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: Provided is a solid-state imaging device including a plurality of vertical transfer units (VCCDs), a horizontal transfer unit (HCCD) and a driving unit.

Abstract: Disclosed herein is an imaging apparatus including: a pixel section having a plurality of pixels arranged in two dimensions for effecting photoelectric conversion; a light blocking section for blocking light to conceal the pixel section in accordance with a light blocking instruction signal; a region setting section for outputting the light blocking instruction signal and setting a correcting pixel region from which pixel data for correction are extracted within an effective pixel region of the pixel section where an object image is formed; a line memory for retaining pixel data from the correcting pixel region at the time of blocking light; and a correcting section for correcting an output of pixel data from the pixel section using the pixel data retained at the line memory.

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.

Abstract: It is intended to obtain a high quality image which is not affected by the fluctuation of dark outputs, and pixels having a specifically large dark output, called defects, and has no lateral line etc. A solid-state image pickup apparatus including: an aperture pixel region which accumulates and outputs the electric charges generated depending on incident light; a light shielded optical black region; a black reference pixel region in which no impurity region for accumulating electric charges is formed; and level shifting means which shifts the reference level of the output signals of the black reference pixel region with respect to the reference levels of the output signals of the aperture pixel region and the optical black region, is provided.

Abstract: According to this invention, even when an image capturing apparatus has a plurality of read modes, the frame rate can be prevented from decreasing in a high-resolution video photographing mode. The image capturing apparatus includes an image sensor and drive unit. The image sensor includes an effective image sensing area having a plurality of pixels at the center portion of the image sensor, and a light-shielded pixel area having a plurality of light-shielded pixels at the peripheral portion of the image sensor. The drive unit can drive the image sensor in a plurality of modes, and drives the image sensor such that the plurality of read modes are almost equal to the light-shielded pixel read time BL-MIN for reading pixel signals in the light-shielded pixel area.

Abstract: A digital still camera records image data by picking up an image of an object. One mode is set among plural photographing modes including a standard photographing mode and a portrait mode adapted to an image containing an abrupt change in gradation. An optimized exposure amount is acquired according to brightness derived from the image data. When the portrait mode is set, portrait mode image data is acquired by setting exposure lower than the optimized exposure amount. The image data is processed in gradation conversion by use of first or second gamma conversion table. The first gamma conversion table is used for the standard photographing mode. The second gamma conversion table is used for the portrait mode, predetermined to extend a dynamic range of the image data after the gradation conversion in comparison with the first gamma conversion table, to process the portrait mode image data in gradation conversion.

Abstract: A signal detecting system for reading a charge signal from an image recording medium includes a signal storing circuit, a first low-pass filter into which the charge signals stored in the signal storing circuit are input, a first sample hold circuit which sample-holds the charge signal passing through the first low-pass filter, a second low-pass filter into which the charge signals stored in the signal storing circuit are input, a second sample hold circuit which sample-holds a reference level signal when the input of the charge signal passing through the second low-pass filter is at a reference potential, a difference circuit which outputs as an image signal the difference between the charge signal and the reference level signal, and a controller which controls the initiating timings of the sample hold circuits so that the initiating timing of the first sample hold circuit is earlier than that of the other.

Abstract: A conventional image sensor has a narrow dynamic range, so that the conventional image sensor has the limitation of not representing very dark portions or very bright portions depending on the exposure time when representing an image having such dark and bright portions. The present invention provides an image sensor including at least two storage units for respectively storing at least two image signals; a first switch unit for performing switching applied image signals to be respectively stored in the at least two storage units; and a second switch unit respectively connected to the at least two storage units and for equalizing the image signals stored in the at least two storage units.

Abstract: A fixed pattern noise of an image converter is automatically determined. A first optical image is converted using the image converter into digital image data, the light level of the first optical image is determined, the light level of the first optical image is compared with a threshold value, and the image converter characteristics of the image converter are reset to a dark image setting in such a way that the image data generated over the photosensitive imaging surface of the image converter at constant distribution of the determined light level include no component produced by the light level. Immediately thereafter, using the dark image setting previously set, a first dark image is recorded.

