Rain sensor with reference channel
US4960996A · kind A · utility
Inventor
Key dates
| Filing date | Jan 18, 1989 |
| Grant date | Oct 2, 1990 |
| Priority date | — |
| Expiry date | Jan 18, 2009 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S318/02
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A sensing assembly (10) for indicating when moisture or other particles have accumulated on a window (12) having inside (14) and outside (16) surfaces. The assembly includes an emitter (18) disposed on the inside surface (14) of the window (12) to emit infrared energy to the window (12). A detector (20) is disposed on the inside surface (14) to detect infrared energy from the window (12) on an egress axis. A reference detector (22) detects ambient light and emitter output which are parallel to the egress axis. A control circuit (24) receives the detected measurement level and reference level for comparison to actuate the wipers when rain or particles are on the window (12).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.