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Characterization of quanta image sensor pixels with deep sub-electron read noise is reported. Pixels with conversion gain of $423\mu \text{V}$ /e- and read noise as low as 0.22e- r.m.s. were measured. Dark current is 0.1e-/s at room temperature, and lag less than 0.1e-. This is one of the first works reporting detailed characterization of image sensor pixels with mean signals from sub-electron (0.25e-) to a few electrons level. Such pixels in a nearly-conventional CMOS image sensor process will allow realization of photon-counting image sensors for a variety of applications.

Superresolution from plenoptic cameras or camera arrays is usually treated similarly to superresolution from video streams. However, the transformation between the low-resolution views can be determined precisely from camera geometry and parallax. Furthermore, as each low-resolution image originates from a unique physical camera, its sampling properties can also be unique. We exploit this option with a custom design of either the optics or the sensor pixels. This design makes sure that the sampling matrix of the complete system is always well-formed, enabling robust and high-resolution image reconstruction. We show that simply changing the pixel aspect ratio from square to anamorphic is sufficient to achieve that goal, as long as each camera has a unique aspect ratio. We support this claim with theoretical analysis and image reconstruction of real images. We derive the optimal aspect ratios for sets of 2 or 4 cameras. Finally, we verify our solution with a camera system using an anamorphic lens.

We present a CMOS image sensor that enables a compact 3-dimensional (3D) vision camera system comprising a single set of the sensor and a camera lens. In order to make binocular parallax, which is essential for 3D imaging, the input pupil of the camera lens is presumed to consist of the right-eye and the left-eye domains, where the pixels exclusively receiving light beams from the right-eye domain and those from the left-eye domain, are arranged alternately. In addition, the sensor features an on-chip lenticular lens to split the incident light from the two directions and a Digital Micro Lens [1,2] to focus the split light beams onto the dedicated pixels without significant crosstalk. The fabricated 3D image sensor enables not only successful stereovision imaging in color with sufficiently high sensitivity, but also accurate calculation of distance.

Image sensors for digital cameras are built with ever decreasing pixel sizes. The size of the pixels seems to be limited by technology only. However, there is also a hard theoretical limit for classical video camera systems: During a certain exposure time only a certain number of photons will reach the sensor. The resulting shot noise thus limits the signal-to-noise ratio. In this letter we show that current sensors are already surprisingly close to this limit.