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: An image sensor device is provided that has an uncovered imaging array of pixels and a covered global reference non-imaging array of pixels. The pixel samples of the global reference non-imaging array are used to remove noise from the pixel samples of the imaging array. The control signals and control lines that are used to sample the pixels of the imaging array are separate from and independent of the control signals and control lines that are used to sample the pixels of the global reference non-imaging array of pixels. For each row of pixels of the imaging array that is sampled, the same row of pixels of the global reference non-imaging array is sampled. The global reference row has no or very few offsets or variations to ensure that noise removal is performed effectively.

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: 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 is directed to a method and an apparatus for removing noise in an image sensor, more specifically to a method and an apparatus for removing noise caused by a dark current. Through the method for removing noise caused by a dark current that comprises initializing a frame and receiving a digital image signal and converting a value of a clamp bit among bits of the pixel data, included in the digital image signal, to a predetermined value, wherein the clamp bit is a bit stream of sequential digits having a predetermined size comprising a least significant bit among the bits of the pixel data, clearer and shaper images can be displayed through the image sensor.

Abstract: A method for resetting image sensing and an image sensing device using the same are provided. The method for resetting image sensing includes generating a plurality of reset signals and a plurality of control signals, and using the reset signals and the control signals to control a pixel array to reset and expose. The pixel array has a plurality of pixel blocks, each of the pixel blocks has a plurality of pixel sensing units. When the plurality of pixel sensing units of one of the pixel blocks expose to acquire a plurality of sensing signals sequentially, the plurality of pixel sensing units of another one of the pixel blocks are reset.

Abstract: A black level control apparatus and method, particularly for a high-speed video camera (8). The apparatus (10,100) comprises an image signal channel (30,130) for receiving an image signal having a black level from an image sensing device (22,122); a black level sensing device (24,124) for generating a black level signal; a black level signal channel (40,140), independent from the image signal channel, for receiving the black level signal from the black level sensing device; a black level controller (60,160) for receiving an input signal based on the black level signal, measuring a difference between the input signal and a reference signal, generating a control signal based on the difference, outputting the control signal to the image signal channel to adjust the black level of the image signal, and feeding the control signal to the black level signal channel, such that the input signal is based on the black level signal and the control signal.

Abstract: For the purpose of noise correction for an x-ray flat-panel detector (2) it is firstly provided that in the dark image—without radiation impinging on the detector panel (4)—the noise is recorded for the subareas of an active area (8) and from this, subarea-specific correction factors are determined by means of which the respective signal value of the respective subarea is corrected in imaging operation. A dark area correction factor (DF1, DF2) is also determined in each case from the noise of two dark areas (6) that are spaced apart with respect to each other. In order to determine subarea-specific signal correction factors (SK), each of the DA correction factors (DF1, DF2) is weighted with a subarea-specific weighting factor (g1, g2), in particular a distance factor (a). By means of said measure improved noise correction is achieved.

Abstract: A solid state imaging device comprises: photoelectrical converting elements arranged on a semiconductor substrate in a row direction and a column direction substantially perpendicular to each other, wherein charges are accumulated in said photoelectrical converting elements; and a plurality of output sections that output signals corresponding to accumulated charges, said photoelectrical converting elements being arranged in an area that is divided into blocks that correspond to said output sections, wherein said blocks include respective correction areas having a corresponding plurality of sets of correction photoelectrical converting elements used in calculating correction data for correcting output dispersions of said output sections, said correction areas include respective continuous areas that are continuous to each other in a boundary between the plurality of blocks, and an obscuring member, positioned above said continuous areas, that obscures an object image formed in each of said continuous areas.

Abstract: An apparatus for and a method of operating an array of pixels of an image sensor, where each pixel includes at least a photosensor, an associated storage device and a floating diffusion region and the array of pixels is configured in a plurality of rows and columns. The photosensors associated with the pixels are reset and charges are accumulated in the photosensor. The accumulated charges are then globally transferred to storage devices associated with the pixels. A rolling double reset is used to reduce the deleterious effects on the accumulated charges stored in the storage devices. The accumulated charges stored in the storage devices are transferred to floating diffusion regions associated with the pixels and the charges residing in the floating diffusion region are read out. In a second embodiment the storage device is eliminated and the rolling double reset is used to reduce the deleterious effects on the accumulated charges stored in the floating diffusion region.

