JP2021132176A - Light-emitting device - Google Patents

Abstract

To provide a light-emitting device that suppresses the emission of light having a wavelength of 650 nm or less, emits light having a wavelength exceeding 650 nm, and reduces glare.SOLUTION: A light-emitting device includes a light emitting element 11 that emits visible light and/or ultraviolet light, a fluorescent member 50 including a phosphor 70 that is excited by light emitted from a light emitting element and emits light having an emission peak wavelength in a range exceeding 650 nm, and a first film 80 is arranged on the light emitting side of the fluorescent member on an optical path of light emitted from the light emitting element, absorbs light having a wavelength of 650 nm or less, and transmits light having a wavelength exceeding 650 nm, and the thickness of a portion of the first film facing the light emitting element is larger than the thickness of the portion not facing the light emitting element.SELECTED DRAWING: Figure 1

Description

The present invention relates to a light emitting device.

A light emitting device that emits infrared light has been developed by combining a light emitting diode (Light Emitting Diode, hereinafter also referred to as "LED") and a phosphor that emits infrared light. Light emitting devices that emit infrared light are used, for example, in the field of sensors.

For example, in Patent Document 1, an LED that emits ultraviolet light and / or visible light is arranged on the bottom surface of a recess of a substrate, a phosphor that is excited by the LED and emits infrared light, and is arranged on an optical path from the LED. Disclosed is a light emitting device including a filter that covers an opening of a recess that does not transmit light emitted from an LED and visible light and that transmits infrared light. In Patent Document 1, the phosphor may be mixed with a binder resin such as a silicone resin, filled in the recess together with the resin and cured, or formed in a thin film on the inner surface of the filter, and the recess may be hollow. Is disclosed.

Japanese Unexamined Patent Publication No. 2011-23586

Since the filter that suppresses light emission from the LED and transmission of visible light and transmits infrared light has a constant thickness, the transmission of visible light is not suppressed on the optical path directly above the LED, and the transmission of visible light is not suppressed. Light emission and visible light may be transmitted and a glare may be felt. Further, if a cavity is formed in the recess of the substrate, heat dissipation from the LED may decrease.
One aspect of the present invention is to provide a light emitting device that suppresses the emission of light having a wavelength of 650 nm or less and emits light having a wavelength exceeding 650 nm to reduce glare.

The first aspect of the present invention is a light emitting element that emits visible light and / or ultraviolet light, and a phosphor that is excited by the light emitted from the light emitting element and emits light having an emission peak wavelength in a range exceeding 650 nm. On the optical path of the light emitted from the light emitting element and the fluorescent member, the fluorescent member is arranged on the light emitting side of the fluorescent member, absorbs light having a wavelength of 650 nm or less, and transmits light having a wavelength exceeding 650 nm. The first film is a light emitting device in which the thickness of the portion facing the light emitting element is larger than the thickness of the portion not facing the light emitting element.

A second aspect of the present invention includes a step of preparing a base having a first recess having an inner bottom surface and an inner side surface, a step of arranging a light emitting element on the inner bottom surface of the base, and a first step of the base. A first resin composition containing a phosphor which is excited by light emitted from the light emitting element and emits light having an emission peak wavelength in a range exceeding 650 nm and a first resin is filled in one recess and cured. The step of forming the fluorescent member covering the light emitting element, the step of modifying the surface of the fluorescent member, and the step of contacting the fluorescent member whose surface has been modified to bring the second resin and 650 nm. A method for manufacturing a light emitting device, which comprises a step of arranging a second resin composition containing the following light absorbing agent that absorbs light, curing the second resin composition, and arranging a first film. ..

According to one aspect of the present invention, it is possible to provide a light emitting device that suppresses the emission of light having a wavelength of 650 nm or less and emits light having a wavelength exceeding 650 nm to reduce glare.

It is a schematic cross-sectional view which shows an example of a light emitting device. It is a schematic cross-sectional view which shows an example of a light emitting device. It is a schematic cross-sectional view which shows an example of a light emitting device. It is a flowchart which shows an example of the manufacturing method of a light emitting device. The emission spectrum of the light emitting device according to the first embodiment is shown. It is a partially enlarged view of the emission spectrum of the light emitting device which concerns on Example 1, and shows the emission spectrum of the light emitting device which concerns on Example 1 in the wavelength range from around 400 nm to 650 nm or less. The emission spectrum of the light emitting device according to the second embodiment is shown. It is a partially enlarged view of the emission spectrum of the light emitting device which concerns on Example 2, and shows the emission spectrum of the light emitting device which concerns on Example 1 in the wavelength range from around 400 nm to 650 nm or less. The emission spectrum of the light emitting device according to the third embodiment is shown. It is a partially enlarged view of the emission spectrum of the light emitting device which concerns on Example 3, and shows the emission spectrum of the light emitting device which concerns on Example 1 in the wavelength range from around 400 nm to 650 nm or less.

Hereinafter, the light emitting device according to the present invention will be described based on one embodiment. However, the embodiments shown below are examples for embodying the technical idea of the present invention, and the present invention is not limited to the following light emitting devices. The relationship between the color name and the chromaticity coordinate, the relationship between the wavelength range of light and the color name of monochromatic light, and the like are in accordance with JIS Z8110.

An example of the light emitting device according to the embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a schematic cross-sectional view showing a light emitting device 100 according to the first embodiment of the present invention.

The light emitting device 100 is a fluorescent member including a light emitting element 11 that emits visible light and / or ultraviolet light, and a phosphor 70 that is excited by light emitted from the light emitting element 11 and emits light having an emission peak wavelength in a range exceeding 650 nm. A first unit that is arranged on the light path of the light emitted from the 50 and the light emitting element 11 and is arranged on the light emitting side of the fluorescent member 50, absorbs light having a wavelength of 650 nm or less, and transmits light having a wavelength exceeding 650 nm. The first film 80 includes a film 80, and the thickness T ¹ ep of the portion facing the light emitting element 11 is larger than ^{the thickness T 1 p of the portion not facing the light emitting element 11. In the first film 80, the thickness T 1} ep of the portion facing the light emitting element 11 on the optical path of the light emitted from the light ^{emitting element 11 is larger than the thickness T 1} p of the portion not facing the light emitting element 11. Since it is large, it is possible to suppress the emission of visible light and / or ultraviolet light emitted from the light emitting element 11 to the outside of the light emitting device, and reduce glare. The light emitting device 100 can confirm the operation of the light emitting device 100 in a state where the glare of the light emitted from the light emitting device 100 is reduced. Light having an emission peak wavelength in the range exceeding 650 nm is mainly emitted from the light emitting device 100, and emission of light having an emission peak wavelength in the range of 650 nm or less is suppressed, so that malfunction of other devices occurs. It is possible to exert the functions that can be used for an infrared sensor or the like without causing the light. Here, in the first film 80, the "portion facing the light emitting element 11" is a light emitting device having a first base 41 having a first recess 41r, with the open side of the first recess 41r as a flat surface. The light emitting device 100 is viewed from a direction perpendicular to the plane, and points directly above the light emitting element. On the other hand, in the first film 80, the "portion not facing the light emitting element 11" is a portion other than the portion facing the light emitting element 11, and mainly refers to the outer peripheral portion of the first recess 41r.

The light emitting device 100 includes a first base 41. The first base 41 includes a substrate 42 that constitutes the inner bottom surface of the first recess 41r of the first base 41, and a resin molding portion 43 that is integrated with the substrate 42 and forms the inner surface of the first recess 41r. The substrate 42 has a flat plate shape, and may be provided with a pair of electrodes on the surface forming the inner bottom surface of the first recess 41r, or may be provided with conductor wiring on the surface and / or inside of the substrate 42.

