Provided a display apparatus including an image forming apparatus configured to form an image, a projection optical system configured to project the image formed by the image forming apparatus, and a combining optical system configured to provide the image projected from the projection optical system combined with light emitted from an external landscape, wherein the combining optical system is configured to divide the image projected from the projection optical system into same images and focus the same images on different positions.

Provided a display apparatus including an image forming apparatus configured to form an image, a projection optical system configured to project the image formed by the image forming apparatus, and a combining optical system configured to provide the image projected from the projection optical system combined with light emitted from an external landscape, wherein the combining optical system is configured to divide the image projected from the projection optical system into same images and focus the same images on different positions.

A diffractive optical element (10) comprises a microstructure plane provided thereon with at least one microstructural pattern unit. The diffractive optical element (10) can receive a light beam emitted from a partitioned light source array (20) and project a light field on a target surface (OB), wherein the partitioned light source array (20) comprises a plurality of light source arrays (20-1, 20-2, ..., 20-n) spaced along a first direction, and the microstructural pattern unit is configured to be capable of diverging and light homogenization-modulating a light beam emitted from a light source in the plurality of light source arrays (20-1, 20-2, ..., 20-n) along the first direction such that light field regions projected by adjacent light source arrays (20-1, 20-2, ..., 20-n) on the target surface are adjoined or overlapped with each other in the first direction. In the embodiments of the invention, there are gaps between adjacent partitions. The light source partitions are lightened in turn. When each light source partition is lightened, only a region in the target light field corresponding to the partition is illuminated uniformly. Moreover, when all partitions are lightened together, the whole target light field is illuminated uniformly. There is no dark space caused by gaps between partitions, thereby realizing uniform illumination of partitions in the target light field.

A laser system includes a signal source configured to generate input pulses, a diffraction grating module configured to stretch and split the input pulses into a plurality of spectral channels, a set of phase control devices, each phase control device being configured for spectral phase control of a respective spectral channel of the plurality of spectral channels, a power amplifier array of amplifier modules, each amplifier module of the power amplifier array being configured to amplify a respective spectral channel of the plurality of spectral channels, a spectral combiner configured to spectrally combine the plurality of spectral channels via diffraction grating-based pulse compression, and a feedback controller coupled to the spectral combiner to provide feedback to the set of phase control devices for pulse shaping.

An eyepiece for projecting an image to an eye of a viewer includes a waveguide configured to propagate light in a first wavelength range, and a grating coupled to a back surface of the waveguide. The grating is configured to diffract a first portion of the light propagating in the waveguide out of a plane of the waveguide toward a first direction, and to diffract a second portion of the light propagating in the waveguide out of the plane of the waveguide toward a second direction opposite to the first direction. The eyepiece furthers include a wavelength-selective reflector coupled to a front surface of the waveguide. The wavelength selective reflector is configured to reflect light in the first wavelength range and transmit light outside the first wavelength range, such that the wavelength-selective reflector reflects at least part of the second portion of the light back toward the first direction.

An eyepiece includes a planar waveguide having a front surface and a back surface. The eyepiece also includes a grating coupled to the back surface of the planar waveguide and configured to diffract a first portion of the light propagating in the planar waveguide out of a plane of the planar waveguide toward a first direction and to diffract a second portion of the light propagating in the planar waveguide out of the plane of the planar waveguide toward a second direction opposite to the first direction and a wavelength-selective reflector coupled to the front surface of the planar waveguide. The wavelength-selective reflector comprises a multilevel metasurface comprising a plurality of spaced apart protrusions having a pitch and formed of a first optically transmissive material and a second optically transmissive material disposed between the spaced apart protrusions.

A diffractive beam expander device (EPE1) includes a first spectral filter region (C2a) and a second spectral filter region (C2b) to provide a first optical route for blue and green light (B, G), and to provide a second optical router for red light (R). The expander device (EPE1) includes a first Bragg grating region (BRGa) to enhance optical absorption of red light (R) in the first spectral filter region (C2a). The expander device (EPE1) includes a second Bragg grating region (BRGa) to enhance optical absorption of blue light (B) in the second spectral filter region (C2b).

A method of microscopy comprises collecting an emission light; symmetrically dispersing the collected emission light into a first order (“1.sup.st”) light and a negative first order (“−1.sup.st”) light using a grating; wherein the 1.sup.st light comprises spectral information and the −1.sup.st light comprises spectral information; capturing the 1.sup.st light and the −1.sup.st light using a camera, localizing the one or more light-emitting materials using localization information determined from both the first spectral image and the second spectral image; and determining spectral information from the one or more light-emitting materials using the first spectral image and/or the second spectral image; wherein the steps of localizing and obtaining are performed simultaneously. A spectrometer for a microscope comprises a dual-wedge prism (“DWP”) for receiving and spectrally dispersing a light beam, wherein the DWP comprises a first dispersive optical device and a second dispersive optical device adhered to each other.

A rainbow-free waveguide display, a near-eye display incorporating the rainbow-free waveguide, and methods of manufacturing the rainbow-free waveguide are provided. The display includes a waveguide display configured to direct image light to an eyebox plane having a length (L.sub.Eyebox) and to a user's eye. The waveguide display includes a waveguide combiner and an out-coupler grating, wherein the out-coupler grating has a grating period Λ.sub.OC such that all angles of incidence θ.sub.in of light from an external light source, result in diffracted angles θ.sub.out, that miss the user's eye.

A diffractive image combiner is provided, to increase an exit pupil dimension, thereby improving user experience. The diffractive image combiner includes a first diffractive optical element DOE and a second diffractive optical element DOE. The first diffractive optical element DOE is parallel to the second diffractive optical element DOE. A grating vector of a first incidence point in the first diffractive optical element DOE is the same as a grating vector of a second incidence point in the second diffractive optical element DOE. The first incidence point is used to convert an incident light ray that meets a Bragg condition into a first diffracted light ray and a first transmitted light ray. The first transmitted light ray is incident to the second incidence point. The second incidence point is used to convert the first transmitted light ray into a second diffracted light ray.