JP5359817B2 - Light emitting device and projector - Google Patents

Description

  The present invention relates to a light emitting device and a projector.

  In the case of a light emitting element that emits light from both end faces of a chip, for example, the light from both ends may be flipped up by a mirror in order to direct it in the same direction. As an example of changing the direction of light using such a flip-up mirror, there is an optical communication module capable of transmitting and receiving using a light receiving and emitting element such as an optical fiber (for example, see Patent Document 1).

JP 2001-7353 A

  One of the objects according to some aspects of the present invention is to provide a light emitting device capable of highly accurately aligning a reflecting portion that reflects outgoing light. Another object of some embodiments of the present invention is to provide a projector having the light-emitting device.

The light emitting device according to the present invention is
Base and
A light emitting element that is supported by the surface of the base and emits first and second emitted light traveling in opposite directions;
A first reflecting portion that is supported on a first inner surface of a first recess formed in the base and reflects the first emitted light;
A second reflecting portion supported on the second inner surface of the second recess formed in the base and reflecting the second emitted light;
Including
The first reflecting portion is in contact with a third inner surface of the first opening connected to the first inner surface,
The second reflecting portion is in contact with a fourth inner surface of the second opening connected to the second inner surface,
The first reflected light reflected by the first reflecting portion and the second reflected light reflected by the second reflecting portion travel in the same direction.

  According to such a light emitting device, the first reflecting portion and the second reflecting portion are placed on the base so that a part thereof is pressed against the third inner surface and the fourth inner surface. Can do. That is, the third inner surface and the fourth inner surface can play a role of positioning the first reflecting portion and the second reflecting portion. Therefore, the first reflecting portion and the second reflecting portion can be easily aligned with high accuracy.

In the light emitting device according to the present invention,
The surface of the base is parallel to the traveling direction of the first outgoing light and the second outgoing light,
The first reflecting portion reflects the first emitted light on a first reflecting surface,
The second reflecting portion reflects the second emitted light on a second reflecting surface,
The first reflective surface and the second reflective surface may be inclined by 45 degrees with respect to the surface of the base.

  According to such a light emitting device, the traveling direction of the first emitted light and the traveling direction of the first reflected light can be perpendicular to each other, and the traveling direction of the second emitted light can be The traveling direction of the reflected light can be perpendicular.

In the light emitting device according to the present invention,
The first reflecting portion reflects the first emitted light on a first reflecting surface,
The second reflecting portion reflects the second emitted light on a second reflecting surface,
The first reflection surface and the second reflection surface may have a concave shape.

  According to such a light emitting device, it is possible to reflect the first emitted light and the second emitted light even when the emission angles of the first emitted light and the second emitted light are large.

In the light emitting device according to the present invention,
The first reflecting surface and the second reflecting surface have a parabolic shape,
A first emission surface of the light emitting element that emits the first emission light is located at a focal point of the first reflection surface;
The second emission surface of the light emitting element that emits the second emission light may be located at a focal point of the second reflection surface.

  According to such a light emitting device, since the first emitted light and the second emitted light can be converted into parallel light, the light use efficiency can be improved.

In the light emitting device according to the present invention,
The third inner surface is a surface that intersects with the first emitted light when viewed from a direction perpendicular to the surface of the base,
The fourth inner surface is a surface that intersects with the second emitted light when viewed from a direction perpendicular to the surface of the base,
The first inner surface and the third inner surface are connected at an obtuse angle,
The second inner surface and the fourth inner surface may be connected at an obtuse angle.

  According to such a light emitting device, there is a possibility that the first outgoing light and the second outgoing light are blocked by the surface of the base, and the shapes of the first outgoing light and the second outgoing light are distorted. It is possible to reduce the size, and it is possible to obtain outgoing light with a better shape (cross-sectional shape).

In the light emitting device according to the present invention,
The light emitting device may be a super luminescent diode.

  According to such a light emitting device, it is possible to prevent laser oscillation by suppressing the formation of a resonator due to end face reflection, and thus speckle noise can be reduced.

In the light emitting device according to the present invention,
The third inner surface is a surface that intersects with the first emitted light when viewed from a direction perpendicular to the surface of the base,
The fourth inner surface is a surface that intersects with the second emitted light when viewed from a direction perpendicular to the surface of the base,
The third inner surface and the first emission surface of the light emitting element that emits the first emitted light are in the same plane,
The fourth inner surface and the second emission surface of the light emitting element that emits the second emitted light may be in the same plane.

  According to such a light emitting device, the first outgoing light and the second outgoing light are blocked by the surface of the base, and the shapes of the first outgoing light and the second outgoing light are distorted. This can be avoided, and outgoing light having a better shape (cross-sectional shape) can be obtained.

The projector according to the present invention is
A light emitting device according to the present invention;
A light modulation device that modulates light emitted from the light emitting device according to image information;
A projection device for projecting an image formed by the light modulation device;
including.

  According to such a projector, since the light emitting device according to the present invention can be used as a light source, high reliability can be obtained.

The top view which shows typically the light-emitting device which concerns on this embodiment. FIG. 3 is a cross-sectional view schematically showing the light emitting device according to the embodiment. FIG. 3 is a cross-sectional view schematically showing the light emitting device according to the embodiment. Sectional drawing which shows typically the manufacturing process of the light-emitting device which concerns on this embodiment. Sectional drawing which shows typically the manufacturing process of the light-emitting device which concerns on this embodiment. Sectional drawing which shows typically the manufacturing process of the light-emitting device which concerns on this embodiment. Sectional drawing which shows typically the manufacturing process of the light-emitting device which concerns on this embodiment. Sectional drawing which shows typically the light-emitting device which concerns on the 1st modification of this embodiment. Sectional drawing which shows typically the light-emitting device which concerns on the 2nd modification of this embodiment. Sectional drawing which shows typically the light-emitting device which concerns on the 3rd modification of this embodiment. The top view which shows typically the light-emitting device which concerns on the 4th modification of this embodiment. Sectional drawing which shows typically the light-emitting device which concerns on the 4th modification of this embodiment. The top view which shows typically the light-emitting device which concerns on the 5th modification of this embodiment. Sectional drawing which shows typically the light-emitting device which concerns on the 5th modification of this embodiment. The top view which shows typically the light-emitting device which concerns on the 6th modification of this embodiment. Sectional drawing which shows typically the light-emitting device which concerns on the 6th modification of this embodiment. 1 is a diagram schematically showing a projector according to an embodiment.

