JP2008118384A - Imaging apparatus and driving method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To stably generate image data even when affected by the delay or the like of an output signal of an imaging device due to an environmental change such as a temperature change. <P>SOLUTION: An image pick-up signal from pixels in a portion of an area in an imaging surface of an imaging device 14 is sampled at a plurality of sampling timing, and an image processing circuit part 20 creates shading data in each sampling timing on the basis of respective image picked-up signals obtained from the imaging device 14 in accordance with the plurality of sampling timing. A system control part 50 performs control so as to extract shading data whose difference from standard shading data is the smallest among a plurality of pieces of shading data created by the image processing circuit part 20 and to sample image picked-up signals from pixels in an area other than the portion of area at sampling timing in the extracted shading data. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an imaging apparatus including an imaging element and a driving method thereof, and more particularly to an imaging apparatus that performs sampling setting of an output signal in the imaging element and a driving method thereof.

  Conventionally, solid-state imaging devices such as CCDs and CMOS area sensors are generally used in imaging devices such as digital cameras and video cameras.

In recent years, the number of pixels of a solid-state imaging device has been increased due to the improvement of technology, and it is desired to increase the speed of reading output signals from the solid-state imaging device in association with an increase in the number of pixels.
It is possible to increase the readout speed by driving the image sensor at high speed, but at that time, the output signal phase fluctuations due to environmental changes such as temperature changes and changes over time Is a problem.

  Therefore, when the output signal is sampled by the sample and hold circuit, the output signal is sampled when the light source is turned on at each sampling timing in which a plurality of phases are set in advance prior to the actual operation such as when the power is turned on. And a technique is proposed in which a reliable output signal is obtained during the stable period by selecting a sampling timing at which the output level is the maximum value and the stable period is equal to or greater than a predetermined period (for example, Patent Document 1). See).

  In addition, some of the image sensors have characteristics such as non-uniform voltage due to resistance components of the power supply line in the image sensor, element variations, fixed pattern noise generated due to differences in wiring resistance in the readout path, etc., so-called circuit noise. Some have dark shading. Therefore, a horizontal dark shading correction method using one-dimensional correction data obtained by projecting a dark photographed image in the manufacturing process or the like has been proposed (for example, see Patent Document 2).

Japanese Patent Laid-Open No. 2005-217459 JP 2003-333434 A

  However, when an image sensor with dark shading is read out at high speed, the output waveform has a large level difference depending on the region, depending on the top, bottom, left, right, etc. There is a difference and dark shading increases. In addition, since the stabilization period is short, if the output is accelerated or a delay occurs due to temperature or the like, the sampling timing shift becomes a large level difference as it is.

  For such an image sensor, when the technique described in Patent Document 1 is applied, dark shading is not taken into consideration, so depending on the characteristics of phase fluctuations such as dark shading and output delay, the appropriate timing may not be achieved. there were. This causes a problem that it is difficult to stably generate image data. Further, since the image data is obtained from the difference in level between the preset black reference data and the light output, it is necessary to prepare preset black reference data. In particular, in order to accurately obtain an image sensor having dark shading, it is necessary to shoot a black image under the same conditions as the light image.

  In addition, in order to determine the sampling timing prior to the actual photographing, it is necessary to acquire photographing data under a light source, which is not practical in an imaging apparatus having no light source such as a digital camera. In addition, since it is necessary to acquire data prior to the actual photographing, there is a possibility that a photo opportunity will be missed due to a release time lag after the power is turned on.

  In the technique described in Patent Document 2, since dark shading is merely corrected, when phase shift occurs due to environmental changes such as temperature changes, sampling is not performed at an appropriate position, and output is performed. This may cause a decrease in level. That is, in this case, it is difficult to stably generate image data.

  The present invention has been made in view of the above-described problems, and realizes stable generation of image data even when there is an influence such as delay of an output signal of an image sensor due to an environmental change such as a temperature change. An object of the present invention is to provide an imaging apparatus and a driving method thereof.

  An image pickup apparatus according to the present invention includes an image pickup device having pixels arranged in a two-dimensional matrix on an image pickup surface, and a plurality of image pickup signals from pixels in a partial region of the image pickup surface of the image pickup device. Sampling means for performing sampling according to the sampling timing, and shading data by calculating shading for each sampling timing based on the imaging signals obtained from the imaging elements in accordance with the plurality of sampling timings by the sampling means, respectively. A difference between the creation means to create, a storage means for storing standard shading data at a standard sampling timing as a standard, and the standard shading data among the plurality of shading data for each sampling timing created by the creation means Shade with minimum And extraction means for extracting image data, and control for causing the sampling means to sample image signals from pixels other than the partial area on the imaging surface at a sampling timing in the shading data extracted by the extraction means And control means for performing

  According to another aspect of the present invention, there is provided a driving method for an image pickup apparatus including an image pickup device having pixels arranged in a two-dimensional matrix on an image pickup surface, and image pickup signals from pixels in a part of the image pickup surface of the image pickup device. An imaging apparatus driving method comprising: sampling means for sampling at a plurality of sampling timings; and storage means for storing standard shading data at a standard sampling timing as a standard. Accordingly, based on the imaging signal obtained from the imaging element, a step of calculating shading for each sampling timing to create shading data, and a plurality of shading data for each of the created sampling timings Standard shading The step of extracting shading data that minimizes the difference from the data, and the sampling means at a sampling timing in the extracted shading data of an imaging signal from a pixel in a region other than the partial region on the imaging surface And performing a control of sampling.

  According to the present invention, image data can be stably generated even when there is an influence such as a delay of an output signal of an image sensor due to an environmental change such as a temperature change.

  The best mode for carrying out the present invention will be described below in detail with reference to the accompanying drawings.

FIG. 1 is a block diagram showing a schematic configuration of an imaging apparatus according to an embodiment of the present invention.
The imaging apparatus shown in FIG. 1 has an image processing function (image processing circuit unit 20). In this embodiment, an example in which a digital camera is applied as an imaging device will be described. Other imaging devices include, for example, digital video cameras, camera-equipped mobile terminals (including camera-equipped mobile phones), and the like that can convert an optical image of a subject and output an electrical image signal. If so, the present invention can be applied.

  As shown in FIG. 1, the imaging apparatus according to the present embodiment includes a camera body 100, recording media 200 and 210 configured to be detachable from the camera body 100, and an exchange configured to be detachable from the camera body 100. A lens type lens unit 300 is included.

