Precision endoscopic imaging system

• US 6,448,545 B1
• Filed: 01/18/2000
• Issued: 09/10/2002
• Est. Priority Date: 01/18/2000
• Status: Expired due to Fees

• Current Assignee: Synchrotronics Company
• Original Assignee: Synchrotronics Company
• Inventors: Chen, Min
• Primary Examiner(s): ALLEN, STEPHONE B
• Application Number:
  US09/483,005
• Time in Patent Office: 966 Days
• Field of Search: 250/207, 250/208.1, 250/214.VT, 250/310, 250/332, 250/336.1, 250/214.1
• US Class Current: 250/214.0VT
• CPC Class Codes: A61B 1/00186 with imaging filters
• CPC Class Codes: A61B 1/00193 adapted for stereoscopic vision
• CPC Class Codes: A61B 1/042 characterised by a proximal camera, e.g. a CCD camera
• CPC Class Codes: A61B 5/0073 by tomography, i.e. reconstruction of 3D images from 2D projections A61B5/0066 takes precedence
• CPC Class Codes: A61B 5/0084 for introduction into the body, e.g. by catheters A61B5/1459 takes precedence
• CPC Class Codes: H04N 23/555 for picking-up images in sites, inaccessible due to their dimensions or hazardous conditions, e.g. endoscopes or borescopes

Abstract

An imaging system is disclosed for use in low-light environments or environments where low-levels of such radiation is desirable. Examples of such environments are endoscopy, laparoscopy, mammography and night photography. In the case of radiation that is other than visible light, a radiation converter and method for fabricating same is disclosed. The radiation converter comprises a film of heavy scintillator (e.g. CdWO₄) coated on a fiber optical window to efficiently convert the radiation into visible light. The visible light is passed into a signal amplifier employing a focussing electron-bombarded charge-couple device (FEBCCD) or a focussing electron-bombarded complementary metal-oxide semiconductor (FEBCMOS) to amplify the signal. Novel methods of performing three-dimension imaging using this system as well as removing the effects of high-speed movement are also disclosed.

Claims

1. An imaging system, comprising,

a radiation source having a first wavelength emission;

a first conduit providing a path for radiation between said radiation source and a selected imaging object;

an electromagnetic focussing imaging detector providing an output signal in response to an applied optical image, wherein said magnetically focussed image detector comprises;

a photocathode disposed to receive photons and provide electrons corresponding to the intensity of the received photons,

one of a CCD and a CMOS detector disposed a selected distance from said photocathode to receive said electrons,

means for urging said electrons toward said one of a CCD and a CMOS detector from said photocathode, and

a magnetic field source disposed to provide a magnetic field along said selected distance, wherein said electrons are caused to move in a helical path toward said one of a CCD and a CMOS detector of selected radius change; and

a second conduit for applying said optical image to said focussing imaging detector from said selected imaging object.

2. The imaging system of claim 1, wherein said radiation source comprises a light source.

3. The imaging system of claim 2, wherein said light source comprises one of a white light, an ultra violet light, a selectively filtered mercury light, selectively filtered xenon light, a near infrared light and selected wavelength laser light source.

4. The imaging system of claim 3, wherein said light source provides one of a 310-430 nm wavelength visible and a near IR (about 700 nm) light emission.

5. The imaging system of claim 1, further including a tunable wavelength filter disposed between said second conduit and said focussing imaging detector to provide a selectively filtered optical image to said focussing imaging detector.

6. The imaging system of claim 5, wherein said tunable wavelength filter selectively provides one of a red and a non-red image to said focussing imaging detector.

7. The imaging system of claim 6, further comprising means for comparing said red and said non-red signal, and providing an indication of the presence of a disease condition of said selected imaging object.

8. The imaging system of claim 1, wherein said first and said second conduits comprise a fiber-optic probe having corresponding first and second portions, said second portion corresponding to said second conduit having an array of optical fibers.

9. The imaging system of claim 8, wherein said fiber-optic probe further includes an annular tube connected to a controllable vacuum for evacuating extraneous matter present in the region of the end of said probe.

10. The imaging system of claim 1, wherein said first conduit illuminates said selected imaging object, and said'"'"'second conduit receives an optical image from radiation transmitted through said selected imaging object.

11. The imaging system of claim 1, wherein said, second conduits comprises a plurality of second conduits adapted to provide a plurality of optical images to said focussing imaging detector from said selected imaging object.

12. The imaging system of claim 1, further including a image deflector connected to said second conduit to provide a selected plurality of images to said focussing imaging detector of said selected imaging object.

13. The imaging system of claim 1, further including an image processor connected to receive said output signal from said focussing image detector and provide a signal corresponding to an image representing said selected imaging object, said image processor further including blur-removal means for removing image artifacts caused by movement of at least said second conduit over said selected imaging object.

14. The imaging system of claim 1, wherein said focussing imaging detector comprises one of a FEBCCD and a EBCMOS detector.

15. The imaging system of claim 14 configured and disposed to provide an endoscopic imaging system.

16. The imaging system of claim 1, further comprising means for suppressing positive ion feedback.

17. A magnetically focussed image detector comprising:

a photocathode disposed to receive photons and provide electrons corresponding to the intensity of the received photons;

one of a CCD and a CMOS detector disposed a selected distance from said photocathode to receive said electrons;

means for urging said electrons toward said one of a CCD and a CMOS detector from said photocathode; and

a magnetic field source disposed to provide a magnetic field along said selected distance, wherein said electrons are caused to move in a helical path toward said one of a CCD and a CMOS detector of selected radius change.

18. The magnetically focussed image detector of claim 17, wherein the radius of curvature of said helical electron path is selected to decrease in proximity to the CCD or CMOS detector.

19. A reduced ion positive feedback detector comprising:

one of a CCD and a CMOS detector disposed a selected distance from said means for providing electrons to receive said electrons;

means for providing electrons to said one of said CCD and said CMOS detector along a path according to a selected signal;

a magnetic field source disposed to provide a magnetic field along said selected distance, wherein said electrons are caused to move in a helical path toward said on of said CCD and said CMOS detector of selected radius change.

20. A method of eliminating positive ion feedback, comprising the steps of:

applying electrons to one of a CCD and a CMOS detector along a first axis from a source; and

applying a magnetic field along said first axis in vicinity of said one of said CCD and said CMOS detector, wherein ions generated by the impact of said electrons on the one of said CCD and said CMOS detector travel on a path divergent from said source and said first axis.