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Title: Flash protection controller

A controller provides a high voltage to maintain an electro-optic shutter in a transparent condition until a flash of light which would be harmful to personnel is sensed by a phototransistor. The controller then shorts the shutter to ground to minimize light transmission to the user and maintains light transmission at the pre-flash level for a predetermined time to allow the flash to subside. A log converter and differential trigger circuit keep the controller from being triggered by other light flashes which are not dangerous.
  1. (Mountain View, CA)
Publication Date:
OSTI Identifier:
Report Number(s):
US 4282429
DOE Contract Number:
Resource Type:
Research Org:
Sandia National Laboratories (SNL), Albuquerque, NM, and Livermore, CA
Country of Publication:
United States
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