JP2020106732A - projector - Google Patents

Abstract

To provide a projector that can reduce unevenness in brightness.SOLUTION: In a projector, when the maximum distance between an outer edge 16a of a first portion 14a and a center C of a light emitting part is A1, and the minimum distance between the center of an outer edge light emitting part of the first portion 14a and the center C is B1, the A1 and the B1 satisfy the relation of the following formula (1); when the maximum distance between an outer edge 16b of a second portion 14b and the center C is A2, and the minimum distance between the outer edge 16b of the second portion 14b and the center C is B2, the A2 and the B2 satisfy the relation of the following formula (2); when the maximum distance between an inner edge of the second portion 14b and the center C is A3, and the minimum distance between the inner edge of the second portion 14b and the center C is B3, the A3 and the B3 satisfy the relation of the following formula (3).SELECTED DRAWING: Figure 2

Description

The present invention relates to a projector.

A projector has been put into practical use, which illuminates a light modulation element such as a liquid crystal light valve with light emitted from a light source, and projects image light formed by the light modulation element onto a screen or the like by a projection lens for display.

In general, the light use efficiency of the projection lens is reduced in the peripheral portion away from the optical axis of the projection lens (peripheral light reduction). Therefore, even if light having a uniform intensity is emitted from the light source, the peripheral portion of the projected image projected on the screen becomes darker than the central portion.

For example, in Japanese Patent Application Laid-Open No. 2004-242242, the arrangement density of the emitters is increased in the darker peripheral region, the emission brightness itself of the corresponding display region is increased, and this is superposed with the influence of peripheral dimming. It is described that the luminance of the entire screen is uniform. Specifically, the area on the cathode substrate is divided into three areas from the center, and the density of the emitter is the lowest in the rectangular central area, followed by the middle rectangular annular area, and the outer rectangular annular area. Is the highest.

JP 2000-75406 A

However, in the projector described in Patent Document 1, the maximum distance between the outer edge of the rectangular central region and the center of the rectangular central region is set to A, and the outer edge of the rectangular central region and the rectangular edge When the minimum distance from the center of the central region is B, the ratio A/B is large. Therefore, when a projection lens that is circular when viewed from the optical axis direction is used, brightness unevenness occurs in the projection image projected on the screen.

One aspect of the projector according to the present invention is
A surface emitting light source having a light emitting portion,
Light emitted from the surface emitting light source, a light modulation element for modulating according to image information,
An image formed by the light modulation element is projected, and a projection lens that is circular when viewed from the optical axis direction,
Including
The light emitting unit has a plurality of portions having different amounts of light emission per unit area,
The plurality of portions have a larger amount of light emission per unit area as the portions are farther from the center of the light emitting portion when viewed in the light emission direction.
A first portion of the plurality of portions is disposed including the center,
A second portion of the plurality of portions is arranged adjacent to the first portion and surrounding the first portion when viewed from the emission direction,
Assuming that the maximum distance between the outer edge of the first portion and the center is A1 and the minimum distance between the outer edge of the first portion and the center is B1, as viewed from the emission direction, the A1 and the B1. Satisfies the relationship of the following formula (1),
Assuming that the maximum distance between the outer edge of the second portion and the center is A2 and the minimum distance between the outer edge of the second portion and the center is B2, the A2 and the B2 are expressed by the following formula (2). ) Relationship,
Assuming that the maximum distance between the inner edge of the second portion and the center is A3 and the minimum distance between the inner edge of the second portion and the center is B3, A3 and B3 are expressed by the following formula (3). ) Relationship,
The distance between the first position of the outer edge of the first portion and the center is A1;
The distance between the second position of the outer edge of the second portion and the center is A2,
The distance between the third position of the inner edge of the second portion and the center is A3,
The distance between the fourth position of the outer edge of the first portion and the center is B1,
The distance between the fifth position of the outer edge of the second portion and the center is B2,
The distance between the sixth position of the inner edge of the second portion and the center is B3,
The center, the first position, the second position, and the third position are on a straight line,
The center, the fourth position, the fifth position, and the sixth position are on a straight line.

In one aspect of the projector,
A third portion of the plurality of portions is arranged adjacent to the second portion and surrounding the second portion when viewed from the emission direction,
Assuming that the maximum distance between the outer edge of the third portion and the center is A4 and the minimum distance between the outer edge of the third portion and the center is B4 as viewed from the injection direction, the A4 and the B4 are the same. Satisfies the relationship of the following formula (4),
Assuming that the maximum distance between the inner edge of the third portion and the center is A5 and the minimum distance between the inner edge of the third portion and the center is B5, the A5 and the B5 are expressed by the following formula (5). ) Relationship,
The distance between the seventh position of the outer edge of the third portion and the center is A4,
The distance between the eighth position of the inner edge of the third portion and the center is A5,
The distance between the ninth position of the outer edge of the third portion and the center is B4,
The distance between the tenth position of the inner edge of the third portion and the center is B5,
The center, the first position, the seventh position, and the eighth position are on a straight line,
The center, the fourth position, the ninth position, and the tenth position may be on a straight line.

In one aspect of the projector,
The incident end surface of the projection lens has a convex shape in which the curvature increases as the distance from the optical axis increases,
The distance between the second position and the third position is smaller than the A1,
The distance between the fifth position and the sixth position may be smaller than B1.

In one aspect of the projector,
The surface emitting light source is
Board,
A laminate having a light emitting layer which is provided on the substrate and emits light;
Have
The stacked body may constitute a photonic crystal structure in which light emitted from the light emitting layer is confined in an in-plane direction of the substrate and emitted in a normal direction of the substrate.

In one aspect of the projector,
The light emitting unit may have a rectangular shape when viewed from the emission direction.

