Abstract: When making a potential of a floating node 0V at the time of nonselection, electrons leak from the floating node to a photodiode and noise is generated. A MOS type solid-state imaging device comprised of unit pixels 10, each having a photodiode 11, a transfer transistor 12 for transferring a signal of this photodiode 11 to a floating node N11, an amplifier transistor 13 for outputting a signal of the floating node N11 to a vertical signal line 22, and a reset transistor 14 for resetting the floating node N11, arranged in a matrix, wherein, as a buffer final stage 29 for driving a drain line 23, a buffer final stage having an inverter configuration formed by arranging a P-type MOS transistor on a ground side is used, thereby making the potential of the floating node N11 for example 0.5V at the time of nonselection and preventing electrons from leaking to the photodiode 11 through the transfer transistor 12.

Abstract: An imaging apparatus including a lens unit and an image pickup unit. The lens unit includes an optical system that projects a subject image onto an imaging device, the imaging device that converts the subject image into an electric signal, an imaging device driving part that drives the imaging device, an signal processing device that converts the electric signal from the imaging device into a digital signal, and a first connection part that connects the lens unit to the imaging pickup unit mechanically and electrically. The imaging pickup unit includes an electric power supply part, a second connection part that connects the lens unit to the imaging pickup unit mechanically and electrically, voltage supply lines that supply output voltage to the lens unit, and a voltage generating circuit that generates the output voltage supplied to the voltage supply lines.

Abstract: An image capturing device having a function of clamping an image signal. When the image capturing device is activated, a synchronous signal generating section begins creation of a horizontal synchronous signal, and a counter begins counting a pulse of the horizontal synchronous signal. When the counted value reaches a predetermined value, the clamping capability control section changes the level of a clamp mode signal to an H level. During a period from the start of power supply to the image capturing device to the raising of the level of a clamp mode signal to an H level, a clamp pulse generating section sets a longer width for a clamp pulse than in a normal operation so that a switch element of a clamping circuit remains in an on state in a longer period, whereby a smaller time constant for clamping is set. After elapse of a predetermined period, the switch element is controlled so as to remain in an ON state in a normal period, which is relatively short, whereby a larger time constant for clamping is set.

Abstract: Preview mode low-resolution readouts occur, and then a shutter button on a camera is pressed, which causes an image sensor cleanout operation to occur. Following the cleanout, a high-resolution readout occurs. As rows of sensor values are read, the first rows are rows corresponding to a pre-defined horizontally-extending shielded area. There are no valid area sensor elements to either side of the horizontally-extending area. Data values read from the horizontally-extending area are used to determine optical black (OB) values that are then used to adjust the valid area values read out of the image sensor in that same frame. The same OB values are used throughout the adjusting of the valid area values of the entire frame. No values from the preview readouts are used in the OB value determination, so there is a clean break between the preview mode OB level and the high-resolution capture OB level.

Abstract: An image capture apparatus includes first and second pixels. Each pixel has a sensor and a reading portion for reading out a signal from the sensor to an output line. The apparatus further includes a correcting section for changing a correction signal in accordance with waiting time in which signals from the first and second pixels are held and for correcting noise components contained in image signals output from the first and second pixels in accordance with the correction signal. Waiting times in which the image signals are held in the first and second pixels are different from each other and the noise components are generated due to the different waiting times.

Abstract: In a unit pixel of a CMOS image sensor which compensates for a dark current generated in a photo diode to enhance its driving range, the photo diode generates a charge in accordance with a received light amount. A drive transistor has a gate for receiving the charge in the photo diode to output as an electrical signal, and a drain to which a power voltage is applied. A saturation detector receives a gate voltage of the drive transistor and judges the drive transistor saturated if an output voltage is smaller than a preset reference voltage. A switch connects or disconnects between the power voltage and the gate of the drive transistor in response to the judgment of the saturation detector.

