An optical device of the present disclosure includes a first light guide body including a first light-incident portion provided with a first incidence-side diffraction element, and a second light guide body including a second light-incident portion provided with a second incidence-side diffraction element, wherein the second light guide body, when light is caused to enter the first light-incident portion, is disposed at a position at which a part of the light passing through the first light guide body enters the second light-incident portion, and the second incidence-side diffraction element is an element that diffracts light of monochromatic color at a smaller angle than the first incidence-side diffraction element does, when the light of monochromatic color is caused to enter at a same angle.

A light source module and a display device are provided. The light source module includes a light-emitting element, a light-guiding plate, and a filter. The light-emitting element includes a light-emitting surface. The light-guiding plate includes a light-incident surface, and the light guide plate is disposed such that the light-incident surface faces the light-emitting surface. The filter is disposed between the light-emitting surface and the light-incident surface, and a center wavelength of a reflection band of the filter falls in a range of 570 nm to 590 nm. The light-emitting element emits a first light having a first color temperature from the light-emitting surface. The first light is filtered into the second light having a second color temperature after it passes through the filter. The light-incident surface of the light-guiding plate receives the second light. The first color temperature is lower than the second color temperature.

Provided is an optical element that can display a clear image having no blurriness in AR glasses or the like. The optical element includes: a substrate; and a laminate that is provided on the substrate and where a plurality of liquid crystal layers obtained by aligning a liquid crystal compound are laminated, in which the liquid crystal layers have a liquid crystal alignment pattern in which a direction of an optical axis derived from the liquid crystal compound changes while continuously rotating in at least one in-plane direction, and in at least one of the liquid crystal layers, an arithmetic mean value of differences between maximum film thicknesses and minimum film thicknesses obtained by observing 10 cross-sections with a scanning electron microscope is 0.1 μm or less.

Example display devices include a waveguide configured to propagate visible light under total internal reflection in a direction parallel to a major surface of the waveguide. The waveguide has formed thereon an outcoupling element configured to outcouple a portion of the visible light in a direction normal to the major surface of the waveguide. The example display devices additionally include a polarization-selective notch reflector disposed on a first side of the waveguide and configured to reflect visible light having a first polarization while transmitting the portion of the visible light having a second polarization. The example display devices further include a polarization-independent notch reflector disposed on a second side of the waveguide and configured to reflect visible light having the first polarization and the second polarization, where the polarization-independent notch reflector is configured to convert a polarization of visible light reflecting therefrom.

An optical cable includes a single optical connector configured for insertion into an optical receptacle so as to receive optical signals at a plurality of different wavelengths from the optical receptacle, and multiple electrical connectors, configured for insertion into respective electrical receptacles. Each electrical connector includes a transceiver configured to convert the optical signals into electrical output signals for output to an electrical receptacle. The optical cable further includes a plurality of optical fibers, having respective first ends connected together to the single optical connector so as to receive the optical signals. Each of the optical fibers has a respective second end coupled to a respective one of the electrical connectors. Wavelength selection optics are associated with the optical fibers so that the transceiver in each of the electrical connectors receives the optical signals at a different, respective one of the wavelengths.

A light-guiding plate includes a resin base having a parallelism P of 5 μm or less per an area of 50×100 mm.sup.2.

An optical apparatus includes an image source, a relay optical system, and an optical processing system. The image source is configured to display an image. The relay optical system is configured to project the image displayed by the image source to the optical processing system, and to image at infinity. The optical processing system is configured to project incident light from the relay optical system in a same direction to at least two preset directions sequentially.

A wearable display apparatus comprises a control unit, a display unit, an optical transmission unit and a photoelectric detection unit. The control unit is configured to control the display unit to output a display image, the light transmission unit is configured to transmit a first part of light of the display image to human eyes, and transmit a second part of the light of the display image to the photoelectric detection unit, the photoelectric detection unit is configured to send a feedback signal to the control unit; and the control unit is configured to compensate for a drift of characteristics including brightness and color according to the feedback signal from the photoelectric detection unit.

Diffraction gratings provide optical elements in head-mounted display systems to, e.g., incouple light into or out-couple light out of a waveguide. These diffraction gratings may be configured to have reduced polarization sensitivity. Such gratings may, for example, incouple or outcouple light of different polarizations with similar level of efficiency. The diffraction gratings and waveguides may include a transmissive layer and a metal layer. The diffraction grating may comprises a blazed grating.

Provided is an illumination device that makes it possible to enhance utilization efficiency of light, and a display device that includes the illumination device. The illumination device includes: a light source that is configured to generate light of a first wavelength; a luminescent body that is configured to wavelength-convert the light of the first wavelength to light of a second wavelength, the second wavelength being different from the first wavelength; and a wavelength selective filter that is provided on a light-incident side of the luminescent body, the wavelength selective filter being configured to transmit the light of the first wavelength and to reflect the light of the second wavelength.