JP2014167974A - Screening method of fluorescent materials and light-emitting apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a screening method of fluorescent materials capable of obtaining a high luminous flux fluorescent material and to provide a light-emitting apparatus formed by using the fluorescent material selected by the same.SOLUTION: The screening method of fluorescent materials related to one embodiment of the present invention includes steps of: measuring emission spectra of fluorescent materials; and screening from the fluorescent materials one whose emission center of gravity wavelength λof the emission spectra is 530nm or more and 570nm or less and a full width at half maximum is 90 nm or less.

Description

  The present invention relates to a phosphor selection method and a light emitting device.

  As a conventional light-emitting device, a light-emitting device that includes an LED chip and a phosphor and that uses fluorescence emitted from the phosphor by absorbing light emitted from the LED chip is known (for example, see Patent Document 1).

JP 2012-99863 A

  One of the objects of the present invention is to form a phosphor selection method capable of obtaining a phosphor having a high luminous flux, and a phosphor selected by the method, in order to form a light emitting device having a higher luminous flux. It is to provide a light emitting device.

ただし、上記数式（１）において、λは波長を表し、P(λ)は波長の関数として表される前記蛍光体の発光強度を表す。 In order to achieve the above object, in one embodiment of the present invention, a step of measuring an emission spectrum of a phosphor, and an emission center-of-gravity wavelength λ _C represented by the following formula (1) of the emission spectrum from the phosphor is 530 nm. And a step of selecting those having a full width at half maximum of 90 nm or less.

However, in the above formula (1), λ represents a wavelength, and P (λ) represents the emission intensity of the phosphor expressed as a function of the wavelength.

  In another aspect of the present invention, the LED chip mounted on the substrate, the sealing material installed on the LED chip, and the above-described phosphor selection method included in the sealing material are selected. And a phosphor.

  In the light emitting device, the LED chip, the sealing material, the first fluorescent part having the phosphor, the second LED chip mounted on the second base, and the second LED chip A second fluorescent part having a second phosphor that is installed, and a second phosphor having a light emission wavelength longer than that of the phosphor, which is included in the second sealant, and The first light emitting unit and the second light emitting unit may be arranged side by side in the horizontal direction.

  In the light emitting device, a second sealing material installed under the sealing material, and a second phosphor having a light emission wavelength longer than that of the phosphor included in the second sealing material. Furthermore, you may have.

  The light emitting device may include the LED chip, the sealing material, and a fluorescent portion having the phosphor, and a lamp having a longer emission wavelength than the phosphor.

  ADVANTAGE OF THE INVENTION According to this invention, the light-emitting device formed using the fluorescent substance selection method which can obtain the fluorescent substance of a high luminous flux, and the fluorescent substance selected by the method can be provided.

FIG. 1 is a vertical cross-sectional view of the light emitting device according to the first embodiment. 2A is a graph showing the relationship between the emission center-of-gravity wavelength λ _c and the luminous flux ratio of the phosphors described in Table 1, and FIG. 2B is the half width of the phosphor described in Table 1. FIG. 2C is a graph showing the relationship between the emission center-of-gravity wavelength λ _c of the phosphors shown in Table 1 and the half-value width. FIG. 3 is a graph showing the emission spectra of the high light flux device and the low light flux device described in Table 2 and the photopic standard relative luminous sensitivity. FIG. 4 is a graph showing the emission spectrum of the phosphor according to the first embodiment and the excitation spectrum of the red phosphor ((Ca, Sr) AlSN ₃ : Eu). FIG. 5A is a vertical sectional view of the light emitting device according to the second embodiment, and FIGS. 5B and 5C are vertical sectional views of modifications thereof. FIG. 6 is a vertical cross-sectional view of the light emitting device according to the third embodiment. FIG. 7A is a vertical sectional view of the light emitting device according to the fourth embodiment, and FIG. 7B is a vertical sectional view of a modification thereof. FIG. 8 is a vertical sectional view of the light emitting device according to the fifth embodiment. FIG. 9 is a vertical sectional view of the light emitting device according to the sixth embodiment. FIG. 10 is a chromaticity diagram illustrating the chromaticity of the light emitting unit and the lamp according to the sixth embodiment.