In the case of the light emitting device 100, in the light emitting element 11, the surface 11b on which a pair of positive and negative electrodes is formed is mounted on the conductor wiring of the substrate 42 of the first base 41 via a joining member such as a bump, for example, by flip-chip mounting ( It may be face-down mounted). When the light emitting element 11 is flip-chip mounted on the substrate 42, the surface 11a facing the surface 11b on which the pair of electrodes of the light emitting element 11 is formed is mainly a light extraction surface.

The light emitting element 11 is flip-chip mounted on the substrate 42 constituting the inner bottom surface of the first recess 41r of the first base 41, and the fluorescent member 50 is arranged on the inner bottom surface of the first recess 41r of the first base 41. It is arranged so as to cover the light emitting element 11. The fluorescent member 50 includes a second recess 50r that is recessed in the direction of the inner bottom surface of the first base 41. The second recess 50r of the fluorescent member 50 may be formed by causing a recess in the inner bottom surface direction of the first base 41 due to shrinkage of the resin composition constituting the fluorescent member 50 during curing. The shrinkage of the resin composition during curing may be referred to as "sink" of the resin.

The first film 80 is preferably arranged in contact with the second recess 50r of the fluorescent member 50. This is because the first film 80 can dissipate heat via the fluorescent member 50 or the like. The second resin composition constituting the first film 80 so as to come into contact with the second recess 50r of the fluorescent member 50 may be arranged in the second recess 50r by, for example, dropping. The second resin composition is arranged so as to slightly rise from the edge of the second recess 50r due to surface tension. By curing this second resin composition, the thickness T ^{1 ep of the portion of the first film 80 facing the light emitting element 11 is larger than the thickness T 1} p of the portion not facing the light emitting element 11. It can be formed to be large.

The light emitting device 100 may include a reflecting member 60 arranged so as to come into contact with a part of the light emitting element 11 and a part of the fluorescent member 50. It is preferable that the reflecting member 60 is in contact with a part of the light emitting element 11 and a part of the fluorescent member 50 and is arranged from the inner bottom surface to the inner side surface of the first recess 41r of the first base 41. The light emitted from the light emitting element 11 is efficiently reflected by the reflecting member 60 and incident on the fluorescent member 50, and the light emitted from the light emitting element 11 is efficiently wavelength-converted by the phosphor 70 in the fluorescent member 50. NS. The light whose wavelength is converted in the fluorescent member 50 is efficiently reflected by the reflecting member 60 and emitted to the outside of the light emitting device 100. By including the reflecting member 60, the light emitting device 100 can increase the radiant flux of light in the wavelength range exceeding 650 nm.

FIG. 2 is a schematic cross-sectional view showing another example of the light emitting device according to the first embodiment of the present invention. The light emitting device 101 has a second film 90 on the light emitting side of the first film 80. You may have it. The second film 90 is preferably arranged so as to be in contact with at least a part of the first film 80. The light emitting device 101 can improve the intensity of the light emitting device 101 by providing the first film 80 and the second film 90 on the light emitting side of the fluorescent member 50.

The entire surface of the first film 80 on the light emitting side may be covered with the second film 90. By covering the entire surface of the first film 80 on the light emitting side with the second film 90, the invasion of oxygen and water existing outside the light emitting device 101 into the light emitting device 101 is suppressed, and the first film 80 and the first film 80 and Deterioration of the phosphor 70 in the fluorescent member 50 can be suppressed. The second film may be one that transmits light, or may be one that reflects light in a specific wavelength range and transmits light in a specific wavelength range. The second film may be a dielectric multilayer film having a configuration of a distributed Bragg reflector (also referred to as “DBR”). The light emitting device 101 may have the same configuration as the light emitting device 100 except that the second film 90 is provided.

Light-emitting element As the light-emitting element, it is preferable to use a semiconductor light-emitting element, and it is more preferable to use a GaN-based semiconductor light-emitting element. As the light emitting element, the light emitting device provided with the GaN-based semiconductor light emitting element has high efficiency and high linearity with respect to the input, and can improve the strength against mechanical impact. For example, as the light emitting device, _{a GaN-based semiconductor light emitting device using a nitride-based semiconductor (In x} Al _Y Ga _1-XY N, 0 ≦ X, 0 ≦ Y, X + Y ≦ 1) can be used. The emission peak wavelength of the light emitting element is preferably in the range of 380 nm or more and 480 nm or less, and more preferably in the range of 400 nm or more and 460 nm or less.

The size of the light emitting element varies depending on the size of the target light emitting device. The thickness Te of the light emitting element may be, for example, in the range of 20 μm or more and 300 μm or less, in the range of 50 μm or more and 250 μm or less, or in the range of 100 μm or more and 200 μm or less.

1st base The substrate forming the inner bottom surface of the 1st base is preferably formed by using an insulating material. Examples of the insulating material constituting the substrate include ceramics such as alumina, aluminum nitride and mullite, phenol resin, epoxy resin, polyimide resin, bismaleimide triazine resin (BT resin), polyamide resin, polyphthalamide resin and liquid crystal polymer. Resin is mentioned. When the substrate is made of resin, it can be formed by dropping the resin or flowing it into the cavity and curing it. The substrate may be provided with conductor wiring on the surface and / or inside. Further, the substrate may be provided with a heat radiating member or a heat radiating terminal. The conductor wiring provided on the substrate and the terminals for heat dissipation can be formed by using metals such as Cu, Ag, Au, Al, Pt, Ti, W, Pd, Fe, and Ni and alloys thereof. The conductor wiring or the terminal for heat dissipation can be formed by, for example, an electrolytic plating, an electroless plating, a vapor deposition, or a sputtering method. The resin molding portion forming the inner surface of the first recess of the first base is selected from, for example, a phenol resin, an epoxy resin, a polyimide resin, a bismaleimide triazine resin, a polyamide resin, a polyphthalamide resin, and a liquid crystal polymer. It can be formed by using a fourth resin composition containing a resin.

Fluorescent member The fluorescent member can be formed by dropping a first resin composition containing a phosphor and a first resin into a first recess of a first base and curing the first resin composition. The fluorescent member may include a second recess that is recessed in the direction of the inner bottom surface of the first base due to shrinkage of the first resin composition during curing.

The first resin fluorescent member contains the first resin. The first resin is preferably at least one selected from the group consisting of silicone resin, modified silicone resin, epoxy resin and modified epoxy resin. The first resin contained in the fluorescent member is more preferably a silicone resin or a modified silicone resin having excellent heat resistance and weather resistance. Examples of the silicone resin include dimethyl silicone resin, phenyl-methyl silicone resin, and diphenyl silicone resin. As the first resin contained in the fluorescent member, one type of resin may be used alone, or two or more types may be used in combination.

Fluorescent member The fluorescent member includes a fluorescent substance. The phosphor contained in the fluorescent member is preferably excited by visible light and / or ultraviolet light emitted from the light emitting element, and emits light having an emission peak wavelength in a range exceeding 650 nm. For example, it is preferable that the light is excited by the light emission of a light emitting element having an emission peak wavelength in the range of 380 nm or more and 480 nm or less, and emits light having an emission peak wavelength in the range of more than 650 nm. The phosphor is excited by the emission of a light emitting element having an emission peak wavelength in the range of 380 nm or more and 480 nm or less, and preferably emits light having an emission peak wavelength in the range of more than 650 nm and 1800 nm or less. More preferably emits light in the range of 660 nm or more and 1700 nm or less, more preferably emits light having an emission peak wavelength in the range of 670 nm or more and 1600 nm or less, and emits light having an emission peak wavelength in the range of 680 nm or more and 1600 nm or less. Is particularly preferable.