  Preferred embodiments of the present invention will be described below with reference to the drawings.

1. First, the light emitting device 1000 according to the present embodiment will be described with reference to the drawings. FIG. 1 is a plan view schematically showing the light emitting device 1000. 2 is a cross-sectional view taken along the line II-II of FIG. 3 is a cross-sectional view taken along the line III-III of FIG. 1 and 3, the lid 180 is not shown for convenience. In FIG. 2, the light emitting element 100 is illustrated in a simplified manner for convenience.

  As shown in FIGS. 1 to 3, the light emitting device 1000 includes a package 190, a light emitting element 100, a first reflecting portion 170, a second reflecting portion 174, a submount 150, an insulating member 136, and a terminal 134. And the connection member 132. Here, a case where the light emitting element 100 is an InGaAlP-based (red) super luminescent diode (hereinafter also referred to as “SLD”) will be described. Unlike a semiconductor laser, an SLD can prevent laser oscillation by suppressing the formation of a resonator due to end face reflection. Therefore, speckle noise can be reduced.

  The light emitting element 100 is supported on the base 140 of the package 190 via the submount 150. Although not shown, the light emitting element 100 may be directly supported by the base 140 without the submount 150 interposed therebetween. It can be said that the light emitting element 100 is mounted on the base 140. As shown in FIGS. 1 to 3, the light emitting device 100 includes a clad layer (hereinafter referred to as “first clad layer”) 108, an active layer 106 formed thereon, and a clad layer ( (Hereinafter referred to as “second cladding layer”) 104. The light emitting element 100 further includes, for example, a substrate 102, a contact layer 110, an electrode (hereinafter referred to as “first electrode”) 114, an electrode (hereinafter referred to as “second electrode”) 112, and an insulating portion 116. Can have.

  As the substrate 102, for example, a first conductivity type (for example, n-type) GaAs substrate or the like can be used.

  The second cladding layer 104 is formed under the substrate 102. As the second cladding layer 104, for example, an n-type AlGaInP layer can be used. Although not shown, a buffer layer may be formed between the substrate 102 and the second cladding layer 104. As the buffer layer, for example, an n-type GaAs layer, an InGaP layer, or the like can be used.

  The active layer 106 is formed under the second cladding layer 104. The active layer 106 is provided on the base 140 side in the light emitting element 100, for example. That is, the active layer 106 is provided, for example, on the lower side of the light emitting element 100 than the middle in the thickness direction (the side opposite to the substrate 102 side). The active layer 106 is sandwiched between the second cladding layer 104 and the first cladding layer 108. The active layer 106 has, for example, a multiple quantum well (MQW) structure in which three quantum well structures each composed of an InGaP well layer and an InGaAlP barrier layer are stacked.

  The shape of the active layer 106 is, for example, a rectangular parallelepiped (including a cube). As shown in FIG. 1, the active layer 106 has a first side surface 105 and a second side surface 107. The first side surface 105 and the second side surface 107 face each other, and are parallel, for example. The active layer 106 sandwiched between the first cladding layer 108 and the second cladding layer 104 constitutes a laminated structure, for example. The first side surface 105 and the second side surface 107 are surfaces of the active layer 106 that are not in contact with the first cladding layer 108 or the second cladding layer 104, and can be said to be exposed surfaces in the stacked structure. The multilayer structure may further include a substrate 102 and a contact layer 110.

  A part of the active layer 106 constitutes a gain region 160 that becomes a current path of the active layer 106. The gain region 160 can generate light, and this light can receive gain within the gain region 160. The planar shape of the gain region 160 is, for example, a parallelogram. As shown in FIG. 1, the gain region 160 is inclined from the first side surface 105 to the second side surface 107 with respect to the normal line P of the first side surface 105 when viewed from the stacking direction of the active layer 106 (in plan view). It is provided towards. Thereby, the laser oscillation of the light generated in the gain region 160 can be suppressed or prevented. The case where the gain region 160 is provided in a certain direction means that the direction corresponds to the center of the first end surface 162 on the first side surface 105 side of the gain region 160 and the second side surface 107 in plan view. The case where it corresponds to the direction connecting the center of the second end face 164 on the side. Although one gain region 160 is provided in the illustrated example, the number thereof is not particularly limited, and a plurality of gain regions 160 may be provided.

  As shown in FIG. 3, the first cladding layer 108 is formed under the active layer 106. As the first cladding layer 108, for example, a second conductivity type (for example, p-type) AlGaInP layer or the like can be used.

  For example, the p-type first cladding layer 108, the active layer 106 not doped with impurities, and the n-type second cladding layer 104 constitute a pin diode. Each of the first cladding layer 108 and the second cladding layer 104 is a layer having a larger forbidden band width and a smaller refractive index than the active layer 106. The active layer 106 has a function of amplifying light. The first cladding layer 108 and the second cladding layer 104 have a function of confining injected carriers (electrons and holes) and light with the active layer 106 interposed therebetween.

  The contact layer 110 is formed under the first cladding layer 108. As the contact layer 110, a layer in ohmic contact with the first electrode 114 can be used. The contact layer 110 is made of, for example, a second conductivity type semiconductor. As the contact layer 110, for example, a p-type GaAs layer can be used.

The insulating part 116 is formed under the contact layer 110 other than under the gain region 160. That is, the insulating part 116 has an opening below the gain region 160, and the surface of the contact layer 110 is exposed in the opening. As the insulating part 116, for example, a SiN layer, a SiO ₂ layer, a polyimide layer, or the like can be used.

