阅读说明：本技术 发光装置和投影仪 (Light emitting device and projector ) 是由 西冈大毅 岸野克巳 于 2019-08-01 设计创作，主要内容包括：提供发光装置和投影仪,该发光装置射出的光是直线偏振光。发光装置具有：基体；以及层叠体,其设置于所述基体,具有由p个柱状部构成的柱状部集合体,所述层叠体具有多个所述柱状部集合体,所述p个柱状部分别具有发光层,在从所述层叠体的层叠方向观察时,由所述多个柱状部各自的中心构成的图形是旋转对称的,所述p个柱状部中的q个柱状部的径与所述p个柱状部中的r个柱状部的径不同,所述柱状部集合体的形状不是旋转对称的,所述p是2以上的整数,所述q是1以上且小于p的整数,所述r是满足r＝p-q的整数。(Provided are a light-emitting device and a projector, wherein light emitted by the light-emitting device is linearly polarized light. The light emitting device includes: a substrate; and a laminate provided on the substrate, the laminate having a columnar portion aggregate made up of p columnar portions, the laminate having a plurality of the columnar portion aggregates, the p columnar portions each having a light-emitting layer, a pattern formed by the centers of the plurality of columnar portions being rotationally symmetric when viewed from the lamination direction of the laminate, the diameter of q columnar portions of the p columnar portions being different from the diameter of r columnar portions of the p columnar portions, the columnar portion aggregate not being rotationally symmetric in shape, p being an integer of 2 or more, q being an integer of 1 or more and less than p, and r being an integer satisfying r-p-q.)

1. A light emitting device, comprising:

a substrate; and

a laminate provided on the base and having a columnar portion aggregate consisting of p columnar portions,

the laminate body has a plurality of the columnar portion aggregate,

the p columnar portions each have a light-emitting layer,

a pattern constituted by the centers of the p columnar portions is rotationally symmetric when viewed from the stacking direction of the stacked body,

the diameter of q of the p columnar portions is different from the diameter of r of the p columnar portions,

the shape of the columnar part aggregate is not rotationally symmetrical,

wherein p is an integer of 2 or more,

q is an integer of 1 or more and less than p,

and r is an integer satisfying r ═ p-q.

2. A light emitting device, comprising:

a substrate; and

a laminate provided on the base and having a columnar portion aggregate consisting of p columnar portions,

the laminate body has a plurality of the columnar portion aggregate,

the p columnar portions each have a light-emitting layer,

when the p lattice points that are rotationally symmetric are defined on the base when viewed from the stacking direction of the laminate, the centers of q columnar portions of the p columnar portions are arranged at the lattice points, and the centers of r columnar portions of the p columnar portions are arranged at positions different from the lattice points,

the shape of the columnar part aggregate is not rotationally symmetrical,

p is an integer of 3 or more,

q is an integer of 2 or more and less than p,

and r is an integer satisfying r ═ p-q.

3. The light emitting device according to claim 2,

said q is an integer greater than half of said p.

4. A projector having the light-emitting device according to any one of claims 1 to 3.

Technical Field

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

Background

Semiconductor lasers are expected as next-generation light sources with high luminance. Among them, a semiconductor laser using a nanopillar is expected to realize high-output light emission at a narrow emission angle by the effect of a photonic crystal of the nanopillar. Such a semiconductor laser is used as a light source of a projector, for example. In a projector using a liquid crystal light valve, it is desirable that the light emitted from the light source is linearly polarized light.

In a semiconductor laser using a photonic crystal of GaN-based nanopillars, it is possible to design the semiconductor laser to match the wavelength of the three primary colors of RGB by changing the arrangement period or diameter of the nanopillars. However, in order to oscillate in the red region, it is necessary to use a nanopillar having a large diameter, and it is difficult to obtain the effect of a nanopillar having few defects or deformations and having good light emission efficiency. Therefore, the following techniques are known: a nanopillar assembly composed of a plurality of nanopillars having a small diameter is regarded as a nanopillar, and the nanopillar assembly is periodically arranged.

Here, as described in patent document 1, since the nano-pillars are arranged in a lattice pattern having rotational symmetry such as a triangle, a square, or a hexagon, light emitted from the light emitting device is not linearly polarized light.

Patent document 1: japanese patent laid-open publication No. 2013-9002

Even in the case where the nano-pillar assembly is formed of a plurality of nano-pillars as described above, when the nano-pillar assembly is arranged in a lattice pattern having rotational symmetry, the light emitted from the light emitting device is not linearly polarized light.

