and supporting the shaft portion of the electrode here and contributing to airtight introduction of current from the lighting circuit to the electrode. It is arrange | positioned at the both ends of the part. When the material of the hermetic container is quartz glass, it is preferable to seal the metal as an appropriate hermetic sealing conduction means inside the sealing part in order to seal the electrode and introduce the current from the lighting circuit to the electrode in a hermetic manner. A structure in which a foil is embedded in an airtight manner can be employed. Note that the sealing metal foil is embedded in the inside of the sealing portion, and the sealing portion serves as a current conducting conductor in cooperation with the sealing portion in order to keep the inside of the enclosure portion of the translucent airtight container airtight. When the translucent airtight container is made of quartz glass, molybdenum (Mo) is the most suitable material. The method of embedding the sealing metal foil in the sealing portion is not particularly limited, but can be appropriately selected and employed from, for example, a reduced pressure sealing method, a pinch sealing method, and a combination thereof.

  On the other hand, as a sealing means when the light-transmitting hermetic container is made of light-transmitting ceramics, for example, frit sealing or frit glass for sealing by pouring frit glass between the light-transmitting ceramics and a current introduction conductor described later. As appropriate, various sealing means such as metal sealing using metal and means for melting the opening to be sealed of the light-transmitting ceramic hermetic container and directly or indirectly sealing the current-introducing conductor can be appropriately used. It can be selectively employed. In order to maintain the lowest temperature of the discharge space formed in the light-transmitting hermetic container at a desired relatively high temperature while maintaining the sealing portion of the light-transmitting hermetic container at a required relatively low temperature. In addition, a small-diameter cylindrical portion communicating with the surrounding portion can be formed. In the case of this structure, the sealing portion is disposed at the end portion of the small diameter cylindrical portion, and is called a capillary between the electrode shaft and the inner surface of the small diameter cylindrical portion by extending the electrode shaft in the small diameter cylindrical portion. A slight gap is formed along the axial direction of the small-diameter cylindrical portion.

  [About Current Introducing Conductor] The current introducing conductor is a means for introducing an electric current into the translucent airtight container, and when the translucent airtight container is composed of a translucent ceramics airtight container, the small diameter cylindrical portion It functions as a means for sealing the translucent ceramic hermetic container together with and supporting the electrodes. Hereinafter, the current introduction conductor in the translucent ceramic hermetic container will be described.

  That is, the current introduction conductor has a distal end connected to and supported by the proximal end portion of the electrode, and the proximal end is exposed to the outside of the translucent ceramic hermetic container. Moreover, the current introduction conductor generally includes a sealing portion and a refractory portion. The sealing portion is a portion that seals the translucent ceramic hermetic container in cooperation with the small-diameter cylindrical portion of the translucent ceramic hermetic container. Therefore, a conductive material having a thermal conductivity coefficient approximated according to the material of the translucent ceramic hermetic container is selected as the sealing portion. For example, sealing metals such as niobium (Nb), tantalum (Ta), titanium (Ti), zirconium (Zr), hafnium (Hf), and vanadium (V) can be used. When the light-transmitting ceramic hermetic container is made of alumina ceramic, niobium and tantalum have the same average thermal expansion coefficient as that of alumina ceramic, and are optimal as a sealing portion. The difference is also small in the case of yttrium oxide and YAG. When aluminum nitride is used for the translucent ceramic hermetic container, zirconium is preferably used for the sealing portion of the current introduction conductor.

  The refractory portion is a portion that supports the electrode by connecting to the tip of the sealing portion. Therefore, a material having an intermediate thermal expansion coefficient with respect to each of the thermal expansion coefficient of the electrode and the thermal expansion coefficient of the sealing portion is used. For example, molybdenum (Mo), tungsten (W) or cermet is used. Can do. However, if necessary, the refractory portion may be omitted and the base end of the electrode may be directly connected to the distal end of the sealing portion. This means that if at least the tip portion of the refractory portion added to the current introduction conductor is made of tungsten, the refractory portion can be used as an electrode. On the contrary, the base end portion of the electrode can be used as a refractory portion, and both are substantially the same.

[A Pair of Electrodes] The pair of electrodes constitutes a high-pressure discharge lamp of a type in which an electrode-type discharge is generated by being sealed in a light-transmitting hermetic container and disposed so as to face the discharge space. The distance between the electrodes formed between the tips of the pair of electrodes is a metal halide mainly having a ionization energy of 8 eV or more and a melting point of 500 ° C. or less as a metal halide for forming a lamp voltage in a general illumination lamp, for example, When ZnI ₂ or the like is encapsulated, the lamp voltage is not as high as when mercury is contained, but the distance between the electrodes is preferably set as follows for the purpose of obtaining a practical lamp voltage.

That is, for example, when the lamp power is 100 W class, the distance between the electrodes is 5 to 38 mm, preferably 6 to 18 mm, more preferably 16 to 18 mm, and 35 W class is also 4 to 22 mm, preferably 4 to 8 mm, more preferably 4 ~ 9mm. Further, if the metal halide for forming a lamp voltage such as ZnI ₂ is sealed in an amount of 0.3 to 4.0 mg / cc, preferably 0.3 to 1.6 mg / cc with respect to the inner volume of the hermetic container, Furthermore, a high desired lamp voltage can be obtained. In addition to the distance between these electrodes, if the maximum inner diameter of the hermetic vessel is set to 4 to 7 mm for the lamp power 100 W class and 3 to 5 mm for the 35 W class, the temperature of the coldest part of the arc tube can be kept high. The luminous efficiency can be kept high.

  In addition, as a constituent material of the electrode, a fire-resistant and conductive metal such as pure tungsten (W), a dopant (for example, scandium (Sc), aluminum (Al), potassium (K), and silicon (Si), etc. It can be formed using doped tungsten containing one or more selected from the group, tritium tungsten containing thorium oxide, rhenium (Re), tungsten-rhenium (W-Re) alloy, or the like.

  Further, in the case of a small lamp, a straight rod-shaped wire or a wire having a large diameter portion at the tip can be used as the electrode. In the case of a medium or large electrode, a coil made of an electrode constituent material can be wound around the tip of the electrode shaft. Note that the pair of electrodes have the same structure when operated with alternating current, but when operated with direct current, the anode generally has a large temperature rise, so that the heat radiation area is larger than the cathode, and therefore the main part should be thick. Can do.

  Furthermore, when the light-transmitting hermetic container is a light-transmitting ceramics hermetic container having a small-diameter cylindrical portion and a small gap called a capillary is formed inside the small-diameter cylindrical portion, the electrode shaft portion can be formed as desired. An electrode mount subcoil such as a refractory metal similar to the electrode, such as tungsten or molybdenum, can be wound around the electrode. The terminal position of the electrode mount subcoil on the side of the surrounding portion should be arranged to extend from the boundary portion between the surrounding portion and the small diameter cylindrical portion into the surrounding portion by 0.05 mm or more, preferably 0.1 mm or more. . In the present invention, in the case of using a translucent ceramic hermetic container in which the boundary portion is not always clear, such as when the boundary between the surrounding portion and the small diameter cylindrical portion is a curved surface, the linear shape of the small diameter cylindrical portion is used. A part where the inner diameter is 1.1 times larger than the inner diameter of the part forming the part is defined as a boundary part between the surrounding part and the small diameter cylindrical part. If the base end of the electrode mount sub-coil is connected to the tip of a refractory part having the same diameter as the electrode shaft part of the current introduction conductor, the base end of the electrode mount subcoil is extended to the periphery of the refractory part and wound. It is preferable.

  Thus, according to the above aspect of the present invention in which the end of the electrode mount subcoil is defined at a predetermined position, the electrode mount subcoil can be optimized in the mercury-free high-pressure discharge lamp. In other words, as one of them, it is possible to effectively suppress the erosion of the inner surface of the small diameter cylindrical portion during the life of the high pressure discharge lamp. In addition, the said erosion tends to occur in a portion closer to the surrounding portion than the center in the axial direction of the small diameter cylindrical portion. When the erosion occurs, a substance generated by the erosion closes the capillary or reacts with the ionization medium to change the composition of the metal halide in the ionization medium. As a result, the luminous flux maintenance factor, chromaticity, and / or lamp voltage of the high-pressure discharge lamp are undesirably changed, which eventually causes a problem of leakage of the translucent ceramic hermetic container.

