Abstract: A light sensor having a light conversion element between first and second electrodes is disclosed. The light conversion element includes a body of semiconductor material having first and second surfaces. The body of semiconductor material is of a first conductivity type and has doping elements in a concentration gradient that creates a first electrostatic field having a magnitude that varies monotonically from the first surface to the second surface. A bias circuit applies a variable potential between the first and second electrodes to create a second electrostatic field having a direction opposite to that of the first electrostatic field and a magnitude determined by the potential. One of the electrodes is transparent to light in a predetermined band of wavelengths. The body of semiconductor material can include an epitaxial body having a monotonically increasing concentration of a doping element as a function of the distance from one the surfaces.

Abstract: A CCD imaging array and a charge measurement amplifier for use in such imaging arrays is disclosed. The array includes a plurality of pixels that accumulate charge when exposed to light, a readout amplifier having input and output ports. The readout amplifier has a variable gain that is set by a gain control signal. The readout amplifier also includes a reset path between the input and output ports, the path having an impedance controlled by a reset signal. A controller generates the gain control signal and the reset signal during a charge measurement cycle. Initially the gain is set to a first value after generating the reset signal. The gain is changed to a second value during the charge measurement cycle if the output signal exceeds a first threshold value. The readout amplifier can be constructed from an operational amplifier having a capacitive feedback loop.

Abstract: An imaging array having a CCD imaging array that includes a plurality of pixels that accumulate charge when exposed to light and a readout amplifier is disclosed. The readout amplifier includes an operational amplifier having an input and an output port and a feedback capacitor connecting the input and output ports and a variable impedance path between the input and output ports, the path having an impedance controlled by a reset signal. A reset signal generator generates the reset signal in three sequential phases in which the path between the input and output ports has three impedance values to provide a starting voltage at the amplifier input prior to the measurement of charge from each pixel that has reduced noise.

Abstract: Motion/Saturation detection system and method for synthesizing high dynamic range motion blur free images from multiple captures, the system and method utilizing photocurrent estimation to reduce read noise and enhance dynamic range at the low illumination end, saturation detection to enhance dynamic range at the high illumination end, and motion blur detection to ensure the photocurrent estimation is not corrupted by motion. Motion blur detection also makes it possible to extend exposure time and to capture more images, which can be used to further enhance dynamic range at the low illumination end. The present invention operates completely locally, making it well suited for single chip digital camera implementations.

Abstract: The dynamic range and the noise immunity of a digital imaging system are increased by basing an estimate of the illumination on a sensor on a series of measurements of the accumulated illumination at intervals within an exposure period. The measuring may occur destructively, or alternatively the photocurrent of the sensor may continue to accumulate over the exposure period. The estimate may use statistical signal processing of the measurements, based on various noise models and various optimization criteria. The estimate may be computed recursively over the multiplicity of measurements, using a set of recursive values that may include but is not limited to the estimated illumination, a current weighting coefficient, a variance of the current measurement and a variance over the series of measurements.

Abstract: The present invention includes an imaging apparatus having an imaging array, readout amplifier, and controller. The imaging array includes a plurality of pixels that accumulate charge when exposed to light. The readout amplifier receives charge from the pixels and generates a pixel signal indicative of the amount of charge received. The controller causes the charge from a plurality of the pixels to be added together to form a sum charge that is received by the readout amplifier. The imaging array can include a plurality of columns of pixels, and the controller causes the charge from a plurality of pixels in one of the columns to be added together to form a partial sum charge that is included in the sum charge. The readout amplifier can include a horizontal shift register, and the partial sum charge can be generated in the shift cells.

Abstract: An imaging array having a CCD imaging array that includes a plurality of pixels that accumulate charge when exposed to light and a readout amplifier is disclosed. The readout amplifier includes an operational amplifier having an input and an output port and a feedback capacitor connecting the input and output ports and a variable impedance path between the input and output ports, the path having an impedance controlled by a reset signal. A reset signal generator generates the reset signal in three sequential phases in which the path between the input and output ports has three impedance values to provide a starting voltage at the amplifier input prior to the measurement of charge from each pixel that has reduced noise.

Abstract: A method for improving SNR without reducing dynamic range in a CMOS video sensor system under low illumination is described, wherein the CMOS video sensor system employing self-reset DPS architecture includes pixel level A/D conversion and wherein each DPS pixels is capable of resetting itself whenever a corresponding diode reaches saturation during integration time, the method comprising the steps of eliminating global frame reset for the self-reset DPS pixels, capturing and storing a plurality of frames, extending integration time beyond frame readout time, and generating frame images using one or more previously stored frames.

Abstract: A CMOS DPS image sensor architecture for improving SNR and dynamic range is presented. The CMOS DPS architecture includes self-reset digital pixels capable of collecting more charge than the physical well capacity. A method for improving SNR without reducing dynamic range in a CMOS video sensor system under low illumination is described, wherein the CMOS video sensor system employing self-reset DPS architecture includes pixel level A/D conversion and wherein each DPS pixels is capable of resetting itself whenever a corresponding diode reaches saturation during integration time.

Abstract: Structures and methods for three-dimensional image sensing using high frequency modulation includes CMOS-implementable sensor structures using differential charge transfer, including such sensors enabling rapid horizontal and slower vertical dimension local charge collection. Wavelength response of such sensors can be altered dynamically by varying gate potentials. Methods for producing such sensor structures on conventional CMOS fabrication facilities include use of “rich” instructions to command the fabrication process to optimize image sensor rather than digital or analog ICs. One detector structure has closely spaced-apart, elongated finger-like structures that rapidly collect charge in the spaced-apart direction and then move collected charge less rapidly in the elongated direction. Detector response is substantially independent of the collection rate in the elongated direction.