FIG. 3 is a diagram schematically showing the projector according to the first embodiment. FIG. 3 is a plan view schematically showing the surface emitting light source of the projector according to the first embodiment. FIG. 3 is a plan view schematically showing the surface emitting light source of the projector according to the first embodiment. FIG. 3 is a sectional view schematically showing the surface emitting light source of the projector according to the first embodiment. The top view which shows typically the surface emitting light source of the projector which concerns on the 1st modification of 1st Embodiment. The top view which shows typically the surface emitting light source of the projector which concerns on the 1st modification of 1st Embodiment. FIG. 9 is a plan view schematically showing a surface emitting light source of a projector according to a second modified example of the first embodiment. FIG. 9 is a plan view schematically showing a surface emitting light source of a projector according to a second modified example of the first embodiment. The side view which shows typically the incident end surface of the projection lens of the projector which concerns on the 2nd modification of 1st Embodiment. Sectional drawing which shows typically the surface emitting light source of the projector which concerns on the 3rd modification of 1st Embodiment. FIG. 8 is a diagram schematically showing a projector according to a fourth modified example of the first embodiment. FIG. 8 is a diagram schematically showing a projector according to a fourth modified example of the first embodiment. The figure which shows the projector which concerns on 2nd Embodiment typically. The figure which shows the projector which concerns on 3rd Embodiment typically.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. It should be noted that the embodiments described below do not unduly limit the content of the invention described in the claims. In addition, not all of the configurations described below are essential configuration requirements of the invention.

1. 1. First Embodiment 1.1. Projector First, the projector according to the first embodiment will be described with reference to the drawings. FIG. 1 is a diagram schematically showing a projector 100 according to the first embodiment.

As shown in FIG. 1, the projector 100 includes, for example, surface emitting light sources 10R, 10G, and 10B, a concave lens 20, a convex lens 22, a first polarization element 30, a second polarization element 32, and a light modulation element 40. , A color light combining prism 50 and a projection lens 60.

The surface emitting light source 10R emits red light. The surface emitting light source 10G emits green light. The surface emitting light source 10B emits blue light. In the illustrated example, a radiation fin 70 is arranged on one surface of each of the surface emitting light sources 10R, 10G, and 10B. The radiating fins 70 radiate the heat generated by the surface emitting light sources 10R, 10G and 10B. Thereby, the luminous efficiency of surface emitting light sources 10R, 10G, and 10B can be improved.

Each of the lights emitted from the surface emitting light sources 10R, 10G, and 10B has its luminous flux diameter enlarged by a Galilean-type magnifying illumination system including a concave lens 20 and a convex lens 22, and enters the light modulation element 40. In the Galileo-type magnifying illumination system, the total length of the illumination system can be shortened, and light with extremely high intensity can be handled.

The light modulation element 40 modulates the light emitted from the surface emitting light sources 10R, 10G, and 10B according to image information. Three light modulation elements 40 are provided corresponding to the surface emitting light sources 10R, 10G, and 10B. The light modulator 40 is, for example, a transmissive liquid crystal light valve that transmits the light emitted from the surface emitting light sources 10R, 10G, and 10B. The projector 100 is an LCD (liquid crystal display) projector.

The first polarization element 30 is provided on the incident side of the light modulation element 40. The first polarizing element 30 adjusts the polarization direction and the polarization degree of the light emitted from the surface emitting light sources 10R, 10G, and 10B. Specifically, the first polarizing element 30 is an optical element that transmits only linearly polarized light in a specific direction. The first polarizing element 30 can align the polarization directions of the light emitted from the surface emitting light sources 10R, 10G, and 10B.

The second polarization element 32 is provided on the exit side of the light modulation element 40. The second polarizing element 32 functions as an analyzer for the light emitted from the surface emitting light sources 10R, 10G, 10B. The light emitted from the second polarizing element 32 enters the color light combining prism 50.

The color light combining prism 50 emits light emitted from the surface emitting light source 10R and transmitted through the light modulation element 40, light emitted from the surface emitting light source 10G passing through the light modulation element 40, and light emitted from the surface emission light source 10B. The light transmitted through the modulation element 40 is combined. The color light combining prism 50 is formed, for example, by laminating four right-angle prisms, and has a dielectric multilayer film that reflects red light and a dielectric multilayer film that reflects blue light arranged in a cross shape on the inner surface thereof. It is a dichroic prism.

The projection lens 60 projects the light combined by the color light combining prism 50, that is, the image light formed by the light modulation element 40, onto a screen (not shown). An enlarged image is displayed on the screen. The projection lens 60 is circular when viewed from the optical axis direction, and its optical characteristics have rotational symmetry about the optical axis.

Here, FIG. 2 is a plan view schematically showing the surface emitting light source 10R. FIG. 3 is an enlarged view of FIG. FIG. 4 is a sectional view taken along the line IV-IV in FIG. 2 schematically showing the surface emitting light source 10R. Note that, for convenience, in FIG. 2, the surface emitting light source 10R is simplified and the light emitting unit 12 is illustrated. Further, in FIG. 3, members other than the light emitting unit 12 are not shown.

As shown in FIG. 4, the surface emitting light source 10R includes, for example, a substrate 102, a stacked body 103 provided on the substrate 102, a first electrode 122, and a second electrode 124. The stacked body 103 includes a reflective layer 104, a buffer layer 106, a photonic crystal structure 108, and a semiconductor layer 120.

The substrate 102 is, for example, a Si substrate, a GaN substrate, a sapphire substrate, or the like.

The reflective layer 104 is provided on the substrate 102. The reflective layer 104 is, for example, a DBR (distribution Bragg reflector) layer. The reflection layer 104 is, for example, a layer in which an AlGaN layer and a GaN layer are alternately laminated, a layer in which an AlInN layer and a GaN layer are alternately laminated, and the like. The reflective layer 104 reflects the light generated in the light emitting layer 114 of the columnar section 110 of the photonic crystal structure 108 toward the second electrode 124 side.

Note that “upper” means a direction away from the substrate 102 when viewed from the light emitting layer 114 in a stacking direction of the semiconductor layer 112 and the light emitting layer 114 of the columnar section 110 (hereinafter, also simply referred to as “stacking direction”). “Down” means a direction closer to the substrate 102 when viewed from the light emitting layer 114 in the stacking direction.

The buffer layer 106 is provided on the reflective layer 104. The buffer layer 106 is a layer made of a semiconductor, and is, for example, an Si-doped n-type GaN layer. In the illustrated example, a mask layer 128 for growing the columnar section 110 is provided on the buffer layer 106. The mask layer 128 is, for example, a silicon oxide layer, a silicon nitride layer, or the like.

The photonic crystal structure 108 is provided on the buffer layer 106. The photonic crystal structure 108 has a columnar section 110 and a light propagation layer 118. The stacked body 103 constitutes a photonic crystal structure 108. In the illustrated example, the columnar section 110 and the light propagation layer 118 of the stacked body 103 form a photonic crystal structure 108.

