JP2023112922A - Light-emitting device - Google Patents

Abstract

To provide a light-emitting device in which an occupied area of a plurality of submounts on a substrate in a plan view can be reduced.SOLUTION: A light-emitting device comprises: a substrate; a plurality of submounts provided on the substrate; and a plurality of laser light-emitting elements that are mounted on the plurality of submounts, respectively, and emit a plurality of laser beams, respectively. A plurality of length directions of the plurality of laser light-emitting elements are crossed in a plan view to the plurality of length directions of the plurality of submounts.SELECTED DRAWING: Figure 1

Description

The present disclosure relates to light emitting devices.

As disclosed in Patent Document 1, a plurality of laser beams emitted from a plurality of laser light emitting elements are reflected by a single mirror portion and then superimposed on a wavelength conversion member to improve laser output. A light-emitting device that emits light is being developed.

WO2021/251233

According to the technique disclosed in Patent Document 1 described above, a plurality of laser light emitting elements are installed so that a plurality of laser beams are superimposed by the wavelength conversion member. In Patent Document 1, the longitudinal directions of the plurality of laser light emitting elements are arranged in parallel with the longitudinal directions of the plurality of submounts. In addition, the plurality of submounts themselves are arranged on the substrate so that their longitudinal directions intersect with each other in plan view so that the plurality of laser light emitting elements in the plurality of longitudinal directions point to substantially the same position in the mirror section. . For this reason, the area occupied by the plurality of submounts on the substrate in plan view becomes large, and as a result, there arises a problem that miniaturization of the entire light emitting device is hindered (Problem 1).

The present disclosure has been made in view of Problem 1 described above. A first object of the present disclosure is to provide a light-emitting device capable of reducing the area occupied by a plurality of submounts on a substrate in plan view.

Moreover, according to the technique disclosed in the above-described Patent Document 1, the amount of heat generated in the wavelength conversion member increases due to the superimposition of a plurality of laser beams. As a result, there arises a problem that the light-emitting device malfunctions due to heat generation in the wavelength conversion member (Problem 2).

The present disclosure has been made in view of Problem 2 described above. A second object of the present disclosure is to provide a light-emitting device capable of suppressing the occurrence of defects caused by heat generation in the wavelength conversion material.

In order to solve the above problem 1, a first aspect of the light emitting device of the present disclosure includes a substrate, a plurality of submounts provided on the substrate, each mounted on the plurality of submounts, and and a plurality of laser light emitting elements each emitting a plurality of laser beams, wherein the plurality of length directions of the plurality of laser light emitting elements respectively intersect the plurality of length directions of the plurality of submounts in plan view. .

In order to solve the above-mentioned problem 2, a second aspect of the light emitting device of the present disclosure includes a plurality of laser light emitting elements that respectively emit a plurality of laser beams, a mirror portion that reflects the plurality of laser beams, and the mirror a window member that transmits the plurality of laser beams reflected by a portion; a wavelength conversion member that is irradiated with the plurality of laser beams that have passed through the window member; and the plurality of laser elements surrounding the window member, and a cap member provided to cover the mirror section, the cap member having a thermal conductivity higher than that of the wavelength conversion member.

FIG. 4 is a cross-sectional view of the light-emitting device of Embodiment 1, taken along line II of FIGS. 2 and 3. FIG. FIG. 4 is a vertical cross-sectional view of the light emitting device of Embodiment 1, taken along line II-II of FIGS. 1 and 3. FIG. FIG. 3 is a vertical cross-sectional view of the light emitting device of Embodiment 1, taken along line III-III of FIGS. 1 and 2. FIG. 4 is a graph showing the relationship between the rotation angle of the length direction of the laser light emitting elements with respect to the reference direction and the distance between the laser light emitting elements in plan view of the light emitting device of Embodiment 1. FIG. 4 is a diagram showing a plurality of irradiation regions of a plurality of laser beams in the wavelength conversion material of the light emitting device of Embodiment 1; FIG. FIG. 6 is a diagram showing the relationship between the position of the light emitting device of Embodiment 1 and the beam intensity, showing the distribution of the beam intensity of the laser light on the line AB of FIG. 5; 4A to 4C are diagrams for explaining a manufacturing process of the laser light emitting element and the submount of the light emitting device of Embodiment 1; FIG. FIG. 1 is a first diagram for explaining a manufacturing process of a light emitting device of a comparative example; FIG. 2 is a second diagram for explaining the manufacturing process of the light emitting device of the comparative example; FIG. 10 is a cross-sectional view of a light-emitting device of Modification 1 of Embodiment 1; FIG. 10 is a cross-sectional view of a light emitting device of Modification 2 of Embodiment 1; FIG. 11 is a vertical cross-sectional view of the light emitting device of Embodiment 2, taken along line XII-XII of FIG. 10; FIG. 10 is a diagram showing a plurality of irradiation regions of a plurality of laser beams in the wavelength conversion material of the light emitting device of Embodiment 2; FIG. 16 is a lateral cross-sectional view of the light-emitting device of Embodiment 3, taken along line XIV-XIV of FIG. 15; FIG. 14 is a vertical cross-sectional view of the light emitting device of Embodiment 3, and is a cross-sectional view taken along line XV-XV of FIG. 14; FIG. 11 is a vertical cross-sectional view of the light-emitting device of Embodiment 4, taken along line XVI-XVI of FIG. 10; FIG. 11 is a vertical cross-sectional view of a light-emitting device according to Embodiment 5; FIG. 10 is a vertical cross-sectional view of the light emitting device of Embodiment 6, taken along line XVIII-XVIII in FIG. 1; FIG. 20 is a perspective view of a mirror portion of the light emitting device of Embodiment 6; FIG. 10 is a vertical cross-sectional view of a light-emitting device of a modification of Embodiment 6, taken along the line XX-XX of FIG. 1; FIG. 21 is a perspective view of a mirror portion of a light-emitting device of a modified example of Embodiment 6; FIG. 11 is a cross-sectional view of a light-emitting device of Embodiment 7; FIG. 20 is a cross-sectional view of a light-emitting device of Modification 1 of Embodiment 7; FIG. 21 is a cross-sectional view of a light-emitting device according to Modification 2 of Embodiment 7;

The light emitting device of the present disclosure will be described below with reference to the drawings. In the drawings, the same or equivalent elements are denoted by the same reference numerals, and redundant description of the same or equivalent elements will not be repeated.

In this specification, the term "longitudinal direction" in plan view includes the direction along the long side direction of a rectangle, and the direction along the lengthwise direction of a flat shape such that the length and width can be specified. (or parallel direction). In this specification, the term "width direction" in plan view includes the direction along the short side direction of the rectangle (or parallel direction), and the width direction of the plane shape such that the length and width can be specified. including directions along

As used herein, the term "parallel" does not mean mathematically parallel, but is intended to be manufactured in parallel by design and is subject to manufacturing tolerances. It means that it may be parallel including As used herein, the term "orthogonal" does not mean mathematically orthogonal, but is intended to be manufactured orthogonal by design, It means that they may be orthogonal so as to include an error.

As used herein, the terms "cuboid" and "rectangle" do not mean cuboids and rectangles in the geometric sense. In this specification, rectangular parallelepipeds and rectangular shapes with chamfered or rounded corners are included in rectangular parallelepipeds and rectangles.

In this specification, the term "mirror symmetry" is intended to manufacture not only geometric mirror symmetry but also mirror symmetry in design, and includes errors that may occur in manufacturing , which means that it includes those provided almost mirror-symmetrically.

