A meta-optical device and a method of manufacturing a metasurface are provided. The meta-optical device includes a substrate and a nanostructure, wherein the nanostructure includes a first portion and a second portion that differ in at least one of a diameter and a period, wherein a ratio of an etch depth of the second portion to an etch depth of the first portion is about 0.9 to about 1.1, and the nanostructure includes at least one of sulfur, fluorine, and fluorocarbon.

A metalens (wavefront control element) according to the present disclosure is a wavefront control element that controls a wavefront of incident light, and includes a plurality of metasurface regions. The plurality of metasurface regions are arranged in an array.

A device includes an array of light sources configured to emit light beams, and a metasurface including a plurality of nanostructures and configured to receive and deflect the light beams emitted by the array of light sources. The metasurface includes a plurality of regions. Nanostructures in different regions of the plurality of regions are configured to deflect center light rays (with peak intensity) of the light beams into different directions towards a target, such as display optics of a near-eye display. In some embodiments, nanostructures in each region of the plurality of regions are configured to deflect center light rays of light beams of two or more different colors into a same direction or similar directions towards the target.

A color display of an embodiment includes: an embossed layer; a high refractive index layer; and a protective layer, laminated in this order, wherein the high refractive index layer has a highest refractive index among these layers, the embossed layer includes a first region having a periodic structure with a period at least smaller than a center wavelength of visible light, a plurality of the first regions, each having a strip shape, are connected to each other at their longitudinal end sides, the first regions being offset from each other in a direction perpendicular to a longitudinal direction of the strip shape, as viewed via a display surface, and a periodic direction of the periodic structure is parallel to the longitudinal direction.

An optical element for introducing a predetermined phase delay into incident electromagnetic radiation. The optical element comprises a first layer and a second layer arranged in a propagation path of a portion of the electromagnetic radiation. The first layer comprises a transmission regions configured to introduce a first phase delay into the portion of electromagnetic radiation propagating therethrough. The second layer comprises a metasurface configured to introduce a second phase delay into the portion of electromagnetic radiation propagating therethrough. The metasurface comprises subwavelength sized structures .

A display device includes a display panel that emits light from a plurality of pixels arrayed at predetermined pixel array pitches and an optical film, placed over the display panel so as to allow passage of light from the plurality of pixels, that includes first and second optical functional parts differing in optical performance from each other. The first and second optical functional parts are arrayed at predetermined functional part array pitches. Assuming that p (μm) denotes the pixel array pitches, that q (μm) denotes the functional part array pitches, and that d (μm) denotes a distance in a face-to-face direction between surfaces of the pixels that face the optical film and a surface of the optical film that faces the pixels, q≤0.5p and tan(asin(0.7/q))<p/d hold.

A welding torch maintenance apparatus and a welding tip changer are described. The welding torch maintenance apparatus and the welding tip changing apparatus each comprise a first gripping means for fastening the welding torch/diffuser so that the nozzle/welding tip is aligned with the rotational axis, a second gripping means for holding the nozzle/welding tip, the second gripping means rotates about the rotational axis to remove the nozzle/welding tip, and moves along the rotational axis. A drive means is provided for rotating the second gripping means, and a lift system is provided for moving the second gripping along the rotational axis. The welding torch maintenance apparatus further includes a cleaning means which enters the nozzle at the distal end and cleans an interior of the nozzle.

Embodiments of the disclosed subject matter provide a device having a full-color organic light emitting device (OLED) display having a plurality of pixels, with each pixel having a plurality of sub-pixels and where no individual sub-pixel of the plurality of sub-pixels emits white light. The OLED display may be configured to operate with a luminance of at least 1,000 cd/m.sup.2 at the D65 or higher white point, and using not more than a 0.5 mA/cm.sup.2 drive current for a blue sub-pixel of the plurality of sub-pixels based on an overall active area of the full-color OLED display.

Provided is a structured light projector including a light source configured to emit light, and a nanostructure array configured to form a dot pattern based on the light emitted by the light source, the nanostructure array including a plurality of super cells each respectively including a plurality of nanostructures, wherein each of the plurality of super cells includes a first sub cell that includes a plurality of first nanostructures having a first shape distribution and a second sub cell that includes a plurality of second nanostructures having a second shape distribution.

A sub-wavelength grating optical film comprises a plurality of one-dimensional periodic grating units repeatedly arranged side by side. Each grating unit with a period of p comprises a first medium, a second medium, a third material, a fourth material, a fifth material, a sixth medium and a seventh medium, wherein the sixth medium serving as a substrate and the seventh medium serving as a covering layer are respectively arranged on bottom and top of each grating unit periodically arranged side by side. By controlling grating period and refractive index, incident blue-violet light meets condition that a diffraction angle in a layer with highest refractive index is smaller than 90 degrees; and by adjusting duty ratio of the grating and the thickness of each layer of material, transmitted light energy of the blue-violet light wave band is the lowest so that harmful blue-violet light is isolated.