Camera Arrays Incorporating 3 x 3 Imager Configurations

• US 20140354843A1
• Filed: 08/13/2014
• Published: 12/04/2014
• Est. Priority Date: 05/20/2008
• Status: Active Grant

• Current Assignee: FotoNation Limited (Adeia Inc.)
• Original Assignee: Pelican Imaging Corporation
• Inventors: Venkataraman, Kartik, Jabbi, Amandeep S., Mullis, Robert H., Duparre, Jacques, Hu, Shane Ching-Feng
• Granted Patent: US 9,049,411 B2
• Time in Patent Office: Days
• US Class Current: 348/218.1
• CPC Class Codes: G02B 13/0015 characterised by the lens design
• CPC Class Codes: G02B 3/0056 arranged along two different directions in a plane, e.g. honeycomb arrangement of lenses G02B3/0043 takes precedence; miniaturised objectives for electronic devices employing wafer level optics G02B13/0085
• CPC Class Codes: G02B 3/0062 Stacked lens arrays, i.e. refractive surfaces arranged in at least two planes, without structurally separate optical elements in-between
• CPC Class Codes: G02B 5/20 Filters polarising elements G02B5/30
• CPC Class Codes: G02B 5/201 in the form of arrays
• CPC Class Codes: G06T 11/60 Editing figures and text; Combining figures or text
• CPC Class Codes: G06T 19/20 Editing of 3D images, e.g. changing shapes or colours, aligning objects or positioning parts
• CPC Class Codes: G06T 2200/04 involving 3D image data
• CPC Class Codes: G06T 2207/10028 Range image; Depth image; 3D point clouds
• CPC Class Codes: G06T 2207/10052 Images from lightfield camera
• CPC Class Codes: G06T 2207/20221 Image fusion; Image merging
• CPC Class Codes: G06T 7/50 Depth or shape recovery
• CPC Class Codes: G06T 7/557 from light fields, e.g. from plenoptic cameras
• CPC Class Codes: H04N 13/128 Adjusting depth or disparity
• CPC Class Codes: H04N 13/239 using two 2D image sensors having a relative position equal to or related to the interocular distance H04N13/243 takes precedence
• CPC Class Codes: H04N 13/257 Colour aspects
• CPC Class Codes: H04N 2013/0081 Depth or disparity estimation from stereoscopic image signals
• CPC Class Codes: H04N 23/11 for generating image signals from visible and infrared light wavelengths
• CPC Class Codes: H04N 23/13 with multiple sensors
• CPC Class Codes: H04N 23/16 Optical arrangements associated therewith, e.g. for beam-splitting or for colour correction
• CPC Class Codes: H04N 23/45 : for generating image signals from two or more image sensors being of different type or operating in different modes, e.g. with a CMOS sensor for moving images in combination with a charge-coupled device [CCD] for still images
• CPC Class Codes: H04N 23/54 : Mounting of pick-up tubes, electronic image sensors, deviation or focusing coils
• CPC Class Codes: H04N 23/55 : Optical parts specially adapted for electronic image sensors; Mounting thereof
• CPC Class Codes: H04N 23/60 : Control of cameras or camera modules
• CPC Class Codes: H04N 23/69 : Control of means for changing angle of the field of view, e.g. optical zoom objectives or electronic zooming
• CPC Class Codes: H04N 23/698 : for achieving an enlarged field of view, e.g. panoramic image capture
• CPC Class Codes: H04N 23/88 : for colour balance, e.g. white-balance circuits or colour temperature control
• CPC Class Codes: H04N 23/90 : Arrangement of cameras or camera modules, e.g. multiple cameras in TV studios or sports stadiums
• CPC Class Codes: H04N 23/951 : by using two or more images to influence resolution, frame rate or aspect ratio
• CPC Class Codes: H04N 25/131 : including elements passing infrared wavelengths
• CPC Class Codes: H04N 25/133 : including elements passing panchromatic light, e.g. filters passing white light
• CPC Class Codes: H04N 25/135 : based on four or more different wavelength filter elements
• CPC Class Codes: H04N 25/41 : Extracting pixel data from a plurality of image sensors simultaneously picking up an image, e.g. for increasing the field of view by combining the outputs of a plurality of sensors
• CPC Class Codes: H04N 25/48 : Increasing resolution by shifting the sensor relative to the scene
• CPC Class Codes: H04N 25/581 : acquired simultaneously
• CPC Class Codes: H04N 25/60 : Noise processing, e.g. detecting, correcting, reducing or removing noise
• CPC Class Codes: H04N 25/67 : applied to fixed-pattern noise, e.g. non-uniformity of response
• CPC Class Codes: H04N 25/705 : Pixels for depth measurement, e.g. RGBZ
• CPC Class Codes: H04N 25/79 : Arrangements of circuitry being divided between different or multiple substrates, chips or circuit boards, e.g. stacked image sensors
• CPC Class Codes: H04N 5/262 : Studio circuits, e.g. for mixing, switching-over, change of character of image, other special effects ; Cameras specially adapted for the electronic generation of special effects
• CPC Class Codes: H04N 5/265 : Mixing

