Large field of view multi-camera endoscopic apparatus with omni-directional illumination

Patent metadata

Field	Value
Publication number	US-10334163-B2
Application number	US-201515120527-A
Country	US
Kind code	B2
Filing date	Feb 24, 2015
Priority date	Feb 26, 2014
Publication date	Jun 25, 2019
Grant date	Jun 25, 2019

Abstract

A multi-camera hemispherical very wide field of view imaging apparatus with omnidirectional illumination capability comprises a cylindrical body ( 4, 4. a, 4. b ), a hemispherical mechanical frame ( 2 ) arranged on one end of the cylindrical body ( 4, 4. a, 4. b ), a plurality of imaging channels ( 3 ), each imaging channel ( 3 ) comprising at least an image sensor and related optics with a fixed focus appropriate for endoscopic imaging, the plurality of imaging channels ( 3 ) being distributed over the hemispherical mechanical frame ( 2 ), a light source arranged center-down at a back part of the plurality of imaging channels ( 3 ) and inside or at the end of the cylindrical body ( 4, 4. a, 4. b ). Each imaging channel ( 3 ) comprises a plurality of lightning channels ( 1 ) around their center, each of the plurality of lightning channels ( 1 ) comprising at least one microfiber light guide having a determined angle of curvature arranged to transmit the light from the light source. The imaging apparatus further comprises a control and processing circuit ( 5 ) comprising a camera control unit ( 6 ), an illumination control unit ( 7 ), an illumination unit ( 8 ), a sample and capture unit ( 9 ), an image processing unit ( 10 ) and an output interface ( 11 ) to a PC. The camera control unit ( 6 ) is configured to power each of the plurality of imaging channels ( 3 ) and make automatic gain compensation for each imaging channel ( 3 ), the illumination control unit ( 7 ) is configured for automatic intensity dimming, the sample and capture unit ( 9 ) is an interface circuit for correct sampling, extraction and capturing frames of individual imaging channels ( 3 ), the image processing unit ( 10 ) is configured for constructing a spherical panoramic image by applying a determined algorithm, and the output interface ( 11 ) is arranged to output the spherical panoramic image to a system configured to visualize it.

First claim

The invention claimed is:

1. A multi-camera hemispherical very wide field of view imaging apparatus with omnidirectional illumination capability, the apparatus comprising:
a body;
a hemispherical mechanical frame arranged on an end of the body;
a plurality of imaging channels, each imaging channel including an image sensor and optics with a fixed focus for endoscopic imaging, the plurality of imaging channels being distributed over the hemispherical mechanical frame such that each imaging channel has a different viewing direction;
a central light source configured to provide light to the plurality of imaging channels; and
a control and processing circuit including a camera control unit, an illumination control unit, a sample and capture unit, and an image processing unit,
wherein each imaging channel includes a plurality of fiber optical illumination channels around a center of the respective imaging channel, each of the plurality of fiber optical illumination channels including a microfiber light guide having a determined angle of curvature arranged to transmit light from the central light source to an area outside of the hemispherical mechanical frame, and
wherein the camera control unit is configured to perform automatic gain compensation for each of the plurality of imaging channels, the illumination control unit is configured to perform automatic intensity dimming for each of the plurality of imaging channels, the sample and capture unit having an interface circuit for sampling, extraction and capturing frames of individual imaging channels, and the image processing unit is configured generate a spherical panoramic image by applying an algorithm.

2. The multi-camera apparatus of claim 1 , wherein the control and processing circuit further includes an output interface, the output interface is configured to output the spherical panoramic image to a system, the system configured to visualize the spherical panoramic image.

3. The multi-camera apparatus of claim 1 , wherein the body is cylindrical.

4. The multi-camera apparatus of claim 1 , wherein the central light source is arranged center-down at a back part of the plurality of imaging channels and inside or at the end of the body.

5. The multi-camera apparatus of claim 1 , wherein for each fiber optical illumination channel that is associated with the respective imaging channel, a light exit face of the microfiber light guide is arranged at a side of a respective opening for the imaging channel on the hemispherical mechanical frame.

6. The multi-camera apparatus of claim 1 , wherein each imaging channel includes at least four fiber optical illumination channels, a light exit face of the microfiber light guide of the at least four fiber optical illumination channels arranged at a middle of a side of a respective opening for the imaging channel on the hemispherical mechanical frame.

7. The multi-camera apparatus of claim 1 , wherein light exit faces of the microfiber light guide of the plurality of fiber optical illumination channels are arranged in rows between adjacent imaging channels.

8. The multi-camera apparatus of claim 7 , wherein the rows are arranged to surround each opening for the plurality of imaging channels on the hemispherical mechanical frame.

9. The multi-camera apparatus of claim 1 , wherein light exit faces of the microfiber light guide of the plurality of fiber optical illumination channels are arranged at a spherical surface of the hemispherical mechanical frame.

10. The multi-camera apparatus of claim 1 , wherein each light exit face of the microfiber light guide of the plurality of fiber optical illumination channels are arranged on a spherical surface of the hemispherical mechanical frame.

11. The multi-camera apparatus of claim 1 , wherein a light beam of each microfiber light guide of the plurality of fiber optical illumination channels has a different illumination angle.

Assignees

• Ecole Polytechnique Fed Lausanne Epfl

Inventors

• Cogal Ömer
• Leblebici Yusuf

Classifications

• H04N23/72

  Combination of two or more compensation controls · CPC title

• H04N23/51

  Housings · 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

• H04N23/76

  by influencing the image signals · CPC title

• H04N23/90

  Arrangement of cameras or camera modules, e.g. multiple cameras in TV studios or sports stadiums · CPC title