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United States Patent

Patent No.:

11,102,400

Date of Patent:

Aug. 26, 2021


Title
Pulsed illumination in a fluorescence imaging system
Abstract
Pulsed fluorescence imaging in a light deficient environment is disclosed. A system includes an emitter for emitting pulses of electromagnetic radiation and an image sensor comprising a pixel array for sensing reflected electromagnetic radiation. The system includes a controller configured to synchronize timing of the emitter and the image sensor. The system is such that at least a portion of the pulses of electromagnetic radiation emitted by the emitter comprises electromagnetic radiation having a wavelength from about 770 nm to about 790 nm.
Claims

What is claimed is:

1. A system for providing visualization in a light deficient environment, the system comprising: an endoscope; a waveguide attached to the endoscope; an emitter for emitting pulses of electromagnetic radiation, wherein the emitter comprises a plurality of electromagnetic sources, and wherein the plurality of electromagnetic sources comprises a fluorescence source for emitting a fluorescence excitation pulse comprising electromagnetic radiation having a wavelength from 770 nm to 790 nm; an image sensor comprising a pixel array for sensing reflected electromagnetic radiation; a controller in electronic communication with the image sensor and the emitter configured to synchronize timing of the emitter and the image sensor to generate a plurality of exposure frames comprising a luminance exposure frame, a red chrominance exposure frame, a blue chrominance exposure frame, and a fluorescence exposure frame, and wherein the controller is further configured to control one or more of: a blanking period of the image sensor or one or more of a pulse length or intensity of the pulses of electromagnetic radiation emitted by the emitter based on a carrying capacity of the waveguide; wherein the luminance exposure frame, the red chrominance exposure frame, the blue chrominance exposure frame, and the fluorescence exposure frame are used to form a color image frame with fluorescence image data.

2. The system of claim 1, wherein the pixel array comprises a plurality of pixels, and wherein a sensitivity of each of the plurality of pixels can be controlled by the controller such that the pixel array comprises long exposure pixels and short exposure pixels.

3. The system of claim 1, wherein: the luminance exposure frame comprises long exposure pixel data and short exposure pixel data; the red chrominance exposure frame comprises long exposure pixel data and short exposure pixel data; and the blue chrominance exposure frame comprises long exposure pixel data and short exposure pixel data.

4. The system of claim 1, wherein the emitter modulates the pulses of electromagnetic radiation to provide luminance information according to color transformation coefficients that convert light energy from red, green, and blue light energy space to luminance, blue chrominance, and red chrominance light energy space.

5. The system of claim 1, wherein the emitter modulates the pulses of electromagnetic radiation to provide chrominance information according to color transformation coefficients that convert light energy from red, green, and blue light energy space to luminance, blue chrominance, and red chrominance light energy space.

6. The system of claim 1, wherein the pulses of electromagnetic radiation are emitted according to a pulsing pattern comprising a green pulse, a blue pulse, a red pulse, and the fluorescence excitation pulse.

7. The system of claim 1, wherein the pulses of electromagnetic radiation are emitted according to a pulsing pattern comprising a green pulse, a combined red and blue pulse, and the fluorescence excitation pulse.

8. The system of claim 1, wherein the controller is configured to generate a video stream comprising a plurality of image frames, wherein at least a portion of the plurality of image frames comprises data captured by the pixel array in response to a pulse of green electromagnetic radiation, a pulse of blue electromagnetic radiation, a pulse of red electromagnetic radiation, and the fluorescence excitation pulse comprising the electromagnetic radiation having the wavelength from 770 nm to 790 nm.

9. The system of claim 1, wherein the image sensor is configured to generate each of the plurality of exposure frames in response to a pulse of electromagnetic radiation emitted by the emitter.

10. The system of claim 9, wherein the pixel array of the image sensor senses reflected electromagnetic radiation to generate the plurality of exposure frames during a readout period of the pixel array, wherein the readout period is a duration of time when active pixels in the pixel array are read.

11. The system of claim 1, wherein the pulses of electromagnetic radiation are emitted according to a pulsing pattern comprising a luminance pulse, a red chrominance pulse, a blue chrominance pulse, and a fluorescence excitation pulse, wherein the luminance pulse is represented in the pulsing pattern twice as often as the red chrominance pulse, the blue chrominance pulse, or the fluorescence excitation pulse.