Abstract

Systems and methods for implementing array cameras configured to perform super-resolution processing to generate higher resolution super-resolved images using a plurality of captured images and lens stack arrays that can be utilized in array cameras are disclosed. An imaging device in accordance with one embodiment of the invention includes at least one imager array, and each imager in the array comprises a plurality of light sensing elements and a lens stack including at least one lens surface, where the lens stack is configured to form an image on the light sensing elements, control circuitry configured to capture images formed on the light sensing elements of each of the imagers, and a super-resolution processing module configured to generate at least one higher resolution super-resolved image using a plurality of the captured images.

Claims

1. A camera array, comprising:

a plurality of imagers, where each imager comprises;

optics comprising at least one lens element and at least one aperture that form an optical channel; and

a sensor comprising a two dimensional array of pixels and control circuitry for controlling imaging parameters; and

at least one spectral filter located within the imager, where each spectral filter is configured to pass a specific spectral band of light;

wherein the plurality of imagers are configured to capture different images of the same scene;

wherein the plurality of imagers forms at least a 3×

3 configuration of imagers comprising;

an imager having a green filter at the center of a 3×

3 configuration of imagers;

two imagers having red filters located on opposite sides of the 3×

3 configuration of imagers;

two imagers having blue filters located on opposite sides of the 3×

3 configuration of imagers; and

four imagers having green filters surrounding the central imager having a green filter; and

wherein the shape of at least one lens element of the imagers having green filters differs from the shape of at least one lens element of the imagers having red filters and the imagers having blue filters.

2. The camera array of claim 1, wherein:

the images captured by the plurality of imagers include different occlusions sets, where the occlusion set of a given imager is the portion of a scene visible to the central imager in the plurality of imagers that is occluded from the view of the given imager; and

the camera array further comprises an image processing pipeline module configured to produce an image by reconstructing color information around an edge of a foreground object that is visible to the central imager and is in the occlusion set of at least one of the plurality of imagers using pixels captured around the edge of the foreground object by at least one of the imagers in the 3×

3 configuration of imagers.

3. The camera array of claim 1, wherein the camera array comprises a 3×

3 array of imagers.

4. The camera array of claim 1, wherein the imager array comprises a 4×

4 array of imagers.

5. The camera array of claim 1, wherein the imager array comprises a 5×

5 array of imagers.

6. The camera array of claim 1, wherein the prescription of at least one surface of a lens in an imager is a function of the specific spectral band of light passed by the spectral filter within the imager.

7. The camera array of claim 1, wherein the radii of curvature of the lens surfaces differ based upon the specific spectral band of light passed by the spectral filter within the imager.

8. The camera array of claim 1, wherein the control circuitry of the imagers including different types of filters configures the imagers to operate with at least one difference in operating parameters.

