System and Method for Multi TOF Camera Operation Using Phase Hopping

• US 20120098964A1
• Filed: 10/24/2011
• Published: 04/26/2012
• Est. Priority Date: 10/22/2010
• Status: Active Grant

• Current Assignee: Ams Sensors Singapore Pte. Ltd. (Ams-Osram AG)
• Original Assignee: MESA IMAGING AG (Ams-Osram AG)
• Inventors: Oggier, Thierry, Buettgen, Bernhard, Schweizer, Matthias
• Granted Patent: US 9,857,469 B2
• Time in Patent Office: Days
• US Class Current: 348/140
• CPC Class Codes: G01S 17/10 using transmission of interrupted, pulse-modulated waves determination of distance by phase measurements G01S17/32
• CPC Class Codes: G01S 17/36 with phase comparison between the received signal and the contemporaneously transmitted signal
• CPC Class Codes: G01S 17/87 Combinations of systems using electromagnetic waves other than radio waves
• CPC Class Codes: G01S 17/894 3D imaging with simultaneous measurement of time-of-flight at a 2D array of receiver pixels, e.g. time-of-flight cameras or flash lidar
• CPC Class Codes: H04N 13/204 using stereoscopic image cameras stereoscopic photography G03B35/00

Abstract

A modulation technique for 3D time-of-flight (TOF) cameras allows the operation of fully autonomous operated 3D TOF cameras. The method subdivides the exposure time into several sub-exposure intervals, for which the signal control unit adds a preferably pseudo-random common phase delay to the illumination and the sensor.

Claims

1. A time of flight imaging system comprising:

multiple time of flight cameras imaging a scene in which different phase delays are applied in subexposures by each of the cameras.

2. A time of flight imaging method comprising applying the same phase delay to a sensor and an illumination unit of a camera that is changed between subexposures.