Photographic recording device for video image

摘要

A photographic recording device such as may be used for recording images displayed on a cathode-ray tube screen on photographic film in which lenses of different focal length can alternatively be disposed in an optical path between the cathode-ray tube screen and the film. First and second lenses are mounted at ends of respective first and second lens arms. The lens arms are attached to a rotatable shaft with a vertical clearance and a predetermined angle therebetween. Rotary power from a motor is conveyed to the rotary drive shaft via a crank mechanism to cause a reciprocal swinging movement of the two lens arms. A snap spring biases the lens arms in either direction selectively. First and second stops determine the extent of the swinging movement to stably hold the lens arms so as to position the optical axes of the respective first and second lenses in alignment with the optical path of the recording device.