Light-emitting device and display

Abstract

To provide a light-emitting device configured to emit polarized light having a proportion of a certain polarization component greater than a proportion of another polarization component by using the effect of near-field light.SOLUTION: A light-emitting device includes: at least one light-emitting element including a semiconductor layered portion and configured to emit light that has a predetermined wavelength and includes a first polarization component and a second polarization component; and at least one polarized light control member in contact with the at least one light-emitting element. The at least one polarized light control member includes a first structure and a second structure that are positioned in order from an at least one light-emitting element side. The first structure receives the light having the predetermined wavelength to generate near-field light. The second structure receives the near-field light and the light having the predetermined wavelength to emit light in which a proportion of the second polarization component is greater than a proportion of the first polarization component.SELECTED DRAWING: Figure 2A

Description

[Technical Field]

[0001] The present disclosure relates to light emitting devices and displays. [Background technology]

[0002] By using a polarizer, for example, it is possible to obtain unidirectionally polarized light from unpolarized light. Patent Document 1 discloses a polarization conversion plate that can convert unpolarized light into such polarized light by using near-field light. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2012-189651 Summary of the Invention [Problem to be solved by the invention]

[0004] There is a need for new light emitting devices that emit polarized light with a higher proportion of one polarization component than the other. [Means for solving the problem]

[0005] In one embodiment, the light emitting device of the present disclosure comprises at least one light emitting element including a semiconductor laminate portion and emitting light of a predetermined wavelength including a first polarization component and a second polarization component, and at least one polarization control member in contact with the at least one light emitting element, wherein the at least one polarization control member has, in order from the at least one light emitting element side, a first structure and a second structure, the first structure receives light of the predetermined wavelength to generate near-field light, and the second structure receives the near-field light and light of the predetermined wavelength to emit light in which the proportion of the second polarization component is greater than the proportion of the first polarization component.

[0006] Furthermore, a light-emitting device according to one embodiment of the present disclosure includes at least one light-emitting element including a semiconductor laminate and emitting light of a predetermined wavelength including a first polarization component and a second polarization component, and at least one polarization control member in contact with the light-emitting element. The polarization control member includes, in order from the light-emitting element side, a first structure and a second structure. The first structure and the second structure have a height length perpendicular to the light-emitting surface of the light-emitting element, a vertical length perpendicular to the height direction, and a horizontal length perpendicular to both the height direction and the vertical direction, which are shorter than a predetermined wavelength. The distance between the first structure and the second structure is shorter than the predetermined wavelength, and the ratio of the horizontal length to the vertical length of the second structure is greater than 1. [Effects of the Invention]

[0007] According to an embodiment of the present disclosure, a novel light emitting device can be provided that utilizes near-field light to emit polarized light in which the proportion of one polarization component is greater than the proportion of another polarization component. [Brief explanation of the drawings]

[0008] [Figure 1A] FIG. 1A is a perspective view schematically illustrating an example of the configuration of a light-emitting device according to an embodiment of the present disclosure. [Figure 1B] FIG. 1B is a top view schematically showing an example of the arrangement of three types of light-emitting elements included in the plurality of light-emitting elements shown in FIG. 1A. [Figure 1C] FIG. 1C is a top view schematically showing an example of the arrangement of three types of polarization control members included in the plurality of polarization control members shown in FIG. 1A. [Figure 1D] FIG. 1D is a side view, as viewed from the Y direction, that schematically shows how white polarized light is emitted from the light emitting device according to this embodiment. [Figure 2A] FIG. 2A is a perspective view schematically illustrating an example of a light emitting element and a polarization control member in this embodiment. [Figure 2B] FIG. 2B is a perspective view schematically illustrating a pair of the first structure and the second structure shown in FIG. 2A. [Figure 2C] FIG. 2C is a top view of the configuration shown in FIG. 2B. [Figure 3A] FIG. 3A is a perspective view schematically showing a pair of a first structure and a second structure. [Figure 3B] FIG. 3B is a top view of the configuration shown in FIG. 3A. [Figure 4A] FIG. 4A is a side view schematically showing Configuration Example 1 of the light emitting device according to this embodiment, as viewed from the Y direction. [Figure 4B] FIG. 4B is a side view schematically showing Configuration Example 2 of the light emitting device according to this embodiment, as viewed from the Y direction. [Figure 4C] FIG. 4C is a side view schematically showing Configuration Example 3 of the light emitting device according to this embodiment, as viewed from the Y direction. [Figure 4D] FIG. 4D is a side view, as viewed from the Y direction, that schematically shows Configuration Example 4 of the light emitting device according to this embodiment. [Figure 5A] FIG. 5A is a perspective view schematically illustrating a configuration example of a display according to this embodiment. [Figure 5B] FIG. 5B is an exploded perspective view of the display shown in FIG. 5A. [Figure 5C] FIG. 5C is a perspective view that schematically illustrates an example of the configuration of the virtual image display device according to this embodiment. [Figure 6A] FIG. 6A is a diagram for explaining an example of a step in the manufacturing method of the light emitting device according to this embodiment. [Figure 6B] FIG. 6B is a diagram for explaining an example of a step in the manufacturing method of the light emitting device according to this embodiment. [Figure 6C] FIG. 6C is a diagram for explaining an example of a step in the manufacturing method of the light emitting device according to this embodiment. [Figure 6D] FIG. 6D is a diagram for explaining an example of a step in the manufacturing method of the light emitting device according to this embodiment. [Figure 7A] FIG. 7A is a graph showing the energy conversion efficiency of the first and second polarized light components of transmitted light when unpolarized light is incident on the polarization control member in Calculation Example 1. [Figure 7B]FIG. 7B is a graph showing the energy conversion efficiency of the first and second polarized light components of transmitted light when unpolarized light is incident on the polarization control member in Calculation Example 2. [Figure 7C] FIG. 7C is a graph showing the energy conversion efficiency of the first and second polarized light components of transmitted light when unpolarized light is incident on the polarization control member in Calculation Example 3. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, light emitting devices according to embodiments of the present disclosure will be described in detail with reference to the drawings. Parts that appear in multiple drawings with the same reference numerals indicate the same or equivalent parts.

[0010] Furthermore, the following are examples to embody the technical ideas of the present disclosure and are not intended to limit the present disclosure. Furthermore, descriptions of the dimensions, materials, shapes, relative positions, etc. of components are intended for illustrative purposes only and are not intended to limit the scope of the present disclosure. The sizes and positional relationships of components shown in each drawing may be exaggerated to facilitate understanding.

[0011] In this specification and claims, when referring to polygons such as triangles and quadrilaterals, the term "polygon" also refers to shapes in which the corners (i.e., the ends of the sides) and / or the middle parts of the sides have been processed by rounding, chamfering, removing corners, rounding, etc.

[0012] In the drawings, for reference, mutually orthogonal X-axis, Y-axis, and Z-axis are shown. In this specification, the direction of the arrow of the Z-axis is referred to as "upward." This does not limit the orientation of the light emitting device when in use.

[0013] Furthermore, in this specification or claims, when there are multiple elements corresponding to a certain element and each element needs to be distinguished, the elements may be distinguished by adding "first" or "second" to the beginning of the element. If the objects or viewpoints distinguished between this specification and the claims are different, the same notation may not refer to the same object between this specification and the claims.

[0014] (Embodiment) A light emitting device according to one embodiment of the present disclosure includes at least one light emitting element including a semiconductor laminate and emitting light of a predetermined wavelength including a first polarization component and a second polarization component, and at least one polarization control member in contact with the light emitting element. The polarization control member includes, in order from the light emitting element side, a first structure and a second structure. The first structure receives light of the predetermined wavelength and generates near-field light. The second structure receives near-field light and light of the predetermined wavelength and emits light in which the proportion of the second polarization component is greater than the proportion of the first polarization component.

[0015] A light-emitting device according to an embodiment of the present disclosure includes at least one light-emitting element including a semiconductor laminate and emitting light of a predetermined wavelength including a first polarization component and a second polarization component, and at least one polarization control member in contact with the light-emitting element. The polarization control member includes, in order from the light-emitting element side, a first structure and a second structure. The first structure and the second structure have lengths in a height direction perpendicular to the light-emitting surface of the light-emitting element, a vertical direction perpendicular to the height direction, and a horizontal direction perpendicular to both the height direction and the vertical direction that are shorter than a predetermined wavelength. The distance between the first structure and the second structure is shorter than the predetermined wavelength, and the ratio of the horizontal length to the vertical length of the second structure is greater than 1. The light-emitting device according to the embodiment of the present disclosure configured as described above can emit light in which the proportion of the second polarization component is greater than the proportion of the first polarization component.