The phosphors are a phosphor having a composition of a rare earth aluminate containing Ce and Nd, a phosphor having a composition of aluminum oxide containing Cr, a phosphor having a composition of aluminum oxide containing Cr and Ga, and a phosphor having a composition of Ce and Er. It is preferable to contain at least one selected from the group consisting of phosphors having a composition of a rare earth aluminate containing. By including the phosphor in the fluorescent member, the light emitted from the light emitting element can be wavelength-converted by the phosphor, and the target light having a wavelength exceeding 650 nm can be emitted from the light emitting device.

The phosphor having a composition of a rare earth aluminate containing Ce and Nd is selected from at least one rare earth element Ln ¹ selected from the group consisting of Y, Gd, Sc, Lu and La, and Al and Ga. A phosphor having a composition containing at least one element, Ce, and Nd is preferable. A phosphor having a composition of rare earth aluminate containing Ce and Nd _{may be expressed as, for example, Y 3} Al ₅ O ₁₂ : Ce, Nd, and may be expressed as YAG: Ce, Nd. Further, a phosphor having a composition of a rare earth aluminate containing Ce and Nd ^{may be expressed as Ln 1} ₃ Al ₅ O ₁₂ : Ce, Nd, or may be expressed as Ln ¹ AG: Ce, Nd. In the present specification, in the formula expressing the composition of the phosphor, the element before the colon (:) represents the element constituting the parent crystal and its molar ratio, and after the colon (:) represents the activating element. In the present specification, the "molar ratio" represents the molar amount of each element constituting the chemical composition in 1 mol of the chemical composition of the phosphor.

The phosphor having a composition of rare earth aluminate containing Ce and Nd may be a phosphor having a composition represented by the following formula (I).
^{_{(Ln 1 1-x-y}} Ce x Nd y) 3 (Al 1-z Ga z) 5 O 12 (I)
In formula (I), Ln ¹ is at least one rare earth element selected from the group consisting of Y, Gd, Sc, Lu and La, and x, y and z are 0.003 ≦ x ≦ 0.015. , 0.002 ≦ y ≦ 0.06, 0 ≦ z ≦ 0.8.

As a phosphor having a composition of a rare earth aluminate containing Ce and Nd, the contents disclosed in JP-A-2017-214442 can be incorporated herein by reference.

A phosphor having a composition of aluminum oxide containing Cr may be expressed as _{Al 2} O _{3: Cr.} The phosphor having a composition of aluminum oxide containing Cr may be a phosphor having a composition represented by the following formula (II).
(Al _1-w Cr _w ) ₂ O ₃ (II)
In formula (II), w is a number satisfying 0 <w <1. In formula (II), w may be a number satisfying 0.001 ≦ w ≦ 0.999.

A phosphor having a composition of aluminum oxide containing Cr and Gd may be represented as _{GdAlO 3: Cr.} The phosphor having a composition of aluminum oxide containing Cr and Gd may be a phosphor having a composition represented by the following formula (III).
(Gd _t Al _1-t-v Cr _v ) ₂ O ₃ (III)
In formula (III), t and v are numbers satisfying 0 <t <1, 0 <v <1, 0 <t + v <1, respectively. In formula (III), t may be a number satisfying 0.001 ≦ t ≦ 0.998, and v may be a number satisfying 0.001 ≦ v ≦ 0.998.

The phosphor having a composition of a rare earth aluminate containing Ce and Er is selected from at least one rare earth element Ln ² selected from the group consisting of Y, Gd, Sc, Lu and La, and Al and Ga. A phosphor having a composition containing at least one element, Ce, and Er is preferable. Examples of a phosphor having a composition of rare earth aluminate containing Ce and _{Er, Y 3 Al 5 O 12} : Ce, may represent a Er, YAG: Ce, sometimes expressed as Er. Further, a phosphor having a composition of a rare earth aluminate containing Ce and Er ^{may be expressed as Ln 2} ₃ Al ₅ O ₁₂ : Ce, Er, and may be expressed as Ln ² AG: Ce, Er.

The phosphor having a composition of a rare earth aluminate containing Ce and Er may be a phosphor having a composition represented by the following formula (IV).
^{_{(Ln 2 1-q-r}} Ce q Er r) 3 (Al 1-s Ga s) 5 O 12 (IV)
In formula (IV), Ln ² is at least one rare earth element selected from the group consisting of Y, Gd, Sc, Lu and La, and q, r and s are 0.003 ≦ q ≦ 0.015. , 0.002 ≦ r ≦ 0.06, 0 ≦ s ≦ 0.8.

The phosphor is preferably particles. When the phosphor is a particle, the average particle size of the phosphor particles is preferably in the range of 3 μm or more and 60 μm or less, more preferably in the range of 5 μm or more and 50 μm or less, and in the range of 10 μm or more and 30 μm or less. It is more preferable to be inside. When the average particle size of the phosphor particles is within the range of 3 μm or more and 60 μm or less, the dispersibility of the phosphor particles in the first resin composition constituting the fluorescent member is good, and the handleability when forming the fluorescent member is good. good. The average particle size of the phosphor particles can be measured by the Fisher Sub-Sieve Sizar method (also referred to as “FSSS method”). The FSSS method is a kind of air permeation method, and is a method of measuring the specific surface area by utilizing the flow resistance of air and mainly determining the particle size of primary particles. The average particle size measured by the FSSS method is the Fisher Sub-Sieve Sizar's Number. When the phosphor is a particle and the average particle size measured by the FSSS method is within the range of 10 μm or more and 30 μm or less, the light from the light emitting element is efficiently wavelength-converted and has an emission peak wavelength in the range exceeding 650 nm. The emission intensity of light can be increased.

The phosphor in the fluorescent member is arranged so as to cover the light extraction surface of the light emitting element. It is preferable that the thickness of the fluorescent member has a portion having a thickness larger than the thickness Te of the light emitting element. The fluorescent member may be provided with a second recess that is recessed in the direction of the inner bottom surface of the base due to shrinkage of the first resin composition constituting the fluorescent member during curing, and the fluorescent member has a different thickness for each part. May be good. For example, in a light emitting device, the thickness of a portion of the fluorescent member facing the light emitting element may be smaller, larger, or the same as the thickness of the portion not facing the light emitting element. good. Here, the "portion facing the light emitting element" of the fluorescent member refers to directly above the light emitting element when viewed from a direction perpendicular to the plane of the substrate on the side on which the light emitting element is arranged. The “portion not facing the light emitting element” of the fluorescent member is a portion other than the portion facing the light emitting element, and mainly refers to the outer peripheral portion of the first recess.

First film The first film preferably contains a second resin and a light absorber that absorbs light of 650 nm or less. The second resin includes at least one selected from the group consisting of a silicone resin and a modified silicone resin. The light absorber may be a dye that absorbs light having a wavelength of 650 nm or less and transmits light having a wavelength exceeding 650 nm, and the light absorber may be a pigment or an inorganic material in addition to the dye. The first film is cured by arranging a second resin composition containing a second resin or a precursor of the second resin and a light absorber that absorbs light of 650 nm or less in the second recess of the fluorescent member. Can be formed. For the second resin composition constituting the first film, the contents disclosed in JP-A-2019-131806 can be referred to.