The photonic crystal structure 108 can exhibit the effect of a photonic crystal, confine light emitted by the light emitting layer 114 of the photonic crystal structure 108 in the in-plane direction of the substrate 102, and in the normal direction of the substrate 102. Inject it into. Here, the “in-plane direction of the substrate 102” is a direction orthogonal to the stacking direction. The “normal direction of the substrate 102” is the stacking direction. The surface emitting light source 10R is a photonic crystal laser having a photonic crystal structure 108.

The columnar section 110 is provided on the buffer layer 106. The planar shape of the columnar portion 110 is a polygon such as a regular hexagon, a circle, or the like. The diameter of the columnar portion 110 is, for example, on the order of nm, and specifically 10 nm or more and 500 nm or less. The size of the columnar section 110 in the stacking direction is, for example, 0.1 μm or more and 5 μm or less.

Note that the “diameter” is a diameter when the columnar section 110 has a circular planar shape, and when the columnar section 110 has a polygonal planar shape, it is the smallest circle that contains the polygon, that is, the smallest circle. The diameter of the included circle. Further, the “planar shape” is a shape viewed from the stacking direction.

A plurality of columnar parts 110 are provided. The distance between the adjacent columnar portions 110 is, for example, 1 nm or more and 500 nm or less. The columnar parts 110 are periodically arranged in a predetermined direction at a predetermined pitch. The plurality of columnar portions 110 are arranged, for example, in a triangular lattice shape, a square lattice shape, or the like when viewed from the stacking direction.

The columnar section 110 has a semiconductor layer 112, a light emitting layer 114, and a semiconductor layer 116.

The semiconductor layer 112 is provided on the buffer layer 106. The semiconductor layer 112 is, for example, a Si-doped n-type GaN layer.

The light emitting layer 114 is provided on the semiconductor layer 112. The light emitting layer 114 is the semiconductor layer 11
2 and the semiconductor layer 116. The light emitting layer 114 has a quantum well structure composed of, for example, a GaN layer and an InGaN layer. The light emitting layer 114 is a layer capable of emitting light when a current is injected.

The semiconductor layer 116 is provided on the light emitting layer 114. The semiconductor layer 116 is a layer having a conductivity type different from that of the semiconductor layer 112. The semiconductor layer 116 is, for example, a Mg-doped p-type GaN layer. The semiconductor layers 112 and 116 are clad layers having a function of confining light in the light emitting layer 114.

The light propagation layer 118 is provided between the adjacent columnar parts 110. In the illustrated example, the light propagation layer 118 is provided on the mask layer 128. The refractive index of the light propagation layer 118 is lower than the refractive index of the light emitting layer 114, for example. The light propagation layer 118 is, for example, a silicon oxide layer, an aluminum oxide layer, a titanium oxide layer, or the like. The light generated in the light emitting layer 114 can propagate in the light propagation layer 118.

In the surface-emitting light source 10R, the p-type semiconductor layer 116, the light-emitting layer 114 not doped with impurities, and the n-type semiconductor layer 112 form a pin diode. The semiconductor layers 112 and 116 are layers having a band gap larger than that of the light emitting layer 114. In the surface emitting light source 10R, when a forward bias voltage of a pin diode is applied between the first electrode 122 and the second electrode 124 to inject a current, electrons and holes are recombined in the light emitting layer 114. Luminescence is generated by this recombination. The light generated in the light emitting layer 114 propagates in the in-plane direction of the substrate 102 through the light propagation layer 118 by the semiconductor layers 112 and 116, and a standing wave is generated by the photonic crystal effect of the photonic crystal structure 108. Formed and confined in the in-plane direction of the substrate 102. The confined light receives a gain in the light emitting layer 114 and lases. That is, the light generated in the light emitting layer 114 resonates in the in-plane direction of the substrate 102 by the photonic crystal structure 108, and laser oscillation occurs. Then, the +1st-order diffracted light and the -1st-order diffracted light travel as laser light in the stacking direction.

Of the laser light that travels in the stacking direction, the laser light that travels toward the reflective layer 104 is reflected by the reflective layer 104 and travels toward the second electrode 124. Accordingly, the surface emitting light source 10R can emit light from the second electrode 124 side.

The emission angle of the light emitted from the surface emitting light source 10R is less than 2°, which is smaller than, for example, an end face type semiconductor laser or a VCSEL (Vertical Cavity Surface Emitting Laser). Further, for example, even if one columnar portion 110 has a defect, a standing wave is formed in a direction orthogonal to the stacking direction, so that the defect can be compensated and light with high intensity uniformity can be emitted.

The semiconductor layer 120 is provided on the photonic crystal structure 108. The semiconductor layer 120 is, for example, a p-type GaN layer doped with Mg.

The first electrode 122 is provided on the buffer layer 106. The buffer layer 106 may be in ohmic contact with the first electrode 122. In the illustrated example, the first electrode 122 is electrically connected to the semiconductor layer 112 via the buffer layer 106. The first electrode 122 is one electrode for injecting a current into the light emitting layer 114. As the first electrode 122, for example, a layer in which a Ti layer, an Al layer, and an Au layer are stacked in this order from the buffer layer 106 side is used.

The second electrode 124 is provided on the semiconductor layer 120. The semiconductor layer 120 may be in ohmic contact with the second electrode 124. The second electrode 124 is electrically connected to the semiconductor layer 116. In the illustrated example, the second electrode 124 is electrically connected to the semiconductor layer 116 via the semiconductor layer 120. The second electrode 124 is the other electrode for injecting a current into the light emitting layer 114. As the second electrode 124, for example, ITO (Indium Tin Oxide) is used.

The surface emitting light source 10R has a light emitting unit 12, as shown in FIGS. The light emitting unit 12 is a portion that emits light. When the surface-emitting light source 10R is a photonic crystal laser including the columnar section 110 having the light emitting layer 114, the light emitting section 12 is the photonic crystal structure 108. In the example shown in FIG. 2, the light emitting unit 12 has a rectangular shape when viewed from the light emission direction. The planar shape of the light emitting unit 12 may be similar to the shape of the illuminated surface of the light modulation element 40. Thereby, high illumination efficiency can be obtained. The “light emission direction” is the stacking direction.