In some drawings of the embodiments, the trajectory of the laser beam L is indicated by a dotted line. This is because the laser light L originally travels straight while expanding. However, in some drawings, for the sake of simplification, only the ray trajectory at the center of the spread of the laser light L is indicated by an arrow.

(Embodiment 1)
A light-emitting device P according to Embodiment 1 will be described with reference to FIGS. 1 to 10. FIG.

FIG. 1 is a cross-sectional view of a light-emitting device P according to the present embodiment, taken along line II of FIGS. 2 and 3. FIG. FIG. 2 is a vertical cross-sectional view of the light emitting device P of this embodiment, taken along line II-II of FIGS. 1 and 3. FIG. FIG. 3 is a vertical cross-sectional view of the light-emitting device P of this embodiment, taken along line III-III of FIGS. 1 and 2. FIG.

As shown in FIGS. 1 to 3, the light emitting device P includes a substrate S, a plurality of submounts SM, a plurality of laser light emitting elements LD, a mirror portion M, a window member W, a wavelength conversion member WC, and a cap member CA. I have.

Substrate S is a plate-like member, and in the present embodiment, has concave portion CO extending from main surface PS to a predetermined depth. A plurality of submounts SM are provided on the substrate S. As shown in FIG. The plurality of submounts SM has a submount SM1 and a submount SM2. Both the submount SM1 and the submount SM2 are rectangular parallelepipeds and rectangular in plan view. In addition, the substrate S may have a side wall portion rising from the outer peripheral portion of the flat plate.

A plurality of laser light emitting elements LD are respectively mounted on a plurality of submounts SM. Specifically, a plurality of laser emitting elements LD are mounted on a plurality of submounts SM in a one-to-one relationship. The plurality of laser light emitting elements LD has a laser light emitting element LD1 and a laser light emitting element LD2.

The laser light emitting element LD1 emits laser light L1 parallel to its length direction. The laser light emitting element LD2 also emits laser light L2 parallel to its length direction. Both the laser light emitting devices LD1 and LD2 are semiconductor light emitting devices.

A plurality of laser light emitting elements LD1 and LD2 are arranged mirror-symmetrically with respect to a virtual plane. The aforementioned imaginary plane is, for example, a plane perpendicular to the longitudinal direction of the mirror portion M, which is assumed to exist between the laser light emitting elements LD1 and LD2. A virtual plane is a plane that serves as a reference for mirror symmetry. The mirror portion M provided in the recess CO has a rectangular reflecting surface MS. Mirror portion M reflects each of the plurality of laser beams LD1 and LD2 on reflecting surface MS.

The window member W is formed of a transparent member that allows the plurality of laser beams L1 and L2 reflected by the mirror portion M to pass therethrough. The wavelength converting member WC converts the wavelength of each of the plurality of laser beams L1 and L2 reflected by the mirror portion M and transmits them. The wavelength conversion member WC contains phosphor. The wavelength converting member WC converts the wavelength of the laser beam L. As shown in FIG.

The cap member CA is provided so as to surround the window member W and cover the plurality of laser elements LD and the mirror portion M. As shown in FIG. The cap member CA includes a ceiling portion T facing the main surface PS of the substrate S and side wall portions SW rising from the main surface PS of the substrate S to the ceiling portion T. As shown in FIG.

The cap member CA has thermal conductivity higher than that of the wavelength conversion member WC. The cap member CA has thermal conductivity higher than that of the window member W. As shown in FIG. The thermal conductivity of the cap member CA is 50 W/(m·K) or more. The cap member CA is made of metal, metal alloy, or silicon. The metal is, for example, aluminum or copper, and the metal alloy is, for example, an aluminum alloy or a copper alloy.

The cap member CA is in contact with the wavelength conversion member WC. The cap member CA is arranged so as to block the traveling of the plurality of laser beams L1 and L2 in the peripheral portion. The cap member CA has a ceiling portion T and a side wall portion SW. It may be shaped or lid-shaped.

A plurality of length directions of the plurality of laser light emitting elements LD respectively intersect a plurality of length directions (X-axis direction) of the plurality of submounts SM in a plan view. That is, the length direction of the laser light emitting element LD1 intersects the length direction (X-axis direction) of the submount SM1 in plan view. The length direction of the laser light emitting element LD2 intersects the length direction (X-axis direction) of the submount SM2 in plan view. Further, the length directions (X-axis direction) of the plurality of submounts SM are parallel to each other in plan view. Furthermore, each of the plurality of length directions (X-axis direction) of the plurality of submounts SM intersects perpendicularly with the length direction (Y-axis direction) of the mirror section M in plan view.

More specifically, the light emitting device P has the following configuration.

A laser light emitting element LD1, which is rectangular in plan view, is placed on a submount SM1, which is rectangular in plan view, via solder. The laser light emitting element LD1 emits laser light L1 parallel to the length direction of the laser light emitting element LD1, that is, the long side direction of the rectangle. The laser light emitting element LD2, which is rectangular in plan view, is placed on a submount SM2, which is rectangular in plan view, via solder. The laser light emitting element LD2 emits laser light L2 parallel to the length direction of the laser light emitting element LD2, that is, the long side direction of the rectangle.

In a plan view of the light emitting device P, the length direction of the laser light emitting element LD1, that is, the traveling direction of the laser light L1 is inclined by an angle θ1 with respect to the length direction (X-axis direction) of the submount SM1. In addition, in a plan view of the light emitting device P, the length direction of the laser light emitting element LD2, that is, the traveling direction of the laser light L2 is inclined by an angle θ2 with respect to the length direction (X-axis direction) of the submount SM2. The angle θ1 has the same absolute value as the angle θ2, but the positive and negative signs are opposite. That is, θ2=-θ1. Note that the absolute values of θ1 and θ2 may not be the same in a strict sense, and may have differences due to manufacturing errors as long as they are intended to be the same. .

Regarding the laser light emitting element LD1, in a plan view, one corner A1L in the width direction, that is, the short side direction of the rectangle is larger than the other corner A1R in the width direction, and the end face in the length direction of the submount SM1 is larger than the other corner A1R in the width direction. It protrudes from E1. Regarding the laser light emitting element LD2, in a plan view, one corner A2R in the width direction, that is, the short side direction of the rectangle is larger than the other corner A2L in the width direction, and the length direction of the submount SM2 is greater than the other corner A2L in the width direction. It protrudes from the end face E2 in . According to this, the emission points of the laser beams L1 and L2 of the laser light emitting elements LD1 and LD2 are located at positions protruding from the end faces E1 and E2 of the submounts SM1 and SM2, respectively. Therefore, the sub-mounts SM1 and SM2 are provided at positions deviated from the paths of the laser beams L1 and L2, which travel while spreading from the emission point, and therefore do not hinder the progress of the laser beams L1 and L2.

The length direction (X-axis direction) of the submount SM1 is perpendicular to the length direction (Y-axis direction) of the reflecting surface MS of the mirror section M in plan view. Therefore, in a plan view of the light emitting device P, the length direction of the laser light emitting element LD1 is the short side direction of the mirror portion M (that is, the submount It is inclined by a rotation angle θ1 with respect to the X-axis direction (which is the length direction of SM1). In a plan view of the light emitting device P, the length direction of the laser light emitting element LD2 is the short side direction of the mirror portion M (that is, It is inclined by a rotation angle θ2 with respect to the X-axis direction). The laser light emitting element LD1 and the laser light emitting element LD2 are arranged mirror-symmetrically with respect to a plane (ZX plane) perpendicular to the length direction (Y-axis direction) of the reflecting surface MS of the mirror portion M.