Disclosure of Invention

One embodiment of a light-emitting device of the present invention includes:

a substrate; and

a laminate provided on the base and having a columnar portion aggregate consisting of p columnar portions,

the laminate body has a plurality of the columnar portion aggregate,

the p columnar portions each have a light-emitting layer,

a pattern constituted by the centers of the p columnar portions is rotationally symmetric when viewed from the stacking direction of the stacked body,

the diameter of q of the p columnar portions is different from the diameter of r of the p columnar portions,

the shape of the columnar part aggregate is not rotationally symmetrical,

wherein p is an integer of 2 or more,

q is an integer of 1 or more and less than p,

and r is an integer satisfying r ═ p-q.

One embodiment of a light-emitting device of the present invention includes:

a substrate; and

a laminate provided on the base and having a columnar portion aggregate consisting of p columnar portions,

the laminate body has a plurality of the columnar portion aggregate,

the p columnar portions each have a light-emitting layer,

when the p lattice points that are rotationally symmetric are defined on the base when viewed from the stacking direction of the laminate, the centers of q columnar portions of the p columnar portions are arranged at the lattice points, and the centers of r columnar portions of the p columnar portions are arranged at positions different from the lattice points,

the shape of the columnar part aggregate is not rotationally symmetrical,

p is an integer of 3 or more,

q is an integer of 2 or more and less than p,

and r is an integer satisfying r ═ p-q.

In one mode of the light-emitting device,

said q is an integer greater than half of said p.

The projector according to the present invention includes one embodiment of the light-emitting device.

Drawings

Fig. 1 is a sectional view schematically showing a light-emitting device of embodiment 1.

Fig. 2 is a plan view schematically showing a light emitting device of embodiment 1.

Fig. 3 is a plan view schematically showing a columnar portion aggregate of the light-emitting device of embodiment 1.

Fig. 4 is a diagram for explaining polarized light.

Fig. 5 is a graph for explaining the intensity of light.

Fig. 6 is a diagram for explaining polarized light.

Fig. 7 is a sectional view schematically showing a manufacturing process of a light-emitting device according to embodiment 1.

Fig. 8 is a plan view schematically showing a columnar portion assembly of a light-emitting device according to modification 1 of embodiment 1.

Fig. 9 is a plan view schematically showing a columnar portion assembly of a light-emitting device according to modification 2 of embodiment 1.

Fig. 10 is a sectional view schematically showing a light-emitting device according to modification 3 of embodiment 1.

Fig. 11 is a plan view schematically showing a columnar portion aggregate of the light-emitting device of embodiment 2.

Fig. 12 is a plan view schematically showing a columnar portion assembly of a light-emitting device according to modification 1 of embodiment 2.

Fig. 13 is a plan view schematically showing a columnar portion assembly of a light-emitting device according to modification 2 of embodiment 2.

Fig. 14 is a diagram schematically showing a projector of embodiment 3.

Description of the reference symbols

10: a substrate; 20: a laminate; 22: a buffer layer; 30: a columnar portion; 30 a: the 1 st columnar part; 30 b: a 2 nd columnar portion; 31: 1 st semiconductor layer; 32: a 1 st guiding layer; 33: a light emitting layer; 34: a 2 nd guiding layer; 35: a 2 nd semiconductor layer; 40: a columnar portion aggregate; 50: a 1 st electrode; 52: a 2 nd electrode; 60: a mask layer; 62: an opening part; 100: a light emitting device; 100R: a red light source; 100G: a green light source; 100B: a blue light source; 110. 120, 130, 200, 210, 220: a light emitting device; 900: a projector; 902R: a 1 st lens array; 902G: a 2 nd lens array; 902B: a 3 rd lens array; 904R: 1 st light modulation device; 904G: a 2 nd light modulation device; 904B: a 3 rd light modulation device; 906: a cross dichroic prism; 908: a projection device.

Detailed Description

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The embodiments described below are not unreasonably restrictive to the contents of the present invention described in the claims. Moreover, not all of the structures described below are necessarily essential components of the present invention.

1. Embodiment 1

1.1. Light emitting device

First, a light-emitting device according to embodiment 1 will be described with reference to the drawings. Fig. 1 is a sectional view schematically showing a light-emitting device 100 of embodiment 1. Fig. 2 is a plan view schematically showing the light emitting device 100 of embodiment 1. In addition, fig. 1 is a sectional view taken along line I-I of fig. 2.

As shown in fig. 1 and 2, the light-emitting device 100 includes a substrate 10, a laminate 20, a 1 st electrode 50, and a 2 nd electrode 52. In fig. 2, the illustration of the 2 nd electrode 52 is omitted for the sake of convenience.

The substrate 10 has, for example, a plate-like shape. The substrate 10 is, for example, a Si substrate, a GaN substrate, a sapphire substrate, or the like.

The laminate 20 is provided on the substrate 10. In the illustrated example, the laminated body 20 is provided on the base 10. The laminate 20 includes, for example, the buffer layer 22 and the columnar portion 30.