Abstract: An apparatus has an image sensing device, and a signal processing device for performing a first image sensing operation for making the image sensing device perform an image sensing operation in an exposure state to obtain a sensed image signal, and a second image sensing operation for making the image sensing device perform an image sensing operation in a non-exposure state to obtain a sensed image signal, and processing the sensed image signal obtained by the first image sensing operation by the sensed image signal obtained by the second image sensing operation. The signal processing device determines in accordance with the image sensing time of the first image sensing operation whether or not the second image sensing operation is performed.

Abstract: An electronic imaging system includes a method for calibrating an image sensor having a array of pixels each used in capturing an image, the method comprising the steps of capturing first dark floor values at a first time from substantially all of the pixels in the array, storing the first dark floor values, capturing second dark floor values at a second time from substantially all of the pixels in the array, using the first and second dark floor values to compute third dark floor values, using the third dark floor values when processing the captured image.

Abstract: A signal processing apparatus including a clamp pulse generation circuit for generating a clamp pulse in synchronization with an image signal, a clamp circuit for clamping a signal of a black reference value in response to the clamp pulse, and a defect detection circuit for detecting a defective pixel included in an optical black area, wherein the clamp pulse generation circuit cancels a rise of the clamp pulse when a position of the defective pixel detected by the defect detecting circuit and a position of a rise state of the clamp pulse overlap with each other.

Abstract: At least one exemplary embodiment is directed to an imaging apparatus including an image sensor including a light-shielded pixel area, a comparison unit configured to compare a light-shielded pixel output value output from at least a part of the light-shielded pixel area with a plurality of preset determination values, a counting unit configured to count a result of comparison performed by the comparison unit with respect to each of the plurality of determination values, and a calculation unit configured to estimate an amount of dark current generated in the image sensor based on a result of counting performed by the counting unit.

Abstract: A signal processing device includes a memory which stores correction data in advance. The signal processing device modifies the correction data stored in the memory on the basis of an image sensing signal obtained by causing an image sensing unit to perform image sensing operation in a non-exposure state. The signal processing device corrects by using the modified correction data an image sensing signal obtained by causing the image sensing unit to perform image sensing operation in an exposure state.

Abstract: Image sensor with a successive approximation A/D converter that automatically compensates for black level and provides a signal indicative of the difference between the reset level and the signal level. Black level for each of a plurality of color pixels may be obtained. This may be obtained from, for example, an image sensor with intentionally darkened pixels. Levels from these pixels are sampled, and an average of these pixels is used to form a black level for similarly-colored pixels. That black level is stored, and used to drive a D/A converter. Another D/A converter forms the actual conversion, and is compared to a reference. The reference is selected such that the output signal is automatically compensated for black level, and also corresponds to the difference between signal and reset.

Abstract: The present invention provides an imaging element that can prevent misappropriation by a third party, an imaging device disposed with the imaging element, and a method of deterring misappropriation of the imaging element. In a CCD (imaging element) disposed with plural photodiodes for breaking down an image into plural pixels to generate image information representing the image and an OB portion (optical black portion) that shields a partial region of a light-receiving region corresponding to the plural photodiodes in order to determine an output level when the image is black, an opening for guiding light to the photodiodes is disposed at a predetermined position in the OB portion.

Abstract: A method for reducing the noise equivalent temperature difference associated with imaging devices having a detection array including micro-cantilevers and a charged-coupled device or a complementary metal oxide semiconductor imager is presented. The method includes calculating horizontal and vertical pixel ratios based upon the number of receptor pixels and micro-cantilever pixels, defining composite pseudo-pixels comprised of at least two receptor pixels, capturing at least one frame of an image, calculating the composite intensity for each composite pseudo-pixel based on the intensities of the receptor pixels therein, and reconstructing each frame so that receptor pixels within each composite pseudo-pixel are displayed with the appropriate composite intensity. While the present method lowers pixel resolution, the composite pseudo-pixels maintain image resolution within the reconstructed image.