  The first electrode 114 is formed under the exposed contact layer 110 and under the insulating portion 116. The first electrode 114 is electrically connected to the first cladding layer 108 via the contact layer 110. The first electrode 114 is one electrode for driving the light emitting element 100. As the first electrode 114, for example, a layer in which a Cr layer, an AuZn layer, and an Au layer are stacked in this order from the contact layer 110 side can be used. The contact surface between the first electrode 114 and the contact layer 110 has, for example, the same planar shape as that of the gain region 160. In the illustrated example, the current path between the electrodes 112 and 114 is determined by the planar shape of the contact surface between the first electrode 114 and the contact layer 110, and as a result, the planar shape of the gain region 160 can be determined. .

  The second electrode 112 is formed on the entire surface of the substrate 102. The second electrode 112 can be in contact with a layer that is in ohmic contact with the second electrode 112 (the substrate 102 in the illustrated example). The second electrode 112 is electrically connected to the second cladding layer 104 via the substrate 102. The second electrode 112 is the other electrode for driving the light emitting element 100. As the second electrode 112, for example, a layer in which a Cr layer, an AuGe layer, a Ni layer, and an Au layer are stacked in this order from the substrate 102 side can be used. A second contact layer (not shown) is provided between the second clad layer 104 and the substrate 102, and the second electrode layer is exposed by dry etching or the like to expose the second electrode. 112 may be provided under the second contact layer. Thereby, a single-sided electrode structure can be obtained. For example, an n-type GaAs layer can be used as the second contact layer.

  In the light emitting element 100, when a forward bias voltage of a pin diode is applied between the first electrode 114 and the second electrode 112, recombination of electrons and holes occurs in the gain region 160 of the active layer 106. This recombination causes light emission. Starting from this generated light, stimulated emission occurs in a chain, the light travels in the gain region 160, and the light intensity is amplified during that time, and the first outgoing light L1 is emitted from the first end face (first outgoing face) 170. And can be emitted from the second end face (second emission surface) 172 as the second emission light L2. The first emitted light L1 and the second emitted light L2 can be emitted in a direction more inclined than the inclination of the gain region 160 with respect to the perpendicular P of the first side surface 107, for example, due to light refraction. The first outgoing light L1 and the second outgoing light L2 can travel in a direction parallel to the upper surface of the active layer 106 (a direction parallel to the surface 141 of the base 140), for example. The traveling direction of the first emitted light L1 and the traveling direction of the second emitted light L2 are opposite to each other.

  The package 190 can have a base 140 and a lid 180. The surface 141 of the base 140 can indirectly support the light emitting device 100 through the submount 150. Examples of the material of the base 140 include Cu, Al, Mo, W, Si, C, Be, Au, and these compounds (for example, AlN, BeO) and alloys (for example, CuMo). . Further, the base 140 can also be configured from a combination of these examples, for example, a multilayer structure of a copper (Cu) layer and a molybdenum (Mo) layer. As the base 140, for example, a plate-shaped (cuboid) member provided with an opening 149 can be used. It can be said that the surface 141 of the base 140 is the bottom surface of the opening 149. A first recess 142 and a second recess 145 are formed on the surface 141 side of the base 140.

  As shown in FIG. 2, the first recess 142 has at least a first inner surface 143 and a third inner surface 144. It can be said that at least the first inner surface 143 and the third inner surface 144 define the first recess 142. It can be said that the first inner surface 143 is a surface forming the bottom surface of the first recess 142. The third inner surface 144 is connected to the first inner surface 143. In the illustrated example, the first inner surface 143 and the third inner surface 144 are connected at a right angle. It can be said that the third inner surface 144 is a surface forming the side surface of the first recess 142. The planar shape of the first recess 142 is rectangular in the example illustrated in FIG. 1, but is not particularly limited.

  The second recess 145 has at least a second inner surface 146 and a fourth inner surface 147. It can be said that at least the second inner surface 146 and the fourth inner surface 147 define the second recess 145. It can be said that the second inner surface 146 forms a bottom surface of the second recess 145. The fourth inner surface 147 is connected to the second inner surface 146. In the illustrated example, the second inner surface 146 and the fourth inner surface 147 are connected at a right angle. It can be said that the fourth inner surface 147 is a surface forming the side surface of the second recess 145. The planar shape of the second recess 145 is rectangular in the example shown in FIG. 1, but is not particularly limited.

  The first reflecting portion 170 is supported on the first inner surface 143 of the first recess 142. In the illustrated example, the first reflecting portion 170 is in contact with the first inner surface 143. The first reflecting portion 170 is further in contact with the third inner surface 144. That is, the first reflecting portion 170 is in contact with at least one surface (third inner surface 144) among the surfaces forming the side surfaces of the first recess 142. It can be said that the first reflecting portion 170 is fixed by the first inner surface 143 and the third inner surface 144. In the illustrated example, the third inner surface 144 with which the first reflecting portion 170 contacts is the surface on the light emitting element 100 side of the surfaces forming the side surfaces of the first recess 142, but the third inner surface 144 is the first recess 142. Any surface may be used. As shown in FIG. 1, the first reflecting portion 170 may be in contact with all the surfaces of the surfaces forming the side surfaces of the first recess 142. That is, the planar shape of the first reflecting portion 170 and the planar shape of the first recess 142 may be the same.