[First Embodiment]
FIG. 1 is a vertical cross-sectional view of the light emitting device according to the first embodiment. The light emitting device 10 includes a case 11, a base 12 included in the case 11, an LED chip 13 mounted on the base 12 in the recess of the case 11, and a seal that seals the LED chip 13 in the recess of the case 11. It has a stopper 14.

  The LED chip 13 includes, for example, a chip substrate and a crystal layer including a light emitting layer and a clad layer sandwiching the light emitting layer. The LED chip 13 may be a face-up type LED chip with the crystal layer facing upward, or a face-down type LED chip with the crystal layer facing downward.

  The case 11 has an annular side wall that forms the side wall of the recess, and the LED chip 13 is mounted in a region surrounded by the side wall. The inner surface of the case 11 functions as a reflecting member that reflects the light emitted from the LED chip 13.

  The case 11 is made of, for example, a thermoplastic resin such as polyphthalamide resin, LCP (Liquid Crystal Polymer), or PCT (Polycyclohexylene Dimethylene Terephalate), or a thermosetting resin such as silicone resin, modified silicone resin, epoxy resin, or modified epoxy resin. Become. The case 11 may include light reflecting particles such as titanium dioxide for improving the light reflectance.

  The base body 12 is, for example, a lead frame insert board in which a lead frame, a wiring board, or a conductor frame is molded and insulated with a resin. The LED chip 13 and the base 12 are electrically connected by a wire, a conductive bump or the like (not shown).

  The sealing material 14 is made of, for example, a resin material such as a silicone resin or an epoxy resin, or glass. Further, the sealing material 14 includes a particulate phosphor 15. For example, when the emission color of the LED chip 13 is blue and the fluorescence color of the phosphor 15 is yellow, the emission color of the light emitting device 10 is white. The phosphors 15 may be dispersedly arranged in the sealing material 14 or may be settling.

  The sealing material 14 may be formed above the LED chip 13 and separated from the LED chip 13.

(Characteristics of phosphor)
The phosphor 15 has an emission center-of-gravity wavelength λ _c of an emission spectrum of 530 nm to 570 nm and a half width of 90 nm or less. Here, the emission center-of-gravity wavelength λ _c is a wavelength represented by the following formula (2).

  In the above formula (2), λ represents the wavelength, and P (λ) represents the emission intensity of the phosphor 15 expressed as a function of the wavelength, that is, the emission spectrum of the phosphor 15.

By measuring the emission spectra of a plurality of types of phosphors, and selecting the phosphors satisfying the above-mentioned emission center-of-gravity wavelength λ _c and half-value width from the plurality of types of phosphors based on the obtained measurement results, 15 is obtained.

Emission centroid wavelength lambda _c is a wavelength, such as spectral area of spectrum area and a short wavelength side of the long wavelength side of the wavelength lambda _c of the emission spectrum is equal. As the emission center-of-gravity wavelength λ _c is closer to the wavelength 555 nm at which the standard relative luminous sensitivity V (λ) in the bright place is maximum, the emission spectrum P (λ) overlaps with the standard relative luminous sensitivity V (λ) in the bright place. Increases, and the luminous flux Φ proportional to the overlap integral value of the emission spectrum P (λ) and the standard relative luminous sensitivity V (λ) increases. The luminous flux Φ is expressed by the following formula (3).

In the above mathematical formula (3), K _m represents the maximum visibility (683 [lm / W]), and Φ _e (λ) represents the radiant flux.

  In addition, the emission spectrum of the phosphor has a sharp overlap with the standard relative luminous sensitivity V (λ) in the bright place is larger in the sharp spectrum with a small half-value width than in a gentle spectrum with a large half-value width. The luminous flux Φ increases.

(Evaluation of phosphor)
Table 1 below shows the emission peak wavelengths λ _p , emission centroid wavelengths λ _c , half-value widths, and luminous flux ratios of nine phosphors. Here, the emission peak wavelength λ _p and the full width at half maximum are obtained by measuring the emission spectrum of the phosphor, and the emission center-of-gravity wavelength λ _c is calculated from the emission spectrum using the above equation (2). It is a thing.

  The luminous flux ratio in Table 1 is the ratio of luminous flux to the reference when the luminous flux of the uppermost phosphor (No. 1) in Table 1 is used as a reference. The luminous flux is obtained by simulation assuming that all of the light emitted from the blue LED chip having an output of 25 mW and a main wavelength of 450 nm is color-converted by the phosphor (conversion efficiency 100%).

