摘要 |
A safety shut-off protection system is provided for a light responsive system such as video cameras, image intensifiers, thermal imagers, or the like. The light responsive system further includes several series-connected, normally-closed, light responsive photoelectric Darlington safety switches. These safety switches are located to receive light along with the light responsive systems. Light exceeding a threshold intensity impinging on any one of the Darlington safety switches causes such a switch to operate to deactivate the light sensitive system.
|