for viewing through a very small aperture

john9221 · Wysłany: Pon 20:52, 21 Mar 2011

yilai:
[link widoczny dla zalogowanych]
[link widoczny dla zalogowanych]

[link widoczny dla zalogowanych]

ectrons from a metal whose surface is exposed to light. Photon. A representative of the quantum nature of light. It is considered as the smallest unit of light.PHOTOPIC VISIONThe range of light intensities [link widoczny dla zalogowanych], from 105 lux down to nearly 10-2 lux, detectable by the human eye.PINHOLE LENSA fixed focal length lens [link widoczny dla zalogowanych], for viewing through a very small aperture, used in discrete surveillance situations. The lens normally has no focusing control but offers a choice of iris functions.PIXELDerived from picture element. Usually refers to the CCD chip unit picture cell. It consists of a photo sensor plus its associated control gates.PLUMBICONThermionic vacuum tube developed by Philips, using a lead oxide photoconductive layer. It represented the ultimate imaging device up to the introduction of CCD chips.POLARISING FILTERAn optical filter that transmits light in only one direction (perpendicular to the light path) [link widoczny dla zalogowanych], out of 360° possible. The effect is such that it can eliminate some unwanted bright areas or reflections, such as when looking through a glass window. In photography, polarising filters are used very often to darken a blue sky.POTSPlain Old Telephone Service, ie. the telephone service in common use throughout the world today. Also known as PSTN.PRESET P