JP2007088348A - Illumination device, backlight device, and liquid crystal display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize a lighting device having high luminous efficiency.
An illumination device of the present invention includes an LED element 1 that emits light, a phosphor 5 that is excited by light emitted from the LED element 1 and emits light, and the LED element 1 and the phosphor 5. A package 3 having a recess for the purpose, and a transparent plate 4 for closing the surface of the package 3 where the opening of the recess is provided. The transparent plate 4 includes an ultraviolet cut filter 6 for reflecting light emitted from the LED element 1. Thereby, it can suppress that the light radiate | emitted from LED element 1 is discharge | released outside, the frequency which the fluorescent substance 5 light-emits becomes high, and can implement | achieve the illuminating device with higher luminous efficiency.
[Selection] Figure 1

Description

  The present invention relates to an illumination device used for a backlight light source or an illumination light source for a liquid crystal display, a backlight device equipped with a plurality of the illumination devices, and a liquid crystal display device equipped with the backlight device.

  Conventionally, illumination devices using light emitting elements such as light emitting diodes (LEDs) have been widely used for illumination light sources, backlight light sources for liquid crystal displays, and the like (see, for example, Patent Documents 1 to 3).

  In order to realize white light emission in the LED, it is necessary to emit light of three colors corresponding to the three colors of R, G, and B. As a method of emitting light of three colors of R, G, and B, it is possible to simultaneously emit three LED elements corresponding to the three colors.

  As another method, there is a method in which a fluorescent material is excited by an LED to emit light (see, for example, Patent Document 4). For example, a configuration in which a fluorescent material is excited by an LED to emit light is a combination of a blue light emitting LED as an LED and a material that is excited by a blue light emitting LED as a fluorescent material and emits light in a visible region other than blue. Can be mentioned. Examples of the fluorescent substance include a combination of a substance emitting red light and a substance emitting yellow light or a substance emitting green light.

  Recently, a configuration in which an LED that emits light in the ultraviolet region and a fluorescent material that is excited by the light in the ultraviolet region and emits light in the visible region has been studied.

The luminosity of the illuminating device having the above configuration is increasing year by year, and the illuminating device having the above-described configuration is being developed as a backlight source for large liquid crystals or a large illuminating light source.
JP-A-8-330635 (Released on December 13, 1996) JP 2002-223006 (Released on August 9, 2002) JP 5-175614 (released July 13, 1993) JP 2002-252372 (released September 6, 2002)

  However, the conventional configuration has a problem that the light emission efficiency is low.

  Specifically, in the lighting apparatus configured to excite the fluorescent material by the LED and emit light, light that does not act on the fluorescent material out of the light emitted from the LED is emitted to the outside, so that the light emission efficiency is lowered. End up. For example, in the case of a blue light emitting LED, ultraviolet light is included in a part of the emitted light, and the ultraviolet light does not contribute to the visible light emitted from the lighting device, so that it does not act on the fluorescent material. Therefore, the light emission efficiency is lowered by the amount of light in the ultraviolet region emitted. In particular, in the case of an LED that emits light in the ultraviolet region, almost all light does not contribute to light in the visible region, so the light emission efficiency is very low.

  The present invention has been made in view of the above-described problems, and an object thereof is to realize an illumination device with higher luminous efficiency.

  In order to solve the above problems, a lighting device according to the present invention emits light in the visible region by emitting light that emits light including at least a component other than the visible region and light emitted from the light emitting device. In an illuminating device including a fluorescent material to be opened and an opening for emitting internal light to the outside, and including a package for arranging the light emitting element and the fluorescent material inside, the light emitting element emits the light. A wavelength cut filter that reflects light outside the visible region of light is provided in the opening of the package.

  According to said structure, since the wavelength cut filter is provided in the opening part of the said package, the light of those other than the visible region radiate | emitted from a light emitting element is not emitted outside the package, but the said wavelength cut filter It is reflected by the filter and stays inside the package. That is, light outside the visible region emitted from the light emitting element stays in the package until the light emitting material is excited. Therefore, a higher proportion of the light emitted from the light emitting element can contribute to the light in the visible region emitted from the lighting device, so that the luminous intensity of the light emitted from the lighting device is increased. Therefore, since the electric power required to generate light with a constant illuminance is small, there is an effect that it is possible to provide an illumination device with higher luminous efficiency and less power consumption.

  In the illumination device according to the present invention, it is preferable that the package is provided with a recess for arranging the light emitting element and the fluorescent material therein.

  Thereby, a package can be formed by performing simple processing which only provides a recessed part in a member. For this reason, there exists the further effect that manufacturing cost can be suppressed.

  Moreover, in the illuminating device according to the present invention, it is preferable that a transparent member for closing the opening of the package is further installed on the surface of the package where the opening is formed.

  Thereby, the inside of a package can be protected by a transparent member. Therefore, the further effect that durability of an illuminating device can be made higher is produced.

  Moreover, in the illuminating device which concerns on this invention, it is preferable that the said transparent member is flat plate shape.

  Thereby, a transparent member can be manufactured easily. For this reason, there exists the further effect that manufacturing cost can be suppressed.

  Moreover, in the illuminating device which concerns on this invention, it is preferable that the said wavelength cut filter is installed in the surface facing the inner side of the said package in the said transparent member.

  Thereby, another filter etc. can be provided in the outer surface of a transparent member. Therefore, there is an additional effect that the characteristics of the emitted light can be further changed.

  In the illumination device according to the present invention, it is preferable that the transparent member is integrated with the wavelength cut filter.

  Thereby, the number of parts which comprise an illuminating device can be reduced. Therefore, the assembly man-hour in a manufacturing process can be reduced. Therefore, there is an additional effect that the manufacturing cost can be suppressed.

  Further, in the lighting device according to the present invention, an electrical wiring for electrically connecting the light emitting element to external power is provided on the surface of the transparent member, and the light emitting element is provided on the transparent member. It is preferable to be installed on the surface facing the inner side.