[0016] <Basic configuration example of a light-emitting device> First, with reference to FIGS. 1A to 1D, a basic configuration example of a light source device including multiple light-emitting devices according to an embodiment of the present disclosure will be described. The light-emitting device according to this embodiment uses near-field light to emit polarized light in which one of two orthogonal polarization components has a higher proportion than the other. In this embodiment, the light source device including multiple light-emitting devices can be, for example, a white backlight. The white backlight can be attached to, for example, a liquid crystal panel. The light-emitting device according to this embodiment is not limited to a white backlight, and can also be applied to, for example, a monochromatic polarized light source.

[0017] FIG. 1A is a perspective view schematically illustrating an example of the configuration of a light source device including a light-emitting device according to an embodiment of the present disclosure. The light-emitting device 100 shown in FIG. 1A includes light-emitting elements 10 having light-emitting surfaces 10s and polarization control members 20 in contact with the light-emitting surfaces 10s. Light emitted from the light-emitting surfaces 10s passes through the polarization control members 20 and is emitted to the outside. In this specification, "two objects in contact" refers not only to the case where the two objects are directly joined without a bonding material, but also to the case where a bonding material is present between the two objects. In the example shown in FIG. 1A, the height direction perpendicular to each light-emitting surface 10s is parallel to the Z direction, the vertical direction perpendicular to the height direction is parallel to the Y direction, and the horizontal direction perpendicular to both the height direction and the vertical direction is parallel to the X direction.

[0018] In the example shown in FIG. 1A, the plurality of light-emitting elements 10 are arranged periodically, but may be arranged irregularly. In this case, the polarization control members 20 that come into contact with the light-emitting surfaces 10s of the plurality of light-emitting elements 10 also become irregular. In the example shown in FIG. 1A, the plurality of light-emitting elements 10 and the plurality of polarization control members 20 are arranged at intervals, but they may also be arranged without gaps. In the example shown in FIG. 1A, the number of light-emitting elements 10 is 45, but it is sufficient that at least one light-emitting element 10 is arranged, for example, 10 2 10 pieces or more 5The number of polarization control members 20 may be on the order of 10 or less. The length of each light-emitting element 10 in the X direction is not particularly limited and may be, for example, 50 μm or more and 1 cm or less. The same applies to the length of each light-emitting element 10 in the Y direction. The lengths of each polarization control member 20 in the X direction and the Y direction are approximately equal to the lengths of each light-emitting element 10 in the X direction and the Y direction, respectively. Furthermore, the number of polarization control members 20 may be equal to the number of light-emitting elements 10. In the example shown in FIG. 1A, all of the multiple light-emitting surfaces 10s are flat surfaces parallel to the XY plane, but some or all of the light-emitting surfaces 10s may be curved surfaces.

[0019] The plurality of light-emitting elements 10 in this embodiment may include, for example, three types of light-emitting elements that respectively emit red light, green light, and blue light. The light emitted by each light-emitting element includes a first polarization component and a second polarization component that is orthogonal to the first polarization component, and is unpolarized overall. In this specification, "unpolarized" refers not only to a case where the energy of each of the two orthogonal polarization components is strictly 50% of the total energy, but also to a case where the energy of one polarization component is 49% or more but less than 50% of the total energy, and the energy of the other polarization component is the remainder of the total energy.

[0020] FIG. 1B is a top view schematically illustrating an example of the arrangement of three types of light-emitting elements included in the plurality of light-emitting elements 10 shown in FIG. 1A. In FIG. 1B, components other than the plurality of light-emitting elements 10 are omitted. Each row separated by a dashed line in FIG. 1B represents an arrangement of light-emitting elements emitting red, green, and blue light. The first row, represented by "R," is aligned along the Y direction and includes a plurality of first light-emitting elements 10a that emit unpolarized red light. Similarly, the second row, represented by "G," is aligned along the Y direction and includes a plurality of second light-emitting elements 10b that emit unpolarized green light. Similarly, the third row, represented by "B," is aligned along the Y direction and includes a plurality of third light-emitting elements 10c that emit unpolarized blue light. The first, second, and third rows are repeatedly aligned in this order along the X direction. In the example shown in FIG. 1B, the number of light-emitting elements aligned along the Y direction in each row is five. However, when used as a white backlight, the number may be, for example, 10 or more. 2 The order is as follows:

[0021] The multiple polarization control members 20 in this embodiment may include, for example, three types of polarization control members corresponding respectively to the three types of light-emitting elements. Fig. 1C is a top view schematically showing an example of the arrangement of the three types of polarization control members included in the multiple polarization control members 20 shown in Fig. 1A. Directly below the first polarization control member 20a, second polarization control member 20b, and third polarization control member 20c shown in Fig. 1C are located the first light-emitting element 10a, second light-emitting element 10b, and third light-emitting element 10c shown in Fig. 1B, respectively.

[0022] The first polarization control member 20a receives unpolarized light of a predetermined wavelength emitted from the first light-emitting element 10a and emits light of the predetermined wavelength in which the second polarization component is more abundant than the first polarization component. The same is true for the second polarization control member 20b and the third polarization control member 20c.

[0023] Each polarization control member is in contact with the light-emitting element directly below it, which allows each polarization control member to efficiently receive unpolarized light emitted from the light-emitting element directly below it and extract light in which the proportion of the second polarization component is higher than the proportion of the first polarization component from the unpolarized light.

[0024] Furthermore, each polarization control member is in contact with the light emitting element directly below it, so that the polarization control member can be made different for each element.

[0025] In the following description, "the proportion of the second polarization component is higher than the proportion of the first polarization component" means polarization in which, of two mutually orthogonal polarization directions, the energy in one polarization direction exceeds 50% of the energy of unpolarized light, and the energy in the other polarization direction is less than 50% of the energy of unpolarized light. The specific configurations of the first polarization control member 20a, the second polarization control member 20b, and the third polarization control member 20c will be described later.

[0026] As used herein, a "predetermined wavelength" refers to the wavelength between the shorter and longer of the two wavelengths at which the intensity of light emitted by each light-emitting element is half the intensity of the peak wavelength. For other wavelengths, the contribution of near-field light in the conversion of unpolarized light to polarized light is negligibly small. In this specification, red light may have a peak wavelength, for example, in the range of 605 nm to 750 nm, preferably in the range of 610 nm to 700 nm. Yellow light may have a peak wavelength, for example, in the range of 575 nm to less than 605 nm. Green light may have a peak wavelength, for example, in the range of 495 nm to less than 575 nm, preferably in the range of 510 nm to 550 nm. Blue light may have a peak wavelength, for example, in the range of 420 nm to less than 495 nm, preferably in the range of 440 nm to 475 nm. Purple light may have a peak wavelength, for example, in the range of 380 nm to less than 420 nm. The ultraviolet light may have a peak wavelength, for example, in the range of 200 nm or more and less than 380 nm. The difference between the longer and shorter wavelengths of the light emitted by each light-emitting element, i.e., the full width at half maximum, may be, for example, 10 nm or more and 50 nm or less. In this specification, the predetermined wavelengths of the light emitted from the first light-emitting element 10a, the second light-emitting element 10b, and the third light-emitting element 10c are also referred to as the "first wavelength," the "second wavelength," and the "third wavelength," respectively. These wavelengths are different from each other.

[0027] 1D is a side view, as viewed from the Y direction, schematically illustrating how white light 20L is emitted from the light source device according to this embodiment. For example, as shown in FIG. 1D, red light 20L is emitted from the first polarization control member 20a, the second polarization control member 20b, and the third polarization control member 20c. a , green light 20L b , and blue light 20L c The areas surrounded by the solid line, dashed line, and dashed line in FIG. 1D are the areas where the red light 20L is emitted. a , green light 20L b , and blue light 20L c The ratio of the second polarized component to the first polarized component of each light is greater than that of the first polarized component. Red light 20L a , green light 20L b , and blue light 20L c As each of the red light 20L travels in the Z direction, it spreads in the X direction. As a result, above the polarization control member 20, the red light 20L a , green light 20L b , and blue light 20L c It is possible to obtain white light 20L that is a mixture of the above. Local dimming may be achieved by dividing the light emitting device 100 according to this embodiment into a plurality of regions and adjusting the intensity of the white light 20L for each region.