The laser light emitting elements LD1 and LD2 are laser diode (LD) chips that emit laser light L1 and L2 with a wavelength of 450 nm, respectively. Although not shown, this chip is formed of a diode having pn junctions in the vertical direction, and polar electrodes are provided on the upper and lower surfaces of the chip.

Although not shown, the light-emitting device P electrically connects metal wire lines drawn from both positive and negative electrodes of a diode constituting a chip, wiring on the substrate S, and the metal wire lines and external equipment. Wiring etc. for connection are provided.

Laser beams L1 and L2 emitted from laser light emitting elements LD1 and LD2 are reflected by mirror portion M toward window member W of cap member CA, respectively. The window member W is provided with a phosphor light emitting member functioning as a wavelength converting member WC in a space on the opposite side of the space where the laser light emitting elements LD1 and LD2 are present. Each of the laser beams L1 and L2 is irradiated to the phosphor light emitting member forming the wavelength conversion member WC. As a result, wavelength conversion of each of the laser beams L1 and L2 occurs.

A plate-shaped single-crystal phosphor, various known phosphor plates, a phosphor layer, or a printed film containing phosphor particles can be used as the phosphor light-emitting member. In this embodiment, a single crystal YAG (Yttrium Aluminum Garnet) phosphor plate is used as the phosphor light emitting member.

The wavelength conversion member WC of this embodiment is a member containing a phosphor. However, the wavelength conversion member WC is, for example, a transparent base material (eg, sapphire (Al ₂ O ₃ plate), on which phosphor powder (eg, YAG phosphor powder) is adhered with a binder). Also, the wavelength conversion member WC contains a transparent base material such as a transparent base material on which a film containing phosphor particles is printed, and a phosphor provided on the lower surface or the upper surface thereof. In the present embodiment, not only the part containing the phosphor etc., but also the part containing the phosphor etc. and the transparent base material are integrated. , is the wavelength converting member WC.

For example, in the present specification, a single crystal, polycrystal, or ceramic phosphor plate or phosphor sheet attached to and supported by a transparent base material (sapphire plate) is also referred to as a transparent base material. is called a wavelength conversion member WC. Furthermore, for example, a wavelength conversion member WC having a printed film containing a phosphor formed on a sapphire plate is placed or attached to the window member W so that the sapphire plate and the window member W are in contact with each other. may

In addition, it is preferable that the size of the wavelength conversion member WC is the same as or larger than the size of the window member W in plan view. In other words, it is preferable that the wavelength conversion member WC has the same shape as the window member W or a shape that covers the entire window member W in plan view.

The mirror portion M is, for example, a triangular prism whose cross section forms an isosceles right triangle. The triangular prism-shaped mirror portion M has a reflecting surface MS that forms an angle of 45 degrees with respect to the main surface PS of the substrate S. As shown in FIG. Reflective surface MS is a plane. The mirror portion M changes the direction of travel of the laser beams L1 and L2. The mirror portion M may be made of a metal with high reflectance, such as aluminum or silver. Also, the mirror portion M may be made of any material having a dielectric multilayer mirror portion provided on its surface. Mirror portion M is provided in concave portion CO formed from main surface PS of substrate S to a predetermined depth. Note that the shape of the mirror portion M is not limited to a triangular prism. One side surface of another polygonal prism may be used as the mirror portion, or a planar portion of a flat plate may be used as the mirror portion.

In this embodiment, the mirror section M is a member independent of the substrate S and the cap member CA, but may be a part of the substrate S or a part of the cap member CA. good too.

A plurality of irradiation regions LDS1 and LDS2 (see FIG. 5) of a plurality of laser beams L on the surface of the wavelength conversion member WC are elliptical due to the characteristics of the semiconductor laser. The following can be said for the irradiation regions LDS1 and LDS2 of the plurality of laser beams L on the wavelength conversion member WC. A plurality of laser beams L are applied to the wavelength conversion member WC such that at least a portion of one laser beam LDS1 out of the plurality of laser beams L overlaps at least a portion of another laser beam LDS2 out of the plurality of laser beams L. be irradiated.

The plurality of laser beams L are applied to the wavelength conversion member WC so that the plurality of length directions (major axis directions of the ellipse) of the plurality of irradiation regions LDS1 and LDS2 of the plurality of laser beams L are parallel to each other. be irradiated.

The plurality of laser beams are emitted so that the plurality of incident angles of the plurality of laser beams L with respect to the reflecting surface MS of the mirror portion M are different from each other, specifically, the incident angles are opposite in sign and have the same absolute value. A device LD is arranged with respect to the mirror portion M. As shown in FIG.

The cap member CA of the present embodiment is formed by providing a concave portion in a plate-like silicon. The cap member CA is provided so as to cover the main surface PS of the substrate S with the bottom portion of the recess as the ceiling portion T and the side wall portion of the recess as the side wall portion SW. A ceiling portion T of the cap member CA has a window member W. As shown in FIG. The window member W is formed by fitting transparent glass into the opening of the cap member CA.

The cap member CA may be made of a high thermal conductive material other than silicon (having a thermal conductivity of 148 [W/(m·K)]). For example, the cap member CA may be made of aluminum <237 [W/(m·K)]>, copper <398 [W/(m·K)], or the like. The material constituting the ceiling portion T of the cap member CA surrounding the window member W is selected from the viewpoint of increasing the efficiency of discharging heat generated by the wavelength conversion member WC (phosphor light emitting member). It is preferably made of material. More specifically, the thermal conductivity of the cap member CA must be higher than that of the wavelength conversion member WC. The cap member CA is preferably 50 [W/(m·K)] or more.

Generally, the thermal conductivity of YAG used as a phosphor is about 10 [W/(mK)], and the thermal conductivity of sapphire (Al ₂ O ₃ ) that can be used as its supporting member is about 40 [W/(m·K)]. W/(m·K)]. Therefore, using a material with a thermal conductivity of 50 [W/(m·K)] as the material for the top portion T of the cap member CA has the function of effectively discharging the heat generated by the wavelength conversion member WC. can be said to have

This cap member CA is joined to the substrate S by soldering. The heat generated by the wavelength conversion member WC is preferably transmitted to the substrate S from the lower surfaces of the side wall portions SW of the cap member CA via the ceiling portion T of the cap member CA. In other words, it is preferable that there is no member interfering with the conduction and transmission of heat between the ceiling portion T of the cap member CA and the substrate S.

The window member W may be made of any material that is transparent to the laser light L, such as glass, plastic, or sapphire, but is preferably made of a material with high heat resistance. . The wavelength converting member WC (phosphor emitting member) may be of any type as long as it converts the wavelength of the laser light L. FIG. The light-emitting device P of the present embodiment has a wavelength conversion member WC that converts blue laser light L of 450 nm into white light using a phosphor light-emitting member and functions as a white light source.

The two laser beams L1 and L2 emitted from the laser light emitting elements LD1 and LD2 are reflected by the mirror portion M to change their traveling directions. After that, the mirror portion M is arranged so that the two laser beams L1 and L2 partially overlap each other on the surface of the wavelength conversion member WC on the window member W side.

FIG. 4 shows the absolute values of the rotation angles θ1 and θ2 of the length direction of the laser light emitting element LD with respect to the reference direction (X-axis direction) in the plan view of the light emitting device P of Embodiment 1, and the laser light emitting element LD1. It is a graph which shows the relationship with the distance D between laser light emitting elements LD2. 1 and 3, the distance D is the distance between the emission point of the laser light L1 of the laser light emitting element LD1 and the emission point of the laser light L2 of the laser light emitting element LD2.