Abstract: A fixed-pattern noise elimination apparatus 4 eliminates a fixed-pattern noise component resulting from dark current out of an image signal outputted from an effective pixel of a solid-state image sensor 2 during image sensing, by using: a first dark current that is calculated based on a previously acquired signal outputted from a light-shielded pixel of the solid-state image sensor 2 and that is stored in a compensation data memory 6; a second dark current that is calculated based on a previously acquired signal outputted from the effective pixel of the solid-state image sensor 2 with no incident light and that is stored in the compensation data memory 6; and a third dark current that is calculated based on a signal outputted from the light-shielded pixel of the solid-state image sensor 2 during image sensing. With this configuration, a fixed-pattern noise component resulting from dark current can be effectively eliminated irrespective of the temperature of the solid-state image sensor.

Abstract: An imager temperature sensor and a current correction apparatus are provided which use dark pixel measurements from an imager chip during operation together with a fabrication process constant as well as a chip dependent constant to calculate chip temperature. The chip temperature may be used to generate a current correction signal. The correction signal is used to tune a current on the imager chip to correct for temperature variations.

Abstract: An image pickup apparatus includes an image pickup device including a plurality of imaging planes each having different dark current characteristics, and an image processing unit for receiving a signal from the image pickup device and performing an image generating process. The image processing unit calculates a dark current estimated to be generated in each of the plurality of imaging planes, independently for each imaging plane, and performs a dark current eliminating process on the basis of a dark current value calculated for each imaging plane.

Abstract: A circuit and method for correcting pixel output signals for fixed pattern noise. Pixels in a selected row of pixels are read after an integration period and the resulting signals are stored in a first sample and hold circuit for each column. The pixels in the selected row are then reset and immediately read again and the resulting signals are stored in a second sample and hold circuit for each column. The signals in the second sample and hold circuits are subtracted from the signals in the first sample and hold circuits to produce signals related to the light seen by the pixels in the selected row corrected for fixed pattern noise. The output of the first sample and hold circuits and second sample and hold circuits can be connected to a subtraction unit and sequentially activated so that a single subtraction unit is required for the entire imager.

Abstract: An image pickup apparatus for applying high-speed dark shading correction and reducing random noise in a black image is provided. The image pickup apparatus has an image pickup element capable of reading image signals corresponding to one frame, which are obtained by photoelectric conversion, on a field-by-field basis. With the image pickup element exposed to light, first image signals corresponding to one frame are read. Then, with the image pickup element shielded from light, second image signals are read from fields that are fewer than fields constituting one frame. Each of third image signals is generated by averaging the second image signals for each of blocks obtained by dividing the image pickup element and converting the average image signal for each block to a resolution of the first image signals. The third image signals are subtracted from the first image signals.

Abstract: A solid-state image pickup apparatus and an image pickup method are disclosed which can detect and correct fixed pattern noise efficiently and accurately. Pickup image signals produced by reading out signals in parallel from a pixel sensor section are subject to an analog gain process, an A/D conversion process and a digital gain process. Within a period within which the pickup image signals which are based on a fixed value are inputted within a one-frame period, a reference signal average is produced from the signals. Sum values of difference values of the signals from the reference signal average are stored. Within a period within which the pickup image signals from valid pixels are inputted within the one-frame period, fixed pattern noise is removed from the pickup image signals using division averages obtained by dividing the stored sum values.

