Photonics Dictionary: H

Photography involving the recording of events that occur too fast to be perceived by the human eye or recorded by conventional photographic techniques. See high-speed movie camera; high-speed...

1. In a cathode-ray tube, the glow surrounding a bright spot that appears on the fluorescent screen as the result of the screen's light being reflected by the front and rear surfaces of the tube's...

1. The faintly hued ring that is seen to surround a light source viewed through fog or light clouds. The size of scattering particles determines the size of the ring. 2. The ring surrounding a...

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 test for spherical aberration, coma or astigmatism in which incident rays from a point source are isolated by small holes in a metal disc located close to the lens or mirror under test....

A filter, used in photography, that absorbs the ultraviolet and extreme blue violet radiation scattered by atmospheric haze.

The decrease in effect in developable density on a photographic plate formed by a second exposure to radiation having a longer wavelength, usually red or infrared.

A term used to describe a photograph, film or television picture where the values for black and white areas are at or near their limits, thereby giving the maximum degree of difference between them.

Extensive data storage in the form of bits, with the use of high-resolution photographic materials and optics, and generally a laser.

A shutter actuated by means other than mechanical springs for timings on the order of nanoseconds. The shutter is used in the photography of rapid moving objects or events.

A fish-eye lens designed to photograph cloud formations over the entire visible sky.

A camera system used to form a high-precision hologram of the subject on a photographic plate. It contains a high-power pulsed laser as the illuminating source.

A holographic camera, also known as a holographic imaging system or holographic recorder, is a specialized device used to capture 3D holographic images of objects or scenes. Unlike conventional...

A holographic grating is a type of diffraction grating that is produced using holographic recording techniques. It consists of a periodic structure of alternating transparent and opaque regions,...

The interferometric analysis of a complex object by utilizing the three-dimensional hologram. By causing a laser beam to diverge into two directions, one of which directly strikes a holographic...

A photographic recording of interference patterns between a plane wave and a spherical wave on a high-resolution photographic emulsion.

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 single housing that includes means of recording an image photographically and electronically.

That object distance at which a camera must be focused so that the far depth of field just extends to infinity. The near limit of the depth of field is then half the hyperfocal distance. For normal...

With respect to photography, the process used to increase the effective speed of an emulsion between manufacture and exposure.

A type of stereoscopic photography in which the distance between the two view points is greater than the average interpupillary distance. Therefore, the viewed image will appear to be half its size...