It is assumed that the distance from the light emitting point of each of the laser light emitting elements LD1 and LD2 to the mirror section M is 0.25 mm. The distance from the central portion of the mirror portion M irradiated with the laser light L to the lower surface of the phosphor light-emitting member as the wavelength conversion member WC is assumed to be 0.80 mm. The angle of inclination of the reflection surface MS of the mirror portion M with respect to the main surface PS of the substrate S is assumed to be 45 degrees. It is also assumed that the mirror portion M is formed of a prism made of glass whose reflection surface MS is coated with silver.

Each of the laser light emitting elements LD1 and LD2 has a width of 0.15 mm (the light emitting point is located at the center in the width direction), a length (resonator length) of 1.2 mm, and a thickness of 0.05 mm. The laser emitting element LD1 or LD2 is mounted on the submount SM1 or SM2 in a junction-down manner. Therefore, the light emitting point of each of the laser light emitting elements LD1 and LD2 exists approximately near the interface between the laser light emitting element LD1 or LD2 and the submount SM1 or SM2. Therefore, the thickness t (see FIGS. 2 and 3) of the laser light emitting element LD does not affect the optical layout.

In the case of this embodiment, two laser light emitting elements LD1 and LD2 are used. Let the distance be D (see FIGS. 1 and 3). Also, let θ1 be the rotation angle of the length direction of the laser light emitting element LD1 with respect to the length direction (X-axis direction) of the submount SM1. Also, let θ2 be the rotation angle of the length direction of the laser light emitting element LD2 with respect to the length direction (X-axis direction) of the submount SM2. Here, it is assumed that θ1=-θ2. More specifically, D=0.34 mm and θ1=−θ2=14.5°. The wavelength converting member WC is irradiated with the two laser beams L1 and L2 such that the output peaks of the laser beams L1 and L2 emitted from the two laser light emitting elements LD1 and LD2 overlap on the lower surface of the wavelength converting member WC. and

The radiation angles (full angles) of the laser beams L1 and L2 of the laser elements LD1 and LD2 of the present embodiment are such that the major axis direction of the elliptical beam is 42° (1/e^2) and the elliptical beam The short axis direction of the shaped beam is 10° (1/e^2). A spot of elliptical laser beams L1 and L2 having a long axis direction of 1.03 mm and a short axis direction of 0.25 mm is irradiated onto the lower surface of the phosphor light emitting member constituting the wavelength conversion member WC. That is, in this case, the phosphor light emitting member forming the wavelength conversion member WC functions as an elliptical white light source with a major axis of 1.03 mm and a minor axis of 0.25 mm.

Here, the rotation angle θ1 of the laser light emitting device LD1 and the rotation angle θ2 of the laser light emitting device LD2 may be any values. However, in order for the two laser beams L1 and L2 to overlap on the lower surface of the phosphor light emitting member that constitutes the wavelength conversion member WC, as the rotation angles θ1 and θ2 increase, the distance between the laser light emitting elements LD1 and LD2 increases. It is necessary to increase the distance D between

If the absolute value of the rotation angle θ1 of the laser light emitting element LD1 and the absolute value of the rotation angle θ2 of the laser light emitting element LD2 are too small, the distance D between the laser light emitting elements LD1 and LD2 becomes too small. In general, in order to precisely mount the two submounts SM1 and SM2 on the substrate S, it is preferable that the distance D between the submounts SM1 and SM2 is 0.1 mm or more. If the distance D between submount SM1 and submount SM2 is 0.1 mm, the rotation angles θ1 and θ2 should be about 4°. Therefore, it is preferable that the absolute value of the rotation angle θ1 and the absolute value of the rotation angle θ2 are at least 4° or more.

On the other hand, if the absolute values of the rotation angles θ1 and θ2 are too large, it is necessary to increase the distance D between the laser light emitting elements LD1 and LD2. In this case, the installation areas of the submounts SM1 and SM2 on which the laser light emitting elements LD1 and LD2 are mounted must be increased, resulting in the problem of hindering the downsizing of the entire light emitting device. Therefore, the absolute values of the rotation angles θ1 and θ2 are both preferably within 45°.

Further, the laser light emitting devices LD1 and LD2 are mounted on the submounts SM1 and SM2 so that the two front end portions of the laser light emitting devices LD1 and LD2 protrude from the front end faces of the submounts SM1 and SM2 (the end face on the side of the mirror portion M). It is preferable to install In this case, the following can be said for each of the plurality of laser light emitting elements LD1 (LD2). In plan view, one corner A1L (A2R) in the width direction is larger than the other corner A1R (A2L) in the width direction, and the end face E1 ( It preferably protrudes from E2). According to this, the radiation distributions of the laser beams L1 and L2 emitted from the laser light emitting elements LD1 and LD2 are symmetrical in the thickness direction t of the laser light emitting elements LD1 and LD2.

FIG. 5 is a diagram showing a plurality of irradiation regions LDS1 and LDS2 of a plurality of laser beams L in the wavelength conversion material WC of the light emitting device P of this embodiment.

FIG. 5 is a diagram showing the light emitting device P when viewing the cap member CA along the Z-axis direction at the position where the phosphor light emitting member as the wavelength converting member WC is installed. In other words, FIG. 5 is a cross-sectional view when the cap member CA is removed from the light emitting device P and the ceiling portion T of the cap member CA is viewed from the inside of the cap member CA. At the position of the window member W, the lower surface of the phosphor light emitting member as the wavelength conversion member WC can be seen through the glass of the window member W. FIG.

Almost all of the two laser beams L1 and L2 emitted from the laser light emitting elements LD1 and L2 are overlapped on the window member W side surface of the phosphor light emitting member as the wavelength conversion member WC. Thus, laser light emitting elements LD1 and L2 are arranged on submount SM1 and submount SM2, respectively.

A dashed ellipse and a dashed line ellipse indicate the irradiation regions LDS1 and LDS2 of the laser beams L1 and L2. If the irradiation regions LDS1 and LDS2 of the two laser beams L1 and L2 are completely overlapped, the existence of the two irradiation regions LDS1 and LDS2 cannot be recognized. is drawn in a slightly shifted position.

By overlapping the two irradiation regions LDS1 and LDS2 in this manner, the light density of the laser beams L1 and L2 that excite the phosphor light emitting member as the wavelength conversion member WC can be increased up to twice. Therefore, the light source luminance of the white light emitted from the phosphor light emitting member as the wavelength conversion member WC can be increased up to two times. Further, the total luminous flux of white light emitted from the phosphor light-emitting member as the wavelength conversion member WC can be increased, for example, by a maximum of two times. As a result, it is possible to further improve the characteristics of the light source with a simple configuration.

The shape of the beams emitted from the laser light emitting elements LD1 and LD2 is elliptical. Therefore, as shown in FIG. 5, the irradiation regions LDS1 and LDS2 of the laser light irradiated to the wavelength conversion member WC also have an elliptical shape with the long axis in the X-axis direction. The overlapping area of the two irradiation areas LDS1 and LDS2 of the two laser beams emitted from the laser light emitting elements LD1 and LD2 also has a substantially elliptical shape reflecting the beam shape.

The window member W provided in the ceiling portion T of the cap member CA is provided in conformity with a substantially elliptical shape generated by overlapping the two laser light irradiation regions LDS1 and LDS2.

FIG. 6 is a diagram showing the relationship between the position of the light emitting device P and the beam intensity according to this embodiment, and shows the distribution of the beam intensity of the laser light on line AB in FIG.

