Photonics Dictionary

An aperture located at an image plane of an optical system that determines the size and shape of the image.

A flanged or plain ring with a restricted aperture, located in an optical system at any of several points, that cuts off marginal light rays not essential to image formation. Diaphragms are used as...

Luminescence is the emission of light that occurs without the involved substance undergoing a significant increase in temperature. In other words, it is the production and emission of light by a...

A camera designed with a telecentric optical system and a narrow field of view; the telecentric optical system (placement of the system's stop at its focal point) ensures that the principal image...

A high-speed, narrow-field lens consisting of two achromats spaced about the aperture stop. Its uses include portrait photography and motion picture projection.

A camera that consists of a concave spherical mirror with an aspheric plate situated at the center of curvature of the mirror. The purpose of the plate is to correct the spherical aberration of the...

To reduce the size of a lens aperture, which increases the depth of field.

The image of the aperture stop, usually the objective lens, that is produced by the eye lens. When the exit pupil of the telescope coincides with the entrance pupil of the eye of the observer, the...

A time-to-amplitude converter (TAC) is an electronic circuit that converts a time interval between two events into an amplitude or voltage signal. TACs are commonly used in various scientific and...