Graphecon

a cathode-ray memory tube with two electron beams. The first beam records a long-duration television-generated or radar-generated image as a charge pattern on a thin layer of a dielectric deposited on an electrically conductive plate. The second electron beam provides a multiple readout from this plate.

In a graphecon. recording and readout can be performed simultaneously and independently. The number of readout cycles from an image obtained in a single recording operation can be as high as several thousand; the resolution of a graphecon is 1,200 lines. Graphecons are used in the mutual conversion of images—for example, of a radar image into a television image or of an image conforming to one television standard into an image conforming to a different television standard.