Detection of raindrops on a pane by means of a camera and lighting

摘要

A device and a method for detecting rain on a pane, e.g. of a motor vehicle, use a camera or other light sensor and a lighting source. The camera is disposed behind an inner surface of the pane and focused onto a far range that lies in front of an outer surface of the pane. The lighting source generates a source light beam and directs it onto the inner surface of the pane such that at least one resultant reflected beam (r2; r2′) that is reflected from the outer surface of the pane impinges on the camera. The light quantity of the at least one resultant reflected beam is measured by the camera.

主权项

1. A device for detecting rain (4) on an outer surface of a pane, comprising
a camera disposed behind an inner surface of the pane (2), wherein the camera (1) is focused onto a far range that lies in front of the outer surface of the pane (2), and a lighting source (3) adapted to generate a source light beam and configured and arranged to direct the source light beam (h; n) through air onto the inner surface of the pane (2) so as to cause a resultant transmitted beam that is transmitted in the pane and impinges on the outer surface within the pane and is partially reflected from the outer surface (2.2) within the pane (2) to cause a partially reflected beam (r2; r2′) that impinges on the camera (1); and wherein the camera is configured and adapted to measure a light quantity of the partially reflected beam (r2; r2′) impinging on the camera.