[0028] The plurality of light-emitting elements 10 may include one type of light-emitting element that emits light having a predetermined wavelength, or may include multiple types of light-emitting elements that emit light having different predetermined wavelengths, depending on the application. The multiple types of light-emitting elements are not limited to three types of light-emitting elements, but may also include two types of light-emitting elements, or four or more types of light-emitting elements. The light emitted from one or multiple types of light-emitting elements does not necessarily have to be unpolarized.

[0029] <Specific configuration example of light emitting device> First, a light emitting device according to an embodiment of the present disclosure will be described with reference to Figures 2A to 2C. Figure 2A is a perspective view schematically illustrating an example of a light emitting element 10 and a polarization control member 20 according to this embodiment.

[0030] The light emitting device 100 shown in FIG. 2A includes a light emitting element 10 and a polarization control member 20 in contact with the light emitting element 10. The polarization control member 20 includes a first structure 22a and a second structure 22b. The light emitting element 10 emits light of a predetermined wavelength that includes a first polarization component and a second polarization component. A portion of the light passes through the first structure 22a, and another portion is incident on the first structure 22a to generate near-field light. The light that has passed through the first structure 22a and the near-field light generated by the first structure 22a act on the second structure, causing light to be emitted from the second structure 22b in which one polarization component is greater than the other polarization component compared to the light emitted from the light emitting element 10. Each component will be described below.

[0031] (Light-emitting element 10) The light-emitting element 10 includes a semiconductor laminate 12 and a light-transmitting member 14 and emits light of a predetermined wavelength including a first polarization component and a second polarization component. The light-emitting element 10 can be selected appropriately depending on the application, for example, from light-emitting elements that emit ultraviolet light, violet light, blue light, green light, yellow light, red light, or infrared light. The light-emitting element 10 can be configured using, for example, a III-V compound semiconductor and a silicon semiconductor. Examples of III-V compound semiconductors that can be used include nitride semiconductors, GaAs-based semiconductors, and InP-based semiconductors. The light-emitting element 10 can include a substrate and a semiconductor laminate provided on the substrate. The semiconductor laminate can include, in this order, an n-side semiconductor layer including an n-type semiconductor layer, an active layer, and a p-side semiconductor layer including a p-type semiconductor layer. When a silicon semiconductor is used, the light-emitting element can include, in this order, a silicon substrate including n-type impurities, an n-type silicon semiconductor layer including n-type impurities provided on the silicon substrate, and a p-type silicon semiconductor layer including p-type impurities. A pn junction is formed between the n-type semiconductor layer and the p-type semiconductor layer. The n-type impurity concentration of the silicon substrate is higher than the n-type impurity concentration of the n-type silicon semiconductor layer. Silicon can emit light using dressed photons and dressed photon phonons by performing dressed photon-assisted annealing. By appropriately selecting the wavelength of the laser light irradiated during dressed photon-phonon annealing, light with a wavelength corresponding to an energy smaller than the band gap energy of silicon can be emitted. The wavelength is, for example, 1300 nm or longer.

[0032] (Polarization control member 20) At least one polarization control member 20 contacts the light emitting element, thereby efficiently converting the light from the light emitting element into light in which the proportion of the second polarization component is greater than the proportion of the first polarization component.

[0033] The polarization control member 20 may include a plurality of first structures 22a and a plurality of second structures 22b. The polarization control member 20 may further include a dielectric layer 24 covering the side and top surfaces of the plurality of first structures 22a. In this case, the second structures 22b are disposed on the dielectric layer 24. The first structures 22a and the second structures 22b are aligned in this order along the Z direction from the light-emitting element 10 side. The first structures 22a and the second structures 22b may be paired in one-to-one correspondence. This allows light from the light-emitting element to be efficiently converted into the first polarization component or the second polarization component. The first structures 22a and the second structures 22b may be formed from at least one metal selected from the group consisting of Au, Al, Ag, and Cu, for example.

[0034] 2A, the arrangement pitch of the plurality of pairs of first structures 22a and second structures 22b in the X direction and the Y direction can be set arbitrarily. For example, the pitch of the first structures 22a and the second structures 22b is The wavelengths can be 530 nm or more and 800 nm or less in the Y direction and 320 nm or more and 480 nm or less in the Y direction. This reduces light absorption by the first structures and increases the efficiency of extracting the desired polarization component to the outside. In the example shown in FIG. 2A, the number of pairs of first structures 22a and second structures 22b included in the polarization control member 20 is 12, but this is not limited to this. The polarization control member 20 can be provided with an appropriate number of pairs so as to reduce light absorption by the first structures and extract the desired polarization component to the outside. Note that the multiple first structures 22a and the multiple second structures 22b do not necessarily need to be arranged periodically, but can be arranged irregularly. may be placed in

[0035] (Dielectric layer 24) The dielectric layer 24 covers the side and top surfaces of the first structure 22a and supports the second structure 22b via its top surface. The dielectric layer 24 can maintain the positional relationship between the first structure 22a and the second structure 22b in the Z direction. The dielectric layer 24 also contacts the light-emitting element 10 and holds the first structure 22a and the second structure 22b. The refractive index of the dielectric layer 24 can be smaller than the refractive index of the light-emitting element. The bandgap energy of the dielectric layer 24 can be higher than the energy corresponding to a predetermined wavelength of light emitted from the light-emitting element 10. This prevents the light emitted from the light-emitting element 10 from being absorbed by the dielectric layer 24. The dielectric layer 24 can be formed of, for example, SiO2, resin, gallium nitride, aluminum nitride, or aluminum oxide.

[0036] (First structure 22a and second structure 22b) Fig. 2B is a perspective view schematically showing a pair of first structure 22a and second structure 22b shown in Fig. 2A. Fig. 2C is a top view of the configuration shown in Fig. 2B. In Fig. 2B and Fig. 2C, illustration of components other than the pair of first structure 22a and second structure 22b is omitted.

[0037] As shown in FIG. 2B, the first structure 22a has a hollow square shape in the XY plane and a thickness in the Z direction. The hollow portion of the first structure 22a can efficiently transmit a portion of incident light, thereby reducing loss of incident light containing a desired polarization component due to absorption and / or reflection by the first structure 22a. As shown in FIG. 2C, the first structure 22a can have four-fold symmetry in the XY plane, with the center point of the hollow portion of the first structure 22a as the symmetry point. As shown in FIG. 2B, the second structure 22b includes a first portion 22b1 and a second portion 22b2 that are spaced apart along the Y direction in the XY plane. Each of the first portion 22b1 and the second portion 22b2 has a thickness in the Z direction. As shown in FIG. 2C, the longer protruding portions of the first portion 22b1 and the second portion 22b2 protrude in opposite directions along the X direction, and the shorter protruding portions protrude in opposite directions along the Y direction. As shown in Fig. 2C, second structure 22b can have two-fold symmetry in the XY plane with the center point of the hollow portion of first structure 22a as the symmetry point. As shown in Fig. 2C, first structure 22a and second structure 22b can have portions that overlap with each other when viewed from the Z direction, i.e., in a top view. Specifically, a portion of each of first portion 22b1 and second portion 22b2 included in second structure 22b overlaps a portion of first structure 22a in a top view.

[0038] The height length of the first structures 22a and the second structures 22b, which is perpendicular to the light-emitting surface 10s of the light-emitting element 10, the vertical length perpendicular to the height direction, and the horizontal length perpendicular to both the height direction and the vertical direction, are shorter than a predetermined wavelength, the distance between the first structures 22a and the second structures 22b is shorter than the predetermined wavelength, and the ratio of the horizontal length to the vertical length of the second structures 22b is greater than 1. That is, the maximum lengths in the X direction, Y direction, and Z direction of each of the first structures 22a and the second structures 22b included in the polarization control member 20 are all shorter than the predetermined wavelength of light emitted from the light-emitting element 10 corresponding to the polarization control member 20. Furthermore, the gap distance in the Z direction between the first structures 22a and the second structures 22b included in the polarization control member 20 is shorter than the predetermined wavelength of light emitted from the light-emitting element 10 corresponding to the polarization control member 20. In this specification, the gap distance between two objects is referred to as the "arrangement interval." The ratio of the maximum length in the Y direction of the second structure 22b to the maximum length in the X direction is greater than 1. This allows the second structure 22b to receive the near-field light generated by the first structure 22a and emit light having a desired polarization component. In the example shown in FIG. 2B, the maximum length in the Y direction of the second structure 22b is Length L of the first portion 22b1 in the Y direction b2 , the length L of the second portion 22b2 in the Y direction b2 , and the spacing between them d b is the sum of

[0039] (principle) The following briefly describes how a pair of first structural body 22a and second structural body 22b receives incident light and emits light of that kind.