The thickness of the first film varies depending on the size of the light emitting device. ^{If the thickness T 1} ep of the portion facing the light emitting element of ^{the first film is formed larger than the thickness T 1} p of the portion not facing the light emitting element of the first film, it is emitted from the light emitting element. It is possible to suppress the emission of visible light and / or ultraviolet light to the outside of the light emitting device, and reduce the glare of the light emitted from the light emitting device. For example, in a light emitting device as shown in FIGS. 1, 2 and 3 described later, when the thickness of the light emitting element is within the range of 120 μm or more and 180 μm or less, the portion of the first film facing the light emitting element The maximum thickness T ¹ ep may be, for example, in the range of 200 μm or more and 550 μm or less, or may be in the range of 250 μm or more and 500 μm or less. When the thickness of the light emitting element is within the range of 120 μm or more and 180 μm or less, the minimum thickness T ¹ p that can be measured in the portion of the first film that does not face the light emitting element is, for example, within the range of 20 μm or more and 150 μm or less. It may be in the range of 30 μm or more and 100 μm or less. For example, when the thickness of the light emitting element is 150 μm, the maximum thickness T ¹ ep among the portions facing the light emitting element of the first film may be 450 μm, facing the light emitting element of the first film. ^{The minimum thickness T 1} p that can be measured in the non-existent portion may be 75 μm.

Second film The second film arranged on the light emitting side of the first film is, for example, at least one third resin selected from the group consisting of epoxy resin, modified epoxy resin, silicone resin, or modified silicone resin, or It can be formed from a glass material. Examples of the glass material constituting the second film include borosilicate glass, quartz glass, sapphire glass, calcium fluoride glass, aluminoborosilicate glass, oxynitride glass, chalcogenide glass and the like. When the second film is made of a glass material, oxygen can further suppress the invasion of water into the light emitting device, and the light having an emission peak wavelength in the range exceeding 650 nm emitted from the fluorescent member can be used. The intensity of the light emitting device can be improved without hindering the emission. The second film and the first film may be bonded with an adhesive. As the adhesive, an adhesive containing an epoxy resin, a silicone resin, or the like may be used, or an organic adhesive having a high refractive index, an inorganic adhesive, a low melting point glass, or the like may be used. The second film may contain a filler or the like, or may contain a diffusing agent or the like, in order to improve the thermal conductivity.

Since the second film is formed on the surface of the first film, the thickness of the portion of the second film facing the light emitting element and the thickness of the portion of the second film not facing the light emitting element may be different. , The thickness may be the same. The maximum thickness of the second film may be a thickness that can suppress the intrusion of oxygen and water into the light emitting device. For example, when the thickness Te of the light emitting element is within the range of 120 μm or more and 180 μm or less, when the second film is provided for the purpose of suppressing the invasion of oxygen or water into the light emitting device, the second film is the largest. The thickness can be, for example, 30 μm or more and 300 μm or less, 40 μm or more and 280 μm or less, or 50 μm or more and 270 μm or less. In the second film, the "portion facing the light emitting element" is a light emitting device having a first base having a first recess, with the open side of the first recess as a plane, and a direction perpendicular to the plane. Looking at the light emitting device from, it points directly above the light emitting element. On the other hand, in the second film, the "portion not facing the light emitting element" is a portion other than the portion facing the light emitting element, and mainly refers to the outer peripheral portion of the first recess 41r.

The second film may be arranged to protect the first film from moisture or the like, and dissipates heat from the first film that absorbs visible light and converts the absorbed light into heat to the outside through the second film. It may be arranged for ease of use. When the second film is arranged to facilitate heat dissipation to the outside, it is preferable that the second film is coated so as to be in contact with the surface of the first film and the upper surface of the base. The second film may be, for example, a film that reflects light in the wavelength range emitted from the light emitting element and transmits the light wavelength-converted by the phosphor in the fluorescent member. For example, when the second film is a DBR film, as the second film, a plurality of sets of a set of dielectric layers composed of a low refractive index layer and a high refractive index layer are formed on a base layer made of an arbitrary oxide film or the like, for example. Those having a multilayer structure in which 2 to 5 sets of a low refractive index layer and a high refractive index layer are laminated can be used. When the DBR film is a dielectric multilayer film, for example _{, a layer containing SiO 2 can be used as the low refractive index layer, and Nb 2} O ₅ , TiO ₂ , ZrO ₂ or Ta ₂ O ₅ is contained as the high refractive index layer. Layers can be used. When the second film is a DBR film, the total film thickness of the DBR film may be in the range of 0.2 μm or more and 1 μm or less.

Reflective member The reflective member preferably contains a fifth resin or glass and a reflective material. Examples of the reflective material include oxides containing at least one selected from the group consisting of yttrium, zirconium, aluminum, and titanium whose reflectance at a specific wavelength is equal to or higher than a specific value. For example, an oxide containing at least one selected from the group consisting of yttrium, zirconium, aluminum and titanium having a reflectance of 50% or more of light from a light emitting element having an emission peak wavelength in the range of 400 nm or more and 480 nm or less. Can be mentioned. The reflective member may contain a white pigment whose reflectance at a specific wavelength is not greater than or equal to a specific value. White pigments include titanium oxide, zinc oxide, magnesium oxide, magnesium carbonate, magnesium hydroxide, calcium carbonate, calcium hydroxide, calcium silicate, magnesium silicate, barium titanate, barium sulfate, aluminum hydroxide, aluminum oxide, zirconium oxide. One of them can be used alone, or two or more of them can be used in combination. The shape of the white pigment is not particularly limited and may be amorphous or crushed, but a spherical shape is preferable from the viewpoint of fluidity. The particle size of the white pigment is, for example, about 0.1 μm or more and 0.5 μm or less. For the particle size of the white pigment, for example, the catalog value can be referred to. Examples of the fifth resin include at least one resin selected from the group consisting of thermoplastic resins and thermosetting resins. Examples of the glass material include borosilicate glass, quartz glass, sapphire glass, calcium fluoride glass, aluminoborosilicate glass, oxynitride glass, chalcogenide glass and the like. The fifth resin or glass material contained in the reflective member may be the same type of resin or glass material as the third resin or glass material contained in the second film, or may be a different resin or glass material.

FIG. 3 is a schematic cross-sectional view showing another example of the light emitting device according to the first embodiment of the light emitting device. The light emitting device 102 includes a second base 44 having a different shape from the first base 41 of the light emitting device 101, and a surface 12b facing the surface 12a on which a pair of electrodes of the light emitting element 12 are formed. A pair of positive and negative electrodes of the light emitting element 12 are arranged on the first lead 21 forming the inner bottom surface of the second base 44, and face up via the first lead 21, the second lead 22, and the wire 30, respectively. The points to be implemented are different, and other points are common.

The light emitting device 102 includes a light emitting element 12 that emits visible light and / or ultraviolet light, and a fluorescent member 50 including a phosphor 70 that is excited by light emission of the light emitting element 12 and emits light having a light emitting peak wavelength in a range exceeding 650 nm. The first film 80, which is arranged on the light path of the light emitted from the light emitting element 12 and is arranged on the light emitting side of the fluorescent member 50, absorbs the light having a wavelength of 650 nm or less, and transmits the light having a wavelength exceeding 650 nm. In the first film 80, the thickness T ¹ ep of the portion facing the light emitting element 12 is larger than ^{the thickness T 1 p of the portion not facing the light emitting element 12.} The light emitting device 102 absorbs light having a wavelength of 650 nm or less, and the first film 80 that transmits light having a wavelength exceeding 650 nm has a thickness T ¹ ep of a portion facing the light emitting element 12 on the light emitting element 12. Since the thickness of the non-opposing portion ^{is larger than T 1} p, it is possible to suppress the emission of visible light and / or ultraviolet light emitted from the light emitting element 12 to the outside of the light emitting device and suppress glare. .. Here, in the first film 80 of the light emitting device 102, the "portion facing the light emitting element 12" is an opening of the light emitting device having the first base 44 having the first recess 44r in the first recess 44r. The side is a flat surface, and the light emitting device 102 is viewed from a direction perpendicular to the flat surface, and points directly above the light emitting element 12. On the other hand, in the first film 80, the "portion not facing the light emitting element 12" is a portion other than the portion facing the light emitting element 12, and mainly refers to the outer peripheral portion in the first recess 44r.