  As part 2, the residence position of the rare earth metal halide in the capillary extends to a higher temperature position, that is, a terminal position of the electrode mount subcoil that is relatively close to the electrode tip side. Therefore, the coldest part temperature becomes high and the vapor pressure of the enclosed metal halide becomes high. As a result, the lamp voltage is remarkably increased and the luminous efficiency is improved as compared with the case where the terminal end position of the electrode mount subcoil is located in the small-diameter cylindrical portion as in the prior art. On the other hand, in the case of the comparative example having the same specification as that of the above aspect of the present invention except that mercury is enclosed as the lamp voltage forming medium, the residence position of the metal halide may be spread and distributed to the end side. Rather, it showed a tendency to gather at the back part of the capillary, so the effect of increasing the lamp voltage was small.

  It has been found that the following effects obtained by optimizing the electrode mount subcoil are particularly remarkable when the enclosure pressure of the rare gas is 10 atm or less, preferably 5 atm or less in terms of room temperature. When the enclosure pressure of the rare gas exceeds 10 atm, the ratio of the lamp voltage formed by xenon is high, so that the lamp of 35 to 37 V, which is the practical lower limit, is adopted without adopting the above aspect of the present invention. More than voltage can be realized. In addition, when the enclosure pressure of the rare gas exceeds 10 atmospheres, the lamp voltage improvement ratio tends to be lower than when the lamp voltage improvement ratio is 10 atmospheres or less even when the above aspect of the present invention is adopted.

  Furthermore, the heat transfer resistance of the electrode can be increased by disposing the electrode mount subcoil regardless of the end position on the surrounding portion side. As a result, the temperature of the sealing portion formed at the end of the small diameter cylindrical portion of the translucent ceramic hermetic container can be easily lowered to a desired level. The reaction between the metal halide and the electrode mount can be suppressed, and the high-pressure discharge lamp can have a long life. The electrode mount is an assembly of an electrode and a current introduction conductor. Further, by disposing the electrode mount subcoil, the metal halide tends to stay in the capillary, and the coldest part can be easily formed as desired.

  In addition, in the aspect which arrange | positions an electrode mount subcoil to an electrode, the average clearance gap of the capillary formed between an electrode mount subcoil and the inner surface of a small diameter cylinder part is the range of 0.01-0.15 mm. Is preferred.

  [Ionization Medium] The ionization medium contains a metal halide and a rare gas, but does not contain mercury. In the present invention, the metal halide contains at least one of thulium (Tm) and holmium (Ho). The rare gas is mainly xenon and has an atmosphere pressure of 1 to 5 atmospheres when the ambient temperature is 25 ° C. This will be described in detail below.

    First, the metal halide will be described. In the present invention, at least one of thulium (Tm) and holmium (Ho) is mainly used as a metal halide that contributes to light emission. The metal halide is not only a metal halide mainly contributing to light emission, but preferably a metal halide having an ionization energy of 8 eV or more and a melting point of 500 ° C. or less is mainly used for forming a lamp voltage. Encapsulated as a halide.

  Thulium (Tm) emits a number of emission line spectra near the peak wavelength of the luminous characteristic curve at the time of discharge, and its emission peak coincides with the peak of the luminous efficiency curve, so it is extremely effective in improving luminous efficiency. Light emitting metal. However, these metal halides are not only metal halides that mainly contribute to light emission, but also have an effect of increasing the lamp voltage in a mercury-free manner. For this reason, it is possible to reduce the amount of metal halide mainly for forming the lamp voltage. As a result, it is possible to avoid the adverse effects (increased color deviation and decreased luminous efficiency) which are mainly caused by the relatively excessive amount of the metal halide for forming the lamp voltage. Holmium also has properties similar to those described above for thulium.

  Note that the metal that mainly contributes to light emission is a metal that clearly contributes to light emission as a high-pressure discharge lamp, and it does not matter whether the lamp voltage is formed or not. Therefore, the metal that contributes to light emission is also a light-emitting metal excluding the metal halide for forming a lamp voltage, which will be described later. However, thulium and holmium correspond to metals that contribute to light emission because they have a large amount of light emission in the visible region as described above, but also have a lamp voltage forming action as described above.

  In addition, it contains at least one halide of thulium (Tm) and holmium (Ho) as a main component of a metal halide that mainly contributes to light emission, and 1 to 3 when the xenon-based rare gas is an ambient temperature of 25 ° C. In a preferred embodiment of the present invention in which the atmospheric pressure is sealed, the chromaticity deviation duv. The change width is preferably 0.0150 or less. Further, in this aspect, since the amount of emission in the blue region is significantly smaller than that in the case where the sealed pressure of the rare gas mainly composed of xenon is higher than the above, the light emission efficiency is increased and the emission in the blue region is lower than that in the case of lower than the above. Therefore, the chromaticity deviation does not deteriorate beyond a practical level.

  Further, in the present invention, when at least one of thulium (Tm) and holmium (Ho) halides is encapsulated, the metal halide for mainly forming a lamp voltage, which will be described later, is excluded. In general, the expected effect can be obtained by enclosing 10% by mass or more of the total amount of halide. That is, if 10% by mass or more is enclosed, for example, the end position of the electrode mount subcoil on the side of the surrounding portion extends as described above to 0.05 mm or more, preferably 0.1 mm or more into the surrounding portion. In the aspect of the invention, since the site where the rare earth metal halide is attached to the electrode mount subcoil extends to the high temperature region on the discharge space side, the effect of optimizing the electrode mount subcoil is generated and the lamp voltage is increased. Therefore, it is easy to obtain a practical lamp voltage without relying on the inclusion of a halide for forming the lamp voltage, and thus without the disadvantages associated with the inclusion of the halide. In addition, the spread of the adhesion site of the rare earth metal halide is a peculiar phenomenon in the case of mercury-free, and may reach the inner surface of the surrounding portion depending on the case.

  Further, in another aspect or in addition to the above-described aspect, since the enclosure pressure of the xenon-based rare gas at a temperature of 25 ° C. is more than 5 atm. A practical lamp voltage can be obtained even in an embodiment in which the encapsulation ratio of at least one of thulium (Tm) and holmium (Ho) halides is 10% by mass or more and less than 35% by mass.

  The effect of the above-described electrode coil optimization appears particularly prominent when the enclosed pressure of the xenon-based rare gas is 10 atmospheres or less, preferably 5 atmospheres or less. The effect shows a decreasing trend.

Furthermore, if at least one of thulium (Tm) and holmium (Ho) halides is contained in an amount of 35% by mass or more based on the total amount of metal halides mainly contributing to light emission, thulium (Tm) and Holmium (Ho) is suitable in the present invention because it exhibits the effect of sufficiently increasing the lamp voltage to the practical range and high luminous efficiency is obtained. For this reason, even if the amount of the metal halide for forming the lamp voltage such as ZnI ₂ is reduced to, for example, 1/5 of the conventional case, a lamp voltage equivalent to that before the amount of reduction can be obtained. it can. Since the color deviation increases as the amount of the metal halide for forming the lamp voltage increases, the color deviation is remarkably improved by decreasing the amount of the metal halide for forming the lamp voltage.

  Furthermore, if the total of thulium (Tm) and holmium (Ho) halides is contained in an amount of 50% by mass or more based on the total amount of metal halides that mainly contribute to light emission, higher lamp voltage and higher light emission. Since efficiency can be obtained, it is even more preferable. However, when the encapsulation ratio exceeds 80% by mass, the ratio at which metal halides other than thulium (Tm) and holmium (Ho) can be encapsulated is correspondingly reduced. As a result, desired white light emission cannot be obtained, which is not preferable for the purpose of obtaining white light emission. Further, when the enclosure ratio of thulium (Tm) and holmium (Ho) halide is in the range of 50 to 70% by mass, particularly high luminous efficiency is obtained.