  Thereby, since a light emitting element is installed on a transparent member, the wiring for electrically connecting a light emitting element with external electric power can be provided on a transparent member. The transparent member has a flat plate shape, and wiring can be more easily provided by a printed circuit board technique or the like as compared with a package having a complicated structure inside. Therefore, there is a further effect that the lighting device can be manufactured more easily.

  In the lighting device according to the present invention, the width of the electrical wiring in the direction perpendicular to the surface on which the opening of the package is provided is horizontal with respect to the surface on which the opening of the package is provided. It is preferable that the width is wider.

  As a result, the cross-sectional area of the wiring material is increased, so that the thermal conductivity in the wiring is increased. Therefore, the wiring material has higher thermal conductivity than the transparent member, so that the temperature rise of the transparent member can be suppressed. it can. In connection with this, the temperature rise of the light emitting element provided on the transparent member is also suppressed. In general, when the temperature of the light emitting element rises, the light output and life characteristics of the light emitting element deteriorate. Therefore, there is an additional effect that it is possible to provide a lighting device with higher luminous efficiency and longer light emission lifetime.

  The lighting device according to the present invention is a lighting device mounted on a liquid crystal display device including a plurality of color filters, and cuts light in a band where the spectral distributions of the transmission characteristics of the color filters of the respective colors overlap each other. Therefore, it is preferable that a second wavelength cut filter is provided in the opening of the package.

  According to said structure, the 2nd wavelength cut filter for cutting the light of the zone | band with which the spectrum distribution of the transmission characteristic of each color filter with which a liquid crystal display device is provided overlaps is provided in the opening part of the package. Thereby, the light irradiated from the said opening part can be made into the wavelength suitable for a liquid crystal display device to display an image. Thereby, the said illuminating device can be used suitably as a backlight of a liquid crystal display device.

  Note that any of the plurality of color filters may be used, and examples thereof include three color filters having R, G, and B characteristics.

  In the lighting device according to the present invention, it is preferable that the package is filled with a transparent resin containing the fluorescent material.

  This eliminates the need to apply the fluorescent material to the inner surface of the package, facilitating the application of the fluorescent material in the manufacturing process of the lighting device. Therefore, there is a further effect that the lighting device can be manufactured more easily.

  Moreover, in the illuminating device which concerns on this invention, it is preferable that the light radiate | emitted from the said light emitting element is light of an ultraviolet region.

  Since the light emitted from the light emitting element is light in the ultraviolet region, the light in the visible region is only light emitted from the fluorescent material. Therefore, by selecting an arbitrary fluorescent material, there is an additional effect that the wavelength range of the emitted light can be easily adjusted.

  In the lighting device according to the present invention, it is preferable that the package is made of ceramic.

  Thereby, the heat dissipation of a package can be improved and the temperature rise inside a package can be suppressed. Accordingly, the temperature rise of the light emitting element provided inside the package is also suppressed. In general, when the temperature of the light emitting element rises, the light output and life characteristics of the light emitting element deteriorate. Therefore, there is an additional effect that it is possible to provide a lighting device with higher luminous efficiency and longer light emission lifetime.

  In the illumination device according to the present invention, it is preferable that a plurality of the light emitting elements are provided inside the package.

  Thereby, the intensity | strength of light can be raised more. Therefore, there is an additional effect that light emission characteristics with higher luminous intensity can be obtained.

  In the illumination device according to the present invention, it is preferable that a second transparent member is further provided on the second wavelength cut filter.

Thereby, the 2nd wavelength cut filter provided on the transparent member can be protected from the outside. Further, another filter or the like can be provided on the outer surface of the transparent member.
Therefore, the durability of the second wavelength cut filter can be further increased, and the effect of further changing the characteristics of the emitted light can be achieved.

  In order to solve the above-described problems, a backlight device according to the present invention is characterized in that a plurality of the lighting devices are arranged on a transparent member in the backlight device including the lighting device.

  According to said structure, since the said illuminating device is mounted, there exists an effect that a luminous device with higher luminous efficiency and less power consumption can be provided. In addition, since a plurality of the lighting devices are arranged on the transparent member, it is not necessary to separately use a wiring board or the like by arranging electric wiring on the transparent member. Thereby, since the number of component parts can be reduced, there exists an effect that a backlight apparatus can be manufactured at lower cost.

  In order to solve the above problems, the liquid crystal display device according to the present invention is equipped with the backlight device.

  According to said structure, since the said backlight apparatus is mounted, there exists an effect that a liquid crystal display device with higher luminous efficiency and less power consumption can be provided.

  As described above, the illumination device according to the present invention includes the wavelength cut filter for reflecting the light emitted from the light emitting element on the transparent member. Therefore, there is an effect that it is possible to provide a lighting device with higher luminous efficiency.

(Embodiment 1)
An embodiment of the present invention will be described below with reference to FIGS.

  The ultraviolet region refers to a wavelength range of about 1 nm to 400 nm whose wavelength is longer than X-rays and shorter than visible light. The visible region is a wavelength range of about 400 nm to 800 nm, which has a wavelength longer than ultraviolet rays and shorter than infrared rays.

  FIG. 1 is a cross-sectional view of the lighting apparatus according to the present embodiment. FIG. 2 is a perspective view showing a schematic configuration of the illumination device according to the present embodiment.

  As shown in FIG. 1, the illumination device 101 includes an LED element (light emitting element) 1, a package 3, a transparent plate (transparent member) 4, an ultraviolet cut filter (wavelength cut filter) 6, and a phosphor (fluorescent substance) 5. It is out.

  The package 3 serves as a base in an illumination device for storing the LED element 1 and the phosphor 5 therein. Specifically, the package 3 has a shape in which a recess is provided on the upper surface of a substantially quadrangular prism having a square bottom surface. The concave portion provided in the package 3 has a shape in which the tip of the cone is cut in parallel with the bottom surface of the cone, and is provided so that the bottom surface of the cone overlaps the upper surface of the package 3. Thereby, a circular opening 18 is formed on the upper surface of the package 3. The recess is provided such that the opening 18 is wider than the bottom surface of the recess, and the bottom surface of the recess is parallel to the bottom surface and the top surface of the package 3.