In the present invention, "up" refers to a direction away from the substrate 10 when viewed from the light-emitting layer 33 of the columnar portion 30 in the stacking direction of the stacked body 20 (hereinafter, also simply referred to as "stacking direction"), and "down" refers to a direction toward the substrate 10 when viewed from the light-emitting layer 33 in the stacking direction.

In the present invention, the "lamination direction of the laminate 20" refers to the lamination direction of the 1 st semiconductor layer 31 and the light-emitting layer 33 of the columnar section 30.

The buffer layer 22 is disposed on the substrate 10. The buffer layer 22 is, for example, an n-type GaN layer doped with Si. A mask layer 60 for forming the columnar portion 30 is provided on the buffer layer 22.

The columnar portion 30 is provided on the buffer layer 22. The cross-sectional shape of the columnar portion 30 in the direction perpendicular to the stacking direction is, for example, a polygon, a circle, or the like. In the example shown in fig. 2, the cross-sectional shape of the columnar portion 30 is a regular hexagon. The diameter of the columnar portion 30 is, for example, on the order of nm, specifically, 10nm or more and 500nm or less. The columnar portion 30 is also called, for example, a Nanopillar (Nanocolumn), a nanowire, a nanorod, or a Nanopillar (Nanopillar). The size of the columnar portion 30 in the stacking direction is, for example, 0.1 μm or more and 5 μm or less.

In the present invention, the "diameter" refers to the diameter when the planar shape of the columnar portion 30 is a circle, and refers to the diameter of the smallest circle (i.e., the smallest enveloping circle) that includes a polygon inside when the planar shape of the columnar portion 30 is a polygon. The "planar shape" refers to a shape when viewed from the stacking direction.

As shown in fig. 1, the columnar portion 30 includes a 1 st semiconductor layer 31, a 1 st guide layer 32, a light-emitting layer 33, a 2 nd guide layer 34, and a 2 nd semiconductor layer 35.

The 1 st semiconductor layer 31 is disposed on the buffer layer 22. The 1 st semiconductor layer 31 is provided between the base 10 and the light emitting layer 33. The 1 st semiconductor layer 31 is, for example, an n-type GaN layer doped with Si.

The 1 st guide layer 32 is disposed on the 1 st semiconductor layer 31. The 1 st guide layer 32 has a diameter larger than that of the 1 st semiconductor layer 31. In the illustrated example, the diameter of the 1 st guide layer 32 varies in the stacking direction. The 1 st guiding layer 32 has, for example, a semiconductor Superlattice (SL) structure composed of a GaN layer and an InGaN layer. The number of GaN layers and InGaN layers constituting the 1 st guiding layer 32 is not particularly limited.

The light emitting layer 33 is disposed on the 1 st guide layer 32. The light emitting layer 33 is disposed between the 1 st semiconductor layer 31 and the 2 nd semiconductor layer 35. The light-emitting layer 33 is a layer capable of generating light by an injected current. The light-emitting layer 33 has, for example, a quantum well (MQW) structure composed of a GaN layer and an InGaN layer. The number of GaN layers and InGaN layers constituting the light emitting layer 33 is not particularly limited.

The 2 nd guide layer 34 is provided on the light emitting layer 33. The 2 nd guiding layer 34 has, for example, a semiconductor Superlattice (SL) structure composed of a GaN layer and an InGaN layer. The number of GaN layers and InGaN layers constituting the 2 nd guiding layer 34 is not particularly limited. The 1 st guide layer 32 and the 2 nd guide layer 34 are layers having the following functions: the overlap of the light propagating in the direction perpendicular to the stacking direction with the light-emitting layer 33 is made large, that is, the optical closure coefficient (optical notch Write め) is made large.

The 2 nd semiconductor layer 35 is disposed on the 2 nd guide layer 34. The 2 nd semiconductor layer 35 is a layer having a conductivity type different from that of the 1 st semiconductor layer 31. The 2 nd semiconductor layer 35 is, for example, a p-type GaN layer doped with Mg. The 1 st semiconductor layer 31 and the 2 nd semiconductor layer 35 are clad layers having a function of confining light in the light-emitting layer 33.

In the light-emitting device 100, the p-type 2 nd semiconductor layer 35, the impurity-undoped light-emitting layer 33, the 1 st guide layer 32, the 2 nd guide layer 34, and the n-type 1 st semiconductor layer 31 constitute a pin diode. In the light-emitting device 100, when a forward bias voltage of the pin diode is applied between the 1 st electrode 50 and the 2 nd electrode 52, a current is injected into the light-emitting layer 33 to cause recombination of electrons and holes in the light-emitting layer 33. Luminescence is generated by this recombination. The light generated in the light-emitting layer 33 propagates in the direction perpendicular to the stacking direction via the 1 st semiconductor layer 31 and the 2 nd semiconductor layer 35, forms a standing wave by the effect of photonic crystals generated by the plurality of columnar portions 30, and receives a gain in the light-emitting layer 33 to perform laser oscillation. Then, the light emitting device 100 emits the +1 st order diffracted light and the-1 st order diffracted light as laser light in the stacking direction.

