Device and method for reducing effects of video artifacts

• US 8,310,530 B2
• Filed: 05/21/2007
• Issued: 11/13/2012
• Est. Priority Date: 05/19/2006
• Status: Active Grant

• Current Assignee: PSIP, LLC
• Original Assignee: Avantis Medical Systems, Inc.
• Inventors: Bayer, Lex, Niel, Alex, Okas, Robert
• Primary Examiner(s): Backer, Firmin
• Assistant Examiner(s): BUI, JONATHAN A
• Application Number:
  US11/751,597
• Publication Number:
  US 20070279486A1
• Time in Patent Office: 2,003 Days
• Field of Search: 348/65, 348/72
• US Class Current: 348/65
• CPC Class Codes: A61B 1/00006 of control signals
• CPC Class Codes: A61B 1/000094 extracting biological structures
• CPC Class Codes: A61B 1/0005 combining images e.g. side-by-side, superimposed or tiled
• CPC Class Codes: A61B 1/00179 for off-axis viewing
• CPC Class Codes: A61B 1/00181 for multiple fixed viewing angles A61B1/00193 takes precedence
• CPC Class Codes: A61B 1/005 Flexible endoscopes
• CPC Class Codes: A61B 1/0051 with controlled bending of insertion part
• CPC Class Codes: A61B 1/0125 Endoscope within endoscope
• CPC Class Codes: A61B 1/045 Control thereof
• CPC Class Codes: A61B 1/05 characterised by the image sensor, e.g. camera, being in the distal end portion
• CPC Class Codes: A61B 1/0625 for multiple fixed illumination angles
• CPC Class Codes: A61B 1/0655 Control therefor
• CPC Class Codes: A61B 1/0676 at distal tip of an endoscope
• CPC Class Codes: G02B 23/2423 of the distal end

Abstract

A method for reducing an effect of a video artifact includes adjusting a phase of a second imaging device'"'"'s video clock signal so that a phase of the second imaging device'"'"'s video synchronization signal matches a phase of a first imaging device'"'"'s video synchronization signal. An endoscopic system includes a first imaging device, a second imaging device, a light source, and a controller that reduces an artifact in an image produced by the first imaging device. In some embodiments, the first imaging device faces the light source.

Claims

1. A controller configured for use with an endoscopic system, the controller comprising:

a phase lock loop circuit that is configured to receive a video synchronization signal from a first imaging sensor and to receive a video synchronization signal from a second imaging sensor to generate a video clock signal to send to the second imaging sensor, wherein the video clock signal is generated such that image frames of the imaging sensors have the same fundamental frequency and are phase locked, and wherein the first imaging sensor and a first light source face the second imaging sensor and a second light source; and

a light source driver adapted to be connected to the second light source, wherein the light source driver is further connected to the phase lock loop circuit to receive the video clock signal, and wherein the first imaging sensor and the first light source are configured to be activated during a first time interval, and wherein the second imaging sensor and second light source are configured to be activated during a second time interval that is distinct from the first time interval.

2. The controller of claim 1, wherein the controller is configured to lock a selected phase difference between the video clock signal and the first imaging sensor'"'"'s video synchronization signal.

3. The controller of claim 1, wherein the light source driver is configured to drive the second light source for only a portion of a full duty cycle.

4. The controller of claim 1, wherein the light source driver is configured to adjust the location of an image artifact of the first imaging sensor by adjusting a phase difference between the video clock signal and the video synchronization signal of the first imaging sensor.

5. The controller of claim 1, wherein the light source driver is configured to decrease the duty cycle of the second light source to reduce the size of an image artifact of the first imaging sensor.

6. The sensor of claim 1, wherein the light source driver is configured to activate the second light source only when the first imaging sensor is in a vertical blanking interval.

7. An endoscopic system comprising:

a first imaging sensor;

a first light source;

a second imaging sensor;

a second light source, wherein the first imaging sensor and first light source face the second imaging sensor and second light source; and

a controller including a phase lock loop circuit that is configured to receive a video synchronization signal from the first imaging sensor and to receive a video synchronization signal from the second imaging sensor to generate and adjust a video clock signal such that the second light source and the image frames of the first and second imaging sensors have the same fundamental frequency and are phase locked, wherein the first imaging sensor and first light source are activated during a first interval of the frame period, and wherein the second imaging sensor and second light source are activated during a second interval of the frame period that is distinct from the first interval.

