Photonics Dictionary

A device small enough to be held in a hand that uses a magnifying lens and a translucent back to permit the viewing of photographic transparencies.

A viewer that uses the transmittance of polarized light through glass or a similar medium to examine strained regions. See polariscope.

The angle subtended by an object, determined by the size of the object and its distance from the viewer.

Unified notation for specification of reflectance in terms of both incident- and reflected-beam geometry; i.e., the ratio of reflected radiance in direction toward the viewer to the irradiance in...

Able to rotate the plane of polarization of a transmitted, plane-polarized light beam clockwise as seen by a viewer looking in the same direction as the traveling light. Also called dextrorotary; the...

The area in a 2-D or 3-D microdisplay viewer within which the eye can move and still see the entire image.

High dynamic range (HDR) refers to a technology that allows for a broader and more dynamic range of luminosity in visual content, such as images or videos. It is particularly associated with displays...

Holography is a technique used to capture and reconstruct three-dimensional images using the principles of interference and diffraction of light. Unlike conventional photography, which records only...

A mirage that consists of an image of an object appearing below its true position as the result of abnormal refraction by the atmosphere between the object and the viewer. It is the opposite of a...

Also referred to as differential interference contrast (DIC) microscopy; Nomarski microscopy is a unique form of microscopy especially suited for the evaluation of surface quality and defects as well...

Also referred to as a funduscope, an ophthalmoscope is a specialized instrument used by ophthalmologists for observing and photographing the fundus (interior) of the eye which includes the retina,...

Ray tracing is a rendering technique used in computer graphics to simulate the way light interacts with objects in a scene. It involves tracing the path of rays of light as they travel through a...

A hologram that is illuminated by a source from the viewer's side.

A figure of merit corresponding to the amount of light seen by a viewer through binoculars. A higher number indicates a brighter image in low-light situations. The relative brightness value is...

In field-sequential color television, the rotating tricolor disc placed between the subject and the lens, or between the picture tube and the viewer.

An exaggerated depth appearance in stereo photographs caused by the lenses in the camera being farther apart than the eyes of the viewer.

A form of liquid crystal in which the 90° twist of the twisted nematic phase has been increased to 180° or more, resulting in higher contrast and a wider viewer angle in the display.

A hologram that is illuminated by a source opposite the viewer.