  The LED element 1 is fixed by being adhered to the bottom surface of the recess in the package 3 by Ag paste or eutectic. The LED element 1 is electrically connected to external power by an Au wire 2 and emits light in the ultraviolet region by the external power. The light in the ultraviolet region emitted from the LED element 1 has a peak wavelength range of 360 nm to 415 nm.

  The phosphor 5 is excited by the light in the ultraviolet region generated by the LED element 1 emitting light, and emits light in the visible region. The phosphor 5 is applied to the side surface of the recess in the package 3. The phosphor 5 is obtained by dispersing three types of fluorescent substances that emit light of R, G, and B excited by light in the ultraviolet region in a material such as a resin, and the light emitted from the LED element 1. R, G, B light of each color is emitted.

  The transparent plate 4 is for protecting the LED element 1, the phosphor 5 and the like installed inside the package 3, and has a flat plate shape whose bottom surface is substantially equal to the top surface of the package 3. The bottom surface of the transparent plate 4 is provided in contact with the top surface of the package 3, and the surface of the package 3 where the opening is provided is closed.

  The ultraviolet cut filter 6 reflects light in the ultraviolet region emitted from the LED element 1. The ultraviolet cut filter 6 is provided on the surface of the transparent plate 4 on the package 3 side. The ultraviolet cut filter 6 has a flat plate shape whose bottom surface is substantially the same as the opening 18 of the package 3 so as not to emit ultraviolet light emitted from the LED element 1 to the outside. The ultraviolet cut filter 6 cuts light having a peak wavelength of 425 nm or less and transmits light in the visible region.

  Below, operation | movement of the illuminating device 101 is demonstrated.

  A part of the light emitted from the LED element 1 excites the phosphor 5 and becomes R, G, B light. The light of R, G and B colors emitted from the phosphor 5 is transmitted through the ultraviolet cut filter 6 and the transparent plate 4 and emitted to the outside. On the other hand, light that reaches the ultraviolet cut filter 6 directly or by reflection without acting on the phosphor 5 is reflected by the ultraviolet cut filter 6 and remains inside the package 3. As described above, the ultraviolet cut filter 6 reflects only the light in the ultraviolet region emitted from the LED element 1 and transmits the light of R, G, and B colors emitted from the phosphor 5 that is the light in the visible region. As a result, the light reflected from the ultraviolet cut filter 6 remains inside the package 3 until it is absorbed by the phosphor 5. Therefore, most of the light emitted from the LED element 1 is finally converted into R, G, B light. Therefore, the light emitted from the LED element 1 can be used effectively, and the light emission efficiency of the lighting device can be improved.

  The light emitting element may have any configuration as long as it emits light by external power, and is not limited to the LED element 1. For example, if the light emitting element is a laser, substantially the same effect as in the present embodiment can be obtained. Further, the wavelength range of the light emitted from the light emitting element is not limited to the ultraviolet region as long as it is outside the wavelength range of the light transmitted through the wavelength cut filter 6. In general, the fluorescent substance shifts the wavelength of the emitted light to the longer wavelength side relative to the wavelength of the exciting light. For this reason, the wavelength range of the light emitted from the light emitting element is more preferably in the ultraviolet region.

  In the present embodiment, the wavelength range of the light emitted from the LED element 1 does not include light in the visible region, but may include light in the visible region. For example, when a blue light emitting LED is used as the LED element 1, the light emitted from the blue light emitting LED includes blue visible region light and ultraviolet region light. For this reason, if the phosphor 5 is configured to emit red and green light when excited by light in the ultraviolet region, the blue light emitted from the blue light emitting LED itself and the red and green emitted from the phosphor 5 are used. By combining with this light, white light can be emitted by the lighting device.

  Moreover, in this Embodiment, although the package 3 has the shape which provided the recessed part, if the LED element 1 and the fluorescent substance 5 can be accommodated in an inside, it will not be limited to this structure. However, if it is a structure like the package 3, a package can be formed by giving the simple process which only provides the recessed part to a member. For this reason, since manufacturing cost can be suppressed, it is more preferable.

  Examples of the material constituting the package 3 include materials having excellent heat dissipation, such as ceramic materials and metals (copper and aluminum). Since the ceramic material is excellent in heat dissipation, it is more preferable in that the temperature rise of the lighting device 101 can be suppressed. Generally, when the temperature of the LED element 1 increases, the light output of the LED element 1 tends to decrease or the light emission lifetime tends to be shortened. Therefore, by suppressing the temperature rise of the lighting device 101, a lighting device with higher light emission efficiency and a longer light emission lifetime can be realized.

In the present embodiment, since the durability of the lighting device can be further increased,
More preferably, a transparent plate 4 is provided. However, the transparent plate 4 may not be provided.

  Moreover, since the transparent plate 4 can manufacture a transparent member easily and can suppress manufacturing cost, it is more preferable that it is plate shape. However, the present invention is not limited to this, and may be a non-planar shape such as a hemispherical shape.

  Examples of the material constituting the transparent plate 4 include materials that are optically transparent to light in the visible region. Here, optically transparent with respect to light in the visible region means that the transmittance in the visible region is 70% or more. If the transparent member 4 is optically transparent with respect to light in the visible region, light absorption by the member can be suppressed, and light use efficiency can be increased.

  Specific examples of the material constituting the transparent plate 4 include inorganic substances such as glass and organic compounds such as PET, and glass is more preferable.

  Examples of the fluorescent material used for the phosphor 5 include the following.

Specifically, as a fluorescent substance that emits red light, M ₂ O ₂ S: Eu (where M is one or more elements selected from La, Gd, and Y), 0.5 MgF _2. 3.5MgO.GeO ₂ : Mn, Y ₂ O ₃ : Eu, Y (P, V) O ₄ : Eu, YVO ₄ : Eu, and the like. The fluorescent substances that emit red light may be used alone or in combination of two or more.