Although not shown, a reflective layer may be provided between the substrate 10 and the buffer layer 22 or below the substrate 10. The reflective layer is, for example, a DBR (Distributed Bragg Reflector) layer. The light generated in the light-emitting layer 33 can be reflected by the reflective layer, and the light-emitting device 100 can emit light only from the 2 nd electrode 52 side.

The columnar portion 30 constitutes a columnar portion aggregate 40. As shown in fig. 2, the laminate 20 has a plurality of columnar portion aggregates 40. In the illustrated example, the plurality of columnar portion aggregates 40 are arranged in a triangular lattice shape. The distance between the centers of adjacent columnar portion aggregates 40 is 250nm or more and 350nm or less when viewed from the stacking direction. Here, fig. 3 is a plan view schematically showing the columnar part aggregate 40.

As shown in fig. 2 and 3, the columnar portion aggregate 40 is composed of p columnar portions 30. "p" is an integer of 2 or more, for example, an integer of 3 or more and 15 or less, preferably an integer of 3 or more and 7 or less. In the illustrated example, "p" is 7, and the columnar portion aggregate 40 is composed of 7 columnar portions 30. The columnar portion aggregate 40 is an aggregate of columnar portions 30 that can oscillate light in the red region. In the columnar portion aggregate 40, the distance between the centers of the adjacent columnar portions 30 is 50nm or more and 150nm or less as viewed from the stacking direction. The P columnar portions 30 each have a light-emitting layer 33.

In the columnar portion aggregate 40, as shown in fig. 3, for example, a pattern F formed by the centers C of the p columnar portions 30 is rotationally symmetric when viewed from the stacking direction. That is, when n is an integer of 2 or more, the pattern F is symmetrical n times. In the illustrated example, the pattern F is 6-fold symmetric. Since the pattern F formed of, for example, 3 or more centers C is rotationally symmetric as described above, light resonating in a plurality of directions can be further isotropically blocked in a direction perpendicular to the lamination direction, as compared with a case where the pattern F is not rotationally symmetric, for example, a case where 3 or more columnar portions are arranged in 1 straight line, and the columnar portion aggregate 40 capable of oscillating light in the red region can be easily formed. For example, since a periodic structure having the same refractive index in 3 directions can be formed, light resonating in 3 directions can be confined in the same manner. Therefore, there is no direction in which light is easily leaked in the 3 direction of resonance, and light can be effectively blocked. In the illustrated example, the center C of the columnar portion 30 is disposed at each vertex of a regular hexagon, not shown, and at the center of the regular hexagon. The center of the regular hexagon overlaps the center of the columnar portion aggregate 40. For example, although not shown, a graph formed by line segments connecting adjacent centers C is rotationally symmetric.

In the columnar section aggregate 40, the diameter D1 of q 1 st columnar sections 30a among the p columnar sections 30 is different from the diameter D2 of r 2 nd columnar sections 30b among the p columnar sections 30 when viewed from the stacking direction. The diameter D2 of the 2 nd columnar section 30b is smaller than the diameter D1 of the 1 st columnar section 30 a. "q" is an integer of 1 or more and less than p. "r" is an integer satisfying r ═ p-q.

In the illustrated example, "q" is 6 and "r" is 1. Since the columnar portion aggregate 40 has the 2 nd columnar portion 30b smaller than the 1 st columnar portion 30a, the shape of the columnar portion aggregate 40 is not rotationally symmetrical when viewed from the stacking direction. That is, when m is an integer of 2 or more, the shape of the columnar portion aggregate 40 is not m-th order symmetric. The 2 nd columnar portion 30b is arranged so as not to overlap with the center of the columnar portion aggregate 40.

Here, the "diameter of the columnar portion" is the largest diameter among the diameter of the 1 st semiconductor layer 31, the diameter of the 1 st guide layer 32, the diameter of the light emitting layer 33, the diameter of the 2 nd guide layer 34, and the diameter of the 2 nd semiconductor layer 35 of the columnar portion 30. In the illustrated example, the diameter of the 1 st semiconductor layer 31, the diameter of the 1 st guide layer 32, the diameter of the light-emitting layer 33, the diameter of the 2 nd guide layer 34, and the diameter of the 2 nd semiconductor layer 35 in the 2 nd columnar portion 30b are smaller than the diameter of the 1 st semiconductor layer 31, the diameter of the 1 st guide layer 32, the diameter of the light-emitting layer 33, the diameter of the 2 nd guide layer 34, and the diameter of the 2 nd semiconductor layer 35 in the 1 st columnar portion 30a, respectively. The diameter of the light-emitting layer 33, the diameter of the 2 nd guiding layer 34, and the diameter of the 2 nd semiconductor layer 35 are, for example, the same.

