The printicon: A new character-generating monoscope for use in visual display systems

A brief review of existing means of generating charactors for visual display reveals certain deficiencies. A new character-generating monoscope has been developed to overcome these problems. Its novel all-electrostatic electron-optical system produces, at high speed, well-defined images of the target symbols which can be designed to customer requirements. The tube is cheap, and its low voltage and power requirements enable significant cost savings to be made in the associated circuits. Its small dimensions, 30-mm diameter by 175-mm long, facilitate its use in small desk-mounted display units. The stencil target imposes no limitation on the usage nor on the operational life of the monoscope. The tube uses a new electron gun with low cathode loading. Four tubes have been life-tested to date and have so far achieved more than 3000 operational hours with negligible loss in performance. Lifetimes exceeding 5000 hours are expected. The tube has been used in computer visual display terminals and for labeling radar screens.