The light emitting unit 12 has, for example, a plurality of portions 14a, 14b, 14c, 14d, 14e, and 14f having different light emission amounts per unit area when viewed from the stacking direction. The plurality of portions 14a, 14b, 14c, 14d, 14e, 14f are classified according to the amount of injected current. In the illustrated example, the portions 14a, 14b, 14c, 14d, 14e, and 14f depend on the amount of current injected into the light emitting layer 114 of the columnar portion 110 included in each of the portions 14a, 14b, 14c, 14d, 14e, and 14f. Be divided. In each of the plurality of portions 14a, 14b, 14c, 14d, 14e, 14f, the amount of current injected into the light emitting layer 114 of the columnar section 110 is equal.

In the illustrated example, the second electrode 124 and the semiconductor layer 120 are divided for each of the plurality of portions 14a, 14b, 14c, 14d, 14e, 14f. Since the second electrode 124 and the semiconductor layer 120 are divided, the injection current amount per unit area can be changed for each of the plurality of portions 14a, 14b, 14c, 14d, 14e, 14f. Thereby, the amount of light emission per unit area can be made different for each of the plurality of portions 14a, 14b, 14c, 14d, 14e, 14f. Each of the divided second electrodes 124 is connected to a wiring (not shown). The portion between the adjacent portions has such a size that the intensity of the emitted light continuously changes from one portion toward the other portion. The size of the portion between the adjacent portions is sufficiently smaller than the size of the portions 14a, 14b, 14c, 14d, 14e, 14f. In the illustrated example, the planar shape of the plurality of portions 14a, 14b, 14c, 14d, 14e, 14f is that of the second electrode 124 divided corresponding to each of the portions 14a, 14b, 14c, 14d, 14e, 14f. The plane shape and the plane shape of the semiconductor layer 120 are the same.

The plurality of portions 14a, 14b, 14c, 14d, 14e, and 14f have a larger amount of light emission per unit area as they are farther from the center C of the light emitting unit 12 when viewed in the stacking direction. The "center C of the light emitting portion 12" is the center of the smallest circle that includes the light emitting portion 12 inside, that is, the center of the smallest included circle, as viewed from the stacking direction.

The portions 14a, 14b, 14c, 14d, 14e, and 14f are the light emitting portion in the order of the first portion 14a, the second portion 14b, the third portion 14c, the fourth portion 14d, the fifth portion 14e, and the sixth portion 14f. 12 is away from the center C. The number of parts is not particularly limited.

The first portion 14 a of the plurality of portions is arranged including the center C of the light emitting unit 12. In the illustrated example, the first portion 14a has a circular shape, and the center of the first portion 14a coincides with the center C of the light emitting unit 12.

The second portion 14b of the plurality of portions is adjacent to the first portion 14a. Second part 1
4b is arranged so as to surround the first portion 14a when viewed from the stacking direction. In the illustrated example, the second portion 14b has an annular shape when viewed from the stacking direction, and the center of the second portion 14b coincides with the center C of the light emitting unit 12. The light emission amount per unit area of the second portion 14b is larger than the light emission amount per unit area of the first portion 14a.

The third portion 14c of the plurality of portions is adjacent to the second portion 14b. The third portion 14c is arranged so as to surround the second portion 14b when viewed from the stacking direction. In the illustrated example, the third portion 14c has an annular shape when viewed from the stacking direction, and the center of the third portion 14c coincides with the center C of the light emitting unit 12. The light emission amount per unit area of the third portion 14c is larger than the light emission amount per unit area of the second portion 14b.

As shown in FIG. 3, when viewed from the stacking direction, the maximum distance between the outer edge 16a of the first portion 14a and the center C is A1, and the minimum distance between the outer edge 16a of the first portion 14a and the center C is B1. Then, A1 and B1 satisfy the relationship of the following expression (1).

Further, assuming that the maximum distance between the outer edge 16b of the second portion 14b and the center C is A2 and the minimum distance between the outer edge 16b of the second portion 14b and the center C is B2, A2 and B2 are expressed by the following equations. The relationship of (2) is satisfied. The outer edge 16b is an outer edge of the second portion 14b, that is, an edge on the third portion 14c side.

Further, assuming that the maximum distance between the inner edge 18b of the second portion 14b and the center C is A3 and the minimum distance between the inner edge 18b of the second portion 14b and the center C is B3, A3 and B3 are expressed by the following equations. The relationship of (3) is satisfied. The inner edge 18b is an inner edge of the second portion 14b, that is, an edge on the first portion 14a side. Note that, for convenience, in FIG. 2, the inner edges of the portions 14a, 14b, 14c, 14d, 14e, and 14f are omitted.

Further, assuming that the maximum distance between the outer edge 16c of the third portion 14c and the center C is A4 and the minimum distance between the outer edge 16c of the third portion 14c and the center C is B4, A4 and B4 are expressed by the following equations. The relationship of (4) is satisfied. The outer edge 16c is an outer edge of the third portion 14c, that is, an edge on the fourth portion 14d side.

Further, assuming that the maximum distance between the inner edge 18c of the third portion 14c and the center C is A5 and the minimum distance between the inner edge 18c of the third portion 14c and the center C is B5, A5 and B5 are given by The relationship of (5) is satisfied. The inner edge 18c is an inner edge of the third portion 14c, that is, an edge on the second portion 14b side.

In the illustrated example, the first portion 14a has a circular shape when viewed from the stacking direction. The second portion 14b has a shape (annular shape) obtained by subtracting from the circle a circle having the same center as the circle and having a smaller area than the circle. The third portion 14c has a shape (annular shape) obtained by subtracting from the circle a circle having the same center as the circle and having a smaller area than the circle. In this way, the first portion 14a, the second portion 14b, and the third portion 14c are concentrically provided. Therefore, the distance A1 and the distance B1 are the same size, the distance A2 and the distance B2 are the same size, the distance A3 and the distance B3 are the same size, and the distance A4 and the distance B4 are the same. Are the same size, and the distance A5 and the distance B5 are the same size.

When viewed from the stacking direction, the distance between the first position P1 of the outer edge 16a of the first portion 14a and the center C of the light emitting unit 12 is the distance A1. The distance between the second position P2 of the outer edge 16b of the second portion 14b and the center C of the light emitting unit 12 is the distance A2. The distance between the third position P3 of the inner edge 18b of the second portion 14b and the center C of the light emitting unit 12 is the distance A3.

