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.

Provided are a signal source space sensing method and apparatus, and an active sensing system. The method includes: a controller controls a signal transmitter to transmit a first signal to an object to be tested; the controller controls a signal receiver to receive a second signal, which is obtained after the first signal is transmitted by the object; the controller determines a coordinate relationship between the spatial position of said object and a signal source space according to the first signal and the second signal, wherein the signal source space is a coordinate space where the first signal transmitted by the signal transmitter is located; and the controller maps the second signal back to the signal source space according to the coordinate relationship between the spatial position of the object and the signal source space, to obtain a signal source space signal so as to reconstruct a sensing signal.

The present disclosure is related to a system and a method for 3D shape measurement of a freeform surface based on high-speed deflectometry using composite patterns. More particularly, a system for profile measurement based on high-speed deflectometry using composite patterns includes: a composite pattern generation part to project a composite pattern generated by synthesizing patterns having different frequencies to a measurement object; a detector to acquire images of a deformed composite pattern reflected from the measurement object; and a phase acquisition part to acquire wrapped phases by each frequency from the composite pattern and unwrapped phases from the respective wrapped phases.

A three-dimensional measurement device measures the three-dimensional shape of an object or information indicating a shape thereof based on event data. A stripe pattern is projected from the projection unit to the object. The object is optically imaged by an imaging unit and an image based on event data is acquired. The event data, which are outputted from the image sensor, include two-dimensional point data that specifies the positions of pixels corresponding to the pixels that had luminance changes responsively to the stripe pattern projected. Based on the event data, an image of the object is obtained. The image sensor outputs positive luminance change event data when brightening luminance changes and negative luminance change event data when darkening luminance changes. The measurement unit obtains luminance information based on a time difference between output of event data of positive luminance changes and output of event data of negative luminance changes.

A deflectometry device comprising a kinematic spot part holder, a display, an imaging optic, a stop, and a camera imaging assembly including a camera lens and a camera having a detector. Additionally is described, a deflectometry device that is part of a deterministic finishing machine comprising a display, an imaging optic, a stop, and a camera imaging assembly including a camera lens and a camera. Additionally, a method for characterizing material removal created by a deterministic finishing machine is provided.

A measuring device includes a projector, a camera and a calculation device. The projector projects, on a target object, first stripe pattern light having a first period, second stripe pattern light having a second period, and third stripe pattern light having a third period. A relation of the periods is the first period<the second period<the third period. The camera captures an image of the first stripe pattern light, an image of the second stripe pattern light, and an image of the third stripe pattern light. The calculation device performs a phase analysis of luminance with a phase shifting method for the image of the first stripe pattern light, the image of the second stripe pattern light, and the image of the third stripe pattern light, and calculates a height of the target object based on obtained phase analysis results.

A method of determining dimensional information of a target surface includes generating a first point cloud corresponding to a first plurality of reconstructed surface points of the target surface generated by a first imaging system-illumination source pair of a phase profilometry system; generating a second point cloud corresponding to a second plurality of reconstructed surface points of the target surface generated by a second imaging system-illumination source pair of the phase profilometry system; generating an initial estimate of the target surface based on the first and second point clouds; and refining the initial surface estimate using positions of the first and second point clouds and geometry of the first and second imaging system-illumination source pairs to generate a final point cloud.

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.

A system for projecting dots onto a three-dimensional image is configured to activate multiple pseudo-random dot projectors sequentially. Each pseudo-random dot projector includes an illumination source and a wavefront modulating element (WME) located along an optical axis in a path traversed by radiation produced by the illumination source. The system is configured to form images of dots in the projection plane along the optical axis. The system may also include controlling circuitry configured to perform a sequential projection operation on the plurality of pseudo-random dot projection systems to produce a temporal sequence of images and aggregate and process the temporal sequence of images to produce a high-resolution depth image of the three-dimensional surface.

An image inspection apparatus includes: an image capturing unit which captures images of an object; a transparent illumination unit which has a light-emitting surface which radiates light to the object and is configured to be able to control a light-emitting position on the light-emitting surface and a radiation direction of the light; and a control unit which is configured to control the image capturing unit and the illumination unit. The control unit causes the illumination unit to change the light-emitting position and the radiation direction, causes the image capturing unit to capture images of the object, identifies a light-emitting position and a radiation direction of the illumination unit when a measurement point of the surface of the object is illuminated from images of the object, and calculates a distance to the measurement point on the basis of the identified light-emitting position and the identified radiation direction.