Examples of fluorescent substances that emit blue light include A ₁₀ (PO ₄ ) ₆ Cl ₂ : Eu (where A is one or more elements selected from Sr, Ca, Ba, Mg, Ce), XMg ₂ Al ₁₆ O ₂₇ : Eu (where X is one or both elements selected from Sr and Ba), XMgAl ₁₀ O ₁₇ : Eu (where X is one or both selected from Sr and Ba) Element), ZnS: Ag, Sr ₁₀ (PO ₄ ) ₆ Cl ₂ : Eu, Ca ₁₀ (PO ₄ ) ₆ F ₂ : Sb, Z ₃ MgSi ₂ O ₈ : Eu (where Z is Sr, Ba, Ca And any one or more elements selected from SrMgSi ₂ O ₈ : Eu, Sr ₂ P ₂ O ₇ : Eu, CaAl ₂ O ₄ : Eu, Nd, and the like. The fluorescent substances emitting blue light may be used alone or in combination of two or more.

Fluorescent materials that emit green light include RMg ₂ Al ₁₆ O ₂₇ : Eu, Mn (where R is one or both elements selected from Sr and Ba), RMgAl ₁₀ O ₁₇ : Eu, Mn (provided that , R is any one or both elements selected from Sr and Ba), ZnS: Cu, SrAl ₂ O ₄ : Eu, SrAl ₂ O ₄ : Eu, Dy, ZnO: Zn, Zn ₂ Ge ₂ O ₄ : Mn, Zn ₂ SiO ₄ : Mn, Q ₃ MgSi ₂ O ₈ : Eu, Mn (where Q is one or more elements selected from Sr, Ba, Ca). The fluorescent substances emitting green light may be used alone or in combination of two or more.

  Moreover, in this Embodiment, although the ultraviolet cut filter 6 is installed in the surface facing the inner side of the package 3 in the transparent plate 4, it is not limited to this. For example, it may be installed on the surface facing the outside of the transparent plate 4. However, since the ultraviolet cut filter 6 is installed on the surface of the transparent plate 4 facing the inside of the package 3, another filter or the like can be provided on the outer surface of the transparent plate 4. Therefore, it is more preferable because the illumination device can be configured to further change the characteristics of the emitted light.

  In the lighting device 101, the transparent plate 4 and the ultraviolet cut filter 6 are separate members, but the transparent plate 4 and the ultraviolet cut filter 6 may be integrated. If the transparent plate 4 and the ultraviolet cut filter 6 are integrated, the number of parts constituting the lighting device can be reduced, and therefore the number of assembly steps in the manufacturing process can be reduced. Therefore, the manufacturing cost can be suppressed, which is more preferable.

  As described above, the illumination device according to the present invention includes a wavelength cut filter that reflects light outside the visible region in the light emitted from the light emitting element. The emitted light outside the visible region is less likely to be emitted outside the package. Thereby, light outside the visible region emitted from the light emitting element stays in the package until the light emitting material is excited. Therefore, the light emitted from more light emitting elements can contribute to the light in the visible region emitted from the illumination device, so that the luminous intensity of the light emitted from the illumination device is increased. Therefore, since light in the visible region can be emitted from the lighting device with less power, a lighting device with higher luminous efficiency and less power consumption can be realized.

(Embodiment 2)
The second embodiment of the present invention will be described in detail below with reference to FIGS. However, the same members as those in the first embodiment described above are denoted by the same reference numerals, and the description thereof is omitted.

  FIG. 3 is a cross-sectional view of the lighting apparatus according to the present embodiment. FIG. 4 is an enlarged view of FIG. 3 showing the surface configuration of the transparent plate of the lighting apparatus according to the present embodiment.

  As shown in FIG. 3, the illumination device 201 is different from the first embodiment in that the LED element 1 is installed on the surface of the transparent plate 4 on the package 3 side.

  As shown in FIG. 4, the transparent plate 4 on which the LED element 1 is installed is provided with wiring (electrical wiring) 15 on the surface on the concave side of the package 3 to electrically connect the LED element 1. ing.

  Unlike Embodiment 1, the phosphor 5 is applied to the entire recess since the LED element 1 is not provided on the bottom surface of the recess of the package 3.

  In the lighting device 201, wiring 15 for electrically connecting the LED elements 1 is provided on the surface of the transparent plate 4, and the LED elements 1 are installed on the surface of the transparent plate 4 facing the inside of the package 3. Has been. Thereby, since the LED element 1 is installed on the transparent plate 4, the wiring 15 for electrically connecting the LED element 1 can be provided on the transparent plate 4. The transparent plate 4 has a flat plate shape, and wiring can be provided more easily by a printed circuit board technique or the like as compared with the package 3 having a complicated structure inside. Therefore, the lighting device can be manufactured more easily.

  Also, in the lighting device 201, as shown in FIG. 4, the wiring 15 in the transparent plate 4 has a width W in the direction perpendicular to the surface of the package 3 where the opening is provided, and the opening of the package 3 is provided. It is wider than the horizontal width with respect to the surface. Thereby, since the cross-sectional area of the wiring 15 is increased, the thermal conductivity in the wiring 15 is increased. Since the material of the wiring 15 such as copper is higher in thermal conductivity than the transparent plate 4, the temperature rise of the transparent plate 4 can be suppressed. In connection with this, the temperature rise of the LED element 1 provided on the transparent plate 4 is also suppressed. In general, when the temperature of the light emitting element rises, the light output and life characteristics of the light emitting element deteriorate. Accordingly, it is possible to provide a lighting device with higher emission efficiency and a longer emission lifetime.

  In order to increase the thermal conductivity of the wiring 15, not only the width W in the vertical direction of the wiring 15 but also the width in the horizontal direction with respect to the surface on which the opening of the package 3 is provided can be increased. is there. However, in the normal wiring, the width W in the vertical direction is smaller than the width in the horizontal direction. Compared with the vertical direction, there is less space in the horizontal direction on the wiring board, and the area is limited. Therefore, it is difficult to spread the wiring in the horizontal direction.