Abstract: A solid-state image sensor where dark current components fluctuating due to temperature changes are removed from pixel signals without reducing resolution during AD conversion. The sensor has a DA converter for generating a reference signal that increases at a constant slope from a predetermined initial signal level, a comparator for comparing the reference signal with a pixel signal, a counter for performing a counting operation in synchronization with increase in the reference signal, a latch circuit for holding as a quantized value of the pixel signal a discrete value at the time when the reference signal and the pixel signal coincide with each other, an average calculator for calculating an average of the quantized values of pixel signals read out from plural light-shielded pixels, and a reference signal adjuster for setting based on the average the initial signal level of the reference signal compared with the pixel signal read out from a light-receiving pixel.

Abstract: A sensor including an array of sensor elements generates an image responsive to electromagnetic radiation exposure. The sensor reads coordinates for predetermined hot sensor elements and calculates a dark count for each hot sensor element. The sensor determines a temperature indicator based on the dark count for the hot sensor elements and calculates the dark count for all sensor elements based on the temperature indicator. Based on the dark count the sensor is able to compensate for dark current.

Abstract: A signal processing unit or an electronic camera according to the present invention performs signal processing on an output signal from an image pickup part in the order of horizontal shading correction and OB clamp. In the horizontal shading correction, shading correction is also pre-performed on a lateral OB signal serving as a standard of the OB clamp. The OB clamp is performed using the shading-corrected lateral OB signal as a standard, whereby a noise generated due to shading correction can be effectively reduced.

Abstract: A solid-state imaging apparatus including: a pixel section having pixels two-dimensionally arranged into row direction and column direction, each pixel containing a photoelectric conversion section, an accumulation section for accumulating output of the photoelectric conversion section, an amplification section for amplifying output of the photoelectric conversion section accumulated at the accumulation section and outputting it as pixel signal, and a reset section for effecting reset of the accumulation section; a vertical scanning section for selecting row to be read out of the pixel section; vertical signal lines provided correspondingly to columns of the pixel section, onto which pixel signals of pixels arranged in column direction are outputted; a column amplifier section for effecting suppression of dark current component of the pixels contained in pixel signals inputted through the vertical signal line and for amplifying the pixel signals after the suppression; a horizontal scanning section for selecti

Abstract: To provide a solid-state image pickup apparatus with little or no difference in the dark currents between adjacent photoelectroc conversion elements and providing a high sensitivity and a low dark current even in-a high-speed readout operation. A well is formed on a wafer, and diffusion layers are formed in the well to constitute a photodiode. A well contact is formed between the diffusion layers. Element isolation regions are provided between the well contact and the diffusion layers, and conductive layers are provided respectively on the element isolation regions, thereby reducing a difference in the minority carrier diffusions from the well contact to the photodiodes (diffusion layers).

Abstract: An image processing circuit for a color image sensor, comprising a color sensitivity correction circuit which adds/subtracts a predetermined offset to/from pixel signals being output by amplifying photoelectric conversion signals of pixels, which have photoelectric conversion element and are arranged in column and row directions, for each column, and multiplies the result by a predetermined gain, wherein the predetermined offset includes a first offset, which is set according to each color, and a second offset, which is set according to a plurality of columns. According to the present invention, the offset of the color sensitivity correction circuit includes a first offset, which is set according to each color, and a second offset, which is set according to a plurality of columns, therefore, periodic moiré in the vertical direction, which is caused by the column output circuit and the output signal supply circuit for each column, can be suppressed, and image quality can be improved.

Abstract: An imaging system implements digital correlated double sampling (CDS) using dual channels. One channel converts reset voltages from pixel sensors to digital reset values, while the other channel converts integrated voltages from pixel sensors to digital integrated values. Timing of an imaging process with digital CDS can accordingly be the same as the timing for an imaging process without digital CDS, regardless of the length of the exposure time. Accordingly, the imaging time and the frame rate for moving images do not suffer when digital CDS is used to improve image quality.

Abstract: An image capturing system includes a signal correction unit which corrects a signal output from a defective pixel in an optical black region based on a signal output from a normal pixel. The optical black region has a plurality of pixel blocks. Each of the plurality of pixel blocks has a plurality of pixels each including one or more elements which have the same functions as in the remaining pixels and which have relative positions different from the remaining pixels. The signal correction unit corrects the signal output from the defective pixel in the optical black region based on a signal output from a normal pixel which is included in another pixel block different from the pixel block of the defective pixel in the optical black region and includes one or more elements having the same functions and same relative positions as in the defective pixel.

