Abstract: An image sensor includes an active pixel area for image capture; one or more black pixel areas disposed in a pre-determined, significant spaced apart distance from the active pixel area; and a light shield to prevent light from illuminating the black pixel areas.

Abstract: When storage time has changed during a continuous shooting operation, the storage times are stored. When the continuous shooting operation has been completed or an available capacity of a storage medium has become lower than image data, the data is imaged with the respective storage times without exposure. The exposed image data is processed on the basis of the data acquired by the charge storage of an image pickup device without exposure.

Abstract: An aspect ratio variable solid state imaging device capable of reducing the frequency of a drive pulse of a horizontal register required for discharging signal charges in unnecessary portions at a small aspect ratio or of reducing a discharge period for signal charges in unnecessary portions in each horizontal period. In the mode of a small aspect ratio, in the horizontal blanking period, signal charges in the right side unnecessary portion on one line is mixed with signal charges in the right side unnecessary portion for the next line at the output end section of the horizontal register, and then the mixed signal charges are transferred to be discharged in the horizontal blanking period. In the horizontal transfer period, signal charges in the middle portion is horizontally transferred.

Abstract: A solid-state image sensor comprising an effective pixel area having light receiving portions which perform photoelectric conversion by taking in light and an optical black area which forms a reference black level without taking in light. The light receiving portions are formed inside electrode opening port portions which are formed through an electrode. Electrode opening port portions in the optical black area which are formed through the electrode are formed narrower than the electrode port portions in the effective pixel area. Alternatively, there may be no opening port portions formed in the optical black area.

Abstract: A method of minimizing noise in an image produced by an electronic imager comprising: determining a correction system for a range of imager integration times and a range of imager temperatures for an electronic imager which has taken a series of dark capture images and a series of flat field capture images in a calibration mode; and applying the correction system to an image produced by the electronic imager in an image capture mode.

Abstract: A solid state imag pickup device included light-receiving circuitry having a plurality of light-receiving cells arranged in a matrix. Apparatus is provided for reading and storing electrical signals output by the light-receiving circuitry, and includes (1) a first memory for reading bright signals out of the light-receiving cells arranged in a row for storing the bright signals for a horizontal scanning period, (2) a second memory for reading dark signals out of the light-receiving cells arranged in the row for storing the dark signal for the horizontal scanning period, and (3) a readout circuit for reading the bright and dark signals stored in the first and second memories simultaneously. A removing circuit is provided for removing fixed pattern noise by simultaneously processing the bright and dark current signals read out from the first and second memories. Preferably, this removing circuit comprises a differential amplifier.

Abstract: An optical black portion in an output of a CCD image pickup device is extracted and a clamp level of each line is obtained by an integrating and averaging circuit. A difference value of the clamp levels between the front and rear lines and an absolute value of the difference are calculated by a comparing circuit. Either the clamp level of each line or the clamp level updated every (+1) or (−1) is selected by a selector in accordance with whether the absolute value of the difference of the clamp levels between the front and rear lines lies within a predetermined range or not. The clamp level which is outputted from the selector is subtracted from the output of the CCD image pickup device.

Abstract: An image pickup apparatus having a function for OB clamping, the image pickup apparatus including an XY addressing type solid-state image pickup device having light receiving pixels and optically shielded OB pixels on the periphery of the light receiving pixels and drive means for driving the solid-state image pickup device in both or one of a thinned-out readout mode for reading out one light receiving pixel out of every given number of pixels and a mode of reading out the light receiving pixels in a given region, wherein OB clamping is effected by always reading out OB pixels at the same location, regardless of the above two signal readout modes or regardless of location and/or number of light receiving pixels to be read out in the above two signal readout modes. A stable OB clamping is thereby effected even when there has been a change in signal readout mode or in location and/or number of pixels to be read out.

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: There is disclosed an image sensor wherein the dispersion in threshold voltages of a transistor constituting a source follower for outputting a signal is compensated. The disclosed image sensor is provided with a coupling capacitor to which an output voltage of a pixel is applied through a transistor and with a transistor of a source follower to read out a voltage at the node S/Hn of the coupling capacitor.

Abstract: An imaging system that uses an array controller which is adapted to imaging arrays having black cells to control an imaging array not having black cells. The imaging system includes an array controller that is adapted to process a scan line that includes one or more black pixels. The imaging system includes an imaging array not having black cells that generates a series of pixel data samples in response to light from an image. The imaging system includes circuitry for generating the scan line by synthesizing the black level pixels and combining the black pixels with the series of pixel data samples.

