Disclosed is a phase-shifting phase measurement error correction method based on pixel tracing of object raster images. During traditional phase-shifting shape measurement, surface height information is represented by phase information. The nonlinearity of equipment inevitably causes errors of phase information calculated according to images captured by a camera. The method comprises: projecting, by projector, a special raster projection to resolve a pixel-tracing mapping relation; in a direction against a light path, determining the position of a point light source that illuminates any one image pixel in a captured image and is located in an imaging plane of the projector according to the pixel-tracing mapping relation; and finally, replacing distributed phase information in image pixels with ideal phases in point light sources to correct phase errors to improve the accuracy of phase-shifting shape measurement. Compared with existing methods, the method is easy to operate and high in efficiency and precision.

A three-dimensional measurement device performs three-dimensional measurement of a measured object using a phase shift method. The three-dimensional measurement device includes: an irradiator that irradiates the measured object with a predetermined light pattern having a light intensity distribution in a fringe shape; a control device that shifts a phase of the light pattern radiated from the irradiator in N different ways, where N is a natural number of not less than 3; and an imaging device that takes an image of the measured object irradiated with the light pattern. The control device executes three-dimensional measurement of the measured object by the phase shift method based on N different image data taken under the light pattern having the phase shifted in the N different ways.

Provided is an intraoral measurement device that enables high-accuracy profilometry with a simple device configuration using a prism.

Disclosed are a 3D scanner, an additive manufacturing system and an apparatus and method for identifying features of a 3D object manufactured in such a system. An apparatus comprises an optical projection assembly comprising a light source and an optical grating, for illuminating an object with first and second light patterns having different spatial frequencies, wherein the optical projection assembly provides a first light pattern in a first configuration of the optical projection assembly and provides a second light pattern in a second configuration of the optical projection assembly. An image capturing apparatus is used to capture images corresponding to reflections of the first and second light patterns from the illuminated object, and a processing unit is used to identify, from the captured reflections of the first and second light patterns, the effects of distortions in the reflected light patterns corresponding to features of the illuminated object.

Methods, systems, and apparatuses are provided for estimating a location on an object in a three-dimensional scene. Multiple radiation patterns are produced by spatially modulating each of multiple first radiations with a distinct combination of one or more modulating structures, each first radiation having at least one of a distinct radiation path, a distinct source, a distinct source spectrum, or a distinct source polarization with respect to the other first radiations. The location on the object is illuminated with a portion of each of two or more of the radiation patterns, the location producing multiple object radiations, each object radiation produced in response to one of the multiple radiation patterns. Multiple measured values are produced by detecting the object radiations from the location on the object due to each pattern separately using one or more detector elements. The location on the object is estimated based on the multiple measured values.

The techniques described herein relate to methods, apparatus, and computer readable media configured to determine parameters for image acquisition. One or more image sensors are each arranged to capture a set of images of a scene, and each image sensor comprises a set of adjustable imaging parameters. A projector is configured to project a moving pattern on the scene, wherein the projector comprises a set of adjustable projector parameters. The set of adjustable projector parameters and the set of adjustable imaging parameters are determined, based on a set of one or more constraints, to reduce noise in 3D data generated based on the set of images.

An apparatus and a method are provided. The apparatus includes a light source configured to project light in a changing pattern that reduces the light's noticeability; collection optics through which light passes and forms an epipolar plane with the light source; and an image sensor configured to receive light passed through the collection optics to acquire image information and depth information simultaneously. The method includes projecting light by a light source in a changing pattern that reduces the light's noticeability; passing light through collection optics and forming an epipolar plane between the collection optics and the light source; and receiving in an image sensor light passed through the collection optics to acquire image information and depth information simultaneously.

The imaging camera includes the high-sensitivity pixel with the spectral sensitivity characteristic having high sensitivity to a light of the wavelength to be irradiated to the solder (target), and the low-sensitivity pixel with the spectral sensitivity characteristic having low sensitivity to this light. This allows the pattern light reflected in the high-reflection area of the surface of the solder to be converted to an appropriate pixel value using the low-sensitivity pixel, while allowing the pattern light reflected in the low-reflection area of the surface of the solder to be converted to an appropriate pixel value using the high-sensitivity pixel. Namely, both the pattern lights reflected in the high-reflection area and the low-sensitivity pixel can be converted to appropriate pixel values. In this way, even if the solder has both the high-reflection area and the low-sensitivity pixel, acquisition of accurate pixel values is allowed for both of these areas.

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.

A method of putting a feature of interest on an object and an optical inspection system of a non-contact probe mounted on a positioning apparatus in a desired relationship. The method includes: a) identifying a target point of interest on the object to be inspected by arranging the non-contact probe and object at a first relative configuration at which a marker feature, projected by the non-contact probe along a projector axis that is not coaxial with the optical inspection system's optical axis, identifies the target point of interest; and b) subsequently moving the non-contact probe and/or object so as to put them at a second relative configuration at which the target point of interest and optical inspection system are at the desired relationship, in which the positioning apparatus is configured to guide such motion in accordance with the control path.