JP7206628B2 - Light-emitting device and projector - Google Patents

Description

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

Mercury lamps, which have long been widely used as light sources for projectors, have problems with their lifespan, such as gradual dimming and sudden burnout, as well as problems with mercury regulations. ing.

For example, in Patent Document 1, 300 (15×20) LED lamps having a plurality of LED chips are arranged two-dimensionally on an LED substrate at an arrangement pitch of 4 mm, and the output light of the LED lamps is collimated by a microlens array. A projector with light is described.

JP 2006-317935 A

The light source (light emitting device) of the projector as described above is desired to efficiently illuminate an illumination target such as a screen.

One aspect of the light-emitting device according to the present invention is
a plurality of light-emitting units each having a light-emitting element and a lens provided corresponding to the light-emitting element;
The light emitting element is
a first semiconductor layer;
a second semiconductor layer having a conductivity type different from that of the first semiconductor layer;
a light-emitting layer provided between the first semiconductor layer and the second semiconductor layer and capable of generating light by current injection;
a first electrode electrically connected to the first semiconductor layer;
a second electrode in contact with the second semiconductor layer;
has
The second electrode overlaps the light-emitting layer in a plan view viewed from the stacking direction of the first semiconductor layer and the light-emitting layer,
In a plan view viewed from the stacking direction, the plurality of light emitting units are arranged at a pitch p in the first direction,
The size d in the first direction and the pitch p of the contact region between the second semiconductor layer and the second electrode are
d/p≦0.5, d≧2 μm, and p≦12 μm
satisfy the relationship

In one aspect of the light-emitting device,
The size d and the pitch p are
0.4≦d/p≦0.5
may satisfy the relationship of

In one aspect of the light-emitting device,
The size d and the pitch p are
d/p≦0.3
may satisfy the relationship of

In one aspect of the light-emitting device,
a first light emitting element among the plurality of light emitting elements is adjacent to a second light emitting element among the plurality of light emitting elements;
The light emitted from the first light emitting element may not be totally reflected by the lens provided corresponding to the second light emitting element among the plurality of lenses.

In one aspect of the light-emitting device,
One aspect of the projector according to the present invention is
an aspect of the light-emitting device;
a projection device for projecting light emitted from the light emitting device;
have

BRIEF DESCRIPTION OF THE DRAWINGS Sectional drawing which shows typically the light-emitting device which concerns on 1st Embodiment. 1 is a plan view schematically showing a light emitting device according to a first embodiment; FIG. 4A to 4C are cross-sectional views schematically showing manufacturing steps of the light emitting device according to the first embodiment; Sectional drawing which shows typically the light-emitting device which concerns on 2nd Embodiment. The top view which shows typically the light-emitting device which concerns on 2nd Embodiment. Sectional drawing which shows typically the light-emitting device which concerns on 3rd Embodiment. FIG. 2 is a cross-sectional view schematically showing a light emitting device according to a reference example; Sectional drawing which shows typically the light-emitting device which concerns on 3rd Embodiment. A graph showing the minimum radius of curvature of a lens. A graph showing the minimum radius of curvature of a lens. Graph showing projection efficiency. Graph showing projection efficiency. Graph showing projection efficiency. Sectional drawing which shows typically the light-emitting device which concerns on the modification of 3rd Embodiment. FIG. 2 is a cross-sectional view schematically showing a light emitting device according to a reference example; Sectional drawing which shows typically the light-emitting device which concerns on the modification of 3rd Embodiment. Sectional drawing which shows typically the light-emitting device which concerns on the modification of 3rd Embodiment. Sectional drawing which shows typically the light-emitting device which concerns on the modification of 3rd Embodiment. The figure which shows typically the projector which concerns on 4th Embodiment. The figure which shows typically the projector based on the 1st modification of 4th Embodiment. The figure which shows typically the projector based on the 2nd modification of 4th Embodiment. 4 is a graph showing the relationship between the size of the contact area and the projection efficiency; 4 is a graph showing the relationship between the size of the contact area and the projected luminous flux; 4 is a graph showing the relationship between current density and optical power density; Graph showing the relationship between the size of the contact area and the current density and total current amount. 4 is a graph showing the relationship between the size of the contact area and the projected luminous flux; A graph showing the relationship between the size of the contact area and efficiency. 4 is a graph showing the relationship between the ratio of the size of the contact area to the pitch and the projected luminous flux; 5 is a graph showing the relationship between the ratio of contact area size to pitch and efficiency.

Preferred embodiments of the present invention will be described in detail below with reference to the drawings. It should be noted that the embodiments described below do not unduly limit the scope of the invention described in the claims. Moreover, not all the configurations described below are essential constituent elements of the present invention.

1. First Embodiment 1.1. Light Emitting Device First, the light emitting device according to the first embodiment will be described with reference to the drawings. FIG. 1 is a cross-sectional view schematically showing a light emitting device 100 according to the first embodiment. FIG. 2 is a plan view schematically showing the light emitting device 100 according to the first embodiment. 1 is a sectional view taken along line II of FIG. 1 and 2, X-axis, Y-axis, and Z-axis are illustrated as three mutually orthogonal axes.

The light emitting device 100 has, for example, a substrate 10, a light emitting element 20, an insulating layer 40, and a lens 50, as shown in FIGS. For convenience, the illustration of the second electrode 32 and the insulating layer 40 of the light emitting element 20 is omitted in FIG.

Substrate 10 is, for example, a sapphire substrate. The substrate 10 can transmit light generated in the light emitting layer 24 of the light emitting element 20, for example.

The light emitting element 20 is provided on the substrate 10 . A plurality of light emitting elements 20 are provided. As shown in FIG. 2, the plurality of light emitting elements 20 are arranged in a plan view from the stacking direction (the Z-axis direction in the illustrated example) of the first semiconductor layer 22 and the light emitting layer 24 of the light emitting elements 20 (hereinafter simply referred to as " In a plan view), they are provided in a matrix. The plurality of light emitting elements 20 are arranged at a pitch p in a first direction (eg, X-axis direction) and a second direction (eg, Y-axis direction) orthogonal to the first direction. The number of light-emitting elements 20 is not particularly limited, but is, for example, about 10000 (100×100, 100 in the X-axis direction and 100 in the Y-axis direction). The light emitting element 20 is, for example, an LED. In the illustrated example, the plurality of light emitting elements 20 is a square array arranged at a pitch p in a first direction and a second direction orthogonal to the first direction. It may be a hexagonal array arranged at a pitch p in a direction and in a second direction that is 60° from the first direction.