Abstract: A method for reducing shutter latency while maintaining low dark current in the imager and minimizing energy consumption in a digital camera, the method including the steps of providing an imager operating in accumulation mode; and substantially continuous flushing of charges from the imager before capturing an exposure of an image with a time between vertical transfers greater than or equal to time between vertical transfers during normal image readout so that, if continuous flushing for a time necessary to readout substantially all rows of pixels has occurred, the exposure may be captured with substantially zero latency.

Abstract: There is a need for providing a variable amplifier circuit suited for a semiconductor integrated circuit and a high-performance camera preprocessing LSI using the variable amplifier circuit. At first timing, a first input capacitor acquires a first signal. An amplifier circuit amplifies a second signal acquired to the second input capacitor according to a gain corresponding to a capacity ratio between the second input capacitor and a feedback capacitor composed of a variable capacitor device. At second timing, the second input capacitor acquires a second signal. The amplifier circuit amplifies the first signal according to a gain corresponding to a capacity ratio between the first input capacitor and the feedback capacitor. A variable gain amplifier circuit interleavingly amplifies the first signal and the second signal in synchronization with the first timing and the second timing.

Abstract: An image-signal processing apparatus (1) designed to process the signals output from a CCD image sensor (10) that reads pixel data for one screen, line by line, divides the pixel data into a plurality of channels and outputs the pixel data thus divided. The image-signal processing apparatus (1) detects and corrects the black level of each pixel data item that the image sensor (10) has output for one channel. The image-signal processing apparatus (1) detects and corrects the gain difference between channels, which pertain to the pixel data items output from the image sensor (10). Hence, the apparatus (1) can correct the black level of each pixel data item and the gain difference between channels with high accuracy, when used in combination with an image sensor that divides pixel data into a plurality of channels.

Abstract: In order to eliminate noises contained in signals output from a photoelectric conversion unit, an image processing apparatus is provided with a photoelectric conversion unit including a pixel and a noise correction unit for correcting noises in a signal output from a pixel in accordance with noise information obtained from the pixel during two or more arbitrary different accumulation times.

Abstract: A method of processing image data comprises obtaining a set of weighting coefficients to be used in calculating replacement pixel values associated with defective sensing elements of a detector array, the set of weighting coefficients including at least one negative weighting coefficient, obtaining information identifying one or more defective sensing elements of the detector array, receiving image data from the detector array, calculating a weighted average of pixel values from sensing elements adjacent to a first defective sensing element of the detector array using at least some of the weighting coefficients, and assigning the weighted average to be a replacement pixel value for the first defective sensing element. An apparatus for processing image data according to the method is also described.

Abstract: A solid state image sensor has an array of pixels in which each column has a reset voltage line and a read line. The sensor is reset and read a row at a time, with reset-related values held in a frame buffer for subsequent subtraction from read values. Reset-related values are derived in each column by sampling the voltage during reset on one capacitor and the voltage on release of reset on a second capacitor, and differencing these values to provide an output for the frame buffer. This provides a reduction in the size of frame buffer which would otherwise be required.

Abstract: A fixed pattern noise subtraction method in a digital imaging system incorporating a digital image sensor includes: acquiring a reference image of the digital image sensor when the digital image sensor receives no illumination, storing a reference value of an operating parameter associated with the reference image where the reference image is indicative of the fixed pattern noise associated with the digital image sensor, storing a model describing the behavior of the fixed pattern noise as a function of the operating parameter. Then, the method continues with acquiring a first image, measuring a current value of the operating parameter associated with the first image, calculating a noise prediction image by extrapolation of the reference image in accordance with the model and based on the current value and the reference value of the operating parameter, and subtracting the noise prediction image from the first image to generate a final image.