The distance between the fourth position P4 of the outer edge 16a of the first portion 14a and the center C of the light emitting unit 12 is the distance B1. The distance between the fifth position P5 of the outer edge 16b of the second portion 14b and the center C of the light emitting unit 12 is the distance B2. The distance between the sixth position P6 of the inner edge 18b of the second portion 14b and the center C of the light emitting unit 12 is the distance B3.

The distance between the seventh position P7 of the outer edge 16c of the third portion 14c and the center C of the light emitting unit 12 is the distance A4. The distance between the eighth position P8 of the inner edge 18c of the third portion 14c and the center C of the light emitting unit 12 is the distance A5. The distance between the ninth position P9 of the outer edge 16c of the third portion 14c and the center C of the light emitting unit 12 is the distance B4. The distance between the tenth position P10 of the inner edge 18c of the third portion 14c and the center C of the light emitting unit 12 is the distance B5.

When viewed from the stacking direction, the center C, the first position P1, the second position P2, the third position P3, the seventh position P7, and the eighth position P8 are on a straight line. In the illustrated example, the center C and the positions P1, P2, P3, P7, and P8 are on the first virtual straight line V1. The distance between the second position P2 and the third position P3 and the distance between the seventh position P7 and the eighth position P8 are, for example, the distance A1.

The center C, the fourth position P4, the fifth position P5, the sixth position P6, the ninth position P9, and the tenth position P10 are on a straight line. In the illustrated example, the center C and the positions P4, P5, P6, P9, and P10 are on the second virtual straight line V2. The distance between the fifth position P5 and the sixth position P6 and the distance between the ninth position P9 and the tenth position P10 are, for example, the distance B1.

In the illustrated example, the first virtual straight line V1 and the second virtual straight line V2 are orthogonal to each other, but since the portions 14a, 14b, 14c are concentrically provided, the virtual straight lines V1, V2 are It can be pulled in any direction.

The fourth portion 14d of the plurality of portions is adjacent to the third portion 14c. The light emission amount per unit area of the fourth portion 14d is larger than the light emission amount per unit area of the third portion 14c.

The fifth portion 14e of the plurality of portions is adjacent to the fourth portion 14d. The light emission amount per unit area of the fifth portion 14e is larger than the light emission amount per unit area of the fourth portion 14d.

The sixth portion 14f of the plurality of portions is adjacent to the fifth portion 14e. 6th part 1
The light emission amount per unit area of 4f is larger than the light emission amount per unit area of the fifth portion 14e.

Next, a method of manufacturing the surface emitting light source 10R will be described.

As shown in FIG. 4, the reflective layer 104 and the buffer layer 106 are epitaxially grown on the substrate 102 in this order. Examples of the epitaxial growth method include MOCVD (Metal Organic Chemical Vapor Deposition) method and MBE (Molecular Beam Epitaxy) method.

Next, a mask layer 128 is formed on the buffer layer 106 by MOCVD, MBE, or the like. Next, using the mask layer 128 as a mask, the semiconductor layer 112, the light emitting layer 114, and the semiconductor layer 116 are epitaxially grown in this order on the buffer layer 106. Examples of the epitaxial growth method include MOCVD method and MBE method. Through this step, the columnar section 110 can be formed. Next, the light propagation layer 118 is formed between the adjacent columnar portions 110 by a spin coating method or the like. Through this step, the photonic crystal structure 108 can be formed.

Next, the semiconductor layer 120 is formed on the columnar section 110 and the light propagation layer 118 by, for example, the MOCVD method or the MBE method.

Next, the first electrode 122 and the second electrode 124 are formed by, for example, a vacuum vapor deposition method.

Through the above steps, the surface emitting light source 10R can be formed.

Although the InGaN-based light emitting layer 114 has been described above, the light emitting layer 114 can be made of any material system capable of emitting light when a current is injected depending on the wavelength of emitted light. .. For example, semiconductor materials such as AlGaN-based, AlGaAs-based, InGaAs-based, InGaAsP-based, InP-based, GaP-based, and AlGaP-based can be used. In addition, the size of the columnar portions 110 and the pitch of the arrangement may be changed according to the wavelength of the emitted light. By thus changing the wavelength of the emitted light, the surface emitting light source 10G emitting green light and the surface emitting light source 10B emitting blue light can be formed. The surface emitting light sources 10G and 10B have basically the same configuration as the surface emitting light source 10R except that the wavelengths of the emitted light are different.

Further, in the above, the photonic crystal structure 108 has the columnar portions 110 that are periodically provided, but in order to exert the photonic crystal effect, the photonic crystal structure 108 has the periodically provided holes. May be. In this case, the plurality of portions are classified by the amount of current injected into the light emitting layer 114 included in the plurality of portions.

The projector 100 has the following features, for example.

In the projector 100, the distance A1 and the distance B1 satisfy the equation (1), the distance A2 and the distance B2 satisfy the equation (2), the distance A3 and the distance B3 satisfy the equation (3), and the center C and the position P1, P2, P3 are on a straight line, and the center C and the positions P4, P5, P6 are on a straight line. Therefore, in the projector 100, the ratio A1/B1 can be made smaller than in the case where the first portion is rectangular. Further, the ratio A2/B2 and the ratio A3/A3 can be made smaller than in the case where the second portion has a shape obtained by subtracting a rectangle having the same center as the rectangle and a smaller area than the rectangle from the rectangle. .. Therefore, in the projector 100, it is possible to reduce the unevenness in brightness that occurs in the projection image projected on the screen or the like by the projection lens 60. Therefore, it is possible to obtain a projected image with high uniformity of light intensity.

Here, when the shape of the first portion is rectangular, the ratio A1/B1 is the smallest when the shape of the first portion is square, and the value thereof is √2. Therefore, by satisfying the expression (1), the ratio A1/B1 can be made smaller than in the case where the shape of the first portion is rectangular.

Further, in the projector 100, even in the magnifying illumination system including the concave lens 20 and the convex lens 22, the light utilization efficiency is reduced in the peripheral portion away from the optical axis of the magnifying illumination system, similarly to the projection lens 60. However, in the projector 100, by satisfying the equations (1), (2), and (3), unevenness in brightness caused in the projection image projected on the screen or the like due to the light utilization efficiency of the magnifying illumination system, It can be reduced.

In a magnifying illumination system that expands the luminous flux diameter, the luminous flux density decreases at the peripheral portion away from the optical axis due to the aberration generated in the optical system. Therefore, even if light having a uniform intensity enters the magnifying illumination system, the luminous flux emitted from the magnifying illumination system has a large intensity near the optical axis, and has a non-uniformity that the intensity decreases as the distance from the optical axis increases. This phenomenon becomes more remarkable as the enlargement ratio increases.

