| 摘要 |
<p>An apparatus for operating a windshield wiper having an automatic wiper control. The apparatus is provided with a rain sensor having a light-emitting transmitter and a receiver that responds to the emitted light by emitting a sensor signal, and an evaluation device for the sensor signal. The evaluation device has a microcomputer and a capacitor that is outside of the microcomputer and to which the sensor signal is supplied. Also included is a comparator connected to the capacitor for comparing the voltage built up at the capacitor by the sensor signal to a threshold voltage and for emitting an output signal if the threshold voltage is exceeded. The microcomputer forms a measured value from the output signal, the value of which correspond to a time at which the threshold is exceeded.</p> |