Abstract: After an end of exposure, a data level of OB signals that are imaging signals output from OB portion 400 are sampled by a CDS circuit 6 twice, to artificially generate two OB signals from each OB signal. Thereby, assuming that the total number of OB signals required to stabilize the black level in the clamp circuit 9 is n, the black level can be stabilized before it is started to output effective signals that are imaging signals from effective pixel portion 200 even if the number of OB signals output from the OB portion 400 is 1/n (in the case where pixel mixing or pixel thinning is performed, or in the case where the number of photoelectric conversion elements in the OB portion 400 is less than n). Accordingly, it is possible to prevent the image degradation by suppressing a wrong black level.

Abstract: An apparatus and a method for efficiently executing correction of false color, such as purple fringe, caused by chromatic aberration and for generating and outputting high-quality image data are provided. A white-saturated pixel is detected from image data, a false-color-pixel detection area is set around the detected white-saturated pixel, and pixels having color corresponding to false color such as purple fringe are detected from the set area. The detected pixels are determined as false-color pixels and correction processing based on the values of the surrounding pixels is performed on the determined false-color pixels. With this configuration, an area of false color such as purple fringe generated in the neighborhood of a white-saturated pixel can be efficiently detected, pixel values can be partially corrected, and high-quality image data can be generated and output without affecting the entire image.

Abstract: A system and method of capturing an acceptable fingerprint image is disclosed herein. The method includes a step of capturing an initial fingerprint image at a nominal image integration time. Once this initial fingerprint image is captured, a first intermediate fingerprint image at a first intermediate image integration time is captured. Next, an image darkness test is performed followed by an image definition test. If one or more of these tests indicates that the first intermediate fingerprint image is unacceptable, a subsequent intermediate fingerprint image at a subsequent intermediate image integration time is captured. This subsequent intermediate fingerprint image can be captured before the image definition test is performed. Additional intermediate fingerprint images can be captured until an image that has an acceptable darkness level as a well as an acceptable definition level is captured. Also disclosed is a fingerprint scanner that performs this method.

Abstract: An image processing apparatus includes an optical system having distortion aberration characteristics for expanding a central part and compressing a peripheral part of an image plane; an image sensor for photodetecting an optical image via the optical system, converting the optical image to image signals, and outputting the image signals; a correction coefficient output circuit for outputting a correction coefficient for correcting the image signal with respect to a defect pixel of the image sensor, wherein the correction coefficient is determined based on the distortion aberration characteristics and a position of a peripheral pixel around the defect pixel; and a correction value computing circuit for computing a correction value with respect to the image signal of the defect pixel, based on the image signal of the peripheral pixel and the correction coefficient.

Abstract: A shading correction circuit of the present invention includes an image pickup device having photo detectors arranged on its receptive surface, and a shading correction part for performing shading correction on an output signal of the image pickup device. The image pickup device has an effective pixel area and an upper optical black part. The shading correction part has a correction coefficient generating part and a correction processing part. The correction coefficient generating part thereof extracts shading variation according to an output of the upper optical black part, and generates a correction coefficient for the shading variation. The correction processing part thereof performs shading correction on an image signal by using the correction coefficient generated by the correction coefficient generating part.

Abstract: A circuit and method of detecting a saturation level of an image sensor including a photodiode using a black pixel circuit included in the image sensor. The saturation level detecting circuit includes a pixel unit, a reset node and a detection controller. The pixel unit includes a floating diffusion node connected to, or disconnected from, the photodiode and outputs a voltage signal corresponding to the voltage of the floating diffusion node. The reset node is connected to, or disconnected from, the floating diffusion node. The detection controller transfers a power voltage or a reference voltage to the reset node.

Abstract: A dc level control method for holding a dc level of a clamp portion in an electric signal to be a prescribed value is disclosed, wherein the method comprises the steps of: comparing a dc level of a sampling interval in said electric signal with a predetermined reference value to obtain a difference between said dc level and said reference value using an A/D converting section for dc level comparison which has a lower bit resolution than an A/D converting section for digital signal processing of said electric signal; and feeding back a clamp signal to said electric signal so that said obtained difference between said dc level and said reference value substantially becomes zero. This method is suitable for applying to a signal processing system for a solid state imaging apparatus.

