82results about How to "Reduce pattern noise" patented technology

A method for controlling the exposure of an active pixel array electronic still camera includes the steps of: integrating photocurrent in each pixel during an integration time period; collecting overflow charge from all pixels in the array during the integration time period; developing an overflow signal as a function of the overflow charge; and terminating the integration time period when the overflow signal exceeds a preset threshold level selected to represent a desired reference exposure level. Apparatus for performing the method of the present invention includes circuitry for integrating photocurrent in each pixel during a integration time period; circuitry for diverting and detecting overflow charge from all pixels in the array during the integration time period; circuitry for developing an overflow signal as a function of the overflow charge; and circuitry for terminating said integration time period when the overflow signal exceeds a preset threshold level selected to represent a desired reference exposure level.

An image sensor and method, which includes a switching device for establishing a connection between at least one column line and one of at least two analog-to-digital converter blocks, where at least one of the at least two analog-to-digital converter blocks is connectable to at least two rows of a plurality of unit pixels. An image sensor and method, where, if a row line is odd, column outputs from odd column lines of an active pixel sensor array are connected to a first correlated double sampling block and column outputs from even column lines of the active pixel sensor array are connected to a second correlated double sampling block and if the row line is even, column outputs from odd column lines of the active pixel sensor array are connected to the second correlated double sampling block and column outputs from even column lines of the active pixel sensor array are connected to the first correlated double sampling block. An image sensor and method where a first subset of a plurality of unit pixels are connected to a first correlated double sampling block and a second subset of the plurality of unit pixels are connected to a second correlated double sampling block, where the first subset of the plurality of unit pixels are blue and red pixels and the second subset of the plurality of unit pixels are green pixels. A circuit and method for reducing fixed pattern noise.

This invention is directed to imaging methods and systems for flexibly addressing and processing imaging pixel sensor elements. A novel architecture is described which allows for a highly integrated, low cost imager with high speed performance and good image quality. The imaging system provides on-the-fly color interpolation, color compensation (also called color correction, color maximization or white balance) and / or fixed pattern noise reduction. The hardware and / or software related to on-the-fly color interpolation, color compensation and / or fixed pattern noise reduction may be provided on-chip.

An image sensing apparatus comprises a transfer block including a first transfer unit and a second transfer unit, wherein the first transfer unit includes a first impedance converter which transfers a first signal to the output unit, and the first transfer unit transfers, as a third signal, a difference signal between a first offset of the first impedance converter and a signal obtained by superimposing the first offset on the first signal, the second transfer unit includes a second impedance converter which transfers a second signal to the output unit, and the second transfer unit transfers, as a fourth signal, a difference signal between a second offset of the second impedance converter and a signal obtained by superimposing the second offset on the second signal, and the output unit calculates a difference between the third signal and the fourth signal, generating and outputting an image signal.

A pixel includes a photo-sensitive element for generating charges in response to incident radiation. A transfer gate is positioned between the photo-sensitive element and a sense node for controlling transfer of charges to the sense node. A reset switch is connected to the sense node for resetting the sense node to a predetermined voltage. A first buffer amplifier has an input connected to the sense node and an output connected to a sample stage operable to sample a value of the sense node. A second buffer amplifier has an input connected to the sample stage. Control circuitry operates the reset switch and causes the sample stage to sample the sense node while the photo-sensitive element is exposed to radiation. An array of pixels is synchronously exposed to radiation. Sampled values for a first exposure period can be read while the photo-sensitive element is exposed for a second exposure period.

A backside illuminated imaging device performs imaging by illuminating light from a back side of a p substrate to generate electric charges in the substrate based on the light and reading out the electric charges from a front side of the substrate. The device includes n layers located in the substrate and on an identical plane near a front side surface of the substrate and accumulating the electric charges; n+ layers between the respective n layers and the front side of the substrate, the n+ layers having an exposed surface exposed on the front side surface of the substrate and functioning as overflow drains for discharging unnecessary electric charges accumulated in the n layers; p+ layers between the respective n+ layers and the n layers and functioning as overflow barriers of the overflow drains; and an electrode connected to the exposed surface of each of the n+ layers.

The present invention discloses an apparatus of high dynamic-range CMOS image sensor and method thereof. The present invention utilize a pixel circuit outputting an output signal, wherein the pixel circuit has a photodiode and a plurality of transistors; and utilize a current source as a charge supplement unit to supply current into one end of the photodiode, and providing charges to the parasitic capacitor of the photodiode to delay saturation in the pixel circuit. In addition, a feedback circuit can be further designed connecting the pixel circuit. The feedback circuit receives the output signal from the pixel circuit and then outputs a control signal according to the output signal of the pixel circuit to control status of the charge supplement unit, and thereby increasing the dynamic range of the CMOS image sensor.