Abstract: A method and apparatus for identifying and compensating for the effects of defective pixels in high resolution digital cameras having image processing apparatus. The apparatus includes a storage system for storing data corresponding to either a dark current reference image and a white reference image and at least one actual image captured by a pixel array, and at least one processor coupled to the storage system for compensating the data corresponding to the actual image based upon the stored data. The method includes capturing and storing both dark and white reference images as well as capturing and storing actual images, identifying pixels that are affected by dark current or are defective pixels, reading data corresponding to pixels of an actual image affected by dark current or that are defective from the storage system and compensating the affected pixels.

Abstract: A number of different elements are added together in a staggered way to avoid the total loss of resolution caused by the binning process. The circuit for doing this includes a variable gain. In a second circuit for carrying this out, to fixed pattern noise reduction circuits are used.

Abstract: A black level correcting device includes: an A/D converting section converting a result of subtracting a feedback signal from an input pixel signal into a pixel value to be output; and a feedback controlling section generating the feedback signal and having a holding section, a feedback gain adjusting section, etc. The holding section clamps a maintaining level to the level of the feedback signal while pixel signals of OB pixels are output, and maintains and outputs the maintaining level while pixel signals of valid pixels are output. The feedback gain adjusting section multiplies the feedback signal by clamp accelerating gain in synchronization with starting readout of the pixel signals from the OB pixels. Accordingly, clamp time of the holding section is shortened, enabling stabilization of the maintaining level at a convergence level before starting readout of the pixel signals from the valid pixels. Consequently, a sag can be reduced.

Abstract: Disclosed embodiments provide methods and apparatuses for dark current compensation of imager pixels signals. A row-wise dark offset is calculated and then subtracted from the imaging pixel signals, a row-wise dark offset for at least one row being different from a row-wise dark offset for at least another row.

Abstract: An image sensor comprises an active pixel region that includes a plurality of unit pixels arranged in a matrix pattern, a first optical black region formed adjacent to the active pixel region, wherein a plurality of shaded unit pixels are arranged therein, a drain region formed adjacent to the first optical black region, the drain region discharging excess electrons generated in the active pixel region, and a second optical black region formed adjacent to the drain region, wherein another plurality of the shaded unit pixels are arranged therein.

Abstract: An apparatus for and a method of operating an array of pixels of an image sensor, where each pixel includes at least a photosensor, an associated storage device and a floating diffusion region and the array of pixels is configured in a plurality of rows and columns. The photosensors associated with the pixels are reset and charges are accumulated in the photosensor. The accumulated charges are then globally transferred to storage devices associated with the pixels. A rolling double reset is used to reduce the deleterious effects on the accumulated charges stored in the storage devices. The accumulated charges stored in the storage devices are transferred to floating diffusion regions associated with the pixels and the charges residing in the floating diffusion region are read out. In a second embodiment the storage device is eliminated and the rolling double reset is used to reduce the deleterious effects on the accumulated charges stored in the floating diffusion region.

Abstract: A pixel structure includes two different photosensitive portions. One portion is shielded from incident light and the signals from both are fed into an op amp so that the differential signal is output as the pixel output, thereby cancelling dark current.

Abstract: A black clamp circuit for an image sensor utilizes a differential programmable gain amplifier and a feed-back loop to adjust a black level based on comparison to a reference black level. The gain (and therefore step size and range) of the feed-back loop constant for all programmable gain amplifier gain settings. The gain of the fee-back loop is kept constant by adjusting the values of programmable capacitors in the circuit.