Abstract: Switches SHS and RSM are turned on to hold an image signal at a negative electrode of a capacitor Cs, then a switch SHN is turned on to hold a noise signal at a positive electrode of a capacitor Cn. Then a switch RSP is turned on and then a switch MIX is turned on to combine together the image and noise signals thus held and thereby produce, as a voltage signal, a noise-free image signal at the node between the capacitor Cs and the switch MIX. Then a switch Sx is turned on to output the noise-free image signal.

Abstract: A system and related method for compensating for dark current in an image capture device is disclosed. An embodiment of the invention includes an image sensor for capturing a dark image, a memory element for storing the dark image, and logic for assigning a mathematical function to the dark image, where the only variable in the mathematical function is time. The image sensor captures an image, the image including a time of capture indicator, where the time of capture indicator is assigned to the mathematical function. The invention then calculates a dark current value at the time of image capture and subtracts the dark current value from the captured image.

Abstract: An image sensor comprises a plurality of pixel sensors, e.g., CMOS pixel sensors, including a plurality of dark pixels. A dark level compensation circuit that controls an offset applied to an image signal generated by a pixel sensor responsive to an aggregate dark level metric, e.g., a mean dark level, derived from dark pixel image signals produced by the dark pixel sensors. For example, the dark level compensation circuit for CMOS image sensor using a column parallel architecture may generate an offset control signal that varies an offset of a reference signal used by an analog to digital converter (ADC) circuit that converts an analog image signal from a pixel sensor to a dark level compensated digital image signal.

Abstract: In a solid state image device which has at least a horizontal CCD register, the horizontal CCD register is covered with a light shielding film which is formed by a resin material.

Abstract: Two methods for suppressing the fixed pattern noise effects of a pixel reset switch by ensuring that the reset NMOS device operates in its linear region. The first approach uses a separate reset switch supply voltage, VRES, set to at least one threshold voltage below the sensing switch supply voltage, Vdd. The second approach uses a charge pump and level shifter to push the reset gate voltage at least one threshold voltage higher than a supply voltage common to both the reset and sense transistors.

Abstract: There has been raised a problem of how to make the measurement of characteristics of a solid state image pickup device easy to carry out, to shorten the measurement time and to increase the measurement accuracy. In order to solve the problem described above, the solid state image pickup device is operated to generate an output with an operating condition for an odd field made different from that for an even field. For example, a dark signal can be detected with the supply of read pulses for either odd or even fields halted typically at the same time as a playback signal is detected in a state of being shielded from light or a state of applying an incident light with a predetermined quantity. As a result, it is possible not only to measure a variety of characteristics merely under a plurality of conditions at the same time but also to further process outputs of the odd and even fields in order to measure still another characteristic such as a dark current generated by an image pickup area.

Abstract: Image signals used in a camera from a CCD are sampled-and-held by a CDS circuit, subjected to an A/D conversion, stored in a DRAM, and stored in a recording medium after a compression process of data from an effective area and an optical black area of the CCD by a compressing/decompressing circuit. Image output is regenerating by decompressing the compressed data in the recording medium. A margin area is defined at a boundary area of the effective area and the OB area and the output from the margin area is not used for image data processing, so that noise does not affect the image output. In this camera, high quality image signals can be obtained and a black level can be accurately corrected.

Abstract: A clamping circuit of a solid-state imaging apparatus for receiving a pixel signal including a black level and a signal level through a signal line and outputting the pixel signal with noise being suppressed, the clamping circuit includes: a first capacitance and an inverting amplifier inserted into the signal line and connected to each other in series; a first switch and a second switch connected to each other in series to form a serial circuit; and a second capacitance connected between the first and second switches of the serial circuit and a constant potential, wherein both sides of the serial circuit including the first switch and the second switch are connected to an input side and an output side of the inverting amplifier, respectively; the first switch and the second switch are opened and closed in synchronization with a clock signal; and a time constant defined by an output-side impedance of the inverting amplifier and the second capacitance when the first switch and the second switch are closed is s

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: A correction circuit 50 is provided to correct the luminance shading caused by uneven thickness of the liquid crystal layer in the LCD panel. The correction circuit 50 generates a correction signal obtained by modulating the gradually changing signal with smaller amplitude at positions closer to the center in the horizontal direction of the LCD panel and with smaller amplitude at positions closer to the center in the vertical direction when the signal is seen vertically. The signal in the lowfrequency range components of the video signal is used for such modulation. After addind the correction signal from the correction circuit 50 to the video signal by the adder 51, the signal is processed for AC driving and then supplied to the LCD panel section 10. By thus superimposing the correction signal on the video signal for the LCD panel, the luminance shading can be corrected.

