Abstract: The cross dichroic prism according to the present disclosure includes four prisms and two dichroic mirrors. Each of the four prisms has a triangle-prism shape. The four prisms are arranged to form a quadrangular prism as a whole in a manner such that the ridge line portions are located close to each other, a first plane of one prism faces a second plane of another prism, and a third plane faces outward. Each of the two dichroic mirrors is constituted of a dielectric multilayer film provided between the first plane of one prism and the second plane of another prism. The outermost layer of a dielectric layer constituting the dielectric multilayer film is provided in contact with each of the first plane of the one prism and the second plane of the other prism.

Abstract: A wavelength conversion element according to the present disclosure includes a substrate, a dichroic layer provided to a first surface of the substrate, an intermediate layer disposed so as to be opposed to the substrate via the dichroic layer, and a wavelength conversion layer disposed so as to be opposed to the dichroic layer via the intermediate layer, and configured to convert light in a first wavelength band into light in a second wavelength band. The dichroic layer has two or more types of refractive index layers having respective refractive indexes different from each other.

Abstract: A virtual image display apparatus includes an image light emitting unit configured to emit image light, and a see-through mirror which is an optical member having a reflective film that reflects the image light, wherein the see-through mirror includes a first region on which a light ray of the image light corresponding to a center angle of view is incident and a second region on which a light ray of the image light which different from the light ray corresponding to the center angle of view is incident, a film thickness in the first region of the reflective film is thicker than a film thickness in the second region, and the first region of the reflective film has reflectivity characteristics corresponding to a wavelength band which is wider toward the long wavelength side than a wavelength band of the image light emitted from the image light emitting unit.

Abstract: An optical unit and an image display device include a display element configured to emit imaging light, a first mirror having partial transparency and configured to reflect a portion of the imaging light emitted from the display element, and a second mirror configured to return the imaging light reflected by the first mirror to the first mirror to form an exit pupil. The imaging light is incident on the first mirror from the display element at a first incident angle, and the imaging light is incident on the first mirror at a second incident angle that is smaller than the first incident angle from the second mirror, and the first mirror includes an angle dependent separation film that shows different separation characteristics for the imaging light according to the difference between the first incident angle and the second incident angle.

Abstract: An image light generation device of the present disclosure includes first to third display elements configured to emit first to third color light, respectively, and a color synthesis element configured to synthesize the first to third color light. The color synthesis element includes first to third prisms, a first dichroic film configured to reflect the first color light and transmit the second and third color light, and a second dichroic film configured to reflect the second color light and transmit the third color light. The first and second prisms are joined together through a first dichroic film with no air layer therebetween, the second and third prisms are joined together through a second dichroic film with no air layer therebetween, and the main light beam incidence angle of the third color light to the second dichroic film is 40 degrees or greater.

Abstract: The cross dichroic prism according to the present disclosure includes four prisms and two dichroic mirrors. Each of the four prisms has a triangle-prism shape. The four prisms are arranged to form a quadrangular prism as a whole in a manner such that the ridge line portions are located close to each other, a first plane of one prism faces a second plane of another prism, and a third plane faces outward. Each of the two dichroic mirrors is constituted of a dielectric multilayer film provided between the first plane of one prism and the second plane of another prism. The outermost layer of a dielectric layer constituting the dielectric multilayer film is provided in contact with each of the first plane of the one prism and the second plane of the other prism.

Abstract: The cross dichroic prism according to the present disclosure includes four prisms and two dichroic mirrors. Each of the four prisms has a triangle-prism shape. The four prisms are arranged to form a quadrangular prism as a whole in a manner such that the ridge line portions are located close to each other, a first plane of one prism faces a second plane of another prism, and a third plane faces outward. Each of the two dichroic mirrors is constituted of a dielectric multilayer film provided between the first plane of one prism and the second plane of another prism. The outermost layer of a dielectric layer constituting the dielectric multilayer film is provided in contact with each of the first plane of the one prism and the second plane of the other prism.

Abstract: A wavelength conversion element according to the present disclosure includes a substrate, a dichroic layer provided to a first surface of the substrate, an intermediate layer disposed so as to be opposed to the substrate via the dichroic layer, and a wavelength conversion layer disposed so as to be opposed to the dichroic layer via the intermediate layer, and configured to convert light in a first wavelength band into light in a second wavelength band. The dichroic layer has two or more types of refractive index layers having respective refractive indexes different from each other.

Abstract: Provided are an optical unit and a display device that can appropriately perform reflection and transmission of image light emitted from a panel provided with a light emitting element, over a wide wavelength region in a dichroic mirror. The optical unit includes a first panel, a second panel, and a third panel arranged facing a first incident surface, a second incident surface, and a third incident surface of a dichroic prism, respectively, and each of the first panel, the second panel, and the third panel emits unpolarized image light. A polarization element is arranged between the first panel and the dichroic prism, and first image light emitted from the first panel is incident on the dichroic prism as linearly polarized light. A first dichroic mirror has polarization separation characteristics in addition to transmittance-wavelength characteristics.

Abstract: An image light generation device of the present disclosure includes first to third display elements configured to emit first to third color light, respectively, and a color synthesis element configured to synthesize the first to third color light. The color synthesis element includes first to third prisms, a first dichroic film configured to reflect the first color light and transmit the second and third color light, and a second dichroic film configured to reflect the second color light and transmit the third color light. The first and second prisms are joined together through a first dichroic film with no air layer therebetween, the second and third prisms are joined together through a second dichroic film with no air layer therebetween, and the main light beam incidence angle of the third color light to the second dichroic film is 40 degrees or greater.