In the present invention, "upper" means the direction away from the substrate 10 when viewed from the light emitting layer 24 of the light emitting element 20 in the lamination direction of the first semiconductor layer 22 and the light emitting layer 24 of the light emitting element 20. “Lower” means the direction toward the substrate 10 when viewed from the light emitting layer 24 in the stacking direction. In the illustrated example, "top" is the +Z-axis direction side, and "bottom" is the -Z-axis direction side.

The light emitting element 20 has, for example, a first semiconductor layer 22, a light emitting layer 24, a second semiconductor layer 26, a first electrode 30, and a second electrode 32, as shown in FIG. .

The first semiconductor layer 22 is provided on the substrate 10 . The first semiconductor layer 22 is provided between the substrate 10 and the light emitting layer 24 . The thickness of the first semiconductor layer 22 is, for example, about 5 μm. The first semiconductor layer 22 is, for example, an n-type GaN layer doped with Si. In the illustrated example, the first semiconductor layer 22 is continuous in the adjacent light emitting elements 20 , and the first semiconductor layer 22 is one common layer in the plurality of light emitting elements 20 .

A portion of the first semiconductor layer 22, the light emitting layer 24, and the second semiconductor layer 26 constitute, for example, a columnar portion 28. As shown in FIG. In the plurality of light emitting elements 20, the columnar portions 28 are provided separately from each other. In the example shown in FIG. 2, the shape of the columnar portion 28 is square in plan view.

The light emitting layer 24 is provided on the first semiconductor layer 22 as shown in FIG. The light emitting layer 24 is provided between the first semiconductor layer 22 and the second semiconductor layer 26 . The light-emitting layer 24 has, for example, a multiple quantum well (MQW) structure in which five pairs of InGaN layers with a thickness of about 2.5 nm and GaN layers with a thickness of about 12 nm are alternately stacked. The light-emitting layer 24 is a layer capable of generating light when current is injected.

The second semiconductor layer 26 is provided on the light emitting layer 24 . The thickness of the second semiconductor layer 26 is, for example, about 150 nm. The second semiconductor layer 26 is a layer having a conductivity type different from that of the first semiconductor layer 22 . The second semiconductor layer 26 is, for example, a p-type GaN layer doped with Mg.

In the light-emitting device 100, the p-type second semiconductor layer 26, the impurity-undoped light-emitting layer 24, and the n-type first semiconductor layer 22 form a pin diode. The semiconductor layers 22 and 26 are layers having a bandgap larger than that of the light emitting layer 24 . In the light-emitting device 100 , when a forward bias voltage of a pin diode is applied (when a current is injected) between the first electrode 30 and the second electrode 32 , recombination of electrons and holes occurs in the light-emitting layer 24 . This recombination produces light emission.

Light generated in the light-emitting layer 24 (light directed in the −Z-axis direction) is transmitted through the substrate 10 and emitted. Light generated in the light emitting layer 24 (light directed in the +Z-axis direction) is reflected by the second electrode 32, for example. In FIG. 1, arrows indicate light (rays) generated in the light-emitting layer 24 and transmitted through the substrate 10 .

The first electrode 30 is provided on the first semiconductor layer 22 . In the illustrated example, the first electrode 30 is in contact with the first semiconductor layer 22 . The first electrode 30 may be in ohmic contact with the first semiconductor layer 22 . The first electrode 30 is electrically connected to the first semiconductor layer 22 .

The first electrode 30 is one electrode for injecting current into the light emitting layer 24 . As the first electrode 30, for example, a Ti layer and an Al layer are laminated in this order from the first semiconductor layer 22 side. In the example shown in FIG. 2, the first electrodes 30 of the adjacent light emitting elements 20 are continuous, and the first electrodes 30 of the plurality of light emitting elements 20 are provided in a grid pattern as one common electrode. there is The first electrode 30 is spaced apart from the columnar portion 28 and provided so as to surround the columnar portion 28 .

The second electrode 32 is provided on the second semiconductor layer 26 as shown in FIG. The second electrode 32 is in contact with the second semiconductor layer 26 . The second electrode 32 may be in ohmic contact with the second semiconductor layer 26 . The second electrode 32 overlaps the light emitting layer 24 in plan view. The second electrode 32 is electrically connected to the second semiconductor layer 26 . In the illustrated example, the second electrode 32 is also provided on the insulating layer 40 .

The second electrode 32 is the other electrode for injecting current into the light emitting layer 24 . The material of the second electrode 32 is, for example, a conductor having a high reflectance with respect to the light generated in the light emitting layer 24, such as an APC alloy that is an alloy of Ag, Pd and Cu. In the illustrated example, the second electrodes 32 are continuous in the adjacent light emitting elements 20 , and the second electrode 32 is one common electrode in the plurality of light emitting elements 20 .

The contact area 34 between the second electrode 32 and the second semiconductor layer 26 is square, as shown in FIG. The contact area 34 is the contact surface between the second electrode 32 and the second semiconductor layer 26 . The plurality of contact areas 34 are provided in a matrix in plan view. The plurality of contact areas 34 are
For example, they are arranged at a pitch p in the X-axis direction and the Y-axis direction.

The insulating layer 40 is provided around the columnar portion 28 and on the first semiconductor layer 22 and the first electrode 30, as shown in FIG. The insulating layer 40 electrically separates the first electrode 30 and the second electrode 32 . The insulating layer 40 is, for example, a silicon oxide layer (eg, SiO ₂ layer).

A lens 50 is provided below the substrate 10 . The lens 50 is adhered, for example, to the bottom surface of the substrate 10 . In the illustrated example, the lens 50 is a convex lens having a flat entrance surface 51a on the substrate 10 side and a curved exit surface 51b on the side opposite to the substrate 10 . A plurality of lenses 50 are provided. A plurality of lenses 50 constitute a lens array 52 . Lens array 52 is, for example, a microlens array (MLA).

Lens 50 is provided corresponding to light emitting element 20 . That is, light emitted from one light emitting element 20 enters one lens 50 . In the illustrated example, the columnar portion 28 of one light emitting element 20 is arranged inside the outer edge of one lens 50 when viewed from the Z-axis direction. The material of the lens 50 is glass, for example. The lens 50 can narrow the radiation angle of the light emitted in Lambertian from the light emitting element 20 .

The center position of the lens 50 is, for example, the same as the center position of the contact area 34 in plan view. The plurality of lenses 50 are arranged in a matrix in plan view. The plurality of lenses 50 are arranged at a pitch p in, for example, the X-axis direction and the Y-axis direction in plan view.