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: 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: Solid-state image-pickup devices and associated drive methods are disclosed that simultaneously provide an image signal and a motion-detection signal. A representative device comprises an array of multiple pixels that produce pixel outputs according to amounts of light received by individual pixels. A vertical-readout line is provided for each column of pixels. A vertical-scanning circuit sequentially outputs signals from the pixels to the vertical-readout lines in horizontal-line units. Differential-processing circuits subtract out dark signals from image signals. Body-motion-detection circuits output a signal based on the difference between the pixel outputs during a current frame and the pixel outputs during a previous frame. A horizontal-scanning circuit sequentially delivers the outputs of the differential-processing circuits and the body-motion-detection circuits onto respective horizontal-readout lines to simultaneously form an image signal and motion-detection signal.

Abstract: A correlated double sampler (CDS) circuit having a ping/pong architecture which employs only a single amplifier, and a CCD image sensor output processing circuit including such a CDS circuit and preferably also an analog-to-digital converter for processing the output of the CDS circuit and a black level correction feedback loop. In one cycle of operation (during processing of the raw output of a CCD sensor), the CDS circuit receives a first set of control signals followed by a second set of control signals, its output signal in response to the first set is indicative of the value of one pixel of a sensed image, and its output signal in response to the second set is indicative of the value of the next pixel of the image. Preferably, each set of control signals consists of a clamp signal, a sample signal, and a hold signal.

Abstract: An analog signal processing apparatus for a digital camera includes a correlated double sampling (CDS) circuit adjusting a direct current (DC) level signal from a charge coupled device (CCD) by using a black level as a reference and converting the DC level signal into a typical video signal, an automatic gain control (AGC) circuit automatically adjusting the gain of an output signal of the CDS circuit, an analog-to-digital (A/D) converter converting the analog signal from the AGC circuit into a digital image signal, a black level clamp circuit clamping the black level of the digital image signal from the A/D converter for a predetermined time interval and feeding back the clamped black level to the CDS circuit, and a clock generator generating first and second clock signals and a black level clamping signal so as to control the timing of the black level clamp circuit.

Abstract: A digital camera is incorporated into a mobile telephone handset. An image window, used as a viewfinder, includes an indicator in the form of a three-part bar for showing whether an optimal image can be captured. Exposure, white balance and dark reference are determined using algorithms executed by the handset.

Abstract: A method includes generating a noise frame of data that is representative of a dark current image. Video frames of data are generated that represent video images. The video frames include noise. Information from the noise frame is used to compensate for the noise.

Abstract: An imaging apparatus and a method of capturing and storing an image in digital form within a photosensitive area of the apparatus include integrating an array of memory cells within each pixel of the photosensitive area. Preferably, the memory cells are dual port memory cells, such that write operations can be performed in a parallel manner while reading operations are performed in a serial manner. In the preferred embodiment, each array contains a sufficient number of memory cells to store two digital words representing a photo signal and a reference signal. A comparator within each pixel operating in unison with a counter and a ramp generator captures the photo signal and the reference signal in digital form. The design of the imaging apparatus allows each pixel in the photosensitive area to capture and store the signals in a parallel manner.

Abstract: A correlated double sampled/programmable gain amplifier (CDS/PGA) is disclosed which is operable to precondition a CCD output analog signal. The CDS/PGA includes an operational amplifier that is configured in a sample hold operation. The single-ended input is first clamped by a switch (34) to clamp the DC level therein for a given pixel. A switch (38) then samples the reset level onto a sampling capacitor (46), and a switch (42) thereafter samples the video signal onto one plate of a capacitor (50). The lower plates of the capacitors (46) and (50) are then equalized and the other plates thereof connected to the positive and negative inputs of the operational amplifier (68). An offset is provided by a programmable DAC (26) to account for the dark current offset. The output scale is adjusted or mapped by limiting the output between a negative and a positive reference input. The sampling capacitors (46) and (50) can be varied to vary the gain of the amplifier.

