Exposure interlock for oscilloscope cameras

An exposure interlock has been developed for oscilloscope cameras which cuts off ambient light from the oscilloscope screen before the shutter of the camera is tripped. The invention described herein was made by employees of the United States Government and may be manufactured and used by or for the Government for governmental purposes without the payment of any royalties thereon or therefor. It is also known in the art that means can be employed to provide accurate timing of one movement with respect to another particularly with relation to operation of the shutter.