CRT LIGHT-HEAD FOR AN AUTOMATIC DRAFTING SYSTEM

Abstract

This thesis describes the method of implementation of a cathode-ray tube (CRT) for use with a high quality precision automatic drafting system intended for the preparation of maps on a flatbed drafting table. A CRT light-head, mounted in place of the normal optical-mechanical light-head on a drafting table, enables the production of a wide range of symbolized line features as well as symbols and names. The image on the CRT, which is generated according to the information received from a library file in the computer, is projected via an optical system onto a photo-sensitive material. This system also permits the application of 'area-fill° by means of the CRT light-head to save the use of 'peel-coat.' The system utilizes a PDP8/e mini-computer with 8K words of core memory, an 1.6M word disc unit, a 9-track magnetic tape unit, a CRT light-head, and a precision flat- bed drafting table.