The light-emitting element 20 and the lens 50 constitute a plurality of light-emitting units 2 . That is, the light-emitting device 100 has a plurality of light-emitting units 2 each having a light-emitting element 20 and a lens 50 provided corresponding to the light-emitting element 20 . The plurality of light emitting units 2 are arranged at a pitch p in, for example, the X-axis direction and the Y-axis direction in plan view.

The size d of the contact region 34 between the second semiconductor layer 26 and the second electrode 32 in the X-axis direction and the pitch p of the light-emitting units 2 in the X-axis direction are given by the following equations (1), (2), and (3). satisfy the relationship

d/p≦0.5 (1)
d≧2 μm (2)
p≦12 μm (3)

From formulas (1), (2), and (3), the size d is 2 μm or more and 6 μm or less, and the pitch p is 4 μm or more and 12 μm or less.

The size d and the pitch p may satisfy the following formula (4) or the following formula (5).

0.4≦d/p≦0.5 (4)
d/p≦0.3 (5)

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

In the light-emitting device 100, the size d of the contact region 34 between the second semiconductor layer 26 and the second electrode 32 in the X-axis direction and the pitch p of the light-emitting units 2 in the X-axis direction satisfy d/p≦0.5, It satisfies the relationship of d≧2 μm and p≦12 μm. Therefore, the light-emitting device 100 can efficiently illuminate an illumination target such as a screen compared to a light-emitting device outside the above range (for details, see "Experimental Examples" described later). As a result, power saving can be achieved in the light emitting device 100 .

In the light emitting device 100, the size d and the pitch p may satisfy the relationship 0.4≦d/p≦0.5. Such a light-emitting device 100 can achieve higher luminance than a light-emitting device outside the above range (for details, see "Experimental Example" described later).

In the light emitting device 100, the size d and the pitch p may satisfy the relationship d/p≦0.3. Such a light-emitting device 100 can more efficiently illuminate an illumination target than a light-emitting device outside the above range (for details, see "Experimental Example" described later).

Although the GaN-based light-emitting element 20 that emits blue light has been described above, the light-emitting element can emit green light and red light by using semiconductor layers such as GaP-based and GaAs-based semiconductor layers. .

In the above description, the first semiconductor layer 22 is an n-type semiconductor layer and the second semiconductor layer 26 is a p-type semiconductor layer. Yes, the second semiconductor layer 26 may be an n-type semiconductor layer.

Although not shown, a heat sink may be provided on the +Z-axis direction side of the second electrode 32 . A heat sink may be adhered to the second electrode 32 . The material of the heat sink is copper, aluminum, or the like. The heat sink can efficiently dissipate the heat generated in the light emitting element 20 .

1.2. Method for Manufacturing Light Emitting Device Next, a method for manufacturing the light emitting device 100 according to the first embodiment will be described with reference to the drawings. 3A to 3D are cross-sectional views schematically showing manufacturing steps of the light emitting device 100 according to the first embodiment.

As shown in FIG. 3, the first semiconductor layer 22, the light emitting layer 24, and the second semiconductor layer 26 are epitaxially grown on the substrate 10 in this order. Examples of epitaxial growth methods include MOCVD (Metal Organic Chemical Vapor Deposition) and MBE (Molecular Beam Epitaxy).

As shown in FIG. 1, the second semiconductor layer 26, the light emitting layer 24, and the first semiconductor layer 22 are patterned to form a columnar portion 28. As shown in FIG. Patterning is performed, for example, by photolithography and etching.

Next, a first electrode 30 is formed on the first semiconductor layer 22 . The first electrode 30 is formed by, for example, a vacuum deposition method.

Next, an insulating layer 40 is formed on the semiconductor layers 22 and 26 and the first electrode 30 . The insulating layer 40 is formed by, for example, a spin coating method, a CVD (Chemical Vapor Deposition) method, or the like. The insulating layer 40 is then patterned to expose the second semiconductor layer 26 .

Next, a second electrode 32 is formed on the second semiconductor layer 26 and the insulating layer 40 . The second electrode 32 is formed by, for example, a vacuum deposition method.

Next, the lens array 52 is adhered to the bottom surface of the substrate 10, for example by an adhesive.

The light emitting device 100 can be manufactured through the above steps.

In the above description, the semiconductor layers 22 and 26 and the light-emitting layer 24 are epitaxially grown, and then the semiconductor layers 22 and 26 and the light-emitting layer 24 are patterned to form the columnar portion 28. First, the mask layer is formed. (not shown), and then, using the mask layer as a mask, the semiconductor layers 22 and 26 and the light emitting layer 24 may be epitaxially grown to form the columnar portion 28 .

2. Second Embodiment 2.1. Light Emitting Device Next, a light emitting device according to a second embodiment will be described with reference to the drawings. FIG. 4 is a cross-sectional view schematically showing a light emitting device 200 according to the second embodiment. FIG. 5 is a plan view schematically showing a light emitting device 200 according to the second embodiment. 4 is a sectional view taken along line IV-IV of FIG. 4 and 5, X-axis, Y-axis, and Z-axis are illustrated as three mutually orthogonal axes.

Hereinafter, in the light emitting device 200 according to the second embodiment, differences from the example of the light emitting device 100 according to the first embodiment described above will be described, and description of the same points will be omitted.

The light-emitting device 200 differs from the above-described light-emitting device 100 in that a drive circuit board 64 is provided between the substrate 60 and the light-emitting element 20, as shown in FIG. 4 and 5, the light emitting device 200 includes, for example, a substrate 60, a heat sink 62, a drive circuit substrate 64, an insulating layer 70, a first through via 80, a second through via 82, It has a pad 84 and a wiring 86 .

In the light emitting device 200, the substrate 60 is, for example, a silicon substrate.

A heat sink 62 is provided below the substrate 60 . The heat sink 62 is adhered to the bottom surface of the substrate 60, for example. The material of the heat sink 62 is copper, aluminum, or the like. The heat sink 62 can efficiently dissipate the heat generated in the light emitting element 20 .

A drive circuit board 64 is provided on the board 60 . A drive circuit for driving the light emitting element 20 is mounted on the drive circuit board 64 . The drive circuit is implemented by, for example, CMOS (Complementary Metal Oxide Semiconductor). The drive circuit can drive the light emitting element 20 based on, for example, input image information. Therefore, one light emitting element 20 can form one pixel. Light-emitting device 200 is, for example, a self-luminous imager.