  It is permissible to add thallium (Tl) if desired. Thallium can be encapsulated in the form of thallium halide or metal thallium as a minor component of the halide in the ionization medium that mainly contributes to light emission. However, in the present invention mainly containing at least one halide of thulium (Tm) and holmium (Ho) as a metal halide that mainly contributes to light emission, the amount enclosed is converted to thallium iodide (TlI). The value is preferably regulated to 0 to 0.8 mg / cc, preferably 0 to 0.2 mg / cc with respect to the inner volume of the translucent airtight container. Thereby, it can suppress effectively that blue light emission suppression arises. When a thallium (Tl) halide or metal thallium is enclosed, the green light emission of thallium (Tl) is added to at least one kind of light emission of thulium (Tm) and holmium (Ho). Becomes higher.

  In addition to the purpose of obtaining white light emission, other metal halides other than those described above can be appropriately and selectively added for the purpose of, for example, adjusting the chromaticity of light emission or increasing the light emission efficiency. Hereinafter, main examples in the case of adding other metal halides will be described.

  When encapsulating a halide of a metal that mainly emits an alkali metal such as sodium (Na), the amount of the encapsulated metal is controlled to 30% by mass or less based on the total amount of the halide of the mainly emitting metal. The voltage can be kept high. Further, when the content is 25% by mass or less, in the present invention, the emission of alkali metal is weakened, and on the contrary, the emission ratio of the rare earth metal is increased, so that the average color rendering index Ra is increased.

  Further, when various conditions such as light emission characteristics and manufacturability are allowed, the reduction of lamp voltage is suppressed to a minimum by encapsulating the alkali metal within a range of less than 3% by weight, while the light emission efficiency is improved. It is possible to improve lamp life and light color adjustment, in particular, color deviation. In view of the above, the encapsulation of the alkali metal halide is allowed within a range in which a required lamp voltage can be secured. The enclosed amount is preferably 2 to 8% by mass, more preferably 3 to 7% by mass, and still more preferably 4 to 6% by mass. Moreover, as an alkali metal other than sodium, one or a plurality of groups of cesium (Cs) and lithium (Li) can be selectively encapsulated.

  As a rare earth metal halide, when at least one of thulium (Tm) and holmium (Ho) is a main component, praseodymium (Pr), cerium (Ce), dysprosium (Dy) and samarium (Sm) are used as accessory components. One or more halides can be added. The rare earth metal is useful as a luminescent metal next to thulium halide and holmium halide, and is allowed to be encapsulated at an encapsulation ratio as an accessory component. Note that any of the rare earth metals has an innumerable emission line spectrum near the peak wavelength of the visibility characteristic curve, and thus can contribute to an improvement in luminous efficiency.

  Indium (In) halide is allowed to be selectively encapsulated as a subcomponent for the purpose of obtaining a desired color rendering property and / or color temperature.

  As the halogen forming each of the above halides, iodine is suitable because it has moderate reactivity, but it may be either bromine or chlorine as desired, and any of iodine, bromine and chlorine is desirable. Two or more of these may be used.

  Next, the metal halide for forming the lamp voltage will be mainly described. In the present invention, the metal halide mainly for forming the lamp voltage often includes a metal halide having an ionization energy of 8 eV or more and a melting point of 500 ° C. or less. In addition, although a specific metal is mentioned later, there exists a halide of zinc (Zn), aluminum (Al), manganese (Mn), etc. The metal halide for forming the lamp voltage is a buffer that contributes to forming the lamp voltage, but means that visible light is allowed to be generated by the metal constituting the buffer. However, there is a common feature that the amount of visible light generated is obviously smaller than that of metal halides that mainly contribute to light emission.

  In the present invention, since at least one of thulium halide and holmium halide is sealed at a predetermined ratio and the xenon main body is sealed at 3 to 5 atm, a desired lamp voltage is formed. It is not necessary to enclose the halide for use. However, in the present invention, the amount of at least one of thulium halide and holmium halide to be enclosed is not particularly limited, and the enclosure pressure of the xenon-based rare gas at an ambient temperature of 25 ° C. is in the range of 1 to 5 atm. Therefore, if necessary to form a potential gradient of 7 V / mm or more between a pair of electrodes, it is permitted to enclose a required amount of a metal halide mainly for forming a lamp voltage. In this case, it is preferable to enclose within the range of 0.3-4 mg / cc with respect to the internal volume of a translucent airtight container.

  In addition, the metal halide for forming the lamp voltage has a higher vapor pressure than the above-mentioned metal halide mainly contributing to light emission enclosed in the light-transmitting hermetic container in the present invention. It has the effect of mainly determining the voltage. Note that “the vapor pressure is high” means that the vapor pressure during lighting is high, but it is not necessary to be too high like mercury, and preferably the pressure in the airtight container during lighting is about 5 atm or less. is there. Therefore, it is not limited to a specific metal halide as long as the above conditions are satisfied.

The metal halide that forms the lamp voltage is, for example, magnesium (Mg), iron (Fe), cobalt (Co), chromium (Cr), zinc (Zn), nickel (Ni), manganese (Mn), aluminum ( One or more metals selected from the group consisting of Al), antimony (Sb), beryllium (Be), rhenium (Re), gallium (Ga), titanium (Ti), zirconium (Zr) and hafnium (Hf) The halide can be used as a main component. Most of them have a vapor pressure lower than that of mercury, and the adjustment range of the lamp voltage is narrower than that of mercury. However, the adjustment range of the lamp voltage can be expanded by mixing and enclosing a plurality of these as required. For example, when AlI ₃ is in an incompletely evaporated state and a desired lamp voltage is not obtained, the lamp voltage does not change even if AlI ₃ is added.

On the other hand, if ZnI ₂ is added instead of adding AlI ₃ , the lamp voltage corresponding to the action of ZnI ₂ is added, so that the lamp voltage can be increased. Furthermore, if another halide for forming a lamp voltage is added, a higher lamp voltage can be obtained.

  Furthermore, the halide for forming the lamp voltage is a metal halide that hardly emits light in the visible region as compared with the above-described halide metal that emits light mainly enclosed in the light-transmitting hermetic container. The phrase “difficult to emit light in the visible region compared to the metal of the halide” does not mean that light emission of visible light is small in an absolute sense, but a relative meaning. For sure, Fe and Ni emit more in the ultraviolet region than in the visible region, but Ti, Al, Zn and the like emit more in the visible region. Therefore, when these metals that emit a lot of light in the visible region are caused to emit light alone, energy is concentrated on the metal, so that there is a lot of light in the visible region. Among the lamp voltage forming halides, iron (Fe) and nickel (Ni) emit much in the ultraviolet region, but titanium (Ti), aluminum (Al), zinc (Zn), etc. emit light alone. Emits much light in the visible light range. However, the lamp voltage forming metal such as titanium (Ti), aluminum (Al), and zinc (Zn) mainly emits light such as thulium (Tm) and holmium (Ho) whose energy level is necessary to emit light. Higher than the energy level required to emit light from the metal halide. For this reason, when the high pressure discharge lamp is turned on by enclosing both together, the light emission by the metal of the halide which mainly contributes to the light emission having a low energy level becomes relatively dominant, and the halide for forming the lamp voltage The light emitted by the metal is reduced.

  Therefore, the metal halide for forming the lamp voltage is not prohibited from emitting visible light by the metal, but has a small effect on the total visible light emitted by the discharge lamp and has little influence.

  Next, the rare gas will be described. As described above, the rare gas is filled with xenon (Xe) main body of 1 to 5 atm when the ambient temperature is 25 ° C. The reason why the xenon-based rare gas filling pressure is specified as described above is mainly necessary to reduce the starting voltage and to obtain compatibility with high-pressure discharge lamps, lighting fixtures and wiring for general lighting containing mercury. This is because it is a premise. However, it is preferably 1 to 3 atm.

  However, when the starting voltage does not have to be 5 kV or less, the sealed pressure of the xenon-based rare gas can be set high to 10 atm or less. Within this range, for example, the effect of increasing the lamp voltage by optimizing the electrode mount subcoil can be obtained in a practical sense. As a result, the lamp voltage can be increased without deteriorating the light emission characteristics.