The second base light emitting device 102 includes a second base 44. The second base 44 includes a first lead 21, a second lead 22, and at least one fourth resin selected from the group consisting of a thermoplastic resin and a thermosetting resin, and the second base 44 contains a second base 44. The resin molding portion 45 forming the inner surface of the first recess 44r is integrally molded. The first lead 21 and the second lead 22 of the second base 44 form an inner bottom surface of the second base 44. The second base 44 has a first recess 44r having an inner bottom surface formed of the first lead 21 and the second lead 22 and an inner side surface formed of the resin molding portion 45. A light emitting element 12 is placed on the inner bottom surface of the first recess 44r. The light emitting element 12 has a pair of positive and negative electrodes, and the pair of positive and negative electrodes are electrically connected to the first lead 21 and the second lead 22, respectively, via a wire 30. The light emitting device 102 can emit light by receiving power supply from the outside via the first lead 21 and the second lead 22.

The fluorescent member 50 including the phosphor 70 is arranged so as to cover the light emitting element 12 arranged in the first lead 21 forming the inner bottom surface of the first recess 44r of the second base 44. The fluorescent member 50 includes a second recess 50r that is recessed in the direction of the inner bottom surface of the second base 44. The second recess 50r of the fluorescent member 50 may be formed by causing a recess in the inner bottom surface direction of the second base 44 due to shrinkage of the resin composition constituting the fluorescent member 50 during curing.

The first film 80 is preferably arranged in contact with the second recess 50r of the fluorescent member 50. When the second resin composition constituting the first film 80 so as to come into contact with the second recess 50r of the fluorescent member 50 is arranged in the second recess 50r by, for example, dropping, the surface tension of the second resin composition causes. The second resin composition is arranged so as to be slightly raised from the edge of the second recess 50r. By curing this second resin composition, the thickness T ¹ ep of the portion of the first film 80 facing the light emitting element 12 becomes larger than ^{the thickness T 1} p of the portion not facing the light emitting element 12. Can be formed as follows.

The light emitting device 102 may include a second film 90 on the light emitting side of the first film 80. The light emitting device 102 may include a reflecting member 60 arranged so as to come into contact with a part of the light emitting element 12 and a part of the fluorescent member 50. As the second film 90 and the reflecting member 60, the same ones as the second film 90 and the reflecting member 60 used for the light emitting device 101 can be used.

The light emitting device has an emission intensity of the maximum emission peak wavelength Lv in the wavelength range of 650 nm or less with respect to the emission intensity Ir at the maximum emission peak wavelength Lr in the wavelength range exceeding 650 nm in the emission spectrum of the light emitting device. Those having a ratio Iv / Ir of 0.01 or less are preferable. When the light emitting device emits light having an emission intensity ratio Iv / Ir of 0.01 or less in the emission spectrum, the emission of light having an emission peak wavelength in the range of 650 nm or less to the outside is suppressed. And the glare can be reduced. The light emitting device may emit light having an emission intensity ratio Iv / Ir of 0.005 or less, or may emit light of 0.003 or less in the emission spectrum of the light emitting device. It may emit light of 002 or less. The light emitting device may emit light having a light emitting intensity ratio Iv / Ir of 0.0001 or more in the light emitting spectrum of the light emitting device.

Method of manufacturing a light emitting device The method of manufacturing a light emitting device includes a step of preparing a base having a first concave portion having an inner bottom surface and an inner side surface, a step of arranging a light emitting element on the inner bottom surface of the base, and a step of arranging a light emitting element of the base. The first recess is filled with a second resin composition containing a first resin and a phosphor that is excited by light emitted from a light emitting element and emits light having an emission peak wavelength in a range exceeding 650 nm, and is cured. A step of forming a fluorescent member covering the light emitting element, a step of modifying the surface of the fluorescent member, and a step of contacting the surface of the modified fluorescent member with the second resin and light having a wavelength of 650 nm or less. It includes a step of arranging a second resin composition containing a light absorber to be absorbed and curing the second resin composition to form a first film.

FIG. 4 is a flowchart showing an example of a method for manufacturing a light emitting device according to a second embodiment. The method for manufacturing the light emitting device includes a base preparation step S301, a light emitting element placement step S302, a fluorescent member forming step S303, a modification treatment step S304, and a first film placement step S305. The method for manufacturing the light emitting device may include an arrangement step S306 for arranging the second film in a step after the arrangement step S305 for the first film. In the method for manufacturing a light emitting device, a step of forming a reflecting member may be included after the step of arranging the light emitting element S302 and before the step of forming the fluorescent member S303. In the method of manufacturing a light emitting device, when a collecting base in which a plurality of first recesses are formed is used, an individual piece for separating the collecting base for each light emitting device in each unit region having one first recess. It may include a chemical conversion step.

Base preparation step In the base preparation step, a base having a first recess having an inner bottom surface and an inner side surface is prepared. When preparing the first base 41 as shown in FIG. 1 or 2, a substrate 42 having conductor wiring on the surface and / or inside forming the inner bottom surface of the first recess 41r is prepared, and a resin molding die is prepared. The substrate 42 is placed at a predetermined position in the cavity of the mold, the fourth resin composition constituting the inner surface of the first recess 41r is injected into the cavity, and the substrate 42 and the resin molding portion 43 are integrally molded. The first base 41 provided with the first recess 41r is prepared.

When preparing the second base 44 as shown in FIG. 3, the first lead 21 and the second lead 22 are arranged at predetermined positions in the cavity of the resin molding mold, and the inside of the first recess 44r is placed in the cavity. The fourth resin composition constituting the side surface is injected, and the first lead 21, the second lead 22, and the resin molding portion 45 are integrally molded to form a second base 44 provided with the first recess 44r. prepare. The first lead 21 and the second lead 22 form the inner bottom surface of the first recess 44r of the second base 44, and the resin molding portion 45 constitutes the inner surface of the second base 44.

Light emitting element arrangement step In the light emitting element arrangement step, the light emitting element is arranged on the inner bottom surface of the base. When the light emitting device 100 or the light emitting device 101 is manufactured, the surface 11b on which a pair of positive and negative electrodes of the light emitting element 11 is formed is mounted on the conductor wiring of the substrate 42 via a joining member such as a bump, for example, by flip-chip mounting (face). Down mounted). When the light emitting element 11 is face-down mounted on the substrate 42, the surface 11a facing the surface 11b on which the pair of electrodes of the light emitting element 11 is formed is mainly a light extraction surface.

When manufacturing the light emitting device 102, a surface 12b facing the surface 12a on which a pair of positive and negative electrodes of the light emitting element 12 is formed is arranged on the first lead 21, and a pair of positive and negative electrodes are respectively provided via a wire 30. It is electrically connected to the first lead 21 and the second lead 22. When the light emitting element 12 is face-up mounted on the first lead 21 and the second lead 22 via the wire 30, the surface 12b on which the pair of electrodes of the light emitting element 12 is formed is mainly the light extraction surface. Become.

