SCANNING BEAM IMAGING WITH ADJUSTABLE DETECTOR SENSITIVITY OR GAIN

• US 20080173803A1
• Filed: 01/18/2007
• Published: 07/24/2008
• Est. Priority Date: 01/18/2007
• Status: Active Grant

• Current Assignee: Ethicon Endo-Surgery, Inc. (Johnson & Johnson)
• Original Assignee: Ethicon Endo-Surgery, Inc. (Johnson & Johnson)
• Inventors: Dunki-Jacobs, Robert J.
• Granted Patent: US 7,589,316 B2
• Time in Patent Office: Days
• US Class Current: 250/234
• CPC Class Codes: A61B 1/00098 Deflecting means for inserted tools
• CPC Class Codes: A61B 1/00183 for variable viewing angles
• CPC Class Codes: A61B 1/045 Control thereof

Abstract

A scanning beam assembly comprising: a beam generator to generate a beam of radiation, an oscillating reflector configured to deflect the beam at varying angles of excursion to yield a scanned beam that scans a field of view, an optical detector that detects light reflected from the field of view, the detector including at least one of an adjustable gain and adjustable sensitivity, and a controller programmable to control the gain and/or sensitivity of the detector.

Claims

1. In a scanning beam assembly comprising:

a beam generator to generate a beam of radiation,

an oscillating reflector configured to deflect the beam at varying angles of excursion to yield a scanned beam that scans a field of view,

an optical detector that detects light reflected from the field of view, the detector including at least one of an adjustable gain and adjustable sensitivity, and

a controller programmable to control the gain and/or sensitivity of the detector.

2. The scanning beam assembly of claim 1 wherein the beam assembly includes a partially reflective surface that reflects the beam of radiation from the beam generator to the oscillating reflector and the controller is programmed to increase the sensitivity of the detector when the scanned beam intersects the partially reflective surface.

3. The scanning beam assembly of claim 1 wherein the controller is programmed to increase the gain of the detector when the scanned beam is reflected at wide angles of excursion within the field of view.

4. The scanning beam assembly of claim 3 wherein the controller is programmed to increase the gain of the detector when the scanned beam is reflected at an angle greater than about 25 degrees.

5. The scanning beam assembly of claim 1 wherein the controller is programmed to increase the gain of the detector when the scanned beam is reflected at its wider angles of excursion and to increase the sensitivity of the detector when the scanned beam intersects the partially reflective surface.

6. The scanning beam assembly of claim 5 wherein the controller is programmed to increase the gain of the detector when the scanned beam is reflected at an angle greater than about 25 degrees.

7. The scanning beam assembly of claim 1 wherein the detector includes a detector element and a means for adjusting the gain or sensitivity of the detector.

8. The scanned beam assembly of claim 7 wherein the means for adjusting the gain or sensitivity of the detector is selected from the group consisting of a variable gain amplifier, a controllable power source, or a combination thereof.

9. The scanning beam assembly of claim 8 wherein the detector includes a detector element selected from the group consisting of a PMT, CCD, photodiode, an avalanche photodiode, and amorphous silicon.

10. The scanning beam assembly of claim 7 wherein the oscillating reflector includes a MEMS scanner and a concave optic.

11. The scanning beam assembly of claim 10 wherein the assembly forms part of a scanning beam imager or a scanning beam illuminator.

12. The scanning beam assembly of claim 11 wherein the controller is programmable based on the oscillating scan path of the reflector.

13. The scanning beam assembly of claim 12 wherein the assembly includes a partially reflective surface that reflects the beam of radiation from the beam generator to the oscillating reflector and the controller is programmed to increase the sensitivity of the detector when the scanned beam intersects the partially reflective surface.

14. The scanning beam assembly of claim 13 wherein the controller is programmed to increase the gain of the detector when the scanned beam is reflected at angles greater than about 25 degrees.

15. A scanned beam endoscope comprising:

an endoscope, and a scanning beam assembly including;

a beam generator to generate a beam of radiation,

an oscillating reflector configured to deflect the beam and to yield a scanned beam that scans a field of view,

an optical detector that detects light reflected from the field of view, the detector including at least one of an adjustable gain and sensitivity, and

a controller programmable to control the gain and/or sensitivity of the detector.

16. The endoscope of claim 15 wherein the beam assembly includes a partially reflective surface that reflects the beam of radiation from the beam generator to the oscillating reflector and the controller is programmed to increase the sensitivity of the detector when the scanned beam intersects the partially reflective surface.

17. The endoscope of claim 15 wherein the controller is programmed to increase the gain of the detector when the scanned beam is reflected at wide angles of excursion.

18. The endoscope of claim 17 the controller is programmed to increase the gain of the detector when the scanned beam is reflected at an angle greater than about 20 degrees.

19. The endoscope of claim 15 wherein the controller is programmed to increase the gain of the detector when the scanned beam is reflected at its wider angles of excursion and to increase the sensitivity of the detector when the scanned beam intersects the partially reflective surface.

20. The endoscope of claim 15 wherein the detector includes a detector element and a means for adjusting the gain or sensitivity of the detector.

21. The endoscope of claim 20 wherein the means for adjusting the gain or sensitivity of the detector is selected from the group consisting of a variable gain amplifier, a controllable power source, or a combination thereof.

22. A scanning endoscope tip comprising

a beam generator to generate a beam of radiation,

an oscillating reflector configured to deflect the beam and to yield a scanned beam that scans a field of view,

an optic, the oscillating reflector reflecting the scanned beam through the opitic to the field of view,

an optical detector that detects light reflected from the field of view, the detector including at least one of an adjustable gain and sensitivity, and

a controller programmable to control the gain and/or sensitivity of the detector.

23. A method for controlling a scanning beam assembly including:

a beam generator that generates a beam of radiation,

an oscillating reflector configured to deflect the beam and to yield a scanned beam that scans a field of view,

an optic, the oscillating reflector reflecting the scanned beam through the opitic to the field of view,

an optical detector that detects light reflected from the field of view, the detector including at least one of an adjustable gain and sensitivity, and

a controller programmable to control the gain and/or sensitivity of the detector;

wherein the method comprises the steps of

generating a beam of radiation,

scanning the beam of radiation across the field of view,

increasing the sensitivity and/or the gain of the detector, when the beam is addressing a point in the field of view having a low SNR,

detecting the reflectance from the field of view and generating an imaging signal.