| 摘要 |
PURPOSE:To see a picture with good visibility day and night through simple constitution by controlling luminance, contrast, and color saturation of an on- vehicle color cathode ray tube associatively with the lighting switch of the vehicle. CONSTITUTION:While outdoor light is bright in the daytime and the lighting switch 1 of the vehicle is off, an interlocking switch 3 is also off and a transistor (TR)4 is off, so that no current is conducted through a relay coil 500 to open contacts 510, 520, and 530. When the outdoor light is scarece at night and the lighting switch is closed, the interlocking switch 3 is closed to conduct a current through the relay coil 500. Consequently, relay contacts 510, 520, and 530 are closed and the 2nd video amplifying circuit and color band amplifying circuit (not shown in a figure) vary resistance value to adjust to the optimum luminance and color saturation. |