Abstract: An imaging device includes a compensation circuit for reducing an effect of dark current generated during operation. The compensation circuit calculates an initial dark current offset value using optically dark regions of a photo sensitive array. The compensation circuit also automatically adjusts the initial dark current offset value as output signals from successive rows of the photo sensitive array are transferred. The compensation circuit can calculate the initial dark current offset value each time an image is captured, thereby compensating for variables such as temperature.

Abstract: A method of compensating for nonuniformities in an image sensor includes: providing an image sensing device 20; measuring test pixel signals from the image sensing device 20 during a test mode; determining which test pixel signals are greater than a fixed threshold level ST; and calculating nonuniformity coefficients for the pixels having test pixel signals greater than the fixed threshold level ST.

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 is generally supplied to an A/D converter as 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 âH1 and âH2 of a signal output by an empty transmission unit 13a by means of a clamp pulse âCLP1 and a sample/hold output Va for the second picture element or a subsequent one of an OPB unit 11a is clamped to a clamp level Vref by means of a clamp pulse âCLP2 so as to prevent a signal output Vout exceeding a reference voltage from being supplied to an A/D converter at a later stage.

Abstract: A circuit for determining the median dark level of an image sensor, the circuit comprises a first circuit for comparing a current pixel value and a cumulative median; a storage element for storing the cumulative median level; and a second circuit which utilizes the first circuit for adjusting the cumulative median based on the current pixel level input for updating the cumulative median dark level.

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: An image pickup apparatus including: CCD image pickup device; a light blocking plate for shutting out light incident upon the image pickup device; an exposure period controlling section for setting exposure time by controlling the light blocking plate and the image pickup device; a dark signal storing section for storing dark signals obtained from the image pickup device in a state where light is shut out by the light blocking plate; a subtracting section for subtracting the dark signals from main image pickup signals of the image pickup device; a defect detecting section for detecting defects from the subtracted image pickup signals outputted from the subtracting section; and a defect correcting section for performing correction of the detected fault pixels.

Abstract: A method for dark current subtraction which enables a dark frame to be reused for dark current subtraction for multiple image frames. The dark frame is reused by scaling it according to changes in the dark current levels associated with the dark frame and the image frames.

Abstract: A solid state image pickup device includes light-receiving circuitry having a plurality of light-receiving cells arranged in a matrix. Apparatus is provided for reading and storing electrical signals output by the light-receiving circuitry, and includes (1) a first memory for reading bright signals out of the light-receiving cells arranged in a row for storing the bright signals for a horizontal scanning period, (2) a second memory for reading dark signals out of the light-receiving cells arranged in the row for storing the dark signal for the horizontal scanning period, and (3) a readout circuit for reading the bright and dark signals stored in the first and second memories simultaneously. A removing circuit is provided for removing fixed pattern noise by simultaneously processing the bright and dark current signals read out from the first and second memories. Preferably, this removing circuit comprises a differential amplifier.

Abstract: An imaging device having an in vivo CMOS image sensor, at least one illumination source and a controller. The controller controls the illumination source to illuminate for a first period and to be shut off for a subsequent period.

Abstract: A random access memory stores values indicative of fixed pattern noise from a pixel circuit, which are used to compensate the pixel output to compensate for the fixed pattern noise.

Abstract: The invention provides a system for recording and displaying a time sequential scene on a computer (16). The digital camera (12) transmits a sequence of digital image frames to the timer (14) representative of the image of a body passing a plane in space. Each frame represents a line object (18) of the body, thus forming a fractional part of the scene. Once the frame reaches the image timer (14), it is digitally marked with a time reference (34) and buffered into a block of information. The main control computer (16) stores blocks of information from the image timer (14) for a variety of processing and features available to the user. The invention also provides a selected memory (36), preferably a virtual memory subsystem, or hard-disc drive. Preferred constructions for adjusting camera pixel processing of light values, time-marking the images, creating color palettes for interactive viewing of color images, and video data coding to accommodate the high volume of line image data are described.

