Photonics Dictionary

A 3D profile sensor, also known as a 3D profiling sensor or 3D depth sensor, is a technology that is used to capture and measure the three-dimensional shape or profile of an object or a scene. These...

The point to which the extension of the straight line, reaching from the sun to the observer's eye after penetrating the atmosphere of the Earth, is projected.

The actual width of a bevel rather than its width projected along the lens aperture.

An instrument for measuring the brightness (luminance) of a scene. It may be a spot meter, covering an area of a degree or less, or an averaging meter, covering a broad area of the scene. Brightness...

Two microscopes that are coupled on a common stand, the two images being projected side by side in the field of view of a single eyepiece for comparison.

A single positive lens or group of lenses used in a projection system to collect light from a source and cause it to illuminate evenly the object to be projected.

A large-scale, precise drawing of the contours of a perfect mechanical part, often with plus and minus tolerances drawn or indicated. For quality control decisions, enlarged images of mechanically...

An inspection device in which the profile of a mechanical part is projected onto a ground-glass screen at a precisely known magnification so that the shape of the part can be compared with a scale...

The number of separate images exposed by a cine camera in a second or the number illuminated by a cine projector in a second. By varying the number of images recorded per second, films can be created...

A technique used to create a series of interrelated holographic images that give an appearance of motion when projected in sequence. A flashing laser is used in both the recording and projecting of...

A camera tube similar in design to the iconoscope. However, the image formed in the image iconoscope is projected on a photocathode that emits photoelectrons to be focused on a material, forming the...

A type of geometrical distortion that brings about a trapezoidal display of a nominally rectangular picture. Usually produced when a picture is projected abnormally to the screen.

A technique that uses a solid-state laser and a detector to determine an object's relative distance to the system. The laser beam is projected onto the target and then reflected onto a detector...

Liquid crystal on silicon (LCoS) is a display technology that combines liquid crystal materials with silicon-based semiconductor technology to create high-resolution, high-quality images. LCoS...

Luminous flux emitted from a surface per unit solid angle per unit of area, projected onto a plane normal to the direction of propagation. Also known as brightness and luminous sterance.

A specific method for measuring the diameter of irregular shaped particles, Martin's diameter is the measured distance between opposite sides of a particle, and is measured transverse to the particle...

A device to modulate spatially a collimated coherent beam of light with input data in optical data processing. It uses a photocathode mounted on a microchannel plate, which amplifies an electron...

A small card (10 x 15 cm) that has been treated with a photographic emulsion to record and store the microimages of documents and graphic information projected on it by a microfilm camera. A...

A device used to view microfilmed documents where the image on film is projected, in magnified form, onto a rear projection screen for viewing.

Method for reducing laser speckle in which the object field comes from a real diffuse object or the reconstructed object field from a hologram. During recording of the image, an aperture is moved in...

A form of lens assembly used in a projection system to maximize efficiency and assure uniform illumination of the object being projected.

The large, usually flat surface onto which an image is projected for viewing. May be reflecting or transmitting (rear projection).

A television display system in which the television signal is converted to an image that is projected onto either a front or rear projection screen.

The process of microphotography that involves the reduction of the original at a ratio greater than 100 to 1. The process is usually accomplished by the use of a reduced-scale negative, which, in...