8. The endoscopic system of claim 7, wherein a phase difference between the second imaging sensor'"'"'s video synchronization signal and the first imaging sensor'"'"'s video synchronization signal is not zero.

9. The endoscopic system of claim 7, wherein the controller is configured to adjust the location of an image artifact of the first image sensor.

10. The endoscopic system of claim 7, wherein the controller is configured to reduce the size of an image artifact of the first imaging sensor by decreasing the duty cycle of the second light source.

11. The endoscopic system of claim 7, wherein the second light source is activated only when the first imaging sensor is in a vertical blanking interval.

12. The endoscopic system of claim 7, wherein the controller further comprises

a light source driver adapted to be connected to the second light source, wherein the light source driver is connected to the phase lock loop circuit to receive the video clock signal and configured to activate the second light source relative to the video clock signal.

13. The endoscopic system of claim 12, wherein the light source driver is configured to adjust the location of an image artifact of the first imaging sensor by adjusting a phase difference between the video clock signal and the video synchronization signal of the first imaging sensor.

14. The endoscopic system of claim 13, wherein the light source driver is configured to move the artifact vertically.

15. The endoscopic system of claim 12, wherein the light source driver is configured to reduce the size of an imaging artifact of the first imaging sensor by decreasing the duty cycle of the second light source.

16. The endoscopic system of claim 12, wherein the light source driver is configured to activate the second light source only when the first imaging sensor is in a vertical blanking interval.

17. The system of claim 7, wherein the frame frequency is sufficiently high such that eyes cannot sense that the first and second imaging sensors and their light sources are intermittently activated.

18. The endoscopic system of claim 7, wherein the controller is configured to lock a selected phase difference between the video clock signal and the video synchronization signal of the first imaging sensor.

19. The endoscopic system of claim 7, further comprising a light source driver, wherein the light source driver is connected to the phase lock loop circuit to receive the video clock signal.

20. The endoscopic system of claim 19, wherein the light source driver is configured to adjust the location of an image artifact of the first imaging sensor by adjusting a phase difference between the video clock signal and the video synchronization signal of the first imaging sensor.

21. The endoscopic system of claim 19, wherein the light source driver activates the second light source for only a portion of a full duty cycle.

22. The endoscopic system of claim 7, wherein the first light source is configured to be activated only when the first imaging sensor is acquiring an image, and wherein the second light source is configured to be activated only when the second imaging sensor is acquiring an image.

23. The endoscopic system of claim 7, wherein the controller is configured such that the first imaging sensor acquires an image and the first light source is activated during one half of the frame period, and wherein the second imaging sensor acquires an image and the second light source is activated during the other half of the frame period.

24. The endoscopic system of claim 19, wherein the light source driver is configured to reduce a size of an image artifact of the first imaging sensor by decreasing the duty cycle of the second light source.

25. A method for reducing light interference between a first imaging sensor and a second light source and a second imaging sensor and a first light source of an endoscopic system, wherein the first imaging sensor and the first light source face the second imaging sensor and the second light source, the method comprising:

using a phase lock loop circuit to receive a video synchronization signal from the first imaging sensor and to receive a video synchronization signal from the second imaging sensor and to generate and adjust a video clock signal for the second imaging sensor so that image frames of the first and second imaging sensors have the same fundamental frequency and are phase locked; and

activating the first imaging sensor and first light source during a first interval of the frame period, and activating the second imaging sensor and second light source during a second interval of the frame period that is distinct from the first interval.

26. The method of claim 25, further comprising locking a selected phase difference between the video clock signal and the first imaging sensor'"'"'s video synchronization signal.

27. The method of claim 25, further comprising adjusting the location of an image artifact of the first imaging sensor by adjusting a phase difference between the video clock signal and the video synchronization signal of the first imaging sensor.

28. The method of claim 27, wherein adjusting the phase difference moves the artifact vertically.

29. The method of claim 25, further comprising reducing the size of an image artifact of the first imaging sensor by decreasing the duty cycle of the second light source.

30. The method of claim 25, wherein the second light source is activated only when the first imaging sensor is in a vertical blanking interval.