Image Sensor, Vidicon, SIVIT

This is a silicon target phototube used by James Westphal and his group for astronomical imaging. This vacuum tube, manufactured by RCA, consists of a Vidicon imaging tube, similar to those used for TV, in which the photosensitive front image target has been replaced by a silicon photodiode.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. Called a SIVIT (Silicon Intenified Vidicon Tube), it was quite sensitive and had a wide dynamic range. Cooling to -65C enhanced the signal to noise ratio. It was used extensively in studies of the stars.

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