FIG. 2A is a graph showing the relationship between the emission center-of-gravity wavelength λ _c and the luminous flux ratio of the phosphors described in Table 1. In FIG. The values of BOS (barium orthosilicate) phosphors 1 to 6 are marked with “♦”, The values of 7-9 YAG (yttrium, aluminum, garnet) phosphors are represented by the mark “■”.

FIG. 2A shows a correlation between the emission centroid wavelength λ _c and the luminous flux. When the emission centroid wavelength λ _c is in the range of approximately 530 nm to 570 nm, the luminous flux increases, and the emission centroid wavelength λ _c is approximately It shows that the luminous flux is particularly large when it is in the range of 535 nm or more and 565 nm or less. The numerical range of the emission center-of-gravity wavelength λ _c includes a wavelength 555 nm at which the standard relative luminous sensitivity V (λ) in a bright place takes a maximum value.

  FIG. 2B is a graph showing the relationship between the half-value width of the phosphors described in Table 1 and the luminous flux ratio. In FIG. The values of BOS phosphors 1 to 6 are marked with “♦”, No. The values of YAG phosphors 7 to 9 are represented by the mark “■”.

  FIG. 2B shows a correlation between the full width at half maximum and the light beam. The light beam becomes large when the half width is in the range of about 90 nm or less, and the light beam is particularly large when the half width is in the range of about 80 nm or less. It shows that it becomes.

FIG. 2C is a graph showing the relationship between the emission center-of-gravity wavelength λ _c and the half-value width of the phosphors described in Table 1. In FIG. 1 is marked with a mark “●”, a phosphor value with a luminous flux ratio of 1.0 or more is marked with “◯”, and a phosphor value with a luminous flux ratio of less than 1.0 is marked with “X”. Represented by

  The area delimited by the dotted line in FIG. This is a high luminous flux region that is set so that the luminous flux ratio of 3 to 6 includes a value of a phosphor of 1.0 or more.

Table 2 below shows the characteristics of the light emitting device formed using each of the four types of phosphors. “Phosphor characteristics” in Table 2 represents the characteristics of the phosphor used in the light emitting device, and “Light emitting apparatus characteristics” represents the characteristics of the light emitting device. The emission peak wavelength λ _p of “phosphor characteristic” represents the wavelength of the peak closest to the wavelength 555 nm at which the standard relative luminous sensitivity V (λ) takes the maximum value.

No. in Table 2 The high luminous flux devices 1 and 2 are phosphors that satisfy the conditions of the present embodiment, that is, fluorescent light whose emission center-of-gravity wavelength λ _c of the emission spectrum is not less than 530 nm and not more than 570 nm, and the half width is not more than 90 nm. A light emitting device including a body. No. The low luminous flux devices 1 and 3 are light emitting devices including phosphors that do not satisfy the conditions of the present embodiment.

  The high luminous flux devices 1 and 2 and the low luminous flux devices 1 and 2 have the same configuration as that of the light emitting device 10 according to the present embodiment, and include blue LEDs as LED chips.

  The luminous flux ratio in Table 2 is the ratio of luminous flux to the reference when the luminous flux of the low luminous flux device 1 (No. 3) in Table 2 is used as a reference.

  FIG. 3 is a graph showing the emission spectra of the high light flux devices 1 and 2 and the low light flux devices 1 and 2 shown in Table 2 and the photopic standard relative luminous sensitivity.

  Table 2 shows that the luminous flux of the high luminous flux devices 1 and 2 including the phosphor that satisfies the conditions of the present embodiment is larger than the luminous flux of the low luminous flux devices 1 and 2 including the phosphor that does not satisfy the conditions of the present embodiment. It is shown that.

[Second Embodiment]
The second embodiment is different from the first embodiment in the configuration of the light emitting device. Note that the description of the same points as in the first embodiment will be omitted or simplified.

  In the light emitting device including the phosphor 15 according to the first embodiment, a high luminous flux is obtained. However, when a phosphor having a longer emission wavelength than that of the phosphor 15 is mixed, light emitted from the phosphor 15 emits light. It is absorbed by the phosphor having a long wavelength, and the light extraction efficiency is lowered.