  Xenon-based means that the volume of xenon may be 80% or more. Examples of rare gases that can be mixed with xenon include argon (Ar), krypton (Kr), and neon (Ne).

  Explain about mercury. The present invention is a mercury-free high pressure discharge lamp and therefore does not enclose mercury.

  [Other Configurations] In the present invention, if desired, a part or all of the following configurations are included in at least the arc tube and a starting assistant described later.

  1. (Outer tube) An outer tube is a means for accommodating the arc tube provided with the translucent airtight container, a pair of electrodes and an ionization medium described above. Further, if necessary, in addition to the arc tube, it is possible to accommodate a starting assisting unit described later.

  In addition, the outer tube can have any desired shape and size. However, in order to facilitate compatibility with a high-pressure discharge lamp for general illumination containing mercury, the outer tube has the same shape and size. Allow that. Further, if the inside of the outer tube is hermetically sealed with respect to the outside and is kept in a vacuum or a reduced pressure state, the coldest part temperature of the arc tube can be increased to increase the luminous efficiency. When making it airtight with respect to external air, it can replace with external air as needed, and can enclose inert gas, such as argon and nitrogen. However, the arc tube material may be communicated with the outside air if desired. Furthermore, the outer tube can be formed using a translucent material such as quartz glass, hard glass, or soft glass.

  Further, a base is attached to one end side of the outer tube so as to be attached to the socket. Since the base as a high pressure discharge lamp for general illumination is a screw type (E type) base, it is preferable to use this screw type (E type) base in the present invention.

  2. (Starting auxiliary means) The starting auxiliary means is disposed in the outer tube and discharges the ionized medium in the arc tube when a high starting voltage is applied between a pair of electrodes disposed in the translucent airtight container. Is a means for assisting the start-up so as to start. In the present invention, it is possible to start by applying a starting high voltage of 5 kV or less between the pair of electrodes of the arc tube by providing the starting assisting means. In addition, for example, at least one of a known proximity conductor and ultraviolet radiation means is allowed to be used as the starting assisting means. Further, if desired, other known starting aids such as a starter can be used in combination.

  The proximity conductor is made of a heat-resistant conductor, and on the outer surface side of the translucent airtight container, the proximal end is electrically connected to one of the pair of electrodes, and the distal end is connected to the other electrode on the wall surface of the translucent airtight container And is disposed at a position facing the translucent airtight container close to the outer surface. The heat-resistant conductor is, for example, a conductive metal such as molybdenum, stainless steel, nickel, or an alloy thereof, and is attached to a conductor called a trigger wire or an outer surface of a light-transmitting airtight container. It is allowed to be a conductive film mainly composed of a conductive metal.

  Thus, the proximity conductor is arranged so as to form a large potential gradient at a short distance between the tip and the other electrode facing the tip. By providing the proximity conductor, the high-pressure discharge lamp is easily broken down when a high voltage for starting is applied, and the starting is promoted. When the high-pressure discharge lamp is started and glow discharge is generated in the arc tube, and further transferred to arc discharge, the adjacent conductor is short-circuited by the arc tube, so that lighting is not hindered.

  If the ultraviolet radiation means is connected in parallel to the arc tube, and is disposed near at least one electrode of the arc tube, and emits ultraviolet rays in the vicinity of the electrode approaching when starting the high-pressure discharge lamp, Any other configuration is not required. For example, an ultraviolet radiation discharge tube or a glow discharge lighting tube called an ultraviolet enhancer is allowed. In either case, the discharge vessel has ultraviolet transparency, and ultraviolet rays generated when discharge occurs inside can be led out to the outside of the discharge vessel.

  Thus, the ultraviolet radiation means operates when the high-pressure discharge lamp is started to generate ultraviolet light and irradiates it in the vicinity of one electrode of the arc tube. As a result, electrons are emitted from the electrode and, in some cases, the inner surface of the light-transmitting hermetic vessel by photoelectric effect to become initial electrons, which excites the ionization medium inside the light-transmitting hermetic vessel and accelerates the start of the high-pressure discharge lamp. Is done. When the high-pressure discharge lamp is started, the ultraviolet radiation means is not applied with a high voltage due to the arc generated in the arc tube, so that it does not hinder lighting.

  The starter is configured with a switching means such as a glow starter, bimetal switch, or non-linear capacitor, and is disposed in the outer tube, and performs a rapid switching operation when the power is turned on. A high starting voltage is applied between the electrodes of the arc tube to facilitate starting of the metal vapor discharge lamp.

  In the present invention, when the sealing pressure of the rare gas of the ionization medium is relatively low within the allowable range, the starting voltage is relatively lowered. Therefore, even if only the proximity conductor is provided, the starting voltage is 5 kV or less. It can be started by applying a voltage. On the other hand, when the noble gas filling pressure is relatively high within the allowable range, the starting voltage is relatively high. Therefore, if both the proximity conductor and the ultraviolet radiation means are used in combination, the starting voltage is 5 kV or less. It can be started by applying a voltage. In addition to the proximity conductor and the ultraviolet radiation means, it is allowed to use other start assisting means together if desired.

  3. (Starting high voltage applying means) When the high pressure discharge lamp of the present invention is provided with a starting auxiliary means, even when the starting high voltage is 5 kV or less, it can be applied to start the high pressure discharge lamp. Of course, the high-pressure discharge lamp of the present invention can be lit by applying a high starting voltage exceeding 5 kV. As a starting high voltage applying means, for example, a high voltage pulse generator called an igniter is combined with a high pressure discharge lamp, and a high voltage pulse generated from the high voltage pulse lamp is applied and a high voltage discharge lamp is turned on using a ballast. In so doing, any of the modes in which a so-called kick voltage generated therefrom is applied to the arc tube from the outside of the high-pressure discharge lamp may be used. Further, the starting high voltage generator such as an igniter may be in any of an aspect in which it is accommodated in a case of a ballast, an aspect in which it is accommodated in a base, and an aspect in which it is accommodated in an outer tube. In order to generate a kick voltage, it is allowed to arrange a start switch such as a heat responsive switch or a voltage responsive switch inside the outer tube of the high-pressure discharge lamp, if desired.

  4). (Rated lamp power of high-pressure discharge lamp) In the present invention, the rated lamp power of the high-pressure discharge lamp can be freely set over a wide range. However, it is preferably about 30 to 250 W. The use of the high-pressure discharge lamp is allowed to be diverse, but is preferably for general illumination. Accordingly, a translucent hermetic container having an appropriate shape and size according to the rated lamp power and application, an interelectrode distance of an appropriate value, and an ionization medium having an appropriate encapsulation ratio of at least one of thulium and holmium and its encapsulation The amount and the enclosed pressure within the allowable range mainly composed of xenon can be appropriately selected.

5. (Relationship between tube wall load and translucent airtight container temperature) In the present invention, the tube wall load of the translucent airtight container of the high-pressure discharge lamp is not particularly limited, but is preferably 22 to 35 W / cm ² . . The tube wall load is a value obtained by dividing the lamp power by the inner area of the enclosure that surrounds the discharge space of the translucent airtight container. Even with such a tube wall load, when the enclosure pressure of the rare gas is 1 to 3 atm when the ambient temperature is 25 ° C., 0.2 to 20 when the enclosure pressure of the rare gas is 25 ° C. It has been found that the highest temperature of the translucent airtight container becomes lower in the range of atmospheric pressure.

  Therefore, the high-pressure discharge lamp of the present invention can maintain the operating temperature of the surrounding portion and the small-diameter cylindrical portion of the translucent airtight container at a value other than the rare gas filling pressure and lower than the case of the equivalent tube wall load. it can. As a result, the high-pressure discharge lamp has a long life. An example of the operating temperature difference is as follows. That is, the operating temperature in the embodiment of the high-pressure discharge lamp of the present invention in which the enclosed pressure of xenon is 2.4 atm and the lamp power is 30 W is when the temperature at the center of the enclosure is the enclosed pressure of xenon is 25 ° C. The operating temperature is 90 ° C. lower than the operating temperature of the comparative example having the same specifications as the high-pressure discharge lamp of the present invention except for 16 atmospheres.

