A developmental tricolor vidicon having a multiple-electrode target

Abstract

Color television cameras which are now widely used require three separate camera tubes to supply the simultaneous primary color information transmitted by the compatible system. This paper describes a developmental tricolor camera tube of the vidicon type for use in a single-tube color camera. The ability to generate the three simultaneous signals is achieved in the tricolor vidicon by means of a multiple-electrode target structure having three interlocking groups of color-sensitive strips connected to separate output terminals for each primary color. A single low-velocity electron beam scans the photoconductive target. No special requirements are made on the beam with respect to focus or scanning accuracy. Registry of the three signals is inherent in the design of the target. The performance of the developmental cameras which have been constructed to date does not equal the three-tube image orthicon camera from the standpoint of sensitivity, color fidelity, and uniformity. In its present state, the tube is potentially useful for industrial and scientific purposes where sufficient light is available and structural defects do not obscure the information desired. To extend its range of application, the development of more sensitive photoconductors and improved methods of fabrication are required.