The insulating layer 70 is provided on the drive circuit board 64 . The insulating layer 70 is, for example, a silicon oxide layer.

The first through via 80 and the second through via 82 are provided through the insulating layer 70 . The material of the through vias 80 and 82 is, for example, Ti. The first through via 80 connects the drive circuit mounted on the drive circuit board 64 and the second electrode 32 of the light emitting element 20 . The second through via 82 connects the drive circuit and the pad 84 .

A pad 84 is provided on the second through via 82 . The material of the pad 84 is, for example, metal.

The wiring 86 connects the pad 84 and the first electrode 30 of the light emitting element 20 . The material of the wiring 86 is, for example, metal.

The light emitting element 20 is provided on the first through via 80 and the insulating layer 70 . The plurality of light emitting elements 20 are separated from each other. In the illustrated example, the second electrode 32, the second semiconductor layer 26, the light emitting layer 24, the first semiconductor layer 22, and the first electrode 30 are arranged in this order from the first through via 80 side. The semiconductor layers 22 and 26, the light emitting layer 24, and the electrodes 30 and 32 have, for example, the same shape (square in the example shown in FIG. 5) in plan view.

The first electrode 30 is electrically connected to the driving circuit through the wiring 86, the pad 84, and the second through via 82. As shown in FIG. The material of the first electrode 30 is a transparent electrode such as ITO (Indium Tin Oxide). Light generated in the light emitting layer 24 passes through the first electrode 30 and enters the lens 50 .

The second electrode 32 is electrically connected to the driving circuit through the first through via 80 . For the second electrode 32, for example, an Al layer and a Ti layer are laminated in this order from the second semiconductor layer 26 side. By sufficiently smoothing and cleaning the Ti of the second electrode 32 and the Ti of the first through via 80 and applying pressure and heat, the second electrode 32 and the first through via 80 can be metal-bonded. can.

In the light-emitting device 200, the first electrode 30 and the second electrode 32 overlap the light-emitting layer 24 in plan view. In such a case, the second semiconductor layer 26 that forms the contact region 34 is the n-type semiconductor layer or the p-type semiconductor layer that has a smaller area of the contact region with the electrode. If the area of the contact region is the same, it is either one of the semiconductor layers. In the illustrated example, the second semiconductor layer 26 is a p-type semiconductor layer, and the area of the contact region 34 between the second semiconductor layer 26 and the second electrode 32 is the same as that of the first semiconductor layer 22 and the first electrode 30 . is the same as the area of the contact area of

In the light-emitting device 200 , the lens array 52 is provided on the +Z-axis direction side of the light-emitting element 20 . The lens array 52 is adhered, for example, to a supporting member (not shown).

2.2. Method for Manufacturing Light Emitting Device Next, a method for manufacturing the light emitting device 200 according to the second embodiment will be described with reference to the drawings.

Hereinafter, in the method for manufacturing the light emitting device 200 according to the second embodiment, differences from the example of the method for manufacturing the light emitting device 100 according to the first embodiment described above will be described, and the description of the same points will be omitted or simplified. .

As shown in FIG. 3, the first semiconductor layer 22, the light emitting layer 24, and the second semiconductor layer 26 are epitaxially grown on the substrate 10 in this order.

Substrate 10 is then removed by polishing and plasma etching. Next, as shown in FIG. 4, a first electrode 30 and a second electrode 32 are formed. The light emitting element 20 can be formed through the above steps. Note that the second electrode 32 may be formed before removing the substrate 10 .

Next, the substrate 60, the heat sink 62, the drive circuit board 64, the insulating layer 70, and the through vias 80 and 82 are prepared, and the light emitting element 20 is placed in the second direction with the second electrode 32 facing the first through via 80.
It is connected to the through via 82 .

A pad 84 is then formed on the second through via 82 . The pads 84 are formed by, for example, a sputtering method, a plating method, or the like. Note that the pad 84 may be formed before connecting the light emitting element 20 to the first through via 80 .

Next, the insulating layer 40 is formed on the first electrodes 30 and the pads 84 . The insulating layer 40 is then patterned to expose the first electrodes 30 and the pads 84 .

Next, wirings 86 are formed on the first electrodes 30 and the pads 84 . The wiring 86 is formed by, for example, a sputtering method, a plating method, or the like.

Next, the lens array 52 is arranged. The heat sink 62 may be adhered to the rear surface of the substrate 60 after the lens array 52 is arranged.

The light emitting device 200 can be manufactured through the above steps.

3. Third Embodiment 3.1. Light Emitting Device Next, a light emitting device according to a third embodiment will be described with reference to the drawings. FIG. 6 is a cross-sectional view schematically showing a light emitting device 300 according to the third embodiment. For convenience, members other than the light emitting element 20, the lens array 52, and the substrate 60 are omitted in FIG. Moreover, in FIG. 6, the light emitting element 20 is illustrated in a simplified manner. In addition, in FIG. 6 and FIGS. 7 and 8 described later, the X-axis, Y-axis, and Z-axis are illustrated as three mutually orthogonal axes.

Hereinafter, in the light-emitting device 300 according to the third embodiment, differences from the example of the light-emitting device 200 according to the second embodiment described above will be described, and description of the same points will be omitted.

In the light emitting device 300, as shown in FIG. 6, the shape of the lens 50 is different from that of the light emitting device 100 described above.

In the light-emitting device 300 , the light-emitting element 20 is provided on the substrate 60 . Among the plurality of light emitting elements 20 , the first light emitting element 20 a is adjacent to the second light emitting element 20 b among the plurality of light emitting elements 20 . The first lens 50a among the plurality of lenses 50 is a lens provided corresponding to the first light emitting element 20a. The second lens 50b among the plurality of lenses 50 is a lens provided corresponding to the second light emitting element 20b. The first lens 50a is adjacent to the second lens 50b. The light emitted from the first light emitting element 20a is not totally reflected by the first lens 50a and the second lens 50b.

For example, in the example shown in FIG. 7, the light ray L1 is a light ray that travels in the direction of the object to be illuminated (target direction) with a narrow radiation angle, and is projected onto the screen by the projection lens. The light ray L2 is a light ray that spreads in a direction different from the target direction and is not swallowed by the projection lens, so it does not affect the projection display. A light ray L3 is a light ray that repeats total reflection within the lens array 52 . A portion of the light beam L3 is scattered by the uneven structure formed by the light emitting element 20 or the like, resulting in crosstalk that dimly brightens a position unrelated to the display.