  6). (Protection means at the time of arc tube rupture) In the present invention, a known protection means can be used in order to protect the fragments from being scattered when the arc tube of the high pressure discharge lamp is ruptured. For example, a quartz glass cylinder called a shroud is held in the outer tube so as to surround the arc tube mainly around the surrounding portion of the translucent airtight container. Alternatively, the entire outer tube can be further surrounded by a protective glass tube from the outside. Furthermore, in order to satisfy the required explosion-proof performance when the arc tube ruptures, it is possible to increase the thickness of the glass as desired, or to wrap a string member made of metal or inorganic fiber for reinforcement around the outside of the shroud. it can.

  [Other Characteristics of High Pressure Discharge Lamp Obtained by the Present Invention] The following characteristics can be imparted to the high pressure discharge lamp obtained by the present invention.

  1. (Lighting direction) In the high-pressure discharge lamp of the present invention, the xenon-based rare gas is 1 to 5 atm, preferably 1 to 3 atm when the ambient temperature is 25 ° C., and is mainly a metal for forming a lamp voltage. Even in a mode in which the halide is enclosed, the amount of the enclosure can be reduced, so that the arc is less likely to be bent, so that the life is prolonged even when horizontal lighting is performed. Vertical lighting is also possible.

  2. (Flux rise) The high-pressure discharge lamp of the present invention has a lamp power of 30 to 70 W class and the rise of 50% of the light flux is within one minute, and the lamp power is 100 to 250 W class and within two minutes.

  3. (Ramp voltage rise) The high-pressure discharge lamp of the present invention has a lamp power of 30 to 70 W class and the rise to a lamp voltage of 50% is within 1 minute, and the lamp power of 100 to 250 W class is also within 2 minutes.

  4). (Change in chromaticity at the time of rising) The high-pressure discharge lamp of the present invention has a change width of chromaticity at the time of rising of duv. Good -0.020 to +0.015.

  5). (Dimming) Since the high-pressure discharge lamp of the present invention is mercury-free, dimming is possible. Further, at least one of thulium and holmium is a main component of a metal halide that mainly emits light, and the enclosure pressure of a rare gas mainly composed of xenon is 1 to 3 atm when the ambient temperature is 25 ° C. Change in color temperature is reduced.

  6). (Arc transition time) In the high-pressure discharge lamp of the present invention, the arc transition time transition time at start-up and instantaneous relighting is shortened by sealing mercury-free rare gas mainly containing xenon at 1 to 3 atm. As a result, electrode wear is reduced and blackening of the translucent airtight container is reduced, so that the high-pressure discharge lamp has a long life.

  7. (Glow discharge time) The high-pressure discharge lamp of the present invention is mercury-free and has a pressure of 1 to 3 atm when the atmospheric pressure of the xenon-based rare gas is 25 ° C. The glow discharge time is shortened. As a result, electrode wear is reduced and blackening of the translucent airtight container is reduced, so that the high-pressure discharge lamp has a long life.

  [On the lighting device of the high-pressure discharge lamp] In the present invention, the lighting device of the high-pressure discharge lamp may be any of a ballast mainly composed of an iron core and a coil and an electronic lighting device. The high-pressure discharge lamp of the present invention uses a lighting device with an open circuit voltage of 260 V (or 290 V) or higher, so that it can be reliably transferred from glow discharge to arc discharge after dielectric breakdown at start-up, and can be restarted at high temperature. It is. Moreover, if the enclosure pressure of the rare gas is set to 2 atm or less, a plurality of start assisting means are arranged in combination, or the configuration of the start assisting means is optimized, a lighting device with an open circuit voltage of 240 V or less is provided. Even when used, starting and instantaneous restart are possible.

  The lighting device is composed of a lighting circuit for energizing and lighting the high pressure discharge lamp, and a starting high voltage generator for starting the high pressure discharge lamp by generating a starting high voltage of 5 kV or less. Can do. In the present invention, various known lighting circuits can be employed as the lighting circuit. For example, a circuit configuration such as a full-bridge inverter circuit or a half-bridge inverter circuit, preferably a rectangular wave AC generating circuit that generates a rectangular AC voltage having a low frequency can be used. Alternatively or in addition, a DC voltage conversion circuit such as a step-up chopper or step-down chopper can be attached to the DC power supply of the inverter circuit for power supply voltage adjustment and / or active filter function, or these circuits can be lit by DC It can be used as a device.

  [About Lighting Device] The lighting device of the present invention includes a lighting device body; a high-pressure discharge lamp according to any one of claims 1 to 3 disposed in the lighting device body; and a lighting device for lighting the high-pressure discharge lamp. It is characterized by having; and.

  In the present invention, the lighting device is a concept including a device using the high-pressure discharge lamp of the present invention as a light source, such as a lighting fixture, a marker lamp, an indicator lamp, a photochemical reaction device, and the like. In addition, the lighting device main body refers to all of the remainder excluding the high-pressure discharge lamp from the lighting device.

  According to the present invention, by containing at least one halide of thulium and holmium as a metal halide mainly emitting light, and by enclosing a rare gas mainly composed of 1 to 5 atm when the ambient temperature is 25 ° C., The lamp voltage is increased, the luminous efficiency is improved, and a practical mercury-free high-pressure discharge lamp can be provided.

  Further, according to the aspect in which the encapsulation ratio of at least one halide of thulium and holmium to the total amount of the metal halide mainly contributing to light emission is 10% by mass or more, the effect of electrode mount subcoil optimization and / or xenon According to the embodiment in which the main rare gas is sealed at a pressure of more than 5 atm and less than 10 atm, the lamp voltage can be increased without deteriorating the lamp characteristics, thereby improving the luminous efficiency and the ballast design. A mercury-free high-pressure discharge lamp can be provided.

  Furthermore, according to the aspect in which the encapsulation ratio of at least one of the thulium and holmium halides to the total amount of the metal halide that mainly contributes to light emission is 35% by mass or more, in addition, the at least one halide of thulium and holmium It is possible to provide a mercury-free high-pressure discharge lamp that exhibits an effect of sufficiently increasing the lamp voltage to a practical range and that can obtain high luminous efficiency.

  Furthermore, according to the aspect including a metal halide having an ionization energy of 8 eV or more and a melting point of 500 ° C. or less, a mercury-free high-pressure discharge lamp having a higher lamp voltage due to the addition of the metal halide. Can be provided.

  Furthermore, when the enclosed pressure of the rare gas mainly composed of xenon is 10 atmospheres or less, preferably 5 atmospheres or less in terms of room temperature, the end of the electrode mount subcoil on the enclosure portion side of the translucent ceramic hermetic container has a small diameter. According to the aspect in which 0.05 mm or more extends from the boundary portion between the cylindrical portion and the surrounding portion into the surrounding portion, the electrode mount subcoil is optimized and the attachment portion of the rare earth metal halide to the electrode mount subcoil is optimized. Therefore, it is possible to provide a mercury-free high-pressure discharge lamp in which the vapor pressure of the rare earth metal halide is increased, and as a result, the lamp voltage is significantly increased.

  Furthermore, according to the aspect provided with the outer tube and the starting auxiliary means, in addition, it is possible to start reliably even when the starting high voltage applied between the pair of electrodes is 5 kV or less, and in which mercury is enclosed. A mercury-free high-pressure discharge lamp compatible with a high-pressure discharge lamp for illumination can be provided.

  Furthermore, the illumination device provided with the high-pressure discharge lamp of the present invention can provide an illumination device that exhibits the above effects.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.

  FIG. 1 is a cross-sectional view showing a first embodiment for carrying out the high-pressure discharge lamp of the present invention. The high-pressure discharge lamp of this embodiment includes a translucent airtight container 1, a pair of electrodes 2, 2, a pair of current introduction conductors 3, 3, a pair of sealing materials 4, 4, and an ionization medium, and constitutes an arc tube IT. To do.