Reflective member forming step The method of manufacturing the light emitting device is a step of forming a reflective member around the light emitting element in the first recess of the base after the process of arranging the light emitting element and before the step of forming the fluorescent member. May include. The reflective member is formed by arranging a reflective material and a fifth composition containing a fifth resin or glass material so as to be in contact with a part of the inner bottom surface and a part of the inner side surface of the first recess and curing the reflective material. Can be done.

Fluorescent member forming step In the fluorescent member forming step, a phosphor that is excited by light emitted from a light emitting element and emits light having an emission peak wavelength in a range exceeding 650 nm in the first concave portion of the base, and a first The first resin composition containing the resin is filled and cured to form a fluorescent member that covers the light emitting element. The content of the phosphor in the first resin composition is preferably in the range of 20 parts by mass or more and 500 parts by mass or less, and more preferably 30 parts by mass or more and 450 parts by mass or less with respect to 100 parts by mass of the resin. It is within the range, and more preferably within the range of 40 parts by mass or more and 400 parts by mass or less. When the content of the phosphor in the first resin composition is within the range of 20 parts by mass or more and 350 parts by mass or less with respect to 100 parts by mass of the resin, the main light extraction surface and light emission of the light of the light emitting element. The light extraction surface on the side surface of the element is covered with a phosphor, the light emitted from the light emitting element is efficiently absorbed, and the wavelength is converted by the phosphor to emit light having an emission peak wavelength in a range exceeding 650 nm, which has a high emission flux. be able to.

When the phosphor has a composition of a rare earth aluminate containing Ce and Nd in order to emit light having an emission peak wavelength in a range exceeding 650 nm, which has a high emission flux, the first resin The content of the phosphor in the composition is preferably in the range of 20 parts by mass or more and 500 parts by mass or less, and more preferably in the range of 30 parts by mass or more and 450 parts by mass or less with respect to 100 parts by mass of the resin. Yes, more preferably 40 parts by mass or more and 400 parts by mass or less, and particularly preferably 50 parts by mass or more and 300 parts by mass or less.

In order to emit light having an emission peak wavelength in a range exceeding 650 nm, which has a high emission flux, from the light emitting device, when the phosphor is a phosphor having a composition of aluminum oxide containing Cr, it is contained in the first resin composition. The content of the phosphor is preferably in the range of 50 parts by mass or more and 300 parts by mass or less, more preferably in the range of 60 parts by mass or more and 250 parts by mass or less, and further preferably in the range of 50 parts by mass or more and 300 parts by mass or less with respect to 100 parts by mass of the resin. Is in the range of 70 parts by mass or more and 200 parts by mass or less, and particularly preferably in the range of 80 parts by mass or more and 150 parts by mass or less.

When the phosphor has a composition of aluminum oxide containing Cr and Ga in order to emit light having an emission peak wavelength in a range exceeding 650 nm, which has a high emission flux, the first resin composition The content of the phosphor in the resin is preferably in the range of 50 parts by mass or more and 500 parts by mass or less, and more preferably in the range of 70 parts by mass or more and 480 parts by mass or less with respect to 100 parts by mass of the resin. It is more preferably in the range of 80 parts by mass or more and 450 parts by mass or less, and particularly preferably in the range of 100 parts by mass or more and 400 parts by mass or less.

The fluorescent member may contain other components such as a filler, a light stabilizer, and a colorant in addition to the phosphor and the resin. Examples of the filler include silica, barium titanate, titanium oxide, aluminum oxide and the like.

When the first resin composition forms the light emitting device 100 shown in FIG. 1, the light emitting device 101 shown in FIG. 2, or the light emitting device 102 shown in FIG. 3, it is dropped using, for example, a dispenser, and the first base 41 is the first. The first resin composition is filled in the first recess 41r of the first recess 41r or the first recess 44r of the second base 44 and cured to form the fluorescent member 50.

The first resin composition is dropped and filled in the first recess 41r of the first base 41 or the first recess 44r of the second base 44, and then shrinks at the time of curing, and the first base 41 or the second A second recess 50r recessed in the direction of the inner bottom surface of the base 44 may be formed.

Modification treatment step In the modification treatment step, the surface of the fluorescent member is modified. By modifying the surface of the fluorescent member, the adhesion between the second resin composition constituting the first film and the fluorescent member is improved, and the unevenness of wet spread of the second resin composition is eliminated. As a result, the thickness T ¹ ep of the first film of the portion facing the light emitting element becomes thicker than ^{the thickness T 1} p of the first film of the portion not facing the light emitting element. You can mold things. When the fluorescent member includes the second recess, it is preferable to modify the surface of the fluorescent member including the inner surface of the second recess. Examples of the reforming treatment include plasma treatment, corona discharge treatment, ozone water treatment and the like. The reforming treatment is preferably a plasma treatment capable of performing the reforming treatment at a low temperature. As the plasma treatment, nitrogen plasma, hydrogen plasma, or halogen plasma can be performed by the plasma CVD method. The reforming treatment can be carried out in the atmosphere and may be carried out in an oxygen atmosphere. Further, the reforming treatment is preferably carried out in a temperature range of 25 ° C. or higher and 100 ° C. or lower, may be carried out in a temperature range of 40 ° C. or higher and 90 ° C. or lower, and is carried out in a temperature range of 50 ° C. or higher and 80 ° C. or lower. You may go.

First film placement step The first film placement step is a second resin composition comprising a second resin and a light absorber that absorbs light of 650 nm or less by contacting the surface with a modified fluorescent member. An object may be arranged and the second resin composition may be cured to arrange the first film. The second resin composition has improved adhesion to the surface-modified fluorescent member, and the surface tension of the second resin composition prevents the second resin composition from flowing out from the second recess of the fluorescent member. It is arranged so as to rise from the edge of the recess. By curing this second resin composition, a first film having ^{a thickness T 1} ep of a portion facing the light emitting element ^{larger than a thickness T 1 p of a portion not facing the light emitting element is arranged.} Can be done. In the step of forming the first film, when the fluorescent member has the second recess, for example, the second resin composition is dropped into the second recess using a dispenser to cure the second resin composition. It is preferable to arrange the first film. When the second resin composition is dropped and filled in the second recess of the fluorescent member, the surface tension of the second resin composition causes the second resin composition to swell from the edge of the second recess and face the light emitting element. It is relatively easy to arrange the first film in which the thickness T ^{1 ep of the portion is larger than the thickness T 1} p of the portion not facing the light emitting element.

Second film placement step In the second film placement step, the third composition may be placed on the light emitting side of the first film, cured, and the second film may be placed. The third composition may contain at least one third resin selected from the group consisting of epoxy resins, modified epoxy resins, silicone resins or modified silicone resins, or glass materials. The third composition can be dropped onto the light emitting side of the first film using a dispenser, and the third composition can be arranged and cured so as to cover the entire first film. The first film and the second film may be bonded with an adhesive, and the second film may be arranged after applying the adhesive to the light emitting side of the first film. When the second film is a DBR film, the second film may be bonded to the first film via an adhesive and arranged. When the second film is a DBR film, a low refractive index layer and a high refractive index layer are alternately alternated on the light emitting side of the first film by an atomic layer deposition method (ALD: Atomic Layer Deposition), sputtering, a vapor deposition method, or the like. It may be formed by forming a film on the surface.

When the first base or the second base is a collective base having a plurality of first recesses 41r or a plurality of first recesses 44r, a light emitting device of an individual unit region having one first recess 41r. Each may include an individualization step of separating the assembly base.

