Abstract: Signals from an imager pixel photodetector are received by an amplifier having capacitive feedback, such as a capacitive transimpedance amplifier (CTIA). The amplifier can be operated at a low or no power level during an integration period of a photodetector to reduce power dissipation. The amplifier can be distributed, with an amplifier element within each pixel of an array and with amplifier output circuitry outside the pixel array. The amplifier can be a single ended cascode amplifier, a folded cascode amplifier, a differential input telescopic cascode amplifier, or other configuration. The amplifier can be used in pixel configurations where the amplifier is directly connected to the photodetector, or in configurations which use a transfer transistor to couple signal charges to a floating diffusion node with the amplifier being coupled to the floating diffusion node.

Abstract: Light sensors having a wide dynamic range are used in a variety of applications. A wide dynamic range light sensor includes an exposed photodiode light transducer accumulating charge in proportion to light incident over an integration period. Sensor logic determines a light integration period prior to the beginning of integration and the charge is reset. Charge accumulated by the exposed light transducer over the light integration period is measured and a pulse having a width based on the accumulated charge is determined.

Abstract: A circuit and method for reducing kTC noise in CMOS imagers while minimizing power dissipation is disclosed. Correlated double sampling (CDS) is performed within each pixel such that the reset voltage and the integration voltage are sampled and stored within the pixel until the voltages are forwarded to a differential amplifier for subtraction.

Abstract: Operation for global electronic shutter photodiode-type pixels. In a first mode of operation, lag is reduced through global reset of the photodiode array and fixed pattern noise is eliminated through comparison of the photosignal level and the reset level of the floating drain. In a second mode of operation, simultaneous integration and readout processes are achieved through cessation of spill charges over the transfer gate. In a third mode of operation, regulation of the reset photodiode and transfer gate enables voltage gain between the photodiode and the sense node.

Abstract: Signals from an imager pixel photodetector are received by an amplifier having capacitive feedback, such as a capacitive transimpedance amplifier (CTIA). The amplifier can be operated at a low or no power level during an integration period of a photodetector to reduce power dissipation. The amplifier can be distributed, with an amplifier element within each pixel of an array and with amplifier output circuitry outside the pixel array. The amplifier can be a single ended cascode amplifier, a folded cascode amplifier, a differential input telescopic cascode amplifier, or other configuration. The amplifier can be used in pixel configurations where the amplifier is directly connected to the photodetector, or in configurations which use a transfer transistor to couple signal charges to a floating diffusion node with the amplifier being coupled to the floating diffusion node.

Abstract: An imaging system for identifying the location of the center of mass (“COM”) in an image. In one aspect, an imaging system includes a plurality of photosensitive elements arranged in a matrix. A center of mass circuit coupled to the photosensitive elements includes a resistive network and a normalization circuit including at least one bipolar transistor. The center of mass circuit identifies a center of mass location in the matrix and includes: a row circuit, where the row circuit identifies a center of mass row value in each row of the matrix and identifies a row intensity for each row; a horizontal circuit, where the horizontal circuit identifies a center of mass horizontal value; and a vertical circuit, where the vertical circuit identifies a center of mass vertical value. The horizontal and vertical center of mass values indicate the coordinates of the center of mass location for the image.

Abstract: An imaging system for identifying the location of the center of mass (“COM”) in an image. In one aspect, an imaging system includes a plurality of photosensitive elements arranged in a matrix. A center of mass circuit coupled to the photosensitive elements includes a resistive network and a normalization circuit including at least one bipolar transistor. The center of mass circuit identifies a center of mass location in the matrix and includes: a row circuit, where the row circuit identifies a center of mass row value in each row of the matrix and identifies a row intensity for each row; a horizontal circuit, where the horizontal circuit identifies a center of mass horizontal value; and a vertical circuit, where the vertical circuit identifies a center of mass vertical value. The horizontal and vertical center of mass values indicate the coordinates of the center of mass location for the image.

Abstract: A two-transistor pixel of an imager has a reset region formed adjacent a charge collection region of a photodiode and in electrical communication with a gate of a source follower transistor. The reset region is connected to one terminal of a capacitor which integrates collected charge of the photodiode. The charge collection region is reset by pulsing the other terminal of the capacitor from a higher to a lower voltage.

Abstract: Signals from an imager pixel photodetector are received by an amplifier having capacitive feedback, such as a capacitive transimpedance amplifier (CTIA). The amplifier can be operated at a low or no power level during an integration period of a photodetector to reduce power dissipation. The amplifier can be distributed, with an amplifier element within each pixel of an array and with amplifier output circuitry outside the pixel array. The amplifier can be a single ended cascode amplifier, a folded cascode amplifier, a differential input telescopic cascode amplifier, or other configuration. The amplifier can be used in pixel configurations where the amplifier is directly connected to the photodetector, or in configurations which use a transfer transistor to couple signal charges to a floating diffusion node with the amplifier being coupled to the floating diffusion node.

Abstract: Automatic exposure adjusting device considers the image on a pixel-by-pixel basis. Each pixel is characterized according to its most significant bits. After the pixels are characterized, the number of pixels in any particular group is counted. That counting is compared with thresholds which set whether the image is over exposed, under exposed, and can optionally also determine if the image is seriously over exposed or seriously under exposed. Adjustment of the exposure is carried out to bring the image to a more desired state.

