CAPTURING AND PROCESSING OF IMAGES USING MONOLITHIC CAMERA ARRAY WITH HETEROGENEOUS IMAGERS

• US 20110122308A1
• Filed: 11/22/2010
• Published: 05/26/2011
• Est. Priority Date: 11/20/2009
• Status: Active Grant

• Current Assignee: FotoNation Limited (Adeia Inc.)
• Original Assignee: Pelican Imaging Corporation
• Inventors: Duparre, Jacques
• Granted Patent: US 8,514,491 B2
• Time in Patent Office: Days
• US Class Current: 348/340
• CPC Class Codes: G02B 13/001 Miniaturised objectives for electronic devices, e.g. portable telephones, webcams, PDAs, small digital cameras G02B23/243 takes precedence
• 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 5/201 in the form of arrays
• CPC Class Codes: H01L 27/14621 Colour filter arrangements
• CPC Class Codes: H01L 27/14625 Optical elements or arrangements associated with the device
• CPC Class Codes: H04N 23/10 for generating image signals from different wavelengths
• 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 23/51 Housings
• CPC Class Codes: H04N 23/54 Mounting of pick-up tubes, electronic image sensors, deviation or focusing coils
• 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 25/41 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 25/76 Addressed sensors, e.g. MOS or CMOS sensors

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. Lens stack arrays in accordance with many embodiments of the invention include lens elements formed on substrates separated by spacers, where the lens elements, substrates and spacers are configured to form a plurality of optical channels, at least one aperture located within each optical channel, at least one spectral filter located within each optical channel, where each spectral filter is configured to pass a specific spectral band of light, and light blocking materials located within the lens stack array to optically isolate the optical channels.

Claims

1. A lens stack array, comprising:

lens elements formed on substrates separated by spacers, where the lens elements, substrates and spacers are configured to form a plurality of optical channels;

at least one aperture located within each optical channel;

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

light blocking materials located within the lens stack array to optically isolate the optical channels.

2. The lens stack array of claim 1, wherein the light blocking materials are selected from the group consisting of opaque materials, reflective materials and combinations thereof.

3. The lens stack array of claim 1, wherein:

spectral filters that pass different spectral bands are provided within at least two of the imagers.

4. The lens stack array of claim 3, wherein each spectral filter is selected from the group consisting of an organic color filter, an absorptive material, a dielectric coating, an interference filter, a multilayer coating, and combinations thereof.

5. The lens stack array of claim 3, further comprising at least one polarizing filter located within each optical channel.

6. The lens stack array of claim 3, wherein the construction of each optical channel differs based upon the specific spectral band of light passed by the spectral filter within the imager so that chromatic aberrations are reduced.

7. The lens stack array of claim 3, wherein the prescription of at least one surface of a lens within each optical channel is a function of the specific spectral band of light passed by the spectral filter within the optical channel.

8. The lens stack array of claim 7, wherein the back focal lengths of each optical channel in the lens stack array are the same irrespective of the spectral band of light passed by the spectral filter within the optical channel.

9. The lens stack array of claim 3, wherein a combination of high and low Abbe number materials is used in the construction of each of the lens elements in an optical channel to reduce chromatic aberrations.

10. The lens stack array of claim 3, further comprising:

at least one aperture stop located within each optical channel;

wherein each spectral filter is located within each optical channel so that the spectral filter is proximate the aperture stop.

11. The lens stack array of claim 10, wherein each aperture stop is formed by a light blocking material selected from the group consisting of metal materials, oxide materials, black particle filled photoresists and combinations thereof.

12. The lens stack array of claim 3, wherein:

the at least one lens surface of a lens in each optical channel differs based upon the specific spectral band of light passed by the spectral filter within the optical channel; and

each lens surface is selected from the group consisting of diffractive, Fresnel, refractive and combinations thereof.

13. The lens stack array of claim 12, 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 optical channel.

14. The lens stack array of claim 12, wherein each of the optical channels have the same back focal length.

15. The lens stack array of claim 1, wherein at least one of the lens elements in an optical channel is a negative lens element, and the negative lens element is proximate the image formed by the optical channel.

16. The lens stack array of claim 1, wherein at least two of the optical channels have different focal lengths.

17. The lens stack array of claim 1, further comprising a mechanical zoom mechanism within an optical channel configured to smoothly transition between different fields of view.

18. The lens stack array of claim 1, wherein the lens stack array comprises an N×

M array of optical channels, where at least one of N and M is greater than 2.

19. The lens stack array of claim 1, wherein the lens stack array is fabricated using techniques consisting of wafer level optics techniques, injection molding, glass molding and combinations thereof.

20. The lens stack array of claim 1, wherein the light blocking materials located within the lens stack array to optically separate the optical channels comprise at least two opaque surfaces located on a substrate within an optical channel, where the two opaque surfaces have openings arranged in axial alignment with the optical channel.

21. The lens stack array of claim 1, wherein the light blocking materials located within the lens stack array to optically separate the optical channels comprise opaque walls disposed at the boundaries between the optical channels.

22. The lens stack array of claim 21, wherein the opaque walls are cavities between the optical channels filled with light blocking material.

23. The lens stack array of claim 1, wherein a plurality of the spacers are constructed from light blocking materials and are located within the lens stack array to optically separate the optical channels.

24. The lens stack array of claim 1, wherein a plurality of the spacers are coated in light blocking materials and are located within the lens stack array to optically isolate the optical channels.