12. The system of claim 1, wherein at least a portion of the pulses of electromagnetic radiation emitted by the emitter is the fluorescence excitation pulse for fluorescing a reagent, wherein the fluorescence excitation pulse comprises the electromagnetic radiation having the wavelength from 770 nm to 790 nm.

13. The system of claim 1, wherein the emitter is configured to emit, during a pulse duration, a plurality of sub-pulses of electromagnetic radiation having a sub-duration shorter than the pulse duration.

14. The system of claim 1, wherein one or more of the pulses of electromagnetic radiation emitted by the emitter comprises electromagnetic radiation emitted at two or more wavelengths simultaneously as a single pulse or a single sub-pulse.

15. The system of claim 1, wherein at least a portion of the pulses of electromagnetic radiation emitted by the emitter is the fluorescence excitation pulse that results in the fluorescence exposure frame created by the image sensor, and wherein the controller is configured to provide the fluorescence exposure frame to a corresponding system that determines a location of a tissue structure within a scene based on the fluorescence exposure frame.

16. The system of claim 15, wherein the fluorescence excitation pulse comprises the electromagnetic radiation having the wavelength from 770 nm to 790 nm.

17. The system of claim 15, wherein the controller is further configured to: receive the location of the tissue structure from the corresponding system; generate an overlay frame comprising the location of the tissue structure; and combine the overlay frame with the color image frame depicting the scene to indicate the location of the tissue structure within the scene.

18. The system of claim 17, wherein the structure comprises one or more of a nerve, a ureter, a blood vessel, an artery, a blood flow, or a tumor.

19. The system of claim 1, wherein the controller is configured to synchronize timing of the pulses of electromagnetic radiation during a blanking period of the image sensor, wherein the blanking period corresponds to a time between a readout of a last row of active pixels in the pixel array and a beginning of a next subsequent readout of active pixels in the pixel array.

20. The system of claim 1, wherein two or more pulses of electromagnetic radiation emitted by the emitter result in two or more instances of reflected electromagnetic radiation that are sensed by the pixel array to generate two or more exposure frames that are combined to form an image frame.

21. The system of claim 1, wherein the image sensor comprises a first image sensor and a second image sensor such that the image sensor can generate a three-dimensional image.

22. The system of claim 1, wherein the emitter is configured to emit a sequence of pulses of electromagnetic radiation repeatedly sufficient for generating a video stream comprising the plurality of image frames, wherein each image frame in the video stream comprises data from a plurality of exposure frames, and wherein each of the plurality of exposure frames corresponds to a pulse of electromagnetic radiation.

23. The system of claim 1, wherein the pulses of electromagnetic radiation are emitted in a pattern of varying wavelengths of electromagnetic radiation, and wherein the emitter repeats the pattern of varying wavelengths of electromagnetic radiation.

24. The system of claim 1, wherein at least a portion of the pulses of electromagnetic radiation comprise a red wavelength, a green wavelength, a blue wavelength, and a fluorescence excitation wavelength such that reflected electromagnetic radiation sensed by the pixel array corresponding to each of the red wavelength, the green wavelength, the blue wavelength, and the fluorescence excitation wavelength can be processed to generate a Red-Green-Blue (RGB) image frame comprising an overlay of fluorescence imaging data, wherein the fluorescence excitation wavelength of electromagnetic radiation comprises the electromagnetic radiation having the wavelength from 770 nm to 790 nm.

25. The system of claim 1, wherein at least a portion of the pulses of electromagnetic radiation comprise a luminance emission, a red chrominance emission, a blue chrominance emission, and a fluorescence excitation emission such that reflected electromagnetic radiation sensed by the pixel array corresponding to each of the luminance emission, the red chrominance emission, the blue chrominance emission, and the fluorescence excitation emission can be processed to generate a YCbCr image frame comprising an overlay of fluorescence imaging data, wherein the fluorescence excitation emission of electromagnetic radiation comprises the electromagnetic radiation having the wavelength from 770 nm to 790 nm.

26. The system of claim 1, further comprising a filter that filters electromagnetic radiation having a wavelength from 770 nm to 790 nm.

27. The system of claim 1, wherein the controller further controls: one or more of the pulse length or intensity of the pulses of electromagnetic radiation emitted by the emitter based power output capability of the emitter; or the blanking period of the image sensor based on the power output capability of the emitter.