A waveguide illuminator includes an input waveguide, a waveguide splitter coupled to the input waveguide, and a waveguide array coupled to the waveguide splitter. The waveguide array includes an array of out-couplers out-coupling portions of the split light beam to form an array of out-coupled beam portions for illuminating a display panel. To reduce optical interference, the waveguide illuminator may have two interlaced waveguide arrays energized by two different light sources. Output polarizations of neighboring light pixels of a display illuminated with such waveguide illuminator may be orthogonal to each other. The frames to be displayed may be broken down into sequentially displayed sub-frames with interleaved pixels.

The present invention relates to a backlight unit for use in a display device. The backlight unit includes a circuit board, at least one light-emitting diode chip mounted on the circuit board, a plurality of reflection members arranged on the upper part of the light-emitting diode chip, and a light diffusing member. The light diffusing member has an incident surface on which light enters and an emitting surface from which light is emitted. The light diffusing member is arranged on the upper part of the circuit board. The plurality of reflection members are stacked on each other and reflect a part of light emitted from the upper surface of the light-emitting diode chip.

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.

An illumination device includes a plurality of light-emitting elements (LEEs); a light guide extending in a forward direction from a first end to a second end to receive at the first end light emitted by the LEEs and to guide the received light to the second end; an optical extractor optically coupled to the second end to receive the guided light, the optical extractor including a redirecting surface to reflect a first portion of the guided light, the reflected light being output by the optical extractor in a backward angular range, and the redirecting surface having one or more transmissive portions to transmit a second portion of the guided light in the forward direction; and one or more optical elements optically coupled to the transmissive portions, the optical elements to modify the light transmitted through the transmissive portions and to output the modified light in a forward angular range.

A near-eye display device comprises a pupil-expansion optic, a laser, a drive circuit coupled operatively to the first and second lasers, a spatial light modulator (SLM), and a computer. The SLM has a matrix of electronically controllable pixel elements and is configured to receive emission from the laser and to direct the emission in spatially modulated form to the pupil-expansion optic. Coupled operatively to the drive circuit and to the SLM, the computer is configured to parse a digital image, trigger the emission from the laser by causing the drive circuit to drive a periodic current through a gain structure of the laser, and control the matrix of pixel elements such that the spatially modulated form of the emission projects an optical image corresponding to the digital image, wherein the periodic current includes plural cycles of modulation driven through the gain structure while the optical image is projected.

The present disclosure provides an optical system and a near-eye display device. The optical system includes an optical waveguide and an eyepiece system. The eyepiece system is on a light incident side of the optical waveguide, and a light exit side of the eyepiece system is opposite to the light incident side of the optical waveguide so that light exited from the eyepiece system is incident on the optical waveguide. The eyepiece system includes a lens group which includes a first lens, a second lens and a third lens which are sequentially arranged in a direction parallel to the optical axis of the lens group; a side of the first lens away from the second lens is the light exit side of the eyepiece system, each of the first lens and the third lens has a positive focal power; and the second lens has a negative focal power.

A contamination sensor for an optical sensor observation window includes a source, two prisms, a detector, and a controller. The source can emit a collimated light beam at an incident angle that is greater than a critical angle of an interface between a fluid and the window. The window has a refractive index greater than the refractive index of the fluid. The prisms can direct the collimated light beam within the window such that the collimated light beam reflects within a contamination detection zone of the window. The detector can receive the collimated light beam. The controller can communicate with the source and detector. The controller can calculate an emission/detection ratio defined by a difference between an amount of light emitted by the source and an amount of light that passes from the source to the detector by a total internal reflectance of the window.

Time-multiplexed backlighting includes a time-multiplexed light source to provide a light beam having a first non-zero propagation angle during a first time interval and a second non-zero propagation angle during a second time interval. A time-multiplexed backlight includes a light guide configured to guide the light beam and a diffraction grating configured to coupled out a portion of the guided light beam with a different principal angular direction in each of the first time interval and the second time interval. A multiview display includes the time-multiplexed light source and a multibeam backlight to provide coupled-out light beams during each of the first and second time intervals, wherein the principal angular directions of the coupled-out light beams correspond to different view directions of the multiview display.

An optical device includes a first A deflecting member, a first B deflecting member, a first C deflecting member, a second A deflecting member, a second B deflecting member, and a second C deflecting member. Light emitted from an image forming device that enters the first A deflecting member and is emitted toward a pupil of an observer via the first B deflecting member and the first C deflecting member. Light emitted from the image forming device that enters the second A deflecting member is emitted toward the pupil of the observer via the second B deflecting member and the second C deflecting member. A direction of light deflected by the first A deflecting member that is orthogonally projected on a light guide plate is opposite a direction of light deflected by the second A deflecting member that is orthogonally projected on the light guide plate.

Various embodiments of waveguide devices are described. A debanding optic may be incorporated into waveguide devices, which may help supply uniform output illumination. Accordingly, various waveguide devices are able to output a substantially flat illumination profile eliminating or mitigating banding effects.