Abstract: The present invention provides an image capturing apparatus which enables a desired image quality to be maintained regardless of transfer efficiency of a CCD image capturing element. R, G and B signals (CCD-RAW data) are acquired from the CCD image capturing element. In addition, various information, namely transfer efficiency of the CCD image capturing element, camera sensitivity upon photography, drive frequency of the CCD image capturing element, WB gains of the acquired R, G and B signals, pixel count, internal temperature of camera or temperature of the CCD image capturing element, and CCD color filter array of the CCD image capturing element are acquired. Signal processing on the acquired R, G and B signals is changed according to the acquired information in order to suppress image quality deterioration due to transfer efficiency degradation.

Abstract: A pixel with a photosensor and a transfer transistor having a split transfer gate. A first section of the transfer gate is connectable to a first voltage source while a second section of the transfer gate is connectable to a second voltage source. Thus, during a charge integration period of a photosensor, the two sections of the transfer gate may be oppositely biased to decrease dark current while controlling blooming of electrons within and out of the pixel cell. During charge transfer the two gate sections may be commonly connected to a positive voltage sufficient to transfer charge from the photosensor to a floating diffusion region.

Abstract: A differential amplifier has a first input terminal to which a voltage of a noise signal of the solid-state imaging device is supplied and a second input terminal to which a voltage of a temporary data signal having the noise signal of the solid-state imaging device superposed thereon is supplied. The differential amplifier inverts an output signal when a magnitude relationship in voltage between the first and second input terminals becomes reverse. A measurement circuit measures a variation amount of a voltage of the second input terminal from when the voltage of the second input terminal begins to vary in a direction to reverse the magnitude relationship to when the output signal of the differential amplifier is inverted, and outputs a measurement result as a digital value indicating a voltage of a real data signal obtained by removing the noise signal from the temporary data signal.

Abstract: Apparatus and a method for improving image quality in an image sensor, where a black level of a photographed image is calibrated and luminance of an image signal is expanded within the allowable range of luminance through knee correction for the image signal in which the black level is calibrated. Interpolation for restoring a dead pixel may be achieved before gamma correction for image signal.

Abstract: An auto-focusing method and a digital image processing apparatus using the same are disclosed. The auto-focusing method includes: setting a reference noise level if an illuminance of a photographing area is larger than a predetermined reference value, and setting a variable noise level that varies according to the illuminance of photographing area if the illuminance of photographing area is smaller than or equal to the predetermined reference value; calculating a focus value of each position of the focus lens while driving the focus lens within the predetermined lens-driving range in the unit of a step and selecting a maximum focus value of the predetermined lens-driving range among the calculated focus values, wherein in the calculating of the focus value, the noise level is subtracted from a pixel data that is larger than the noise level and the result of subtracting is used as the pixel data to calculate the focus value.

Abstract: A method for compensating for dark current in an image sensor array. In a representative embodiments, the method includes determining a nominal average dark current for the image sensor array, determining location of each pixel in the image sensor array, obtaining a nominal dark current associated with each pixel based on the nominal average dark current and on the location of the pixel, and subtracting the associated nominal dark current from the image signal for each pixel. At least two of the pixels have differing associated nominal dark currents. In other representative embodiments compensation values for dark currents and for differences in channel processing are determined during the same time period.

Abstract: A noise reduction apparatus of a digital camera which uses an imaging device for imaging a photographic subject, carries out a specified number of dark exposure operations, to obtain the same specified number of dark output values for each picture element of the imaging device, in which the photographic subject is imaged, under the condition where the imaging device is shaded, after a normal exposure operation in which the photographic subject is imaged. The apparatus calculates a representative value for each dark exposure operation, based on the dark output values. The apparatus calculates a ratio based on the representative values. The apparatus calculates noise components caused by the dark current in each picture element of the imaging device in the normal exposure operation on the basis of the ratio. The apparatus reduces the noise components from respective output values of each picture element, produced in the normal exposure operation.

Abstract: According to this invention, even when an image capturing apparatus has a plurality of read modes, the frame rate can be prevented from decreasing in a high-resolution video photographing mode. The image capturing apparatus includes an image sensor and drive unit. The image sensor includes an effective image sensing area having a plurality of pixels at the center portion of the image sensor, and a light-shielded pixel area having a plurality of light-shielded pixels at the peripheral portion of the image sensor. The drive unit can drive the image sensor in a plurality of modes, and drives the image sensor such that the plurality of read modes are almost equal to the light-shielded pixel read time BL?MIN for reading pixel signals in the light-shielded pixel area.