First, the configuration of the lens unit 300 will be described.
An imaging lens 310 includes a plurality of lenses. Reference numeral 312 denotes a stop for adjusting the amount of light (optical image) incident from the imaging lens 310. Reference numeral 306 denotes a lens mount that mechanically couples the lens unit 300 to the camera body 100. The lens mount 306 includes various functions for electrically connecting the lens unit 300 to the camera body 100.

  Reference numeral 322 denotes a connector that electrically connects the lens unit 300 to the camera body 100. The connector 322 transmits a control signal, a status signal, a data signal, and the like between the camera body 100 and the lens unit 300, and also has a function of receiving various power supplies or supplying various power supplies. Further, the connector 322 may be configured to transmit not only electrical communication but also optical communication, voice communication, and the like. Reference numeral 320 denotes an interface for connecting the lens unit 300 to the camera body 100 via the connector 322.

  Reference numeral 340 denotes an aperture control unit that controls the aperture 312 in cooperation with a shutter control unit 40 that controls the shutter 12 of the camera body 100 described later, based on photometry information from the photometry control unit 46 of the camera body 100.

  Reference numeral 342 denotes a focus control unit that controls focusing of the imaging lens 310. A zoom control unit 344 controls zooming of the imaging lens 310.

  A lens system control unit 350 performs overall control of the entire lens unit 300. The lens system control unit 350 includes a memory for storing operation constants, variables, programs, and the like. Furthermore, the lens system control unit 350 holds identification information such as a number unique to the lens unit 300, management information, function information such as an open aperture value, a minimum aperture value, and a focal length, and current and past setting values. Non-volatile memory is also provided.

Next, the configuration of the camera body 100 will be described.
A lens mount 106 mechanically couples the camera body 100 and the lens unit 300. Reference numerals 130 and 132 denote mirrors that guide the light beam (optical image) incident on the imaging lens 310 to the optical viewfinder 104 by a single-lens reflex system. The mirror 130 may be configured as a so-called quick return mirror or a half mirror. Reference numeral 12 denotes a shutter for giving a necessary exposure amount to an image sensor 14 described later.

  Reference numeral 14 denotes a (solid-state) imaging device that converts an optical image of a subject incident from the imaging lens 310 into an electrical signal (imaging signal). The imaging device 14 of the present embodiment includes pixels arranged in a two-dimensional matrix on the imaging surface shown in FIG. As shown in FIG. 2, on the imaging surface of the imaging device 14, a light-shielding light-shielding unit composed of a light-receiving unit 141 that receives incident light rays (optical image) and pixels of several tens of columns and several tens of rows. A CMOS area sensor having a portion (OB portion) 142 is formed. That is, on the imaging surface of the imaging element 14, a light shielding part (OB part) 142 is formed in a part of the area, and a light receiving part 141 is formed in an area other than the part of the area. The light shielding unit (OB unit) 142 is formed at least in a region including pixels in one horizontal row formed on the imaging surface of the imaging device 14, and the light receiving unit 141 includes pixels in a Bayer array. Are arranged in a two-dimensional matrix. An imaging signal that is an electrical signal imaged by each pixel on the imaging surface of the imaging element 14 is read to the A / D converter 16 for each row of pixels.

  Further, the imaging element 14 has characteristics such as horizontal dark shading as shown in FIG. 3 and output delay due to temperature change. Here, the solid line shown in FIG. 3 indicates horizontal dark shading at normal temperature, and the dashed line in FIG. 3 indicates horizontal dark shading when the temperature is high.

  In the present invention, the sampling timing for reading the image signal of the light receiving unit 141 to the A / D converter 16 is determined using shading data based on the image signal from the light shielding unit (OB unit) 142. Details thereof will be described later. The light beam incident on the imaging lens 310 is guided by the single-lens reflex system through the aperture 312 as the light amount limiting unit, the lens mounts 306 and 106, the mirror 130, and the shutter 12, and forms an optical image on the imaging element 14.

  Reference numeral 16 in FIG. 1 denotes an A / D converter that converts an analog signal output from the image sensor 14 into a digital signal (image data). A timing generation circuit unit (sampling means) 18 supplies a clock signal and a control signal to the image sensor 14, the A / D converter 16, and the D / A converter 26, respectively, and includes a memory control circuit unit 22 and a system control unit. 50.

FIG. 4 is a timing chart showing each control signal from the timing generation circuit unit 18 and an analog signal output from the image sensor 14.
In FIG. 4, from the top, a drive clock signal for outputting an electric signal photoelectrically converted by the image sensor 14, an analog signal output from the image sensor 14, and the analog signal are converted into an A / D converter 18. Shows the ADCLK signal for sampling. In this embodiment, an analog signal is sampled at the rising edge of the ADCLK signal, and the timing of the ADCLK signal can be delayed by a predetermined interval time (tap) by a built-in DLL function. Is possible.

Further, as shown in FIG. 4, the analog signal read from the image sensor 14 has output differences as S1, S2, S3,... For each pixel output, and this difference appears as dark shading.
Also, the dashed line in the analog signal in FIG. 4 indicates the analog signal delayed by the influence of temperature change or the like.

  An image processing circuit unit 20 performs predetermined pixel interpolation processing and color conversion processing on the image data from the A / D converter 16 or the image data from the memory control circuit unit 22. The image processing circuit unit 20 performs predetermined arithmetic processing using the image data output from the A / D converter 16. Then, based on the obtained calculation result, the system control unit 50 controls the shutter control unit 40 and the distance measurement control unit 42 in a TTL (through the lens) type autofocus (AF) process, automatic Exposure (AE) processing and flash pre-emission (EF) processing are performed.

  Further, the image processing circuit unit 20 performs predetermined arithmetic processing using the image data output from the A / D converter 16, and performs TTL auto white balance (AWB) processing based on the obtained arithmetic result. Is going. The image processing circuit unit 20 also functions as a creation unit that performs shading calculation processing based on the imaging signal output from the light shielding unit (OB unit) 142 of the imaging device 14 and creates shading data.

  In the example shown in FIG. 1 in the present embodiment, since the distance measurement control unit 42 and the photometry control unit 46 are provided exclusively, the system control unit 50 uses the distance measurement control unit 42 and the photometry control unit 46. Then, each of AF processing, AE processing, and EF processing may be performed. In this case, the AF processing, AE processing, and EF processing using the image processing circuit unit 20 may not be performed. Further, AF processing, AE processing, and EF processing are performed using the distance measurement control unit 42 and the photometry control unit 46, and further, AF processing, AE processing, and EF processing are performed using the image processing circuit unit 20. It is good also as composition which performs.

