The range-finding apparatus (1) includes an optical receiver (110), a light source unit (200), a converter (134), and a calculation unit (300). The optical receiver (110) receives light to output a pixel signal. The light source unit (200) projects light with a first irradiation pattern in a first period and projects light with a second irradiation pattern in a second period. The converter (134) sequentially converts the pixel signal bit by bit using binary search to output a first digital signal and a second digital signal, the first digital signal being output by performing the conversion with a first bit width in the first period, the second digital signal being output by performing the conversion with a second bit width in the second period, the second bit width being less than the first bit width. The calculation unit (300) calculates a distance on the basis of the first digital signal and the second digital signal.

The range-finding apparatus (1) includes a light source (200), an optical receiver (1103), a setting unit (100), a detector (1100), and a calculation unit (300). The light source (200) projects light with a first irradiation pattern in a first period and projects light with a second irradiation pattern in a second period. The optical receiver (1103) receives light to output a pixel signal. The setting unit (100) sets a reference signal on the basis of the pixel signal in the first period. The detector (1100) detects whether or not the pixel signal varies from the reference signal by a first value or more in the second period and outputs a first detection signal indicative of a result obtained by the detection. The calculation unit (300) calculates a distance to a to-be-measured object using the first detection signal.

Disclosed is a method and associated apparatus for measuring a characteristic of interest relating to a structure on a substrate. The method comprises calculating a value for the characteristic of interest directly from the effect of the characteristic of interest on at least the phase of illuminating radiation when scattered by the structure, subsequent to illuminating said structure with said illuminating radiation.

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.

To measure a three-dimensional shape of a measurement target object at high speed, an information processing method includes acquiring a captured image captured by an imaging apparatus in a state where a pattern is projected onto the measurement target object, the pattern including a plurality of lines, identification information arranged on or between the lines to identify the lines, and a feature arranged between a plurality of the lines, identifying each line included in the captured image by acquiring a correspondence between each line included in the projected pattern and each line included in the captured image, determining a second region in the pattern corresponding to a first region between the lines in the captured image, and deriving a distance of the measurement target object by acquiring a correspondence between the first region and the determined second region.

One variation of method includes: serving setup frames to a projector facing a scene; at a peripheral control module comprising a camera facing the scene, recording a set of images during projection of corresponding setup frames onto the scene by the projector and a baseline image depicting the scene in the field of view of the camera; calculating a pixel correspondence map based on the set of images and the setup frames; transforming the baseline image into a corrected color image—depicting the scene in the field of view of the camera—based on the pixel correspondence map; linking visual assets to discrete regions in the corrected color image; generating augmented reality frames depicting the visual assets aligned with these discrete regions; and serving the augmented reality frames to the projector to cast depictions of the visual assets onto surfaces, in the scene, corresponding to these discrete regions.

A projection system includes an invisible light projector, a background member, an imaging unit, an image generator, and a visible light projector. The invisible light projector projects a predetermined invisible light image onto the object via invisible light. The background member is disposed behind the object in a direction of the invisible light emitted from the invisible light projector. The imaging unit captures an image of the invisible light projected from the invisible light projector. The image generator measures a shape of the object based on the image captured by the imaging unit to generate image data showing image content for projection onto the object in accordance with the measured shape. The visible light projector projects the image content shown by the image data onto the object via visible light. The background member has a light shielding surface that does not diffusely reflect the invisible light incident thereon.

Dynamic digital fringe projection (DDFP) techniques for measuring warpage. The DDFP technique generates a dynamic fringe pattern, in which a proper fringe intensity distribution is dynamically determined based on the surface reflectance of an unpainted sample in order to obtain better fringe image contrasts. The DDFP technique includes the automatic segmentation method to segment the chip package and PWB regions in an unpainted PWB assembly PWBA image. It also includes calibration methods to compensate the mismatches in coordinates and intensities between the projected and captured images.

A projection system includes a plurality of projection devices configured to perform position measurement and projection on a target object. Each of the projection devices includes: an invisible light projection unit configured to project invisible measurement light onto the target object; a light receiving unit configured to receive reflection light of the measurement light, the reflection light being reflected from the target object; a computing unit configured to calculate position information of the target object on the basis of the reflection light of the measurement light; and a visible light projection unit configured to project a visible light video content on the basis of the position information of the target object. A first projection device and a second projection device of the plurality of projection devices project the measurement light at different projection timings.

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.