Abstract: An intra-subject device is introduced into a subject to acquire information of the interior of the subject and has a lighting member to output an illuminating light for illuminating the interior of the subject and an imaging member to acquire an image of the interior of the subject. The intra-subject device also has a parameter memory to store a parameter for canceling a noise contained in color information of the image. The intra-subject device also has a radio-transmitting section that radio-transmits the image information, to which the parameter stored in the parameter memory is added.

Abstract: A solid state image pickup device 110 is provided with: a plurality of pixel units 10 that are arranged two-dimensionally and include a photoelectric conversion unit (photodiode PD) that converts light into a charge and an amplification unit (amplifier Q13) that converts the charge into a voltage and outputs it; a plurality of noise signal removal units (noise cancellation units 40) that are provided one for each column and remove noises contained in the voltage outputted from the amplifier Q31 of the pixel unit 10 belonging to the column; and a plurality of column amplification units (column amplifiers 70) that amplify the voltage outputted from the amplifier Q13 of the pixel unit 10 and output the amplified voltage to the noise cancellation unit 40, and enables increase in sensitivity and reduction in noise with low power consumption.

Abstract: An image-capturing apparatus includes an image-capturing device having an effective pixel area formed of a plurality of areas having different dark current characteristics and a light-shielded pixel area arranged in the region surrounding the effective pixel area; a storage unit configured to prestore a correlation between dark current differences among the plurality of areas and dark current of the light-shielded pixel area; a detector configured to detect the dark current of the light-shielded pixel area during image capturing; a dark current difference obtaining unit configured to, on the basis of the correlation stored in the storage unit, obtain dark current differences among the plurality of areas during image capturing from the dark current of the light-shielded pixel area; and a correction processor configured to correct a video signal obtained from the effective pixel area on the basis of the dark current differences during the image capturing.

Abstract: The application describes an X-ray detector, which uses direct X-ray conversion (DiCo) combined with CMOS pixel circuits. DiCo materials have to be used with high voltage to achieve a high field strength. This makes the sensor prone to leakage currents, which falsify the measured charge result. Moreover, most direct conversion materials suffer from large residual signals that lead to temporal artifacts (ghost images) in an X-ray image sequence. A circuit is described, which senses the sensor's dark current including residual signals from previous exposures before the sensor is exposed (again) to X-ray, and freezes relevant circuit parameters at the end of the sensing phase in such way, that the dark current (leakage current and residual signal) can still be drained during exposure. Therefore, the charge pulses generated in the sensor due to X-ray exposure can be integrated without charges carried by the leakage current or residual signal, thus obtaining a more accurate estimate of the deposited X-ray energy.

Abstract: An object of this invention is to enable performing accurate DC recovery operation for an output signal from an image sensing element, and obtaining a high-quality image free from any image degradation such as a horizontal streak. To achieve this object, an image sensing apparatus includes first and second clamping circuits on the output side of an image sensing element. The image sensing element outputs a signal from an effective pixel region, a first reference signal for DC recovery of an image signal that is set for each row, and a second reference signal that is uniformly set for the pixel region. The first clamping circuit DC-recovers a signal from the effective pixel region for each row on the basis of the first reference signal. The second clamping circuit uniformly DC-recovers signals from the effective pixel region for the pixel region on the basis of the second reference signal.

Abstract: A solid-state image device including pixels arranged two-dimensionally, the pixels each including a photoelectric converter for converting incident light into an electric signal, is provided. The solid-state image device includes an output amplifier configured to amplify a photoelectric conversion output from each of the pixels, and a reference voltage amplifier configured to output a reference voltage. The solid-state image device selectively outputs the photoelectric conversion output and the reference voltage.

Abstract: A digital camera captures high quality long exposure images by capturing and summing several images of the same scene. The effective ISO of the camera is reduced by scaling the summed image, thus reducing image noise and improving long exposure quality.