9. The camera array of claim 8, wherein the at least one difference in operating parameters includes at least one imaging parameter selected from the group consisting of exposure time, gain, and black level offset.

10. The camera array of claim 1, wherein the camera array is a monolithic camera array assembly comprising:

a lens stack array comprising an array of optical channels that form the optics of each imager; and

a single semiconductor substrate on which all of the pixels and control circuitry for each imager are formed.

11. The camera array of claim 1, wherein the plurality of imagers are formed on separate semiconductor substrates.

12. The camera array of claim 1, wherein the camera array further comprises an image processing pipeline module configured to estimate distance to an object in images captured by the plurality of imagers.

13. The camera array of claim 1, wherein the image processing pipeline module is further configured to generate a depth map using images captured by the plurality of imagers.

14. The camera array of claim 12, wherein the image processing pipeline module is configured to select at least one distance as an “

in best focus”

distance and blur an image produced by the camera array based upon estimated distance information.

15. The camera array of claim 14, wherein the image processing pipeline module is configured to utilize the depth map to guide the level of blur applied to the pixels of the image produced by the camera array.

16. The camera array of claim 1, wherein:

the different images of the same scene captured by the plurality of imagers include non-redundant information;

the camera array further comprises an image processing pipeline module configured to generate at least one higher resolution super-resolved image using the different images of the same scene; and

the image processing pipeline module is further configured to perform parallax detection to generate parallax information to align portions of the different images of the same scene.

17. The camera array of claim 16, wherein the parallax information includes a depth map.

18. The camera array of claim 17, wherein the image processing pipeline module is configured to select at least one distance as a focal plane and to apply blurring to pixels in at least one higher resolution super-resolved image with depths in the depth map that are not proximate a focal plane

19. A camera array assembly, comprising:

a monolithic integrated module forming a plurality of imagers, where each imager comprises;

a lens stack array comprising an array of optical channels that form the optics of each imager, where each optical channel comprises at least one lens element and at least one aperture forming a lens stack; and

a single semiconductor substrate on which all of the pixels and control circuitry for each imager are formed; and

at least one spectral filter located within each imager, where each spectral filter is configured to pass a specific spectral band of light; and

an image processing pipeline module configured to estimate distance to an object in a scene using images captured by the plurality of imagers;

wherein the plurality of imagers are configured to capture different images of the same scene;

wherein the plurality of imagers forms at least a 3×

3 configuration of imagers comprising;

an imager having a green filter at the center of a 3×

3 configuration of imagers;

two imagers having red filters located on opposite sides of the 3×

3 configuration of imagers;

two imagers having blue filters located on opposite sides of the 3×

3 configuration of imagers; and

four imagers having green filters surrounding the central imager having a green filter; and

wherein the shape of at least one lens element of the imagers having green filters differs from the shape of at least one lens element of the imagers having red filters and the imagers having blue filters.

20. A camera array, comprising:

a plurality of imagers formed on separate semiconductor substrates, where each imager comprises;

optics comprising at least one lens element and at least one aperture that form an optical channel; and

a sensor comprising a two dimensional array of pixels and control circuitry for controlling imaging parameters; and

at least one spectral filter located within the imager, where each spectral filter is configured to pass a specific spectral band of light; and

an image processing pipeline module configured to estimate distance to an object in a scene using images captured by the plurality of imagers;

wherein the plurality of imagers are configured to capture different images of the same scene;

wherein the plurality of imagers forms at least a 3×

3 configuration of imagers comprising;

an imager having a green filter at the center of a 3×

3 configuration of imagers;

two imagers having red filters located on opposite sides of the 3×

3 configuration of imagers;

two imagers having blue filters located on opposite sides of the 3×

3 configuration of imagers; and

four imagers having green filters surrounding the central imager having a green filter;

wherein the shape of at least one lens element of the imagers having green filters differs from the shape of at least one lens element of the imagers having red filters and the imagers having blue filters.