| 摘要 |
<p>In order to avoid the driver of a vehicle having to remember to switch on the lighting system of an automobile the present invention proposes means responsive to a change in light level to activate the lighting system below a predetermined ambient light level. The means comprises a photoelectric cell (18) and a processor (IC1) which monitors a signal with respect to a level set by resistor (VR1) and activates the lights if that level persists for a period set by resistor (VR2). A feedback loop (29) avoids deactivation.</p> |
