Photonics Dictionary: Z

A highly flame-retardant material used to jacket fiber optic cables, especially on shipboard applications.

The intensity regulation of a cathode-ray tube by alteration of the grid-cathode voltage.

A technique for determining the nonlinear optical properties of a sample material by moving the sample through a focused laser beam and measuring changes in the beam's characteristics, such as...

A type of semiconductor diode used in voltage-limiting circuits; when voltage reaches a certain value, the device becomes a conductor.

The introduction of a filter into an imaging system to implement a phase contrast for an intensity mapping of a pure phase image.

The removal of the zero-order component of the Fourier spectrum distribution of an object with a small, opaque absorber or reflector in the Fourier plane, to produce images that appear bright on a...

A quarter- or half-wave retarder made from two plates of quartz, mica or polymer with their fast axes crossed; the difference in thickness between the two plates determines the retardance. Zero-order...

A factor that, when multiplied by the average candlepower emitted by a light source in a specified angular zone, reveals the lumens in the zone.

Also known as zonal axis. The axis positioned through the center of a crystal that is parallel to a zone edge.

A plate of glass, usually a photograph, on which there is a central spot surrounded by concentric annular zones, alternately opaque and transparent, the radii of the boundaries between the zones...

1. In a polished surface, concentric waves that appear as zones in Newton's rings when a test glass is applied. 2. An arrangement of crystal faces that come together in a series of edges, all of...

To control, by magnifying or reducing, the size of a televised image, either electronically or optically.

An optical system of variable focal length, the focal plane remaining in a fixed position. This result is achieved by moving some of the components of the system along the lens axis, other components...