An optical encoder 10 comprising: a light source 11; a splitter 12 splits a light from the light source 11, a light receiving unit 16; a scale 13 is arranged on a light path and movable in a measurement direction, a grating being arranged on a main surface of the scale; and an offset diffraction grating 14 includes a plurality of diffraction gratings arranged in the optical path from the splitter 12 to the light receiving unit 16, the plurality of diffraction gratings diffracting the split lights with different phases, wherein, the plurality of diffraction gratings 13 in the offset diffraction grating 14 are arranged in one plane parallel to the main surface of the scale and are offset each other in an offset direction orthogonal to the measurement direction, the light receiving unit 16 includes a plurality of light-receiving elements 16-11 to 16-23 arranged in the offset direction.

An optical sensing device configured to detect an object or features of the object is provided. The optical sensing device includes a structured light projector and a sensor. A structured light projector is configured to project a structured light to the object and includes a light source and at least one tunable liquid crystal diffractive optical element (LCDOE). The light source is configured to emit a light beam. The at least one tunable LCDOE is disposed on a path of the light beam and configured to convert the light beam into the structured light to form a structured light pattern on the object. The LCDOE is capable of controlling the structured light pattern by controlling voltage distribution to a liquid crystal layer in the LCDOE. The sensor is configured to sense a reflected light formed by the object reflecting the structured light. Besides, a structured light projector is also provided.

Disclosed is a four-dimensional (4D: 3D+time) multi-plane broadband imaging apparatus capable of recording 3D multi-plane and multi-colour images simultaneously. The apparatus comprises: one or more non-reentry quadratically distorted (NRQD) gratings (5) which can produce a focal length and a spatial position corresponding to each diffraction order, thus simultaneously transmitting wavefront information between multiple object/image planes (2) and a single image/object plane (7); a grism system (4) which can limit chromatically-induced lateral smearing by creating a collimated beam in which the spectral components are laterally displaced; a lens system (3) which is configured to adjust the optical path; and the optical detector(s) (6). In an optical system, the multiple object/image planes (2), the lens system (3), the grism system (4), the NRQD grating(s) (5), the optical detector(s) (6) and the single image/object plane (7) are located on the same optical axis (1). This simple, easy-to-use and compact apparatus can meet many different requirements and serve a large range of high throughput applications.

An eye tracker includes a lens, a beam splitter, a structured light source and an image capturing element. The beam splitter is disposed at one side of the lens. The structured light source and the image capturing element are disposed between the lens and the beam splitter. The structured light source is configured to emit a first light and project to the beam splitter. The first light is reflected to the lens from the beam splitter and passes through the lens to project to an eye. The first light is reflected from the eye to form a second light. The second light passes through the lens and projects to the beam splitter, and is reflected to the image capturing element from the beam splitter. A display is also provided.

A low-height projector assembly includes a biconvex lens, a converging lens, an aperture stop, and a beam-steerer between the biconvex lens and the converging lens. The biconvex lens has a principal plane, a focal length, and a first optical axis. The converging lens has a second optical axis laterally offset from the first. The beam-steerer is configured to steer light from the biconvex lens to the converging lens. An aperture-stop plane intersects the second optical axis and the aperture stop. On the second optical axis, at least one of a front surface and a back surface of the converging lens is between the aperture-stop plane and the beam-steerer. The axial chief ray's propagation distance from the principal plane to the aperture stop differs from the focal length by less than half the depth of focus of the biconvex lens.

Generally, techniques related to an optical computer system and use thereof are described. In an example, an optical computer system includes a multi-purpose optical device, an imager, and an image sensor. The multi-purpose optical device is configured for different purposes, such as for data storage and for compute operations. The configuration utilizes diffractive optical layers that include different diffraction elements. The imager displays an image to the multi-purpose optical device. The image encodes command-related data depending on the purpose to be invoked, such a data location for a data read or input for a compute command. Light of the image travels to the multi-purpose device and is diffracted from the diffractive optical layers. The diffracted light is detected by the image sensor that converts it into an output.

An image display device includes an image light generation unit configured to generate image light, a projection system optical unit configured to project the image light, a correction system optical unit configured to correct aberrations, a first diffraction element configured to deflect the image light incident on a first incident surface, and a second diffraction element configured to deflect the image light incident on a second incident surface. The projection system optical unit, the second diffraction element, the correction system optical unit, and the first diffraction element are arranged in this order in a direction of the image light emitted from the image light generation unit, and the image light deflected and dispersed into rays of respective wavelengths by the second diffraction element is focused by the first diffraction element.

Arrays of integrated analytical devices and their methods for production are provided. The arrays are useful in the analysis of highly multiplexed optical reactions in large numbers at high densities, including biochemical reactions, such as nucleic acid sequencing reactions. The devices allow the highly sensitive discrimination of optical signals using features such as spectra, amplitude, and time resolution, or combinations thereof. The devices include an integrated diffractive beam shaping element that provides for the spatial separation of light emitted from the optical reactions.

An optical sensing device configured to detect an object or features of the object is provided. The optical sensing device includes a structured light projector and a sensor. A structured light projector is configured to project a structured light to the object and includes a light source and at least one tunable liquid crystal diffractive optical element (LCDOE). The light source is configured to emit a light beam. The at least one tunable LCDOE is disposed on a path of the light beam and configured to convert the light beam into the structured light to form a structured light pattern on the object. The LCDOE is capable of controlling the structured light pattern by controlling voltage distribution to a liquid crystal layer in the LCDOE. The sensor is configured to sense a reflected light formed by the object reflecting the structured light. Besides, a structured light projector is also provided.

Arrays of integrated analytical devices and their methods for production are provided. The arrays are useful in the analysis of highly multiplexed optical reactions in large numbers at high densities, including biochemical reactions, such as nucleic acid sequencing reactions. The devices allow the highly sensitive discrimination of optical signals using features such as spectra, amplitude, and time resolution, or combinations thereof. The devices include an integrated diffractive beam shaping element that provides for the spatial separation of light emitted from the optical reactions.