[0040] First, the first structure 22a receives a portion of incident light of a predetermined wavelength that includes a first polarization component and a second polarization component, and generates near-field light.

[0041] The second structure 22b receives incident light that is irradiated without hitting the first structure 22a, incident light that has passed through and / or been scattered by the first structure 22a, and near-field light. These incident lights are hereinafter collectively referred to as propagating light.

[0042] The second structure 22b receives the propagating light, and based on an electric field caused by dielectric polarization that is generated, the second structure 22b emits a first light. The second light includes light that experiences a phase delay depending on the distance from the second structure 22b. Similarly, a second light is emitted from the second structure 22b based on dielectric polarization generated when the second structure 22b receives near-field light. Because the second light is caused by near-field light, it does not experience a phase delay like the first light. Meanwhile, the proportion of the first polarization component and the second polarization component contained in the second light varies depending on the shape and length of the first portion 22b1 and the second portion 22b2 included in the second structure 22b. The first polarization component and the second polarization component are defined as polarization components in the direction within the light-emitting plane. For example, the first polarization component is X-polarized light, and the second polarization component is Y-polarized light. Transmitted light, in which the first light and the second light are superimposed, is emitted from the second structure 22b in the Z direction. As shown in FIG. 2C, the length in the Y direction of the first portion 22b1 and the second portion 22b2 included in the second structure 22b is shorter than the length in the X direction, thereby increasing the proportion of the second polarization component in the near-field light. This makes it possible to make the proportion of the second polarized component in the transmitted light in which the first light and the second light are superimposed greater than the proportion of the first polarized component.

[0043] (Arrangement relationship between the first structure 22a and the second structure 22b) As described above, the second structure 22b receives the near-field light generated by the first structure 22a and the propagating light that has passed through the first structure 22a. Therefore, the arrangement interval between the first structure 22a and the second structure 22b in the Z direction is designed to be a distance that allows the near-field light generated by the first structure 22a to interact with the second structure 22b. Such a distance may be, for example, equal to or less than the wavelength of the incident light. For example, if the incident light is red light, it is 750 nm or less. Furthermore, if the incident light is green light, it is less than 575 nm. Furthermore, if the incident light is blue light, it is less than 495 nm. Note that if the arrangement interval between the first structure 22a and the second structure 22b deviates by ±50 nm from the predetermined interval, the transmittance of the second polarized light component may decrease by, for example, approximately 3%. Furthermore, in this case, the wavelength at which the transmittance of the second polarized light component is highest may vary by, for example, approximately ±5 nm. The near-field light generated by the first structure 22a interacts efficiently with the portions of the first portion 22b1 and the second portion 22b2 included in the second structure 22b that overlap with the first structure 22a in a top view. This is because the closer the distance between the first structure 22a and the second structure 22b is, the more the second structure 22b can receive the near-field light generated by the first structure 22a.

[0044] (Variation) 3A and 3B, a modified example of the polarization control member 20 will be described. Only the changes will be described.

[0045] FIG. 3A is a perspective view schematically showing a pair of first structure 22a and second structure 22b. FIG. 3B is a top view of the configuration shown in FIG. 3A. In FIGS. 3A and 3B, a pair of first structure 22a and second structure 22b is shown. Components other than the first structure 22a and the second structure 22b are omitted from the illustration. As shown in FIGS. 3A and 3B, the first structure 22a has a rectangular parallelepiped shape and does not have a hollow structure. Also, as shown in FIG. 3B, the first structure 22a and the second structure 22b do not overlap each other in a top view. Even with this configuration, by making the distance between the first structure 22a and the second structure 22b shorter than the length of a predetermined wavelength emitted by the light-emitting element, the near-field light generated in the first structure 22a can interact with the second structure 22b. Because no through-holes are provided in the first structure 22a, the first structure 22a can be easily fabricated.

[0046] The shapes of the first structure 22a and the second structure 22b are not limited to the examples described above. The first structure 22a may have, for example, a disk shape or a spherical shape. The first structure 22a does not necessarily have four-fold symmetry. The second structure 22b does not necessarily have multiple parts located apart, but may be a single structure. The second structure 22b does not necessarily have two-fold symmetry.

[0047] <Specific configuration example of light emitting device> Next, specific configuration examples 1 to 4 of the light emitting device 100 according to this embodiment will be described with reference to FIGS. 4A to 4D.

[0048] [Configuration example 1 of light-emitting device] FIG. 4A is a side view, as viewed from the Y direction, schematically illustrating a first configuration example of a plurality of light-emitting devices 100 according to this embodiment. The light-emitting device 100 includes a plurality of light-emitting elements 10 and a plurality of polarization control members 20. The plurality of light-emitting elements 10 include a first light-emitting element 10a that emits light of a first wavelength as a predetermined wavelength, a second light-emitting element 10b that emits light of a second wavelength as a predetermined wavelength, and a third light-emitting element 10c that emits light of a third wavelength as a predetermined wavelength. The first wavelength, the second wavelength, and the third wavelength are all different wavelengths. The plurality of polarization control members 20 include a first polarization control member 20a, a second polarization control member 20b, and a third polarization control member 20c. The first light-emitting element 10a includes a first semiconductor laminate 12a (denoted as "R" in FIG. 4A) that emits unpolarized red light of the first wavelength, and a first translucent member 14a provided on the first semiconductor laminate 12a. The second light-emitting element 10b includes a second semiconductor laminate 12b (indicated as "G" in FIG. 4A) that emits unpolarized green light of a second wavelength, and a second translucent member 14b provided on the second semiconductor laminate 12b. The third light-emitting element 10c includes a third semiconductor laminate 12c (indicated as "B" in FIG. 4A) that emits unpolarized blue light of a third wavelength, and a third translucent member 14c provided on the third semiconductor laminate 12c. The top surfaces of the first translucent member 14a, the second translucent member 14b, and the third translucent member 14c are respectively referred to as first light-emitting surfaces 10s. a , second light-emitting surface 10s b , and the third light-emitting surface 10s c The first light emitting element 10a to the third light emitting element 10c are so-called flip-chip type LEDs. In this specification, these light emitting elements are also referred to as "semiconductor light emitting elements."

[0049] Each of the first to third semiconductor laminates 12a to 12c includes, from top to bottom, an n-type semiconductor layer, an active layer, and a p-type semiconductor layer. The conductivity types may be reversed. A first electrode electrically connected to the p-type semiconductor layer and a second electrode electrically connected to the n-type semiconductor layer are provided on the bottom surface of each of the first to third semiconductor laminates 12a to 12c. Light is emitted from the active layer by applying a voltage between the first and second electrodes.

[0050] Regarding the first light-emitting element 10a, the second light-emitting element 10b, and the third light-emitting element 10c, The conductor laminated portion 12a, the second semiconductor laminated portion 12b, and the third semiconductor laminated portion 12c are, for example, G The first light-transmitting member 14a, the second light-transmitting member 14b, and the third light-transmitting member 14c are made of, for example, sapphire. In the example shown in FIG. 4A, the first semiconductor laminated portion 12a to the third semiconductor laminated portion 12b can be formed. 2c have the same thickness, but may have different thicknesses. Similarly, the first to third light-transmissive members 14a to 14c have the same thickness, but may have different thicknesses. Each of the first to third light-transmissive members 14a to 14c may include multiple portions formed from different light-transmissive materials.

[0051] The first light-transmissive member 14a is located between the first semiconductor laminate 12a and the first polarization control member 20a. The upper surface of the first light-transmissive member 14a contacts the lower surface of the first polarization control member 20a. Similarly, the second light-transmissive member 14b is located between the second semiconductor laminate 12b and the second polarization control member 20b. The upper surface of the second light-transmissive member 14b contacts the lower surface of the second polarization control member 20b. Similarly, the third light-transmissive member 14c is located between the third semiconductor laminate 12c and the third polarization control member 20c. The upper surface of the third light-transmissive member 14c contacts the lower surface of the third polarization control member 20c.