  Since the operation of the lighting device 201 is substantially the same as that of the lighting device 101, description thereof is omitted.

(Embodiment 3)
A third embodiment of the present invention will be described in detail below with reference to FIG. However, the same members as those in the first and second embodiments described above are denoted by the same reference numerals, and the description thereof is omitted.

  In the first embodiment, an illumination device is formed with the same configuration as that of the first embodiment except that a wavelength cut filter (second wavelength cut filter) 8 is further provided on the transparent plate 4. Yes.

  FIG. 5 is a cross-sectional view of the lighting apparatus according to the present embodiment.

  As shown in FIG. 5, in the illumination device 301, the wavelength cut filter 8 is installed on the transparent plate 4. The wavelength cut filter 8 has a flat plate shape having a size substantially equal to that of the opening 18 so as to be able to act on all light emitted to the outside through the transparent plate 4.

  The illumination device 301 is a backlight illumination device used in a liquid crystal display device. In a liquid crystal display device, color display is generally performed by coloring light from a backlight into R, G, and B colors using a color filter. A liquid crystal display device using an LED as a backlight device has a drawback that the color reproduction range is narrow and the color rendering property is lacking because the emission spectrum distribution is different from the spectral distribution of the transmission characteristics of the color filter. More specifically, the liquid crystal display device uses three types of color filters of R, G, and B, and a full color display is performed by combining these three colors. For this reason, if the peak width in each of the spectrum distributions of R, G, and B is broad, the color purity of each becomes low, the color reproduction range is narrow, and the color rendering is low. For example, when a light source combining a blue LED, which is a white LED with the highest luminous intensity at present, and a yellow light emitting phosphor is used as a backlight, two types of light, blue light emitted from the LED and yellow light emitted from the phosphor, are used. Therefore, there is little light having a wavelength corresponding to the green peak and the red peak, and an intermediate color display is obtained when displaying green and red.

  In addition, there is a light source that combines a blue LED, a green phosphor, and a red phosphor in order to obtain the same three peak distributions as the transmission characteristics of the color filter. However, in these configurations, although the spectrum distribution has three peaks of R, G, and B, since the peak width of the emission spectrum distribution by each phosphor is wide, a continuous distribution in which the respective peaks overlap each other. End up. For this reason, since other colors are mixed with the primary colors of blue, green, and red, it is difficult to display a clear color.

  Therefore, the illumination device 301 according to the present embodiment includes a wavelength cut filter 8 for cutting a band in which the wavelength distributions of light in R, G, and B components overlap. The wavelength cut filter 8 cuts light in a band where spectral distributions of transmission characteristics of the R, G, and B color filters overlap. For this reason, the wavelength distribution of light in each of the R, G, and B components becomes sharp, and the color purity of each color increases. Therefore, by using the lighting device 301 for a backlight device for liquid crystal display, a liquid crystal display having a wide color reproduction range and excellent color rendering can be realized without depending on the light emission characteristics of the LED element 1 and the phosphor 5. Can do.

  Among the three types of color filters R, G, and B, the R color filter has a characteristic of transmitting light in the wavelength range of 575 nm or more, and the G color filter transmits light in the wavelength range of about 475 nm to 620 nm. The B color filter has a characteristic of transmitting light in a wavelength range of about 380 nm to 550 nm. Therefore, in order to widen the color reproduction range and enhance the color rendering, the wavelength cut filter 8 has a wavelength range of approximately 580 nm to 610 nm where R and G overlap and a wavelength range of approximately 475 nm to 525 nm where G and B overlap. Is preferable, and it is more preferable to cut light in the wavelength ranges of 580 nm to 620 nm and 475 nm to 550 nm.

  The wavelength cut filter 8 may cut light in one of the wavelength ranges of the region where R and G overlap and the region where G and B overlap. It is preferable to cut the light.

  In the illumination device 301, a wavelength cut filter 8 for cutting light in a band where spectral distributions of transmission characteristics of the R, G, and B color filters overlap is provided on the surface of the transparent plate 4 facing outward. Yes. As a result, the wavelength distribution of light in each of the R, G, and B components becomes sharp, and the color purity of each color increases. Therefore, by using it in a backlight device for liquid crystal display or the like, a liquid crystal display having a wide color reproduction range and excellent color rendering can be realized without depending on the light emitting characteristics of the light emitting element and the fluorescent material.

  Since the operation of the lighting device 301 is substantially the same as that of the lighting device 101, description thereof is omitted.

(Embodiment 4)
A fourth embodiment of the present invention will be described in detail below with reference to FIG. However, the same members as those in the first to third embodiments described above are denoted by the same reference numerals, and the description thereof is omitted.

  In the second embodiment, the illumination device is formed with the same configuration as that of the second embodiment except that the shape of the recess in the package 3 is different.

  FIG. 6 is a cross-sectional view of the lighting apparatus according to the present embodiment.

  As shown in FIG. 6, the package 3 in the lighting device 401 is provided with a hemispherical recess from the upper surface toward the inside. For this reason, the distance from the LED element 1 to the side surface inside the recess of the package 3 to which the phosphor 5 is applied is substantially equal. Therefore, since the phosphor 5 can be excited more uniformly by the LED elements 1, it is possible to realize an illumination device with stable emission intensity and uniform emission directional characteristics.

  In this way, by changing the shape of the recess, it is possible to obtain the necessary directivity characteristics such as a type that increases the output at the center, a type that averages the overall output, a type that increases the output at the end, etc. Become.

  Since the operation of the lighting device 401 is substantially the same as that of the lighting device 101, description thereof is omitted.

(Embodiment 5)
A fifth embodiment of the present invention will be described below in detail with reference to FIG. However, the same reference numerals are given to the same members as those in the first to fourth embodiments, and the description thereof is omitted.

  In Embodiment 4, the illuminating device is formed with the same configuration as that of Embodiment 4 except that two LED elements are provided.

  FIG. 7 is a cross-sectional view of the lighting apparatus according to the present embodiment.

