Laser hydrography

US8307705B2 · kind B2 · utility

Assignee

• RIEGL LASER MEASUREMENT SYSTEMS GMBH · AT

Inventors

• Andreas Ullrich · Eßlingen, DE
• Martin Pfennigbauer · Tulln, AT

Key dates

• Filing date: Jun 16, 2010
• Grant date: Nov 13, 2012
• Expiry date: Mar 5, 2031

Classification

• Technology area (CPC G): Physics
• CPC primary: G01C13/008
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

Method for laser hydrography in which at least one laser beam is emitted from a known location and in a known direction onto the surface of a body of water and through the water onto the bottom of the body of water and measurement points of the water surface and the water bottom in a coordinate system are determined from transit-time measurements of the reflections of the laser beam at the water surface and water bottom, wherein the local inclination of the water surface at an entry point of the laser beam into the body of water is determined from at least three measurement points of the water surface, wherein a local entry angle of the laser beam into the body of water is determined from the local inclination and the known direction of the laser beam, and wherein the measurement point of the water bottom is created as a function of the laser beam direction, the local inclination, and the optical refraction due to the corresponding local entry angle of the laser beam.