The light emitting device 300 shown in FIG. 6 can reduce crosstalk as described above. Note that FIG. 7 is a cross-sectional view schematically showing a light emitting device according to a reference example.

Here, FIG. 8 is an enlarged view of FIG. If n ₁ is the refractive index between the lens array 52 and the substrate 60, n ₂ is the refractive index of the lens array 52, and n ₃ is the refractive index of the outside (+Z-axis direction side) of the lens array 52, then n ₁ <n. ₂ > _n3 . _When the magnitude relationship between n1 and _n2 is reversed (n1> _n2 ), part of the light emitted from the light emitting element ₂₀ is totally reflected at the interface ₍ incident surface 51a) between n1 and _n2 . n ₁ <n ₂ . Air may be between the lens array 52 and the substrate 60 and outside the lens array 52 .

The second lens 50b is divided into a region A and a region B with a point C, which is the vertex of the exit surface 51b, as a boundary. At the point C, the exit surface 51b and the entrance surface 51a of the second lens 50b are parallel, so the traveling direction of the light passing through the point C is not bent by the second lens 50b. On the other hand, light passing through region A is bent in a narrowing direction, and light passing through region B is bent in a widening direction. The problem here is the light passing through the region B, which may undergo total internal reflection. In particular, the point D (the boundary between the first lens 50a and the _second lens 50b) is the point where the incident angle θ3 of light is the largest at the general radius of curvature R. If total reflection does not occur at point D, total reflection does not occur in the entire region B. FIG.

The conditions under which total reflection does not occur at point D are as follows. Let α be the tilt angle of the second lens 50b at the point D, and let θ ₁ and θ ₂ be the incident angles of light reaching the point D from the most +X-axis direction side of the first light emitting element 20a. Since it is (6), the following formula (7) can be derived.

The condition for total reflection at the point D is given by the following formula (8) according to Snell's law, and since θ ₃ =θ ₂ +α, the following formula (9) can be derived. Then, the following formula (10) can be derived from formulas (6) and (9).

If α is set so as to satisfy Equation (10), total reflection does not occur in the entire region B. θ ₁ is the distance d ₁ between the light emitting element 20 and the lens array 52, the thickness d ₂ of the lens array 52, the pitch of the light emitting element 20 and the lens 50 (the pitch of the light emitting unit 2) p, and the light emitting element It is determined by the size of 20 in plan view.

_In Equation ( ₁₀ ), the maximum value α _MAX of α was determined while changing d1 and d2, and the minimum value R _MIN of the radius of curvature R was determined from Equation (11) below.

9 and 10 are graphs showing the relationship between the distances d ₁ and d ₂ and the minimum value R _MIN of the radius of curvature R. FIG. 9 and 10, n ₁ =1 (air) and n ₃ =1 (air). Also, in FIG. 9, n ₂ =1.68 (high refractive index glass), and in FIG. 10, n ₂ =1.46 (quartz glass). 9 and 10, p=10 μm and the size of the LED (size in plan view) is 4 μm square.

9 and 10, in region H, _RMIN is 5 μm or more and less than 10 μm. In Region I, R _MIN is greater than or equal to 10 μm and less than 15 μm. In region J, R _MIN is 15 μm or more and less than 20 μm. In region K, R _MIN is greater than or equal to 20 μm and less than 25 μm. In region L, R _MIN is greater than or equal to 25 μm and less than 30 μm. In region M, R _MIN is greater than or equal to 30 μm and less than 35 μm. In region N, R _MIN is greater than or equal to 35 μm and less than 40 μm. In region O, R _MIN is greater than or equal to 40 μm and less than 45 μm. In region P, R _MIN is greater than or equal to 45 μm and less than 50 μm.

As shown in FIGS. 9 and 10, the larger the distances d ₁ and d ₂ were, the smaller the R _MIN was.

At each R _MIN above, there is no crosstalk to adjacent lenses. Also, the smaller the _radius of _curvature R, the higher the light collection efficiency and the higher the projection efficiency. Therefore, under the above conditions, projection efficiency was measured using a projection lens of F (F-number)=1.5. 11 and 12 are graphs showing the relationship between distances d ₁ and d ₂ and projection efficiency.

11 and 12, in region Q, the projection efficiency is 11.6% or more and less than 14.5%. In region S, the projection efficiency is 14.5% or more and less than 17.4%. In region T, the projection efficiency is 17.4% or more and less than 20.3%. In region U, the projection efficiency is 20.3% or more and less than 23.2%.

In FIGS. 11 and 12, since the contour lines of the projection efficiency generally run from the upper left to the lower right, it is assumed that the value of d ₁ +d ₂ can be discussed in a unified manner. FIG. 13 is a graph showing the relationship between d ₁ +d ₂ and projection efficiency in the case of FIG. 11 (n ₂ =1.68) and the case of FIG. 12 (n ₂ =1.46). The projection efficiency is the amount of light reaching an illumination target (for example, a screen) with respect to the amount of light emitted from the light emitting element 20 .

From _FIG . 13, regardless of the value of n2, the projection efficiency is high when d1 ₊ d2 is ₁₀ μm or more and 16 μm or less. This is the optimum value when p=10 μm, and since a geometric proportional relationship holds, it can be said that the optimum value of d ₁ +d ₂ is 1.0 times or more and 1.6 times or less of p. .

When d ₁ +d ₂ is increased, the minimum value R _MIN of the radius of curvature is decreased, the radiation angle of light is narrowed, and more light can be swallowed into the projection lens. However, if d ₁ +d ₂ is too large, the distance from the light emitting element 20 to the lens array 52 increases, and the amount of light that can be captured by the projection lens decreases. Therefore, d ₁ +d ₂ has an optimal value as above.

As shown in FIG. 8, when the distance between the lens array 52 and the point D is d3 _, and the size of the light emitting element 20 in plan view is w, the following formula (12) can be derived. Furthermore, the following formula (13) can be derived from the formula (6). Then, the following formula (14) can be derived from formulas (12) and (13).

In the light emitting device 300, the first light emitting element 20a among the plurality of light emitting elements 20 is adjacent to the second light emitting element 20b among the plurality of light emitting elements 20, and the light emitted from the first light emitting element 20a passes through the plurality of lenses. In the second lens 50b provided corresponding to the second light emitting element 20b, the light is not totally reflected. Therefore, in the light emitting device 300, crosstalk of light emitted from the light emitting element 20 can be reduced.