  As shown in FIG. 7, in the lighting device 501, the first LED element 12 and the second LED element 13 are installed on the surface of the transparent plate 4 on the concave side. Thereby, by combining with LED elements having the same light emission characteristics or LED elements having different light emission characteristics, light emission characteristics such as light intensity and light emission wavelength range can be freely adjusted. Therefore, arbitrary light emission characteristics can be obtained.

  Note that although the lighting device 501 has a configuration in which two light emitting elements are provided, the present invention is not limited to this. It is possible to install as many as possible in the package 3.

  As described above, the lighting device 501 includes a plurality of light-emitting elements inside the package. Thereby, the intensity | strength of light can be raised more. Accordingly, light emission characteristics with higher luminous intensity can be obtained.

  Since the operation of the lighting device 501 is substantially the same as that of the lighting device 101, description thereof is omitted.

(Embodiment 6)
The sixth embodiment of the present invention will be described below in detail with reference to FIG. However, the same members as those in the first to fifth embodiments described above are denoted by the same reference numerals, and the description thereof is omitted.

  In the first embodiment, a lighting device is formed with the same configuration as that of the first embodiment except that a resin reflector (package) 10 and a resin substrate (package) 11 are provided instead of the package 3. Has been.

  FIG. 8 is a cross-sectional view of the lighting apparatus according to the present embodiment.

  As shown in FIG. 8, the lighting device 601 includes a resin substrate 11 and a resin reflector 10 instead of a package.

  The resin substrate 11 has a flat plate shape whose bottom surface is larger than the bottom surface of the resin reflector 10, and the LED element 1 is mounted on the top surface.

  The resin reflector 10 has a shape in which a hole having a shape obtained by cutting the tip of a cone in parallel with the bottom surface is penetrated from a top surface toward the bottom surface in a substantially rectangular column having a square bottom surface. The holes on the top surface and the bottom surface are provided so as to be the centers of the respective surfaces, and the holes on the top surface are larger than the bottom surface.

  The LED element 1 is installed on a resin substrate 11. The resin reflector 10 is installed on the surface of the resin substrate 11 on which the LED is installed so that the lower surface is in contact with the resin substrate 11. At this time, the LED element 1 is stored in a through hole of the resin reflector 10. Similar to the illumination device 101, the ultraviolet cut filter 6 and the transparent plate 4 are installed on the upper surface of the resin reflector 10.

  The illumination device 601 can be manufactured at a lower cost because the package is manufactured from an inexpensive resin as a package material as described above.

  Since the operation of the lighting device 601 is substantially the same as that of the lighting device 101, description thereof is omitted.

(Embodiment 7)
The seventh embodiment of the present invention will be described in detail below with reference to FIG. However, the same reference numerals are given to the same members as those in the first to sixth embodiments, and the description thereof is omitted.

  FIG. 9 is a cross-sectional view of the lighting apparatus according to the present embodiment.

  In the present embodiment, the illumination device 701 is formed with the same configuration as that of the sixth embodiment except that the lead frame 72 is provided on the surface of the resin substrate 11 on which the LED element 1 is mounted. ing.

  Since the lighting device 701 is provided with the lead frame 72 on the surface of the resin substrate 11 on which the LED element 1 is mounted, it is not necessary to separately provide wiring for driving the LED element 1. For this reason, an illuminating device can be manufactured at an even lower cost.

  Since the operation of the lighting device 701 is substantially the same as that of the lighting device 101, description thereof is omitted.

(Embodiment 8)
The eighth embodiment of the present invention will be described in detail below with reference to FIGS. However, the same reference numerals are given to the same members as those in the first to seventh embodiments, and the description thereof is omitted.

  Except that the second transparent plate (second transparent member) 9 is provided, the illumination device is formed in the same configuration as that of the third embodiment.

  FIG. 10 is a cross-sectional view of the lighting apparatus according to the present embodiment. FIG. 11 is a perspective view showing a schematic configuration of the lighting apparatus according to the present embodiment.

  As shown in FIGS. 10 and 11, the illumination device 801 is further provided with a second transparent plate 9 on the wavelength cut filter 8. The second transparent plate 9 has the same shape as the transparent plate 4.

  In the illumination device 801, the second transparent plate 9 is installed on the wavelength cut filter 8. Thereby, the wavelength cut filter 8 provided on the transparent plate 4 can be protected from the outside. Further, another filter or the like can be provided on the outer surface of the second transparent plate 9. Therefore, the durability of the wavelength cut filter 8 can be further increased, and the characteristics of the emitted light can be further changed.

  Since the operation of the lighting device 801 is substantially the same as that of the lighting device 101, description thereof is omitted.

(Embodiment 9)
A ninth embodiment of the present invention will be described below in detail with reference to FIGS. However, the same reference numerals are given to the same members as those in the first to eighth embodiments described above, and the description thereof is omitted.

  In the first embodiment, the illumination device has the same configuration as that of the first embodiment except that the concave portion is filled with a fluorescent substance-containing transparent resin (transparent resin containing a fluorescent substance) 14 instead of the phosphor 5. A device is formed.

  FIG. 12 is a cross-sectional view of the lighting apparatus according to the present embodiment. FIG. 13 is a cross-sectional view cut in a direction perpendicular to the surface of the package in which the opening of the recess is provided through the center of the lighting device before the transparent plate is installed in FIG.

  As shown in FIG. 12, in the illumination device 901, the fluorescent material-containing transparent resin 14 is filled in the concave portion of the package 3. The fluorescent substance-containing transparent resin 14 is obtained by dispersing three kinds of fluorescent substances that are excited by ultraviolet light and emit light of R, G, and B, respectively, in the transparent resin.

  Examples of the transparent resin contained in the fluorescent substance-containing transparent resin 14 include resins that are optically transparent with respect to light in the visible region, and include silicon resins and epoxy resins.