  As shown in FIGS. 1 and 2, the first reflecting unit 170 can reflect the first outgoing light L <b> 1 at the first reflecting surface 172. It can be said that the first reflecting surface 172 is a surface on the surface of the first reflecting portion 170 on which the first outgoing light L1 is incident. As shown in FIG. 2, the first reflecting surface 172 can reflect the first emitted light L <b> 1 toward the upper side of the light emitting element 100. The first emitted light L1 is reflected by the first reflecting surface 172, and can travel, for example, vertically upward (Z direction in FIG. 1) with respect to the upper surface of the active layer 106 as the first reflected light L3. The first reflecting surface 172 is inclined with respect to the surface 141 of the base 140, and is inclined 45 degrees in the illustrated example. Thereby, the direction in which the first emitted light L1 travels can be perpendicular to the direction in which the first reflected light L3 travels. The reflectance of the first reflecting surface 172 with respect to the first outgoing light L1 is preferably higher than 50% and not higher than 100%. Examples of the material of the first reflection unit 170 include Al, Ag, Au, and the like. For example, only the material of the surface of the first reflection unit 170 may be the above material (for example, Al, Ag, Au), so that the surface of the first reflection unit 170 may be the first reflection surface 172.

  The second reflecting portion 174 is supported by the second inner surface 146 of the second recess 145. In the illustrated example, the second reflecting portion 174 is in contact with the second inner surface 146. The second reflecting portion 174 is further in contact with the fourth inner surface 147. In other words, the second reflecting portion 174 is in contact with at least one surface (fourth inner surface 147) among the surfaces forming the side surfaces of the second recess 145. It can be said that the second reflecting portion 174 is fixed by the second inner surface 146 and the fourth inner surface 147. In the illustrated example, the fourth inner surface 147 with which the second reflecting portion 174 contacts is the surface on the light emitting element 100 side among the surfaces forming the side surfaces of the second recess 145, but the fourth inner surface 147 is the second recess 145. Any surface may be used. As shown in FIG. 1, the second reflecting portion 174 may also be in contact with all surfaces among the surfaces forming the side surfaces of the second recess 145. That is, the planar shape of the second reflecting portion 174 and the planar shape of the second recess 145 may be the same.

  As shown in FIGS. 1 and 2, the second reflecting portion 174 can reflect the second emitted light L <b> 2 at the second reflecting surface 176. It can be said that the second reflecting surface 176 is a surface on the surface of the second reflecting portion 174 on which the second outgoing light L2 is incident. As shown in FIG. 2, the second reflecting surface 176 can reflect the second emitted light L <b> 2 toward the upper side of the light emitting element 100. The second emitted light L2 is reflected by the second reflecting surface 176, and can travel, for example, vertically upward (Z direction in FIG. 1) with respect to the upper surface of the active layer 106 as the second reflected light L4. The second reflecting surface 176 is inclined with respect to the surface 141 of the base 140, and is inclined 45 degrees in the illustrated example. Thereby, the advancing direction of the 2nd emitted light L2 and the advancing direction of the 2nd reflected light L4 can make a right angle. The reflectance of the second reflecting surface 176 with respect to the second outgoing light L2 is preferably higher than 50% and not higher than 100%. Examples of the material of the second reflecting portion 174 include Al, Ag, Au, and the like. For example, the surface of the second reflecting portion 174 may be the second reflecting surface 176 by using only the material of the surface of the second reflecting portion 174 as the material (for example, Al, Ag, Au).

  As shown in FIG. 1, the traveling direction of the first outgoing light L <b> 1 is perpendicular to the intersecting line V between the surface (XY plane) parallel to the upper surface of the active layer 106 and the first reflecting surface 172. Yes. Similarly, the traveling direction of the second outgoing light L2 is perpendicular to the intersection line W between the surface parallel to the upper surface of the active layer 106 and the second reflecting surface 176. Thereby, the traveling direction of the first reflected light L3 by the first reflecting surface 172 and the traveling direction of the second reflected light L4 by the second reflecting surface 176 can be made the same.

  The submount 150 is supported on the surface 141 of the base 140. As the submount 150, for example, a plate-like member can be used. The submount 150 can directly support the light emitting element 100. For example, the thermal conductivity of the submount 150 is larger than the thermal conductivity of the light emitting element 100 and smaller than the thermal conductivity of the base 140. The thermal conductivity of each of the base 140 and the submount 150 is, for example, 140 W / mK or more. Examples of the material of the submount 150 include AlN, CuW, SiC, BeO, CuMo, CMC in which Cu and Mo are stacked, and the like. The submount 150 can prevent warpage of the light emitting element 100 caused by a difference in thermal expansion coefficient between the base 140 and the light emitting element 100.

  As shown in FIGS. 1 and 3, for example, a cylindrical through hole 137 is formed in the base 140. In the through hole 137, for example, a columnar terminal 134 whose side surface is covered with an insulating member 136 is provided. The insulating member 136 is made of, for example, resin, ceramics (for example, AlN). The terminal 134 is made of, for example, copper (Cu).

  The terminal 134 is connected to the second electrode 112 of the light emitting element 100 by a connection member 132 such as wire bonding. The connecting member 132 is provided so as not to block the optical paths of the emitted lights L1 and L2. Further, the first electrode 114 of the light emitting element 100 is connected to the submount 150 by, for example, a plating bump or the like (not shown). The submount 150 is connected to the base 140 by, for example, solder or silver paste. A voltage can be applied between the first electrode 114 and the second electrode 112 by applying different potentials to the terminal 134 and the base 140.

  The lid 180 is provided on the base 140 as shown in FIG. The lid 180 can seal the light emitting element 100 provided in the recess 149 by sealing the recess 149 of the base 140. The lid 180 is made of a material that is transparent to the wavelengths of the reflected lights L3 and L4. Thereby, at least a part of the first reflected light L3 can pass through the lid 180, and at least a part of the second reflected light L4 can pass through the lid 180. The lid 180 can be made of, for example, quartz, glass, quartz, plastic, or the like. These can be appropriately selected according to the wavelengths of the reflected lights L3 and L4. Thereby, the absorption loss of light can be reduced.

  As an example of the light-emitting device 1000, the case where the light-emitting element 100 is an InGaAlP system has been described, but the light-emitting element 100 can use any material system capable of forming a light-emitting gain region. As the semiconductor material, for example, an AlGaN-based, InGaN-based, GaAs-based, InGaAs-based, GaInNAs-based, or ZnCdSe-based semiconductor material can be used.

  The light emitting device 1000 has the following features, for example.

