An optical device includes an array of light-emitting elements, including a first subset of light-emitting elements and a second subset of light-emitting elements. The first subset of light-emitting elements is configured to emit light having wavelength L.sub.1. The device includes a high refractive index material selectively disposed on the second subset of light-emitting elements and an array of optical elements positioned so as to be illuminated by the first subset of light-emitting elements and by the second subset of light-emitting elements. The optical elements are regularly arranged in a common plane at a pitch P, the common plane is located a distance D from the array of light-emitting elements, and P.sup.2≈2L.sub.1D/N, N being an integer greater than or equal to 1.

A structured-light scanning system with thermal compensation includes a structured-light projector that generates a predetermined projected pattern of light, which is then projected onto and reflected from an object, thereby resulting in a reflected pattern of light; an image sensor that captures the reflected pattern of light; and a digital processing unit that generates a depth map according to the reflected pattern of light and a compensated projected pattern associated with a current temperature.

A position detection system detects a position of an object by using a plurality of frames, each of the plurality of frames being divided into a plurality of subframes. The position detection system includes: a projector configured to project a plurality of gray code patterns having different gray code values in an order of ascending and then descending or descending and then ascending of the different gray code values, each of the plurality of gray code patterns corresponding to a corresponding one of the plurality of subframes, each of the different gray code values being a power of two; an imaging device configured to generate a captured image by, for each of the plurality of subframes, imaging the object on which the plurality of gray code patterns are projected; a controller configured to estimate the position of the object based on the captured image.

A switchable fringe pattern illuminator includes an optical path switch configured to receive light and dynamically control an amount of light that is provided to a first waveguide and an amount of light that is provided to a second waveguide. A first projector configured to generate a first fringe pattern using light from the first waveguide. The first fringe pattern illuminates a first portion of a target area. A second projector configured to generate a second fringe pattern using light from the second waveguide. The second fringe pattern illuminates a second portion of a target area. The illuminator may be part of a depth camera assembly (DCA). The DCA is configured to capture images of a portion of the target area. The DCA is further configured to determine depth information for an object in the target area based in part on the captured images.

The invention refers to a lighting device comprising at least one light emitting diode (LED). The object to provide a lighting device that is capable of providing a light pattern for illuminating an object in 3D imaging, wherein the lighting device is simple and cost-effective to manufacture, while the lighting device may in addition have a very small form factor, is solved in with a lighting device comprising: at least one LED for emitting light towards a light-emitting side; a first grating with a regular pitch having light-blocking sections and light-permeable sections; wherein the first grating is arranged on the light-emitting side to block the passage of light at the light-blocking sections, such that the light passing the light-permeable sections is capable to illuminate an object with a line pattern. The invention further corresponds to a method for producing a lighting device and the use of a lighting device.

A method for detecting demineralization of a tooth substance, including the steps of irradiating (S101) a structured light pattern onto the tooth substance; detecting (S102) a light intensity of the light pattern remitted from the volume of the tooth substance; and determining (S103) demineralization of the tooth substance based on the detected light intensity.

A depth camera assembly (DCA) for depth sensing of a local area includes a structured light generator, an imaging device, and a controller. The structured light generator illuminates the local area with a structured light pattern. The structured light generator includes a programmable diffractive optical element (PDOE) that generates diffracted scanning beams using optical beams. The PDOE functions as a dynamic diffraction grating that dynamically adjusts diffraction of the optical beams to generate the diffracted scanning beams of different patterns. The diffracted scanning beams are projected as the structured light pattern into the local area, wherein the structured light pattern is dynamically adjustable based on the PDOE. The imaging device captures image(s) of at least a portion of the structured light pattern reflected from object(s) in the local area. The controller determines depth information for the object(s) based on the captured image(s).

A three-dimensional shape measuring apparatus includes a stage that includes a translation stage part having a placement surface on which a measurement object is placed and capable of translating the placement surface; an illuminator that includes independently controllable and two-dimensionally-arranged projection devices, and illuminates the measurement object, which is placed on the stage, with measuring light having a predetermined projection pattern having alternating light-and-dark intervals; a photoreceptor that receives measuring light reflected by the measurement object illuminated by the illuminator, and to generate a projection pattern image; and a movement controller that controls the translational movement of the translation stage part by a moving pitch smaller than the minimum width of the projection pattern which can be projected on the stage by independently controlling the projection devices of the illuminator.

A system for structured light depth computation using single photon avalanche diodes (SPADs) is configurable to, over a frame capture time period, selectively activate the illuminator to perform interleaved structured light illumination operations. The interleaved structured light illumination operations comprise alternately emitting at least a first structured light pattern from the illuminator and emitting at least a second structured light pattern from the illuminator. The system is also configurable to, over the frame capture time period, perform a plurality of sequential shutter operations to configure each SPAD pixel of the SPAD array to enable photon detection. The plurality of sequential shutter operations generates, for each SPAD pixel of the SPAD array, a plurality of binary counts indicating whether a photon was detected during each of the plurality of sequential shutter operations.

This disclosure relates to optical three-dimensional (3D) measurement, and more particularly to a large-depth-range 3D measurement method, system, and device based on phase fusion. Sinusoidal fringes corresponding to multiple high-frequency binary fringe patterns varying in stripe width, a middle-frequency binary fringe pattern, and a low-frequency binary fringe pattern are formed and then projected onto a to-be-measured object. After modulated by height of the object, the sinusoidal fringes are collected, and wrapped phases of the collected sinusoidal fringes are calculated to determine absolute phases of high-frequency sinusoidal fringes. Phase errors of a high-frequency sinusoidal fringe under different fringe widths are calculated according to the defocusing degree. An optimal absolute phase is selected based on the phase errors for the large-depth range 3D measurement.