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 complementary metal oxide semiconductor (CMOS) image sensor and a method for operating the same are provided. The CMOS image sensor includes a pixel array unit having a matrix of pixels, wherein each pixel comprises a charge transfer element for transferring charge collected in a photoelectric conversion element to a charge detection element, and a row drive unit for supplying a voltage to the charge transfer element during part of a charge integration period of the photoelectric conversion element, wherein the supplied voltage causes the charge transfer element to have a negative potential.

Abstract: An electronic camera includes a CCD imager. The CCD imager has an imaging surface in which two sensor areas are formed. A raw image produced in one sensor area is output from a channel CH1, and a raw image produced in the other sensor area is output from a channel CH2. The raw image from the channel CH1 is clamped by a clamp circuit at a clamp level LV1, and the raw image from the channel CH2 is clamped by another clamp circuit at a clamp level LV2. The clamp level LV1 matches an optical black level VCL of the raw image from the channel CH1. The clamp level LV2 matches a subtraction level “VCL?(VAL?VAR)” determined by subtracting a difference between a preliminary feeding level VAL of the raw image from the channel CH1 and a preliminary level VAR of the raw image from the channel CH2, from the black level VCL of the raw image from the channel CH1.

Abstract: An imaging device includes an imaging sensor, a switching section, and a controlling section. The imaging sensor includes a light receiving surface to which light receiving elements capable of addressing reading are arranged, and having, on the light receiving surface, an imaging area capturing a subject image and an optical black area outputting a signal of a dark current component, the optical black area which the light receiving elements are covered with a light shielding member. The switching section switching a first state and a second state. The controlling section reads a signal level by each partial area at the optical black area when a dark image is captured in the second state after capturing a normal image in the first state, sequentially compares with the signal level at a corresponding position of the normal image, and controls a exposure time of the dark image according to the comparison result.

Abstract: A digital camera captures high quality long exposure images by capturing and summing several images of the same scene. The effective ISO of the camera is reduced by scaling the summed image, thus reducing image noise and improving long exposure quality.

Abstract: A black level calibration (BLC) system is disclosed. A readout chain receives and amplifies dark signal, and generates corresponding digital output. A level integrator performs integration of calibration levels in multiple steps according to the digital output, thereby achieving wide calibration range.

Abstract: A noise eliminator is provided which can highly compress and store dark current noise components while maintaining characteristics, including many high frequency components. A noise distribution analysis section 10 determines the magnitude distribution of dark current noise components of at least some pixels, and then computes the threshold and typical values for quantization based on this distribution. A quantization section 12 quantizes the dark current noise components based on the computed threshold value, and a memory 14 stores the quantized dark current noise components. An inverse quantization section 16 inversely quantizes the quantized dark current noise components stored in the memory 14 with reference to the typical value computed by the noise distribution analysis section 10. The inversely quantized dark current noise components are supplied to a subtraction section 18, and the subtraction section 18 subtracts the inversely quantized dark current noise components from an image signal.

Abstract: In a camera having a gamma-correction circuit on an output signal processing path of a CCD, an incident light path leading to the CCD is kept opening in a state where nonlinear gamma-correction processing in the gamma-correction processing circuit is prohibited, first image data (CCD output data; DATA1) are generated based on electric signal output from the CCD, incident light path leading to the CCD is kept closing, second image data (CCD output data; DATA2) are generated based on electric signal output from the CCD and lastly, the second image data DATA2 are subtracted from the first image data DATA1, thereby correcting to eliminate dark voltage component included in the first image data DATA1.

Abstract: Smear detect circuitry within an analog front end (AFE) of a digital camera determines when black area pixel values received from an image sensor are indicative of smear leakage. Smear leakage can cause a light vertical line in the resulting digital image. When a sensor that is coupled to a storage element is exposed to a bright light source, storage element overload can cause a leakage charge to leak from the storage element to other storage elements along a transfer line. Smear detect circuitry identifies the transfer line exhibiting smear leakage and excludes pixel values from storage elements along that transfer line from the calculation of a black level value used to calibrate color pixel values. The digital camera displays a smear icon indicating smear leakage in a digital image that is to be taken. A digital file of the digital image includes a header with a smear detect field.

Abstract: In an image sensing apparatus which has an image sensing element having a plurality of pixels which generate charges in correspondence with the amount of incoming light, and a transfer unit which transfers charge signals generated by the plurality of pixels, first reading of said transfer unit and a second reading are performed after the image sensing element is exposed for a predetermined period of time and before the charge signals accumulated on the pixels are transferred to the transfer unit, wherein a transfer speed used in the second reading is different from a transfer speed used in the first reading.