In the projector 100, the distance A4 and the distance B4 satisfy the equation (4), the distance A5 and the distance B5 satisfy the equation (5), and the center C and the positions P1, P7, and P8 are on a straight line, and the center C And the positions P4, P9, and P10 are on a straight line. Therefore, in the projector 100, the ratio A4/B4 and the ratio A5/B5 are made smaller than in the case where the third portion has a shape obtained by subtracting a rectangle having the same center as the rectangle and a smaller area than the rectangle from the rectangle. be able to.

In the projector 100, the surface-emitting light sources 10R, 10G, and 10B each include a substrate 102 and a stacked body 103 that is provided on the substrate 102 and includes a light emitting layer 114 that emits light. A photonic crystal structure 108 is formed in which the emitted light is confined in the in-plane direction of the substrate 102 and emitted in the normal direction of the substrate 102. Therefore, the surface emitting light sources 10R, 10G, and 10B can emit light with a small emission angle and high intensity uniformity.

1.2. Modification 1.2.1. First Modified Example Next, a projector 130 according to a first modified example of the first embodiment will be described with reference to the drawings. FIG. 5 is a plan view schematically showing the surface emitting light source 10R of the projector 130 according to the first modified example of the first embodiment. FIG. 6 is an enlarged view of FIG. Note that, for convenience, in FIG. 5, the inner edges of the portions 14a, 14b, 14c, 14d, 14e, and 14f are omitted. Further, in FIG. 6, members other than the light emitting unit 12 are not shown.

Hereinafter, in the projector 130 according to the first modified example of the first embodiment, different points from the example of the projector 100 according to the first embodiment described above will be described, and description of the same points will be omitted. This is the same in the second to fourth modified examples according to the first embodiment described later.

In the projector 100 described above, as shown in FIGS. 2 and 3, the first portion 14a, the second portion 14b, and the third portion 14c are concentrically provided when viewed in the stacking direction.

On the other hand, in the projector 130, as shown in FIGS. 5 and 6, the first portion 14a has a regular hexagonal shape when viewed from the stacking direction. The second portion 14b has a shape obtained by subtracting from the regular hexagon a regular hexagon having the same center as the regular hexagon and a smaller area than the regular hexagon. The third portion 14c has a shape obtained by subtracting from the regular hexagon a regular hexagon having the same center as the regular hexagon and a smaller area than the regular hexagon. In this way, the first portion 14a, the second portion 14b, and the third portion 14c are provided in a concentric regular hexagonal shape.

The first portion 14a, the second portion 14b, and the third portion 14c are not limited to the concentric circular shape or the concentric regular hexagonal shape, and the shape is not limited to the circular shape or the regular hexagonal shape, and the expressions (1), ( It is optional as long as the conditions 2) and 3) are satisfied. Further, the shapes of the portions 14a, 14b, 14c, 14d, 14e, and 14f do not have to correspond to the shape of the second electrode 124 when viewed from the stacking direction. For example, the second electrode 124 is divided into a plurality of matrix shapes in the first direction and a second direction orthogonal to the first direction, and a current is injected into the columnar section 110 by the plurality of divided second electrodes 124. The shapes of the portions 14a, 14b, 14c, 14d, 14e, 14f may be defined.

1.2.2. Second Modified Example Next, a projector 140 according to a second modified example of the first embodiment will be described with reference to the drawings. FIG. 7 is a plan view schematically showing the surface emitting light source 10R of the projector 140 according to the second modified example of the first embodiment. FIG. 8 is an enlarged view of FIG. 7. FIG. 9 is a side view schematically showing the incident end surface of the projection lens 60 of the projector 140 according to the second modified example of the first embodiment. For convenience, in FIG. 7, the inner edges of the portions 14a, 14b, 14c, 14d, 14e, 14f, and 14g are omitted. Further, in FIG. 8, members other than the light emitting unit 12 are not shown.

In the projector 100 described above, as shown in FIG. 2, the distance between the second position P2 and the third position P3 is the distance A1.

On the other hand, in the projector 140, as shown in FIGS. 7 and 8, the distance W1 between the second position P2 and the third position P3 is smaller than the distance A1.

In the projector 140, the light emitting unit 12 has the seventh portion 14g. The seventh portion 14g of the plurality of portions is adjacent to the sixth portion 14f. The light emission amount per unit area of the seventh portion 14g is larger than the light emission amount per unit area of the sixth portion 14f.

As shown in FIG. 8, the distance W2 is the distance between the outer edge 16c and the inner edge 18c of the third portion 14c on the first virtual straight line V1. The distance W3 is a distance between the outer edge 16d and the inner edge 18d of the fourth portion 14d on the first virtual straight line V1. The distance W4 is a distance between the outer edge 16e and the inner edge 18e of the fifth portion 14e on the first virtual straight line V1. The distance W2 is smaller than the distance W1. The distance W3 is smaller than the distance W2. The distance W4 is smaller than the distance W3.

Furthermore, in the projector 140, the distance W5 between the fifth position P5 and the sixth position P6 is smaller than the distance B1.

In general, the incident end surface 62 of the projection lens 60 on which light first enters has a convex shape in which the curvature increases as the distance from the optical axis L increases, as shown in FIG. The optical axis L is the optical axis of the projection lens 60. Therefore, in the peripheral portion far from the optical axis L, the aberration that occurs is likely to increase, and even when light with a uniform luminous flux intensity is incident, the luminous flux intensity decreases toward the peripheral portion and uneven brightness occurs.

In the projector 140, the distance W1 between the second position P2 and the third position P3 is smaller than the distance A1, and the distance W5 between the fifth position P5 and the sixth position P6 is smaller than the distance B1. Therefore, when the incident end surface 62 of the projection lens 60 has a convex shape in which the curvature increases as the distance from the optical axis L increases, unevenness in brightness caused by the difference in the curvature can be reduced.

1.2.3. Third Modified Example Next, a projector 150 according to a third modified example of the first embodiment will be described with reference to the drawings. FIG. 10 is a cross-sectional view schematically showing the surface emitting light source 10R of the projector 150 according to the third modified example of the first embodiment.

