Title:
【発明の名称】ガンマ補正回路
Document Type and Number:
Japanese Patent JPH069376
Kind Code:
B2
Abstract:
PURPOSE:To prevent deterioration of picture quality by generating a gamma control signal to an APL signal level and the sensitivity of a video camera so as to improve the S/N when the sensitivity of the video camera is switched. CONSTITUTION:A luminance signal of R, G, B signals being outputs of a television camera is fed to input terminals 1R, 1G, 1B and an APL signal is impressed to a base of a transistor Q1 being a component of a gamma correction control signal generating circuit via an operational amplifier. On the other hand, the tri- state sensitivity is selected by a sensitivity changeover switch 3 by using a sensitivity switching control signal fed to an input terminal 4 and the sensitivity state and the APL signal generates a gamma correction control signal. The control signal is fed to gamma correction circuits 6R, 6G and 6B, where the gamma correction in response to each luminance signal is applied and an output is obtained from output terminals 7R, 7G and 7B.
Inventors:
TAKAHASHI ISAO
Application Number:
JP7631684A
Publication Date:
February 02, 1994
Filing Date:
April 16, 1984
Export Citation:
Assignee:
VICTOR COMPANY OF JAPAN
International Classes:
H04N5/202; H04N9/04; H04N9/69; (IPC1-7): H04N5/202; H04N9/04; H04N9/69
Domestic Patent References:
| JP53124017A | ||||
| JP4977523A |
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