Distance sensor and method for detecting a distance

US7186965B2 · kind B2 · utility

Assignee

• Fraunhofer-Gesellschaft zur förderung der angewandten Forschung e.V. · DE

Inventors

• Olaf Schrey · Ratingen, DE
• Werner Brockherde · Duisburg, DE
• Bedrich Hosticka · Rübhausen, DE

Key dates

• Filing date: Apr 25, 2006
• Grant date: Mar 6, 2007
• Expiry date: Apr 25, 2026

Classification

• Technology area (CPC G): Physics
• CPC primary: G01S17/931
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

An indirect detection of the reflected radiation pulses, when measuring a distance by means of the photoeffect, allows considerably expanding the usability of the distance sensor and the distance measuring method, wherein the adaption to a new field of application only requires little design changes. Since in the external photoeffect the photoelectrons are ejected from the material irradiated photon by photon or quantum by quantum and the photons, when being ejected, only require a certain minimum energy and correspondingly the radiation used for irradiation only requires a sufficiently small wavelength, the external photoeffect allows detecting radiation over a large spectral range. When interferences occur in a certain wavelength range in a certain field of application, the operating wavelength range of the distance sensor technology may at first simply be set to another spectral range by using such an irradiation source having a spectrum outside the spectral range containing the interferences.