[0052] The refractive index of the first light-transmissive member 14a can be higher than that of the first semiconductor laminate 12a and lower than that of the first polarization control member 20a. Therefore, because the refractive index is intermediate, even if a portion of the light emitted from the first semiconductor laminate 12a is obliquely incident on the interface between the first semiconductor laminate 12a and the first light-transmissive member 14a and the interface between the first light-transmissive member 14a and the first polarization control member 20a, the proportion of the portion of the light that is totally reflected can be reduced, thereby improving the light extraction efficiency from the first light-emitting element 10a. The same applies to the relationship between the refractive indexes of the second semiconductor laminate 12b, the second light-transmissive member 14b, and the second polarization control member 20b. The same applies to the relationship between the refractive indexes of the third semiconductor laminate 12c, the third light-transmissive member 14c, and the third polarization control member 20c.

[0053] 4A, the light emitted from the first semiconductor laminate 12a passes through the first light-transmissive member 14a and the first polarization control member 20a, and can be emitted as light in which the proportion of the second polarization component is greater than the proportion of the first component. The same applies to the light emitted from the other semiconductor laminates.

[0054] At least one of the shape, size, and arrangement interval of the first structures and second structures included in the first polarization control member, second polarization control member, and third polarization control member varies according to the wavelength of light irradiated to each polarization control member. As a result, each polarization control member receives unpolarized light of a predetermined wavelength emitted from the corresponding semiconductor laminate, and efficiently converts a portion of the first polarization component into the second polarization component. This allows each light emitting device 100 to emit light in which the proportion of the second polarization component is greater than the proportion of the first polarization component.

[0055] 4A, due to the gaps between the first light-emitting element 10a to the third light-emitting element 10c, light emitted from each semiconductor laminate and incident on the side surface of each light-transmitting substrate while satisfying the condition of total reflection is reflected by the side surface and emitted from the upper surface of each light-transmitting substrate, thereby improving the light extraction efficiency from each light-emitting element.

[0056] [Configuration example 2 of light-emitting device] FIG. 4B is a side view, as viewed from the Y direction, schematically illustrating a second configuration example of the light-emitting device 100 according to this embodiment. The light-emitting device 100 includes at least one light-emitting element 10 and multiple polarization control members 20. The light-emitting element 10 includes a fourth semiconductor laminate 12d (indicated as "UV" in FIG. 4B) that emits violet or ultraviolet light, a first wavelength conversion member 16a (indicated as "R" in FIG. 4B) provided in a first region on the upper surface of the fourth semiconductor laminate 12d, a second wavelength conversion member 16b (indicated as "G" in FIG. 4B) provided in a second region on the upper surface of the fourth semiconductor laminate 12d, and a third wavelength conversion member 16c (indicated as "B" in FIG. 4B) provided in a third region on the upper surface of the fourth semiconductor laminate 12d. The multiple polarization control members 20 include the first polarization control member 20a, the second polarization control member 20b, and the third polarization control member 20c. The fourth semiconductor laminate portion 12d has an active layer including a barrier layer made of AlN or AlGaN and a barrier layer made of AlGaN or Ga The second wavelength conversion member 16b receives the violet or ultraviolet light and emits unpolarized green light of a second wavelength. The third wavelength conversion member 16c receives the violet or ultraviolet light and emits unpolarized blue light of a third wavelength. The first wavelength conversion member 16a, the second wavelength conversion member 16b, and the third wavelength conversion member 16c receive the violet or ultraviolet light and emits unpolarized blue light of a third wavelength. The top surfaces of the first wavelength conversion member 16a, the second wavelength conversion member 16b, and the third wavelength conversion member 16c are respectively referred to as first light-emitting surfaces 10s. a , second light-emitting surface 10s b , and the third light-emitting surface 10s c is.

[0057] Each of the first wavelength conversion member 16a to the third wavelength conversion member 16c is formed from a phosphor and a binder or a sintered body of the phosphor. The binder may be, for example, an inorganic material such as resin, aluminum oxide, or aluminum nitride. The first wavelength conversion member 16a may include a phosphor formed from a phosphor having a composition represented by, for example, K2SiF6:Mn (hereinafter, also referred to as "KSF phosphor"). The second wavelength conversion member 16b is, for example, Si 6-z Al z O z N 8-z :Eu(0 < z ≦ 4.2) (hereinafter, also referred to as "β-sialon phosphor") or a phosphor formed from AlN ceramics activated with Eu. The third wavelength conversion member 16c may include a phosphor formed from, for example, Ca 10 (PO4)6Cl2:Eu (hereinafter, also referred to as "CCA phosphor"). In the example shown in FIG.  4B, the first wavelength conversion member 16a to the third wavelength conversion member 16c have the same thickness, but may have different thicknesses.

[0058] The first wavelength conversion member 16a is located between the fourth semiconductor laminate portion 12d and the first polarization control member 20a. The upper surface of the first wavelength conversion member 16a contacts the lower surface of the first polarization control member 20a. Similarly, the second wavelength conversion member 16b is located between the fourth semiconductor laminate portion 12d and the second polarization control member 20b. The upper surface of the second wavelength conversion member 16b contacts the lower surface of the second polarization control member 20b. Similarly, the third wavelength conversion member 16c is located between the fourth semiconductor laminate portion 12d and the third polarization control member 20c. The upper surface of the third wavelength conversion member 16c contacts the lower surface of the third polarization control member 20c.

[0059] The gaps between the first wavelength conversion member 16a to the third wavelength conversion member 16c and the gaps between the first polarization control member 20a to the third polarization control member 20c may be provided as follows: The first wavelength conversion member 16a to the third wavelength conversion member 16c are formed without gaps on the fourth semiconductor laminate portion 12d, and the first polarization control member 20a to the third polarization control member 20c are formed without gaps on the first wavelength conversion member 16a to the third wavelength conversion member 16c, respectively. Then, grooves are formed to provide the gaps.

[0060] At least one of the shape, size, and arrangement interval of the first structures and second structures included in the first polarization control member, second polarization control member, and third polarization control member varies according to the wavelength of light irradiated to each polarization control member. As a result, each polarization control member receives unpolarized light emitted from its corresponding wavelength conversion member and efficiently converts a portion of the first polarization component into the second polarization component. This allows each light emitting device 100 to emit light in which the proportion of the second polarization component is greater than the proportion of the first polarization component.

[0061] [Configuration example 3 of light-emitting device] FIG. 4C is a side view, as viewed from the Y direction, that schematically illustrates a third configuration example of the light emitting device 100 according to this embodiment. The light emitting device 100 includes at least one light emitting element 10 and a plurality of polarization control members 20. The light emitting element 10 includes a fifth semiconductor laminate 12e (indicated as "B" in FIG. 4C) that emits unpolarized blue light, a fourth wavelength conversion member 16d (indicated as "R" in FIG. 4C) provided in a first region on the top surface of the fifth semiconductor laminate 12e, and a fourth wavelength conversion member 16b (indicated as "R" in FIG. 4C) of the fifth semiconductor laminate 12e. The fifth semiconductor laminate 12e includes a fifth wavelength conversion member 16e (indicated as "G" in FIG. 4C) provided in a second region on the upper surface and a fourth translucent member 14d provided in a third region on the upper surface of the fifth semiconductor laminate 12e. The multiple polarization control members 20 include a first polarization control member 20a, a second polarization control member 20b, and a third polarization control member 20c. The first polarization control member 20a contacts the fourth wavelength conversion member 16d. The second polarization control member 20b contacts the fifth wavelength conversion member 16e. The third polarization control member 20c contacts the fourth translucent member 14d. The fifth semiconductor laminate 12e is similar to that of Configuration Example 1 except that the active layer has a quantum well structure including barrier layers made of AlN, AlGaN, or GaN and well layers made of GaN or InGaN. Blue light, for example, is emitted from the active layer. The fourth wavelength conversion member 16d, the fifth wavelength conversion member 16e, and the fourth light-transmissive member 14d are irradiated with unpolarized blue light emitted from the common fifth semiconductor laminate portion 12e, and the fourth wavelength conversion member 16d receives the blue light and emits unpolarized red light of a first wavelength. The fifth wavelength conversion member 16e receives the blue light and emits unpolarized green light of a second wavelength. The fourth light-transmissive member 14d transmits unpolarized blue light of a third wavelength. The upper surfaces of the fourth wavelength conversion member 16d and the fifth wavelength conversion member 16e are respectively referred to as the first light-emitting surface 10s. a and second light-emitting surface 10s b The upper surface of the fourth light-transmissive member 14d is the third light-emitting surface 10s. c By providing the fourth light-transmissive member 14d, the height of the third polarization control member 20c can be aligned with that of the first polarization control member 20a and the second polarization control member 20b. As a result, the polarization control member 20 can be easily provided above the light-emitting element 10.

