YCBCR pulsed illumination scheme in a light deficient environment

• US 10,277,875 B2
• Filed: 09/11/2017
• Issued: 04/30/2019
• Est. Priority Date: 07/26/2012
• Status: Active Grant

• Current Assignee: Depuy Synthes Products Incorporated (Johnson & Johnson)
• Original Assignee: Depuy Synthes Products Incorporated (Johnson & Johnson)
• Inventors: Blanquart, Laurent, Richardson, John
• Primary Examiner(s): Aynalem, Nathnael
• Application Number:
  US15/701,264
• Publication Number:
  US 20180014000A1
• Time in Patent Office: 596 Days
• CPC Class Codes: A61B 1/000095 for image enhancement
• CPC Class Codes: A61B 1/045 Control thereof
• CPC Class Codes: A61B 1/051 Details of CCD assembly
• CPC Class Codes: A61B 1/063 for monochromatic or narrow-band illumination
• CPC Class Codes: A61B 1/0638 providing two or more wavelengths
• CPC Class Codes: A61B 1/0655 Control therefor
• CPC Class Codes: F04C 2270/041 Controlled or regulated
• CPC Class Codes: H04N 1/6016 Conversion to subtractive colour signals
• CPC Class Codes: H04N 23/10 for generating image signals from different wavelengths
• CPC Class Codes: H04N 23/11 for generating image signals from visible and infrared light wavelengths
• CPC Class Codes: H04N 23/12 with one sensor only
• 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
• CPC Class Codes: H04N 23/74 by influencing the scene brightness using illuminating means
• CPC Class Codes: H04N 23/84 for processing colour signals
• CPC Class Codes: H04N 25/11 Arrangement of colour filter arrays [CFA]; Filter mosaics
• CPC Class Codes: H04N 25/70 SSIS architectures; Circuits associated therewith
• CPC Class Codes: H04N 25/75 Circuitry for providing, modifying or processing image signals from the pixel array
• CPC Class Codes: H04N 25/76 Addressed sensors, e.g. MOS or CMOS sensors
• CPC Class Codes: H04N 5/04 Synchronising for television systems using pulse code modulation H04N7/56
• CPC Class Codes: H04N 9/646 : for image enhancement, e.g. vertical detail restoration, cross-colour elimination, contour correction, chrominance trapping filters
• CPC Class Codes: H04N 9/77 : Circuits for processing the brightness signal and the chrominance signal relative to each other, e.g. adjusting the phase of the brightness signal relative to the colour signal, correcting differential gain or differential phase circuits for matrixing H04N9/67

Abstract

The disclosure extends to methods, systems, and computer program products for producing an image in light deficient environments with luminance and chrominance emitted from a controlled light source.

Claims

1. A digital imaging method for use with an endoscope in ambient light deficient environments comprising:

actuating an emitter to emit a pulse of a wavelength of electromagnetic radiation to cause illumination within the light deficient environment;

wherein the emitter comprises a plurality of sources that each emits a pulse of a portion of electromagnetic spectrum;

pulsing said emitter at a predetermined interval;

sensing reflected electromagnetic radiation from said pulse with a pixel array of an imaging sensor;

wherein said pixel array is actuated at a sensing interval that corresponds to the pulse interval of said emitter; and

synchronizing the emitter and the imaging sensor so as to produce a plurality of image frames wherein the plurality of image frames comprises a luminance frame comprising luminance image data and a chrominance frame comprising a modulated ChromaRed pulse and a modulated ChromaBlue pulse that are combined to form a color image, wherein a first buffer stores luminance modulated ChromaRed data and a second buffer stores the luminance modulated ChromaRed data and the luminance modulated ChromaBlue data, and wherein forming the color image includes subtracting luminance modulated ChromaRed data in the first buffer from luminance modulated ChromaBlue data in the second buffer.

2. The method of claim 1, further comprising actuating the plurality of sources simultaneously.

3. The method of claim 2, further comprising pulsing the plurality of sources at a predetermined interval.

4. The method of claim 1, further comprising adjusting the pulse to provide luminance information during the luminance frame, by matching to color space conversion coefficients.

5. The method of claim 1, further comprising adjusting the pulse to provide chrominance information during the chrominance frame to match to color space conversion coefficients.

6. The method of claim 1, further comprising pulsing the emitter to produce a pulsing pattern of luminance, chrominance blue, luminance, chrominance red.

7. The method of claim 1, further comprising pulsing the emitter to produce a pulsing pattern of luminance, chrominance blue combined with chrominance red, luminance, chrominance blue combined with chrominance red.

8. The method of claim 1, wherein the controller is configured to use chrominance frames more than once to reconstruct resultant frames.

9. The method of claim 1, wherein the method further comprises adding a luminance coefficient to chrominance frames by an image signal processor and wherein the luminance coefficient is an integer that is a multiple of (½

)ⁿ.

10. The method of claim 1, wherein the image sensor comprises uniform pixels configured to be read individually.

11. The method of claim 10, reading data from the image sensor at a plurality of frame durations wherein the plurality of frame durations produce long exposures and short exposures.

12. The method of claim 11, wherein the image sensor is configured to produce a sequence of frames comprising:

a luminance frame of long exposure pixel data and short exposure pixel data,

a red chrominance frame of long exposure pixel data and short exposure pixel data, and

a blue chrominance frame of long exposure pixel data and short exposure pixel data.

13. The method of claim 12, further comprising sensing the luminance wavelength so it is represented in the pattern twice as often as the red and blue chrominance wavelengths.

14. The method of claim 1, wherein a pulse of electromagnetic radiation emitted by the emitter is of a wavelength that is not visible to humans.

15. The method of claim 1, wherein the plurality of electromagnetic wavelengths comprises wavelengths that are visible to humans and that are not visible to humans.

16. The method of claim 1, actuating the emitter so as to emit the plurality of electromagnetic wavelengths at differing magnitudes.

17. The method of claim 16, wherein the differing magnitudes correspond to the imaging sensor'"'"'s sensitivity to differing wavelengths.

18. The method of claim 1, further comprising blanking said pixel array at a predetermined blanking interval that corresponds to said sensing interval.

19. The method of claim 1, further comprising subtracting a proportion of luminance data from the luminance frames from the first buffer and the second buffer.