Definitions for scotophor
sco·tophor

WikipediaRate this definition:0.0 / 0 votes

1. Scotophor

   A scotophor is a material showing reversible darkening and bleaching when subjected to certain types of radiation. The name means dark bearer, in contrast to phosphor, which means light bearer. Scotophors show tenebrescence (reversible photochromism) and darken when subjected to an intense radiation such as sunlight. Minerals showing such behavior include hackmanite sodalite, spodumene and tugtupite. Some pure alkali halides also show such behavior. Scotophors can be sensitive to light, particle radiation (e.g. electron beam – see cathodochromism), X-rays, or other stimuli. The induced absorption bands in the material, caused by F-centers created by electron bombardment, can be returned to their non-absorbing state, usually by light and/or heating. Scotophors sensitive to electron beam radiation can be used instead of phosphors in cathode ray tubes, for creating a light absorbing instead of light emitting image. Such displays are viewable in bright light and the image is persistent, until erased. The image would be retained until erased by flooding the scotophor with a high-intensity infrared light or by electro-thermal heating. Using conventional deflection and raster formation circuity, a bi-level image could be created on the membrane and retained even when power was removed from the CRT. In Germany, scotophor tubes were developed by Telefunken as blauschrift-röhre ("dark-trace tube"). The heating mechanism was a layer of mica with transparent thin film of tungsten. When the image was to be erased, current was applied to the tungsten layer; even very dark images could be erased in 5–10 seconds.Scotophors typically require a higher-intensity electron beam to change color than phosphors need to emit light. Screens with layers of a scotophor and a phosphor are therefore possible, where the phosphor, flooded with a dedicated wide-beam low-intensity electron gun, produces backlight for the scotophor, and optionally highlights selected areas of the screen if bombarded with electrons with higher energy but still insufficient to penetrate the phosphor and change the scotophor state.The main application of scotophors was in plan position indicators, specialized military radar displays. The achievable brightness allowed projecting the image to a larger surface. The ability to quickly record a persistent trace found its use in some oscilloscopes.

How to pronounce scotophor?

1. Alex

   US English

   David

   US English

   Mark

   US English

   Daniel

   British

   Libby

   British

   Mia

   British

   Karen

   Australian

   Hayley

   Australian

   Natasha

   Australian

   Veena

   Indian

   Priya

   Indian

   Neerja

   Indian

   Zira

   US English

   Oliver

   British

   Wendy

   British

   Fred

   US English

   Tessa

   South African

How to say scotophor in sign language?

Numerology

1. Chaldean Numerology

   The numerical value of scotophor in Chaldean Numerology is: 1

2. Pythagorean Numerology

   The numerical value of scotophor in Pythagorean Numerology is: 3

References

1. ^ Wikipedia
   https://en.wikipedia.org/wiki/Scotophor