Color balance adjusting device of photographic negative plate and photographic printing control device applying said device

Abstract

Abstract PURPOSE: To enable the color balance and lightness of television images to be easily adjusted by using an adjusting light source which permits adjustment of the color balance of the luminance of light. CONSTITUTION: Three light source electric bulbs 13 are disposed to a light source part 11 and separation-addition filters 17W19 are disposed thereto; in addition, dimming devices 10 and potentiometers 14 are mounted respectively thereto. If with this constitution the regulating potentiometer 14a is moved, the emitter potential of a UJT transistor rises via a PNP transistor, causing the UJT TR to conduct, then a gate pulse is applied to a TRIAC which controls the supply of AC power source applied to the light source bulbs 13. This causes the period of the power supply to change and finally the luminances of the light source bulbs change. Hence, according to this luminance, the luminances of blue, green and red change. Thereby, the images adequate for an image receiver may be obtained by adjusting the light sources. COPYRIGHT: (C)1981,JPO&Japio

Inventors

• 👤 Motoji Hosozumi

Bibliographic Details