  A memory control circuit unit 22 includes an A / D converter 16, a timing generation circuit unit 18, an image processing circuit unit 20, an image display memory 24, a D / A converter 26, a memory 30, and a compression / decompression circuit unit 32. To control. The image data output from the A / D converter 16 is written into the image display memory 24 or the memory 30 through the image processing circuit unit 20 and the memory control circuit unit 22 or only through the memory control circuit unit 22. .

  Reference numeral 24 denotes an image display memory. Reference numeral 26 denotes a D / A converter. Reference numeral 28 denotes an image display unit composed of a TFT LCD or the like, and display image data written in the image display memory 24 is displayed by the image display unit 28 via the D / A converter 26.

  An electronic viewfinder (EVF) function can be realized by sequentially displaying captured image data using the image display unit 28. Further, the image display unit 28 can arbitrarily turn on / off the display according to an instruction from the system control unit 50, and when the display is turned off, the power consumption of the camera body 100 can be greatly reduced. Can do.

  Reference numeral 30 denotes a memory for storing captured still image data and moving image data, which has a sufficient storage capacity to store a predetermined number of still image data and a predetermined time of moving image data. Yes. Thus, even in continuous shooting or panoramic shooting in which a plurality of still images are continuously shot, a large amount of image data can be written to the memory 30 at high speed. The memory 30 can also be used as a work area for the system control unit 50.

  A compression / decompression circuit unit 32 compresses / decompresses image data using a known compression method such as adaptive discrete cosine transform (ADCT). The compression / decompression circuit unit 32 reads the image data stored in the memory 30, performs compression processing or decompression processing, and writes the processed image data in the memory 30 again.

  A shutter control unit 40 controls the shutter 12 in cooperation with an aperture control unit 340 that controls the aperture 312 based on photometric information from the photometry control unit 46. Reference numeral 42 denotes a distance measurement control unit for performing AF (autofocus) processing. The distance measurement control unit 42 causes the light incident on the imaging lens 310 to enter the single lens reflex system through the aperture 312, the lens mounts 306 and 106, the mirror 130, and the distance measurement sub-mirror (not shown). The in-focus state of the image formed as an optical image is measured.

  A photometric control unit 46 performs AE (automatic exposure) processing. The light metering control unit 46 allows the light metering control unit 46 to enter the optical image by causing the light beam incident on the photographing optical system 310 to be incident on the single lens reflex system via the aperture 312, the lens mounts 306 and 106, the mirror 130, and the photometric sub mirror (not shown). As a result, the exposure state of the image formed is measured.

  A flash unit 48 has an AF auxiliary light projecting function and a flash light control function. The photometry control unit 46 also has an EF (flash dimming) processing function in cooperation with the flash unit 48. In addition, the photometry control unit 46 in the present embodiment performs photometry using a well-known divided photometry method including a plurality of photometry areas, and measures a plurality of points (for example, 35 points) in a shooting scene, and exposure is performed according to the result. Shall be determined.

  As described above, the exposure control and the AF control may be performed based on the calculation result calculated by the image processing circuit unit 20 using the image data from the A / D converter 16. In this case, the system control unit 50 can perform exposure control and AF control using the video TTL system for the shutter control unit 40, the aperture control unit 340, and the distance measurement control unit 42. The AF control may be performed using the measurement result obtained by the distance measurement control unit 42 and the calculation result obtained by calculating the image data from the A / D converter 16 by the image processing circuit unit 20. Furthermore, exposure control may be performed using the measurement result obtained by the photometry control unit 46 and the calculation result obtained by calculating the image data from the A / D converter 16 by the image processing circuit unit 20.

  Reference numeral 50 denotes a system control unit that controls the entire camera body 100, and includes a known CPU. Further, the system control unit 50 determines a plurality of shading data created by the image processing circuit unit 20 to minimize the difference from the standard shading data stored in the nonvolatile memory 56, Applicable shading data is extracted. The system control unit 50 sets the timing by the timing generation circuit unit 18 via the memory control circuit unit 22 based on the extracted shading data.

  Reference numeral 52 denotes a memory that stores constants, variables, programs, and the like for operation of the system control unit 50. Reference numeral 54 denotes a notification unit for notifying the outside of an operation state, a message, and the like using characters, images, sounds, and the like in accordance with execution of a program in the system control unit 50. As the notification unit 54, for example, a display unit that performs visual display using an LCD, an LED, or the like, or a sound generation element that performs notification by voice is used. The notification unit 54 is configured by a combination of one or more of these. In particular, in the case of a display unit, it is installed at a single or a plurality of locations near the operation unit 70 of the camera body 100 that are easy to see. The notification unit 54 has a part of its function installed in the optical viewfinder 104, a lamp (not shown), or the like.

  Among the display contents of the notification unit 54, the following are displayed on the LCD or the like. First, there are displays related to the shooting mode such as single shot / continuous shooting display, self-timer display, and the like. In addition, there are displays relating to recording such as compression rate display, recording pixel number display, recording number display, and remaining image number display. In addition, there are displays relating to shooting conditions such as shutter speed display, aperture value display, exposure correction display, flash display, and red-eye reduction display. In addition, there are a macro shooting display, a buzzer setting display, a clock battery remaining amount display, a battery remaining amount display, an error display, an information display by a multi-digit number, and an attachment / detachment state display of the recording media 200 and 210. Further, the attachment / detachment state display of the lens unit 300, the communication I / F operation display, the date / time display, the display indicating the connection state with the external computer, the display of the dark correction processing setting, and the like are also performed.

  In addition, among the display contents of the notification unit 54, examples of what is displayed in the optical finder 104 include the following. In-focus display, photographing preparation completion display, camera shake warning display, flash charge display, flash charge completion display, shutter speed display, aperture value display, exposure correction display, recording medium writing operation display, and the like.

  Further, among the display contents of the notification unit 54, examples of what is displayed by an LED or the like include the following. In-focus display, shooting preparation completion display, camera shake warning display, flash charge display, flash charge completion display, recording medium writing operation display, macro shooting setting notification display, secondary battery charge display, and the like.

  Further, among the display contents of the notification unit 54, what is displayed on the lamp or the like includes, for example, a self-timer notification lamp. This self-timer notification lamp may be shared with the AF auxiliary light.

  Reference numeral 56 denotes an electrically erasable / recordable nonvolatile memory in which a program and the like to be described later are stored. For example, an EEPROM or the like is used. The nonvolatile memory 56 stores setting values such as various parameters, correction data, and the like in addition to the above programs. The non-volatile memory 56 stores standard (dark) shading data at a standard sampling timing that is a standard for reading an imaging signal from the imaging device 14 and also has a function of a storage unit in the present invention. In the present embodiment, the standard (dark) acquired at the standard sampling timing determined as a desired S / N or higher after incorporating the image sensor 14 having the CMOS area sensor at the imaging device manufacturing factory. Shading data is stored in the non-volatile memory 56.

