To provide a display apparatus that can display an image at a wide angle of view while preventing the display apparatus from being made larger in size. The present technology provides a display apparatus that includes a light-emitting system that emits image light that includes a plurality of pieces of light of different wavelengths; a light guiding system that guides the image light emitted by the light-emitting system; and a light deflecting system that deflects the plurality of pieces of light included in the image light guided by the light guiding system, and causes the plurality of pieces of deflected light to be incident on an eyeball from different directions. The present technology makes it possible to provide a display apparatus that can display an image at a wide angle of view while preventing the display apparatus from being made larger in size.

A metalens and an optical system having the metalens. The metalens includes: a substrate capable of transmitting light in different wavelength bands; and a plurality of unit cells on the same surface of the substrate. The multiple unit cells are arranged in an array, the unit cells are regular hexagons and/or squares. A center position of each unit cell or each of the center position and vertex positions of each unit cell is provided with a nanostructure. The nanostructures are symmetrically arranged with respect to a first axis and a second axis respectively, and partial nanostructures obtained by dividing the nanostructures on the metalens along the first axis and the second axis are identical to each other. The first axis is perpendicular to the second axis, and both the first axis and the second axis are perpendicular to a height direction of the nanostructures.

A laser system for nonlinear pulse compression includes a laser source configured to generate laser pulses with a pulse energy of at least 50 mJ, a spectral broadening device for spectrally broadening the high-energy laser pulses using self-phase modulation, and a compression device including a grating compressor having at least two diffraction gratings and configured to compress the spectrally broadened high-energy laser pulses. The laser system is configured to generate a pulse duration of the high-energy laser pulses of less than 100 fs.

A diffractive beam expander for use in an augmented-reality display is disclosed. The device can include a optical substrate with a first diffractive optical element having a first diffractive grating disposed on one surface and a second diffractive grating disposed on the opposing surface. Portions of the first and second diffractive gratings overlap to define an in-coupling area configured to receive a beam of incoming light. The first diffractive optical element expands at least part of the received light beam by odd-order diffraction expansion in a first region and a second region and expands at least part of the received light beam by even-order diffraction expansion in a third region. The light components by the first diffractive optical element are then coupled into a second diffractive optical element, which is configured to out-couple at least part of the expanded diffracted light components to exit the substrate by diffraction.

A lens unit (120) shows longitudinal chromatic aberration and focuses an imaged scene into a first image for the infrared range in a first focal plane and into a second image for the visible range in a second focal plane. An optical element (150) manipulates the modulation transfer function assigned to the first and second images to extend the depth of field. An image processing unit (200) may amplify a modulation transfer function contrast in the first and second images. A focal shift between the focal planes may be compensated for. While in conventional approaches for RGBIR sensors contemporaneously providing both a conventional and an infrared image of the same scene the infrared image is severely out of focus, the present approach provides extended depth of field imaging to rectify the problem of out-of-focus blur for infrared radiation. An imaging system can be realized without any apochromatic lens.

An image pickup apparatus includes an image forming optical system which includes an aperture stop that sets an axial light beam, and a diffracting optical surface disposed at a position different from a position where the aperture stop is disposed, and an imager which is disposed on an image side of the image forming optical system, and has a light-receiving surface which is not flat and is curved to be concave toward the image forming optical system, wherein the diffracting optical surface satisfies the following conditional expression (1).

0.1<|DSD/TL|≦1.0  (1) where, TL denotes an actual distance on an optical axis of the image forming optical system, from a surface of incidence of the image forming optical system up to the light-receiving surface, DSD denotes an actual distance on the optical axis of the image forming optical system, from a position of the aperture stop up to the diffracting optical surface, and when a focal length of the image forming optical system is variable, conditional expression (1) is a conditional expression in a state at a wide angle end.

Provided is a metalens including a first metasurface including a plurality of first nanostructures disposed based on a first shape distribution, and a second metasurface spaced apart from the first metasurface at a distance greater than a central wavelength of a predetermined wavelength band, the second metasurface including a plurality of second nanostructures disposed based on a second shape distribution, wherein the metalens provides chromatic aberration for light in the predetermined wavelength band.

A diffractive optical element includes a first lens having a convex surface, a second lens having a concave surface, disposed in such a manner that the concave surface of the second lens faces the convex surface of the first lens, and a diffraction grating section formed between the first and the second lenses and having positive optical power through diffraction. The diffraction grating section includes a first diffraction grating and a second diffraction grating disposed in this order from a side closer to the first lens; the second diffraction grating has a refractive index larger than that of the first diffraction grating, and an inner diameter of a grating wall surface of the diffraction grating section decreases as approaching to the second lens from the first lens.

A method for assessing the similarity between a power profile of a manufactured optic device and a nominal power profile upon which the power profile of the manufactured optic device is based. The method comprises measuring the power profile of manufactured optic device, identifying a region of interest from the measured power profile of manufactured optic device, and applying an offset to the measured power profile to substantially minimize a statistical quantifier for quantifying the similarity between the nominal power profile and the offset measured power profile. The method further comprises comparing the offset and the statistical quantifier to predefined quality control metrics, determining whether the measured power profile meets the predefined quality control metrics based, at least in part on the comparison. In exemplary embodiments, the method may further comprise determining whether to associate the manufactured optic device with another nominal power profile, if the measured power profile does not meet the predefined quality control metrics.

Disclosed are an apparatus and method for providing additional degrees of freedom for diffraction gratings of an output waveguide in a near-eye display device. The near-eye display device includes an imager to generate an image based on light from a light source. The device further includes a waveguide to input a light wave representing the image received from the imager and to output the light wave representing the image toward an optical receptor of a user. The waveguide includes a plurality of diffractive optical elements (DOEs) in a common light path from an input of the waveguide to an output of the waveguide. The DOEs include a plurality of periodic diffraction patterns. Each of the periodic diffraction patterns is represented by a diffraction pattern vector. The periodic diffraction patterns are determined such that a vector summation of the diffraction pattern vectors equals zero.