  The translucent airtight container 1 is made of translucent ceramics, for example, translucent polycrystalline alumina ceramics. And it is provided with the surrounding part 1a and a pair of small diameter cylindrical parts 1b and 1b, and has comprised the integrally molded structure. The surrounding portion 1a has a bowl shape, and includes an intermediate cylindrical portion and a pair of hemispherical portions continuous to both ends thereof. The small-diameter cylindrical portion 1b has an elongated pipe shape, and the tip communicates with the top of the hemispherical portion of the surrounding portion 1a.

  The electrode 2 is composed of a rod-like body of doped tungsten, the tip faces the inside of the surrounding portion 1a of the translucent ceramic hermetic container 1, the base end is butt welded to the tip of the current introduction conductor 3, and the middle portion is a small diameter cylinder. The capillary 1b is inserted while forming a capillary that is a slight gap around the inside of the shaped portion 1b. A thin wire such as tungsten is wound around the electrode shaft portion of the electrode 2 located inside the small-diameter cylindrical portion 1b and the refractory portion of the current introduction conductor having the same diameter as the electrode shaft portion, and the electrode mount subcoil is mounted. Can be formed.

  The current introduction conductor 3 includes a sealing portion 3a and a halogen-resistant portion 3b connected in series. The sealing portion 3a is composed of a two-obed rod-like body, seals the translucent airtight container 1 in cooperation with a sealing material 4 to be described later, and has a base end outside the translucent airtight container 1. Is exposed. The halogen-resistant portion 3b is made of a molybdenum rod-like body, and its base end is butt welded to the distal end of the sealing portion 3a and inserted into the small-diameter cylindrical portion 1b of the translucent airtight container 1. Moreover, the base end of the electrode 2 is welded to the front-end | tip part.

  The sealing material 4 is made of a frit glass, that is, a melted and solidified body of a ceramic compound, and enters the small-diameter cylindrical portion 1b, and the sealing portion 3a and the small-diameter cylinder of the current introduction conductor 3 positioned in the small-diameter cylindrical portion 1b. In addition to being filled in the gap between the inner surface of the shape portion 1b, the base end of the halogen-resistant portion is also surrounded so that the surface of the sealing portion 3a is not exposed in the translucent airtight container 1.

  The ionization medium is composed of a metal halide and a rare gas.

  The metal halide includes at least a metal halide that mainly contributes to light emission. In the present embodiment, the metal halide mainly contributing to light emission contains at least one halide of thulium (Tm) and holmium (Ho). If desired, if thallium (Tl) is added in addition to the above, the blue light emission suppression phenomenon can be effectively reduced by regulating the inner volume of the translucent airtight container 1 to less than 0.8 mg / cc. can do. Further, in the present embodiment, the metal halide for forming the lamp voltage is mainly included, but mercury is essentially not included.

The rare gas is composed of a xenon-based rare gas of 1 to 5 atm when the ambient temperature is 25 ° C.
FIG. 2 is a front view showing a second embodiment for carrying out the high-pressure discharge lamp of the present invention. The high-pressure discharge lamp of this embodiment is a metal halide lamp with a rated lamp power of 100 W that can be adapted to general lighting applications, and includes an arc tube IT, an outer tube OT, a proximity conductor TW as a starting auxiliary means, and an ultraviolet enhancer UVE. Yes. In the figure, SG is a protective glass tube, SF is an arc tube support member, G is a getter, and B is a base.

  The arc tube IT is a high-pressure discharge lamp according to the first embodiment of the present invention shown in FIG.

  The outer tube OT is made of hard glass. Then, the arc tube IT, the proximity conductor TW and UV enhancer UVE as a starting auxiliary means, the protective glass tube SG, the arc tube support member SF, and the getter G are housed in predetermined positions, and the inside becomes a vacuum. ing. Further, the outer tube OT is provided with a flare stem 5 sealed at a neck portion located at the lower portion in the drawing. The flare stem 5 is provided with a pair of internal lead-in wires 6a and 6b protruding in an airtight manner into the outer tube OT.

  Further, the outer tube OT has the arc tube IT arranged at the substantially central portion of the outer tube OT along the central axis of the outer tube OT, and the upper current introduction conductor 3 is welded to a connection piece 10 to be described later and supported. At the same time, it is connected to the internal lead-in wire 6a via the arc tube support member SF. The current introduction conductor 3 below the arc tube IT is welded to and supported by the connection conductor 7 and is connected to the internal introduction line 6b via the connection conductor 7.

  One end of the proximity conductor TW is welded to the upper current introduction conductor 3 in FIG. 1 of the arc tube IT. The intermediate portion is wound around the translucent ceramic hermetic container 1 in the vicinity of the boundary between the upper small-diameter cylindrical portion 1b and the surrounding portion 1a to form the ring portion r1, and the tube is provided close to the outer periphery of the surrounding portion 1a. It extends downward along the axial direction. Further, the ring portion r2 is formed by being wound around the translucent airtight container 1 in the vicinity of the boundary portion between the lower diameter cylindrical portion 1b and the surrounding portion 1a.

  Therefore, in FIG. 2, the potential of an electrode (not shown) above the arc tube IT is applied to the adjacent conductor TW via the translucent airtight container 1 in the vicinity of the lower electrode. A large potential gradient is generated between the lower electrode. Therefore, when a high starting voltage of 5 kV or less is applied between the pair of electrodes 2 and 2, the start of the high pressure discharge lamp is promoted.

  In the ultraviolet enhancer UVE, the tip of one conductor 11 is sealed in a small and ultraviolet permeable airtight container to form an internal electrode. One conductor l1 is welded to the current introduction conductor 3 below the arc tube IT in FIG. The other conductor 12 holding the ultraviolet permeable airtight container is welded to a support frame 8 of the arc tube support member SF described later to form an external electrode. Therefore, the ultraviolet enhancer UVE is connected in parallel to the arc tube IT. A UV-radiating rare gas or the like is sealed in the UV-permeable airtight container.

  Thus, when a high starting voltage is applied between the pair of electrodes 2 and 2 of the ultraviolet enhancer UVE prior to the start of the high pressure discharge lamp, the discharge starts first, and the generated ultraviolet light is transferred below the arc tube IT. Irradiate near the electrode. As a result, electrons are emitted from the electrode 2 due to the photoelectric effect, which becomes initial electrons and the ionization medium in the arc tube IT is excited to be easily started.

  The protective glass tube SG is made of a quartz glass cylinder, and surrounds the arc tube IT in a separated state, thereby suppressing the scattering of fragments when the arc tube IT is ruptured. And it is supported by the arc tube support member SF as will be described later.

  The arc tube support member SF includes a support frame 8, a pair of support plates 9 and 9, and a connection piece 10. The support frame 8 is formed by bending a stainless steel rod into a vertically long U-shape and is connected to the internal lead-in wire 6a. The pair of support plates 9, 9 are formed of a stainless steel plate in a substantially disk shape and are fixed to the support frame 8. In addition, a through hole is formed in the center part of the pair of support plates 9, and by inserting the pair of small diameter cylindrical parts 1 b, 1 b of the translucent airtight container 1 through the through hole, the arc tube IT Is placed at the tube axis position of the outer tube OT, and the arc tube IT is supported in the tube axis direction. The connection piece 10 is welded to the upper part of the support frame 8, and is connected to the upper current introduction conductor 3 in the figure of the arc tube IT. The pair of support plates 9 and 9 are fitted to the upper and lower end surfaces of the protective glass tube SG, sandwich the protective glass tube SG therebetween, and are fixed to the arc tube support member SF. Therefore, the protective glass tube SG is supported by the arc tube support member SF via the pair of support plates 9 and 9.

  The getter G is a performance getter supported at the upper part in the figure of the arc tube support member SF.

  The base B is a screw-type base and is attached to the lower part of the outer tube OT in FIG. 1 and connected to the pair of internal lead-in wires 6a and 6b.

  Example 1 is a metal halide lamp shown in FIG.

