Abstract: A wavelength conversion element includes a base material and a phosphor layer that contains a phosphor emitting fluorescence upon incidence of excitation light and is provided on the base material, in which the phosphor layer includes a first surface on which excitation light (blue light) is incident and a second surface facing the base material, and a plurality of regions with different absorption coefficients of the excitation light between the first surface and the second surface.

Abstract: A light source device includes a first light source configured to emit excitation light having a first wavelength band, a wavelength conversion member having a plurality of surfaces and configured to convert the excitation light made incident from the first light source into converted light having a second wavelength band different from the first wavelength band, and a first light transmissive member provided between the first light source and the wavelength conversion member and configured to transmit the excitation light. The wavelength conversion member includes a first surface on which the excitation light from the first light source is made incident. The first light transmissive member includes, on a surface opposed to the first surface of the wavelength conversion member, a first reflection layer that transmits the excitation light and reflects the converted light. A gap is provided between the first surface and the first reflection layer.

Abstract: A light source device includes a first light source configured to emit excitation light in a first wavelength band and a wavelength conversion member having a plurality of surfaces and configured to convert the excitation light made incident from the first light source into converted light in a second wavelength band different from the first wavelength band. The wavelength conversion member includes a first surface on which the excitation light is made incident, a second surface opposed to the first surface, and a third surface that emits the converted light. A first reflection layer that transmits the excitation light and reflects the converted light is provided on the first surface.

Abstract: A light source apparatus includes a light source that outputs excitation light, and a rotating light emitting device in which a wavelength conversion element that emits light when irradiated with the excitation light is provided on a rotating disk. A spot of the excitation light on the wavelength conversion element has a shape that is long in a radial direction of the rotating disk and short in a circumferential direction of the rotating disk. Alternatively, an orthogonally projected length of the spot in the radial direction is greater than an orthogonally projected length of the spot in the circumferential direction.

Abstract: A light source device according to the invention includes a light source, a light separating/combining element including a dichroic layer, a wavelength conversion layer, and a diffusely reflecting element. A bundle of light beams emitted from the light source includes a first light bundle and a second light bundle. The first light bundle enters the wavelength conversion layer via the dichroic layer. The second light bundle enters the diffusely reflecting element without entering the dichroic layer, and is converted into diffusely reflected light. The dichroic layer combines the third light bundle from the wavelength conversion layer and the diffusely reflected light from the diffusely reflecting element with each other.

Abstract: A wavelength conversion element includes a base material and a phosphor layer that contains a phosphor emitting fluorescence upon incidence of excitation light and is provided on the base material, in which the phosphor layer includes a first surface on which excitation light (blue light) is incident and a second surface facing the base material, and a plurality of regions with different absorption coefficients of the excitation light between the first surface and the second surface.

Abstract: A wavelength conversion element according to the invention includes: a base material; a wavelength conversion layer supported by one surface of the base material and containing a wavelength conversion material and an inorganic binder; a light transmitting layer provided in a side of the wavelength conversion layer opposite to the base material and made of an inorganic material; and an antireflection film provided in a side of the light transmitting layer opposite to the wavelength conversion layer.

Abstract: A light source device according to the invention includes a light source, a light separating/combining element including a dichroic layer, a wavelength conversion layer, and a diffusely reflecting element. A bundle of light beams emitted from the light source includes a first light bundle and a second light bundle. The first light bundle enters the wavelength conversion layer via the dichroic layer. The second light bundle enters the diffusely reflecting element without entering the dichroic layer, and is converted into diffusely reflected light. The dichroic layer combines the third light bundle from the wavelength conversion layer and the diffusely reflected light from the diffusely reflecting element with each other.

Abstract: A fluorescence light emitting element includes a phosphor layer that includes phosphors and a binder made of an inorganic material. A thermal conductivity B of the binder is larger than 1.88 times a thermal conductivity A of the phosphors. When the volume of the phosphors included in the phosphor layer is X and the volume of the binder included in the phosphor layer is Y, a relationship of X/Y>1/2 is satisfied.

Abstract: A light source apparatus includes a light emitting device that has a first light emitting region outputting first excitation light and a second light emitting region outputting second excitation light, a phosphor layer that is so provided that the phosphor layer coincides with the first light emitting region in a plan view and emits fluorescence light, a reflector that is provided on the opposite side of the phosphor layer to the light emitting device, transmits the fluorescence light, and reflects the excitation light, and a light guide section that is disposed on an optical path between the phosphor layer and the reflector, and guides the second excitation light reflected off the reflector such that at least part of the reflected second excitation light enters the phosphor layer.

Abstract: A light source apparatus includes a light source that outputs excitation light, and a rotating light emitting device in which a wavelength conversion element that emits light when irradiated with the excitation light is provided on a rotating disk. A spot of the excitation light on the wavelength conversion element has a shape that is long in a radial direction of the rotating disk and short in a circumferential direction of the rotating disk. Alternatively, an orthogonally projected length of the spot in the radial direction is greater than an orthogonally projected length of the spot in the circumferential direction.

