Semiconductor Components Industries, LLC

Aptina Imaging Corporation

Richard Scott Johnson

Junichi Nakamura

Gennadiy A Agranov

Dongqing Cao

Tomas Geurts

Ross F Jatou

Sandor Lee Barna

Douglas Fettig

Debashree Guruaribam

Ulrich C Boettiger

Richard A Mauritzson

John W Ladd

Manuel H Innocent

Brian W Keelan

Minseok Oh

Christopher D Silsby

Orit Skorka

Pawan Gilhotra

Robert Michael Gravelle, Jr

Kai Shen

A high dynamic range imaging pixel may include a photodiode that generates charge in response to incident light. When the generated charge exceeds a first charge level, the charge may overflow through a first transistor to a first storage capacitor. When the generated charge exceeds a second charge level that is higher than the first charge level, the charge may overflow through a second transistor. The charge that overflows through the second transistor may alternately be coupled to a voltage supply and drained or transferred to a second storage capacitor for subsequent readout. Diverting more overflow charge to the voltage supply may increase the dynamic range of the pixel. The amount of charge diverted to the voltage supply may therefore be updated to control the dynamic range of the imaging pixel.

Image sensors having high dynamic range imaging pixels

A high dynamic range imaging pixel may include first and second photodiodes that generate charge in response to incident light. The second photodiode may have a higher sensitivity than the first photodiode. When generated charge in the first photodiode exceeds a given charge level, the charge may overflow through a transistor to a capacitor. The overflow path from the first photodiode to the capacitor may optionally pass through the floating diffusion region. A transistor may be coupled between the first and second photodiodes. A gain select transistor may be coupled between the floating diffusion region and the capacitor. After sampling the overflow charge, the charge from both the first and second photodiodes may be sampled. In one arrangement, overflow charge may be transferred to a capacitor in a subsequent row.

High dynamic range imaging pixels with multiple photodiodes

An image sensor may include a shared pixel circuit having multiple photodiodes coupled to a common floating diffusion node via respective charge transfer gates. First, the pixel circuit may be reset, and a sample-and-hold reset (SHR) value may be read out. Charge from a first of the photodiodes may be transferred to the floating diffusion node, and a first sample-and-hold signal (SHS) value may be read out. A first correlated double sampling (CDS) value is obtained by computing the difference between the SHR value and the first SHS value. Without resetting again, charge from a second of the photodiodes may be transferred to the floating diffusion node, and a second SHS value may be read out. A second CDS value is obtained by computing the difference between the first and second SHS values. Reading out the shared pixel circuit in this way substantially reduces power consumption.

Low power shared image pixel architecture

An image sensor may include an array of image pixels. Control circuitry coupled to the array of pixels may be configured to operate the image pixels in an overflow mode of operation, in which each pixel generates an overflow image signal and a complete image signal from a single exposure time period. The overflow image signals and the complete image signals from the pixels may be used to generate a high dynamic range image. While the floating diffusion region in each pixel is not in use, control circuitry may control that pixel to generate a reference signal at the floating diffusion region indicative of pixel-specific dark signal noise. Processing circuitry may mitigate for dark signal non-uniformity across the pixels by correcting the complete image signals using the reference signal to remove dark signal noise in the complete image signals.

Imaging systems and methods for reducing dark signal non-uniformity across pixels

An image senor may include an array of pixels controlled by row control circuitry. Each pixel may include a photodiode for generating image signals and a charge storage structure coupled to a floating diffusion region and configured to generate and store parasitic light noise level signals. The image signals and the parasitic light noise level signals may be read out in the same readout cycle using shared or separate readout circuitry. Processing circuitry may selectively process the image signals based on the parasitic light noise level signals to generate image signals with reduced noise.

Image sensors with reduced noise

Various embodiments of the present technology may comprise a method and apparatus for a polarizing filter. The polarizing filter may be formed such that the filter has varying polarization axes for blocking reflected light emitted from various directions. The method and apparatus may utilize metal wires or molecular chains to form curved lines across the filter, where the curved lines define the polarization axes.