Abstract: A solid-state imaging apparatus includes: a defective pixel detector (8) for extracting, from a signal output by a frame-reading solid-state image pickup element (2), pixel data for a target pixel for which a determination is to be made and pixel data for peripheral pixels thereof, and for employing pixel data for a pixel, selected from among the peripheral pixels, in the same filter as the target pixel, to determine whether the target pixel is a defective pixel; and a defective pixel correction circuit (9) for employing the pixel data for the peripheral pixels to correct pixel data for the defective pixel. With this configuration, the output signal of the defective pixel can be corrected without spreading the effect produced by the defective pixel to the peripheral pixels, and a natural image can be displayed.

Abstract: An electronic camera according to the present invention includes: an image-capturing element that outputs image-capturing signals; a shutter device that allows subject light pass through to the image-capturing element or shields the image-capturing element from the subject light; an image-capturing circuit that engages the image-capturing element in an image-capturing operations over a predetermined length of time to output to a first image-capturing signal while the subject light is allowed to pass through to the image-capturing element and also engages the image-capturing element in an image-capturing operation over a predetermined length of time while the image-capturing element is shielded from the subject light; a signal correction circuit that executes a signal correction by subtracting the second image-capturing signal from the first image-capturing signal; and a control circuit that controls the image-capturing circuit so as to set an upper limit to the length of the image-capturing operation executed

Abstract: A digital camera includes a CCD operating with accumulation mode clocking for capturing an electronic representation of an image; and two or more clocks operatively and respectively connected to each phase of the two or more phases for initiating flushing of excess current, wherein, to initiate flushing, a time the clocks are at a high level are substantially the same, and a time the clocks are at a low level can be selected at any duration between a minimum width at which dark current starts to substantially increase and twice its normal operating duration during image readout and for reducing power consumption while retaining minimum dark current and for having a substantially uniform dark field.

Abstract: A method and apparatus are described for image sensor optimization. According to an embodiment of the invention, a method comprises capturing an image with an image sensor, the image sensor comprising a plurality of pixels; obtaining an output relating to the image from a first pixel of the plurality of pixels; and normalizing the output from the first pixel to correlate with photon flux striking the image sensor.

Abstract: The present invention is a black clamp circuit for an electronic imager having black reference pixels. The circuit includes an average value circuit determining an average of a number of the black reference pixels, a correction circuit determining the black level correction from the average, and a modifier circuit modifying image pixels with the black level. The average value is used in a real time feedback loop that removes offset errors in the signal processing chain and establishes a corrected black level in output image data. The feedback can be either digital or analog. The correction circuit can include a comparator that allows a hysteresis in the feedback to avoid hunting as well as multiple levels of feedback based on several thresholds. The corrected black level can also be controlled by a digital transfer function. The black clamp circuit can be used for a series of images, an image frame and an image line.

Abstract: An optical sensor circuit has a first optical sensor that outputs a signal according to the amount of received light on an opened light-receiving surface, a second optical sensor that is provided near the first optical sensor and outputs a signal according to the amount of received light on a shielded light-receiving surface, and a difference calculating circuit that calculates a difference between the output signal of the first optical sensor and the output signal of the second optical sensor and outputs the difference.

Abstract: The invention provides an imaging apparatus in which when a difference in sensitivity between two photosensitive elements having different sensitivities is used to achieve a wide dynamic range, a correction amount of a low sensitivity portion is determined from information of a high sensitivity portion to reduce a burden of an internal process. A black level correction value of a dependent photosensitive pixel is calculated by multiplying a black level correction value of a main photosensitive pixel by the ratio of the cell area of the main photosensitive pixel to the cell area of the dependent photosensitive pixel. It is not necessary to perform control to capture an imaging signal from the dependent photosensitive pixel belonging to an OB portion for determining the black level correction value of the dependent photosensitive pixel.