  According to the light emitting device 1000, the first reflecting portion 170 can be supported by the first inner surface 143 of the first recess 142 and can be in contact with the third inner surface 144. Similarly, the second reflecting portion 174 can be supported by the second inner surface 146 of the second recess 145 and in contact with the fourth inner surface 147. That is, the reflecting portions 170 and 174 are placed on the base 140 such that a part thereof is pressed against the inner surfaces 144 and 147. That is, the inner surfaces 144 and 147 can play a role of positioning the reflecting portions 170 and 174. Therefore, in the light emitting device 1000, the reflecting portions 170 and 174 can be easily aligned with high accuracy.

  According to the light emitting device 1000, the first reflecting portion 170 can be in contact with all of the inner surface of the first recess 142, and the second reflecting portion 172 can be in contact with all of the inner surface of the second recess 145. That is, the planar shape of the first reflecting portion 170 and the planar shape of the first recess 142 are the same, and the planar shape of the second reflecting portion 174 and the planar shape of the second recess 145 can be the same. . Thereby, in the light-emitting device 100, the reflection parts 170 and 174 can be supported stably. In the light emitting device 100, for example, even when an impact is applied to the light emitting device 100 from the outside, it is possible to prevent the positions of the reflecting portions 170 and 174 from shifting.

  According to the light emitting device 1000, the two outgoing lights L1 and L2 can be reflected in the same direction. That is, the traveling direction of the first reflected light L3 by the first reflecting unit 170 and the traveling direction of the second reflected light L4 by the second reflecting unit 174 can be made the same. Thereby, for example, when the light-emitting device 1000 is used as a light source of a projector, the configuration of the optical system of the projector can be simplified, and optical axis alignment can be facilitated in the projector.

  According to the light emitting device 1000, the light emitting element 100 can be an SLD. Therefore, it is possible to suppress or prevent laser oscillation of light generated in the gain region 160. Therefore, speckle noise can be reduced.

  According to the light emitting device 1000, the active layer 106 can be provided on the base 140 side in the light emitting element 100. That is, the active layer 106 is provided on the light emitting element 100 below the middle in the thickness direction (on the side opposite to the substrate 102 side). Further, the thermal conductivity of the base 140 is larger than the thermal conductivity of the light emitting device 100. Therefore, the heat dissipation of the light emitting element 100 can be improved.

2. Method for Manufacturing Light-Emitting Device Next, a method for manufacturing the light-emitting device 1000 according to the present embodiment will be described with reference to the drawings. 4 to 7 are cross-sectional views schematically showing the manufacturing process of the light emitting device 1000.

  As shown in FIG. 4, the second cladding layer 104, the active layer 106, the first cladding layer 108, and the contact layer 110 are epitaxially grown in this order on the substrate 102. As a method for epitaxial growth, for example, MOCVD (Metal Organic Chemical Vapor Deposition) method, MBE (Molecular Beam Epitaxy) method or the like can be used.

  As shown in FIG. 5, an insulating part 116 having an opening is formed on the contact layer 110. The insulating part 116 is formed by, for example, a CVD (Chemical Vapor Deposition) method. The opening is formed, for example, by patterning the insulating portion by photolithography technique and etching technique so that the contact layer 110 is exposed.

  Next, the first electrode 114 is formed on the exposed contact layer 110 and the insulating portion 116. Next, the second electrode 112 is formed under the lower surface of the substrate 102. The first electrode 114 and the second electrode 112 are formed by, for example, a vacuum evaporation method. Note that the order of forming the first electrode 114 and the second electrode 112 is not particularly limited. Through the above steps, the light-emitting element 100 can be obtained.

  As shown in FIG. 6, the base 140 having the first concave portion 142 and the second concave portion 145 is produced by, for example, cutting.

  As shown in FIG. 7, a through hole 137 is provided in the base 140 by a known method. Next, the insulating member 136 is formed so as to cover the inner side surface of the through hole 137. The insulating member 136 is formed so as not to block the through hole 137. The insulating member 136 is formed by, for example, a CVD method. Next, the rod-shaped terminal 134 is inserted inside the insulating member 136. Note that a method in which an insulating member 136 formed around the rod-shaped terminal 134 is inserted into the through hole 137 can also be used.

  As shown in FIG. 3, the submount 150 on which the light emitting element 100 is mounted is mounted on the base 140. The submount 150 is mounted by, for example, solder. Note that only the submount 150 may be mounted on the base 140 first, and then the light emitting element 100 may be mounted on the submount 150. The light emitting element 100 is mounted with the active layer 106 side facing the base 140 side (junction down). That is, the light emitting element 100 can be flip-chip mounted.

  As shown in FIGS. 1 and 2, the first reflecting portion 170 is placed on the first inner surface 143 so as to be pressed against the third inner surface 144. Similarly, the second reflecting portion 174 is placed on the third inner surface 146 so as to be pressed against the fourth inner surface 147. The reflecting portions 170 and 174 may be fixed to the concave portions 142 and 145 through an adhesive. The reflective portions 170 and 174 may be formed so that the surfaces thereof become the reflective surfaces 172 and 176, for example, by vapor deposition.

  As shown in FIG. 3, the terminal 134 and the second electrode 112 of the light emitting element 100 are connected by a connecting member 132. This step is performed, for example, by wire bonding. In addition, the process of connecting the terminal 134 and the 2nd electrode 112 and the process of mounting the reflection parts 170 and 174 do not ask before and after.

  As shown in FIG. 2, the lid 180 is bonded or welded to the base 140 in, for example, a nitrogen atmosphere. Thereby, the light emitting element 100 can be sealed.

  Through the above steps, the light-emitting device 1000 can be manufactured.

  According to the method for manufacturing the light emitting device 1000, the reflecting portions 170 and 174 can be easily aligned with high accuracy.