Methods and apparatus for a polarizing image sensor

An imaging device may have an array of image sensor pixels. The array of image sensor pixels may have main pixels and reference pixels that are overlapped by optical stacks. The reference pixels may be more resistant to weathering, such as solar degradation, than the main pixels. For example, optical stacks overlapping the main pixels may include antireflection coatings, while optical stacks overlapping the reference pixels may not include antireflection coatings. Alternatively or additionally, the optical stacks overlapping the main pixels may include color filter resist formed from a first pigment, and the optical stacks overlapping the reference pixels may include color filter resist formed from a second pigment that is more resistant to weathering than the first pigment. Processing circuitry may compare outputs of the main pixels and the reference pixels to determine whether pixels in the array have been damaged.

Imaging systems with weathering detection pixels

An image sensor may include an array of imaging pixels. Each imaging pixel may include a first sub-pixel that is configured to generate a high light-sensitivity signal and a second sub-pixel that is configured to generate a low light-sensitivity signal. The image sensor may also include a plurality of dark pixels that are shielded from incident light and processing circuitry. The processing circuitry may be configured to, for each imaging pixel, compare a value based on at least one of the high light-sensitivity signal and the low light-sensitivity signal to a threshold, modify the high light-sensitivity signal for the respective imaging pixel based at least on the low light-sensitivity signal for the respective imaging pixel when the value is less than the threshold, and modify the high light-sensitivity signal for the respective imaging pixel based on at least one dark pixel signal when the value is greater than the threshold.

Image sensors having dark pixels and imaging pixels with different sensitivities

An imaging device may have an array of image sensor pixels and image readout circuitry coupled to the array of image sensor pixels. Predictive pre-charge circuitry may be coupled to the array of image sensor pixels and the image readout circuitry. The predictive pre-charge circuitry and the image readout circuitry may perform correlated double sampling operations during charge readout, comparing the charge generated by the array of image pixels to a known reset value. The predictive pre-charge circuitry may pre-charge output lines from the array of image pixels, thereby reducing the time needed for the circuitry to read out the charge after being reset. The output lines may be pre-charged prior to reading out the charge of a row of image sensor pixels based on a voltage associated with the charge generated by at least one previous row of image sensor pixels of the array of image sensor pixels.

Image sensors with predictive pre-charging circuitry

Various embodiments of the present technology may comprise a method and apparatus for anti-eclipse circuit verification. According to various embodiments, the image sensor is configured to test and/or determine the functionality of the anti-eclipse circuit. In various embodiments, the anti-eclipse circuit may employ redundant circuits and/or devices. In a case where a circuit fault is detected, the image sensor generates an error signal.

Methods and apparatus for anti-eclipse circuit verification

An image sensor may include an array of image pixels formed in rows and columns. Each image pixel in the array may include a photodiode and multiple signal readout paths connected to the photodiode. Each readout path may include a separate floating diffusion node and source follower transistor. The number of signal readout paths simultaneously enabled during an image capture operation may be determined by the exposure level such that the pixel operates with either high or low conversion gain. Several such image pixels of like color in the pixel array may be connected via a shared photodiode interconnection line such that image signals from interconnected pixels may either be binned and read out on a single readout path or read out individual on separate readout paths.

Multi-conversion gain pixel configurations

Various embodiments of the present technology may comprise a method and apparatus for pixel binning and readout. The method and apparatus may determine a region of interest and a region of non-interest within an image frame according to a detected feature. In various embodiments, the method and apparatus may readout each row in the region of interest resulting in a high resolution region and combine the pixels within the region of non-interest resulting in a low resolution region.

Methods and apparatus for pixel binning and readout

Various embodiments of the present technology may comprise methods and devices for improving the spectral response of an imaging device. The methods and devices may operate in conjunction with a pixel array and color filter array. The color filter array may comprise pattern of color filters arranged in groups. At least one group may comprise multiple same-color filters and at least one filter of a different color.

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Boise, ID, United States of America

Richard Scott Johnson