In addition, in the light-emitting devices 100 and 200 described above, the light emitted from the first light-emitting element 20a may not be totally reflected by the second lens 50b.

3.2. Method for Manufacturing Light Emitting Device Next, a method for manufacturing the light emitting device 300 according to the third embodiment will be described. The manufacturing method of the light emitting device 300 according to the third embodiment is basically the same as the manufacturing method of the light emitting device 200 according to the second embodiment described above. Therefore, detailed description thereof is omitted.

3.3. Modification of Light Emitting Device Next, a light emitting device according to a modification of the third embodiment will be described with reference to the drawings. FIG. 14 is a cross-sectional view schematically showing a light emitting device 310 according to the third embodiment. In addition, in FIG. 14 and FIGS. 15 to 18, which will be described later, the X-axis, Y-axis, and Z-axis are illustrated as the three mutually orthogonal axes.

Hereinafter, in the light-emitting device 310 according to the modification of the third embodiment, differences from the example of the light-emitting device 300 according to the third embodiment described above will be described, and description of the same points will be omitted.

In the light emitting device 300 described above, as shown in FIG. 6, the entrance surface 51a of the lens 50 is a flat surface, and the exit surface 51b is a curved surface. On the other hand, in the light emitting device 310, as shown in FIG. 14, both the entrance surface 51a and the exit surface 51b of the lens 50 are curved surfaces. In light emitting device 310, lens 50 is a biconvex lens.

In the light emitting device 310, for example, the light ray L3 (totally reflected light ray) shown in FIG. 6 can be removed. Among the plurality of lenses 50, the third lens 50c is a lens adjacent to the second lens 50b on the -X axis direction side of the second lens 50b. Among the plurality of light emitting elements 20, the third light emitting element 20c is a lens adjacent to the second light emitting element 20b on the -X axis direction side of the second light emitting element 20b. The third lens 50c is provided corresponding to the third light emitting element 20c.

Here, FIG. 15 is a cross-sectional view schematically showing the light emitting device according to the reference example. The light beam totally reflected by the third lens 50c is the light that hits the area E as shown in FIG.

A light ray emitted from the first light emitting element 20a and traveling along the incident surface 51a of the second lens 50b is refracted by the second lens 50b and travels as light ray L4, or refracted by the third lens 50c and travels as light ray L5. or either. In such a ray, there is geometrically no light traveling through region F to region E. Therefore, with the biconvex lens, the amount of light rays totally reflected by the third lens 50c is extremely small.

Light beams causing crosstalk in the biconvex lens as described above are light beams L6, L7, and L8. A light ray L6 is a light ray that is totally reflected by the first lens 50a. A light ray L7 is a light ray that is totally reflected by the second lens 50b. A light ray L8 is a light ray that is once emitted from the second lens 50b and then reenters the third lens 50c.

Since the light beams L6 and L7 are light beams incident on the region G of the first lens 50a, crosstalk can be reduced by adopting a structure in which the light beams are not geometrically incident on the region G. FIG.

In the light emitting device 310, as shown in FIG. 16, when a tangent line is drawn from the end of the light emitting element 20 on the -X axis side to the incident surface 51a of the first lens 50a, a region G can be secured outside the contact. defines the radius of curvature R ₁ , the distance d ₁ and the pitch p of the incident surface 51a.

On the other hand, the light ray L8 in FIG. 15 is re-entering the third lens 50c because it is bent too much by the second lens 50b. Therefore, it is effective to make the radius of curvature R2 of the output surface 51b smaller than the radius of curvature R1. Intuitively, it seems that the radius of curvature R2 should be increased, but since the light originally enters the lens 50 at a deep angle, it is correct to decrease the radius of curvature R2.

17 and 18 are cross-sectional views schematically showing the light emitting device 310. FIG. Note that FIG. 17 shows the case of R1=R2=80 μm. FIG. 18 shows the case of R1=80 μm and R2=70 μm.

In FIG. 17, the light ray L8 is re-entering the third lens 50c. On the other hand, in FIG. 18, the light ray L8 is not bent too much by the second lens 50b, so it does not re-enter the third lens 50c.

4. Fourth Embodiment 4.1. Projector Next, a projector according to a fourth embodiment will be described with reference to the drawings. FIG. 19 is a diagram schematically showing a projector 400 according to the fourth embodiment.

A projector according to the present invention has a light emitting device according to the present invention. A projector 400 having the light emitting device 100 as the light emitting device according to the present invention will be described below.

The projector 400 has a housing (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 housing. . Each of red light source 100R, green light source 100G, and blue light source 100B is light emitting device 100 . For the sake of convenience, FIG. 19 omits illustration of a housing that constitutes the projector 400 . Also, in FIG. 19, the light sources 100R, 100G, and 100B are illustrated in a simplified manner.

The projector 400 further includes transmissive liquid crystal light valves (light modulation devices) 402R, 402G, and 402B and a projection lens (projection device) 406 provided in the housing. The projector 400 is an LCD (Liquid Crystal Display) projector.

Light emitted from the light sources 100R, 100G, and 100B enters the liquid crystal light valves 402R, 402G, and 402B. Each of the liquid crystal light valves 402R, 402G, and 402B modulates incident light according to image information. A projection lens 406 magnifies the images (images) formed by the liquid crystal light valves 402 R, 402 G, and 402 B and projects them onto a screen (display surface) 408 . That is, the projection lens 406 projects the light emitted from the light sources 100R, 100G, and 100B onto the screen.

The projector 400 can also have a cross dichroic prism (color light combining means) 404 that combines the lights emitted from the liquid crystal light valves 402 R, 402 G, and 402 B and guides them to the projection lens 406 .

The three colored lights modulated by the liquid crystal light valves 402R, 402G, and 402B enter the cross dichroic prism 404. FIG. The cross dichroic prism 404 is formed by bonding four 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. These dielectric multilayer films synthesize three color lights to form light representing a color image. The combined light is projected onto a screen 408 by a projection lens 406, which is a projection optical system, to display an enlarged image.

4.2. Modified example of projector 4.2.1. First Modification Next, a projector according to a first modification of the fourth embodiment will be described with reference to the drawings. FIG. 20 is a cross-sectional view schematically showing a projector 410 according to the first modified example of the fourth embodiment. For convenience, FIG. 20 shows the light sources 100R, 100G, and 100B in a simplified manner. Also, in FIG. 20, illustration of the screen 408 is omitted.

Hereinafter, in the projector 410 according to the first modified example of the fourth embodiment, differences from the example of the projector 400 according to the fourth embodiment described above will be described, and description of the same points will be omitted. This is the same for a projector according to a second modification of the fourth embodiment, which will be described later.

