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.

To miniaturize an illumination device while meeting requirements of angle characteristics of a liquid crystal panel. A light source 31b is arranged above an outer end portion side of a liquid crystal panel 31d that is positioned radially outward of an illumination housing. A relative position between the liquid crystal panel 31d and the light source 31b is set such that light emitted from the light source 31b is incident within an effective angle range of the liquid crystal panel 31d.

Provided is a method for measuring surface characteristics of at least a portion of an object, including providing a light source; generating a first interference pattern on the at least a portion of the object; capturing an image of the first interference pattern; shifting the phase of the light source to generate a second interference pattern; capturing an image of the second interference pattern; filtering distortion from the interference patterns; extracting a wrapped phase of the at least a portion of the object based on the images; unwrapping the wrapped phase of the at least a portion of the object to generate an unwrapped phase; identifying a computed depth map distance to the at least a portion of the object; and fitting an ideal part to the computed depth map of the at least a portion of the object to measure the surface characteristics.

An apparatus for three-dimensional shape measurement is provided, including a projection device, an image capture device, and an image processing device. The projection device sequentially projects a plurality of structured light beams on a scene during a first projection period and a second projection period. The mean level of the structured light beams during the first projection period is the same as the mean level of the structured light beams during the second projection period, and the frequency of the structured light beams during the first projection period is different from the frequency of the structured light beams during the second projection period. The image capture device captures an image of the scene within the projection time of each of the structured light beams. The image processing device obtains a three-dimensional shape of a to-be-measured object in the scene according to the images.

A system can include an axis, a motor coupled with the axis and configured to rotate the axis, an optical modulator coupled with the axis and configured to be rotated by the axis, a lens element, a projection surface, a laser device configured to shine light through the optical modulator to project structured light onto the projection surface through the lens element, and a sensor configured to capture an image of a sample and structured light that is reflected from the projection surface and the sample surface. The system can also include a computing system having a synchronization module configured to phase lock the system by coordinating the laser device and the sensor and an analysis module configured to compute a three-dimensional (3D) object based on the structured light that is reflected from the projection surface and the sample surface.

A projection adjustment program which causes a computer to execute a process relating to adjustment of projection operations of a plurality of projection devices configured to perform position measurement and projection on a target object in a projection system including the plurality of projection devices. The process includes: causing a projection device to project measurement light onto the target object; causing an image capture device to receive reflection light of the measurement light, the reflection light being reflected from the target object; judging a connection relationship of a projection range of the projection device on a basis of the received reflection light of the measurement light; executing a process of the judging of the connection relationship on all processing target projection devices; generating projection position information indicating a connection relationship between projection ranges of the respective projection devices of the projection system; and displaying the generated projection position information on a display.

A three-dimensional shape measuring apparatus includes: a single projector device that projects a first light pattern whose luminance changes at a first cycle and a second light pattern whose luminance changes at a second cycle that is longer than the first cycle on a measured object; an image capture device that acquire an image of the measured object on which the first or second light pattern is projected; and an image processing device that processes the image acquired by the image capture device. The image processing device includes a relative phase value calculation unit that calculates a relative phase value on each part of the measured object based on a luminance value of an image of the measured object on which the first light pattern is projected, an absolute phase value calculation unit that calculates an absolute phase value on each part of the measured object based on a luminance value and the relative phase value of an image of the measured object on which the second light pattern is projected, and a three-dimensional coordinate calculation unit that calculates three-dimensional coordinates at each part of the measured object based on the absolute phase value.

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 three-dimensional (3D) imaging system includes a mobile device that has a display screen configured to display a series of patterns onto an object that is to be imaged. The mobile device also includes a front-facing camera configured to capture reflections of the series of patterns off of the object. The system also includes a controller that is configured to control a timing of the series of patterns that appear on the display screen and activation of the front-facing camera in relation to the appearance of the series of patterns.

Devices, methods and systems are disclosed that enable deflectometry on a wide array of objects, including convex and freeform optical components. One example deflectometry system includes a light source with a plurality of light emitting devices to illuminate an object under test with incident light, and a detector positioned to receive a reflected or transmitted light from the object under test. The deflectometry system further includes a movable stage for holding or securing the object under test. The movable stage can move in a translational or a rotational direction to cause the object under test to translate or rotate in a plurality of steps such that the light received at the detector encompasses a portion of a full illumination space surrounding the object, and the light received at the detector from all of the plurality of steps encompasses the full illumination space that contiguously surrounds the object under test.