| 摘要 |
PURPOSE:To facilitate adjusting of the referential level of rear light sensor without sacrifice of the function for maintaining anti-glare condition when the quantity of light from the rear will vary drastically by providing means for adjusting the referential level. CONSTITUTION:Upon turning on of key switch S1, power is fed to the drive circuit 130 for an anti-glare reflection mirror to apply A.C. voltage onto a liquid crystal panel 100. The referential voltage V+ of decision circuit 8 in driving circuit 130 can be adjusted through referential voltage adjusting circuit to desired level while the switches S2, S3 will rise/lower the referential voltage respectively in pulse. In order to operate the switches S2, S3 thus to adjust the detection sensibility of rear light, switch S2 is turned on to rise the referential voltage V+. Said signal is fed to the input terminal of OR gate 60 in anti- glare condition releasing circuit 6 and the variation of detection sensibility of rear light will appear quickly as the variation of anti-glare condition of room mirror. |