Although not shown, the column portion assembly 40 may have a plurality of the 2 nd column portions 30 b. However, if the number of the 2 nd columnar portions 30b having a small diameter is 1, the region in which light propagating in the direction perpendicular to the stacking direction overlaps with the light-emitting layer 33 can be increased.

The 1 st electrode 50 is disposed on the buffer layer 22. The buffer layer 22 may be in ohmic contact with the 1 st electrode 50. The 1 st electrode 50 is electrically connected to the 1 st semiconductor layer 31. In the illustrated example, the 1 st electrode 50 is electrically connected to the 1 st semiconductor layer 31 via the buffer layer 22. The 1 st electrode 50 is one electrode for injecting current into the light-emitting layer 33. As the 1 st electrode 50, for example, an electrode in which a Ti layer, an Al layer, and an Au layer are laminated in this order from the buffer layer 22 side is used. When the substrate 10 is conductive, the 1 st electrode 50 may be provided below the substrate 10, although not shown.

The 2 nd electrode 52 is disposed on the 2 nd semiconductor layer 35. The 2 nd semiconductor layer 35 may be in ohmic contact with the 2 nd electrode 52. The 2 nd electrode 52 is electrically connected to the 2 nd semiconductor layer 35. The 2 nd electrode 52 is another electrode for injecting current into the light-emitting layer 33. For example, ITO (indium tin oxide) or the like is used as the 2 nd electrode 52.

In addition, although the InGaN-based light emitting layer 33 is described above, all material-based light emitting layers that can emit light by being injected with current can be used as the light emitting layer 33 of the present invention. For example, semiconductor materials such as AlGaN, AlGaAs, InGaAs, InGaAsP, InP, GaP, and AlGaP can be used.

The light-emitting device 100 has the following features, for example.

In the light-emitting device 100, the diameter D1 of q 1 st columnar sections 30a of the p columnar sections 30 is different from the diameter D2 of r 2 nd columnar sections 30b of the p columnar sections 30, and the shape of the columnar section aggregate 40 is not rotationally symmetric. Therefore, the light emitted from the light emitting device 100 is linearly polarized light. Therefore, the light-emitting device 100 is suitable for use as a light source of a projector using a liquid crystal light valve. The light emitting device 100 can emit light having a single peak property, for example.

Here, fig. 4 is a diagram for explaining polarized light in the case where the shape of the columnar portion aggregate is rotationally symmetric. Fig. 5 is a graph for explaining the intensity of light of the V-V line shown in fig. 4. Fig. 6 is a diagram for explaining polarized light of the light-emitting device 100. When the shape of the columnar portion aggregate is rotationally symmetric, for example, as shown in fig. 4, the vibration directions of the electric field E of the emitted light L at the respective positions do not coincide, and as shown in fig. 4 and 5, the electric fields E cancel each other out at the central portion, and the shape of the emitted light L (i.e., the shape of the light flux) is annular. On the other hand, in the light emitting device 100, as shown in fig. 6, the vibration directions of the electric field E are all the same, and the light emitted from the light emitting device 100 is linearly polarized light. In the example shown in fig. 6, the shape of the emitted light L is a circle. I.e. unimodal.

In the light-emitting device 100, the shape of the columnar section aggregate 40 is not rotationally symmetrical by making the diameter of the 1 st columnar section 30a different from the diameter of the 2 nd columnar section 30b, and therefore, for example, the 2 nd electrode 52 is less likely to go around the side surface of the columnar section 30 than in the case where the shape of the columnar section aggregate is not rotationally symmetrical by reducing the columnar sections of one rotationally symmetrical columnar section aggregate. Therefore, for example, a leakage current is not easily generated. Further, the region in which light propagating in the direction perpendicular to the stacking direction overlaps with the light-emitting layer 33 can be increased.

1.2. Method for manufacturing light emitting device

Next, a method for manufacturing the light-emitting device 100 according to embodiment 1 will be described with reference to the drawings. Fig. 7 is a sectional view schematically showing a manufacturing process of the light emitting device 100 according to embodiment 1.

As shown in fig. 7, the buffer layer 22 is epitaxially grown on the substrate 10. Examples of the method of epitaxial growth include the MOCVD (Metal Organic Chemical Vapor Deposition) method and the MBE (Molecular Beam Epitaxy) method.

Next, a mask layer 60 is formed on the buffer layer 22. The mask layer 60 is formed by forming a film by an electron beam evaporation method, a plasma CVD (Chemical Vapor Deposition) method, or the like, and patterning the film by a photolithography technique and an etching technique, for example. The opening 62 of the mask layer 60 for forming the 2 nd columnar portion 30b is smaller in area than the opening 62 of the mask layer 60 for forming the 1 st columnar portion 30a when viewed from the lamination direction. This makes it possible to make the diameter of the 2 nd columnar portion 30b smaller than that of the 1 st columnar portion 30 a.

