Deflector control circuit

Abstract

A medical diagnostic system and method is disclosed for producing television and laser light images of penetrative radiation patterns from a subject as converted to visible light images by an image tube. The apparatus includes a penetrative radiation source for directing radiation through a subject, an image tube for receiving that radiation and in response producing a visible nonlaser light image corresponding to the pattern of such radiation impinging upon the image tube. The apparatus also includes a television camera for viewing the image tube output. A laser beam recorder receives a composite television signal from the television camera and in response produces a laser light image corresponding to the image viewed by the television camera. The laser beam recorder produces a laser beam. The recorder includes apparatus for deflecting the beam horizontally and vertically with a mechanical scanner, in accordance with the synchronization signals of the television composite to produce an image raster with the laser light. The laser beam recorder also amplitude modulates the beam with the analog video portion of the television signal to produce a laser image. A novel control circuit controls the operation of the mechanical scanner, over an excursion, while inhibiting undesirable harmonic oscillation at the end of the excursion.