Device and method for spatially resolved photodetection and demodulation of modulated electromagnetic waves

US7060957B2 · kind B2 · utility

Assignee

• CSEM Centre Suisse d'Electronique de Microtechnique SA · FR

Inventors

• Robert Lange · Netphen, DE
• Peter Seitz · Munich, DE

Key dates

• Filing date: Mar 26, 2001
• Grant date: Jun 13, 2006
• Expiry date: Jan 4, 2022

Classification

• Technology area (CPC G): Physics
• CPC primary: G01S17/894
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A device and method for spatially resolved photodetection and demodulation of temporally modulated electromagnetic waves makes it possible to measure phase, amplitude and offset of a temporally modulated, spatially coded radiation field. A micro-optical element (41) spatially averages a portion (30) of the scene and equally distributes the averaged intensity on two photo sites (51.1.51.2) close to each other. Adjacent to each of these photo sites (51.1) are two storage areas (54.1, 54.2) into which charge from the photo site can be moved quickly (with a speed of several MHz to several tens or even hundreds of MHz) and accumulated essentially free of noise. This is possible by employing the charge-coupled device (CCD) principle. The device combines a high optical fill factor, insensitivity to offset errors, high sensitivity even with little light, simultaneous data acquisition, small pixel size, and maximum efficiency in use of available signal photons for sinusoidal as well as pulsed radiation signals. The device and method may be used in a time-of-flight (TOF) range imaging system without moving parts, offering 2D or 3D range data.