As shown in fig. 1, the 1 st semiconductor layer 31, the 1 st guide layer 32, the light-emitting layer 33, the 2 nd guide layer 34, and the 2 nd semiconductor layer 35 are epitaxially grown on the buffer layer 22 in this order using the mask layer 60 as a mask. Examples of the method of epitaxial growth include MOCVD and MBE. Through the above steps, the columnar portion aggregate 40 including the plurality of columnar portions 30 can be formed.

Next, the 1 st electrode 50 is formed on the buffer layer 22, and the 2 nd electrode 52 is formed on the 2 nd semiconductor layer 35. The 1 st electrode 50 and the 2 nd electrode 52 are formed by, for example, a vacuum evaporation method. In addition, the order of forming the 1 st electrode 50 and the 2 nd electrode 52 is not particularly limited.

Through the above steps, the light-emitting device 100 can be manufactured.

1.3. Modification of light emitting device

1.3.1. Modification example 1

Next, a light-emitting device according to variation 1 of embodiment 1 will be described with reference to the drawings. Fig. 8 is a plan view schematically showing a columnar portion aggregate 40 of a light-emitting device 110 according to modification 1 of embodiment 1.

Hereinafter, in the light-emitting device 110 according to variation 1 of embodiment 1, points different from those of the light-emitting device 100 according to embodiment 1 will be described, and description of the same points will be omitted. This is the same for the light-emitting devices of modifications 2 and 3 of embodiment 1 described below.

In the light-emitting device 100, as shown in fig. 3, the columnar portion aggregate 40 is composed of 7 columnar portions 30. In contrast, in the light-emitting device 110, as shown in fig. 8, the columnar portion aggregate 40 is composed of 4 columnar portions 30. In the illustrated example, the pattern F formed by the centers C of the 4 columnar portions 30 is symmetrical 2 times. The center C of the columnar portion 30 is disposed at each vertex of a diamond shape, not shown.

1.3.2. Modification example 2

Next, a light-emitting device according to variation 2 of embodiment 1 will be described with reference to the drawings. Fig. 9 is a plan view schematically showing a columnar portion aggregate 40 of a light-emitting device 120 according to modification 2 of embodiment 1.

In the light-emitting device 100, as shown in fig. 3, the columnar portion aggregate 40 is composed of 7 columnar portions 30. In contrast, in the light-emitting device 120, as shown in fig. 9, the columnar portion aggregate 40 is composed of 3 columnar portions 30. In the illustrated example, the pattern F formed by the centers C of the 3 columnar portions 30 is 3-fold symmetric. The center C of the columnar portion 30 is disposed at each vertex of a regular triangle not shown.

The number of the plurality of columnar parts constituting the columnar part aggregate of the present invention is not limited to the above-described 3, 4, or 7 examples.

1.3.3. Modification 3

Next, a light-emitting device according to modification 3 of embodiment 1 will be described with reference to the drawings. Fig. 10 is a plan view schematically showing a light-emitting device 130 according to modification 3 of embodiment 1.

In the light-emitting device 100, as shown in fig. 1, the diameter of the light-emitting layer 33 is the same as the diameter of the 2 nd semiconductor layer 35 in the columnar portion 30. In contrast, in the light-emitting device 130, as shown in fig. 10, the diameter of the 2 nd semiconductor layer 35 is larger than that of the light-emitting layer 33.

In the illustrated example, the diameter of the 1 st guide layer 32, the diameter of the light-emitting layer 33, and the diameter of the 2 nd guide layer 34 are the same. For example, by adjusting the growth temperature at the time of epitaxially growing the 1 st guide layer 32, the light-emitting layer 33, the 2 nd guide layer 34, and the 2 nd semiconductor layer 35, the diameter of the 2 nd semiconductor layer 35 can be made larger than the diameter of the 1 st guide layer 32, the diameter of the light-emitting layer 33, and the diameter of the 2 nd guide layer 34.

2. Embodiment 2

2.1. Light emitting device

Next, a light-emitting device according to embodiment 2 will be described with reference to the drawings. Fig. 11 is a plan view schematically showing the columnar portion aggregate 40 of the light-emitting device 200 according to embodiment 2.

Hereinafter, in the light-emitting device 200 of embodiment 2, points different from the example of the light-emitting device 100 of embodiment 1 will be described, and description of the same points will be omitted.

In the light-emitting device 100, as shown in fig. 3, the diameter D1 of the 1 st columnar portion 30a is different from the diameter D2 of the 2 nd columnar portion 30b when viewed from the stacking direction. In contrast, in the light-emitting device 200, as shown in fig. 11, for example, the diameter of the 1 st columnar portion 30a is the same as the diameter of the 2 nd columnar portion 30b when viewed from the stacking direction.

