Windshield wiper system with rain detector
First Claim
1. A windshield wiper system for a vehicle, comprising a windshield transparency detector which include a plurality of sources of frequency modulated light and a plurality of sensors for said light, said sources and sensors being arranged in a two dimensional array on a common zone of the windshield, each source radiating nondirectional light to propagate in said windshield to impinge upon each of said sensors, the system further comprising a demodulation circuit associated with each said light sensor for demodulating each of the frequencies of the light from said sources and for providing a signal corresponding to each demodulation.
1 Assignment
0 Petitions
Accused Products
Abstract
In a windshield wiper system for vehicles, with which a rain detector is associated, the rain detector operates according to the principle of detection of the absorption by wet glass of light rays which are subjected to multiple total reflections within the windshield.
The detector comprises a plurality of non-directional light sources together with a plurality of sensors each of which receives the light from the various sources. The light sources are modulated at different frequencies, and the sensors are associated with demodulation circuits, such that more detailed and accurate information as to the nature of the reductions in transparency of the windshield is obtained. The windshield wiper system is then activated in the light of this detailed information.
-
Citations
6 Claims
- 1. A windshield wiper system for a vehicle, comprising a windshield transparency detector which include a plurality of sources of frequency modulated light and a plurality of sensors for said light, said sources and sensors being arranged in a two dimensional array on a common zone of the windshield, each source radiating nondirectional light to propagate in said windshield to impinge upon each of said sensors, the system further comprising a demodulation circuit associated with each said light sensor for demodulating each of the frequencies of the light from said sources and for providing a signal corresponding to each demodulation.
Specification