Abstract: A fluorescence light emitting element includes a phosphor layer that includes phosphors and a binder made of an inorganic material. A thermal conductivity B of the binder is larger than 1.88 times a thermal conductivity A of the phosphors. When the volume of the phosphors included in the phosphor layer is X and the volume of the binder included in the phosphor layer is Y, a relationship of X/Y>1/2 is satisfied.

Abstract: A light source apparatus includes a light emitting device that has a first light emitting region outputting first excitation light and a second light emitting region outputting second excitation light, a phosphor layer that is so provided that the phosphor layer coincides with the first light emitting region in a plan view and emits fluorescence light, a reflector that is provided on the opposite side of the phosphor layer to the light emitting device, transmits the fluorescence light, and reflects the excitation light, and a light guide section that is disposed on an optical path between the phosphor layer and the reflector, and guides the second excitation light reflected off the reflector such that at least part of the reflected second excitation light enters the phosphor layer.

Abstract: A screen in which observation distance may be adjusted while maintaining image brightness and a projection system using the screen. In a light control layer of a screen, a first angle region that determines a diffusion distribution of a reflected light is different according to the screen position in a control direction in which light diffusion control is performed. Accordingly, a diffusion distribution of image light emitted from a screen surface is adjusted to be tilted downward by an upper end and upward by a lower end according to the screen position. Thus, for example, a size of a diffused angle range is maintained to be 30°, and a direction in which the image light is diffusion-emitted corresponds to an assumed position of an observer. The projection image can be observed while maintaining brightness of an image and the observation distance L can be adjusted to be short.

Abstract: A projector includes a light source, a first light separation optical system adapted to separate light emitted from the light source into first light and second light, a second light separation optical system adapted to separate the first light into third light and fourth light, separate the second light into fifth light and sixth light, and emit the third light, the fourth light, the fifth light, and the six light in directions intersecting with a plane including a light axis of the light emitted from the light source and a light axis of the first light, and a light modulation element which the third light, the fourth light, the fifth light, and the sixth light enter.

Abstract: A screen which reflects light emitted from a projector includes a light diffusion layer through which light incident from a specific angular region is diffused and transmitted and through which light incident from the other angular region is transmitted straight; area pairs having a mirror forming area and a non-mirror forming area; a light transmissive layer having a back surface, on which the area pairs are disposed, and an opposite surface being bonded to a back side of the light diffusion layer; and a specular reflection film formed on a back surface of each mirror forming area. An inclination of the mirror forming area with respect to a normal line of the screen close to the projector becomes larger than the inclination of the mirror forming area far from the projector within a cross section perpendicular to the mirror forming areas inside the screen.

Abstract: A screen in which observation distance may be adjusted while maintaining image brightness and a projection system using the screen. In a light control layer of a screen, a first angle region that determines a diffusion distribution of a reflected light is different according to the screen position in a control direction in which light diffusion control is performed. Accordingly, a diffusion distribution of image light emitted from a screen surface is adjusted to be tilted downward by an upper end and upward by a lower end according to the screen position. Thus, for example, a size of a diffused angle range is maintained to be 30°, and a direction in which the image light is diffusion-emitted corresponds to an assumed position of an observer. The projection image can be observed while maintaining brightness of an image and the observation distance can be adjusted to be short.

Abstract: A projector includes a light source, a first light separation optical system adapted to separate light emitted from the light source into first light and second light, a second light separation optical system adapted to separate the first light into third light and fourth light, separate the second light into fifth light and sixth light, and emit the third light, the fourth light, the fifth light, and the six light in directions intersecting with a plane including a light axis of the light emitted from the light source and a light axis of the first light, and a light modulation element which the third light, the fourth light, the fifth light, and the sixth light enter.

Abstract: A screen which reflects light emitted from a projector includes a light diffusion layer through which light incident from a specific angular region is diffused and transmitted and through which light incident from the other angular region is transmitted straight; area pairs having a mirror forming area and a non-mirror forming area; a light transmissive layer having a back surface, on which the area pairs are disposed, and an opposite surface being bonded to a back side of the light diffusion layer; and a specular reflection film formed on a back surface of each mirror forming area. An inclination of the mirror forming area with respect to a normal line of the screen close to the projector becomes larger than the inclination of the mirror forming area far from the projector within a cross section perpendicular to the mirror forming areas inside the screen.

Abstract: A projector for separating white light into three primary colors, forming images with liquid crystal light valves, mixing these images, and projecting an enlarged picture of the mixed images with a projection lens. The projector includes an optical unit having a light source, a plurality of dichroic mirrors for separating the white light into blue, green, and red beams, respective liquid crystal light valves forming images of the blue, green, and red colors. The optical unit has a chassis with a rigid center portion at which one of the liquid crystal light valves is mounted, the other two light valves being mounted symmetrically with respect thereto. An adjustment mechanism is provided for matching pixels of the second and third color valves with those of the first color valve. The red color liquid crystal light valve is disposed midway between the blue and green color liquid crystal light valves and a cooling fan is disposed below the red color liquid crystal light valve.