| 摘要 |
1,187,848. Colour television. THOMSON C.S.F. 21 July, 1967 [29 July, 1966], No. 33724/67. Heading H4F. To reduce distortion due to lack of symmetry in the three primary colour signal channels in a colour television camera, the component colour signals are subjected to time division multiplexing at a frequency above the highest frequency in the bandwidth of the component colour signals, the resultant signals are fed to a common signal correction circuit (e.g. for gamma correction, for varying the amplitude of the signals, and for establishing the black level) and the corrected output from the correction circuit is fed to a decoder operating in synchronism with the time division multiplexing to deliver reconstructed corrected component colour signals. The time division and decoding is effected by electronic switches, one for each component colour signal, which are controlled by sequences (one for each switch) of sampling pulses of the same repetition frequency but time shifted i.e. delayed, with respect to each other. Correction of the luminance signal may also be effected. |