In the projector 400 described above, as shown in FIG. 19, a transmissive liquid crystal light valve is used as the light modulation device. On the other hand, as shown in FIG. 20, the projector 410 uses a DMD (Digital Micromirror Device, registered trademark) 418 as an optical modulation device. The projector 410 is a DLP (Digital Light Processing, registered trademark) projector.

The projector 410 has light sources 100R, 100G, 100B, dichroic filters 411, 412, lenses 413, 414, 415, 416, a total internal reflection prism (TIR prism) 417, a DMD 418, and a projection lens 406. are doing.

Light emitted from the red light source 100 R is reflected by the dichroic filter 411 and enters the lens 413 . Light emitted from the green light source 100 G is reflected by the dichroic filter 412 , passes through the dichroic filter 411 , and enters the lens 413 . Light emitted from the blue light source 100B passes through the dichroic filters 411 and 412 and enters the lens 413 . Lights emitted from the light sources 100R, 100G, and 100B are synthesized in the dichroic filter 411. FIG.

The light emitted from lens 413 enters TIR prism 417 via lenses 414 , 415 and 416 . The lens 414 is a rod lens (integrator), and by repeating total reflection of light inside the lens 414, the illuminance distribution at the exit of the lens 414 can be made substantially uniform. Lenses 413, 415, and 416 are, for example, condensing lenses.

The light incident on the TIR prism 417 is reflected by the reflecting portion 417 a and enters the DMD 418 .

The DMD 418 modulates and reflects incident light according to image information. Light reflected by DMD 418 passes through TIR prism 417 and enters projection lens 406 .

4.2.2. Second Modification Next, a projector according to a second modification of the fourth embodiment will be described with reference to the drawings. FIG. 21 is a cross-sectional view schematically showing a projector 420 according to the second modified example of the fourth embodiment. For convenience, illustration of the screen 408 is omitted in FIG.

As shown in FIG. 19, the projector 400 described above has the light sources 100R, 100G, and 100B, which are the light emitting devices 100. As shown in FIG. On the other hand, the projector 420 has light sources 200R, 200G, and 200B, which are light emitting devices 200, as shown in FIG. Since the light-emitting device 200 is a self-luminous imager capable of forming pixels, the projector 420 does not have a separate light modulation device. Therefore, miniaturization can be achieved. For convenience, FIG. 21 shows the light sources 200R, 200G, and 200B in a simplified manner.

The red light source 200R, green light source 200G, and blue light source 200B emit red light, green light, and blue light, respectively. In addition, projector 420 has a Philips prism 422 .

Lights emitted from the light sources 200 R, 200 G, and 200 B are synthesized in the Philips prism 422 and enter the projection lens 406 . For example, the light emitted from the light sources 200R, 200G, and 200B is non-polarized light, so the Philips prism 422 that is less dependent on polarization is suitable.

In addition, the light emitting device according to the present invention can also be applied to apparatuses such as HMDs (head mounted displays) and HUDs (head up displays) to which projectors are applied. In addition to projectors, the light-emitting device according to the present invention can be widely applied to devices that require bright light with directivity, such as automobile headlights and spotlights.

5. Experimental Examples Experimental examples are shown below to describe the present invention more specifically. In addition, the present invention is not limited at all by the following experimental examples.

A model having a light emitting device corresponding to the light emitting device 100 and a projection lens of F=1.5 was simulated by Monte Carlo ray tracing. Note that FIG. 24 shown below is not a simulation but an experimental result obtained by actually manufacturing a light-emitting device and performing measurement.

The model light-emitting device used in the simulation has 100000 (100×100) light-emitting units (light-emitting units consisting of light-emitting elements (LEDs) and lenses) arranged in a matrix. In the model, the contact area between the second semiconductor layer and the second electrode (hereinafter also simply referred to as "contact area") is square.

FIG. 22 is a graph showing the relationship between the size of the contact area and projection efficiency. The pitch of the LEDs and the lenses (the pitch of the light emitting units) was set to 10 μm. Projection efficiency is the intensity of light reaching the screen relative to the intensity of light emitted from the LEDs.

As shown in FIG. 22, the projection efficiency was 40% or more when the size of the contact area was smaller than 4 μm square.

Next, FIG. 23 is a graph showing the relationship between the size of the contact area and the projected luminous flux (luminous flux projected onto the screen). In FIG. 23, when the contact area is 10 μm square without a microlens array (MLA) (that is, when the light-emitting layers of the LED are continuously arranged without gaps), the projected luminous flux is 100 is standardized as

As shown in FIG. 23, without MLA, the projected luminous flux decreased in proportion to the area of the contact area. On the other hand, in the case with MLA, even if the size of the contact area was 4 μm square, the projected luminous flux exceeding 90% could be maintained. For a contact area size of 4 μm square, the current injected into the emitting layer of the LED can be reduced by a factor of 6 to obtain the same brightness as without MLA.

Next, as an experiment corresponding to the light-emitting device 100 using an LED as the light-emitting element 20, the size of the contact area of the LED was variously changed, and its characteristics were measured. However, the shape of the contact area is square. Also, isolated LEDs were used instead of LEDs arranged in a matrix. FIG. 24 is a graph showing the relationship between the current density injected into the light emitting layer of the LED and the optical power density of the LED. The size of the contact area was changed from 100 μm square to 1 μm square.

As shown in FIG. 24, the optical power density tends to increase as the current density increases, but saturates at a certain current density. This is due to the droop phenomenon in which the luminous efficiency of the LED decreases when a large amount of power is supplied to the LED.

As shown in FIG. 24, a smaller contact area size can withstand higher optical power densities. It can be understood that this is because the smaller the size of the contact region, the lower the junction temperature due to heat dissipation from the side surface of the light emitting layer, and the quantum efficiency can be maintained. However, the effect of suppressing the droop phenomenon was saturated when the size of the contact area was 2 μm square. In addition, in the LED having a contact area smaller than 2 μm square, when patterning the light-emitting layer, the ratio of the light-emitting layer deteriorates due to the patterning, and the light emission intensity may decrease. Therefore, the size of the contact area is preferably 2 μm square or more.

Next, FIG. 25 is a graph showing the relationship between the contact area size, current density, and total current amount. In FIG. 25, "current density" indicates the limit current density at which the droop phenomenon occurs (the current density when the optical power density is maximized in FIG. 24). Also, in FIG. 25, the "total amount of current" is obtained by multiplying the current density by the size of the contact area.