Abstract: An image sensor includes one or more photodetectors for collecting charge in response to incident light and a storage region adjacent each photodetector. A transfer mechanism transfers charge from each photodetector to a respective storage region. A conductive layer or a polysilicon layer is situated over each storage region. A bias voltage terminal is connected to each conductive layer or polysilicon layer for receiving a bias voltage to bias the conductive layer or polysilicon layer to a predetermined voltage level.

Abstract: The specification and drawings present a new method, apparatus and software product for storing camera module characteristics of a camera module (or camera) of an electronic device provided during production (e.g., a factory testing) of the electronic device in a non-volatile memory of the camera module, such that the camera module characteristics are used by the electronic device for taking and processing images and/or identifying the camera module. The electronic device can be a wireless communication device, a portable electronic device, a camera, a camera-phone mobile device, etc.

Abstract: An imaging sensor pixel array includes a semiconductor substrate, a plurality of active pixels and at least one black reference pixel. The plurality of active pixels are disposed in the semiconductor substrate for capturing an image. Each of the active pixels includes a first region for receiving light including a p-n junction for accumulating an image charge and active pixel circuitry coupled to the first region to readout the image charge. The black reference pixel is also disposed within the semiconductor substrate for generating a black level reference value. The black reference pixel includes a second region for receiving light without a p-n junction and black pixel circuitry coupled to the photodiode region without the p-n junction to readout a black level reference signal.

Abstract: A CMOS image sensor includes a plurality of pixels arranged column and rows in an array; a column circuit for storing reset values and a value after integration; a correlated double sampler which derives an image signal from the reset and the value after integration; and an anti-eclipse circuit physically separately from the column circuit and electrically connected to one or shared between multiple columns of pixels for restoring corrupted column voltage on a column of pixels.

Abstract: In a case when a structure of forming a p+ layer on a substrate rear surface side is employed in order to prevent dark current generation from the silicon boundary surface, various problems occur. According to this invention, an insulation film 39 is provided on a rear surface on a silicon substrate 31 and a transparent electrode 40 is further provided thereon, and by applying a negative voltage with respect to the potential of the silicon substrate 31 from a voltage supply source 41 to the insulation film 39 through the transparent electrode 40, positive holes are accumulated on a silicon boundary surface of the substrate rear surface side and a structure equivalent to a state in which a positive hole accumulation layer exists on aforesaid silicon boundary surface is to be created. Thus, various problems in the related art can be avoided.

Abstract: An image sensing apparatus has an image sensing element for photoelectric conversion, a shutter for selectively creating a light-shielded state and non-light-shielded state for the image sensing element, a bright signal storage unit for storing a bright signal output from the image sensing element in the non-light-shielded state, a dark signal storage unit for storing a dark signal output from the image sensing element in the light-shielded state, an operation unit for subtracting the dark signal from the bright signal to obtain a signal with suppressed dark noise, and a control unit for controlling read of bright and dark signals from the image sensing element in accordance with the relationship between the exposure time of the image sensing element and the photographing time interval.

Abstract: Methods and apparatuses for row-wise dark level non-uniformity compensation of imaging sensor pixel signals. A column dependent dark reference value is determined as one of a linear and parabolic function of signal values from two areas of dark reference pixels and a column location and then used for dark level non-uniformity compensation of signal values from imaging pixels.

Abstract: An image pickup apparatus includes an imaging device configured to convert an optical image of an object into an electrical signal, an optical black level extraction unit configured to extract an optical black level included in an image signal obtained by photoelectric conversion by the imaging device, a blanking level extraction unit configured to extract a blanking level in a blanking period of the image signal, an abnormality detection unit configured to detect an abnormality of the optical black level, and a clamp unit configured, at a normal time when the abnormality is not detected by the abnormality detection unit, to clamp the optical black level to a first target value with the optical black level extracted by the optical black level extraction unit as a reference, and at an abnormal time when the abnormality is detected by the abnormality detection unit, to clamp the optical black level to a second target value with the blanking level extracted by the blanking level extraction unit as a reference.