Rambus Inc.

Michael Guidash

Thomas Vogelsang

Jay Endsley

Craig M Smith

James Edward Harris

John W Ladd

Alexander Caldwell Schneider

Michael T Ching

Song Xue

Frank Armstrong

Maxim W Smirnov

Signals representative of total photocharge integrated within respective image-sensor pixels are read out of the pixels after a first exposure interval that constitutes a first fraction of a frame interval. Signals in excess of a threshold level are read out of the pixels after an ensuing second exposure interval that constitutes a second fraction of the frame interval, leaving residual photocharge within the pixels. After a third exposure interval that constitutes a third fraction of the frame interval, signals representative of a combination of at least the residual photocharge and photocharge integrated within the pixels during the third exposure interval are read out of the pixels.

Fractional-readout oversampled image sensor

A control pulse is generated a first control signal line coupled to a transfer gate of a pixel to enable photocharge accumulated within a photosensitive element of the pixel to be transferred to a floating diffusion node, the first control signal line having a capacitive coupling to the floating diffusion node. A feedthrough compensation pulse is generated on a second signal line of the pixel array that also has a capacitive coupling to the floating diffusion node. The feedthrough compensation pulse is generated with a pulse polarity opposite the pulse polarity of the control pulse and is timed to coincide with the control pulse such that capacitive feedthrough of the control pulse to the floating diffusion node is reduced.

Feedthrough-compensated image sensor

A pixel array within an integrated-circuit image sensor is exposed to light representative of a scene during a first frame interval and then oversampled a first number of times within the first frame interval to generate a corresponding first number of frames of image data from which a first output image may be constructed. One or more of the first number of frames of image data are evaluated to determine whether a range of luminances in the scene warrants adjustment of an oversampling factor from the first number to a second number, if so, the oversampling factor is adjusted such that the pixel array is oversampled the second number of times within a second frame interval to generate a corresponding second number of frames of image data from which a second output image may be constructed.

High dynamic-range image sensor

A sequence of control voltage levels are applied to a control signal line capacitively coupled to a floating diffusion node of a pixel to sequentially adjust a voltage level of the floating diffusion node. A pixel output signal representative of the voltage level of the floating diffusion node is compared with a reference voltage to identify a first control voltage level of the sequence of control voltage levels for which the voltage level of the floating diffusion node exceeds the reference voltage.

Low-noise, high dynamic-range image sensor

An image sensor architecture with multi-bit sampling is implemented within an image sensor system. A pixel signal produced in response to light incident upon a photosensitive element is converted to a multiple-bit digital value representative of the pixel signal. If the pixel signal exceeds a sampling threshold, the photosensitive element is reset. During an image capture period, digital values associated with pixel signals that exceed a sampling threshold are accumulated into image data.

Conditional-reset, multi-bit read-out image sensor

A pixel circuit within an integrated-circuit image sensor includes a photodiode having a pinning layer of a first conductivity type, a floating diffusion node and a transfer gate disposed between the photodiode and the floating diffusion node. A first control input is coupled to the transfer gate, and a second control input is coupled to the pinning layer of the photodiode to enable the depletion potential of the photodiode to be raised and lowered.

Image sensor with depletion-level pixel charge transfer control

Photocharge is accumulated within an image sensor pixel array during a first exposure interval. At conclusion of the first exposure interval, accumulated photocharge is discarded from a first subset of the pixels to emulate absence of incident light with respect to those pixels. After discarding accumulated photocharge from the first subset of the pixels, first and second readout signals are generated, the first readout signals corresponding to respective pixels not included in the first subset and indicative of photocharge accumulated therein, and the second readout signals corresponding to respective pixels included in the first subset.

Dark-emulation image sensor

A pixel in an integrated-circuit image sensor is enabled to output, throughout a sampling interval, an analog signal having an amplitude dependent, at least in part, on photocharge integrated within a photosensitive element of the pixel. A plurality of samples of the analog signal are generated during an initial portion of the sampling interval that is shorter than a settling time for a maximum possible level of the analog signal.

Image sensor with oversampled column output

In a pixel array within an integrated-circuit image sensor, each of a plurality of pixels is evaluated to determine whether charge integrated within the pixel in response to incident light exceeds a first threshold. N-bit digital samples corresponding to the charge integrated within at least a subset of the plurality of pixels are generated, and then applied to a lookup table to retrieve respective M-bit digital values (M being less than N), wherein a stepwise range of charge integration levels represented by possible states of the M-bit digital values extends upward from a starting charge integration level that is determined based on the first threshold.

Oversampled image sensor with conditional pixel readout

In a pixel array within an integrated-circuit image sensor, a pixel () includes a photodetector () and floating diffusion () formed within a substrate. First () and second () gate elements are disposed adjacent one another over a region () of the substrate between the photodetector and the floating diffusion and coupled respectively to a row line (TGr) that extends in a row direction within the pixel array and a column line (TGc) that extends in a column direction within the pixel array.

Split-gate conditional-reset image sensor

Multiple image data subframes corresponding to respective portions of an exposure interval are generated within a sensor device of an image system. Depending on whether the exposure interval exceeds one or more exposure time thresholds, data representative multiple image data subframes are output from the image sensor device in one of at least two formats, including a first format in which each of the subframes of image data is output in its entirety, and a second format in which a logical combination of at least two of the subframes of image data is output instead of the at least two of the subframes of image data such that the total volume of image data output from the image sensor device is reduced relative to the first format.

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Rochester, NY, United States of America

Michael Guidash