As shown in FIG. 25, when the contact area was 10 μm square, the current density was as low as 2500 A/cm ² . This is because when the contact area is 10 μm square, adjacent contact areas are connected to form a 1 mm square contact area. When the contact area was 1 μm square, the current density could be increased to 28000 A/cm ² . When the contact area was 3 μm square or less, the total current amount became smaller than 25 A in the case of 10 μm square, and decreased to 3 A in the case of 1 μm square.

Next, FIG. 26 is a graph showing the relationship between the size of the contact area and the projected luminous flux when the current density is increased to the limit according to the size of the contact area as shown in FIG.

As shown in FIG. 26, with MLA, when the size of the contact area is 1 μm square or more and 9 μm square or less, the projected luminous flux becomes larger (brighter) than in the case of 10 μm square. In particular, when the size of the contact area was 4 μm square or more and 5 μm square or less, a projected light beam nearly ten times as large as that of 10 μm square was obtained. With MLA, the projected luminous flux was larger than without MLA.

Next, FIG. 27 is a graph showing the relationship between the size of the contact area and efficiency. In FIG. 27, "efficiency" is the projected luminous flux in FIG. 26 divided by the total current in FIG. As shown in Figure 27, the smaller the contact area, the higher the efficiency.

Next, FIG. 28 is a graph showing the relationship between the ratio (d/p) of the size (length of one side) d of the contact area to the pitch p of the LEDs and lenses and the projected luminous flux.

As shown in FIG. 28, when the ratio (d/p) was 0.4 or more and 0.5 or less, the projected luminous flux increased. Also, the smaller the pitch p, the higher the projected luminous flux, but the pitch was saturated at 12 μm. Therefore, it can be said that the pitch p is preferably 12 μm or less.

Next, FIG. 29 is a graph showing the relationship between the ratio (d/p) and efficiency. As shown in FIG. 29, when the pitch p was 5 μm or more and 12 μm or less, the ratio (d/p) had an inflection point of 0.5. It has been found that the ratio (d/p) is preferably 0.1 or more and 0.5 or less in order to improve the efficiency. In particular, the efficiency can be improved by setting the ratio (d/p) to 0.1 or more and 0.3 or less.

As described above, from FIG. 24, the size of the contact area is set to 2 μm square or more, from FIG. 28, the pitch p is set to 12 μm or less, and from FIG. can be efficiently illuminated.

The present invention may omit a part of the configuration or combine each embodiment and modifications as long as the features and effects described in the present application are provided.

The present invention includes configurations that are substantially the same as the configurations described in the embodiments (for example, configurations that have the same function, method, and result, or configurations that have the same purpose and effect). Moreover, the present invention includes configurations obtained by replacing non-essential portions of the configurations described in the embodiments. In addition, the present invention includes a configuration that achieves the same effects or achieves the same purpose as the configurations described in the embodiments. In addition, the present invention includes configurations obtained by adding known techniques to the configurations described in the embodiments.

2 Light-emitting unit 10 Substrate 20 Light-emitting element 20a First light-emitting element 20b Second light-emitting element 20c Third light-emitting element 22 First semiconductor layer 24 Light-emitting layer 26 Third 2 semiconductor layers 28 columnar portion 30 first electrode 32 second electrode 34 contact region 40 insulating layer 50 lens 50a first lens 50b second lens 50c second 3 lenses, 51a...incident surface, 51b...outgoing surface, 52...lens array, 60...substrate, 62...heat sink, 64...drive circuit board, 70...insulating layer, 80...first through via, 82...second through via , 84 Pad 86 Wiring 100 Light emitting device 100R Red light source 100G Green light source 100B Blue light source 200 Light emitting device 200R Red light source 200G Green light source 200B Blue light source 300 , 310... Light emitting device, 400... Projector, 402R, 402G, 402B... Liquid crystal light valve, 404... Cross dichroic prism, 406... Projection lens, 408... Screen, 410... Projector, 411, 412... Dichroic filter, 413, 414, 415, 416... lens, 417... TIR prism, 417a... reflector, 418... DMD, 420... projector, 422... Philips prism

Claims (7)

a first light emitting element;
a first lens provided corresponding to the first light emitting element;
a second light emitting element;
a second lens provided corresponding to the second light emitting element;
has
each of the first light emitting element and the second light emitting element,
a first semiconductor layer;
a second semiconductor layer having a conductivity type different from that of the first semiconductor layer;
a light-emitting layer provided between the first semiconductor layer and the second semiconductor layer and capable of generating light by current injection;
a first electrode electrically connected to the first semiconductor layer;
a second electrode in contact with the second semiconductor layer;
has
The second electrode overlaps the light-emitting layer in a plan view viewed from the stacking direction of the first semiconductor layer and the light-emitting layer,
wiring electrically connected to the first light emitting element is provided along a sidewall of the first light emitting element;
In a plan view viewed from the stacking direction, the wiring overlaps the end of the first lens and the end of the second lens between the first light emitting element and the second light emitting element,
In a plan view viewed from the stacking direction, the first light emitting element and the second light emitting element are provided at a pitch p in the first direction,
The size d in the first direction and the pitch p of the contact region between the second semiconductor layer and the second electrode are
d/p≦0.5 and p≦12 μm
satisfy the relationship of
A light-emitting device, wherein a part of the first electrode is arranged so as to surround the first semiconductor layer, the light-emitting layer, and the second semiconductor layer in plan view in the stacking direction . In claim 1 ,
The size d and the pitch p are
0.4≦d/p≦0.5
A light-emitting device that satisfies the relationship of In claim 1 ,
The size d and the pitch p are
d/p≦0.3
A light-emitting device that satisfies the relationship of In any one of claims 1 to 3 ,
the first light emitting element is adjacent to the second light emitting element,
The light-emitting device, wherein light emitted from the first light-emitting element is not totally reflected by the second lens. In any one of claims 1 to 4 ,
part of the first semiconductor layer, the light-emitting layer, and the second semiconductor layer constitute a columnar section;
the first electrode is provided in a portion of the first semiconductor layer that does not constitute the columnar portion;
The light-emitting device, wherein the first electrode is separated from the columnar portion in plan view in the stacking direction. In claim 5 ,
The light-emitting device, wherein the first electrode of the first light-emitting element and the first electrode of the second light-emitting element are continuous. A light emitting device according to any one of claims 1 to 6 ;
a projection device for projecting light emitted from the light emitting device;
a projector.

Images