Translucent airtight container: Polycrystalline alumina ceramics integrated molding, maximum inner diameter 6mm, wall thickness 0.5mm,
Total length 34mm, internal volume 0.12cc
Pair of electrodes: Distance between electrodes 4.2mm
Ionization medium: TmI ₃ -NaI = 4 mg (content ratio of TmI ₃ 75% by mass), ZnI ₂ = 0.1 mg,
Xe5 atmospheric pressure high voltage for starting: 4.5kV
Base, system: Base for general lighting HID, equipment for general lighting HID, dedicated ballast Electrical characteristics: Lamp voltage 45V, lamp power 30W, ballast uses dedicated ballast Luminous characteristics: Luminous efficiency 90 lm / W

Ionization medium: HoI ₃ -NaI = 4 mg (content ratio of HoI ₃ 75% by mass), ZnI ₂ = 0.1 mg,
Xe5 atmospheric pressure high voltage for starting: 4.5kV

Others are the same as Example 1.
Electrical characteristics: Lamp voltage 45V, lamp power 30W, ballast uses dedicated ballast Luminous characteristics: Luminous efficiency 88 lm / W

Ionization medium: TmI ₃ -NaI = 4 mg (content ratio of TmI ₃ 75% by mass), ZnI ₂ = 0.1 mg, Xe1.5 atm High voltage for starting: 3.4 kV

  Others are the same as Example 1.

Electrical characteristics: Lamp voltage 40V, lamp power 30W, ballast uses dedicated ballast Luminous characteristics: Luminous efficiency 86 lm / W

Ionization medium: TmI ₃ -NaI = 4 mg (content ratio of TmI ₃ 75% by mass), ZnI ₂ = 0.1 mg,
Xe1.5 bar Start high voltage: 3kV

  Others are the same as Example 1.

Electrical characteristics: Lamp voltage 38V, lamp power 30W, ballast uses dedicated ballast Luminous characteristics: Luminous efficiency 82 lm / W

Ionization medium: TmI ₃ -NaI = 4 mg (content ratio of TmI ₃ 75% by mass), ZnI ₂ = 0.1 mg,
Xe1 atmospheric pressure high voltage for starting: 2.8kV

  Others are the same as Example 1.

Electrical characteristics: Lamp voltage 37V, lamp power 30W, ballast uses dedicated ballast Luminous characteristics: Luminous efficiency 80 lm / W

[Comparative Example 1]
Ionization medium: TmI ₃ -NaI = 4 mg (content ratio of TmI ₃ 75% by mass), ZnI ₂ = 0.1 mg,
Xe16 atmospheric pressure high voltage for starting: 14kV
Base, System: Dedicated high withstand voltage base, Dedicated HID device, Dedicated ballast

  Others are the same as Example 1.

Electrical characteristics: Lamp voltage 70V, lamp power 30W
Luminous characteristics: Luminous efficiency 100 lm / W

[Comparative Example 2]
Ionization medium: HoI ₃ -NaI = 4 mg (content ratio of HoI ₃ 75% by mass), ZnI ₂ = 0.1 mg,
Xe16 atmospheric pressure high voltage for starting: 14kV

  Others are the same as Comparative Example 1.

Electrical characteristics: Lamp voltage 70V, lamp power 30W
Luminous properties: Luminous efficiency 97 lm / W

As is apparent from comparisons with Comparative Examples 1 and 2 in Examples 1 to 5, the lamp voltage and the light emission efficiency are sufficiently practical, and the starting high voltage starts at 3 to 5 kV.

FIG. 3 is a cross-sectional view of an essential part showing a third embodiment for implementing the high-pressure discharge lamp of the present invention. This embodiment is characterized in that the electrode 2 is provided with an optimized electrode mount subcoil 2b in comparison with the first embodiment.
In other words, in this embodiment, the electrode 2 is constituted by the electrode shaft portion 2a and the electrode mount subcoil 2b. The electrode shaft portion 2a is made of a rod-shaped body of doped tungsten. The electrode mount subcoil 2b is formed by winding a thin wire of doped tungsten around the electrode shaft portion 2a and the refractory portion 3b of the current introduction conductor 3 having the same diameter as the electrode shaft portion 2a. And the distance L between the terminal part of the surrounding part 1a side and the boundary part 1d of the small diameter cylinder part 1b and the surrounding part 1a is 0.05 mm or more. That is, the terminal end of the electrode mount subcoil 2b on the side of the surrounding portion 1a extends into the surrounding portion 1a by 0.05 mm or more. The tip end portion of the electrode shaft portion 2a is in an exposed state without the electrode mount subcoil 2b being wound.

  Example 6 is a metal halide lamp shown in FIG.

Translucent airtight container: Polycrystalline alumina ceramics integrated molding, maximum inner diameter 6mm, wall thickness 0.5mm,
Total length 34mm, internal volume 0.13cc
A pair of electrodes: Distance between electrodes 4.2mm, electrode mount subcoil is Mo mandrel shaft diameter
0.30 mm, coil wire diameter 0.18 mm, coil pitch 120%,
The end position on the enclosure side extends from the boundary 1d into the enclosure of 0.5 mm.

Capillary gap: Average 0.02mm
Ionization medium: DyI ₃ -HoI ₃ -TmI ₃ -NaI-LiI-TlI = 4 mg (TmI ₃ + HoI ₃ : 0.4 mg = 10% by mass)
There was a tendency that ZnI ₂ = 1.2 mg, Xe 2.4 atm, and metal halide retention was distributed more on the terminal side of the electrode mount subcoil.

High voltage for starting: 3.9kV
Electrical characteristics: Lamp voltage 35V, lamp power 30W
Luminous properties: Luminous efficiency 80 lm / W, duv. + 0.0000
Erosion of small diameter cylinder part: The wall thickness of the maximum erosion part was 99.5% of the initial value at the time of lighting 500h.

Others are the same as Example 1.

Ionization medium: TmI ₃ -NaI = 4 mg (TmI ₃ 3 mg, content ratio 75% by mass), ZnI ₂ = 0.2 mg,
Xe 2.4 atm, metal halide of electrode mount subcoil
There was a tendency to accumulate a lot on the terminal side.

High voltage for starting: 3.9kV
Electrical characteristics: Lamp voltage 37V, lamp power 30W
Luminous properties: Luminous efficiency 88 lm / W, duv +0.0100
Erosion of small diameter cylinder part: The wall thickness of the maximum erosion part was 99.5% of the initial value at the time of lighting 500h.

Others are the same as Example 6.

Ionization medium: TmI ₃ -NaI-LiI = 4 mg (TmI ₃ : 1.4 mg = 35% by mass)
ZnI ₂ = 0.2mg, Xe2.4atm, metal halide retention
There was a tendency to distribute more to the terminal side of the subcoil.

High voltage for starting: 3.9kV
Electrical characteristics: Lamp voltage 36V, lamp power 30W
Luminous properties: Luminous efficiency 80 lm / W, duv +0.0050
Erosion of small diameter cylinder part: The wall thickness of the maximum erosion part was 99.5% of the initial value at the time of lighting 500h.

Others are the same as Example 6.

A pair of electrodes: The distance between the electrodes is 4.2mm, and the terminal position of the electrode mount subcoil on the enclosing portion side is
It extends into the 0.1 mm enclosure from the boundary 1d.
Capillary gap: average 0.1mm

Ionization medium: TmI ₃ -NaI-LiI = 4 mg (TmI ₃ : 3 mg = 75% by mass)
ZnI ₂ = 0.2 mg, Xe 2.4 atmospheres, and metal halide retention tended to be slightly distributed toward the proximal end of the electrode mount subcoil.

High voltage for starting: 3.9kV
Electrical characteristics: Lamp voltage 35V, lamp power 30W
Luminous properties: Luminous efficiency 86 lm / W, duv +0.0050
Erosion of small diameter cylinder part: The wall thickness of the maximum erosion part was 95% of the initial value at the time of lighting 500h.

Others are the same as Example 6.

[Comparative Example 3]
A pair of electrodes: 4.2mm distance between electrodes
It is retracted 1 mm from the boundary portion 1d toward the sealing portion.

Ionization medium: TmI ₃ -NaI = 4 mg (content ratio of TmI ₃ 75% by mass), ZnI ₂ = 0.2 mg,
Xe 2.4 atm, metal halide on the base end side of the electrode mount subcoil
There was a tendency to stay a lot.