Abstract: A method and apparatus for forming dummy pixels exhibiting electrical characteristics virtually identical to the clear pixels of the imaging array. Arrays of such dummy pixels are used to form regions that isolate the main imaging array and sub-arrays of optical black pixels while preventing edge effects. The dummy pixels are preferably clear but can also be covered with optical black. By setting quiescent operation in soft reset, the dummy pixels exhibit the diode ideality and RoA product that are typical of any of the pixels in the entire array.

Abstract: The invention relates to a technique removing a dark voltage noise signal occurring at the time of light shielding of a photoelectric conversion device, simplifying the system configuration such that the cost and occupying area is reduced, and suppressing variation among a plurality of buffer amplifiers.

Abstract: A method of performing dark correction for signals generated by an image sensor is disclosed. Dark state signals are received from an image sensor and a dark correction ratio is determined for each pixel based on the dark state signals. Operational state signals are received from the image sensor and a pseudo dark signal is determined for each pixel based on the dark correction ratio and further based on the operational state signals. A corrected signal value based on the pseudo dark signal is determined. The method is capable of compensating for dark signals from the image sensor over a course of a series of measurements notwithstanding changes in temperature and exposure time.

Abstract: A digital clamping circuit and a digital clamping method are provided which can effectively use the dynamic range of an output signal in black-level correction. When subtracting a black level serving as a reference value from an output signal of an analog front end circuit, a digital clamp circuit permits the production of a negative value, amplifies the dynamic range including the-negative value to increase the dynamic range, adds a predetermined value to the resulting signal, and performs clipping. As a result, the dynamic range of the digital clamp circuit is increased, so that the dynamic range of an output signal can be effectively utilized. Thus, processing that makes good use of a wider dynamic range can be performed in image processing at a subsequent stage, so that image quality can be improved.

Abstract: An image sensing system includes an image sensor and a black clamping circuit which reside on the same substrate. Particular embodiments use common components for both imaging and black clamping, and digital control of an analog black clamp function.

Abstract: An active pixel sensor array sampling system includes a plurality of video circuits and reset circuits. A video circuit generates a video voltage from each one of the pixels of a column of pixels. An associated reset circuit generates a reset voltage for each of the pixels of a column of pixels. The video circuits and the reset circuits are closed loop sample and hold circuits. The active pixel sensor array is integrated on an integrated circuit.

Abstract: The present invention is directed to a method and an apparatus for compensating for a black level of an image sensor. The apparatus for compensating for a black level comprises: an optical black area detecting unit, detecting a pixel located in an optical black area, the pixel being among a digital image signal received from the sensor unit; a pixel data analyzing unit, summing pixel data of the pixel detected by the optical black area detecting unit to a pixel data sum; and a compensated data generating unit, generating compensated pixel data corresponding to the pixel data through a matching graph generated using a normalized value. With the present invention, the black level caused by a dark current can be compensated, and the noise caused by a dark current can be removed, while maintaining the dynamic range.

Abstract: An apparatus for providing amplified image data may include an image sensor including a number of pixel light sensing elements. Circuitry may output pixel exposure signals and a dark level signal. The differences between the pixel exposure signals and the dark level signal are uni-polar signals. A variable gain amplifier may shift the uni-polar signals to bipolar signals centered around zero, and may also amplify the bipolar signals. In this manner, a full scale output range of the variable gain amplifier may be substantially utilized.

Abstract: A photographing apparatus includes: a photographing unit having an image pickup device, the photographing unit carrying out first photographing for obtaining a first image with the image pickup device being set in an exposure state, and second photographing for obtaining a second image with the image pickup device being set in a light-shielded state; a correcting unit for correcting the first image based on the second image to obtain a corrected image; and a photographing controlling unit for controlling priorities between new first photographing and the second photographing if an instruction for carrying out the new first photographing is given during the second photographing.

Abstract: An image capturing apparatus includes an image sensor which photo-electrically converts an object image formed by an objective lens, a shutter which is arranged between the objective lens and the image sensor, opens to set the image sensor in an exposure enable state, and closes to set the image sensor in a light-shielding state, a dark image acquisition unit which acquires a dark image by closing the shutter and causing the image sensor to accumulate charges, and a control unit which controls an aperture size of an aperture stop arranged at the objective lens, wherein if the aperture stop has a aperture size more than a predetermined aperture size before acquiring the dark image, the dark image acquisition unit acquires the dark image after the control unit controls the aperture stop to an aperture size not more than the predetermined aperture size.

