Title:
AUTOMATIC IMAGE CONTRAST CONTROLLER
Document Type and Number:
Japanese Patent JPS596681
Kind Code:
A
Abstract:
The contrast of an image reproduced by a television receiver is manually adjustable by means of a picture control potentiometer, and automatically adjustable by means of an ambient light responsive circuit. Automatic picture control is accomplished selectively, independent of the manual control setting, in accordance with a predetermined combination of ambient light and image brightness levels such that the contrast of bright images, rather than the contrast of all images, is automatically reduced in low ambient light. In a preferred embodiment such automatic picture control is accomplished by using the light responsive circuit to control the threshold operating level of an automatic kinescope beam current limiter of the receiver.
Inventors:
JIYATSUKU SERIGU FUAARA
Application Number:
JP11258783A
Publication Date:
January 13, 1984
Filing Date:
June 22, 1983
Export Citation:
Assignee:
RCA CORP
International Classes:
H04N5/58; (IPC1-7): H04N5/58
Domestic Patent References:
| JPS56116779U | 1981-09-07 | |||
| JPS53137728U | 1978-10-31 | |||
| JPS49123921U | 1974-10-23 |
Attorney, Agent or Firm:
Satoshi Shimizu (2 outside)
Next Patent: ELECTRONIC PHOTOGRAPHING DEVICE