| 摘要 |
PURPOSE:To improve the capability of diagnosing by expanding the effective lighting field of a television camera over the whole output surface, by using as a control signal the signal which has the halation part, appearing in a video signal, force to drop in level. CONSTITUTION:When video signal IN having a part of high brightness causing halation at both ends is inputted, signal V1 having a high level at parts except blanking signal part BL containing synchronizing pulses appears at the output terminal of comparator 8, and signal V2 held at the high level only in the period that corresponds to the halation part appears at the output terminal of comparator 9. Mixer 13 mixes inverted signal V4 of signals V1 and V2, and signal IN together and transmission gate FETQ1, on the other hand, outputs signal V5 which shows only the effective information part. Signal V5 is inputted to an automatic brightness regulating circuit. Therefore, video signal Out inputted to an amplifying circuit is that having the halation part of signal IN included in the blanking area. |