3. Next, light-emitting devices 2000, 3000, 4000, 5000, 6000, and 7000 according to variations of the present embodiment will be described with reference to the drawings. Hereinafter, in the light emitting devices 2000, 3000, 4000, 5000, 6000, and 7000 according to the modification of the present embodiment, members having the same functions as the constituent members of the light emitting device 1000 according to the present embodiment are denoted by the same reference numerals. Detailed description thereof will be omitted.

(1) Light-Emitting Device According to First Modification First, a light-emitting device 2000 according to a first modification of the present embodiment will be described with reference to the drawings. FIG. 8 is a cross-sectional view schematically showing the light emitting device 2000, and corresponds to FIG. In FIG. 8, the light-emitting element 100 is simplified for convenience.

  In the example of the light emitting device 1000, as illustrated in FIG. 2, the first reflecting surface 172 and the second reflecting surface 176 are inclined 45 degrees with respect to the surface 141 of the base 140. On the other hand, in the light emitting device 2000, the first reflection surface 172 and the second reflection surface 176 can be concave. That is, the first reflecting surface 172 and the second reflecting surface 176 can be concave mirrors. According to the light emitting device 2000, both the outgoing lights L1 and L2 can be reflected toward the upper side of the light emitting element 100 even when the emission angles of the outgoing lights L1 and L2 are large.

  Further, in the illustrated example, the first reflecting surface 172 and the second reflecting surface 176 have a parabolic shape. That is, the first reflecting surface 172 and the second reflecting surface 176 can be parabolic mirrors. For example, the first end surface 162 (first emission surface) of the light emitting element 100 is disposed so as to be located at the focal point of the first reflection surface 172, and the second end surface 164 (second emission surface) of the light emitting element 100 is, for example, The second reflection 176 is disposed at the focal point. Thereby, the two emitted lights L1 and L2 emitted from the light emitting element 100 in the direction parallel to the surface 141 of the base 140 can be reflected in the same direction and can be converted into parallel lights. Thus, according to the light-emitting device 2000, since the emitted lights L1 and L2 can be further converted into parallel light, the light utilization efficiency can be improved.

(2) Light Emitting Device According to Second Modification Next, a light emitting device 3000 according to a second modification of the present embodiment will be described with reference to the drawings. FIG. 9 is a sectional view schematically showing the light emitting device 3000 and corresponds to FIG. In FIG. 9, the lid 180 is not shown for convenience.

  In the example of the light emitting device 1000, as shown in FIG. 3, the active layer 106 is provided on the base 140 side in the light emitting element 100. On the other hand, in the light emitting device 3000, as shown in FIG. 9, the active layer 106 is provided on the side opposite to the base 140 in the light emitting element 100. That is, the active layer 106 is provided above the middle of the light emitting element 100 in the thickness direction. In the light emitting device 3000, the substrate 102 is provided between the active layer 106 and the base 140. The second electrode 112 is connected to the submount 150 by, for example, a connection member (not shown). The first electrode 114 is connected to the terminal 134 by, for example, a connection member 132.

  According to the light emitting device 3000, since the substrate 102 is provided between the active layer 106 and the base 140, the active layer 106 is separated from the base 140 by at least the thickness of the substrate 102 compared to the example of the light emitting device 1000. It is provided at the position. Therefore, it is possible to obtain outgoing light having a better shape (cross-sectional shape). For example, if the emission angles of the outgoing lights L1 and L2 from the gain region 160 are large, the outgoing lights L1 and L2 may be blocked by the base 140 (surface 141), and the shapes of the outgoing lights L1 and L2 may be distorted. In the light emitting device 3000, such a problem can be avoided.

(3) Light Emitting Device According to Third Modification Next, a light emitting device 4000 according to a third modification of the present embodiment will be described with reference to the drawings. FIG. 10 is a cross-sectional view schematically showing the light emitting device 4000, and corresponds to FIG. In addition, in FIG. 10, illustration of the lid 180 is abbreviate | omitted for convenience.

  In the example of the light emitting device 1000, the so-called gain waveguide type has been described. On the other hand, the light emitting device 4000 can be a so-called refractive index waveguide type.

  That is, in the light emitting device 4000, as shown in FIG. 10, the contact layer 110 and a part of the first cladding layer 108 can form a columnar portion 111. The planar shape of the columnar portion 111 is the same as that of the gain region 160. For example, the current path between the electrodes 112 and 114 is determined by the planar shape of the columnar portion 111, and as a result, the planar shape of the gain region 160 is determined. Although not shown, the columnar portion 111 may be composed of, for example, the contact layer 110, the first cladding layer 108, and the active layer 106, and further includes the second cladding layer 104. It may be. Moreover, the side surface of the columnar part 111 can also be inclined.

  An insulating part 116 is provided on the side of the columnar part 111. The insulating part 116 can be in contact with the side surface of the columnar part 111. The current between the electrodes 112 and 114 can flow through the columnar portion 111 sandwiched between the insulating portions 116, avoiding the insulating portions 116. The insulating part 116 may have a refractive index smaller than that of the active layer 106. Thereby, light can be efficiently confined in the gain region 160 in the planar direction (direction parallel to the upper surface of the active layer 106).

(4) Light Emitting Device According to Fourth Modification Next, a light emitting device 5000 according to a fourth modification of the present embodiment will be described with reference to the drawings. FIG. 11 is a plan view schematically showing the light emitting device 5000. 12 is a cross-sectional view taken along line XII-XII of FIG. 11 schematically showing the light emitting device 5000. In FIG. 11, the lid 180 is not shown for convenience. In FIG. 12, the light-emitting element 100 is simplified for convenience.

  In the example of the light emitting device 1000, as shown in FIG. 2, the first inner surface 143 and the third inner surface 144 are connected at a right angle, and the second inner surface 146 and the fourth inner surface 147 are connected at a right angle. It had been. On the other hand, in the light emitting device 5000, as shown in FIG. 12, the first inner surface 143 and the third inner surface 144 are connected at an obtuse angle θ1. Similarly, the second inner surface 146 and the fourth inner surface 147 are connected at an obtuse angle θ2. In the illustrated example, the obtuse angles θ1 and θ2 are 135 degrees.