Abstract: A camera comprises a multitap imager, separate digitizing channels for each imager tap, adjustments for channel gain and black level, a pattern generator, and a channel balancer. The channel balancer compares adjacent pixels and sums the differences in levels over many frames. Any accumulated difference is used as a feedback signal to drive the summing to a minimum. If the imager is temporarily hooded, the feedback is used to balance black levels between the channels. If the imager is operating, the feedback is used to dynamically adjust the channel gain of one channel to match the other. A pattern generator is used once during calibration to generate a test pattern in the digitizing channels that makes it obvious to a framegrabber how exactly to restitching the various lanes or zones of the whole image frame back together.

Abstract: In a CMOS image sensor, correlated double sampling (CDS) is performed to reduce RESET noise: a first sampled signal is detected after RESET for the pixels, a second sampled value is determined at the end of an exposure time, and a differential signal substantially free from RESET noise is formed by subtracting the first sampled value from the second sampled value. In order to improve the deficient brightness dynamics, the first sampled signal is obtained only after a certain delay interval according to the invention so that this signal too contains not only a noise component but also brightness information. If the second sampled signal exceeds the saturation limit, only the accordingly scaled first sampled signal is used as the wanted signal. In this case the wanted signal has RESET noise but the latter is of almost no importance at high brightnesses. One achieves a multiplication of the brightness dynamics of a CMOS image sensor.

Abstract: An image-sensing apparatus for compensating video signal of a plurality of channels, adds an electric charge of a pilot signal on a signal vertically transferred in an image-sensing device 11. A pixel area of the image-sensing device 11 is divided into a plurality of pixel areas to obtain an output signal of a plurality of channels. The pilot signal is add to an output signal of each pixel area corresponding to each channel for twice a field period, and for different electric potential. The control circuit 15 obtains a difference between the two pilot signals in one filed period, and controls the gain compensation 17 to make the pilot signal level in each channel equal. Additionally, the pilot signal is not used for compensation but the previous signal is used when a smear element is detected from the output signal of each channel.

Abstract: In an X-ray film image reading apparatus, dark output distribution data of a CCD line sensor is corrected by using correction data. In order to suppress the influence of random noises on the correction data, a dark distribution correction data calculation circuit 10 calculates an average value or mode value of dark distribution outputs of all or some pixels of a CCD line sensor or a dark distribution output of the CCD line sensor subjected to a spatial low-pass filtering process, and stores it in a dark distribution memory as correction data. Next, a light source is turned on, and a subtractor subtracts the stored correction data from an output of the line sensor read from an X-ray film while the light source is turned on.

Abstract: An OB level difference is calculated from the luminance signal levels of at least two frames which are exposed for proper exposure time and for exposure time different from the proper exposure time, and the OB level difference is corrected in an input step of a signal processing circuit. Calculation of the OB level difference is performed regularly from immediately after power on of the equipment, the OB level difference obtained in each frame is multiplied, and a value obtained by dividing the multiplied OB level difference by the number of sampled frames is designated as a correction value.

Abstract: Briefly, in accordance with one embodiment of the invention, a digital camera includes: a digital imaging array including a plurality of pixels, and image processing circuitry to process the digital pixel output signals produced by the imaging array. The imaging processing circuitry is adapted to process saturated digital pixel output signals differently from non-saturated digital pixel output signals. In accordance with another embodiment of the invention, at least one integrated circuit includes image processing circuitry. The processing circuitry is adapted to process digital pixel output signals produced by a digital imaging array. The image processing circuitry is further adapted to process saturated digital pixel output signals differently from non-saturated digital pixel output signals.

Abstract: A CCD photoelectrically converts image information obtained from optically reading an original image, line by line, and outputs an image signal. Several of the photoelectric sensors of a CCD of the CCD portion form an optical black portion. A black shading correcting portion corrects the image signal using a black reference level. The black reference level is obtained from the optical black portion of the CCD for each line during an operation of the reading of the original image. The black reference level used by said black shading correcting portion for each line is obtained using black reference values, each of the black reference values being data of the optical black portion for a respective one of a plurality of lines.

