| 摘要 |
1511262 Scanning standard conversion SOC ANON DE TELECOMMUNICATIONS 23 April 1975 [7 May 1974] 16727/75 Heading H4F A single-line scanning camera, which is carried by an aircraft so that it is moved relative to the scanned scene to provide the second component of scan, feeds a double gun storage tube which is read out repeatedly to provide a video signal for a conventional television display. The target of the tube is scanned by the writing gun at a frame rate which depends on the speed and altitude of the aircraft. The stored lines are successively erased so as to provide a moving charge-free rectangular area on the target. The charged area is read out by the reading gun such that, during a read frame, the first and last lines read are on opposite sides of the charge-free area. Erasure may be performed by the writing gun or the reading gun. |