High voltage for starting: 3.9kV
Electrical characteristics: Lamp voltage 25V, lamp power 30W
Luminous properties: Luminous efficiency 70lm / W, duv 0.0100
Erosion of small diameter cylinder part: The wall thickness of the maximum erosion part was 65% of the initial value at the time of lighting 500h.

Others are the same as Example 6.

[Comparative Example 4]
A pair of electrodes: The distance between the electrodes is 4.2 mm, and the terminal position of the electrode sub-coil surrounding portion is the boundary portion 1d.
Extends 0.5mm into the enclosure.

Capillary gap: Average 0.02mm
Ionization medium: TmI ₃ -NaI = 4 mg (content ratio of TmI ₃ 75% by mass), Hg = 0.5 mg, Ar 0.2 atm,
Metal halide tends to stay in the base end of electrode subcoil
Met.

High voltage for starting: 2.7kV
Electrical characteristics: Lamp voltage 90V, lamp power 30W
Luminous properties: Luminous efficiency 90 lm / W, duv 0.0000
Erosion of small diameter cylinder part: The wall thickness of the maximum erosion part was 100% of the initial value at the time of lighting 500 hours.

Others are the same as Example 6.

FIG. 4 is a graph illustrating an allowable range of each component in the embodiment of the present invention described above. In the figure, the “Xe enclosure pressure” on the horizontal axis represents the enclosure pressure (atmosphere) in terms of room temperature (25 ° C.) when xenon is enclosed as a rare gas mainly composed of xenon, and the vertical axis represents “efficiency lm / W, lamp "Voltage V" indicates luminous efficiency (lm / W) and lamp voltage (V), and breakdown start voltage (kV) on the right indicates breakdown voltage / start voltage (kV). In addition, the curve in the figure shows the following characteristics from top to bottom at a vertical position at a rare gas filling pressure of 5 atm.
(1) “TmHo 75% efficiency” is the luminous efficiency when the encapsulation ratio of Tm (Ho) halide to the total amount of luminescent metal halide is 75%. (2) “TmHo 45% efficiency” is also the luminous efficiency at 45% (3) “TmHo 75% voltage” is the starting voltage (4) “TmHo 45% voltage” is 45%, and the starting voltage (5) “common breakdown voltage” is 45%. %, 75% common)

  As can be seen from FIG. 4, the luminous efficiency when the encapsulation ratio of Tm (Ho) halide to the total amount of luminescent metal halide is 75% is 76 lm / W when the rare gas encapsulation pressure is 0.7 atm, and the lamp voltage is 35V. Similarly, at 5 atm, the luminous efficiency is 90 lm / W, the lamp voltage is 45 V, and the dielectric breakdown voltage / starting voltage is 4.5 kV. Further, at 10 atmospheres, the pressure is about 98 lm / W, the lamp voltage is about 55 V, and the dielectric breakdown voltage / starting voltage is 5.3 kV. Furthermore, the noble gas filling pressure is 80 lm / W, the lamp voltage is 37 V, and the dielectric breakdown voltage / starting voltage is 3.2 kV at 1 atm.

  Thus, the practical lower limit luminous efficiency is set to 70 lm / W, the practical lower limit lamp voltage is set to 35 V, and the practical upper limit dielectric breakdown voltage / starting voltage is set to 6.3 kV. It can be seen that when the xenon-based rare gas filling pressure is 1 to 5 atm, the luminous efficiency and the lamp voltage are not lower than the practical lower limit and the dielectric breakdown voltage / starting voltage is not higher than the practical upper limit. If the breakdown voltage / starting voltage is allowed to slightly exceed the practical upper limit, the xenon-based rare gas filling pressure is more than 5 atmospheres and 10 atmospheres or less, and sufficiently high luminous efficiency and lamp voltage are obtained. You can see that

    FIG. 5 is a cross-sectional view showing a ceiling-embedded downlight as an embodiment for carrying out the lighting device of the present invention.

  In the figure, 11 is a high-pressure discharge lamp, and 12 is a lighting fixture body.

  The high-pressure discharge lamp 11 is the same as that in the second embodiment for implementing the high-pressure discharge lamp of the present invention shown in FIG.

  The luminaire main body 12 constitutes a ceiling-embedded downlight, and includes a base 12a and a reflector 12b. Since the base 12a is embedded in the ceiling, the base 12a has a ceiling contact edge 12a1 at the lower end. The reflection plate 12b is supported by the base body 12a and surrounds the light emission center of the high-pressure discharge lamp 11 so that it is located at substantially the focal point.

  A high-pressure discharge lamp lighting device (not shown) for lighting the high-pressure discharge lamp 11 is disposed on the lighting fixture body 12 or at a position adjacent to the lighting fixture body 12 or a remote position. It can be set separately.

Sectional drawing which shows the 1st form for implementing the high pressure discharge lamp of this invention The front view which shows the 2nd form for implementing the high pressure discharge lamp of this invention Sectional drawing of the principal part which shows the 3rd form for implementing the high pressure discharge lamp of this invention The graph explaining the allowable range of each component in the embodiment of the present invention Sectional drawing which shows the ceiling embedded downlight as one form for implementing the illuminating device of this invention

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Translucent airtight container, 1a ... Enclosing part, 1b ... Small diameter cylinder part, 1c ... Discharge space, 2 ... Electrode, 2a ... Electrode axial part, 2b ... Electrode mounting subcoil, 3 ... Current introduction conductor, 3a ... Sealing Attachment part, 3b ... Halogen resistant part, 4 ... Seal material, 5 ... Stem, B ... Base, IT ... Aluminum tube, OT ... Outer tube, SF ... Support frame, SG ... Protective glass, TW ... Proximity conductor, UVE ... UV enhancer

Claims (6)

A translucent airtight container with a discharge space inside;
A pair of electrodes disposed in the translucent airtight container so as to be present in the discharge space;
It contains at least one halide of thulium (Tm) and holmium (Ho) as a metal halide in which the metal halide mainly contributes to light emission, including a rare gas and a metal halide. An ionization medium which is mainly composed of atmospheric xenon and does not contain mercury and is enclosed in a translucent airtight container;
A high-pressure discharge lamp comprising:   2. The high-pressure discharge lamp according to claim 1, wherein at least one halide of thulium (Tm) and holmium (Ho) is 10% by mass or more based on the total amount of metal halides mainly contributing to light emission. .   The ionization medium contains, in addition to a metal halide mainly contributing to light emission, a metal halide mainly having a ionization energy of 8 eV or more and a melting point of 500 ° C. or less as a metal halide for forming a lamp voltage. The high-pressure discharge lamp according to claim 1 or 2. The translucent airtight container includes a surrounding portion in which a discharge space is formed, a pair of small diameter cylindrical portions that communicate with the inside of the surrounding portion and extend from both ends of the surrounding portion in the tube axis direction, and a small diameter cylindrical portion A translucent ceramic hermetic container in which the distal end portion of the current introduction conductor is inserted inside, the base end portion is exposed to the outside, and the end portion of the small diameter cylindrical portion is sealed together with the current introduction conductor;
The pair of electrodes includes an electrode shaft portion and an electrode mount subcoil, and is inserted into the small-diameter cylindrical portion of the translucent ceramic hermetic container with a slight gap between the inner surface. The tip of the current introduction conductor is supported and the tip is exposed in the surrounding portion, and the electrode mount subcoil is wound around the electrode shaft from the middle to the base end of the electrode shaft, and the electrode mount subcoil An end portion of the surrounding portion is disposed to extend from the boundary portion between the small-diameter cylindrical portion and the surrounding portion into the surrounding portion by 0.05 mm or more;
The high-pressure discharge lamp according to any one of 1 to 3, wherein An outer tube containing an arc tube inside and having a base at one end;
Start assisting means disposed inside the outer tube to assist in starting so that a discharge starts in the arc tube when a high starting voltage of 3 to 5 kV is applied between the pair of electrodes;
The high pressure discharge lamp according to any one of claims 1 to 4, further comprising: A lighting device body;
A high-pressure discharge lamp according to any one of claims 1 to 5 disposed in a lighting device body;
An illumination device comprising:

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