| 摘要 |
<p>PROBLEM TO BE SOLVED: To lessen incompatibility feeling in operation by adjusting the quantity of illumination light using a differential signal produced in accordance with the quantity set by a light quantity setting means, at the same time, determining stop of the illumination light and also the max. lighting quantity, and thereby stabilizing the lighting with the max. quantity of the illumination light and the lighting stopping. SOLUTION: The brightness of the illumination light set by a dimmer dial 1 is fed as an illumination control signal 2 to an integration circuit 3 and a differentiating circuit 5, converted into an integral signal 4 and differential signal 6, and outputted to a microcomputer 7 from an A/D port (a) and digital port (b). The microcomputer 7 detects whether a digital converted differential signal 6 is emitted or not, and if yes, its peak is detected from the integral signals 4 to serve for calculation of the set brightness, and thereupon the brightness of a lighting system 9 is adjusted to the obtained brightness through calculation. If no such a signal 6 is emitted, judgement is made, based on the peak of the integral signals 4, whether the illumination light is to be stopped or the brightness of the illumination light is to be set to the maximum.</p> |
