Single image sensor for capturing mixed structured-light images and regular images

• US 10,447,950 B2
• Filed: 01/16/2018
• Issued: 10/15/2019
• Est. Priority Date: 10/16/2015
• Status: Active Grant

• Current Assignee: CapsoVision, Inc.
• Original Assignee: CapsoVision, Inc.
• Inventors: Wang, Kang-Huai, Xu, Yi, Wilson, Gordon C., Wu, Chenyu
• Primary Examiner(s): Elahi, Shan E
• Application Number:
  US15/871,991
• Publication Number:
  US 20180160061A1
• Time in Patent Office: 637 Days
• Field of Search: 348 76
• CPC Class Codes: A61B 1/00009 of image signals during a use of endoscope
• CPC Class Codes: A61B 1/041 Capsule endoscopes for imaging
• CPC Class Codes: A61B 1/06 with illuminating arrangements
• CPC Class Codes: A61B 1/0605 for spatially modulated illumination
• CPC Class Codes: G01B 11/2513 with several lines being projected in more than one direction, e.g. grids, patterns
• CPC Class Codes: G02B 23/2415 Stereoscopic endoscopes
• CPC Class Codes: G02B 23/2484 Arrangements in relation to a camera or imaging device processing or control of video signals generated by an endoscope H04N23/60, H04N23/70
• CPC Class Codes: H04N 13/271 wherein the generated image signals comprise depth maps or disparity maps
• CPC Class Codes: H04N 13/286 having separate monoscopic and stereoscopic modes
• CPC Class Codes: H04N 13/296 Synchronisation thereof; Control 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 25/533 by using differing integration times for different sensor regions
• CPC Class Codes: H04N 25/534 depending on the spectral component
• CPC Class Codes: H04N 25/587 acquired sequentially, e.g. using the combination of odd and even image fields
• CPC Class Codes: H04N 25/589 with different integration times, e.g. short and long exposures
• CPC Class Codes: H04N 25/59 by controlling the amount of charge storable in the pixel, e.g. modification of the charge conversion ratio of the floating node capacitance
• 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

Abstract

An integrated image sensor for capturing a mixed structured-light image and regular image using an integrated image sensor are disclosed. The integrated image sensor comprises a pixel array, one or more output circuits, one or more analog-to-digital converters, and one or more timing and control circuits. The timing and control circuits are arranged to perform a set of actions including capturing a regular image and a structured-light image. According to the present invention, the structured-light image captured before or after the regular image is used to derive depth or shape information for the regular image. An endoscope based on the above integrated image sensor is also disclosed. The endoscope may comprises a capsule housing adapted to be swallowed, where the components of integrated image sensor, a structured light source and a non-structured light source are enclosed and sealed in the capsule housing.

Claims

1. An integrated image sensor, comprising:

a pixel array being responsive to light energy received by the pixel array to produce pixel signals having a voltage level depending on the light energy received by the pixel array;

one or more output circuits coupled to the pixel array to access the pixel signals produced by the pixel array;

one or more analog-to-digital converters having a first dynamic range and a second dynamic range, wherein the first dynamic range is lower than the second dynamic range;

one or more timing and control circuits coupled to the pixel array, said one or more output circuits, said one or more analog-to-digital converters or a combination thereof, wherein said one or more timing and control circuits are arranged to;

capture, by the pixel array, a structured-light image formed on a common image plane during a first frame period by applying first reset signals to the pixel array to reset rows of pixels of the pixel array, exposing the rows of pixels of the pixel array to structured light to cause first analog signals from the rows of pixels, and converting the first analog signals from the rows of pixels of the pixel array into first digital outputs for the structured-light image using one or more analog-to-digital converters at the first dynamic range; and

capture, by the pixel array, a regular image formed on the common image plane during a second frame period longer than the first frame period by applying second reset signals to the pixel array to reset the rows of pixels of the pixel array, exposing the rows of pixels to non-structured light to cause second analog signals from the rows of pixels, and converting the second analog signals from the rows of pixels into second digital outputs for the regular image using said one or more analog-to-digital converters at the second dynamic range; and

wherein the structured-light image is captured before or after the regular image to derive depth or shape information for the regular image.

2. The integrated image sensor of claim 1, wherein said one or more analog-to-digital converters correspond to a configurable analog-to-digital converter to provide both the first dynamic range and the second dynamic range.

3. The integrated image sensor of claim 1, wherein said one or more analog-to-digital converters correspond to two analog-to-digital converters with two different resolutions to provide both the first dynamic range and the second dynamic range.

4. The integrated image sensor of claim 1, wherein said one or more timing and control circuits are further arranged to cause the structured-light image to be captured at lower spatial resolution than the regular image.