A head-mounted apparatus include an eyepiece that include a variable dimming assembly and a frame mounting the eyepiece so that a user side of the eyepiece faces a towards a user and a world side of the eyepiece opposite the first side faces away from the user. The dynamic dimming assembly selectively modulates an intensity of light transmitted parallel to an optical axis from the world side to the user side during operation. The dynamic dimming assembly includes a variable birefringence cell having multiple pixels each having an independently variable birefringence, a first linear polarizer arranged on the user side of the variable birefringence cell, the first linear polarizer being configured to transmit light propagating parallel to the optical axis linearly polarized along a pass axis of the first linear polarizer orthogonal to the optical axis, a quarter wave plate arranged between the variable birefringence cell and the first linear polarizer, a fast axis of the quarter wave plate being arranged relative to the pass axis of the first linear polarizer to transform linearly polarized light transmitted by the first linear polarizer into circularly polarized light, and a second linear polarizer on the world side of the variable birefringence cell.

A distance measuring device includes a light emitting unit that outputs a measurement light, a first polarization state control unit that controls a polarization state of the measurement light output from the light emitting unit, a second polarization state control unit that controls the polarization state of the measurement light of which a polarization state is controlled by the first polarization state control unit, and an optical path switching element that selects an emission direction of the measurement light of which a polarization state is controlled by the second polarization state control unit, in which the second polarization state control unit controls the polarization state of the measurement light so that the measurement lights are emitted from the optical path switching element in a plurality of the emission directions, and the optical path switching element receives a reflected light obtained by reflecting the emitted measurement light by an object.

Provided is an optical imaging system, adapted for presenting an image of a particle. The optical imaging system includes a collimated light source, a flow channel, and a telecentric lens. The collimated light source is adapted for emitting a parallel beam. The flow channel is arranged on the transmission path of the parallel beam and is adapted for allowing the particle to pass through. The telecentric lens is arranged on the transmission path of the parallel beam. The parallel beam passes through the flow channel before transmitted to the telecentric lens, and the telecentric lens is adapted for converging the parallel beam onto an imaging plane.

A method and arrangement for testing and/or correction of a weld (34, 36, 38) of a test object (26, 102), including alignment of an ultrasonic probe (16, 128) guided by a robot (100) on a target position of the weld (28, 30, 32), determination of the actual position (34, 36, 38) of the weld by means of an optical sensor (22, 130) and alignment of the ultrasonic probe (16) on the actual position, and measurement of the weld, where CAD data of the target position of the weld (28, 30, 32) is made available, on the basis of the CAD data of the weld the ultrasonic probe (16, 128) is aligned on the target position of the weld, and the ultrasonic probe is placed on the weld with controlled force after determination of the actual position (34, 36, 38) of the weld by means of the optical sensor (22, 130).

The present disclosure relates to a filter unit, a filter selection method, and an imaging device that allow continuously changing a transmittance of an ND filter and switching between filters to be performed more easily. A disk provided with a plurality of filters including an ND filter having a continuously variable transmittance is rotated to cause a filter corresponding to a rotational orientation of the disk among the plurality of filters provided on the disk to be arranged on an optical axis of incident light toward an image sensor. The present disclosure can be applied to, for example, a filter unit, an imaging device, electronic equipment, a filter selection method, a program, or the like.

A display panel and a display device thereof are provided. The display panel comprises a display module comprising a first substrate and a first polarizer, wherein a light-exiting surface of the display module is arranged on an outer side of the first polarizer; a fingerprint recognition module disposed on an outer side of the first substrate and comprising a fingerprint recognition layer and a second polarizer disposed on an inner side of the fingerprint recognition layer; and a light source disposed on an inner side of the first polarizer. The fingerprint recognition layer recognizes fingerprint based on fingerprint signal light. The first polarizer is engaged with the second polarizer, such that the fingerprint signal light is transmitted through the first polarizer and the second polarizer without a light intensity loss, and the second polarizer reduces the light intensity of fingerprint noise light.

In various embodiments, workpieces are processed, e.g., via welding or cutting, while the shape and/or one or more other parameters of the laser processing beam are altered. The shape and/or one or more other parameters of the laser processing beam may be varied based on one or more characteristics of the workpiece.

Provided are an image display unit and a head-mounted display where the size is small, the light utilization efficiency is high, and a decrease in image quality is small. The image display unit includes: an image display apparatus; a polarization diffraction element that diffracts light emitted from the image display apparatus; and a polarizing plate that allows transmission of the polarized light diffracted by the polarization diffraction element and absorbs light not diffracted by the polarization diffraction element, in which the polarization diffraction element is a polarization diffraction lens having a lens function, and in a case where a focal length of the polarization diffraction lens is represented by f and a distance between the image display apparatus and the polarization diffraction lens is represented by d, d≤f is satisfied.

Provided in the present invention is a project unit, which is used for projecting an image to a target area containing a target object, said image having a certain gradual change rule and being unique in a certain spatial range. Also provided are a corresponding photographing apparatus, an imaging device, and a processor. The technical solution used by the present invention uses the projection unit to project, to the target area, an image which has a certain gradual rule and which is unique in a certain spatial range, and a target object which projects such an image is photographed by means of a certain unit, thus avoiding repeated photographing and obtaining multiple images, and by means of combining relevant characteristics of the image, the accuracy of follow-up point cloud generation on a back-end processor is improved, while achieving good real-time performances.

The present invention provides a display device and a display control method of the display device, so as to improve transmittance of the light emitted from the display device itself in an indoor environment. A display device provided by the present invention includes a display panel and a quarter-wave layer disposed at a light outgoing side of the display panel, the display device further includes: a liquid crystal structure disposed at a side of the quarter-wave layer away from the display panel, the liquid crystal structure presenting a polarization state or a transparent state under different ambient light intensity conditions.