Systems and methods for medical imaging using a rolling shutter imager

Patent metadata

Field	Value
Publication number	US-11638517-B2
Application number	US-202016745154-A
Country	US
Kind code	B2
Filing date	Jan 16, 2020
Priority date	Jan 17, 2019
Publication date	May 2, 2023
Grant date	May 2, 2023

Abstract

A method of imaging tissue of a subject using an electronic rolling shutter imager includes sequentially resetting rows of pixels of the rolling shutter imager from a first row to a last row, sequentially reading charge accumulated at the rows of pixels from the first row to the last row, wherein the first row is read after resetting the last row, illuminating the tissue of the subject with illumination light for an illumination period that lasts longer than a vertical blanking period, wherein the vertical blanking period is the period from the resetting of the last row to the reading of the first row, and generating an image frame from the readings of charge accumulated at the rows of pixels, wherein at least one reading of charge accumulated at a row of pixels is removed or replaced to generate the image frame.

First claim

The invention claimed is:

1. A method of imaging tissue of a subject using an electronic rolling shutter imager, the method comprising:
sequentially resetting rows of pixels of the rolling shutter imager from a first row to a last row;
sequentially reading charge accumulated at the rows of pixels from the first row to the last row, wherein the first row is read after resetting the last row;
illuminating the tissue of the subject with illumination light for an illumination period that lasts longer than a vertical blanking period, wherein the vertical blanking period is the period from the resetting of the last row to the reading of the first row; and
generating an image frame from the readings of charge accumulated at the rows of pixels, wherein at least one reading of charge accumulated at a row of pixels is removed or replaced to generate the image frame.

2. The method of claim 1 , wherein the illumination period begins prior to the resetting of the last row.

3. The method of claim 1 , wherein the illumination period ends after the reading of the first row.

4. The method of claim 1 , wherein the illumination period begins at least when the vertical blanking period begins.

5. The method of claim 1 , wherein the illumination period ends at least when the vertical blanking period ends.

6. The method of claim 1 , wherein at least a reading of charge accumulated at the first row of pixels is removed or replaced to generate the image frame.

7. The method of claim 1 , wherein at least a reading of charge accumulated at the last row of pixels is removed or replaced to generate the image frame.

8. The method of claim 1 , wherein the at least one reading of charge accumulated at a row of pixels is replaced by at least one predetermined value to generate the image frame.

9. The method of claim 1 , wherein at least one reading of charge accumulated at a row of pixels is removed by cropping to generate the image frame.

10. The method of claim 1 , wherein the tissue of the subject is illuminated with visible light and the method further comprises illuminating the tissue of the subject with fluorescence excitation light at least during a subsequent vertical blanking period and generating a fluorescence image frame based on light emitted from the tissue of the subject in response to the fluorescence excitation light.

11. The method of claim 10 , further comprising administering a fluorescence imaging agent to the subject prior to generating the fluorescence image frame.

12. The method of claim 10 , comprising illuminating the tissue of the subject with fluorescence excitation light and visible illumination light simultaneously during the illumination period.

13. The method of claim 1 , wherein illuminating the tissue of the subject with illumination light comprises pulsing the illumination light.

14. The method of claim 13 , comprising controlling a pulse width of the pulsed illumination light based on readings of charge accumulated at the rows of pixels during a previous frame.

15. The method of claim 1 , wherein the illumination light is generated by at least one LED.

16. The method of claim 1 , wherein the rolling shutter imager is part of an endoscopic imager.

17. The method of claim 1 , wherein the rolling shutter imager comprises a mechanical shutter and the mechanical shutter remains at least partially open from before the illumination period begins until after the illumination period ends.

18. The method of claim 17 , further comprising reducing an amount of light received at the rolling shutter imager by operating the mechanical shutter.

19. The method of claim 1 , further comprising adjusting a gain of the rolling shutter imager based on readings of charge accumulated at the rows of pixels during a previous frame.

Assignees

• Stryker Corp

Inventors

• Chang William Huei Liang
• Larson Bryan
• Shen John
• FEINGOLD Benjamin
• Ramesh Ajay

Classifications

• G06T2207/10068

  Endoscopic image · CPC title

• A61B1/000095

  for image enhancement · CPC title

• H04N23/555

  for picking-up images in sites, inaccessible due to their dimensions or hazardous conditions, e.g. endoscopes or borescopes · CPC title

• G06T2207/30004

  Biomedical image processing · CPC title

• A61B5/0071

  by measuring fluorescence emission · CPC title