Abstract:
A screen for an electron discharge device wherein a target formed of a plurality of fiber optic light pipes is made of a composition including a photochromic material and is selectively subjected to ultraviolet or similar radiation so as to prevent passage of visible light through certain light pipes.
Abstract:
THE TARGER OF A TELEVISION CAMERA TUBE INCLUDES A PHOTOEMITTER OR A PHOTOCONDUCTOR AND A PHOTOCHROMIC GLASS LAYER DISPOSED BETWEEN AN IMAGE BEING VIEWED AND THE SOURCE OF A SCANNING LASER BEAM. THE IMAGE IS FOCUSED ONTO ONE SURFACE OF THE PHOTOCHROMIC GLASS LAYER WHILE THE SCANNING BEAM IS MADE INCIDENT ON THE OPPOSITE SURFACE THEREOF. THE MEAM TRANSMITTED THROUGH THE LAYER EMERGES WITH MODULATED INTENSITY CORRESPONDING TO THE INTENSITY PATTERN OF THE IMAGE AND THEN IMPINGES ON THE PHOTOEMITTER, OFR EXAMPLE, TO GENERATE FREE ELECTRONS MODULATED IN SCAN TIME IN ACCORDANCE WITH THE IMAGE INTENSITY PATTERN. THESE ELECTRONS ARE COLLECTED TO PRODUCE AN ELECTRICAL SIGNAL REPRESENATATIVE OF THE IMAGE.