Filter for use with imaging endoscopes

• US 20070015963A1
• Filed: 04/26/2006
• Published: 01/18/2007
• Est. Priority Date: 05/04/2005
• Status: Active Grant

• Current Assignee: Stryker European Operations Limited (Stryker Corporation)
• Original Assignee: Xillix Technologies Corp.
• Inventors: Fengler, John, Regamey, Francis
• Granted Patent: US 8,630,698 B2
• Time in Patent Office: Days
• US Class Current: 600/109
• CPC Class Codes: A61B 1/00006 of control signals
• CPC Class Codes: A61B 1/00009 of image signals during a use of endoscope
• CPC Class Codes: A61B 1/00045 Display arrangement
• CPC Class Codes: A61B 1/00101 the distal tip features being detachable
• CPC Class Codes: A61B 1/00186 with imaging filters
• CPC Class Codes: A61B 1/043 for fluorescence imaging
• CPC Class Codes: A61B 1/05 characterised by the image sensor, e.g. camera, being in the distal end portion
• CPC Class Codes: A61B 1/0638 providing two or more wavelengths
• CPC Class Codes: A61B 1/0646 with illumination filters
• CPC Class Codes: A61B 1/0655 Control therefor
• CPC Class Codes: A61B 1/0661 Endoscope light sources
• CPC Class Codes: G02B 23/2423 of the distal end
• CPC Class Codes: H04N 23/55 Optical parts specially adapted for electronic image sensors; Mounting thereof
• 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
• CPC Class Codes: H04N 23/56 provided with illuminating means

Abstract

A fluorescence endoscopy video system includes a multi-mode light source that produces light for white light and fluorescence imaging modes. A filter is positioned at the distal end of an imaging endoscope so that the endoscope can produce fluorescence and white light images of a tissue sample.

Claims

1. A filter assembly for use with an imaging endoscope, comprising:

a filter adapted to be positioned in front of an imaging lens of the endoscope, the filter blocking excitation light from reaching an image sensor of the endoscope so that the image-sensor can produce fluorescence images, the filter also passing an amount of blue light so that the image sensor can produce white light images of the tissue.

2. The filter assembly of claim 1, wherein the filter blocks excitation light having wavelengths in a range of 370-460 nm.

3. The filter assembly of claim 2, wherein the filter passes light having wavelengths in a range of >

460 nm.

4. The filter assembly of claim 1, further comprising means for securing the filter to a distal end of the endoscope.

5. The filter assembly of claim 4, wherein the means for securing the filter includes one or more tabs that are secured to the endoscope.

6. The filter assembly of claim 4, wherein the means for securing the filter includes an adhesive.

7. The filter assembly of claim 4, wherein the means for securing the filter includes a magnet.

8. The filter assembly of claim 4, wherein the means for securing the filter includes a sleeve that fits over a distal end of the endoscope.

9. The filter of claim 1, wherein the filter is made of a dye-impregnated polycarbonate film.

10. The filter of claim 9, wherein the filter is bonded to an imaging lens of an endoscope with an optically clear adhesive.

11. The filter of claim 9, wherein the dye is solvent yellow 33.

12. The filter of claim 11, wherein the dye has a concentration of 0.8%.

13. The filter of claim 12, wherein the filter passes light having wavelengths greater than 460 nm.

14. A system for producing fluorescence and white light images with an imaging endoscope that includes an image sensor, comprising:

a filter that is placed in front of an imaging lens of the endoscope that filters excitation light from reaching the image sensor and passes an amount of blue light;

an image processor that produces images from image signals received from the image sensor;

a light source for producing excitation light for use in a fluorescence imaging mode and illumination light for use in a white light imaging mode, wherein the illumination light produced by the light source is compensated such that the image signals produced from the image sensor can be white balanced.

15. The system of claim 14, wherein the illumination light produced by the light source consists of substantially equivalent proportions of blue light in a wavelength band that passes through the filter, green light and red light so that that the red, green and blue light received at the image sensor have substantially equal magnitudes when viewing a white surface.

16. The system of claim 14, wherein the light source produces an amount of reflectance light when operating in a fluorescence imaging mode.

17. The system of claim 16, wherein the reflectance light is red light.

18. The system of claim 16, wherein the reflectance light is green light.

19. The system of claim 16, wherein the reflectance light is blue light having wavelengths that pass through the filter.

20. The system of claim 14, wherein the image sensor is a color image sensor and the illumination light includes red, green and blue spectral components.

21. The system of claim 14, wherein the image sensor is a monochrome sensor and the illumination light includes sequentially produced red, green and blue spectral components.

22. A kit for use in converting an endoscope that performs white light imaging into an endoscope that performs white light and fluorescence imaging, comprising:

a filter adapted to be secured to the front of an imaging lens, the filter blocking an excitation light that causes tissue to produce fluorescence light but passing an amount of blue light as well as green and red light so that white light images produced from light collected by the endoscope can be white light balanced; and

an amount of adhesive for bonding the filter to the imaging lens of the endoscope.

23. The kit of claim 22, wherein the filter is made of a dye-impregnated polycarbonate.

24. The kit of claim 23, wherein the dye is solvent yellow 33.

25. The kit of claim 24, wherein the dye has a concentration of 0.8%.

26. The kit of claim 22, wherein the filter passes light having a wavelength greater than 460 nm.

27. A light source for producing excitation and illumination light for use with an endoscope having an image sensor that produces image signals of tissue and a blocking filter that prevents reflected excitation light from reaching the image sensor, comprising:

a lamp that produces light having wavelengths that will excite tissue to produce autofluorescence light and a red, green and blue illumination light for white light imaging; and

a color correction filter that adjusts the intensity of the illumination light so that reflected illumination light that passes through the blocking filter and reaches the image sensor has generally equal red, green and blue components so that the image signals produced by the image sensor can be white light balanced.