As shown in FIG. 6, the size and shape of the wavelength conversion member WC shall correspond to the size and shape of the window member W, respectively. Further, the light distribution of the laser beams L1 and L2 in a substantially elliptical spot generated by overlapping the irradiation areas LDS1 and LDS2 of the two laser beams L1 and L2 is Gaussian distribution.

The window member W has a size through which a beam having an intensity equal to or greater than 1/ê2 of the peak intensity in the Gaussian distribution of the beam passes. That is, at the peripheral end portion of the beam having an intensity of 1/e^2 or less, the laser beams L1 and L2 are blocked by the ceiling portion T of the cap member CA, and the beam intensity of the laser beams L1 and L2 is approximately 86%. passes through the window member W. In FIG. 6, the position between the hatched members (cap members CA) shown at the bottom of the graph is the position of the window member W schematically shown. In this way, the traveling of the laser beams L1 and L2 in the outer peripheral portion is blocked. Thereby, the light emission size and shape of the phosphor light emitting member, which is the wavelength converting member WC, are clearly defined. As a result, the edges of the light source are sharpened, thus reducing the variation in light source size.

As described above, according to the light-emitting device P of the present embodiment, since the plurality of laser irradiation regions LDS1 and LDS2 can be overlapped with the wavelength conversion member WC (phosphor light-emitting member), the luminance of the wavelength conversion member WC is and the total luminous flux can be increased. However, since the optical density of the laser beams L1 and L2 at the wavelength conversion member WC increases several times, the heat generation at the wavelength conversion member WC becomes significant. Therefore, it is desirable to simultaneously take heat dissipation measures in the wavelength conversion member WC. Therefore, in the present embodiment, the heat generated in the window member W provided in the ceiling portion T of the cap member CA is discharged through the high thermal conductivity material forming the ceiling portion T of the cap member CA. As a result, it becomes possible to practically increase the luminance and the luminous flux of the wavelength conversion member WC by superimposing the laser beams L1 and L2.

Also, a plurality of submounts SM1 and SM2 can be arranged parallel to each other. Therefore, the installation area of the plurality of submounts SM1 and SM2 on the substrate S can be reduced compared to the case where the plurality of submounts SM1 and SM2 are arranged so as to cross the plurality of longitudinal directions. As a result, the light emitting device P can be miniaturized.

Furthermore, in the manufacturing process of the light emitting device P described above, first, the laser light emitting elements LD1 and LD2 are arranged in a state in which the length directions of the laser light emitting elements LD1 and LD2 are inclined with respect to the length directions of the submounts SM1 and SM2. LD2 is mounted on submounts SM1 and SM2. After that, the submounts SM1 and SM2 are mounted on the substrate S so that the lengthwise direction of the submounts SM1 and SM2 is perpendicular to the lengthwise direction of the mirror section M.

According to the manufacturing method described above, when the submounts SM1 and SM2 are mounted on the substrate S, the submounts SM1 and SM2 should be arranged parallel to each other. Therefore, the alignment of the submounts SM1 and SM2 with respect to the mirror portion M is facilitated. As a result, the throughput in the manufacturing process of the light emitting device P can be improved. A method for improving the throughput will be specifically described below.

FIG. 7 is a diagram for explaining the manufacturing process of the laser light emitting elements LD1 and LD2 and the submounts SM1 and SM2 of the light emitting device P of the embodiment.

First, in step 1, for each of the laser light emitting devices LD1 and LD2, the rotation angles θ1 and θ2 of the length direction of the laser light emitting devices LD1 and LD2 with respect to the length direction of the submounts SM1 and SM2 are adjusted only once. . Thereby, a first set ST1 of the laser light emitting element LD1 and the submount SM1 and a second set ST2 of the laser light emitting element LD2 and the submount SM2 are respectively prepared in advance. For mass production, a large number of each of the first set ST1 and the second set ST2 are prepared.

Next, in step 2, the first set ST1 and the second set ST2 are mounted on the substrate S so that the length directions of the submounts SM1 and SM2 are parallel to the width direction of the mirror portion M. In mass production, steps 1 and 2 are repeated many times. According to this, since it is not necessary to align each of the laser light emitting elements LD1 and LD2 individually with respect to the mirror portion M, the throughput of the light emitting device P can be improved. In addition, variations in the rotation angles θ1 and θ2 in the length direction of the laser light emitting elements LD1 and LD2 with respect to the length direction of the mirror portion M can be reduced.

FIG. 8 is the first diagram for explaining the manufacturing process of the light emitting device of the comparative example. FIG. 9 is a second diagram for explaining the manufacturing process of the light emitting device of the comparative example.

As shown in FIG. 8, according to the method of manufacturing the light emitting device of the comparative example, the laser light emitting elements LD1 and LD2 are arranged so that the length direction of the laser light emitting elements LD1 and LD2 is parallel to the length direction of the submounts SM1 and SM2. LD1 and LD2 are mounted on submounts SM1 and SM2. Next, as shown in FIG. 9, when a plurality of submounts SM1 and SM2 are mounted on the substrate S, the rotation angles .theta.1 and .theta.2 of the submounts SM1 and SM2 are individually adjusted. A first set ST1 and a second set ST2 are mounted on the substrate S. FIG. This significantly reduces the throughput of the manufacturing process. In addition, variations in the rotation angles θ1 and θ2 increase.

Further, in this embodiment, the two laser light emitting elements LD1 and LD2 are arranged mirror-symmetrically with respect to the ZX plane perpendicular to the mirror portion M (θ2=−θ1). As a result, the two laser irradiation regions LDS1 and LDS2 in the phosphor light emitting member as the wavelength conversion member WC are mirror-symmetrical in the Y-axis direction, that is, with respect to the ZX plane. Therefore, the combined irradiation area in which the two laser irradiation areas LDS1 and LDS2 are superimposed has mirror symmetry in the Y direction, that is, with respect to the ZX plane. Therefore, the light emitting device P is in a favorable state as a light source.

FIG. 10 is a cross-sectional view of a light-emitting device P according to Modification 1 of the present embodiment.

In Modified Example 1, the plurality of laser light emitting elements LD consists of three laser light emitting elements LD11, LD12, and LD13. Three laser light emitting elements LD11, LD12, and LD13 are arranged along the length direction of the mirror portion M in this order. Each of the three laser light emitting elements LD11, LD12, and LD13 emits laser light parallel to its own length direction.

The laser light emitting element LD12 positioned in the center of the three laser light emitting elements LD11, LD12, and LD13 is mounted on the submount SM12 so that the length direction of the laser light emitting element LD12 is parallel to the length direction of the submount SM12. installed in the The length direction of the laser light emitting element LD12 is provided parallel to the width direction of the mirror section M. As shown in FIG.

On the other hand, the laser light emitting element LD11 is mounted on the submount SM11 so as to emit laser light in a direction inclined by a rotation angle θ1 with respect to the length direction of the submount SM11 in plan view. The laser light emitting element LD13 is mounted on the submount SM13 so as to emit laser light in a direction inclined by a rotation angle θ3 with respect to the length direction of the submount SM13 in plan view. Here, θ3=-θ1.

In Modification 1 as well, the three laser beams emitted from the three laser light emitting elements LD11, LD12, and LD13 are reflected by the mirror portion M, the traveling direction is changed, and the phosphor light emitting member as the wavelength conversion member WC At least a part thereof overlaps on the surface on the window member W side.

With the light emitting device P of Modification 1, the same effect as that obtained with the light emitting device P of the present embodiment described above can be obtained.