  In the lighting device 901, the fluorescent material-containing transparent resin 14 is filled in the package 3. This eliminates the need to apply the fluorescent material to the inner surface of the package, facilitating the application of the fluorescent material in the manufacturing process of the lighting device. That is, as shown in FIG. 13, after the LED element 1 is installed on the bottom surface of the recess of the package 3, the recess is filled with the fluorescent substance-containing transparent resin 14, and the ultraviolet cut filter 6 is placed on the opening of the package 3. The lighting device 801 can be manufactured by installing the transparent plate 4. Therefore, the lighting device can be manufactured more easily.

  Since the operation of the lighting device 901 is substantially the same as that of the lighting device 101, description thereof is omitted.

(Embodiment 10)
A tenth embodiment of the present invention will be described below in detail with reference to FIG. However, the same reference numerals are given to the same members as those in the first to ninth embodiments, and the description thereof is omitted.

  In the ninth embodiment, an illumination device is formed with the same configuration as that of the ninth embodiment except that a wavelength cut filter (second wavelength cut filter) 8 is further provided on the transparent plate 4. Yes.

  FIG. 14 is a cross-sectional view of the lighting apparatus according to the present embodiment.

  As shown in FIG. 14, in the illumination device 1001, the wavelength cut filter 8 for cutting light in a band in which the spectral distributions of the transmission characteristics of the R, G, and B color filters overlap each other faces the outside of the transparent plate 4. It is provided on the surface. As a result, the wavelength distribution of light in each of the R, G, and B components becomes sharp, and the color purity of each color increases. Therefore, by using it in a backlight device for liquid crystal display or the like, a liquid crystal display having a wide color reproduction range and excellent color rendering can be realized without depending on the light emitting characteristics of the light emitting element and the fluorescent material.

  Since the operation of the lighting device 1001 is substantially the same as that of the lighting device 101, description thereof is omitted.

(Embodiment 11)
The eleventh embodiment of the present invention will be described in detail below with reference to FIGS. 15 and 16. However, the same members as those in Embodiments 1 to 10 described above are denoted by the same reference numerals, and the description thereof is omitted.

  FIG. 15 is a cross-sectional view of the backlight device according to the present embodiment. FIG. 16 is a perspective view showing a schematic configuration of the backlight device according to the present embodiment.

  Note that the backlight device refers to an illumination device including a plurality of the above-described illumination devices, and is not limited to a backlight device for a liquid crystal display device.

  As shown in FIGS. 15 and 16, the backlight device 1101 has 13 lighting devices formed on one transparent plate 4. The transparent plate 4 has a flat plate shape with a rectangular bottom surface, and on the bottom surface, four, five, four, and three rows from the end are arranged in the long side direction so that the illumination devices are substantially equally spaced from each other. Is arranged. The configuration of each lighting device is the same as that of the lighting device 401 according to the fourth embodiment, and the side of each package 3 and the side of the transparent plate 4 are parallel when viewed from the upper surface of the transparent plate 4. It is arranged.

  As described above, since the backlight device 1101 includes the lighting device according to this embodiment, a backlight device with higher light emission efficiency and lower power consumption can be provided. In addition, since a plurality of the lighting devices are arranged on one transparent plate 4, it is not necessary to use a separate wiring board or the like by arranging electric wiring on the transparent plate 4. Thereby, since the number of components can be reduced, a backlight apparatus can be manufactured at lower cost.

  Since the operation of the backlight device 1101 is substantially the same as that of the lighting device 101, description thereof is omitted.

(Embodiment 12)
A twelfth embodiment of the present invention will be described below in detail with reference to FIG. However, the same members as those in the first to eleventh embodiments described above are denoted by the same reference numerals, and the description thereof is omitted.

  FIG. 17 is a cross-sectional view of the backlight device according to this embodiment.

  In the present embodiment, the configuration of the plurality of lighting devices provided in the backlight device 1101 is substantially the same as that of the lighting device 101 of the first embodiment, but is the same as that of the eleventh embodiment. In the configuration, a backlight device 1201 is formed. However, in the plurality of illumination devices provided in the backlight device 1201, unlike the illumination device 101, the ultraviolet cut filter 6 is not provided in the package 3, and the ultraviolet cut filter 6 is integrated with the transparent plate 4. It has become.

  As shown in FIG. 17, a wiring board (wiring) 75 is provided on the surface of the transparent plate 4 on which the package 3 is provided, and a wavelength cut filter 8 is provided on the surface opposite to the above surface. . The wavelength cut filter 8 has a plate shape having a bottom surface having substantially the same area as the transparent plate 4, and is provided so that the transparent plate 4 and the bottom surface of each other are aligned.

  The wiring board 75 is provided with a hole having substantially the same size as the opening of the package 3 in order to allow light emitted from the phosphor 5 in the package 3 to pass therethrough. The wiring board 75 is provided with a number of holes corresponding to each of the plurality of lighting devices. Each of the holes provided in the wiring substrate 75 is provided with an ultraviolet cut filter 6. The LED element 1 disposed in the package 3 is fixed to the wiring board 75 by solder 25.

  Since the operation of the backlight device 1201 is substantially the same as that of the lighting device 101, description thereof is omitted.

(Embodiment 13)
A thirteenth embodiment of the present invention will be described below in detail with reference to FIGS. However, the same members as those in Embodiments 1 to 12 described above are denoted by the same reference numerals, and the description thereof is omitted.

  FIG. 18 is a cross-sectional view of the backlight device according to the present embodiment. FIG. 19 is a perspective view showing a schematic configuration of the backlight device according to the present embodiment.

  As shown in FIGS. 18 and 19, the backlight device 1301 has 13 lighting devices formed on one transparent plate 4 in the same manner as the backlight device 1101, but the respective packages 3 are connected to each other. It differs in that it is a thing. Therefore, the package 3 has a flat plate shape with a rectangular bottom surface, and hemispherical concave portions are arranged at substantially equal intervals on the upper surface in four rows, five rows, four rows and three rows from the end in the long side direction. It is arranged to become.

  Thereby, since the several recessed part is provided in one package, the man-hour in manufacture can be reduced rather than providing one recessed part in one package.