  In the light emitting device 5000, the third inner surface 144 is a surface that intersects with the first outgoing light L1 when viewed from the normal direction of the surface 141 of the base 140 (in plan view) as shown in FIG. For example, it can be said that the third inner surface 144 is a surface on the light emitting element 100 side among the surfaces forming the side surfaces of the first recess 142. Similarly, the fourth inner surface 147 is a surface that intersects the second emitted light L2 in plan view. For example, the fourth inner surface 147 can be said to be a surface on the light emitting element 100 side among the surfaces forming the side surfaces of the second recess 145.

  According to the light emitting device 5000, the first inner surface 143 and the third inner surface 144 are connected at an obtuse angle θ1, and the second inner surface 146 and the fourth inner surface 147 are connected at an obtuse angle θ2. Therefore, compared with the example of the light emitting device 1000, for example, the possibility that the outgoing lights L1 and L2 are blocked by the surface 141 and the shapes of the outgoing lights L1 and L2 are distorted can be reduced, and a better shape (cross section) Shape) emission light can be obtained.

(5) Light-Emitting Device According to Fifth Modification Next, a light-emitting device 6000 according to a fifth modification of the present embodiment will be described with reference to the drawings. FIG. 13 is a plan view schematically showing the light emitting device 6000. 14 is a cross-sectional view taken along line XIV-XIV in FIG. 13 schematically showing the light emitting device 6000. As shown in FIG. In FIG. 13, the lid 180 is not shown for convenience. In FIG. 14, the light emitting element 100 is illustrated in a simplified manner for convenience.

  In the example of the light emitting device 1000, as shown in FIGS. 1 and 2, one light emitting element 100 is provided in the package 190. On the other hand, in the light emitting device 6000, a plurality of the light emitting elements 100 can be provided in the package 190 as shown in FIGS. In the illustrated example, two light emitting elements 100 are provided, but the number is not particularly limited.

  In the illustrated example, in the adjacent light emitting elements 100 (100a, 100b), the second reflecting portion 174 of one light emitting element 100a and the first reflecting portion 170 of the other light emitting element 100b are used as a common member. Can do. That is, the common reflecting portion has a second reflecting surface 176 that reflects the emitted light L2 of one light emitting element 100a and a first reflecting surface 172 that reflects the emitted light L1 of the other light emitting element 100b. Can do. Similarly, the second recess 145 of one light emitting element 100a and the first recess 142 of the other light emitting element 100b can be used as a common recess. Thereby, the light emitting device can be reduced in size accordingly.

  According to the light emitting device 6000, for example, compared to the example of the light emitting device 1000, the output of the entire light emitting device can be increased.

(6) Light Emitting Device According to Sixth Modification Next, a light emitting device 7000 according to a sixth modification of the present embodiment will be described with reference to the drawings. FIG. 15 is a plan view schematically showing the light emitting device 7000. 16 is a cross-sectional view taken along the line XVI-XVI of FIG. In FIG. 15, the lid 180 is not shown for convenience. In FIG. 16, the light-emitting element 100 is simplified for convenience.

  In the example of the light emitting device 1000, the case where the light emitting element 100 is an SLD has been described. On the other hand, in the light emitting device 7000, the light emitting element 100 can be a semiconductor laser.

  That is, in the light emitting device 7000, as shown in FIG. 15, the gain region 160 of the light emitting element 100 is provided orthogonal to the first side surface 105 and the second side surface 107. That is, the gain region 160 is provided in a direction parallel to the normal line P of the first side surface 105. Therefore, a resonator can be formed between the first end surface 162 and the second end surface 164. Further, the emitted lights L1 and L2 can travel in a direction orthogonal to the side surfaces 105 and 107.

  In the light emitting device 7000, the third inner surface 144 is a surface that intersects the first emitted light L1 in a plan view as shown in FIG. For example, it can be said that the third inner surface 144 is a surface on the light emitting element 100 side among the surfaces forming the side surfaces of the first recess 142. Similarly, the fourth inner surface 147 is a surface that intersects the second emitted light L2 in plan view. For example, the fourth inner surface 147 can be said to be a surface on the light emitting element 100 side among the surfaces forming the side surfaces of the second recess 145.

  In the light emitting device 7000, as shown in FIGS. 15 and 16, the first end surface 162, the third side surface 152 on the first end surface 162 side of the submount 150, and the third inner surface 144 are in the same plane. Similarly, the second end surface 164, the fourth side surface 154 on the second end surface 164 side of the submount 150, and the fourth inner surface 147 are in the same plane. That is, in the light emitting device 7000, the light emitting element 100 and the first reflecting unit 170 are in contact with each other in plan view, and the surface of the base 140 is not exposed between the light emitting element 100 and the first reflecting unit 170. Similarly, the light emitting element 100 and the second reflecting portion 174 are in contact with each other, and the surface of the base 140 is not exposed between the light emitting element 100 and the second reflecting portion 174. Thereby, in the light-emitting device 7000, it is possible to obtain emitted light having a better shape (cross-sectional shape). For example, if the emission angle of the emitted light from the gain region 160 is large, the emitted light may be blocked by the base 140, and the shape of the emitted light may be distorted. In the light emitting device 7000, such a problem can be avoided.

4). Projector Next, a projector 8000 according to this embodiment will be described with reference to the drawings. FIG. 17 is a diagram schematically showing the projector 8000. In FIG. 17, for convenience, the casing that configures the projector 8000 is omitted.

  In the projector 8000, a red light source (light emitting device) 1000R that emits red light, green light, and blue light, a green light source (light emitting device) 1000G, and a blue light source (light emitting device) 1000B are light emitting devices (for example, light emitting devices) according to the present invention. 1000).