  Reference numerals 60, 62, 64, 66, and 70 are operation means for inputting various operation instructions of the system control unit 50, and include one or a plurality of switches, dials, touch panels, pointing by line-of-sight detection, voice recognition devices, and the like. Composed of a combination. Here, a specific description of these operating means will be given below.

  Reference numeral 60 denotes a mode dial switch, which switches and sets each function shooting mode such as an automatic shooting mode, a program shooting mode, a shutter speed priority shooting mode, an aperture priority shooting mode, a manual shooting mode, and a focus depth priority (depth) shooting mode. be able to. In addition, each function shooting mode such as portrait shooting mode, landscape shooting mode, close-up shooting mode, sports shooting mode, night view shooting mode, panoramic shooting mode, and the like can be switched and set.

  Reference numeral 62 denotes a first shutter switch (SW1), which is turned ON while a shutter button (not shown) is being operated (for example, half-pressed), and instructs to start operations such as AF processing, AE processing, AWB processing, and EF processing.

  Reference numeral 64 denotes a second shutter switch (SW2), which is turned on when an operation of a shutter button (not shown) is completed (for example, fully pressed), and instructs operation start of a series of processing including exposure processing, development processing, and recording processing. To do. First, in the exposure process, image data obtained by processing a signal read from the image sensor 14 via the A / D converter 16 and the memory control circuit unit 22 is written in the memory 30, and further, the image processing circuit unit 20 and the memory control circuit are written. Development processing using the calculation in the unit 22 is performed. Further, in the recording process, image data is read from the memory 30, compressed by the compression / decompression circuit unit 32, and written to the recording medium 200 or 210.

  Reference numeral 66 denotes a playback switch, which reads out image data shot in the shooting mode state from the memory 30 or the recording media 200 and 210 and instructs the start of a playback operation to be displayed on the image display unit 28. Further, the playback switch 66 may be used to set each function mode such as a playback mode, a multi-screen playback / erase mode, and a PC connection mode.

  An operation unit 70 includes various buttons and a touch panel. As an example, the operation unit 70 includes a menu button, a set button, a macro button, a multi-screen playback page break button, a flash setting button, a single shooting / continuous shooting / self-timer switching button, a menu movement + (plus) button, a menu movement− Includes a (minus) button. Further, the operation unit 70 includes a reproduction image movement + (plus) button, a reproduction image movement− (minus) button, a photographing image quality selection button, an exposure correction button, a date / time setting button, and the like. The functions of the plus button and the minus button can be selected more easily with numerical values and functions by providing a rotary dial switch. The operation unit 70 also includes an ISO sensitivity setting button that can set the ISO sensitivity by changing the gain setting in the image sensor 14 or the image processing circuit unit 20.

  In addition, the operation unit 70 includes a selection / switch button for setting selection and switching of various functions when performing shooting and playback in panorama mode, and various functions when performing shooting and playback in panorama mode. There is a decision / execution button to set decision and execution. Further, the operation unit 70 has an image display ON / OFF switch for setting ON / OFF of the image display unit 28, and a quick review ON / OFF switch for setting a quick review function for automatically reproducing image data taken immediately after shooting. is there. Further, the operation unit 70 includes a compression mode switch that is a switch for selecting a compression rate for JPEG compression or for selecting a CCD RAW mode in which a signal from an image sensor is directly digitized and recorded on a recording medium.

  The operation unit 70 includes an AF mode setting switch that can set a one-shot AF mode and a servo AF mode. In the one-shot AF mode, an autofocus operation is started when the first shutter switch (SW1) 62 is pressed, and once focused, the focused state is maintained. In the servo AF mode, the autofocus operation is continued while the first shutter switch (SW1) 62 is being pressed.

  Reference numeral 72 denotes a power switch, which can switch between power-on and power-off modes of the camera body 100. In addition, the power switch 72 can be set to switch the power on and power off settings of various accessory devices such as the lens unit 300, the external strobe, and the recording media 200 and 210 connected to the camera body 100.

  Reference numeral 80 denotes a power control unit, which includes a battery detection circuit, a DC-DC converter, a switch circuit that switches blocks to be energized, and the like. The power control unit 80 detects whether or not the power source 86 such as a battery is attached, the type of the power source 86, and the remaining power level, and controls the internal DC-DC converter based on the detection result and the instruction of the system control unit 50. Then, a necessary voltage is supplied to each part including the recording medium for a necessary period.

  Reference numerals 82 and 84 denote connectors for connecting the power control unit 80 and the power source 86. A power source 86 includes a primary battery such as an alkaline battery or a lithium battery, a secondary battery such as a NiCd battery, a NiMH battery, a Li-ion battery, or a Li polymer battery, an AC adapter, or the like.

  Reference numerals 90 and 94 denote interfaces with recording media 200 and 210 such as a memory card and a hard disk, respectively. Reference numerals 92 and 96 denote connectors for connecting to recording media 200 and 210 such as a memory card and a hard disk, respectively. A recording medium attachment / detachment detection unit 98 detects whether or not the recording medium 200 or 210 is attached to the connectors 92 and / or 96.

  In the present embodiment shown in FIG. 1, the description has been made assuming that there are two interfaces and connectors for attaching the recording medium. However, the number of interfaces and connectors for attaching the recording medium may be one or more. It does not matter as a configuration. Moreover, it is good also as a structure provided with combining the interface and connector of a different standard.

  As the interface and the connector, it is possible to configure using interfaces that comply with various storage medium standards. For example, a PCMCIA (Personal Computer Memory Card International Association) card, a CF (Compact Flash (registered trademark)) card, an SD card, or the like. When the interfaces 90 and 94 and the connectors 92 and 96 are configured using a standard conforming to a PCMCIA card, a CF (registered trademark) card, or the like, various communication cards can be connected. Communication cards include LAN cards, modem cards, USB (Universal Serial Bus) cards, and IEEE (Institute of Electrical and Electronic Engineers) 1394 cards. In addition, there are P1284 card, SCSI (Small Computer System Interface) card, PHS, and the like. By connecting these various communication cards, image data and management information attached to the image data can be transferred to and from other computers and peripheral devices such as a printer.