The light-emitting device 200 has a columnar portion aggregate 40 composed of p columnar portions 30. When p lattice points G that are rotationally symmetric are defined on the substrate 10 when viewed from the stacking direction, the centers C of the q 1 st columnar portions 30a of the p columnar portions 30 are arranged at the lattice points G. The center C of each of the r 2 nd columnar portions 30b of the p columnar portions 30 is arranged at a position different from the lattice point G. The lattice point G is a virtual point defined on the substrate 10 when viewed from the lamination direction. "p" is an integer of 3 or more. "q" is an integer of 2 or more and less than p, for example, an integer larger than half of "p". "r" is an integer satisfying r ═ p-q.

In the illustrated example, "p" is 7, "q" is 6, and "r" is 1. The pattern of p lattice points G is 6 times symmetrical. The lattice points G are arranged at the respective vertices of a regular hexagon and the center of the regular hexagon, not shown. The distance between the center C of the 2 nd columnar portion 30b and the lattice point G closest to the center C of the 2 nd columnar portion 30b is, for example, 5nm or more and 25nm or less.

Since the columnar portion aggregate 40 has the 2 nd columnar portion 30b having the center C at a position different from the lattice point G, the shape of the columnar portion aggregate 40 is not rotationally symmetrical when viewed from the lamination direction.

The light-emitting device 200 has the following features, for example.

In the light-emitting device 200, when p lattice points G that are rotationally symmetric are defined on the substrate 10 when viewed from the stacking direction, the centers C of q 1 st columnar portions 30a of the p columnar portions 30 are arranged at the lattice points G, the centers C of r 2 nd columnar portions 30b of the p columnar portions 30 are arranged at positions different from the lattice points G, and the shape of the columnar portion aggregate is not rotationally symmetric. Therefore, the light emitted from the light emitting device 200 is linearly polarized light, as in the light emitting device 100. Further, by having the 2 nd columnar portion 30b having the center C at a position different from the lattice point G, the shape of the columnar portion aggregate 40 is not rotationally symmetric, and therefore, for example, compared to a case where the shape of the columnar portion aggregate 40 is not rotationally symmetric by making the diameter of the 1 st columnar portion 30a different from the diameter of the 2 nd columnar portion 30b, a region where light propagating in a direction perpendicular to the lamination direction overlaps with the light-emitting layer 33 can be increased.

In the light-emitting device 200, "q" is an integer larger than half of "p". Therefore, more than half of the p columnar portions 30 can be arranged at the lattice point G. Thus, in the light-emitting device 200, compared to the case where more than half of the p columnar portions 30 are not arranged at the lattice point G, for example, light resonating in a plurality of directions can be further isotropically blocked in the direction perpendicular to the stacking direction, and the columnar portion aggregate 40 capable of oscillating light in the red region can be easily configured. In the light emitting device 200, for example, since the periodic structure having the same refractive index in a plurality of directions can be formed, light resonating in a plurality of directions can be confined in the same manner, which is advantageous for confining light.

2.2. Method for manufacturing light emitting device

Next, a method for manufacturing the light-emitting device 200 according to embodiment 2 will be described. The method of manufacturing the light-emitting device 200 of embodiment 2 is basically the same as the method of manufacturing the light-emitting device 100 of embodiment 1. Therefore, detailed description thereof is omitted.

2.3. Modification of light emitting device

2.3.1. Modification example 1

Next, a light-emitting device according to variation 1 of embodiment 2 will be described with reference to the drawings. Fig. 12 is a plan view schematically showing a columnar portion aggregate 40 of a light-emitting device 210 according to modification 1 of embodiment 2.

Hereinafter, in the light-emitting device 210 according to variation 1 of embodiment 2, points different from the example of the light-emitting device 200 according to embodiment 2 will be described, and description of the same points will be omitted. This is the same in the light-emitting device according to modification 2 of embodiment 2 described below.

In the light-emitting device 200, as shown in fig. 11, the columnar portion aggregate 40 is composed of 7 columnar portions 30. In contrast, in the light-emitting device 210, as shown in fig. 12, the columnar portion aggregate 40 is composed of 4 columnar portions 30. In the illustrated example, the lattice points G are arranged at the vertices of a diamond, not shown.

2.3.2. Modification example 2

Next, a light-emitting device according to variation 2 of embodiment 2 will be described with reference to the drawings. Fig. 13 is a plan view schematically showing a columnar portion assembly 40 of a light-emitting device 220 according to modification 2 of embodiment 2.

In the light-emitting device 200, as shown in fig. 11, the columnar portion aggregate 40 is composed of 7 columnar portions 30. In contrast, in the light-emitting device 220, as shown in fig. 13, the columnar portion aggregate 40 is composed of 3 columnar portions 30. In the illustrated example, the lattice points G are arranged at the vertices of a regular triangle diamond, not shown.