FIG. 11 is a cross-sectional view of a light-emitting device P of Modification 2 of the present embodiment.

In Modification 2, the plurality of laser light emitting elements LD consists of four laser light emitting elements LD101, LD102, LD103 and LD104. Three laser light emitting elements LD101, LD102, LD103, and LD104 are arranged along the length direction of the mirror portion M in this order. Each of the four laser light emitting elements LD101, LD102, LD103, and LD401 emits laser light parallel to its own length direction.

The laser light emitting element LD101 and the laser light emitting element LD104 are arranged mirror-symmetrically with respect to a plane (ZX plane) orthogonal to the length direction (Y-axis direction) of the reflecting surface MS of the mirror portion M. The laser light emitting element LD102 and the laser light emitting element LD103 are arranged mirror-symmetrically with respect to a plane (ZX plane) perpendicular to the length direction (Y-axis direction) of the reflecting surface MS of the mirror portion M.

Also in Modification 2, the four laser beams emitted from the four laser light emitting elements LD101, LD102, LD103, and LD104 are reflected by the mirror portion M. FIG. Further, the four laser beams have their traveling directions changed, and at least part of them overlap on the window member W side surface of the phosphor light emitting member as the wavelength conversion member WC.

With the light emitting device P of Modification 2, the same effect as that obtained with the light emitting device P of the present embodiment described above can be obtained.

(Embodiment 2)
The light-emitting device of Embodiment 2 will be described with reference to FIGS. 12 and 13. FIG. In the following description, the same description as in the first embodiment will not be repeated.

FIG. 12 is a vertical cross-sectional view of the light-emitting device P of this embodiment, taken along line XII-XII in FIG. FIG. 13 is a diagram showing a plurality of irradiation regions LDS11, LDS12, LDS13 of a plurality of laser beams in the wavelength conversion material WC of the light emitting device P of this embodiment. The light-emitting device P of this embodiment is similar to the light-emitting device P of Modification 1 of Embodiment 1. FIG. However, the light emitting device P of Embodiment 2 differs from the light emitting device P of Modification 1 of Embodiment 1 in the following points.

The laser light emitting element LD12 emits red laser light with a wavelength of 640 nm. Each of the laser light emitting elements LD11 and LD13 emits blue laser light with a wavelength of 450 nm.

In the light-emitting device P of Modification 1 of Embodiment 1, all of the laser light-emitting elements LD11, LD12, and LD13 emit laser light of the same wavelength. of laser light.

The cap member CA is composed of aluminum side walls SW and a ceiling portion T, and the ceiling portion T is provided with a window member W made of heat-resistant plastic.

In this embodiment, the blue laser light emitted by the laser light emitting elements LD11 and LD13 excites the phosphor light emitting member functioning as the wavelength conversion member WC. As a result, the phosphor light-emitting member emits white light. That is, a white point light source is obtained. Also, the red laser light emitted from the laser light emitting element LD12 is irradiated and scattered by the phosphor light emitting member functioning as the wavelength conversion member WC. Thereby, redness can be added to the white light. As a result, a white light source with excellent color rendering can be obtained.

As can be seen from FIG. 12, the wavelength conversion member WC is larger than the window member W in a cross-sectional view and also in a plan view (not shown). Therefore, the wavelength conversion member WC is brought into contact with the cap member CA by overlapping the wavelength conversion member WC on the upper portion of the cap member CA made of the high thermal conductivity material. As a result, heat generated by the wavelength conversion member WC can be efficiently transmitted to the cap member CA.

As shown in FIG. 13, the following can be said about the irradiation regions LDS1, LDS2, and LDS3 of the three laser beams irradiated to the cap member CA side surface of the wavelength conversion member WC. In other words, the irradiation regions LDS1 and LDS3 of the two laser beams emitted from the laser light emitting elements LD1 and LD3 partially overlap each other. As shown in FIG. 13, portions of the irradiation regions LDS1 and LDS3 of the laser beams emitted from the laser light emitting elements LD1 and LD3 are formed at positions shifted in the Y-axis direction. The irradiation area LDS2 of the laser beam emitted from the laser light emitting element LD2 is positioned at the center of the two irradiation areas LDS1 and LDS3 of the two laser beams emitted from the laser light emitting elements LD1 and LD3. Therefore, in plan view, the irradiation areas LDS1, LDS2, and LDS3 of the three laser beams emitted from the laser light emitting elements LD1, LD2, and LD3 have a symmetrical distribution with respect to the Y-axis direction.

With the light emitting device P of the present embodiment described above, the same effect as that obtained by the light emitting device P of the present embodiment described above can be obtained.

A light-emitting device P according to a modification of the present embodiment will now be described. A modified light-emitting device implements laser emitting elements of different wavelengths. Thereby, a function is added to the laser light emitting element.

As shown in FIG. 11, similarly to the light-emitting device P of the second modification of the first embodiment, the light-emitting device P of the modification of the present embodiment includes four laser light-emitting elements LD101, LD102, LD103, and LD104. have the following relationships: In other words, in plan view, the laser light emitting device LD102 and the laser light emitting device LD103 are arranged symmetrically with respect to the X-axis direction. Also, the laser light emitting device LD101 and the laser light emitting device LD104 are arranged symmetrically with respect to the X-axis direction.

The laser light emitted by the laser light emitting element LD102 and the laser light emitting element LD103 is ultraviolet laser light with a wavelength of 405 nm. On the other hand, both the laser light emitting device LD101 and the laser light emitting device LD104 are formed of chips that emit infrared light with a wavelength of 905 nm. The phosphor light-emitting member as the wavelength conversion member WC is formed by mixing a plurality of phosphor materials so that it emits white light when excited by laser light with a wavelength of 405 nm.

According to the light-emitting device P of this embodiment, the ultraviolet laser light emitted from the laser light-emitting elements LD102 and LD103 excites the phosphor light-emitting member. As a result, the phosphor light-emitting member emits white light. That is, a white point light source is obtained. Also, the infrared laser light from the laser light emitting element LD101 and the laser light emitting element LD104 is irradiated to the phosphor light emitting member as the wavelength converting member WC and scattered. Thereby, infrared light can be added to the white light. This infrared light enables optical communication or ranging. Therefore, according to the light emitting device P of this embodiment, other functions can be added to the white light source.

Almost all of the four laser beams emitted from the laser light emitting elements LD101, LD102, LD103, and LD104 overlap on the cap member CA side surface of the phosphor light emitting member as the wavelength conversion member WC.

The light-emitting device P of the modified example of the present embodiment described above can also provide the same effect as the effect obtained by the light-emitting device P of the present embodiment described above.

(Embodiment 3)
A light-emitting device according to Embodiment 3 will be described with reference to FIGS. 14 and 15. FIG. In the following description, the same description as in the first or second embodiment will not be repeated. The light-emitting device of this embodiment differs from the light-emitting device of Embodiment 1 or 2 in the following points.

FIG. 14 is a cross-sectional view of the light-emitting device P of this embodiment, taken along line XIV-XIV of FIG. FIG. 15 is a vertical cross-sectional view of the light-emitting device P of this embodiment, which is a cross-sectional view taken along line XV-XV of FIG.

The two laser beams emitted from the laser light emitting elements LD1 and LD2 of the present embodiment are irradiated obliquely onto the reflecting surface MS of the mirror portion M. As shown in FIG. As a result, the two laser beams are changed in traveling direction, and then the light is irradiated to the wavelength conversion member WC through the window member W of the cap member CA. In these respects, this embodiment is the same as the above-described embodiment.