Abstract: A method and apparatus are described that detect and correct for over-saturation lighting conditions in a CMOS Image Sensor.

Abstract: A method to reduce the effect of noise on a pixel sensor element includes accumulating charge during an image capture operation (the accumulated charge representing a combination of noise and image), and discharging the accumulated charge for a predetermined time to generate a pixel sensor signal. The act of discharging may be passive or active.

Abstract: For each current image output from a pixel matrix, the digital words relative to at least one masked line of the matrix are processed to generate a current correction digital code. From this code, a black level compensation signal is generated and applied as an offset control on pixel signal amplification. If the current correct digital code does not differ from the code calculated for a previous image output by a predetermined amount, then the code for the previous image is instead used to generate the black level compensation signal.

Abstract: An object of the present invention is to provide an imaging device which can reliably correct dark current components that locally occur in an imaging sensor, such as those caused by an FDA. The imaging device includes: a storage unit which pre-stores information representing a relation between one of dark current components and an output signal of an optical black pixel arranged in a predetermined optical black area on an imaging sensor, the dark current components being superimposed on pixel signals of effective pixels, respectively, arranged in a predetermined effective pixel area on the imaging sensor; a dark current obtaining unit which obtains dark current components based on both the information stored in the storage unit and output signal of the optical black pixel; and a correcting unit which corrects the dark current components obtained by the dark current obtaining unit according to the pixel signals.

Abstract: An active pixel sensor array sampling system includes a plurality of video circuits and reset circuits. A video circuit generates a video voltage from each one of the pixels of a column of pixels. An associated reset circuit generates a reset voltage for each of the pixels of a column of pixels. The video circuits and the reset circuits are closed loop sample and hold circuits. The active pixel sensor array is integrated on an integrated circuit.

Abstract: An apparatus and method that reduces the dark current in each pixel of an image sensor, where each pixel has a pinned photodiode. A negative potential barrier at the transfer gate of each pixel is raised when the photodiode is integrating (when the transfer gate is “off”) to thereby eliminate dark current generation in this region. The potential barrier is applied via a “triple well” transistor circuit structure that is capable of handling a strongly negative voltage. The circuit structure also serves as a conduit for conducting a strongly positive voltage to minimize the potential barrier during signal transfer and readout, thereby reducing image lag.

Abstract: The present invention relates to a method for determining the reference image of an image sensor comprising a matrix of detector pixels. The method comprises the acquisition of a black image IN and two images I1 and I2 acquired in linear detection zones of the sensor. The reference image is written: IR1=(Rm* I1?I2)/(Rm?1) with I R ? ? 1 = ( R m × I 1 - I 2 ) / ( R m - 1 ) ? with ? ? Rm = 1 N ? ? i , j ? I 2 ? ( i , j ) - I N ? ( i , j ) I 1 ? ( i , j ) - I N ? ( i , j ) , wherein IK (i,j) represents the value of the pixel of the image IK detected by the pixel detector situated at the intersection of the row i and the column j of the detector pixel matrix, and N represents the total number of pixels in the matrix.

Abstract: A digital camera includes a solid-state imaging device in which plural pixel columns, each including plural pixels arrayed in a column direction, are arrayed in a row direction. The pixels of each pixel column include upper OBs, lower OBs, and PDs disposed between the upper OBs and the lower OBs. The digital camera includes: a dark current correcting unit that performs dark current correction based on a linear function for correction in order to correct a dark current; an OB average calculating unit that calculates an average of upper OB signals acquired from the upper OBs by imaging and an average of lower OB signals acquired from the lower OBs by the imaging; and a correcting linear function generating unit that generates the linear function for correction based on the average of the upper OB signals, the average of the lower OB signals, and the number of PDs.