According to one embodiment, a display device includes a display panel that includes a display portion including pixels and a non-display portion including an opening, an illumination device, and a color separation element provided between the display panel and the illumination device. The color separation element includes a first element overlapping the pixel and a second element overlapping the opening, the first element separates illumination light from the illumination device into light of a plurality of colors and irradiates the pixel with the light, and the second element separates illumination light from the illumination device into light of a plurality of colors and irradiates the opening with the light.

The present application provides a device for under-screen optical fingerprint-identification, which includes a display panel and a fingerprint-identification unit array, wherein the fingerprint-identification unit array is disposed inside the display panel, and includes a plurality of fingerprint-identification units and a plurality of diffraction grating layers. Additional optical structures can be excluded to prevent receiving large-angle interfered light signals by using the fingerprint-identification units having diffraction grating layers according to the present application, so that a thickness of the entire device can be greatly reduced.

A two-dimensional waveguide light multiplexer is described herein that can efficiently multiplex and distribute a light signal in two dimensions. An example of a two-dimensional waveguide light multiplexer can include a waveguide, a first diffraction grating, and a second diffraction grating disposed above the first diffraction grating and arranged such that the grating direction of the first diffraction grating is perpendicular to the grating direction of the second diffraction grating. Methods of fabricating a two-dimensional waveguide light multiplexer are also disclosed.

Disclosed is an array antenna which is capable of shifting a phase of light. According to one aspect of the present exemplary embodiment, an optical phase shifting array antenna includes: a receiving unit configured to distribute input light to a plurality of antenna element waveguides; a phase shifting unit configured to shift a phase of light propagated to each antenna element waveguide by applying heat to each antenna element waveguide; an output unit including a plurality of antenna elements, and configured to output the light, which is propagated to each antenna element waveguide after a phase is varied in the phase shifting unit, to each antenna element; and a base part configured to seat the receiving unit, the phase shifting unit, and the output unit.

According to one embodiment, a display device includes a display panel that includes a display portion including pixels and a non-display portion including an opening, an illumination device, and a color separation element provided between the display panel and the illumination device. The color separation element includes a first element overlapping the pixel and a second element overlapping the opening, the first element separates illumination light from the illumination device into light of a plurality of colors and irradiates the pixel with the light, and the second element separates illumination light from the illumination device into light of a plurality of colors and irradiates the opening with the light.

Methods, apparatus, devices, and systems for displaying three-dimensional objects by individually diffracting different colors of light are provided. In one aspect, an optically diffractive device includes: first and second diffractive components and a color-selective polarizer therebetween. The first diffractive component is configured to diffract a first color of light in a first polarization state incident at a first incident angle with a first diffraction efficiency at a first diffracted angle, and diffract a second color of light in a second polarization state with a diffraction efficiency substantially less than the first diffraction efficiency. The color-selective polarizer is configured to rotate the second polarization state of the second color of light to the first polarization state. The second diffractive component is configured to diffract the second color of light in the first polarization state with a second diffraction efficiency at a second diffracted angle substantially identical to the first diffracted angle.

Methods, apparatus, devices, and systems for displaying three-dimensional objects by individually diffracting different colors of light are provided. In one aspect, a system includes a display having a plurality of display elements and an optical device including at least two beam expanders configured to expand an input light beam in at least two dimensions to generate an output light beam to the display by diffracting the input light beam to adjust a beam size of the input light beam in the at least two dimensions, the input light beam including a plurality of different colors of light.

A display device includes a display panel including a display surface having a Lambertian light emission distribution, and a viewing angle modulator disposed on the display panel. The viewing angle modulator includes a first refractive layer including a diffraction structure on a surface, a refractive index conversion layer disposed on the first refractive layer and including an electro-optical material having a refractive index that changes when a voltage is applied to the electro-optical material, and a second refractive layer disposed on the refractive index conversion layer. The refractive index conversion layer includes a base layer, and an optical structure disposed on the base layer that changes a path of light incident on a surface facing the second refractive layer.

An object is to provide: an optical member with which an image display apparatus where multiple images are suppressed can be obtained; and an image display apparatus including the optical member. The optical member includes: a light guide element that includes a light guide plate, first and second incidence diffraction elements, and first and second emission diffraction elements; a wavelength selective retardation layer that functions as a retardation layer with respect to a specific wavelength range, the wavelength selective retardation layer changing a polarized state of light diffracted by the first or second emission diffraction element; and a polarizer, in which the first and second emission diffraction elements are polarization diffraction elements and diffract light components such that the diffracted light components are polarized light components having opposite properties, the first and second emission diffraction elements, the wavelength selective retardation layer, and the polarizer are provided to overlap each other in a main surface of the light guide plate, and the wavelength selective retardation layer is provided between the light guide element and the polarizer.

Methods, apparatus, devices, and systems for reconstructing three-dimensional objects with display zero order light suppression are provided. In one aspect, a method includes illuminating a display with light, a portion of the light illuminating display elements of the display, and modulating the display elements of the display with a hologram corresponding to holographic data to diffract the portion of the light to form a holographic scene corresponding to the holographic data, and to suppress display zero order light in the holographic scene. The display zero order light can include reflected light from the display.