In this embodiment, no other laser light emitting elements are provided at positions symmetrical to the positions of the laser light emitting elements LD1 and LD2 with respect to the X-axis direction, and the photodiodes PD are arranged instead. is different from the above-described embodiment.

The photodiode PD is for receiving the laser light reflected by the phosphor light-emitting member as the wavelength conversion member WC or the window member W, and monitoring the amount of light and the change in the amount of light with time. The laser beam obliquely incident on the reflecting surface MS of the mirror portion M is reflected by the mirror portion M, and then obliquely incident on the window member W and the wavelength conversion member WC. The laser light is reflected toward the position of the photodiode PD by the window member W and the wavelength conversion member WC. With such arrangement, it is possible to monitor or supervise the status (light amount and time conversion) of the laser light emitted from the laser light emitting elements LD1 and LD2. As a result, the light emitting device P can be driven with stable characteristics.

Note that the photodiode PD may be provided with a filter that allows only the laser light of a specific wavelength emitted from the laser light emitting elements LD1 and LD2 to pass therethrough. According to this, the photodiode PD can receive only the laser light of the wavelength to be monitored.

With the light emitting device P of the present embodiment described above, the same effect as that obtained by the light emitting device P of the present embodiment described above can be obtained.

(Embodiment 4)
A light-emitting device according to Embodiment 4 will be described with reference to FIG. In the following description, the same description as in Embodiments 1 to 3 will not be repeated. The light emitting device of this embodiment differs from the light emitting devices of Embodiments 1 to 3 in the following points.

FIG. 16 is a vertical cross-sectional view of the light-emitting device P of this embodiment, which is a cross-sectional view taken along line XVI-XVI of FIG.

In this embodiment, a light scattering member SC is provided in place of the phosphor light emitting member as the wavelength conversion member WC. The laser light emitting elements LD1, LD2, and LD3 respectively emit red (wavelength: 638 nm), green (wavelength: 520 nm), and blue (wavelength: 455 nm) laser beams forming the three primary colors of light. The light scattering member SC is irradiated so that substantially the entirety of the laser light emitting elements LD1, LD2, and LD3 overlap. When the three colors of laser light are mixed, white laser light is produced. The three laser beams are superimposed by the light scattering member SC and scattered as white light. Thereby, the light scattering member SC functions as a white point light source. In this embodiment, no phosphor is used, so wavelength conversion of laser light is not performed.

The light scattering member SC does not absorb laser light, unlike the phosphor light emitting member. Therefore, no heat is generated. Therefore, it is not necessary to take heat dissipation measures from the light scattering member SC. Therefore, the cap member CA is made of glass (thermal conductivity: 1.0 [W/(m·K)]).

Thus, the light-emitting device P of this embodiment is not only applied to semiconductor laser devices for exciting phosphor light-emitting members. In other words, the light emitting device P of the present embodiment can also be applied to a semiconductor laser device that emits light without using a phosphor, in other words, a semiconductor laser device that emits light without wavelength conversion of laser light. obtain.

With the light emitting device P of the present embodiment described above, the same effect as that obtained by the light emitting device P of the present embodiment described above can be obtained.

(Embodiment 5)
A light-emitting device according to Embodiment 5 will be described with reference to FIG. In the following description, the same description as in Embodiments 1 to 4 will not be repeated. The light emitting device of this embodiment differs from the light emitting devices of Embodiments 1 to 4 in the following points.

FIG. 17 is a longitudinal sectional view of the light emitting device P of the fifth embodiment.

The angle of the reflecting surface MS of the mirror portion M with respect to the main surface PS of the substrate S does not necessarily have to be 45 degrees. The angle of the reflective surface MS of the mirror portion M with respect to the main surface PS of the substrate S is appropriately selected. Thereby, as shown in FIG. 17, the wavelength conversion member WC can be arranged in the center of the ceiling of the cap member CA. In this case, heat generated from the wavelength conversion member WC is evenly conducted from the ceiling of the cap member CA to the surroundings. Therefore, the heat exhaust effect from the wavelength conversion member WC can be improved.

(Embodiment 6)
A light-emitting device according to Embodiment 6 will be described with reference to FIGS. 18 and 19. FIG. In the following description, the same description as in Embodiments 1 to 5 will not be repeated. The light emitting device of this embodiment differs from the light emitting devices of Embodiments 1 to 5 in the following points.

FIG. 18 is a vertical cross-sectional view of the light-emitting device P of Embodiment 6, taken along line XVIII-XVIII in FIG. FIG. 19 is a perspective view of the mirror portion M of the light emitting device P of Embodiment 6. FIG.

In the light-emitting device P of the present embodiment, the reflecting surface MS of the mirror portion M is curved rather than flat. As a result, as shown in FIG. 18, the spread angles (beam divergence angles) of the laser beams L1 and L2 emitted from the plurality of laser light emitting elements LD1 and LD2 are different from each other at the curved mirror portion M. Modified when L1 and L2 are reflected. In this case, the spot size and shape of each of the plurality of laser beams L1 and L2 with which the wavelength conversion section WC is irradiated can be adjusted by designing the curved surface of the mirror section M.

In the present embodiment as well, the plurality of laser beams L1 and L2 emitted from the plurality of laser light emitting elements LD1 and LD2 are superimposed on one wavelength converter W so that the luminance and the total luminous flux in the wavelength converter WC are can be increased. However, if the reflecting surface MS is a curved surface as in the mirror portion M of the present embodiment, not only the plurality of laser beams L1 and L2 are overlapped, but also the plurality of laser beams L1 and L2 are overlapped while condensed. The laser beams L1 and L2 can be spread out and superimposed on each other. For example, if the two laser beams L1 and L2 are superimposed while being condensed, it is possible to obtain light with twice or more brightness while superimposing the two laser beams L1 and L2, that is, to increase the light output. . By superimposing the two laser beams L1 and L2 while spreading them, it is possible to obtain light with less than twice the brightness while superimposing the two laser beams L1 and L2, that is, to suppress a large increase in light output. can be done.

As the profile of the curved surface in the cross section of the reflective surface MS of the mirror portion M, any desired profile such as a part of an ellipse, a part of a parabola, or a free-form curve can be selected according to the purpose.

As shown in FIGS. 18 and 19, when a curved surface that is concave with respect to the laser beams L1 and L2 is selected as the profile of the curved surface of the reflecting surface MS, the laser beams L1 and L1 from the laser light emitting elements LD1 and LD2 are reflected. The wavelength conversion unit WC can be irradiated with the laser beams L1 and L2 so as to make the spread angle (beam divergence angle) of L2 smaller. Further, if the profile of the curved surface is an ellipse, and the emission points of the laser beams L1 and L2 of the laser light emitting elements LD1 and LD2 are arranged at the first focal point of the ellipse, and the wavelength conversion unit WC is arranged at the second focal point of the ellipse, The laser beams L1 and L2 can be condensed on the wavelength converter WC most effectively. Further, if the profile of the mirror M is a parabola, and the emission points of the laser light emitting elements LD1 and LD2 are arranged at the focal point of the parabola, the laser beams L1 and L2 reflected by the mirror M are approximately parallel beams with a wavelength of The conversion part WC is irradiated. In this case, even if the distance D (see FIGS. 1 and 3) between the wavelength converting portion WC and the mirror portion M or the laser light emitting elements LD1 and LD2 is changed, the size of the laser spot on the wavelength converting portion WC is changed. Therefore, it is possible to easily change the design.