Abstract: A cascaded imaging storage system for a pixel is disclosed for improving intrascene dynamic range. Charges accumulated in a first capacitor spill over into a second capacitor when a charge storage capacity of the first capacitor is exceeded. A third capacitor may also be provided such that charges accumulated by said second capacitor spill over into the third capacitor when the charge storage capacity of the second capacitor is exceeded.

Abstract: An automatically dimming mirror includes a dimming element having variable reflectivity, the degree of reflectivity based on a control signal. An ambient light sensor is positioned to receive light from a region generally in front of the vehicle. The ambient light sensor outputs a discrete ambient light signal based on the amount of light incident on the ambient light sensor over an integration period. A glare sensor is positioned to view the scene generally behind the vehicle operator. The glare sensor outputs a discrete glare signal based on the amount of light incident on the glare sensor over an integration period. A dimming logic determines an ambient light level based on the ambient light signal. The glare integration period is determined based on the ambient light level. The glare signal resulting from the glare integration period determines a mirror glare level used to set the dimming element control signal.

Abstract: An active pixel sensor (APS) that includes circuitry to eliminate artifacts in digital images. The APS includes a comparator for comparing a signal level from a pixel to an adjusted saturation voltage to determine if the pixel is saturated. If the pixel is saturated, an associated saturation flag is stored and used to replace the signal from the pixel with a maximum value corresponding to a brightest pixel in the image.

Abstract: A pixel circuit, and a method for operating a high-low sensitivity (HLS) pixel circuit, to provide increased dynamic range in an imager. The pixel circuit combines a four transistor (“4T”) and a three-transistor plus capacitor (“3TC”) configuration in one pixel, where the 4T portion of the pixel is coupled to a high sensitivity buried photodiode region, and the 3TC portion of the pixel is coupled to a low sensitivity buried photodiode region. The pixel circuit first reads out charge from the high sensitivity photodiode region and compares it to a reset voltage, then reads out charge from the low sensitivity photodiode region. Under an alternate embodiment, multiple HLS pixels are coupled through a common floating diffusion node.

Abstract: A circuit and method for reducing kTC noise in CMOS imagers while minimizing power dissipation is disclosed. Correlated double sampling (CDS) is performed within each pixel such that the reset voltage and the integration voltage are sampled and stored within the pixel until the voltages are forwarded to a differential amplifier for subtraction.

Abstract: A frame shutter type device provides a separated well in which the storage node is located. The storage node is also shielded by a light shield to prevent photoelectric conversion.

Abstract: An image sensor is formed with shifts among the optical parts of the sensor and the photosensitive parts of the sensor. The optical parts of the sensor may include a color filter array and/or microlenses. The photosensitive part may include any photoreceptors such as a CMOS image sensor. The shifts allow images to be formed even when the light received at a given pixel location varies in angle of incidence as a function of pixel location within the array. The relative shifts among the pixel components may be, for example, plus or minus some fraction of the pixel pitch. The shift may be variable across the array or may be constant across the array and may be deterministically determined.

Abstract: Equipment on automotive vehicle is controlled by a system including at least one semiconductor light sensor having variable sensitivity to light. Each light sensor generates a light signal indicative of the intensity of light incident on the light sensor. Control logic varies the sensitivity of the light sensor and generates equipment control signals based on received light signals. Sensitivity of light sensors may be varied by changing the integration time for producing charge from light incident on light transducers, by selecting between light transducers of different sensitivity within the light sensor, by using a light transducer with a sensitivity that is a function of the amount of incident light, and the like. Controlled equipment includes devices such as automatically dimming rearview mirrors, headlamps, and moisture removal means.

Abstract: An imaging system for identifying the location of the center of mass (“COM”) in an image. In one aspect, an imaging system includes a plurality of photosensitive elements arranged in a matrix. A center of mass circuit coupled to the photosensitive elements includes a resistive network and a normalization circuit including at least one bipolar transistor. The center of mass circuit identifies a center of mass location in the matrix and includes: a row circuit, where the row circuit identifies a center of mass row value in each row of the matrix and identifies a row intensity for each row; a horizontal circuit, where the horizontal circuit identifies a center of mass horizontal value; and a vertical circuit, where the vertical circuit identifies a center of mass vertical value. The horizontal and vertical center of mass values indicate the coordinates of the center of mass location for the image.

Abstract: An imaging system for identifying the location of the center of mass (“COM”) in an image. In one aspect, an imaging system includes a plurality of photosensitive elements arranged in a matrix. A center of mass circuit coupled to the photosensitive elements includes a resistive network and a normalization circuit including at least one bipolar transistor. The center of mass circuit identifies a center of mass location in the matrix and includes: a row circuit, where the row circuit identifies a center of mass row value in each row of the matrix and identifies a row intensity for each row; a horizontal circuit, where the horizontal circuit identifies a center of mass horizontal value; and a vertical circuit, where the vertical circuit identifies a center of mass vertical value. The horizontal and vertical center of mass values indicate the coordinates of the center of mass location for the image.