A system includes a laser emitting a laser beam, a beam expander expanding the laser beam, a beam splitter prism splitting the expanded laser beam into first and second split light beams, a liquid crystal box containing polymer-dispersed liquid crystal, first and second reflectors reflecting the first and second split light beams to the liquid crystal box, respectively, and an attenuator arranged on an optical path between the beam expander and the liquid crystal box. The attenuator gradually attenuates at least one of the laser beam, the expanded laser beam, the first split light beam, or the second split light beam along a first set curve. The first split light beam and the second split light beam form interference fringes at the liquid crystal box to expose the polymer-dispersed liquid crystal to form a polymer-dispersed liquid crystal holographic grating having a diffraction efficiency decreasing along a second set curve.

A transparent display panel and a transparent display device are disclosed. The transparent display panel comprises a color filter substrate, an electrode layer, a blue phase liquid crystal layer configured to modulate an incident collimated natural light, and a light guide plate. The color filter substrate comprises a black matrix and pixel regions which are surrounded by the black matrix and arranged in a matrix, and each of the pixel regions on the color filter substrate is provided with a light shielding part at a central position, and an opening region surrounded by the light shielding part and the black matrix. The light guide plate is provided with a light exit region on a side close to the blue phase liquid crystal layer, the light exit region is arranged to correspond to the light shielding part in position, and in case the electrode layer does not apply a driving voltage to the blue phase liquid crystal layer, the collimated natural light which passes through the light exit region is incident on the light shielding part and is blocked by the light shielding part. The electrode layer is configured to apply the driving voltage to the blue phase liquid crystal layer to form a liquid crystal grating, and the blue phase liquid crystal receives different driving voltages at different positions in one of grating periods of the liquid crystal grating, so that the collimated natural light is diffracted by the liquid crystal grating and exits through the opening region.

The present application relates to an optical film layer and a display device. The optical film layer comprises: an isotropic optical layer, a plurality of grooves being formed on one side of the isotropic optical layer; a single optical axis anisotropic optical layer, comprising a plate-shaped part and a plurality of convex structures which match the shape and size of the grooves and which are attached to one side of the plate-shaped part, the ordinary light refractive index of the single optical axis anisotropic optical layer is greater than that of the isotropic optical layer; a first grating layer, stacked on the side of the single optical axis anisotropic optical layer away from the isotropic optical layer or embedded in the side of the single optical axis anisotropic optical layer away from the isotropic optical layer.

The liquid crystal grating of the present disclosure may include a plurality of grating element groups for forming dark fringes and transparent fringes. The dark fringe of each grating element group may be arranged adjacent to a transparent fringe of a neighboring grating element group. Each grating element group may include a plurality of first grating elements and at least one second grating element arranged parallel to each other. At least one of the first grating elements is transparent so as to form the transparent fringe of the grating element group, and different first grating elements are enabled to be transparent so as to change positions of the transparent fringes. The second grating element is opaque, the first grating elements and the second grating element that are opaque may be used to form the dark fringes of the grating element group, and the second grating element may have a width greater than that of each of the first grating elements.

Disclosed herein are various improvements in optical switching engines. In one aspect, a range of switching engines includes various multiple bounce, multiple image devices, such as, for example, the Herriott Cell and the Robert Cell. In another aspect, liquid crystal spatial light modulators (SLMs) are used in the switching engine of an optical cross-connect. In another aspect, polarization gratings (PGs) are used in the switching engine. In another aspect, a switching engine includes a Fourier cell using SLMs with more than two states. Alternative imaging optics in a Fourier cell implementing a multiple-bounce, multiple image device are also disclosed.

A polarization recycling backlight and a multiview display employ a polarization-selective scattering feature configured to preferentially scatter out a first polarization component of guided light and a polarization conversion structure configured to convert a portion of a second polarization component of the guided light into the first polarization component. The polarization conversion structure includes a subwavelength grating.

An optical device includes a first waveguide that propagates light in a first direction; and a second waveguide including a first mirror, a second mirror, and an optical waveguide layer. The first mirror extends in the first direction and has a first reflecting surface, and the second mirror extends in the first direction and has a second reflecting surface. The optical waveguide layer is located between the first and second mirrors and propagates the light in the first direction. A forward end portion of the first waveguide is disposed inside the optical waveguide layer. In a region in which the first and second waveguides overlap each other when viewed in a direction perpendicular to the first reflecting surface, at least part of the first waveguide and/or at least part of the second waveguide includes at least one grating whose refractive index varies periodically in the first direction.

According to one embodiment, a display device includes a first arrangement layer and a second arrangement layer. The first layer includes a first pixel, a second pixel, and a third pixel are arranged periodically in one direction. The second layer is opposed to the first layer, and the second layer includes a first element, a second element, and a third element which are arranged periodically to correspond to the first pixel, the second pixel, and the third pixel, respectively, and separate emission light to light of wavelength corresponding to a first color, light of wavelength corresponding to a second color, and light of wavelength corresponding to a third color to be emitted on the first pixel, the second pixel, and the third pixel, respectively.

A lithography system for generating grating structures is provided having a multiple column imaging system located on a bridge capable of moving in a cross-scan direction, a mask having a grating pattern with a fixed spatial frequency located in an object plane of the imaging system, a multiple line alignment mark aligned to the grating pattern and having a fixed spatial frequency, a platen configured to hold and scan a substrate, a scanning system configured to move the platen over a distance greater than a desired length of the grating pattern on the substrate, a longitudinal encoder scale attached to the platen and oriented in a scan direction and at least two encoder scales attached to the platen and arrayed in the cross-scan direction wherein the scales contain periodically spaced alignment marks having a fixed spatial frequency.

A variable wavelength light source and an apparatus including the same are disclosed. The variable wavelength light source includes: a first waveguide; a second waveguide spaced apart from the first waveguide; a first optical amplifier including a first gain medium; and a second optical amplifier including a second gain medium that is different from the first gain medium.