Vidicon having external light source adjacent sealed end, and light conductor transmitting light therefrom to target

Claim 1

A television camera comprising an evacuated envelope having an exhaust tube with a substantially triangular sealed tip and a transparent wall portion opposite said exhaust tube, a photoconductive target having one surface facing said transparent wall portion for receiving an image of a scene, means to scan the opposite side of said screen with an electron beam thereby generating an electrical current corresponding to light variations in said scene, said scan means including an electron gun for generating an electron beam remote from the screen and means to deflect the electron beam before it impinges on the screen, and means for uniformly illuminating the target comprising an electrode between said electron gun and target, said electrode having a section of reduced size nearer said gun and a section of greater size nearer said target, said sections being connected by a frustoconical section, a rod-shaped lightconductor terminating in the sealed tip of the exhaust tube and extending therefrom through an aperture in said frustoconical section, a light source external to said envelope and adjacent said sealed tip, and means for directing light from said source through said tip to said light-conductor, whereby light from said source is transmitted to said target.