  For example, according to the evaluation result of the phosphor described in Table 1 of the first embodiment, the emission color of the phosphor satisfying the condition of the phosphor 15 according to the first embodiment is yellow green to green. There is a tendency that a phosphor having a yellow emission color does not satisfy the condition. For this reason, when a white, particularly reddish, warm white light emitting device is formed using the phosphor 15, a red phosphor is used in addition to the blue LED and the phosphor 15. In this case, since the red phosphor has a longer emission wavelength than the phosphor 15, the red phosphor absorbs light emitted from the phosphor 15.

FIG. 4 is a graph showing the emission spectrum of the phosphor 15 according to the first embodiment and the excitation spectrum of the red phosphor ((Ca, Sr) AlSN ₃ : Eu).

  FIG. 4 shows that the emission spectrum of the phosphor 15 used in the high luminous flux device 1 largely overlaps with the excitation spectrum of the red phosphor. From this, the emission of the phosphor 15 is absorbed by the red phosphor. You can see that

(Configuration of light emitting device)
FIG. 5A is a vertical cross-sectional view of the light emitting device according to the second embodiment. The light emitting device 20a includes a light emitting unit 201 and a light emitting unit 202 arranged side by side in the horizontal direction. The light emitting unit 201 and the light emitting unit 202 are installed on the base 26.

  The light emitting unit 201 has the same configuration as the light emitting device 10 of the first embodiment. That is, the light emitting unit 201 seals the case 11, the base 12 included in the case 11, the LED chip 13 mounted on the base 12 in the recess of the case 11, and the LED chip 13 in the recess of the case 11. The sealing material 14 includes a phosphor 15.

  The light emitting unit 202 is different from the light emitting unit 201 in that the phosphor 25 is included in the sealing material 14 instead of the phosphor 15.

The phosphor 15 included in the light emitting unit 201 is the phosphor according to the first embodiment, and the emission center-of-gravity wavelength λ _c of the emission spectrum is not less than 530 nm and not more than 570 nm, and the half width is not more than 90 nm.

  The phosphor 25 included in the light emitting unit 202 is a phosphor having a longer emission wavelength than the phosphor 15. For example, when the emission color of the phosphor 15 is green or yellowish green, a phosphor having a red emission color is used as the phosphor 25. In this case, if the LED chip 13 is a blue LED chip, the light emission color of the light emitting device 20a is white due to the color mixture of the light emission parts 201 and 202.

  In the light emitting device 20 a, the light emitted from the phosphor 15 in the light emitting unit 201 does not enter the light emitting unit 202 directly. For this reason, the fall of the light extraction efficiency of the light-emitting device by the light emitted from the fluorescent substance 15 being absorbed by the fluorescent substance 25 can be suppressed.

  FIG. 5B is a vertical cross-sectional view of a modification of the light emitting device according to the second embodiment. The light emitting device 20b is formed such that the light emitting unit 201, the case 11 of the light emitting unit 202, and the base 12 are integrated.

  Also in the light emitting device 20 b, the light emitted from the phosphor 15 in the light emitting unit 201 does not directly enter the light emitting unit 202. For this reason, the fall of the light extraction efficiency of the light-emitting device by the light emitted from the fluorescent substance 15 being absorbed by the fluorescent substance 25 can be suppressed.

  FIG. 5C is a vertical cross-sectional view of another modified example of the light emitting device according to the second embodiment. The light emitting device 20 c is different from the light emitting device 20 b in that it has a case 21 instead of the case 11. The case 21 has a shape in which a portion at the boundary between the light emitting unit 201 and the light emitting unit 202 of the case 11 is removed.

  In the light emitting device 20c, the direction of light emitted from the phosphor 15 in the light emitting unit 201 and entering the light emitting unit 202 is limited to a part of the horizontal direction. For this reason, the fall of the light extraction efficiency of the light-emitting device by the light emitted from the fluorescent substance 15 being absorbed by the fluorescent substance 25 can be suppressed.

[Third Embodiment]
The third embodiment is different from the first and second embodiments in the configuration of the light emitting device. Note that description of the same points as in the first and second embodiments is omitted or simplified.

(Configuration of light emitting device)
FIG. 6 is a vertical cross-sectional view of the light emitting device according to the third embodiment. The light emitting device 30 includes a light emitting unit 301 and a light emitting unit 302 that are arranged side by side in the horizontal direction. The light emitting units 301 and the light emitting units 302 are preferably arranged alternately as shown in FIG.