  Since the operation of the backlight device 1301 is substantially the same as that of the lighting device 101, the description thereof is omitted.

  In the above description, the case where the range of light emitted from the LED element is an ultraviolet light emitting LED element in the ultraviolet region has been described, but the present invention is not limited to this. If the wavelength cut filter is made to correspond to the wavelength range of light emitted from the LED element, it may emit light in the visible region such as a blue light emitting LED element. If the LED element is a blue light emitting LED element, substantially the same effect as in the present embodiment can be obtained.

  In the above description, the case where the phosphor and the fluorescent substance-containing transparent resin contain three types of fluorescent substances has been described. However, the present invention is not limited to this. There may be one kind of substance that emits three colors of R, G, and B, or a plurality of substances may be used for the same color. Even with the phosphor configured as described above, substantially the same effect as in the present embodiment can be obtained.

  In the above description, the backlight device in which 13 lighting devices are formed on the transparent plate is described as an example, but the present invention is not limited to this. If there are a plurality of illumination devices, substantially the same effect as the present embodiment can be obtained.

  The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope shown in the claims, and embodiments obtained by appropriately combining technical means disclosed in different embodiments. Is also included in the technical scope of the present invention.

  As described above, the illumination device of the present invention includes the wavelength cut filter for reflecting the light emitted from the light emitting element. Therefore, a lighting device with higher luminous efficiency can be provided. Therefore, the illumination device of the present invention can be suitably used for a light source device such as a liquid crystal backlight light source or an illumination light source. Therefore, the lighting device of the present invention can be suitably used in various fields of electrical products from homes to industrial facilities.

It is sectional drawing of the illuminating device which concerns on this Embodiment. It is a perspective view which shows schematic structure of the said illuminating device. It is sectional drawing of the illuminating device which concerns on the other form of this Embodiment. It is sectional drawing which shows the principal part structure in the surface of the transparent plate of the said illuminating device. It is sectional drawing of the illuminating device which concerns on the further another form of this Embodiment. It is sectional drawing of the illuminating device which concerns on the further another form of this Embodiment. It is sectional drawing of the illuminating device which concerns on the further another form of this Embodiment. It is sectional drawing of the illuminating device which concerns on the further another form of this Embodiment. It is sectional drawing of the illuminating device which concerns on the further another form of this Embodiment. It is sectional drawing of the illuminating device which concerns on the further another form of this Embodiment. It is a perspective view which shows schematic structure of the illuminating device of FIG. It is sectional drawing of the illuminating device which concerns on the further another form of this Embodiment. It is sectional drawing of the illuminating device before the transparent board fixation of FIG. It is sectional drawing of the illuminating device which concerns on the further another form of this Embodiment. It is sectional drawing of the backlight apparatus which concerns on this Embodiment. FIG. 16 is a perspective view illustrating a schematic configuration of the backlight device of FIG. 15. It is sectional drawing which shows schematic structure of the backlight apparatus which concerns on the other form of this Embodiment. It is sectional drawing of the backlight apparatus which concerns on the further another form of this Embodiment. It is a perspective view which shows schematic structure of the backlight apparatus of FIG.

Explanation of symbols

1 LED element (light emitting element)
3 Package 4 Transparent plate (transparent material)
5 Fluorescent substance (fluorescent substance)
6 Ultraviolet cut filter (wavelength cut filter)
8 wavelength cut filter (second wavelength cut filter)
9 Second transparent plate (second transparent member)
12 1st LED element (light emitting element)
13 Second LED element (light emitting element)
14 Transparent resin-containing transparent resin (transparent resin containing fluorescent material)
15 Wiring (electrical wiring)
101 Illumination Device 1001 Backlight Device

Claims (16)

A light emitting element that emits light including at least a component other than the visible region;
A fluorescent substance that emits light in the visible region when excited by light emitted from the light emitting element;
The light emitting device and the fluorescent material are disposed inside, and a package is formed with an opening for emitting the light emitted from the light emitting device and the light emitted from the fluorescent material to the outside. In the lighting device
A lighting device, wherein a wavelength cut filter that reflects light outside the visible region emitted from the light emitting element is provided in an opening of the package.   The lighting device according to claim 1, wherein the package is provided with a recess for arranging the light emitting element and the fluorescent substance therein.   The lighting device according to claim 1, wherein a transparent member for closing the opening of the package is installed on a surface of the package where the opening is formed.   The lighting device according to claim 3, wherein the transparent member has a flat plate shape.   The lighting device according to claim 3, wherein the wavelength cut filter is installed on a surface of the transparent member facing the inside of the package.   The lighting device according to claim 3, wherein the transparent member is integrated with the wavelength cut filter. Furthermore, electrical wiring for electrically connecting the light emitting element to external power is provided on the surface of the transparent member,
The lighting device according to claim 4, wherein the light emitting element is installed on a surface of the transparent member facing the inside of the package.   The electrical wiring is characterized in that a width in a direction perpendicular to a surface on which the opening of the package is provided is wider than a width in a horizontal direction on a surface on which the opening of the package is provided. The lighting device according to claim 7. An illumination device mounted on a liquid crystal display device including a plurality of color filters,
2. The illumination according to claim 1, wherein a second wavelength cut filter for cutting light in a band in which spectral distributions of transmission characteristics of the color filters of the respective colors overlap with each other is provided in the opening of the package. apparatus.   The lighting device according to claim 1, wherein the package is filled with a transparent resin containing the fluorescent material.   The illumination device according to claim 1, wherein the light emitted from the light emitting element is light in an ultraviolet region.   The lighting device according to claim 1, wherein the package is made of ceramic.   The lighting device according to claim 1, wherein a plurality of the light emitting elements are provided inside the package.   Furthermore, the 2nd transparent member is provided on the 2nd wavelength cut filter, The illuminating device of Claim 9 characterized by the above-mentioned. In the backlight device comprising the illumination device according to claim 1,
A backlight device, wherein a plurality of the lighting devices are arranged on a transparent member.   A liquid crystal display device comprising the backlight device according to claim 15.

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