Hereinafter, the present invention will be specifically described with reference to Examples. The present invention is not limited to these examples.

Example 1
The light emitting device 100 shown in FIG. 1 was manufactured.

Preparation of the first base The first base 41 having the first recess 41r was prepared. The first base 41 includes a resin molding portion 43 in which a substrate 42 is used and a fourth resin composition containing a silicone resin is cured, the inner bottom surface is composed of the substrate 42, and the inner side surface is composed of the resin molding portion 43. It has a first recess 41r that has been made.

Arrangement of Light Emitting Elements A light emitting device 11 made of a GaN-based semiconductor having a light emitting peak wavelength of 450 nm and having a thickness of 150 μm was prepared. The light emitting element 11 was flip-chip mounted on the conductor wiring of the substrate 42 constituting the inner bottom surface of the first recess 41r of the first base 41, and the light emitting element 11 was arranged.

Formation of Reflective Member A fifth composition containing titanium oxide and a silicone resin as a reflective material is placed around the light emitting element 11 of the first recess 41r of the first base 41, and the fifth composition is cured. The reflective member 60 was formed.

Formation of Fluorescent Member A first resin composition containing 200 parts by mass of a phosphor having a composition of a rare earth aluminate containing Ce and Nd represented by YAG: Ce and Nd was prepared with respect to 100 parts by mass of a silicone resin. .. The first resin composition was dropped into the first recess 41r of the first base 41 using a dispenser and cured to form the fluorescent member 50. The fluorescent member 50 has a second recess 50r that is recessed in the direction of the inner bottom surface of the first base 41 due to shrinkage of the first resin composition during curing.

Modification treatment The surface of the fluorescent member 50 including the inner surface of the second recess 50r is plasma-treated by a plasma CVD method using an atmospheric pressure plasma discharge processing apparatus (product name: PC30B-HS, manufactured by Panasonic) to fluoresce. The surface of the member 50 was modified.

Arrangement of the first film A second resin composition containing a dye as a light absorber that absorbs light having a wavelength of 650 nm or less and transmits light having a wavelength exceeding 650 nm, and a silicone resin or a silicone resin precursor (product name: AIR-7051, manufactured by Shin-Etsu Chemical Industry Co., Ltd.) was prepared. The second resin composition is dropped into the second recess 50r of the fluorescent member 50 so that the thickness T ¹ ep of the portion facing the light emitting element becomes larger than ^{the thickness T 1} p of the portion not facing the light emitting element. The second resin composition is arranged so as to rise from the edge of the first recess 41r of the first base 41 or the edge of the second recess of the fluorescent member due to the surface tension of the second resin composition. The first film was arranged by curing this second resin composition. In the first film 80, the thickness T ¹ ep of the portion facing the light emitting element 11 is larger than ^{the thickness T 1 p of the portion not facing the light emitting element 11.}

Example 2
The light emitting device 100 shown in FIG. 1 was manufactured. As a first resin composition for forming a light emitting element 11 having a light emitting peak wavelength of 405 nm and a thickness of 150 μm and a fluorescent member 50, Al ₂ O ₃ : with respect to 100 parts by mass of a silicone resin: The light emitting device 100 was manufactured in the same manner as in Example 1 except that the first resin composition containing 150 parts by mass of a phosphor having a composition of aluminum oxide containing Cr represented by Cr was used. In the first film 80, the thickness T ¹ ep of the portion facing the light emitting element 11 is larger than ^{the thickness T 1 p of the portion not facing the light emitting element 11.}

Example 3
The light emitting device 100 shown in FIG. 1 was manufactured. As a first resin composition for forming a light emitting element 11 having a light emitting peak wavelength of 405 nm and a thickness of 150 μm and a fluorescent member 50, GaAlO ₃ : Cr is used with respect to 100 parts by mass of a silicone resin. A light emitting device 100 was manufactured in the same manner as in Example 1 except that the first resin composition containing 200 parts by mass of a phosphor having a composition of aluminum oxide containing Cr was used. In the first film 80, the thickness T ¹ ep of the portion facing the light emitting element 11 is larger than ^{the thickness T 1 p of the portion not facing the light emitting element 11.}

Evaluation of Light Emitting Device Measurement of Thickness of First Film The cross section of the light emitting device is cut from a direction perpendicular to the substrate of each light emitting device according to Examples 1 to 3 and the cross section of the light emitting device is scanned by a scanning electron microscope (SEM). The SEM photograph observed in the above was obtained. In the SEM photograph of the cross section of each light emitting device, the thickness of the light emitting element, the largest thickness T ¹ ep among the parts facing the light emitting element of the first film, and the part not facing the light emitting element of the first film. The smallest measurable thickness T ¹ p was measured.

Emission spectrum For each of the light emitting devices according to Examples 1 to 3, the light emission spectrum showing the light emission intensity with respect to the wavelength of each light emitting device was measured by using the total luminous flux measuring device. In the emission spectrum of each light emitting device, the emission peak wavelength in the range of 400 nm or more and less than 500 nm was measured as the emission peak wavelength Le of the light emitting element. Further, in the emission spectrum of each light emitting device, the maximum emission peak wavelength Lv in the range of 400 nm or more and 650 nm or less was measured. Further, in the emission spectrum of each light emitting device, the maximum emission peak wavelength Lr in the range exceeding 650 nm was measured. The emission intensity ratio Iv / Ir of the emission intensity Iv of the maximum emission peak wavelength Lv in the range of 400 nm or more and 650 nm or less was measured with respect to the emission intensity Ir of the maximum emission peak wavelength Lr in the range exceeding 650 nm. The results are shown in Table 1.

Saturation (x, y)
For each light emitting device according to Examples 1 to 3, the chromaticity x and y in the chromaticity coordinates of the CIE 1931 system were measured by an optical measurement system combining a multi-channel spectroscope and an integrating sphere.

Radiant flux (mW) and luminous efficiency (mW / W)
For each light emitting device according to Examples 1 to 3, the radiant flux was measured using a total luminous flux measuring device using an integrating sphere. Further, the ratio of the radiant flux (mW) in the wavelength range of 700 nm or more and 1100 nm or less to the electric power (W) supplied to the light emitting device was measured as the luminous efficiency (mW / W).

Table 1 shows the evaluation results of each light emitting device according to Examples 1 to 3.

In each of the light emitting devices according to the first to third embodiments, the thickness T ^{1 ep of the portion of the first film facing the light emitting element is larger than the thickness T 1} p of the portion not facing the light emitting element of the first film. big. Therefore, the light emitting device according to Examples 1 to 3 absorbs light having a wavelength of 650 nm or less by the first film, and the emission of visible light and / or ultraviolet light having a wavelength of 650 nm or less to the outside of the light emitting device is suppressed, resulting in glare. Can be reduced. Further, the radiant flux of each light emitting device according to Examples 1 to 3 exceeds 50.0 mW, and the luminous efficiency is 35 (mW / mW /), which is the ratio of the radiant flux (mW) in the wavelength range of 700 nm or more and 1100 nm or less to the supplied power. Light having a sufficient energy that exceeds W) and can be used as an infrared sensor or the like is emitted from each of the light emitting devices according to the first to third embodiments.

FIG. 5 shows the emission spectrum of the light emitting device according to the first embodiment. In the emission spectrum, the light emitting apparatus according to the first embodiment has an emission intensity Iv at the maximum emission peak wavelength Lv in the wavelength range of 400 nm or more and 650 nm or less with respect to the emission intensity Ir at the maximum emission peak wavelength Lr in the wavelength range exceeding 650 nm. The emission intensity ratio of Iv / Ir is 0.002 or less, and the emission of light having an emission peak wavelength of 650 nm or less is suppressed.

