Time-of-flight camera with location sensor system

Patent metadata

Field	Value
Publication number	US-9922427-B2
Application number	US-201414297999-A
Country	US
Kind code	B2
Filing date	Jun 6, 2014
Priority date	Jun 6, 2014
Publication date	Mar 20, 2018
Grant date	Mar 20, 2018

Abstract

A time-of-flight (TOF) camera system includes a radiation source, a radiation detector, a location sensor system and a processor. The radiation source is configured to generate and emit a radiation that strikes a target object. The radiation detector is configured to detect the radiation reflected from the target object and generate a sample set comprising at least two raw samples detected in succession at different times based on the reflected radiation. The location sensor system is configured to detect movements of the TOF camera during the detection and generate a movement signal having portions thereof uniquely corresponding to each of the raw samples of the sample set based on the movements of the TOF camera, wherein a portion of the movement signal is detected at a same time of generating the corresponding raw sample. The processor is configured to receive the raw samples and the corresponding movement signal portions and generate an object information based on the raw samples and the corresponding movement signal portion.

First claim

What is claimed is:

1. A time-of-flight (TOF) camera system, comprising:
a radiation source configured to generate and emit a radiation that strikes a target object;
a radiation detector configured to detect the radiation reflected from the target object and generate a sample set comprising raw samples detected at corresponding sampling times, the raw samples including a first raw sample and a second raw sample detected in succession during a first sampling time and a second sampling time, respectively, based on the reflected radiation;
a location sensor system configured to detect movements of the TOF camera system without using the raw samples of the sample set during the detection and generate a movement signal having portions corresponding to sampling times of the raw samples of the sample set based on the movements of the TOF camera system, wherein a first portion and a second portion of the movement signal corresponds to the first sampling time and the second sampling time, respectively; and
a processor configured to receive the raw samples and the corresponding movement signal portions and generate three dimensional (3D) image information for the target object based on processing of the raw samples with the corresponding movement signal portions;
wherein the processor is configured to keep the first raw sample and selectively discard the second raw sample of the sample set; wherein selectively discarding of the second raw sample is based on whether the second portion of the movement signal exceeds a pre-determined threshold movement value, and selectively discarding of the second raw sample is independent of the raw samples of the sample set.

2. The TOF camera system of claim 1 , wherein the 3D image information comprises a distance information between the TOF camera system and the target object or a reflection intensity information of the target object.

3. The TOF camera system of claim 1 , wherein the location sensor system comprises an accelerometer, gyroscope, inclinometer, magnetometer, electronic compass, Global Position System (GPS) or combinations thereof.

4. The TOF camera system of claim 1 , wherein the radiation detector further comprises a pixel array configured to detect the radiation reflected from different portions of the target object, a pixel of the pixel array generating a corresponding sample set comprising raw samples detected in succession at different times, wherein the corresponding sample set are processed together with the portions of the movement signal corresponding to each raw sample of the sample set to generate the 3D image information of a corresponding portion of the target object.

5. The TOF camera system of claim 1 , wherein the processor comprises a reference signal synchronized with the emitted radiation from the radiation source.

6. The TOF camera system of claim 4 , wherein the processor further processes the object information of the different portions of the target object and generate the 3D image of the target object.

7. The TOF camera system of claim 1 , wherein the radiation is a visible spectrum, ultraviolet, infrared, x-ray, terahertz, microwave or radio radiation.

8. The TOF camera system of claim 1 , wherein the radiation detector comprises a Photon Mixing Device (PMD).

9. A time-of-flight (TOF) camera system, comprising:
a radiation source configured to generate and emit a radiation that strikes a target object;
a radiation detector comprising a pixel array configured to detect the radiation reflected from corresponding portions of the target object, the pixel array detecting a frame set with a plurality of raw frames detected in succession at different sampling times, wherein one portion of the target object corresponds to one sample set with a plurality of raw samples which are spread over the plurality of raw frames;
a location sensor system configured to detect movements of the TOF camera system without using the raw samples of the sample set during the radiation detection and generate a corresponding movement signal comprising portions corresponding to each of the raw samples of the sample set, wherein a first portion and a second portion of the movement signal are generated at a first sampling time and a second sampling time, respectively, and a first raw sample and a second raw sample are generated at the first sampling time and the second sampling time, respectively; and
a processor configured to receive the sample set and select at least two raw samples from the sample set based on the corresponding portions of the movement signal, and further configured to generate an object information for the corresponding portion of the target object based on the selected raw samples, the processor further configured to process the object information for the various portions of the target object and generate a three-dimensional image of the target object based on processing of the selected raw samples with the corresponding portions of the movement signal;
wherein the processor is further configured to discard some raw samples of a raw frame corresponding to some portions of the target object while keeping some other raw samples of the raw frame corresponding to some other portions of the target object if a corresponding portion of the movement signal exceeds a pre-determined threshold movement value; wherein the kept raw samples overlap with some raw samples of another raw frame detected previously corresponding to the same portions of the target object.

10. The TOF camera system of claim 9 , wherein the raw samples correspond to distance information regarding the target object, and wherein the distance information is generated based on a phase shift of the reflected radiation to the emitted radiation, the phase shift acquired from comparing at least four raw samples detected at different sampling times and selected from the sample set with a reference signal having at least four different pre-set delays with respect to the emitted radiation.

11. The TOF camera system of claim 9 , wherein the raw samples are selected from the sample set such that the corresponding portions of the movement signal are within a pre-determined threshold.

12. The TOF camera system of claim 9 , wherein the movement signal comprises a location or rotation information of the TOF camera system.

13. The TOF camera system of claim 1 , wherein whether to discard a raw sample is determined based on the corresponding portion of the movement signal prior to processing remaining raw samples of the sample set.

14. A time-of-flight (TOF) camera system for determining three dimensional (3D) image information regarding a target object, the TOF camera system comprising:
a pixel array comprising a first pixel and a second pixel which are arranged at different locations within the pixel array, the first pixel configured to detect a first raw sample corresponding to a first portion of the target object at a first sampling time, and the second pixel configured to detect a second raw sample corresponding to the first portion of the target object at a second sampling time, the second sampling time differing from the first sampling time;
a location sensor system configured to generate a movement signal which tracks movement of the TOF camera system in time without use of the pixel array, the movement signal comprising a first movement signal portion corresponding to the first sampling time and a second movement signal portion corresponding to the second sampling time; and
a processor configured to determine the 3D image information for the target object based on the first raw sample and selectively based on the second raw sample, wher

Assignees

• Infineon Technologies Ag

Inventors

• Dielacher Markus
• Prainsack Josef
• Flatscher Martin
• Mark Michael

Classifications

• G01C11/08

  the pictures not being supported in the same relative position as when they were taken · CPC title

• G01S17/894

  Three-dimensional [3D] imaging with simultaneous measurement of time-of-flight at a two-dimensional [2D] array of receiver pixels, e.g. time-of-flight cameras or flash lidar · CPC title

• G01S17/86

  Combinations of lidar systems with systems other than lidar, radar or sonar, e.g. with direction finders · CPC title

• H04N7/183

  for receiving images from a single remote source · CPC title

• G01S7/497

  Means for monitoring or calibrating · CPC title