  Reference numeral 104 denotes an optical viewfinder, which guides a light beam incident on the imaging lens 310 through an aperture 312, lens mounts 306 and 106, and mirrors 130 and 132, and forms an optical image for display by a single-lens reflex system. Is possible. Accordingly, it is possible to perform shooting using only the optical viewfinder 104 without using the electronic viewfinder function of the image display unit 28. Further, in the optical viewfinder 104, some functions of the notification unit 54, for example, in-focus state, camera shake warning, flash charging, shutter speed, aperture value, exposure correction, and the like are displayed.

  A communication unit 110 has various communication functions such as RS232C, USB, IEEE1394, P1284, SCSI, modem, LAN, and wireless communication. Reference numeral 112 denotes a connector for connecting the camera body 100 to another device by the communication unit 110, or an antenna in the case of wireless communication.

  Reference numeral 120 denotes an interface for connecting the camera body 100 to the lens unit 300 via the connector 122. Reference numeral 122 denotes a connector for electrically connecting the camera body 100 to the lens unit 300. Here, whether or not the lens unit 300 is attached to the lens mount 106 and / or the connector 122 is detected by a lens attachment / detachment detection unit (not shown). The connector 122 communicates control signals, status signals, data signals, and the like between the camera body 100 and the lens unit 300, and also has a function of supplying various power sources. Further, the connector 122 may be configured to transmit not only electrical communication but also optical communication, voice communication, and the like.

  Reference numerals 200 and 210 denote recording media such as a memory card and a hard disk. The recording media 200 and 210 include recording units 202 and 212 configured by a semiconductor memory, a magnetic disk, and the like, interfaces 204 and 214 with the camera body 100, and connectors 206 and 216 for connecting with the camera body 100, respectively. I have.

  As the recording media 200 and 210, a PCMCIA card, a memory card such as a compact flash (registered trademark), a hard disk, or the like can be used. Of course, it may be constituted by a micro DAT, a magneto-optical disk, an optical disk such as CD-R or CD-WR, a phase change optical disk such as DVD, or the like.

  In addition, although the case of the interchangeable lens single-lens reflex digital camera has been described as the imaging apparatus according to the present embodiment, it is a so-called digital compact camera in which a lens and a lens barrel are integrated with the camera body. Also good.

  Next, with reference to FIG. 5 to FIG. 8, a method for driving the imaging apparatus having the above-described configuration according to the embodiment of the present invention will be described.

  5 and 6 are flowcharts illustrating a method for driving the imaging apparatus according to the present embodiment. This processing program is stored in, for example, a storage medium such as the non-volatile memory 56, loaded into the memory 52, and executed by the CPU in the system control unit 50.

  In FIG. 5, first, the system control unit 50 initializes flags, control variables, and the like by turning on the power source 86 such as battery replacement, and performs necessary initial settings for each unit of the camera body 100 (step S101). ).

  Subsequently, the system control unit 50 detects the setting position of the power switch 72 and determines whether or not the power switch 72 is set to power OFF (step S102). If the result of this determination is that the power switch 72 is set to power OFF, the system control unit 50 changes the display on each display unit to the end state, and the necessary parameters and settings including flags, control variables, etc. The value and setting mode are recorded in the nonvolatile memory 56. Further, the system control unit 50 performs predetermined end processing such as shutting off unnecessary power of each part of the camera body 100 including the image display unit 28 by the power control unit 80 (step S103), and then returns to step S102.

  When it is determined in step S102 that the power switch 72 is set to ON, the system control unit 50 determines that the remaining capacity and operation status of the power source 86 configured by a battery or the like by the power control unit 80 is the operation of the camera body 100. It is determined whether or not there is a problem (step S104). If there is a problem with the power source 86 as a result of this determination (step S104 / NO), the system control unit 50 issues a predetermined warning by image or sound using the notification unit 54 (step S105), and then the step Return to S102.

  On the other hand, if there is no problem with the power supply 86 (step S104 / YES), the system control unit 50 detects the setting position of the mode dial switch 60 and determines whether or not the mode dial switch 60 is set to the shooting mode. Judgment is made (step S106). If the result of this determination is that the mode dial switch 60 is set to a mode other than the shooting mode, the system control unit 50 executes a process according to the selected mode (step S107). After ending, the process returns to step S102.

  On the other hand, if it is determined in step S106 that the mode dial switch 60 is set to the shooting mode, the process proceeds to step S108.

  In step S108, the system control unit 50 first determines whether the recording medium 200 or 210 is loaded. If the result of this determination is that the recording medium 200 or 210 is loaded, the management information of the image data recorded on the recording medium 200 or 210 is acquired. Next, the system control unit 50 further determines whether or not the operation state of the recording medium 200 or 210 has a problem in the operation of the camera body 100, particularly the recording / reproducing operation of the image data with respect to the recording medium 200 or 210.

  If it is determined in step S108 that there is a problem with the operation of the recording medium (step S108 / NO), a predetermined warning is given by an image or sound using the notification unit 54 (step S105), and then step S102 is performed. Return to. On the other hand, if it is determined in step S108 that there is no problem in the operation of the recording medium (step S108 / YES), the process proceeds to step S109.

  In step S <b> 109, the system control unit 50 notifies the various setting states of the camera body 100 using images and sounds using the notification unit 54. Here, when the image display switch of the image display unit 28 is ON, various setting states of the camera body 100 may be displayed on the image display unit 28.

  Subsequently, in step S110 of FIG. 6, the system control unit 50 determines whether or not the first shutter switch (SW1) 62 is pressed and turned on. If the result of this determination is that the first shutter switch (SW1) 62 has not been pressed and turned on, the process returns to step S102. On the other hand, if the first shutter switch (SW1) 62 is pressed and turned on, the process proceeds to step S111.

  In step S <b> 111, the system control unit 50 performs a distance measurement process to focus the imaging lens 310 on the subject, and performs a light measurement process to perform a distance measurement / photometry process for determining an aperture value and a shutter speed. The system control unit 50 determines the charge accumulation time of the image sensor 14 according to the shutter speed determined here. Further, the system control unit 50 sets the flash flag and sets the flash unit 48 if necessary as a result of the photometric processing.

  When the distance measurement / photometry processing is completed, the process proceeds to step S112, where the system control unit 50 determines whether the second shutter switch (SW2) 64 is pressed and turned on. If the result of this determination is that the second shutter switch (SW2) 64 is not pressed and turned on, the process proceeds to step S113. In step S113, the system control unit 50 determines whether or not the first shutter switch (SW1) 62 is in an ON state. If the first shutter switch (SW1) 62 is in an ON state, the system control unit 50 returns to step S112 and is in an ON state. When is released and turned OFF, the process returns to step S102.