  The projector 8000 includes transmissive liquid crystal light valves (light modulation devices) 804R, 804G, and 804B that modulate light emitted from the light sources 1000R, 1000G, and 1000B in accordance with image information, and liquid crystal light valves 804R, 804G, and 804B. A projection lens (projection device) 808 that magnifies and projects the image formed on the screen (display surface) 810. In addition, the projector 8000 can include a cross dichroic prism (color light combining unit) 806 that combines light emitted from the liquid crystal light valves 804R, 804G, and 804B and guides the light to the projection lens 808.

  Further, the projector 8000 has uniformizing optical systems 802R, 802G, and 802B disposed downstream of the light sources 1000R, 1000G, and 1000B in order to uniformize the illuminance distribution of the light emitted from the light sources 1000R, 1000G, and 1000B. The liquid crystal light valves 804R, 804G, and 804B are illuminated with light that has been provided with uniform illumination distribution. The uniformizing optical systems 802R, 802G, and 802B include, for example, a hologram 802a and a field lens 802b.

  The three color lights modulated by the liquid crystal light valves 804R, 804G, and 804B are incident on the cross dichroic prism 806. This prism is formed by bonding four right-angle prisms, and a dielectric multilayer film that reflects red light and a dielectric multilayer film that reflects blue light are arranged in a cross shape on the inner surface thereof. These dielectric multilayer films combine the three color lights to form light representing a color image. The synthesized light is projected onto the screen 810 by the projection lens 806, which is a projection optical system, and an enlarged image is displayed.

  According to the projector 8000, as described above, the light-emitting device 1000 that can perform the alignment of the reflection units 170 and 174 with high accuracy can be used as the light source. Therefore, the projector 8000 can have high reliability.

  In the above example, a transmissive liquid crystal light valve is used as the light modulation device. However, a light valve other than liquid crystal may be used, or a reflective light valve may be used. Examples of such a light valve include a reflective liquid crystal light valve and a digital micromirror device. Further, the configuration of the projection optical system is appropriately changed depending on the type of light valve used.

  Further, the light-emitting device 1000 has a scanning unit that is a scanning unit that is an image forming device that displays an image of a desired size on a display surface by scanning light from the light-emitting device 1000 on a screen. The present invention can also be applied to a light source device of a device (projector).

  In addition, embodiment mentioned above and a modification are examples, Comprising: It is not necessarily limited to these. For example, it is possible to appropriately combine each embodiment and each modification.

  Although the embodiments of the present invention have been described in detail as described above, those skilled in the art will readily understand that many modifications are possible without substantially departing from the novel matters and effects of the present invention. Accordingly, all such modifications are intended to be included in the scope of the present invention.

100 light emitting element, 102 substrate, 104 second cladding layer, 105 first side surface,
106 active layer, 107 second side surface, 108 first cladding layer, 110 contact layer,
111 columnar section, 112 second electrode, 114 first electrode, 116 insulating section,
132 connecting members, 134 terminals, 136 insulating members, 137 through holes,
140 base, 141 surface, 142 first recess, 143 first inner surface,
144 third inner surface, 145 second recess, 146 second inner surface, 147 fourth inner surface,
149 opening, 150 submount, 152 third side, 154 fourth side,
160 gain region, 162 first end face, 164 second end face, 170 first reflecting portion,
172 1st reflection surface, 174 2nd reflection part, 176 2nd reflection surface, 180 lid,
190 package, 802 homogenizing optical system, 802a hologram,
802b field lens, 804 liquid crystal light valve,
806 Cross dichroic prism, 808 projection lens, 810 screen,
1000 to 7000 Light emitting device, 8000 projector

Claims (8)

Base and
A light emitting element that is supported by the surface of the base and emits first and second emitted light traveling in opposite directions;
A first reflecting portion that is supported on a first inner surface of a first recess formed in the base and reflects the first emitted light;
A second reflecting portion supported on the second inner surface of the second recess formed in the base and reflecting the second emitted light;
Including
The first reflecting portion is in contact with a third inner surface of the first recess connected to the first inner surface,
The second reflecting portion is in contact with a fourth inner surface of the second recess connected to the second inner surface,
The first reflected light reflected by the first reflecting unit and the second reflected light reflected by the second reflecting unit travel in the same direction. In claim 1,
The surface of the base is parallel to the traveling direction of the first outgoing light and the second outgoing light,
The first reflecting portion reflects the first emitted light on a first reflecting surface,
The second reflecting portion reflects the second emitted light on a second reflecting surface,
The light emitting device, wherein the first reflecting surface and the second reflecting surface are inclined by 45 degrees with respect to the surface of the base. In claim 1,
The first reflecting portion reflects the first emitted light on a first reflecting surface,
The second reflecting portion reflects the second emitted light on a second reflecting surface,
The light emitting device, wherein the first reflecting surface and the second reflecting surface have a concave shape. In claim 3,
The first reflecting surface and the second reflecting surface have a parabolic shape,
A first emission surface of the light emitting element that emits the first emission light is located at a focal point of the first reflection surface;
The light emitting device, wherein a second emission surface of the light emitting element that emits the second emission light is located at a focal point of the second reflection surface. In any one of Claims 1 thru | or 4,
The third inner surface is a surface intersecting with the first emitted light in a plan view ,
The fourth inner surface is a surface intersecting with the second emitted light in a plan view ,
The first inner surface and the third inner surface are connected at an obtuse angle,
The light emitting device, wherein the second inner surface and the fourth inner surface are connected at an obtuse angle. In any one of Claims 1 thru | or 5,
The light-emitting device is a superluminescent diode. In any one of Claims 1 thru | or 4,
The third inner surface is a surface intersecting with the first emitted light in a plan view ,
The fourth inner surface is a surface intersecting with the second emitted light in a plan view ,
The third inner surface and the first emission surface of the light emitting element that emits the first emitted light are in the same plane,
The light emitting device, wherein the fourth inner surface and the second emission surface of the light emitting element that emits the second emitted light are in the same plane. A light emitting device according to any one of claims 1 to 7,
A light modulation device that modulates light emitted from the light emitting device according to image information;
A projection device for projecting an image formed by the light modulation device;
Including projector.

Images