[0062] The fourth wavelength conversion member 16d may include a phosphor formed of, for example, KSF phosphor and a resin. The fifth wavelength conversion member 16e may include a phosphor formed of, for example, β-sialon phosphor and a resin. The fourth light-transmitting member 14d may be formed of, for example, sapphire, SiO2, or a resin.

[0063] As in the above-described configuration example 3, each light emitting device 100 can emit light in which the proportion of the second polarized component is greater than the proportion of the first polarized component.

[0064] [Configuration Example 4 of Light-Emitting Device] FIG. 4D is a side view, as viewed from the Y direction, schematically illustrating Configuration Example 4 of the light-emitting device 100 according to this embodiment. The light-emitting device 100 includes at least one light-emitting element 10 and multiple polarization control members 20. The light-emitting elements 10 include a common fifth semiconductor laminate 12e (denoted as "B" in FIG. 4D) that emits unpolarized blue light and a common sixth wavelength conversion member 16f (denoted as "R, G" in FIG. 4B) provided on the common fifth semiconductor laminate 12e. The multiple polarization control members 20 include a first polarization control member 20a, a second polarization control member 20b, and a third polarization control member 20c. The sixth wavelength conversion member 16f includes at least a first phosphor that receives blue light and emits red light of a first wavelength, and a second phosphor that receives blue light and emits green light of a second wavelength. The sixth wavelength conversion member 16f transmits unpolarized blue light of a third wavelength that has not been wavelength-converted by the first and second phosphors. The first phosphor may be, for example, a KSF phosphor, and the second phosphor may be, for example, β-sialon. The sixth wavelength conversion member 16f may further include a third phosphor that receives the blue light and emits unpolarized yellow light. The sixth wavelength conversion member 16f may be, for example, YAG (Yttrium Aluminum Oxide) phosphor. Garnet-based phosphors may be included. YAG-based phosphors include (Y,Gd)3(Al,Ga)5O 12 The sixth wavelength converting member 16f has an upper surface including a light emitting surface 10s. The light emitting elements 10 emit unpolarized blue light, unpolarized red light, and unpolarized green light from the light emitting surfaces 10s.

[0065] The sixth wavelength conversion member 16f is located between the fifth semiconductor laminate 12e and the first to third polarization control members 20a to 20c, and the upper surface of the sixth wavelength conversion member 16f contacts the lower surfaces of the first to third polarization control members 20a to 20c.

[0066] At least one of the shape, size, and arrangement interval of the first and second structures included in the first polarization control member 20a is determined so that the proportion of the second polarization component for red light can be efficiently increased compared to the proportion of the first polarization component. At least one of the shape, size, and arrangement interval of the first and second structures included in the second polarization control member 20b is determined so that the proportion of the second polarization component for green light can be efficiently increased compared to the proportion of the first polarization component. At least one of the shape, size, and arrangement interval of the first and second structures included in the third polarization control member 20c is determined so that the proportion of the second polarization component for blue light can be efficiently increased compared to the proportion of the first polarization component.

[0067] <Display configuration example> Next, a configuration example of a display according to this embodiment will be described with reference to Fig. 5A and Fig. 5B. Fig. 5A is a perspective view that schematically shows a configuration example of a display according to this embodiment. The display 200 shown in Fig. 5A includes a plurality of light-emitting devices 100 and a liquid crystal panel 30 provided on the plurality of light-emitting devices 100. A gap may be provided between the plurality of light-emitting devices 100 and the liquid crystal panel 30, or another member may be located between them. Fig. 5B is an exploded perspective view of the display shown in Fig. 5A.

[0068] As shown in FIG. 5B , the liquid crystal panel 30 of this embodiment includes, from the side of the plurality of light-emitting devices 100, a first polarizer 32a, a first translucent electrode 34a, a liquid crystal layer 36, a second translucent electrode 34b, a color filter 38, and a second polarizer 32b, in this order. The liquid crystal panel 30 may also include other components. The regions separated by vertical and horizontal dashed lines in FIG. 5B represent pixels. The pixel pitch may be, for example, 1 μm or more and 1 mm or less. The first polarizer 32a transmits light polarized in the Y direction (i.e., a direction parallel to the second polarization component), and the second polarizer 32b transmits light polarized in the X direction (i.e., a direction parallel to the first polarization component). The alignment direction of the liquid crystal material contained in the liquid crystal layer 36 is controlled by applying a voltage to the first translucent electrode 34a and the second translucent electrode 34b. This alignment control is performed for each pixel. The color filter 38 includes red, green, and blue filters for each pixel. Each polarization control member 20 is wider than one pixel in the XY plane. In the example shown in Fig. 5B, each polarization control member 20 substantially overlaps pixels arranged in three rows and three columns in top view. The rows and columns are parallel to the X and Y directions, respectively.

[0069] The bottom surface of the liquid crystal panel 30 is illuminated with white light emitted from the multiple light-emitting devices 100. This white light has a higher proportion of the second polarization component than the first polarization component. The white light is incident on a first polarizer 32a included in the liquid crystal panel 30. The first polarizer 32a transmits light polarized in the Y direction and absorbs light polarized in the X direction. A portion of the light polarized in the Y direction that passes through the first polarizer 32a may be converted into light polarized in the X direction via the liquid crystal layer 36 and transmitted through the second polarizer 32b. Light transmission and blocking can be controlled for each pixel by switching the voltage application on and off for each pixel.

[0070] The light emitting device 100 according to this embodiment can be used as a so-called direct-type backlight, as shown in Fig. 5A. This allows light in which the proportion of the second polarization component is greater than the proportion of the first polarization component to be effectively introduced into and transmitted through the liquid crystal, compared to so-called edge-type backlights, in a plurality of light emitting devices 100. Furthermore, by using the light emitting device 100 as a direct-type backlight, lighting control such as local dimming can be performed more precisely than with edge-type backlights, which is advantageous for high-definition display.

[0071] <Configuration example of virtual image display device> Next, with reference to FIG. 5C, a configuration example of a virtual image display device according to this embodiment will be described. FIG. 5C is a perspective view schematically illustrating a configuration example of a virtual image display device 300 according to this embodiment. The virtual image display device 300 shown in FIG. 5C includes a light-emitting device 100, an LCOS (Liquid Crystal on Silicon) 40, a collimating lens 50, and a light guide 60. The LCOS 40, the collimating lens 50, and the light guide 60 are located on the optical path of light emitted from at least one light-emitting device 100. The light guide 60 includes a light-guiding member 62 and an optical member 68. The light-guiding member 62 has a first reflecting portion 64 and a second reflecting portion 66, and the second reflecting portion 66 is the surface opposite the first reflecting portion 64. The two reflecting portions are arranged so that a plane including one reflecting portion intersects with another plane including the other reflecting portion. The arrows in FIG. 5C represent the path of light. Details of the components of the virtual image display device 300 other than the light emitting device 100 are disclosed in, for example, Japanese Patent Application Laid-Open No. 2021-9404.

[0072] Light emitted from at least one light-emitting device 100 passes through the LCOS 40, is collimated by the collimating lens 50, and enters the light guide 60. In the light guide 60, the incident light is reflected by the first reflecting portion 64, passes through the light-guiding member 62, is reflected by the second reflecting portion 66, and is then emitted from the light guide 60. The light emitted from the light guide 60 travels in the opposite direction to the light emitted from at least one light-emitting device 100 and enters the eyes of the user 70. As a result, the user 70 can view the image displayed on the LCOS 40. The optical member 68 has a tapered outer shape in a planar view and is disposed opposite the second reflecting portion 66 of the light-guiding member 62, thereby increasing the light transmittance of the second reflecting portion 66. The optical member 68 also transmits light coming from the direction of observation by the user 70. The optical member 68 aligns the viewing direction of the user 70 with the direction of the real image of the external world, thereby improving the visibility of the real image of the external world and the image displayed on the LCOS 40. In consideration of processability, the light guide member 62 is preferably molded from, for example, resin. The same applies to the optical member 68.

[0073] Specifically, the virtual image display device 300 can be used in a head-up display or a head-mounted display. In this use, a light-emitting diode can be used as the light-emitting element 10 included in at least one light-emitting device 100. Light-emitting diodes have smaller speckle noise than laser diodes, making the displayed image easier to view. Furthermore, even when at least one light-emitting device 100 according to this embodiment uses a light-emitting diode as the light-emitting element 10, the polarization control member 20 can emit light in which the proportion of the second polarization component is greater than the proportion of the first polarization component. As a result, the light emitted from the light-emitting element 10 efficiently passes through the LCOS 40, and an image can be displayed to the user 70 using the transmitted light.

