A Method to Prevent Image Orthicon Burn-In

A device will be described which reduces ``burn-in´´ on an image orthicon tube by as much as 90 per cent. The device is relatively simple and consists of a mechanism to oscillate slowly the lens board of a television camera at a very slow rate. Electrical cancellation of the resulting horizontal motion is accomplished by simple modification to the horizontal centering circuit of the camera. This device should allow a television station to get much longer life out of certain I. O. tubes and, just as important, to eliminate objectionable burn-in to the television viewer.