illuminated aperture
11Art, Antiques, and Collections — ▪ 2003 Introduction In 2002 major exhibitions such as Documenta 11 reflected the diverse nature of contemporary art: artists from a variety of cultures received widespread recognition for work ranging from installation to video to painting …
12Parabolic antenna — A parabolic satellite communications antenna at Erdfunkstelle Raisting, the biggest facility for satellite communication in the world, in Raisting, Bavaria, Germany. It has a Cassegrain type feed. A parabolic antenna is an antenna that uses a… …
13photography, technology of — Introduction equipment, techniques, and processes used in the production of photographs. The most widely used photographic process is the black and white negative–positive system (Figure 1 >). In the camera the lens projects an image of… …
14Clutter (radar) — Clutter is a term used for unwanted echoes in electronic systems, particularly in reference to radars. Such echoes are typically returned from ground, sea, rain, animals/insects, chaff and atmospheric turbulences, and can cause serious… …
15motion-picture technology — Introduction the means for the production and showing of motion pictures. It includes not only the motion picture camera and projector but also such technologies as those involved in recording sound, in editing both picture and sound, in… …
16Confocal laser scanning microscopy — (CLSM or LSCM) is a technique for obtaining high resolution optical images with depth selectivity.[1] The key feature of confocal microscopy is its ability to acquire in focus images from selected depths, a process known as optical sectioning.… …
17microscope — /muy kreuh skohp /, n. 1. an optical instrument having a magnifying lens or a combination of lenses for inspecting objects too small to be seen or too small to be seen distinctly and in detail by the unaided eye. 2. (cap.) Astron. the… …
18radar — /ray dahr/, n. 1. Electronics. a device for determining the presence and location of an object by measuring the time for the echo of a radio wave to return from it and the direction from which it returns. 2. a means or sense of awareness or… …
19Holography — (from the Greek, ὅλος hólos whole + γραφή grafē writing, drawing) is a technique that allows the light scattered from an object to be recorded and later reconstructed so that it appears as if the object is in the same position relative to the… …
20Guide number — The guide number for an electronic flash measures its ability to illuminate the subject to be photographed at a specific film or sensor speed and angle of view. A higher guide number indicates a more powerful flash.For example, doubling the guide …
