Array Cameras Incorporating Monolithic Array Camera Modules with High MTF Lens Stacks for Capture of Images used in Super-Resolution Processing

摘要

A variety of optical arrangements and methods of modifying or enhancing the optical characteristics and functionality of these optical arrangements are provided. The optical arrangements being specifically designed to operate with camera arrays that incorporate an imaging device that is formed of a plurality of imagers that each include a plurality of pixels. The plurality of imagers include a first imager having a first imaging characteristics and a second imager having a second imaging characteristics. The images generated by the plurality of imagers are processed to obtain an enhanced image compared to images captured by the imagers. In many optical arrangements the MTF characteristics of the optics allow for contrast at spatial frequencies that are at least as great as the desired resolution of the high resolution images synthesized by the array camera, and significantly greater than the Nyquist frequency of the pixel pitch of the pixels on the focal plane, which in some cases may be 1.5, 2 or 3 times the Nyquist frequency.

主权项

1. An array camera, comprising:
a camera array, where the camera array is a monolithic integrated module comprising:
a single semiconductor substrate on which light sensing elements for a plurality of focal planes are formed, where the light sensing elements of a given focal plane from the plurality of focal planes have a pixel pitch defining a Nyquist frequency;optics including a plurality of lens elements forming a plurality of lens stacks, where each lens stack in the plurality of lens stacks:
forms an image on one of the plurality of focal planes;has a field of view that is shifted with respect to the field-of-views of the other lens stacks and so that each shift includes a sub-pixel shifted view of the scene; andhas a modular transfer function (MTF) such that the lens stack optically resolves contrast at spatial frequencies larger than the Nyquist frequency (Ny); andcontrol circuitry that coordinates the independent capture of low resolution images of a scene by the focal planes; and a processor; wherein software directs the processor to:
obtain a set of low resolution images from the camera array, where each of the low resolution images include aliasing patterns, where each of the low resolution images includes different aliasing patterns due to the different sub-pixel shifted views of the scene provided by the lens stacks;determine disparity between pixels in the set of low resolution images to generate a depth map from a reference viewpoint, where the depth map indicates distances to surfaces of scene objects from the reference viewpoint;synthesizing a high resolution image using the set of images and the depth map, where the spatial frequency at which the high resolution image displays contrast is greater than the Nyquist frequencies (Ny) of the plurality of focal planes and less than the spatial frequencies at which the plurality of lens stacks optically resolve contrast.