3. Embodiment 3

Next, a projector according to embodiment 3 will be described with reference to the drawings. Fig. 14 is a diagram schematically illustrating a projector 900 according to embodiment 3.

The projector of the present invention has the light-emitting device of the present invention. Hereinafter, a projector 900 including the light-emitting device 100 as the light-emitting device of the present invention will be described.

The projector 900 includes a casing, not shown, and a red light source 100R, a green light source 100G, and a blue light source 100B that emit red light, green light, and blue light, respectively, provided in the casing. The red light source 100R, the green light source 100G, and the blue light source 100B are, for example, each configured as follows: the plurality of light-emitting devices 100 are arranged in an array in a direction perpendicular to the stacking direction, and the base 10 is a common substrate in the plurality of light-emitting devices 100. The number of light emitting devices 100 constituting the red light source 100R, the green light source 100G, and the blue light source 100B is not particularly limited. In addition, in fig. 14, the red light source 100R, the green light source 100G, and the blue light source 100B are simplified for convenience.

The projector 900 further includes a 1 st lens array 902R, a 2 nd lens array 902G, a 3 rd lens array 902B, a 1 st light modulation device 904R, a 2 nd light modulation device 904G, a 3 rd light modulation device 904B, and a projection device 908, which are provided in the housing. The 1 st light modulation device 904R, the 2 nd light modulation device 904G, and the 3 rd light modulation device 904B are, for example, transmissive liquid crystal light valves. The projection device 908 is, for example, a projection lens.

Light emitted from the red light source 100R is incident on the 1 st lens array 902R. The light emitted from the red light source 100R can be condensed by the 1 st lens array 902R, and can be overlapped, for example.

The light condensed by the 1 st lens array 902R is incident on the 1 st light modulation device 904R. The 1 st light modulation device 904R modulates the incident light in accordance with the image information. Then, the projection device 908 enlarges and projects an image formed by the 1 st light modulation device 904R onto the screen 910.

Light emitted from the green light source 100G is incident on the 2 nd lens array 902G. The light emitted from the green light source 100G can be condensed by the 2 nd lens array 902G, and can be overlapped, for example.

The light condensed by the 2 nd lens array 902G is incident on the 2 nd light modulation device 904G. The 2 nd light modulation device 904G modulates the incident light according to the image information. Then, the projection device 908 enlarges and projects the image formed by the 2 nd light modulation device 904G onto the screen 910.

Light emitted from the blue light source 100B is incident on the 3 rd lens array 902B. The light emitted from the blue light source 100B can be condensed by the 3 rd lens array 902B, and can be overlapped, for example.

The light condensed by the 3 rd lens array 902B is incident on the 3 rd light modulation device 904B. The 3 rd light modulation device 904B modulates the incident light according to the image information. Then, the projection device 908 enlarges and projects an image formed by the 3 rd light modulation device 904B onto the screen 910.

The projector 900 may further include a cross dichroic prism 906 that combines the light emitted from the 1 st light modulation device 904R, the 2 nd light modulation device 904G, and the 3 rd light modulation device 904B and guides the combined light to the projector 908.

The 3 color lights modulated by the 1 st light modulation device 904R, the 2 nd light modulation device 904G, and the 3 rd light modulation device 904B are incident on the cross dichroic prism 906. The cross dichroic prism 906 is formed by bonding 4 rectangular 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. The 3 color lights are synthesized by these dielectric multilayer films to form light representing a color image. The combined light is then projected onto a screen 910 by a projection device 908, and an enlarged image is displayed.

The projector 900 includes a light-emitting device 100 capable of emitting light as linearly polarized light. Therefore, in the projector 900, the control of passing and blocking of light in the 1 st light modulation device 904R, the 2 nd light modulation device 904G, and the 3 rd light modulation device 904B can be performed more reliably.

The application of the light-emitting device of the present invention is not limited to the above embodiment, and the light-emitting device may be used in devices other than a projector. Other applications than projectors include light sources for indoor and outdoor lighting, backlights of displays, laser printers, scanners, in-vehicle lamps, sensor devices using light, communication devices, and the like.

The present invention may omit a part of the configuration or combine the embodiments and the modifications within the scope of having the features and effects described in the present application.

The present invention is not limited to the above embodiment, and various modifications can be made. For example, the present invention includes substantially the same structure as that described in the embodiment. The substantially same structure is, for example, a structure having the same function, method, and result, or a structure having the same purpose and effect. The present invention includes a structure obtained by replacing a non-essential part of the structure described in the embodiment. The present invention includes a configuration that can achieve the same operational effects or the same objects as the configurations described in the embodiments. The present invention includes a configuration in which a known technique is added to the configuration described in the embodiment.