FIG. 20 is a vertical cross-sectional view of a light-emitting device P of a modification of Embodiment 6, taken along line XVIII-XVIII in FIG. FIG. 21 is a perspective view of the mirror portion M of the light emitting device P of the modified example of the sixth embodiment.

As shown in FIGS. 20 and 21, when a curved surface forming a convex surface with respect to the plurality of laser beams L1 and L2 is selected as the profile of the curved surface of the reflecting surface MS, the plurality of laser beams L1 and L2 emit light from the laser beams LD1 and LD2. The wavelength conversion unit WC can be irradiated with the laser beams L1 and L2 so that the divergence angles of the laser beams L1 and L2 are increased. In the present embodiment, the plurality of laser beams L1 and L2 are irradiated to the wavelength conversion unit WC in a state in which at least a portion of the plurality of laser beams L1 and L2 are superimposed. Brightness and total luminous flux can be increased. On the other hand, if the laser beams L1 and L2 are too concentrated on the wavelength conversion section WC, the wavelength conversion section WC may be damaged due to local overheating.

In the light emitting device P shown in FIGS. 20 and 21, the plurality of laser beams L1 and L2 are superimposed while increasing the spread angle (beam divergence angle) of each of the plurality of laser beams L1 and L2. As a result, while increasing the total luminous flux, the luminance is not extremely increased, or rather, the luminance can be decreased. Can be adjusted independently.

Whether the plurality of laser beams L1, L2 are more concentrated, as shown in FIG. 18, or the plurality of laser beams L1, L2 are less concentrated, as shown in FIG. It can be appropriately selected depending on factors such as the light resistance of the conversion unit WC and the heat dissipation characteristics from the wavelength conversion unit WC.

(Embodiment 7)
A light-emitting device according to Embodiment 7 will be described with reference to FIG. In the following description, the same description as in Embodiments 1 to 6 will not be repeated. The light emitting device of this embodiment differs from the light emitting devices of Embodiments 1 to 6 in the following points.

FIG. 22 is a cross-sectional view of the light emitting device P of this embodiment. As shown in FIG. 22, the mirror portion M of the light emitting device P of this embodiment has a square shape in plan view. The mirror portion M of the light emitting device P according to Embodiments 1 to 6 has an elongated rectangular shape along the Y-axis direction in plan view. does not have to be The irradiation regions of the two laser beams L1 and L2 emitted by the two laser light emitting elements LD1 and LD2 are closer than when the two laser beams are emitted in parallel. Therefore, the length of the mirror portion M in the Y-axis direction may be small. Therefore, even if the mirror portion M is square in plan view as in this embodiment, the same effect as that obtained by the light emitting device P of the above-described embodiment can be obtained. Further, by reducing the size of the mirror portion M in the Y-axis direction, the overall size of the light emitting device P can be reduced.

FIG. 23 is a cross-sectional view of a light-emitting device P of Modification 1 of the present embodiment. As shown in FIG. 23, the mirror portion M of the light-emitting device P of Modification 1 of the present embodiment has long sides extending in the X-axis direction and short sides extending in the Y-axis direction in plan view. It forms a rectangle with Even when such a mirror portion M is used, the same effect as that obtained by the light emitting device P of the above-described embodiment can be obtained, and the overall size of the light emitting device P can be reduced. .

FIG. 24 is a cross-sectional view of a light-emitting device P of Modification 2 of the present embodiment. As shown in FIG. 24, the mirror portion M of the light-emitting device P of Modification 2 of the present embodiment has a long axis extending in the X-axis direction and a short axis extending in the Y-axis direction in plan view. It has an elliptical shape with Even when such a mirror portion M is used, the same effect as that obtained by the light emitting device P of the above-described embodiment can be obtained. Furthermore, even if the mirror portion M has a circular shape in plan view instead of an elliptical shape, the same effect as that obtained by the light emitting device P of the above-described embodiment can be obtained, and the light emitting device The overall size of P can be reduced. Note that the mirror portion M may have an elliptical shape having a long axis extending in the Y-axis direction and a short axis extending in the X-axis direction in plan view.

A1L, A1R, A2L, A2R corner portion CA cap member CO concave portion E1, E2 end face L1, L2 laser light LD1, LD2 laser light emitting element M mirror portion P light emitting device S substrate SM submount W window member WC wavelength conversion member

Claims (18)

a substrate;
a plurality of submounts provided on the substrate;
a plurality of laser light emitting elements mounted on the plurality of submounts and respectively emitting a plurality of laser beams;
The light-emitting device, wherein the plurality of length directions of the plurality of laser light emitting elements respectively intersect the plurality of length directions of the plurality of submounts in plan view. 2. The light emitting device according to claim 1, wherein said plurality of laser emitting elements are mounted on said plurality of submounts in a one-to-one relationship. 3. The light emitting device according to claim 1, wherein the plurality of length directions of the plurality of submounts are parallel to each other in plan view. With respect to each of the plurality of laser light emitting elements, in plan view, one corner portion in the width direction is larger than the other corner portion in the width direction, and from the end face in the length direction of each of the plurality of submounts. The light-emitting device according to any one of claims 1 to 3, which is projected. 5. The light-emitting device according to claim 1, wherein said plurality of laser light-emitting elements are arranged mirror-symmetrically with respect to a virtual plane. 6. The light-emitting device according to claim 1, further comprising a mirror portion that reflects said plurality of laser beams. The substrate has a recess,
7. The light emitting device according to claim 6, wherein said mirror portion is provided in said concave portion. 8. The light-emitting device according to claim 6, further comprising a wavelength conversion member that converts and transmits the wavelengths of the plurality of laser beams reflected by the mirror portion. At least a portion of one of the plurality of laser beams overlaps at least a portion of another of the plurality of laser beams in the irradiation region of the plurality of laser beams on the wavelength conversion member. 9. The light emitting device according to claim 8, wherein said wavelength converting member is irradiated with said plurality of laser beams. 10. The wavelength conversion member according to claim 9, wherein the wavelength conversion member is irradiated with the plurality of laser beams such that the plurality of length directions of the plurality of irradiation regions of the plurality of laser beams on the wavelength conversion member are parallel to each other. Luminescent device. a plurality of laser light emitting elements each emitting a plurality of laser beams;
a mirror portion that reflects the plurality of laser beams;
a window member that transmits the plurality of laser beams reflected by the mirror;
a wavelength conversion member irradiated with the plurality of laser beams transmitted through the window member;
a cap member provided to cover the plurality of laser elements and the mirror portion while surrounding the window member;
The light-emitting device, wherein the cap member has a thermal conductivity higher than that of the wavelength conversion member. 12. The light emitting device according to claim 11, wherein said cap member has higher thermal conductivity than said window member. 13. The light-emitting device according to claim 11, wherein said cap member has a thermal conductivity of 50 W/(m·K) or more. The light emitting device according to any one of claims 11 to 13, wherein said cap member is made of metal, metal alloy or silicon. 15. The light-emitting device according to claim 14, wherein the metal is aluminum or copper, and the metal alloy is an aluminum alloy or a copper alloy. The light emitting device according to any one of claims 11 to 15, wherein said cap member is in contact with said wavelength conversion member. The light emitting device according to any one of claims 11 to 16, wherein the cap member is arranged so as to block the traveling of the peripheral portion of the plurality of laser beams. At least a portion of one of the plurality of laser beams overlaps at least a portion of another of the plurality of laser beams in the irradiation region of the plurality of laser beams on the wavelength conversion member. The light emitting device according to any one of claims 11 to 16, wherein the wavelength conversion member is irradiated with the plurality of laser beams such that.