In vivo camera with multiple sources to illuminate tissue at different distances

Patent metadata

Field	Value
Publication number	US-11103129-B2
Application number	US-201414580092-A
Country	US
Kind code	B2
Filing date	Dec 22, 2014
Priority date	Jun 9, 2008
Publication date	Aug 31, 2021
Grant date	Aug 31, 2021

Abstract

An in vivo endoscope illuminates tissue using multiple sources. Light from a short-range source exits a tubular wall of the endoscope through a first illumination region that overlaps an imaging region, and the light returns through the imaging region after reflection by tissue, to form an image in a camera. Light from a long-range source exits the tubular wall through a second illumination region that does not overlap the imaging region. The endoscope of some embodiments includes a mirror, and light from an emitter for the short-range source is split and reaches the first illumination region from both sides of an optical axis of the camera. Illuminating the first illumination region with split fractions of light results in greater uniformity of illumination, than illuminating directly with an un-split beam. The energy generated by each source is changed depending on distance of the tissue to be imaged.

First claim

What is claimed is:

1. A device comprising:
a camera enclosed within an endoscope housing, the camera comprising a lens, the camera having at least one optical axis intersecting the lens and the endoscope housing;
a plurality of emitters enclosed within the endoscope housing, the plurality of emitters being located around the camera;
wherein electromagnetic radiation is emitted by at least one emitter in the plurality of emitters; and
a reflective surface enclosed within the endoscope housing;
wherein the reflective surface is offset from the at least one optical axis, and the at least one optical axis does not intersect the reflective surface, the reflective surface being located in a path of at least a portion of the electromagnetic radiation so as to reflect the portion out through the endoscope housing;
wherein at least the portion of the electromagnetic radiation passes within the endoscope housing, from the at least one emitter, at least going across the at least one optical axis to the reflective surface;
wherein the camera is positioned within the endoscope housing such that at least a portion of an image is formed in the camera by at least reflected electromagnetic radiation entering the endoscope housing after reflection outside the endoscope housing.

2. The device of claim 1 wherein the plurality of emitters are hereinafter a first plurality of emitters and wherein:
the device further comprises a second plurality of emitters; and
additional electromagnetic radiation emitted by at least one emitter in the second plurality exits the endoscope housing without reflection.

3. The device of claim 1 further comprising:
a concentrator having an axis that passes through a location of the at least one emitter, the concentrator being located between the at least one emitter and the reflective surface;
wherein the concentrator concentrates at least the portion of the electromagnetic radiation.

4. The device of claim 1 wherein the portion of electromagnetic radiation is hereinafter a first portion, and wherein the reflective surface is hereinafter a first reflective surface, the endoscope housing has a near end and a far end, and wherein:
the device further comprises a second reflective surface offset from the optical axis of the camera in a longitudinal direction towards the far end; and
each emitter in the plurality of emitters is offset from the optical axis of the camera in the longitudinal direction towards the far end; and
the second reflective surface is located in a path of a second portion of electromagnetic radiation emitted by the at least one emitter in the plurality of emitters so as to reflect at least the second portion of electromagnetic radiation out through the endoscope housing.

5. The device of claim 1 wherein the endoscope housing has a near and a far end, the endoscope housing comprises a dome at the near end.

6. The device of claim 5 wherein the plurality of emitters are hereinafter a first plurality of emitters, wherein:
the device further comprises a second plurality of emitters;
the second plurality of emitters are offset from the optical axis of the camera toward the near end;
the near end is located opposite to the far end; and
the second plurality of emitters are located between the reflective surface and the dome.

7. The device of claim 4 wherein:
the second reflective surface is comprised in an optical element that has an input aperture facing the at least one emitter and an output aperture at which the second portion of electromagnetic radiation has reduced angular divergence; and
the optical element has an additional input aperture and an additional output aperture such that at least a third portion of electromagnetic radiation emitted by the at least one emitter enters the optical element through the additional input aperture and exits the optical element at the additional output aperture.

8. The device of claim 4 wherein:
the second reflective surface is on one side of a layer; and
the layer has another side that reflects at least an additional portion of electromagnetic radiation emitted by the at least one emitter.

9. The device of claim 1 wherein:
a longitudinal plane passes through a point (hereinafter “intersection point”) formed by intersection of a surface of the endoscope housing with the optical axis of the camera, the longitudinal plane further passes through a center of curvature C of an arc AB, the arc AB being defined by intersection of the surface of the endoscope housing with a lateral plane parallel to the optical axis and passing through the intersection point, the lateral plane and the longitudinal plane being oriented perpendicular to one another; and
the device comprises another reflective surface that limits angular divergence of at least some illumination rays emitted from the at least one emitter such that a projection on to the longitudinal plane, of an illumination ray, after reflection from the intersection point, makes an angle θ i with a normal to the surface of the endoscope housing such that θ i >θ FOV +α wherein θ FOV is half angle of a field of view of the camera projected in the longitudinal plane and α is an angle between the normal and the optical axis.

10. The device of claim 1 wherein:
a first illumination ray emitted by the at least one emitter is incident on the endoscope housing with angle of incidence θ i and is reflected with an identical angle of reflection θ i relative to a line N that bisects an angle formed by the first illumination ray and a reflected ray resulting from reflection of the first illumination ray by the endoscope housing;
a point U exists at the intersection of a first line collinear with the incident ray and a second line collinear with the reflected ray;
a first image forming ray forms an angle σ with line N, the first image forming ray being comprised in a plurality of image forming rays, the plurality of image forming rays forming a cropped portion of the image supplied to a transmitter comprised in the device;
additional illumination rays from the at least one emitter are restricted in angle such that θ i >σ for a majority of pairs of any additional illumination ray incident on the endoscope housing and a corresponding additional image forming ray comprised in the plurality of image forming rays;
the first image forming ray, when located within a free space between the endoscope housing and the camera, is collinear to a line passing through the point U and a pupil of the camera; and
the line is coplanar with the first illumination ray and the reflected ray.

11. The device of claim 1 wherein:
the reflective surface has an annular shape.

12. The device of claim 7 wherein:
the optical element comprises a plurality of spokes between an inner sidewall and an outer sidewall; and
the second reflective surface is between walls of two adjacent radial spokes, on one of the inner sidewall or the outer sidewall.

13. The device of claim 1 wherein the reflective surface is hereinafter a first reflective surface, and wherein:
a second reflective surface is between walls of two spokes that are radial, the radial spokes being located between an inner sidewall and an outer sidewall, the second reflective surface is on one of the inner sidewall or the outer sidewall.

14. The device of claim 12 wherein:
edges of a third reflective surface, the second reflective surface and the walls of the two adjacent spokes define a boundary of an input aperture of the optical element; and
the at least one emitter is located directly facing the input aperture.

15. The device of claim

Assignees

• Capso Vision Inc
• Capsovision Inc

Inventors

• Wilson Gordon C

Classifications

• A61B1/00009

  of image signals during a use of endoscope · CPC title

• A61B1/0607 Primary

  for annular illumination · CPC title

• A61B1/0625 Primary

  for multiple fixed illumination angles · CPC title

• A61B1/0623

  for off-axis illumination · CPC title

• A61B1/00006

  of control signals · CPC title