[0074] <Method of manufacturing a light-emitting device> 6A to 6D, an example of a method for manufacturing the light emitting device 100 according to this embodiment will be described below. In the following description, the light emitting element 10 and polarization control member 20 included in the light emitting device 100 according to this embodiment will have the configuration example shown in FIG. 2A.

[0075] In the first step, as shown in Fig. 6A, a light-emitting element 10 is prepared, having a first metal thin film 22c formed on the light-emitting surface 10s of the light-emitting element 10. The first metal thin film 22c is formed on the light-emitting surface 10s of the light-emitting element 10 by, for example, sputtering or vacuum deposition. The first metal thin film 22c may be made of at least one metal selected from the group consisting of Au, Al, Ag, and Cu.

[0076] In the next step, as shown in FIG. 6B, the first metal thin film 22c is patterned using electron beam lithography to form a plurality of first structures 22a on the light-emitting surface 10s of the light-emitting element 10. An example of patterning is as follows. A resist is formed on the first metal thin film 22c, and unnecessary portions of the resist are removed by electron beam lithography. The portions of the first metal thin film 22c exposed by removing the resist are then removed by etching. Instead of using such an etching technique, patterning can also be performed using a lift-off method. Furthermore, as a patterning method using electron beam lithography, direct drawing without providing a resist can also be performed. Electron beam lithography can be performed using, for example, a variable rectangle drawing method or a partial block exposure method. The partial block exposure method is particularly preferable. In the partial block exposure method, the drawing time for a repeated pattern can be shortened by previously creating a pattern to be used repeatedly on a shaping aperture plate.

[0077] In the next step, as shown in FIG. 6C, a dielectric layer 24 is formed to cover the plurality of first structures 22a. The dielectric layer 24 is formed of, for example, SiO, resin, gallium nitride, aluminum nitride, or aluminum oxide. The dielectric layer 24 can be formed by, for example, sputtering, CVD, or the like.

[0078] 6D, a second metal thin film 22d is formed by sputtering on the dielectric layer 24. The material of the second metal thin film 22d is the same as that of the first metal thin film 22c.

[0079] In the next step, the second metal thin film 22d is patterned to form a plurality of second structures 22b on the dielectric layer 24, as shown in FIG. 2A.

[0080] Through the above steps, the light emitting device 100 according to this embodiment shown in FIG. 2A can be manufactured.

[0081] In the above manufacturing method, for the sake of simplicity, the explanation is given using drawings of the individualized state. Furthermore, after forming the light emitting element portion including the light emitting element portion and the polarization control member by the above manufacturing method, the light emitting element portion can be individualized to obtain a light emitting device including the light emitting element 10 and the polarization control member 20.

[0082] <Calculation example> 7A to 7C, calculation examples 1 to 3 are described below, which calculate the transmittance of the first and second polarization components when the polarization control member 20 converts unpolarized light into polarized light. The transmittance described in each calculation example is the square of the electric field of the first polarization component and the second polarization component, converted into the transmittance of light. The finite difference time domain (FDTD) method was used for the calculations.

[0083] [Calculation example 1] In calculation example 1, the following model was set. The polarization control member 20 has a plurality of pairs of first structures 22a and second structures 22b arranged two-dimensionally, with the first structure 22a and second structure 22b shown in FIG. 2B being one pair. Au was selected as the material for the first structures 22a and second structures 22b. For the first structure 22a, one side of a square is L a1 = 240 nm, and the length of one side of the square hollow part is La2 = 120 nm, and the thickness is t a For the second structure 22b, the long sides of the first portion 22b1 and the second portion 22b2 were L b1 = 150 nm, and the short side is L b2 = 120 nm, and the width of the longer protrusion is L b3 = 60 nm, and the width of the shorter protrusion is L b4 = 60 nm, and the thickness is t b The arrangement interval in the Y direction between the first portion 22b1 and the second portion 22b2 included in the second structure 22b was d b The arrangement distance between the first structural bodies 22a and the second structural bodies 22b in the Z direction was d ab =80n m. The arrangement pitch of the multiple sets of first structures 22a and second structures 22b in the X direction was 660 nm, and the arrangement pitch in the Y direction was 400 nm. Note that the dielectric layer 24 is not taken into consideration in the following calculation examples, including calculation example 1. This is because the influence of the dielectric layer 24 on the calculations is small.

[0084] The conditions for the FDTD calculation were a spatial cell size of 5 nm and a time step of 9.4 × 10 -18 The X and Y directions were periodic boundary conditions, and the Z direction was absorbing boundary conditions (PML: Perfectly Matched The number of PML layers was set to 10. The dielectric constant dispersion of the materials Au and Al was calculated based on the data in the book "Handbook This is taken from “The Complex Permittivity of Optical Constants of Solids” by Edward D. Palik. For example, the complex permittivity of Au at a wavelength of 652 nm is εr = 0.29, εi = 3.31.

[0085] [Calculation example 2] In the calculation example 2, the polarization control member 20 was modeled under the same conditions as in the calculation example 1, except for the following points, and calculations were performed. Al was selected as the material for the first structure 22a and the second structure 22b. For the first structure 22a, one side of a square was L a1= 160 nm, and the length of one side of the square hollow part is L a2 = 80 nm, and the thickness is t a For the second structure 22b, the long sides of the first portion 22b1 and the second portion 22b2 were L b1 = 100 nm, and the short side is L b2 = 80 nm, and the width of the longer protrusion is L b3 = 40 nm, and the width of the shorter protrusion is L b4 = 40 nm, and the thickness is t b The arrangement interval in the Y direction between the first portion 22b1 and the second portion 22b2 included in the second structure 22b was d b The arrangement distance between the first structures 22a and the second structures 22b in the Z direction was d ab The arrangement pitch of the plurality of sets of first structural bodies 22a and second structural bodies 22b in the X direction was 440 nm, and the arrangement pitch in the Y direction was 266 nm.

[0086] [Calculation example 3] The polarization control member 20 in Calculation Example 3 has a plurality of pairs of first structures 22a and second structures 22b, with the first structure 22a and second structure 22b shown in FIG. 3B being one pair. Calculation Example 3 differs from Calculation Example 1 in the shape of the first structures 22a. For the first structures 22a that do not have a hollow structure, one side of a square is L a = 20 nm, and the thickness is t a = 60 nm. Other materials and structural parameters in Calculation Example 3 were the same as those in Calculation Example 1.

[0087] [FDTD calculation] FIG. 7A is a graph showing the transmittance of the first and second polarization components of transmitted light when unpolarized light is incident on the polarization control member 20 in Calculation Example 1. The first polarization component is X-polarized light, and the second polarization component is Y-polarized light. This is similar to the other calculation examples, and these components will also be referred to as X-polarized light and Y-polarized light hereinafter. The solid line represents the transmittance of the Y-polarized component, and the dashed line represents the transmittance of the X-polarized component. The solid line in FIG. 7A takes into account the X-polarized light that is transmitted without being converted and the X-polarized light whose Y-polarized light has been converted. The dashed line in FIG. 7A also takes into account the Y-polarized light that is transmitted without being converted and the Y-polarized light whose X-polarized light has been converted. This also applies to the results of Calculation Examples 2 and 3, unless otherwise specified. The energy of each of the first and second polarization components of the incident unpolarized light is 50%. The horizontal dashed line in FIG. 7A indicates a transmittance of 50%. In the example shown in FIG. 7A, the calculation accuracy is low in the wavelength range of 350 nm or less, so the transmittance in this range is ignored.

[0088] As shown in Figure 7A, the transmittance of the transmitted X-polarized light was less than 40% in the wavelength range of 350 nm to 800 nm. In contrast, the transmittance of the transmitted Y-polarized light was greater than 50% in the wavelength range of 652 nm to 658 nm. It was suggested that the highest transmittance of Y-polarized light at a wavelength of 656 nm was 54%. At this time, it was suggested that the transmittance of X-polarized light at this wavelength was 26%. This means that of the light with a wavelength of 656 nm, 54% of the energy of the Y-polarized component is transmitted, and 26% of the X-polarized component is transmitted. In other words, this means that a portion of the X-polarized component is converted to a Y-polarized component, and the Y-polarized component becomes more abundant than the X-polarized component. Therefore, if the predetermined wavelength of the unpolarized light emitted from the light-emitting element 10 is 655 nm, it is thought that polarized light with the highest transmittance can be obtained from the polarization control member 20.

