摘要:
A hybrid imaging array and method for using the same is disclosed. The image array includes a low-light imaging array and a color imaging array. The two imaging arrays can be utilized separately or in conjunction with one another. The low-light imaging array is optimized for night vision or situations in which the light levels are too low to allow a conventional color image to be formed by the color imaging array. The color imaging array is optimized for daylight or color photography. The low-light imaging array can be utilized in conjunction with the color imaging array to provide a color image with reduced noise.
摘要:
An image sensor and a method for using the same are disclosed. The image sensor includes an array of pixel sensors, a signal digitizing circuit, and a digitizing controller. The array of pixel sensors includes a plurality of pixel sensors. Each pixel sensor includes a photodetector, a charge conversion circuit, and a gate transistor. The charge conversion circuit generates a voltage signal that is related to a charge on the photodiode, and the gate transistor couples the voltage signal to a bit line in response to a first signal. The signal digitizing circuit converts the voltage signal to a plurality of output digital values. Each output digital value has a different level of digitization noise. One of the output digital values is selected for output in response to an output selection signal that is generated by the digitizing controller.
摘要:
A CCD containing circuit and method for making the same. The circuit includes a CCD array and a protection circuit. The CCD array is constructed on an integrated circuit substrate and includes a plurality of gate electrodes that are insulated from the substrate by an insulating layer. The gate electrodes are connected to a conductor bonded to the substrate. The protection circuit is also constructed on the substrate. The protection circuit is connected to the conductor and to the substrate and protects the CCD array from both negative and positive voltage swings generated by electrostatic discharge events and the like. The protection circuit and the CCD can be constructed in the same integrated circuit fabrication process.
摘要:
An image sensor having a two-dimensional array of CMOS pixel sensors, a row decoder and a column decoder is disclosed. The two-dimensional array of CMOS pixel sensors is organized as a plurality of rows and columns that are addressed with the aid of row and column decoders. At least one of the column decoder or the row decoder is located between two of the rows or two of the columns, respectively. X-rays are converted to light that is detected by the image sensor by a layer of scintillation material that overlies the two-dimensional array. The internally located decoder or decoders facilitate sensors in which the two-dimensional array includes a rectangular array having a chamfered corner such that rows or columns that extend into the chamfered corner have lengths that are less than rows or columns, respectively, that do not extend into the corners.
摘要:
An image sensor having a first substrate on which a CCD array is fabricated in a first fabrication system is disclosed. The CCD array includes a node through which charge from the pixels passes during a readout operation. The first substrate also includes a first FET fabricated on the first substrate in the first fabrication system, the first FET having a gate connected to the node and a source or drain connected to a first conducting pad on the first substrate. A capacitor connects the node to a second conducting pad on the first substrate. A switch is connected across the first capacitor such that the first capacitor is shorted when the first switch is closed. The first switch is controlled by a reset signal on a third conducting pad on the first substrate. The first substrate can be connected to a second substrate having amplification and control circuitry.
摘要:
An active pixel sensor comprises a photodiode providing a photodiode output current indicative of an intensity of light incident the photodiode and an integrator circuit electrically coupled to the photodiode. The integrator circuit is configured to provide a pixel voltage representing an integration of the photodiode output current when the photodiode is exposed to light and dark leakage current through the photodiode when the photodiode is not exposed to light. The integrator circuit is configured to set a reverse bias voltage on the photodiode and respond to at least one control input to set the reverse bias voltage to a first level. The active pixel sensor comprises a feedback loop configured to receive the pixel voltage and control the integrator circuit to adjust the reverse bias voltage to substantially reduce the dark leakage current through the photodiode to a desired level.
摘要:
An image sensor and method of sensing an image provides a variable amplifier at each pixel, thereby expanding the dynamic range of the sensor. An image sensor core (500) comprises a plurality of pixel sensors (510). Each pixel sensor preferably includes a photosensitive element (310), a variable amplifier (312), and an analog-to-digital converter (“ADC”) (314). The ADC (512) includes a comparator (512) coupled to a latch/shift register (514). The comparator (512) receives the output of the variable amplifier (312) and a ramp signal and produces an output when the ramp signal exceeds the amplifier (312) output. The latch/shift register (514) latches a count signal corresponding to the ramp signal when triggered by the comparator (512). In operation, the photosensitive element (310) is exposed to light for a first integration period. The variable amplifier (312) amplifies the resulting photocharge by the maximum possible amount. The ADC (314) converts the photocurrent to a digital signal and latches the five most significant bits in memory (514). These five bits are provided in parallel to the variable amplifier (312) to set the amplification level. Then, the photosensitive element (310) is exposed to light for a second integration period and the resulting photocharge is amplified at the set amplification level. The output of the amplifier (312) is digitized by the ADC (314) and the latch/shift register (514) stores the 12-bit result. The five bits selecting the amplification level and the 12-bit result provide the image sensor with 17 bits of dynamic range.
摘要:
An improved image sensor constructed from a photodiode and a transimpedance amplifier having an input connected to the photodiode. The present invention utilizes a clamping circuit to prevent the potential at the input of the transimpedance amplifier from causing the photodiode to become forward biased. In the preferred embodiment of the present invention, the transimpedance amplifier includes a transistor connecting the input to the output, and the clamping circuit includes a circuit for holding the gate of the transistor at a clamping potential.
摘要:
An amplifier for measuring the charge stored on a source capacitor having a capacitance Cpd. The amplifier includes an opamp having a signal input, reference input and output; the first terminal of the source capacitor is connected to the signal input. The amplifier includes a reset switch for shorting the signal input and the output of the opamp, and a capacitive network. The capacitive network connects the signal input and the output of the opamp, and provides a capacitance of CT between the signal input and the output of the opamp wherein CT
摘要:
An imaging array and a method for operating the same are disclosed. The imaging array includes a plurality of light pixels and a sense amplifier. Each light pixel includes a photodetector that generates and couples a signal indicative of a light exposure to a light pixel node, a readout circuit, and a mixer that mixes a signal on the light pixel node with a pixel oscillator signal. The sense amplifier includes an input node that receives a signal from each light pixel, one light pixel at a time. The sense amplifier also includes a high pass filter that attenuates signals with frequencies less than a cutoff frequency and a mixer that demodulates the signal from the filter to provide a signal that is related to the potential on the light pixel node of the light pixel connected to the first input node.