  The light emitting unit 301 includes an LED chip 13 connected to the base 31 and a dome-shaped sealing material 32 that seals the LED chip 13. The sealing material 32 includes the phosphor 15.

  The light emitting unit 302 is different from the light emitting unit 301 in that the phosphor 25 is included in the sealing material 32 instead of the phosphor 15.

  The sealing material 32 is made of the same material as the sealing material 14 of the first embodiment.

  In the light emitting device 30, light emitted upward and obliquely upward from the phosphor 15 in the light emitting unit 301 does not directly enter the light emitting unit 302. For this reason, the fall of the light extraction efficiency of the light-emitting device by the light emitted from the fluorescent substance 15 being absorbed by the fluorescent substance 25 can be suppressed.

[Fourth Embodiment]
The fourth embodiment differs from the first and second embodiments in the configuration of the light emitting device. Note that description of the same points as in the first and second embodiments is omitted or simplified.

(Configuration of light emitting device)
FIG. 7A is a vertical sectional view of the light emitting device according to the fourth embodiment. The light emitting device 40 a includes a case 11, a base 12 included in the case 11, an LED chip 13 mounted on the base 12 in the recess of the case 11, and a seal that seals the LED chip 13 in the recess of the case 11. It has a stopper 14 a, an intermediate layer 41 on the sealing material 14 a in the recess of the case 11, and a sealing material 14 b on the intermediate layer 41 in the recess of the case 11. The sealing material 14 a includes the phosphor 25, and the sealing material 14 b includes the phosphor 15.

  In the light emitting device 40a, the sealing material 14a including the phosphor 25 and the sealing material 14b including the phosphor 15 are separated by the intermediate layer 41, and light emitted upward and laterally from the phosphor 15 is emitted. It does not go directly to the phosphor 25. For this reason, the fall of the light extraction efficiency of the light-emitting device by the light emitted from the fluorescent substance 15 being absorbed by the fluorescent substance 25 can be suppressed.

  FIG. 7B is a vertical cross-sectional view of a modified example of the light emitting device according to the fourth embodiment. In the light emitting device 40b, the plate 42 including the phosphor 15 is formed on the case 11, that is, outside the concave portion of the case 11. The plate 42 is a plate-like member made of glass or resin.

  Also in the light emitting device 40b, the sealing material 14a including the phosphor 25 and the plate 42 including the phosphor 15 are separated by the intermediate layer 41, and light emitted upward and laterally from the phosphor 15 is phosphor. There is no direct heading to 25. For this reason, the fall of the light extraction efficiency of the light-emitting device by the light emitted from the fluorescent substance 15 being absorbed by the fluorescent substance 25 can be suppressed.

[Fifth Embodiment]
The fifth embodiment is different from the first and second embodiments in the configuration of the light emitting device. Note that description of the same points as in the first and second embodiments is omitted or simplified.

(Configuration of light emitting device)
FIG. 8 is a vertical sectional view of the light emitting device according to the fifth embodiment. The light emitting device 50 includes a case 11, a base 12 included in the case 11, an LED chip 13 mounted on the base 12 in the recess of the case 11, and a seal that seals the LED chip 13 in the recess of the case 11. It has a stop material 14 a and a sealing material 14 b on the sealing material 14 a in the recess of the case 11. The sealing material 14 a includes the phosphor 25, and the sealing material 14 b includes the phosphor 15.

  In the light emitting device 50, since the fluorescent material 25 is disposed in the sealing material 14a, the fluorescent material 15 and the fluorescent material 25 are separated, and light emitted upward and laterally from the fluorescent material 15. Does not go directly to the phosphor 25. For this reason, the fall of the light extraction efficiency of the light-emitting device by the light emitted from the fluorescent substance 15 being absorbed by the fluorescent substance 25 can be suppressed.

[Sixth Embodiment]
The sixth embodiment is different from the first embodiment in the configuration of the light emitting device. Note that the description of the same points as in the first embodiment will be omitted or simplified.

(Configuration of light emitting device)
FIG. 9 is a vertical sectional view of the light emitting device according to the sixth embodiment. The light emitting device 60 includes a case 61, a light emitting unit 62 mounted in the recess of the case 61, and a lamp 63 mounted in the recess of the case 61.