In the surface emitting light source 10R of the projector 100 described above, as shown in FIG. 4, the columnar portion 110 of the photonic crystal structure 108 has the light emitting layer 114.

On the other hand, in the surface emitting light source 10R of the projector 150, as shown in FIG. 10, the columnar section 110 does not have the light emitting layer 114.

In the projector 150, the material of the columnar section 110 is, for example, n-type GaN doped with Si. The photonic crystal structure 108 includes a columnar section 110 and a gap 111 between adjacent columnar sections 110. In the illustrated example, a tapered portion 113 having a diameter gradually increasing upward is provided on the columnar portion 110. The material of the tapered portion 113 is the same as that of the columnar portion 110. The taper portion 113 may not be provided.

The semiconductor layer 112 is provided on the tapered portion 113. The light emitting layer 114 is provided on the semiconductor layer 112. The semiconductor layer 116 is provided on the light emitting layer 114. The first electrode 122 is provided on the semiconductor layer 112. The second electrode 124 is provided on the semiconductor layer 116. In the projector 150, the light emitting unit 12 is a portion of the light emitting layer 114 when viewed from the stacking direction. When the surface-emitting light source 10R is a photonic crystal laser including the columnar section 110 having no light emitting layer 114, the light emitting section 12 is the light emitting layer 114. The plurality of portions 14a, 14b, 14c, 14d, 14e, 14f are classified according to the amount of current injected into the light emitting layer 114.

Although not shown, the semiconductor layers 112 and 116 and the light emitting layer 114 may be provided between the substrate 102 and the photonic crystal structure 108.

When the photonic crystal structure 108 does not have the light emitting layer 114 like the projector 150, the light leaked from the light emitting layer 114 to the photonic crystal structure 108 side is confined in the direction orthogonal to the stacking direction. And ejected in the stacking direction.

1.2.4. Fourth Modification Example Next, a projector 160 according to a fourth modification example of the first embodiment will be described with reference to the drawings. FIG. 11 is a diagram schematically showing the projector 160 according to the fourth modified example of the first embodiment. Note that, for convenience, in FIG. 11, members other than the surface emitting light source 10R, the convex lenses 22 and 24, the polarization elements 30 and 32, and the light modulation element 40 are omitted.

In the projector 100 described above, as shown in FIG. 1, the projector 100 has a Galilean-type magnifying illumination system including a concave lens 20 and a convex lens 22.

On the other hand, the projector 160 has a Kepler-type magnifying illumination system including convex lenses 22 and 24, as shown in FIG. In the Kepler-type magnifying illumination system, it is easy to obtain a large magnifying power in magnifying the light flux diameter.

Note that, as shown in FIG. 12, a relay lens 26 may be arranged between the convex lenses 22 and 24. The light emitting section 12 of the surface emitting light source 10R and the illuminated surface of the light modulation element 40 have an optically conjugate relationship, and even if the light emitted from the surface emitting light source 10R has a slightly large emission angle, The light modulation element 40 can be illuminated with high efficiency.

2. Second Embodiment Next, a projector 200 according to the second embodiment will be described with reference to the drawings. FIG. 13 is a diagram schematically showing the projector 200 according to the second embodiment.

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

In the projector 100 described above, as shown in FIG. 1, the light modulation element 40 is a transmissive liquid crystal light valve that transmits the light emitted from the surface emitting light sources 10R, 10G, and 10B.

On the other hand, in the projector 200, as shown in FIG. 13, the light modulation element 40 is a reflective liquid crystal light valve that reflects light emitted from the surface emitting light sources 10R, 10G, and 10B. The projector 200 is an LCoS (Liquid Crystal on Silicon) projector.

The projector 200 has a polarization separation element 80. The light emitted from the surface emitting light sources 10R, 10G, and 10B passes through the concave lens 20 and the convex lens 22 to increase the diameter of the light flux, and then enters the polarization separation element 80. In the illustrated example, the polarization separation element 80 is fixed to the color light combining prism 50 via a spacer 82. Three polarization separation elements 80 are provided corresponding to the surface emitting light sources 10R, 10G and 10B.

The polarization separation element 80 is, for example, a polarization beam splitter. The polarization beam splitter is an optical element configured to sandwich the polarization separation film 84 between the inclined surfaces of a pair of right-angle prisms made of glass. The polarization separation element 80 transmits a specific linearly polarized light, for example, P-polarized light to the polarization separation film 84, and linearly polarized light whose polarization direction is orthogonal to the linearly polarized light, for example, S-polarized light to the polarization separation film 84. To reflect. Utilizing this function, the polarization separation element 80 spatially separates the illumination light incident on the light modulation element 40 and the image light emitted from the light modulation element 40.

For example, linearly polarized light having a high degree of polarization is emitted from the surface emitting light sources 10R, 10G, and 10B, and the polarization direction of the linearly polarized light is set to be P-polarized with respect to the polarization separation film 84. The P-polarized light emitted from the surface emitting light sources 10R, 10G, and 10B passes through the polarization separation film 84 of the polarization separation element 80 and enters the light modulation element 40. The polarized light other than the P-polarized light that may slightly exist is reflected by the polarization separation film 84, so that only the P-polarized light enters the light modulation element 40. The light that has entered the light modulation element 40 is subjected to a light modulation action and converted into S-polarized light to form image light, which is reflected in the direction opposite to that at the time of incidence and exits from the light modulation element 40. The S-polarized image light emitted from the light modulation element 40 is reflected by the polarization separation film 84, bent in the traveling direction by 90°, and emitted from the polarization separation element 80. The image light emitted from the polarization separation element 80 is reflected by the spacer 8
After passing through 2, the light enters the color light combining prism 50. The image light emitted from the color light combining prism 50 enters the projection lens 60.

3. Third Embodiment Next, a projector 300 according to the third embodiment will be described with reference to the drawings. FIG. 14 is a diagram schematically showing the projector 300 according to the third embodiment.

Hereinafter, in the projector 300 according to the third embodiment, different points from the example of the projector 100 according to the above-described first embodiment will be described, and description of the same points will be omitted.

In the projector 100 described above, as shown in FIG. 1, the light modulation element 40 is a transmissive liquid crystal light valve that transmits the light emitted from the surface emitting light sources 10R, 10G, and 10B.