Abstract: Effective differential dynamic range in a differential pixel detector is increased by avoiding saturation effects due to common mode contribution in optical energy to be detected. Photocurrent generated by each photodetector pair is directly integrated by an associated capacitor over an integration time T. Within time T, before either integrated capacitor voltage reaches Vsat for the photodetector, at least one of the capacitors is reset to a voltage such that the desired differential detector signal is still determinable. Reset may be generated externally or internally to the differential pixel detector.

Abstract: Structures and methods for three-dimensional image sensing using high frequency modulation includes CMOS-implementable sensor structures using differential charge transfer, including such sensors enabling rapid horizontal and slower vertical dimension local charge collection. Wavelength response of such sensors can be altered dynamically by varying gate potentials. Methods for producing such sensor structures on conventional CMOS fabrication facilities include use of “rich” instructions to command the fabrication process to optimize image sensor rather than digital or analog ICs. One detector structure has closely spaced-apart, elongated finger-like structures that rapidly collect charge in the spaced-apart direction and then move collected charge less rapidly in the elongated direction. Detector response is substantially independent of the collection rate in the elongated direction.

Abstract: Effective differential dynamic range in a differential pixel detector is increased by avoiding saturation effects due to common mode contribution in optical energy to be detected. Photocurrent generated by each photodetector pair is directly integrated by an associated capacitor over an integration time T. Within time T, before either integrated capacitor voltage reaches Vsat for the photodetector, at least one of the capacitors is reset to a voltage such that the desired differential detector signal is still determinable. Reset may be generated externally or internally to the differential pixel detector.

Abstract: A sensor system is provided for determining a deployment level of an airbag in a vehicle. A light source of the sensor system emits light onto a region around a vehicle seat. An array of light-sensitive pixels which capture reflected light from the scene, including reflected light that originated from the light source. Processing resources are provided that determine depth information for an object in the scene based on a time-of-flight characteristic of the reflected light from the light source captured on the array. The processing resources may be configured to determine occupancy data for the object based on the captured reflected light from the scene.

Abstract: The invention is related to a mechanical x-y-axis adjustable stage, which is designed for microscopic electro-physiological studies. The stage adopted a three-layer flat-slab structure. The up-most layer was a bearing layer on which other equipment could be mounted. The middle layer and bottom layer were guide layers, and rails for x-axis or y-axis guiding were installed. In order to move the top layer smoothly along two-dimension relative to the bottom layer, the three layers were jointed using grooved rails. By moving the top layer accordingly along the x-axis and y-axis, biological sample (animal/cells) as well as other instruments such as electrophysiological probes and manipulators could be moved smoothly and flexibly, and specific visual fields could be defined without moving the complex microscope system as well as other optical components. Therefore, the present invention has broad application values, for example two-electrodes electrophysiological recordings.

Abstract: A functional block for a CMOS circuit within the core of an integrated circuit chip and a method of making the same is disclosed. The functional block uses both thick and thin gate oxide transistors which reduces the leakage current and increases the voltage swing while permitting the device scaling in circuits made in CMOS technology. Within the functional block, the distance between a thick oxide transistor and a thin oxide transistor is chosen based on a transistor stability criterion. The thick and thin oxide transistors can be connected to identical or different voltage sources. Further, a transistor within a functional block can be chosen to be thick or thin oxide transistor based on a leakage current threshold or a voltage swing threshold.

Abstract: The dynamic range and the noise immunity of a digital imaging system are increased by basing an estimate of the illumination on a sensor on a series of measurements of the accumulated illumination at intervals within an exposure period. The measuring may occur destructively, or alternatively the photocurrent of the sensor may continue to accumulate over the exposure period. The estimate may use statistical signal processing of the measurements, based on various noise models and various optimization criteria. The estimate may be computed recursively over the multiplicity of measurements, using a set of recursive values that may include but is not limited to the estimated illumination, a current weighting coefficient, a variance of the current measurement and a variance over the series of measurements.

Abstract: Motion/Saturation detection system and method for synthesizing high dynamic range motion blur free images from multiple captures, the system and method utilizing photocurrent estimation to reduce read noise and enhance dynamic range at the low illumination end, saturation detection to enhance dynamic range at the high illumination end, and motion blur detection to ensure the photocurrent estimation is not corrupted by motion. Motion blur detection also makes it possible to extend exposure time and to capture more images, which can be used to further enhance dynamic range at the low illumination end. The present invention operates completely locally, making it well suited for single chip digital camera implementations.

Abstract: A CMOS DPS image sensor architecture for improving SNR and dynamic range is presented. The CMOS DPS architecture includes self-reset digital pixels capable of collecting more charge than the physical well capacity. A method for improving SNR without reducing dynamic range in a CMOS video sensor system under low illumination is described, wherein the CMOS video sensor system employing self-reset DPS architecture includes pixel level A/D conversion and wherein each DPS pixels is capable of resetting itself whenever a corresponding diode reaches saturation during integration time.

Abstract: A method for improving SNR without reducing dynamic range in a CMOS video sensor system under low illumination is described, wherein the CMOS video sensor system employing self-reset DPS architecture includes pixel level A/D conversion and wherein each DPS pixels is capable of resetting itself whenever a corresponding diode reaches saturation during integration time, the method comprising the steps of eliminating global frame reset for the self-reset DPS pixels, capturing and storing a plurality of frames, extending integration time beyond frame readout time, and generating frame images using one or more previously stored frames.