3D camera

• US 7,560,679 B1
• Filed: 05/02/2006
• Issued: 07/14/2009
• Est. Priority Date: 05/10/2005
• Status: Expired due to Fees

• Current Assignee: Nan Chang O-Film Optoelectronics Technology, Ltd., Printronix
• Original Assignee: SIIMPEL CORPORATION (Adeia Inc.)
• Inventors: Gutierrez, Roman C.
• Primary Examiner(s): Epps; Georgia Y
• Assistant Examiner(s): WILLIAMS, DON J
• Application Number:
  US11/416,882
• Time in Patent Office: 1,169 Days
• Field of Search: 250/208.1, 250/216, 250/226, 250/221, 250/330, 250/336.1, 348/289, 348/290, 348/294, 348270-279, 356/402, 356/404, 356/414, 356/416, 356/419, 356 3- 9, 257/294, 257431-432, 257290-291, 257/440
• US Class Current: 250/208.1
• CPC Class Codes: G01C 3/08 Use of electric radiation detectors
• CPC Class Codes: G01J 3/0278 Control or determination of height or angle information for sensors or receivers
• CPC Class Codes: G01J 3/513 having fixed filter-detector pairs
• CPC Class Codes: G01S 17/34 using transmission of continuous, frequency-modulated waves while heterodyning the received signal, or a signal derived therefrom, with a locally-generated signal related to the contemporaneously transmitted signal
• 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 13/207 using a single 2D image sensor
• CPC Class Codes: H04N 13/254 in combination with electromagnetic radiation sources for illuminating objects
• CPC Class Codes: H04N 13/257 Colour aspects
• CPC Class Codes: H04N 23/84 for processing colour signals
• CPC Class Codes: H04N 25/131 including elements passing infrared wavelengths
• CPC Class Codes: H04N 25/136 using complementary colours
• CPC Class Codes: H04N 9/03 Circuitry for demodulating colour component signals modulated spatially by colour striped filters by frequency separation

Abstract

Structures and methods are provided for obtaining depth information regarding a scene being imaged. The scene is illuminated with light having a time varying parameter. Light reflected from the scene is received and values for the time varying parameter associated with different portions of the scene are determined.

Claims

1. A filter, comprising:

a plurality of pixelated visible light filter elements, each of which transmits a band of visible light;

a plurality of pixelated invisible light filter elements, each of which transmits a band of invisible light; and

,

a plurality of frequency counters, each respectively associated with a respective one of the invisible light filter elements and operable to measure the frequency of intensity modulations of the invisible light respectively transmitted therethrough.

2. The filter as recited in claim 1, wherein the visible light is red, green, and blue light and the invisible light is infrared light.

3. The filter as recited in claim 1, wherein the visible light is cyan, yellow, and magenta light and the invisible light is infrared light.

4. The filter as recited in claim 1, wherein three visible light filter elements and one invisible light filter element define a pixel.

5. An imaging sensor, comprising:

an array of light sensitive elements;

a filter configured to transmit visible light to the array for two dimensional imaging and configured to transmit invisible light to the array for depth imaging; and

,

an array of frequency counters, each respectively associated with a selected one of the invisible light sensitive elements and operable to measure the frequency of intensity modulations of the light respectively transmitted thereto.

6. The imager as recited in claim 5, wherein the light sensitive elements comprise CMOS devices.

7. The imager as recited in claim 5, wherein the filter comprises an IRGB filter.

8. A camera, comprising:

a source of invisible light associated with the camera that changes in frequency during imaging and is arranged to illuminate a scene being imaged by the camera;

an imaging sensor; and

,

a filter configured to selectively transmit visible light to selected pixels of the imaging sensor and configured to transmit invisible light supplied directly thereto from the source combined with invisible light reflected back from the scene to other pixels of the imaging sensor a plurality of frequency counters, each respectively associated with a respective one of the invisible light filter elements and operable to measure the frequency of intensity modulations of the invisible light respectively transmitted there through.

9. The camera as recited in claim 8, wherein the imaging sensor comprises a CMOS imaging sensor.

10. The camera as recited in claim 8, wherein the filter comprises an IRGB filter.

11. The camera as recited in claim 8, wherein the source of invisible light comprises a tunable infrared laser.

12. The camera as recited in claim 8, further comprising a combiner configured to combine the infrared light reflected from the scene with the infrared light supplied directly thereto from the source and to provide the combined light to the imaging sensor.

13. The camera as recited in claim 8, further comprising a frequency counter configured to count a beat frequency of the infrared light reflected from a scene after combination with the infrared light supplied directly thereto from the source.

14. The camera as recited in claim 8, wherein the imaging sensor comprises at least one frequency counter configured to count a beat frequency from selected pixels thereof.

15. The camera as recited in claim 8, wherein the imaging sensor comprises a dedicated frequency counter configured to count a beat frequency from infrared detecting pixels thereof.

16. A machine vision system, comprising:

a camera, comprising;

a source of invisible light associated with the camera that changes in frequency during imaging and arranged to illuminate an object being imaged by the camera;

an imager;

a filter configured to selectively transmit visible light to selected pixels of the imager and configured to transmit invisible light supplied directly thereto from the source combined with invisible light reflected back from the object to other pixels of the imager; and

,

at least one device responsive to the imager a plurality of frequency counters, each respectively associated with a respective one of the invisible light filter elements and operable to measure the frequency of intensity modulations of the invisible light respectively transmitted there through.

17. A method of filtering light, the method comprising:

filtering a portion of a light beam through visible light filter elements of a filter;

filtering a portion of the same light beam through invisible light filter elements of the same filter; and

,

counting a beat frequency of the light respectively filtered by the invisible light filter elements with respective frequency counters.