Abstract: In an image pickup apparatus and image pickup method, an image pickup area where a plurality of pixels each having at least first and second photoelectric conversion sections are arranged in a depth direction is used to pick up an object image, signals from the first and second photoelectric conversion sections are obtained in case that the image pickup area is light-shielded, and differential processing between a signal obtained in the first photoelectric conversion section in case that the image pickup area is light-shielded and a signal obtained in the first photoelectric conversion section by picking up an object image in the image pickup area, and differential processing between a signal obtained in the second photoelectric conversion section in case that the image pickup area is light-shielded and a signal obtained in the second photoelectric conversion section by picking up an object image in the image pickup area are performed, so that correction of image pickup signals is performed.

Abstract: Upon depression of a shutter key of a key input unit, a sensed image (DATA1) is captured by exposing a CCD for exposure time T1 with a mechanical shutter opened, and a dark frame image (DATA2) is captured by exposing the CCD for exposure time Ta with the mechanical shutter closed. A correction value corresponding to exposure time T1 is then determined by looking up a correction data table stored in a storage area of a data memory, and DATA2 is corrected using the determined correction value. By subtracting the corrected DATA2 from DATA1, a dark output component contained in DATA1 is removed.

Abstract: An image processing apparatus for processing an image sensed by an image sensing element such as a CCD sensor includes a dark correction circuit for making dark correction of the image, a defect correction circuit for correcting a defective pixel in the image using other pixels, and a controller for controlling the shares of dark correction by the dark correction circuit and defect correction by the defect correction circuit on the basis of information which pertains to image sensing such as an ISO speed, temperature, and accumulation time.

Abstract: An apparatus and method of processing images in a digital camera and improving the quality of images produced by camera processing software. In low-light digital camera photography, a dark frame image is subtracted from an original picture image to form a resulting image. The resulting image formed from the dark frame subtraction is evaluated for negative and invalid pixel values. Each negative and invalid pixel value is replaced using a pixel replacement algorithm with appropriate positive values.

Abstract: A method, apparatus, and system for accounting for dark current in the output of an imaging array is presented. A dark current monitor on the monolithic semiconductor imaging array is provided. The dark current monitor may be darkened pixels of the imaging array, darkened pixels of another array, or a temperature monitor and associated circuitry necessary to calculate relative dark current from the monitored temperature.

Abstract: The control inputs of reset switch elements 41 to 45 are commonly connected to a row reset line 51. In a line black clamp type, cathodes as reset ends of photodiodes (31) of optical black pixels 21 to 23 are commonly connected to a potential averaging line 30. In a frame black clamp type, potential averaging lines are connected similarly to respective pixel rows on the vertical scanning start side of an optical black pixel region, and the potential averaging lines may be commonly connected to each other to operate just like one pixel row. A first block includes a pixel array and a vertical scanning circuit, while a second block includes sample and hold circuits, a horizontal scanning circuit, an amplifier and an A/D converter 19.

Abstract: The present invention provides a method and apparatus for calibrating a black level in an imager to reduce flicker noise. A first and a second range is set. The first range corresponds to a range that is larger than a noise level at a highest PGA gain. The second range corresponds to a range that is smaller than a level which reduces an ADC dynamic range too much due to a large black level. The ranges may be adjusted to changes in an imager in real time. When the black level is within the second range a determination is made as to whether the black level has been calibrated before. When it has, the DAC output is held constant. Otherwise the DAC code is adjusted such that the black level is moved toward the first range. A small step size is used in adjusting the DAC code in order to reduce flicker. Step sizes may be adjusted according to the black level in relation to the ranges. A small step size is used when the black level is within the second range.