  If it is determined in step S112 that the second shutter switch (SW2) 64 is pressed and turned on (step S112 / YES), the process proceeds to step S114. In step S <b> 114, the system control unit 50 determines whether or not the memory 30 has an image storage buffer area capable of storing captured image data. As a result of this determination, if there is no area where new image data can be stored in the image storage buffer area of the memory 30, the process proceeds to step S 115, and a predetermined warning is given by image or sound using the notification unit 54. Thereafter, the process returns to step S102.

  Here, the case where there is no area where new image data can be stored in the image storage buffer area of the memory 30 can be considered as follows. Immediately after performing the maximum number of continuous shots that can be stored in the image storage buffer area of the memory 30, the first image data to be read from the memory 30 and recorded in the storage medium 200 or 210 is still a storage medium. In 200 or 210, the recording may not be completed. In such a case, one empty area cannot be secured in the image storage buffer area of the memory 30.

  When the image data of the captured image is compressed and then stored in the image storage buffer area of the memory 30, it is necessary to consider that the amount of image data after compression varies depending on the compression mode setting. In step S114, it is determined whether or not a storable area is on the image storage buffer area of the memory 30 in consideration of this.

  If it is determined in step S114 that there is an area where new image data can be stored in the memory 30, the process proceeds to step S116.

In step S116, the system control unit 50 executes shooting processing.
In this photographing process, first, an electrical signal (imaging signal) based on the charge accumulated for a predetermined time is read from the imaging element 14. Then, the image data based on the processed electric signal through the A / D converter 16, the image processing circuit unit 20, the memory control circuit unit 22, or directly from the A / D converter 16 through the memory control circuit unit 22. Is stored in a predetermined area of the memory 30. Note that the imaging process performed here will be described later in detail with reference to FIGS. 7 and 8.

  Subsequently, in step S <b> 117, the system control unit 50 performs development processing of the image data stored in the predetermined area of the memory 30. Hereinafter, specific processing in step S117 will be described.

  First, the system control unit 50 reads out part of the image data (the central part of the light receiving unit 141 and the light shielding unit (OB unit) 142) stored in a predetermined area of the memory 30 via the memory control circuit unit 22. WB integration calculation processing and OB (optical black) integration calculation processing necessary for performing the development processing are performed. Then, the system control unit 50 stores these calculation results in the internal memory or the memory 52 of the system control unit 50. Further, the system control unit 50 reads out image data written in a predetermined area of the memory 30 using the memory control circuit unit 22 and, if necessary, the image processing circuit unit 20. The read image data is subjected to various development processes including an AWB process, a gamma conversion process, and a color conversion process using the calculation result stored in the internal memory of the system control unit 50 or the memory 52. At this time, correction data is generated using standard shading data stored in advance with standard timing settings, and known shading correction is also performed. Then, the system control unit 50 stores the developed image data in a predetermined area of the memory 30.

  Subsequently, in step S118, the system control unit 50 reads out image data stored in a predetermined area of the memory 30, and the compression / decompression circuit unit 32 performs image compression processing according to the set mode. Then, image data that has been shot and finished a series of processing is written into the empty image portion of the image storage buffer area of the memory 30.

  Subsequently, in step S119, the system control unit 50 reads processed image data stored in the image storage buffer area of the memory 30. Then, the system control unit 50 performs a recording process for writing the read image data to the recording medium 200 or 210 such as a memory card or a compact flash (registered trademark) card via the interface 90 or 94 and the connector 92 or 96. To start. This recording start process is performed on the image data every time new image data that has been shot and finished a series of processes is newly written in the empty image portion of the image storage buffer area of the memory 30.

  Note that while the image data is being written to the recording media 200 and 210, a recording medium writing operation display such as blinking an LED is performed on the notification unit 54 to indicate that the writing operation is being performed.

  Subsequently, the system control unit 50 determines whether or not the first shutter switch (SW1) 62 has been pressed and is in an ON state (step S120). If the result of this determination is that the first shutter switch (SW1) 62 has been released and is in the OFF state (step S120 / NO), the processing returns to step S102. On the other hand, if the result of determination in step S120 is that the first shutter switch (SW1) 62 has been pressed and is in an ON state (step S120 / YES), the process returns to step S112 to prepare for the next shooting.

Next, the photographing process performed in step S116 in FIG. 6 will be described with reference to the flowcharts in FIGS.
7 and 8 are flowcharts showing the detailed processing procedure of the photographing process in step S116 of FIG. In this photographing process, various signals are exchanged between the system control unit 50 and the aperture control unit 340 or the focus control unit 342 via the interface 120, the connectors 122 and 322, the interface 320, and the lens system control unit 350. Is called.

  First, the system control unit 50 moves the mirror 130 to the mirror up position by a mirror driving unit (not shown) (step S201).

  Subsequently, the system control unit 50 drives the aperture 312 to a predetermined aperture value by the aperture control unit 340 in accordance with the photometric data stored in the internal memory of the system control unit 50 or the memory 52 (step S202).

  Subsequently, the system control unit 50 performs a clear operation of charges accumulated in each pixel of the image sensor 14 (step S203).

  Subsequently, when the charge clear operation in step S203 is completed, the system control unit 50 sets the state of the image sensor 14 to a state in which charge accumulation is started (step S204).

  Subsequently, the system control unit 50 opens the shutter 12 by the shutter control unit 40 (step S205), and starts exposure of the image sensor 14 (step S206).

  Subsequently, the system control unit 50 checks (detects) the flash flag and determines whether or not the flash unit 48 needs to emit light (step S207). As a result of the determination, if the flash unit 48 needs to emit light (step S207 / YES), the system control unit 50 performs the light emission process of the flash unit 48 (step S208). Thereafter, the process proceeds to step S209.

  On the other hand, if the result of determination in step S207 is that the flash flag is not set and light emission by the flash unit 48 is not necessary (step S207 / NO), the process proceeds to step S209.

  In step S209, the system control unit 50 waits for the end of exposure of the image sensor 14 according to the photometric data. When the exposure ends (step S209 / YES), the process proceeds to step S210. The system control unit 50 closes the shutter 12 by the shutter control unit 40 (step S210), and the exposure of the image sensor 14 ends.

  Subsequently, the system control unit 50 drives the aperture 312 to the open aperture value by the aperture control unit 340 (step S211), and moves the mirror 130 to the mirror down position by the mirror drive unit (not shown) (step S212). .

