| 摘要 |
<p>1,235,012. Image pick-up tubes. INTERNATIONAL BUSINESS MACHINES CORP. 7 Nov., 1969 [14 Nov., 1968], No. 54613/69. Heading H1D. A vidicon tube is illuminated with a high intensity burst of light lasting less than 10 microseconds to remove any stored charge before a fresh image is optically projected on to the target, and a second image is written over the optical image by scanning the target with a modulated electron beam. The additional input provided by scanning with a modulated electron beam may occur before or simultaneously with the optical input, and a subsequent scanning with an unmodulated beam develops the video output signal corresponding to the combined inputs. The beam voltage and/or current - should be higher for the writing scan than for the reading scan. In another mode of operation, after the flash the target is negatively charged by scanning with an unmodulated beam either before or simultaneously with the optical input; this is followed by scanning with a modulated beam to supply the second input, and by scanning with an unmodulated beam to derive the video output signal.</p> |