Abstract: An imager in which two adjacent pixels share row and reset lines and a row selection circuitry while the output transistors of the two pixels are configured as a differential amplifier. In operation, both pixels are reset at the same time, causing differential reset signals to be output from the amplifier. The charge from the first pixel is readout and a differential pixel signal for the first pixel is output from the amplifier. Because the reset and pixel signals are differential signals generated within the pixels, they are free from common-mode noise. Correlated double sampling can be used to obtain the pixel output value, which is also free from common-mode noise, from the differential reset and pixel signals. The second pixel may be readout in the same manner. Because the two pixels are sharing circuitry, the pixels have decreased fill factor and complexity as well.

Abstract: When a signal output by a solid-state image sensing device is clamped to a predetermined reference potential, a high voltage generated in a transfer suspension period after the clamping as generally supplied to an A/D converter is generated. A sample/hold output Va is clamped to a clamp level Vref over a period of time between a halfway point of time of a signal of a picture element preceding ahead by one line and the end of an inhibit period of transfer clocks of a signal output by an empty transmission unit via a first clamp pulse and a sample/hold output for the second picture element, or a subsequent one of an OPB unit is clamped to the clamp level via a second clamp pulse to prevent a signal output from exceeding a reference voltage from being supplied to an A/D converter at a later stage.

Abstract: Apparatus and method of correcting for dark current in a solid state image sensor, include capturing an image with the image sensor to produce a digital image having pixel values; correcting the pixel values with a dark level correction value; employing a control system to adjust the dark level correction value to drive the number of pixels having values lower than a predetermined value chosen to represent dark scene content to a predetermined range.

Abstract: An imaging device uses a solid state imaging element, during multi-field accumulation to prevent shading and oscillatory phenomena such as repeated black and white patterns. A signal is supplied from a timing signal generation circuit to switches, and controls the ON/OFF operation. During the H period of the signal, the switch is closed, and the output value of an amplifier is input to a capacitor. During the L period of the signal, the switch is opened, and the average value of the output of the amplifier is maintained in the capacitor. During the H period, the switch is open, while during the L period, the switch is in the ON state. At this time, the level of the capacitor C2 and the output of the amplifier are input to an amplifier, and their difference is amplified and supplied to a capacitor C3 via the switch.

Abstract: An image input apparatus has an image sensor for photoelectrically converting image information of an object into an electric signal and outputting the signal, and a correction circuit for adjusting a fluctuation of offset components generated during photoelectric conversion contained in the signal output from the image sensor to correct the offset components. Images of good quality can be obtained by correcting the offset components contained in the signal output from the image sensor.

Abstract: The present invention relates to a CMOS active pixel sensor which includes a compensation circuit capable of compensating a lowered pixel voltage output due to leakage current of a photodiode. The CMOS active pixel sensor having a light sensing unit for generating an output voltage when light is incident thereupon, the sensing unit having an amount of leakage current before the incidence of light. A reset unit resets the output voltage of the light sensing unit to an initial reset voltage in response to a reset signal. A sense transistor has a source, a drain coupled to a power source voltage, and a gate coupled to the output of the light sensing unit. A select transistor has a drain connected to a source of the sense transistor, and provides the voltage of the sense transistor to a bit line, in response to a select signal. A compensation unit supplies a voltage corresponding to the output voltage of the light sensing unit lowered by the leakage current.

Abstract: An image sensing apparatus of this invention includes a signal generator adapted to generate a signal upon reception of input light, a transfer unit adapted to transfer the signal generated by the signal generator, a temperature measuring unit adapted to measure a temperature, an amplification unit adapted to amplify the signal transferred from the transfer unit, and a control unit adapted to control the gain of the amplification unit at a first temperature to be lower that the gain of the amplification unit at a second temperature measuring unit, the second temperature being lower than the first temperature.

Abstract: A method and apparatus for adjusting, on a pixel-by-pixel basis, the gain and offset in an AFE as the pixels are sequentially processed. Although the method can be used for any purpose, it is directed in particular to light source non-linearity, such as edge effects of a scanner. A unique clocking method clocks the gain and offset values into the register at a higher clock rate than the image sampling rate.