  Subsequently, the system control unit 50 determines whether or not the set charge accumulation time has elapsed (step S213). When the set charge accumulation time has elapsed (step S213 / YES), the system control unit 50 ends the charge accumulation of the image sensor 14 (step S214).

  Subsequently, in step S215 in FIG. 8, the system control unit 50 reads the ADCLK signal of the A / D converter 16 by the timing generation circuit unit 18 before reading out the electrical signal (imaging signal) based on the charge from the imaging device 14. The sampling timing is set to a predetermined value T1.

  Subsequently, the system control unit 50 is a pixel located in the uppermost row among the pixels configured on the imaging surface of the imaging device 14 illustrated in FIG. 2, that is, the light shielding unit (OB unit) of the imaging device 14. Control is performed to read out the imaging signals in the pixels in the first row 142 (step S216). At this time, based on the control by the system control unit 50, the timing generation circuit unit 18 reads out the imaging signal from the pixels in the first row of the light shielding unit (OB unit) 142 of the imaging device 14 and samples at the sampling timing T1. Do. Through these processes, the image processing circuit unit 20 reads out the imaging signal in the pixels in the first row of the light shielding unit (OB unit) 142 of the imaging device 14 via the A / D converter 16.

  Subsequently, the image processing circuit unit 20 creates first shading data (SHDT1) from the imaging signals of the pixels in the first row read out in step S216 based on the control by the system control unit 50 (step S217). ). Thereafter, the system control unit 50 temporarily stores the first shading data (SHDT1) created by the image processing circuit unit 20 in the memory 52.

  Subsequently, the system control unit 50 determines whether or not the number of rows of the imaging signal in each pixel read from the imaging device 14 has reached a predetermined number of rows (10 rows in the present embodiment) (step). S218). That is, in step S218, the image pickup signal is read out from the pixels formed on the image pickup surface of the image pickup device 14 shown in FIG. Judge whether or not.

  As a result of the determination in step S218, when the number of rows of the imaging signal in each pixel read from the imaging device 14 has not reached 10, the process proceeds to step S219. In step S219, the system control unit 50 sets the sampling timing (+1 setting) delayed by the minimum predetermined interval time (1 tap) that can be set in the timing generation circuit unit 18 with respect to the currently set sampling timing. Do.

  Subsequently, the system control unit 50 performs control to read out the row from which the imaging signal is read from the imaging device 14 by shifting the row from the current setting row by +1 (step S220). At this time, based on the control by the system control unit 50, the timing generation circuit unit 18 sets the readout of the imaging signal in the pixel on the Nth row (N is an integer equal to or less than 10) shifted by +1 row in step S219. Sampling is performed at the sampling timing. By these processes, the image processing circuit unit 20 reads out the image pickup signal at the pixel in the Nth row of the light shielding unit (OB unit) 142 of the image pickup device 14 via the A / D converter 16.

  Subsequently, based on the control by the system control unit 50, the image processing circuit unit 20 creates the Nth shading data (SHDTN) from the imaging signals of the pixels for one row read in step S220 (step S221). ). Thereafter, the system control unit 50 temporarily stores the Nth shading data (SHDTN) in the memory 52. Then, the process returns to step S218. In the present embodiment, steps S219 to S221 are repeated until the imaging signals in the pixels for 10 rows from the top of the light shielding unit (OB unit) 142 of the imaging device 14 are read.

  Through steps S215 to S221, the timing generation circuit unit (sampling unit) 18 outputs an imaging signal from a pixel in the light shielding unit 142, which is a partial region on the imaging surface of the imaging device 14, at a plurality of sampling timings. Sampling is performed. At this time, when the timing generation circuit 18 samples an imaging signal from a pixel in the light shielding unit 142 which is a partial region on the imaging surface of the imaging element 14, the timing generation circuit unit 18 in the horizontal direction formed on the imaging surface. The sampling timing is changed for each row of pixels. The image processing circuit unit (creating unit) 20 calculates shading for each sampling timing based on the imaging signals respectively obtained from the imaging element 14 in accordance with a plurality of sampling timings by the timing generation circuit unit 18 and performs shading. Create data.

  The sampling timing T1 is set to a timing that is earlier than the standard sampling timing, and a sampling timing that is before or after the standard sampling timing is set from the sampling timing T1 to T10. The number of rows to be read set in step S218 is 10 rows in the present embodiment shown in FIG. 8, but the present invention is not limited to this. The number of rows to be read set in step S218 is the number of rows that can be set by the number of rows of the light shielding unit (OB unit) 142 included in the image sensor 14 and the number of taps that can be set in the timing generation circuit unit 18. It can be changed within the range.

  As a result of the determination in step S218, when the number of rows of the imaging signal in each pixel read from the imaging device 14 has reached 10, the process proceeds to step S222. In step S222, the system control unit 50 firstly includes standard shading data stored in advance in the non-volatile memory (storage means) 56 and a plurality of shading data generated through steps S215 to S221 and stored in the memory 52. Compare with. Then, the system control unit 50 extracts shading data that minimizes the difference from the standard shading data among the plurality of shading data for each sampling timing created by the image processing circuit unit 20 (extraction means).

  Subsequently, the system control unit 50 sets the sampling timing in the shading data extracted in step S222 to the timing generation circuit unit 18 (step S223).

  Subsequently, the system control unit 50 performs control to read out the imaging signals of the respective pixels in the eleventh and subsequent rows from the imaging device 14 (step S224). At this time, based on the control by the system control unit 50, the timing generation circuit unit 18 reads the imaging signals of the respective pixels in the eleventh and subsequent rows at the sampling timing set in step S223. In step S224, A / D conversion is performed on the imaging signal of each pixel and the imaging signals of all pixels in the light receiving unit 141 in the 11th and subsequent rows of the light shielding unit (OB unit) 142 illustrated in FIG. 2 at the sampling timing set in step S223. The data is read by the device 16.

  Then, the image pickup signal read in step S224 is sent to the memory control circuit unit 22 via the A / D converter 16, the image processing circuit unit 20, the memory control circuit unit 22, or directly from the A / D converter 16. The data is written into a predetermined area of the memory 30 via the.

  Through the processing in steps S223 and S224, the system control unit 50 captures images from pixels in the light receiving unit 141 that is at least a region other than the light shielding unit (OB unit) 142 that is a partial region on the imaging surface of the image sensor 14. Control is performed to cause the timing generation circuit unit 18 to sample the signal at the sampling timing in the shading data extracted in step S222 (control means).

  When a series of processes from step S201 to S224 is completed, the photographing process is terminated, and the process proceeds to the development process shown in FIG.