[0089] FIG. 7B is a graph showing the transmittance of X-polarized and Y-polarized transmitted light when unpolarized light is incident on polarization control member 20 in Calculation Example 2. In the example shown in FIG. 7B, the calculation accuracy is low in the wavelength range of 300 nm or less, so the transmittance in this range is ignored. As shown in FIG. 7B, the transmittance of X-polarized transmitted light was 40% or less in the wavelength range of 300 nm or more and 800 nm or less. In contrast, the transmittance of Y-polarized transmitted light exceeded 50% in the wavelength ranges of 376 nm or more and 426 nm or more and 435 nm or less. The maximum transmittance of Y-polarized transmitted light was 57% at a wavelength of 431 nm. In this case, the transmittance of X-polarized transmitted light was suggested to be 30%. This means that of the 431 nm light, 57% of the energy of the Y-polarized component was transmitted, and 30% of the X-polarized component was transmitted. In other words, a portion of the X-polarized component was converted to the Y-polarized component, resulting in a greater amount of Y-polarized component than the X-polarized component. It is believed that if the wavelength of the unpolarized light emitted from the light emitting element 10 is 430 nm, polarized light with the highest transmittance can be obtained.

[0090] FIG. 7C is a graph showing the transmittance of X-polarized and Y-polarized light transmitted through polarization control member 20 in Calculation Example 3 when unpolarized light is incident on polarization control member 20. As shown in FIG. 7C, the transmittance of X-polarized light transmitted through polarization control member 20 is less than 50% in the wavelength range of 350 nm to 950 nm. In contrast, the transmittance of Y-polarized light transmitted through polarization control member 20 is 52% at a wavelength of 660 nm, exceeding 50%. In this case, the transmittance of X-polarized light transmitted through polarization control member 20 is 34%. This means that, of the 660 nm light, 52% of the energy of the Y-polarized component is transmitted, and 34% of the X-polarized component is transmitted. In other words, a portion of the X-polarized component is converted to a Y-polarized component, resulting in a greater amount of Y-polarized light than the X-polarized component. It is believed that polarization with the highest transmittance can be obtained from polarization control member 20 if the wavelength of the unpolarized light emitted from light-emitting element 10 is 655 nm.

[0091] As explained in Calculation Examples 1 to 3, the wavelength at which the transmittance is highest depends on the material, shape, size, and arrangement interval in the Z direction of a pair of first structures 22 a and second structures 22 b. By appropriately designing these structural parameters, the wavelength at which the transmittance is highest can be made to coincide with a predetermined wavelength of light emitted from light-emitting element 10. [Industrial Applicability]

[0092] The light emitting device of the present disclosure can be applied to, for example, a white backlight for a liquid crystal panel, a polarized light source for a head-mounted display and a head-up display, or a monochromatic polarized light source. [Explanation of symbols]

[0093] 10 Light-emitting element 10a First light-emitting element 10b Second light-emitting element 10c Third light-emitting element 10s Light-emitting surface 10s a First light-emitting surface 10s b Second light-emitting surface 10s c Third light-emitting surface 12 Semiconductor laminate 12a First semiconductor laminate 12b Second semiconductor laminate 12c Third semiconductor stack 12d Fourth semiconductor laminate 12e Fifth semiconductor stack 14 Translucent material 14a First light-transmitting member 14b Second translucent member 14c Third translucent member 14d 4th translucent member 16a First wavelength conversion member 16b Second wavelength conversion member 16c Third wavelength conversion member 16d Fourth wavelength conversion member 16e Fifth wavelength conversion member 16f 6th wavelength conversion member 20 Polarization control member 20a First polarization control member 20b Second polarization control member 20c Third polarization control member 20L white light 20L a red light 20L b green light 20L c blue light 22a 1st structure 22b Second structure 22b1 Part 1 22b2 2nd part 30 LCD panel 32a 1st polarizing plate 32b 2nd polarizing plate 34a 1st translucent electrode 34b 2nd transparent electrode 36 Liquid crystal layer 38 Color Filter 40 LCOS 50 Collimating Lens 60 Light Guide 62 Light guide member 64 1st reflection section 66 2nd reflection section 68 Optical Components 100 Light-emitting device 200 displays 300 Virtual image display device

Claims

1. at least one light emitting element including a semiconductor laminate portion and emitting light of a predetermined wavelength including a first polarization component and a second polarization component; at least one polarization control member in contact with the at least one light emitting element; Equipped with the at least one polarization control member has, in order from the at least one light-emitting element side, a first structure and a second structure, the first structure receives light of the predetermined wavelength and generates near-field light; the second structure receives the near-field light and the light of the predetermined wavelength and emits light in which the proportion of the second polarization component is greater than the proportion of the first polarization component.

2. at least one light emitting element including a semiconductor laminate portion and emitting light of a predetermined wavelength including a first polarization component and a second polarization component; at least one polarization control member in contact with the at least one light emitting element; the at least one polarization control member has, in order from the light-emitting element side, a first structure and a second structure, a length of the first structure and the second structure in a height direction perpendicular to a light emitting surface of the light emitting element, a length in a vertical direction perpendicular to the height direction, and a length in a horizontal direction perpendicular to both the height direction and the vertical direction are shorter than the predetermined wavelength; a distance between the first structure and the second structure is shorter than the length of the predetermined wavelength; a ratio of the horizontal length to the vertical length of the second structure is greater than 1.

3. 3. The light emitting device according to claim 1, wherein the predetermined wavelength is equal to or greater than a shorter wavelength and equal to or less than a longer wavelength at which the intensity of the light emitted by the at least one light emitting element is half the intensity of the peak wavelength.

4. The light emitting device according to claim 1 , wherein the at least one polarization control member includes a dielectric layer covering a first structure, and the second structure is provided on the dielectric layer.

5. the at least one light emitting element includes a substrate; the substrate is located between the semiconductor laminate and the polarization control member, The light emitting device according to claim 4 , wherein the refractive index of the substrate is higher than the refractive index of the semiconductor laminate portion and lower than the refractive index of the dielectric layer.

6. The light emitting device according to claim 1 , wherein the first structure and the second structure included in the at least one polarization control member have portions that overlap with each other when viewed from above.

7. The light emitting device according to claim 1 , wherein the first structure and the second structure are made of metal.

8. The light emitting device according to claim 1 , wherein the at least one polarization control member comprises a first polarization control member and a second polarization control member.

9. The light emitting device according to claim 8 , wherein at least one of the shape, size, and arrangement interval of the first structures and the second structures is different between the first polarization control member and the second polarization control member.

10. the at least one light-emitting element further comprises at least one wavelength converting member; the at least one wavelength converting member is in contact with the at least one polarization controlling member; The light emitting device according to claim 1 , wherein the wavelength converting member receives light from the semiconductor laminate portion and emits light of the predetermined wavelength.

11. the at least one wavelength converting member includes a first wavelength converting member and a second wavelength converting member; the first wavelength conversion member is in contact with the first polarization control member, the second wavelength conversion member is in contact with the second polarization control member, the first wavelength conversion member receives light from the semiconductor laminate portion and emits light of a first wavelength as light of a predetermined wavelength, The light emitting device according to claim 10 , which cites claim 8 or 9 , wherein the second wavelength conversion member receives light from the semiconductor laminate portion and emits light of a second wavelength as the light of the predetermined wavelength.

12. the at least one polarization control member further comprises a third polarization control member; the at least one wavelength converting member further comprises a third wavelength converting member; the third wavelength conversion member is in contact with the third polarization control member, the third wavelength conversion member receives light from the semiconductor laminate portion and emits light having a third wavelength as the predetermined wavelength, The light emitting device of claim 11 , wherein the first wavelength, the second wavelength, and the third wavelength are all different wavelengths.

13. The at least one light emitting element is a first semiconductor light emitting element that emits light of a first wavelength as the light of the predetermined wavelength; a second semiconductor light emitting element that emits light of a second wavelength as the light of the predetermined wavelength; a third semiconductor light emitting element that emits light of a third wavelength as the light of the predetermined wavelength; Including, the at least one polarization control member further comprises a third polarization control member; the first polarization control member contacts the first semiconductor light emitting element; the second polarization control member contacts the second semiconductor light emitting element; the third polarization control member contacts the third semiconductor light emitting element; The light emitting device according to claim 8 , wherein the first wavelength, the second wavelength, and the third wavelength are all different wavelengths.

14. A display comprising the light-emitting device according to claim 1 and a liquid crystal panel.

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