Abstract: A wavelength conversion element includes a wavelength conversion layer which has a first face on which an excitation light is incident and a second face facing the first face, a first layer which is provided facing the second face and contains a first inorganic oxide, a second layer which is provided facing the first layer and contains a first metal or a second inorganic oxide that is different from the first inorganic oxide, and a third layer which is provided facing the second layer, contains either silver or aluminum, and reflects the excitation light or a light obtained by wavelength conversion of the excitation light by the wavelength conversion layer.

Abstract: An encoder includes a light emitting portion emitting light, an optical element portion splitting the light into a first beam and a second beam, an optical scale receiving the first beam and the second beam from the optical element portion, and a light receiving portion receiving the first beam and the second beam from the optical scale and outputting a signal in accordance with intensity of the received light, in which the optical element portion includes a prism on which the light is incident, a beam splitter disposed on the prism and splitting the light incident on the prism into the first beam heading for the optical scale and the second beam heading for an inside of the prism, and a first mirror portion disposed on the prism and reflecting the second beam from the beam splitter toward the optical scale.

Abstract: An optical device combines light emitted from first and second display panels. The first display panel emits first color light from a plurality of pixels. The second display panel emits second color light having a different wavelength range from the first color light from a plurality of pixels and emits third color light having a different wavelength range from the second color light from a plurality of pixels.

Abstract: The cross dichroic prism according to the present disclosure includes four prisms and two dichroic mirrors. Each of the four prisms has a triangle-prism shape. The four prisms are arranged to form a quadrangular prism as a whole in a manner such that the ridge line portions are located close to each other, a first plane of one prism faces a second plane of another prism, and a third plane faces outward. Each of the two dichroic mirrors is constituted of a dielectric multilayer film provided between the first plane of one prism and the second plane of another prism. The outermost layer of a dielectric layer constituting the dielectric multilayer film is provided in contact with each of the first plane of the one prism and the second plane of the other prism.

Abstract: In an image generation unit, a light emitting part is formed using a self-emitting OLED device, and thereby, high-contrast images can be formed and the life of the light emitting part and the life of the virtual image display apparatus are extended. Even when the light emitted in the light emitting part has deviation in color balance, a half-mirror layer that has light transmissivity and realizes see-through vision is a reflection film having wavelength dependence, and thereby, a uniform color balance of image lights is achieved and images in good conditions are visually recognized.

Abstract: A dichroic prism synthesizes display light emitted from a plurality of display panels, and a plate-shaped light guiding section guides the synthesized light to a light-emitting section. In the display light emitted from the respective pixels of the display panel, although a radiation angle of an effective luminous flux which reaches the eye of an observer is large in a direction corresponding to the vertical direction, a range of incident angle of intersecting effective luminous fluxes to the dichroic mirror is small.

Abstract: Provided are an optical unit and a display device that can appropriately perform reflection and transmission of image light emitted from a panel provided with a light emitting element, over a wide wavelength region in a dichroic mirror. The optical unit includes a first panel, a second panel, and a third panel arranged facing a first incident surface, a second incident surface, and a third incident surface of a dichroic prism, respectively, and each of the first panel, the second panel, and the third panel emits unpolarized image light. A polarization element is arranged between the first panel and the dichroic prism, and first image light emitted from the first panel is incident on the dichroic prism as linearly polarized light. A first dichroic mirror has polarization separation characteristics in addition to transmittance-wavelength characteristics.

Abstract: An optical element includes a first translucent member that contains a resin material and a half mirror film formed on a surface of the first translucent member. The half mirror film includes a silver film, a first dielectric multilayer film positioned between the silver film and the first translucent member, and a second dielectric multilayer film positioned on an opposite side of the silver film than the first translucent member. The first dielectric multilayer film includes a first aluminum oxide film in contact with the silver film, and a titanium oxide film in contact with the first aluminum oxide film on the first translucent member. The second dielectric multilayer film includes a zirconium oxide-based dielectric film and a second aluminum oxide film in contact with the zirconium oxide-based dielectric film. One of the second aluminum oxide film and the zirconium oxide-based dielectric film is in contact with the silver film.

Abstract: An encoder includes a light emitting portion emitting light, an optical element portion splitting the light into a first beam and a second beam, an optical scale receiving the first beam and the second beam from the optical element portion, and a light receiving portion receiving the first beam and the second beam from the optical scale and outputting a signal in accordance with intensity of the received light, in which the optical element portion includes a prism on which the light is incident, a beam splitter disposed on the prism and splitting the light incident on the prism into the first beam heading for the optical scale and the second beam heading for an inside of the prism, and a first mirror portion disposed on the prism and reflecting the second beam from the beam splitter toward the optical scale.

Abstract: A spectroscopic sensor that applies lights in a wavelength band containing plural wavelengths to an object and spectroscopically separates reflected lights or transmitted lights from the object using plural light band-pass filters that transmit the respective specific wavelengths and plural photosensor parts to which corresponding transmitted lights are input based on output results of independent photosensors. The spectroscopic sensor may be integrated in a semiconductor device or module by integration using a semiconductor process and downsizing may be realized.