On the other hand, in the projector 300, as shown in FIG. 14, the light modulation element 40 is a DMD (Digital Micromirror Device, registered trademark) that reflects the light emitted from the surface emitting light sources 10R, 10G, and 10B. The DMD is a light modulation element that includes a large number of micromirrors and changes the direction of each micromirror to control the emission direction of reflected light. The projector 300 is a DLP (Digital Light Processing, registered trademark) projector.

The projector 300 has a total reflection prism 90. The light emitted from the surface emitting light sources 10R, 10G, and 10B enters the color light combining prism 50, then passes through the concave lens 20 and the convex lens 22 to expand the light beam diameter, and then enters the total reflection prism 90.

The total reflection prism 90 has a first prism 92 and a second prism 94 made of glass, and the first prism 92 and the second prism 94 are integrally fixed via a spacer 96. An air gap G is provided between the first prism 92 and the second prism 94. The light emitted from the color light combining prism 50 enters the first prism 92, is then totally reflected by the air gap G, and enters the light modulation element 40. The light modulated by the light modulation element 40 passes through the total reflection prism 90 and enters the projection lens 60.

The present invention may omit some of the configurations or combine the embodiments and modifications within the scope of the features and effects described in the present application.

The present invention is not limited to the above-described embodiment, and various modifications can be made. For example, the invention includes configurations that are substantially the same as the configurations described in the embodiments. The substantially same structure is, for example, a structure having the same function, method, and result, or a structure having the same object and effect. Further, the invention includes configurations in which non-essential parts of the configurations described in the embodiments are replaced. Further, the invention includes a configuration that achieves the same effects as the configurations described in the embodiments or a configuration that can achieve the same object. Further, the invention includes configurations in which known techniques are added to the configurations described in the embodiments.

10R, 10G, 10B... Surface emitting light source, 12... Light emitting part, 14a... 1st part, 14b... 2nd part, 14c... 3rd part, 14d... 4th part, 14e... 5th part, 14f... 6th part , 14g... Seventh part, 16a, 16b, 16c, 16d, 16e... Outer edge, 18b, 18c, 18d, 18e... Inner edge, 20... Concave lens, 22... Convex lens, 24... Convex lens, 26... Relay lens, 30... First Polarizing element, 32... Second polarizing element, 40... Light modulating element, 50... Color light combining prism, 60... Projection lens, 62... Incident end face, 70... Radiating fin, 80... Polarization separating element, 82... Spacer, 84... Polarized light Separation film, 90... Total reflection prism, 92... First prism, 94... Second prism, 96... Spacer, 100... Projector, 102... Substrate, 103... Laminated body, 104... Reflection layer, 106... Buffer layer, 108... Photonic crystal structure, 110... Columnar section, 111... Gap, 112... Semiconductor layer, 113... Tapered section, 114... Light emitting layer, 116... Semiconductor layer, 118... Light propagation layer, 120... Semiconductor layer, 122... First Electrode, 124... Second electrode, 128... Mask layer, 130, 140, 150, 160, 200, 300... Projector

Claims (5)

A surface emitting light source having a light emitting portion,
Light emitted from the surface emitting light source, a light modulation element for modulating according to image information,
An image formed by the light modulation element is projected, and a projection lens that is circular when viewed from the optical axis direction,
Including
The light emitting unit has a plurality of portions having different amounts of light emission per unit area,
The plurality of portions have a larger amount of light emission per unit area as the portions are farther from the center of the light emitting portion when viewed in the light emission direction.
A first portion of the plurality of portions is disposed including the center,
A second portion of the plurality of portions is arranged adjacent to the first portion and surrounding the first portion when viewed from the emission direction,
Assuming that the maximum distance between the outer edge of the first portion and the center is A1 and the minimum distance between the outer edge of the first portion and the center is B1 as viewed from the emission direction, the A1 and the B1 are Satisfies the relationship of the following formula (1),
Assuming that the maximum distance between the outer edge of the second portion and the center is A2 and the minimum distance between the outer edge of the second portion and the center is B2, the A2 and the B2 are expressed by the following formula (2). ) Relationship,
Assuming that the maximum distance between the inner edge of the second portion and the center is A3 and the minimum distance between the inner edge of the second portion and the center is B3, A3 and B3 are expressed by the following formula (3). ) Relationship,
The distance between the first position of the outer edge of the first portion and the center is A1;
The distance between the second position of the outer edge of the second portion and the center is A2,
The distance between the third position of the inner edge of the second portion and the center is A3,
The distance between the fourth position of the outer edge of the first portion and the center is B1,
The distance between the fifth position of the outer edge of the second portion and the center is B2,
The distance between the sixth position of the inner edge of the second portion and the center is B3,
The center, the first position, the second position, and the third position are on a straight line,
The projector in which the center, the fourth position, the fifth position, and the sixth position are on a straight line.

In claim 1,
A third portion of the plurality of portions is arranged adjacent to the second portion and surrounding the second portion when viewed from the emission direction,
Assuming that the maximum distance between the outer edge of the third portion and the center is A4 and the minimum distance between the outer edge of the third portion and the center is B4 as viewed from the injection direction, the A4 and the B4 are the same. Satisfies the relationship of the following formula (4),
Assuming that the maximum distance between the inner edge of the third portion and the center is A5 and the minimum distance between the inner edge of the third portion and the center is B5, the A5 and the B5 are expressed by the following formula (5). ) Relationship,
The distance between the seventh position of the outer edge of the third portion and the center is A4,
The distance between the eighth position of the inner edge of the third portion and the center is A5,
The distance between the ninth position of the outer edge of the third portion and the center is B4,
The distance between the tenth position of the inner edge of the third portion and the center is B5,
The center, the first position, the seventh position, and the eighth position are on a straight line,
The projector in which the center, the fourth position, the ninth position, and the tenth position are on a straight line.

In claim 1 or 2,
The incident end surface of the projection lens has a convex shape in which the curvature increases as the distance from the optical axis increases,
The distance between the second position and the third position is smaller than the A1,
The projector in which the distance between the fifth position and the sixth position is smaller than B1. In any one of Claim 1 thru|or 3,
The surface emitting light source is
Board,
A laminate having a light emitting layer which is provided on the substrate and emits light;
Have
The projector, wherein the stacked body constitutes a photonic crystal structure for confining light emitted from the light emitting layer in an in-plane direction of the substrate and emitting the light in a normal direction of the substrate. In any one of Claim 1 thru|or 4,
The projector in which the light emitting unit has a rectangular shape when viewed from the emission direction.

Images