  In the present embodiment, only one row is set and read at one sampling timing, but the present invention is not limited to this, and a plurality of rows are read at the same sampling timing. You may make it come out. In this case, one piece of shading data is created based on the imaging signals of a plurality of rows read at the same sampling timing, and shading data is created for each of the plurality of rows.

  In the present embodiment, horizontal shading is performed in which shading is performed using shading data based on the imaging signal read out from the imaging device 14 in units of rows. However, the present invention is not limited to this, and depending on the characteristics of the image sensor 14, vertical shading is performed in which shading is performed using shading data based on the image signal read from the image sensor 14 in units of columns. May be.

  In the present embodiment, an example in which the imaging element 14 is configured by a CMOS area sensor has been described. However, the imaging element 14 is not limited thereto, and is configured by, for example, a CCD area sensor or the like. It may be.

  In the imaging apparatus of the present embodiment, the sampling timing in the shading data that minimizes the difference from the standard shading data is selected, and the imaging signal of the light receiving unit 141 used for the image data is obtained at the sampling timing. As a result, even if the output delay of the image sensor 14 due to an environmental change such as a temperature change occurs, the sampling point for the output is set to a sampling timing that is not different from the standard setting, so that the image data is stabilized. Can be generated.

  Each unit of FIG. 1 constituting the imaging apparatus according to the embodiment of the present invention described above, and each step of FIGS. 5 to 8 showing the driving method of the imaging apparatus is stored in a RAM or a ROM of a computer. This can be realized by operating the program. This program and a computer-readable storage medium storing the program are included in the present invention.

  Specifically, the program is recorded in a storage medium such as a CD-ROM, or provided to a computer via various transmission media. As a storage medium for recording the program, a flexible disk, a hard disk, a magnetic tape, a magneto-optical disk, a nonvolatile memory card, and the like can be used in addition to the CD-ROM. On the other hand, as the transmission medium of the program, a communication medium in a computer network (LAN, WAN such as the Internet, wireless communication network, etc.) system for propagating and supplying program information as a carrier wave can be used. Moreover, examples of the communication medium at this time include a wired line such as an optical fiber, a wireless line, and the like.

  In addition, the function of the imaging apparatus according to the embodiment of the present invention is realized by executing a program supplied by the computer, and an OS (operating system) or other program running on the computer. When the functions of the imaging apparatus according to the embodiment of the present invention are realized in cooperation with application software, etc., or all or part of the processing of the supplied program is performed by a function expansion board or function expansion unit of the computer. Even when the functions of the imaging apparatus according to the embodiment of the present invention are realized, such a program is included in the present invention.

1 is a block diagram illustrating a schematic configuration of an imaging apparatus according to an embodiment of the present invention. It is a schematic diagram which shows the structure in the imaging surface of an image pick-up element. It is a characteristic view which shows the characteristic of an image pick-up element. It is a timing chart which shows each control signal from a timing generation circuit part, and an analog signal (imaging signal) output from an image sensor. 3 is a flowchart illustrating a method for driving the imaging apparatus according to the present embodiment. FIG. 6 is a flowchart illustrating a driving method of the imaging apparatus according to the present embodiment, following FIG. 5. It is a flowchart which shows the detailed process sequence of the imaging | photography process in FIG.6 S116. FIG. 8 is a flowchart illustrating a detailed processing procedure of the photographing process in step S <b> 116 in FIG. 6 following FIG. 7.

Explanation of symbols

12 Shutter 14 (Solid State) Image Sensor 16 A / D Converter 18 Timing Generation Circuit Unit 20 Image Processing Circuit Unit 22 Memory Control Circuit Unit 24 Image Display Memory 26 D / A Converter 28 Image Display Unit 30 Memory 32 Compression / Expansion Circuit Unit 40 shutter control unit 42 distance measurement control unit 46 photometry control unit 48 flash unit 50 system control unit 52 memory 54 notification unit 56 non-volatile memory 60 mode dial switch 62 first shutter switch (SW1)
64 Second shutter switch (SW2)
66 Playback switch 70 Operation unit 72 Power switch 80 Power control unit 82, 84 Connector 86 Power supply 90, 94 Interface (I / F)
92, 96 Connector 98 Recording medium attachment / detachment detection unit 100 Camera body 104 Optical viewfinder 106 Lens mount 110 Communication unit 120 Interface (I / F)
122 Connector 130, 132 Mirror 200, 210 Recording medium 202, 212 Recording unit 204, 214 Interface (I / F)
206, 216 Connector 300 Lens unit 306 Lens mount 310 Imaging lens 312 Aperture 320 Interface (I / F)
322 Connector 340 Aperture controller 342 Focus controller 344 Zoom controller 350 Lens system controller

Claims (4)

An image pickup device having pixels arranged in a two-dimensional matrix on the image pickup surface;
Sampling means for sampling an imaging signal from a pixel in a partial area on the imaging surface of the imaging device at a plurality of sampling timings;
Creating means for calculating shading and creating shading data for each sampling timing based on the imaging signals obtained from the imaging elements according to the plurality of sampling timings by the sampling means;
Storage means for storing standard shading data at a standard sampling timing as a standard;
Extracting means for extracting shading data that minimizes the difference from the standard shading data among the plurality of shading data for each sampling timing created by the creating means;
Control means for performing control to cause the sampling means to sample an image pickup signal from a pixel in an area other than the partial area on the imaging surface at a sampling timing in the shading data extracted by the extraction means. An imaging device that is characterized.   The imaging apparatus according to claim 1, wherein the partial area on the imaging surface includes at least a horizontal line of pixels formed on the imaging surface.   The sampling means changes a sampling timing for each pixel in one horizontal row formed on the imaging surface when sampling an imaging signal from a pixel in the partial area on the imaging surface. The imaging apparatus according to claim 1. Sampling for sampling an imaging element having pixels arranged in a two-dimensional matrix on an imaging surface, and imaging signals from pixels in a partial area of the imaging surface of the imaging element at a plurality of sampling timings A driving method of an imaging apparatus comprising: means and storage means for storing standard shading data at a standard sampling timing as a standard,
A step of calculating shading and creating shading data for each sampling timing based on imaging signals respectively obtained from the imaging elements according to the plurality of sampling timings by the sampling means;
Extracting the shading data that minimizes the difference from the standard shading data from among the plurality of shading data for each of the created sampling timings;
And a step of controlling the sampling means to sample an imaging signal from a pixel in a region other than the partial region on the imaging surface at a sampling timing in the extracted shading data. Driving method.

Images