Image Sensor, Vidicon, SIDAC

This is the first of a series of experimental silicon target phototubes used by James Westphal and his group for astronomical imaging. This vacuum tube was initially developed and manufactured at the Bell Laboratories for use with telephone picture phones. It consists of a Vidicon imaging tube, similar to those used for TV, in which the photosensitive front image target has been replaced by a silicon photodiode. The back of the target is scanned by beam of electrons; these create a current when they meet an area of the target that has been exposed to light. This current is then converted electronically into an image. The SIDAC, which was quite sensitive and had a wide dynamic range, was used to study the planets.

The California Institute of Technology donated this to the Museum in 1983.