FIG. 6 is a partially enlarged view of the emission spectrum shown in FIG. 5, showing the emission spectrum in the wavelength range from around 400 nm to 650 nm or less of the light emitting device according to the first embodiment. In the light emitting device according to the first embodiment, a peak existing in the range of 400 nm or more and less than 500 nm could hardly be confirmed in the light emitting spectrum, and the light from the light emitting element was hardly emitted to the outside. Further, in the light emitting device according to the first embodiment, the emission intensity Iv at the maximum emission peak wavelength Lv in the wavelength range of 400 nm or more and 650 nm is also the emission intensity Ir at the maximum emission peak wavelength Lr in the wavelength range exceeding 650 nm. Therefore, even when light in the wavelength range of 650 nm or less is emitted, the operation of the light emitting device can be confirmed in a state where the glare of the light emitted from the light emitting device is reduced.

FIG. 7 shows the emission spectrum of the light emitting device according to the second embodiment. In the emission spectrum, the light emitting apparatus according to the second embodiment has an emission intensity Iv at the maximum emission peak wavelength Lv in the wavelength range of 400 nm or more and 650 nm or less with respect to the emission intensity Ir at the maximum emission peak wavelength Lr in the wavelength range exceeding 650 nm. The emission intensity ratio of Iv / Ir is 0.002 or less, and the emission of light having an emission peak wavelength of 650 nm or less is suppressed.

FIG. 8 is a partially enlarged view of the emission spectrum shown in FIG. 7, showing the emission spectrum in the wavelength range from around 400 nm to 650 nm or less of the light emitting device according to the second embodiment. In the light emitting device according to the second embodiment, no peak could be confirmed in the range of 400 nm or more and less than 500 nm in the light emitting spectrum, and the light from the light emitting element was hardly emitted to the outside. Further, in the light emitting device according to the second embodiment, the light emitting intensity Iv at the emission peak wavelength Lv in the wavelength range of 400 nm or more and 650 nm is also extremely higher than the emission intensity Ir at the maximum emission peak wavelength Lr in the wavelength range exceeding 650 nm. In the light emitting device according to the second embodiment, the emission of light having an emission peak wavelength of 650 nm or less is suppressed.

FIG. 9 shows the emission spectrum of the light emitting device according to the third embodiment. In the emission spectrum, the light emitting apparatus according to the third embodiment has an emission intensity Iv at the maximum emission peak wavelength Lv in the wavelength range of 400 nm or more and 650 nm or less with respect to the emission intensity Ir at the maximum emission peak wavelength Lr in the wavelength range exceeding 650 nm. The emission intensity ratio of Iv / Ir is 0.005 or less, and the emission of light having an emission peak wavelength of 650 nm or less is suppressed.

FIG. 10 is a partially enlarged view of the emission spectrum shown in FIG. 9, and shows an emission spectrum in a wavelength range from around 400 nm to 650 nm or less of the light emitting device according to the third embodiment. In the light emitting device according to the third embodiment, the light emitting intensity at the light emitting peak wavelength Le of the light emitting element existing in the range of 400 nm or more and less than 500 nm in the light emitting spectrum is also at the maximum light emitting peak wavelength Lv existing in the wavelength range of 400 nm or more and 650 nm or less. Since the emission intensity Iv is also very small with respect to the emission intensity Ir at the maximum emission peak wavelength Lr in the wavelength range exceeding 650 nm, the light emitting device according to the third embodiment emits light in the wavelength range of 650 nm or less. Even in this case, the operation of the light emitting device can be confirmed in a state where the glare of the light emitted from the light emitting device is reduced.

The light emitting device of the present disclosure can be suitably used for various sensors including an infrared sensor, a traffic light, an illumination switch, various indicators and the like.

11, 12: Light emitting element, 21: 1st lead, 22: 2nd lead, 41: 1st base, 41r: 1st recess, 42: Substrate, 43, 45: Resin molded part, 44: 2nd base , 44r: 1st recess, 50: fluorescent member, 50r: 2nd recess, 60: reflective member, 70: phosphor, 80: 1st film, 90: 2nd film, 100, 101, 102: light emitting device.

Claims (11)

A light emitting element that emits visible light and / or ultraviolet light,
A fluorescent member including a phosphor that is excited by the light emitted from the light emitting element and emits light having an emission peak wavelength in a range exceeding 650 nm.
A first film on the optical path of light emitted from the light emitting element, which is arranged on the light emitting side of the fluorescent member, absorbs light having a wavelength of 650 nm or less, and transmits light having a wavelength exceeding 650 nm. With
The first film is a light emitting device in which the thickness of a portion facing the light emitting element is larger than the thickness of a portion not facing the light emitting element. The fluorescent member contains a first resin and contains
The light emitting device according to claim 1, wherein the first film comprises a second resin and a light absorber that absorbs light of 650 nm or less. The phosphors include a phosphor having a composition of a rare earth aluminate containing Ce and Nd, a phosphor having a composition of aluminum oxide containing Cr, a phosphor having a composition of aluminum oxide containing Cr and Ga, and Ce. The light emitting device according to claim 1 or 2, which comprises at least one selected from the group consisting of phosphors having a composition of a phosphor having a composition of a rare earth aluminate containing Er. The light emitting device according to any one of claims 1 to 3, wherein a second film is provided on the light emitting side of the first film. The base is provided, and the base has a first recess having an inner bottom surface and an inner side surface.
The light emitting element is arranged on the inner bottom surface of the first recess of the base.
The fluorescent member is arranged so as to cover a light emitting element arranged on the inner bottom surface of the first recess of the base, and includes a second recess recessed in the direction of the inner bottom surface of the first recess.
The light emitting device according to any one of claims 1 to 4, wherein the first film is arranged in contact with a second recess of the fluorescent member. The process of preparing a base having a first recess having an inner bottom surface and an inner side surface, and
The process of arranging the light emitting element on the inner bottom surface of the base and
A first resin composition containing a first resin and a phosphor which is excited by light emitted from the light emitting element and emits light having an emission peak wavelength in a range exceeding 650 nm in the first recess of the base. To form a fluorescent member covering the light emitting element by filling and curing the light emitting element.
The step of modifying the surface of the fluorescent member and
A second resin composition containing a second resin and a light absorber that absorbs light of 650 nm or less is placed in contact with the fluorescent member whose surface has been modified, and the second resin composition is prepared. A method for manufacturing a light emitting device, which includes a step of curing and arranging a first film. In the step of forming the fluorescent member, forming a fluorescent member having a second recess formed by shrinkage of the first resin composition during curing, which is recessed in the direction of the inner bottom surface of the base.
The method for manufacturing a light emitting device according to claim 6, wherein in the step of modifying the surface, the surface of the fluorescent member including the inner surface of the second recess is modified. The method for manufacturing a light emitting device according to claim 6 or 7, wherein the reforming treatment is any of plasma treatment, corona discharge treatment, and ozone water treatment. The method for manufacturing a light emitting device according to any one of claims 6 to 8, wherein in the step of forming the fluorescent member, the first resin composition is dropped and filled in the first recess. The method for manufacturing a light emitting device according to any one of claims 7 to 9, wherein in the step of arranging the first film, the second resin composition is dropped into the second recess and arranged. The method for manufacturing a light emitting device according to any one of claims 7 to 10, further comprising a step of arranging a second film on the light emitting side of the first film.

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