Abstract: A system for automatic color calibration for a color display is provided having an assembly of a member adjacent the outer periphery of the screen of the display and a color measuring instrument coupled to the member. The system is particularly usefull at a site or node of a network of sites or nodes for distributing and controlling color reproduction. The color measuring instrument includes a sensor spaced from the screen at an angle with respect to the screen for receiving light from an area of the screen. Methods are also provided for maintaining calibration of a color display using a color measuring instrument. Apparatuses are further provided for checking the calibration of a color measurement instrument having a spectrograph for measuring color.

Abstract: In a photosensitive device wherein voltages are read sequentially from a dark, or dummy, photosensor and a plurality of active photosensors with each of a series of scans, a circuit downstream of the photosensors resets the offset value of the voltage signals, based on successive voltage readings from the dark photosensor. An RC averaging circuit maintains a running average of readings from the dark photosensor over a large number of scans. Signals from the dark photosensors are read a first time into the averaging circuit, and then signals from the dark photosensors are read directly to downstream video circuitry. This double readout of dark-photosensor signals enables precise calibration of both on-chip circuitry and downstream video circuitry.

Abstract: An image-sensor emulating device establishing a link with a host system by using peripheral interface bus. The image-sensor emulating device emulates the functions of image-sensors by programmably generating the relevant image-sensor and timing signals. Alternatively, the timing signals can also be generated from the timing signals outputted by an outside image-sensor. Therefore, the emulating device can generate predetermined image-sensor signals and timing signals such that the debugging process is simplified and the developing efficiency is improved. Moreover, the emulating device according to the present invention can also generate a timing signal serving as a reference timing signal for emulating an image-sensor. The reference timing signal can be used to compare with the actual timing signals of an image-sensor.

Abstract: An image sensor array for capturing a sequence of video frames has a plurality of pixels, wherein each one of the pixels has a set of intrapixel logic including a previous register to store a pixel value of a previous frame and a current register to store a pixel value of a current frame, the current registers corresponding to the previous registers. An intrapixel subtractor coupled to the previous and current registers produces a difference between the previous and current registers for all pixels in the video frames in parallel. The differences are accumulated for each block of the image sensor array to form a total divergence for each block. The total divergences, associated motion vectors, and pixel values are used in motion estimation processing by a processor coupled to the image sensor array.

Abstract: The present invention relates to a HCCD of a CCD image sensor comprising a channel stop region, a BCCD channel formed on the channel stop region, a plurality of first poly gates and a plurality of second poly gates formed on the BCCD channel and alternately arranged in a partially overlapping manner, and a dummy gate formed on the BCCD channel between first and second selected ones of the second poly gates.

Abstract: An image processing apparatus (200) for a charge coupled device including analog front end circuitry having optical black and offset correction, whereby the offset and optical black correction circuit is programmable. The present invention includes a first circuit (202, 204, 206, 208, 210) to sample the incoming optical black signal output from a CCD. This first circuit includes a correlated double sampler (202) coupled to a first programmable gain amplifier (204). An adder (206) connects between the first programmable gain amplifier (204) and a second gain amplifier (208) for adding in the optical black offset to the optical black signal input from the CCD. A second circuit (212, 214) includes a reverse programmable gain amplifier (212) connected to the output of the second programmable gain amplifier (208) to amplify the optical black level inversely proportional to the gain from the second programmable gain amplifier (208).

Abstract: A method for controlling the exposure of an active pixel array electronic still camera includes the steps of: integrating photocurrent in each pixel during an integration time period; collecting overflow charge from all pixels in the array during the integration time period; developing an overflow signal as a function of the overflow charge; and terminating the integration time period when the overflow signal exceeds a preset threshold level selected to represent a desired reference exposure level.

Abstract: In an imaging apparatus for detecting a dark output level superposed on an imaging signal which is an output signal of an imaging device and correcting the imaging signal based on the detected dark output level, occurrence of a false signal caused by the dark output correction process is prevented and a substantial lowering in the effective imaging range is prevented by eliminating a dark output component from the imaging signal and setting a clip level and gain for a subject signal component according to the detected dark output level.

Abstract: Disclosed is an image sensing apparatus having a function of removing a dark current noise component of an image sensor. This image sensing apparatus includes an image sensor such as a CCD, at least two noise component storage areas, a CPU for controlling an operation of writing a noise component of one frame generated by the image sensor into a noise component storage area selected from the at least two noise component storage areas, and a subtracter for correcting an object image photographed by the image sensor, on the basis of the noise component stored in one of the at least two noise component storage areas.