Patent · US Expired

Rain sensor with improved avoidance of reflected light

US4987296A · kind A · utility

27Cited by
2References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 10, 1989
Grant dateJan 22, 1991
Priority date
Expiry dateAug 10, 2009

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01V8/10
  • WIPO fieldTransport
  • WIPO sectorMechanical engineering

Abstract

A rain sensor operates such that when a raindrop cuts off a direct light beam from a transmitter to a detector, the output level of the detector is lowered. A convex member is disposed to prevent a portion of the light emitted from the transmitter from reflecting and then reaching the detector. Thus, detecting error due to such reflected light is reduced.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.