  The light emitting unit 62 has the same configuration as the light emitting device 10 of the first embodiment. That is, the light emitting unit 62 seals the case 11, the base 12 included in the case 11, the LED chip 13 mounted on the base 12 in the recess of the case 11, and the LED chip 13 in the recess of the case 11. The sealing material 14 includes a phosphor 15.

  The lamp 63 is a lamp having an emission wavelength longer than that of the phosphor 15 included in the light emitting unit 62. For example, when the emission color of the phosphor 15 is green or yellowish green, a lamp whose emission color is orange such as a sodium lamp is used as the lamp 63. In this case, if the LED chip 13 of the light emitting unit 62 is a blue LED chip, the light emission color of the light emitting device 60 becomes white due to the color mixture of the light emission colors of the light emitting unit 62 and the lamp 63.

  Since the light emitting device 60 uses the lamp 63 instead of the phosphor in order to emit light having a longer wavelength than the light emitted from the phosphor 15, the light emitted from the phosphor 15 has an emission wavelength that is greater than that of the phosphor 15. A decrease in light extraction efficiency of the light-emitting device due to absorption by a long phosphor can be suppressed.

FIG. 10 is a chromaticity diagram illustrating the chromaticity of the light emitting unit and the lamp according to the sixth embodiment. The mark “Δ” in FIG. 10 represents the chromaticity of the light emitting unit 62 including the phosphor 15 having the emission center of gravity wavelength λ _C of 558 nm, and the mark “◇” represents the phosphor 15 having the emission center of gravity wavelength λ _C of 545 nm. The mark “■” represents the chromaticity of the lamp 63 which is a sodium lamp.

  FIG. 10 shows chromaticity ranges of daylight color, daylight white color, and light bulb color, which are standardized by JISZ9112. In FIG. 10, the chromaticity of the light emitting unit 62 and the chromaticity of the lamp 63 are plotted at positions sandwiching these chromaticity ranges. This means that the chromaticity of light emission of the light emitting device 60 by the light emission of the light emitting part 62 and the lamp 63 can be kept within these chromaticity ranges by adjusting the content of the phosphor 15 in the light emitting part 62 and the like. Show.

(Effect of embodiment)
By selecting phosphors that satisfy the conditions described in the first embodiment and manufacturing a light emitting device using the selected phosphors, a light emitting device with a high luminous flux can be obtained. Moreover, according to the form of the light-emitting device according to the second to sixth embodiments, the light extraction efficiency of the light-emitting device is reduced due to the light emitted from the selected phosphor being absorbed by the phosphor having a long emission wavelength. Can be suppressed.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the invention.

  Moreover, said embodiment does not limit the invention which concerns on a claim. In addition, it should be noted that not all the combinations of features described in the embodiments are essential to the means for solving the problems of the invention.

10, 20a, 20b, 20c, 30, 40a, 40b, 50, 60 Light emitting device 12, 22, 31 Base 13 LED chip 14, 14a, 14b, 32 Sealing material 15, 25 Phosphor 42 Plate 63 Lamp 201, 202 , 301, 302 Light emitting part

Claims (5)

Measuring the emission spectrum of the phosphor;
A step of selecting, from the phosphors, those having an emission center-of-gravity wavelength λ _C represented by the following formula (1) of the emission spectrum of 530 nm or more and 570 nm or less and a half width of 90 nm or less;
A method for selecting phosphors.

However, in the above formula (1), λ represents a wavelength, and P (λ) represents the emission intensity of the phosphor expressed as a function of the wavelength. An LED chip mounted on a substrate;
A sealing material installed on the LED chip;
The phosphor selected by the phosphor selection method according to claim 1, which is included in the sealing material,
A light emitting device. A first fluorescent part having the LED chip, the sealing material, and the phosphor;
More than the second LED chip mounted on the second substrate, the second sealing material installed on the second LED chip, and the phosphor contained in the second sealing material A second fluorescent part having a second phosphor having a long emission wavelength;
Have
The light emitting device according to claim 2, wherein the first light emitting unit and the second light emitting unit are arranged side by side in a horizontal direction. A second sealing material installed under the sealing material;
A second phosphor having a longer emission wavelength than the phosphor, contained in the second sealing material;
The light emitting device according to claim 2, further comprising: A fluorescent portion having the LED chip, the sealing material, and the phosphor;
A lamp having an emission wavelength longer than that of the phosphor;
The light emitting device according to claim 2, comprising:

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