JP5921092B2 - Imaging device, control method thereof, and control program - Google Patents

Description

  The present invention relates to an image pickup apparatus having an image pickup element such as a CCD and a CMOS image sensor, and more particularly to a method for driving the image pickup element.

  In general, in an imaging apparatus such as a digital camera, a solid-state image sensor such as a CCD or a CMOS image sensor is used, and a still image or a moving image captured by the solid-state image sensor is recorded and reproduced. For example, in an image pickup apparatus using a CMOS image sensor, a charge generated according to an optical image in a photodiode of the CMOS image sensor is converted into a signal voltage by a readout circuit at the time of shooting, and then the voltage signal is amplified. Output from the output terminal.

  In such an imaging apparatus, various noises that cause image quality degradation of the image are generated in the process of converting an optical image into an electrical signal by the imaging element. Typical noise includes noise due to pixel defects caused by manufacturing variations for each pixel, and fixed pattern noises caused by manufacturing variations of components such as an amplifier constituting the readout circuit.

  Furthermore, random noise that changes every time an imaging operation such as reset noise of pixels and readout circuits and dark current generated in the pixel region is performed is also known as typical noise.

  The following “SN operation” is known as a technique for removing the noise as described above inside the image sensor (see, for example, Patent Document 1).

  In the “SN operation”, after resetting the photodiode in the pixel, the image sensor is exposed to perform photoelectric conversion and charge accumulation in the photodiode. Then, in accordance with the timing when the exposure of the image sensor is completed, the photodiode rear-stage circuit (hereinafter referred to as the rear-stage circuit) and the readout circuit in the pixel are reset except for the photodiode.

  When the reset is completed, the pixel signal at the time of resetting is transferred to the first line memory provided in the readout circuit as a noise component in a state where the charge accumulated in the photodiode is not output to the subsequent circuit, and The noise component is held in the first line memory (hereinafter, the noise signal is referred to as “N signal” and the N signal transfer operation is referred to as “N transfer”).

Subsequently, the charge accumulated in the photodiode is output to the subsequent circuit. At this time, the pixel signal is transferred as an optical signal to a second line memory provided in the readout circuit, and the optical signal is held in the second line memory (hereinafter, the optical signal is referred to as “S signal”, and S Signal transfer is called “S transfer”.)
After the S transfer is completed, the S signal held in the second line memory and the N signal held in the first line memory are sequentially sent to the last differential amplifier. Finally, the difference between the S signal and the N signal is obtained by the differential amplifier, and the difference is output as an image signal from the output terminal of the image sensor to the subsequent image processing circuit.

  Among the above operations, N transfer, S transfer, and difference calculation (differential operation) in the differential amplifier are referred to as the above-described “SN operation”.

  By performing the “S-N operation” described above, it is possible to appropriately remove noise components that differ for each pixel and readout circuit, and obtain an image signal with good image quality.

JP 2004-134752 A

  However, when the above-described SN operation is performed, a new noise component may be generated and the image quality may be deteriorated. If the power supply and the ground level (GND level) of the image sensor are stable until the timing at which the N transfer is started and the S transfer is completed, the noise component is removed without excess or short by performing the SN operation. be able to.

  However, when the power supply or GND level of the image sensor fluctuates at each timing of N transfer and S transfer, the reference voltage differs between N transfer and S transfer. As a result, the fluctuation amount of the reference voltage of each of the N signal and the S signal appears as an offset error.

  When the SN operation is performed in this state, the difference between the offset superimposed on the N signal and the offset superimposed on the S signal appears as new noise in the image signal, and the image quality deteriorates.

  In general, since the “SN operation” is performed at the same timing with respect to the signals of the pixel groups arranged in the same pixel row, the noise due to the offset difference as described above is in the form of horizontal stripes in the image. Appears as pattern noise.

  Accordingly, an object of the present invention is to provide an imaging apparatus, a control method thereof, and a control program that can suppress image quality degradation caused by fluctuations in the power supply or GND level of the imaging element.

In order to achieve the above object, an imaging apparatus according to the present invention includes a plurality of unit pixels arranged in a two-dimensional matrix, a readout unit that reads out an optical signal and a noise signal in units of rows from the unit pixels, and the optical signal. A plurality of drive patterns in which an image pickup device including a difference signal output unit that outputs a difference from the noise signal as an image signal and at least one of the optical signal and the noise signal read by the reading unit are different from each other If the memory means for storing, noise source to vary the power supply voltage of the image sensor is determined whether the electrically driven, the noise source is determined to be electrically driven, A control pattern corresponding to the noise source is selected from the memory means, and readout control of the image sensor is performed with the selected drive pattern. And having a means.

According to the control method of the present invention, a plurality of unit pixels are arranged in a two-dimensional matrix, a reading unit that reads out an optical signal and a noise signal in units of rows from the unit pixel, and a difference between the optical signal and the noise signal is imaged. An image pickup device including a differential signal output unit that outputs a signal; and a memory unit that stores a plurality of drive patterns having different readout timings of at least one of the optical signal and the noise signal by the readout unit. A control method for controlling an image pickup apparatus, wherein a determination step for determining whether or not a noise source that fluctuates a power supply voltage of the image pickup device is electrically driven, and the noise source is electrically connected in the determination step. to when it is determined to be driven, a driving pattern corresponding to the noise source from said memory means Characterized in that it has a selection step of-option, and a control step of driving pattern selected in said selecting step controls reading of the image sensor.

According to the control program of the present invention, a plurality of unit pixels are arranged in a two-dimensional matrix, a reading unit that reads out an optical signal and a noise signal from the unit pixel in units of rows, and a difference between the optical signal and the noise signal is imaged. An image pickup device including a differential signal output unit that outputs a signal; and a memory unit that stores a plurality of drive patterns having different readout timings of at least one of the optical signal and the noise signal by the readout unit. a control program for controlling the imaging apparatus, the computer in which the imaging device comprises, a determination step noise source for varying the power supply voltage whether or not it is electrically driven in the imaging device, wherein When it is determined in the determination step that the noise source is electrically driven, the method A selection step of selecting a driving pattern corresponding to the noise source from Li means, characterized in that to execute a control step of driving pattern selected in said selecting step controls reading of the image sensor.

  According to the present invention, there is an effect that image quality deterioration due to fluctuations in the power supply of the image sensor and the GND level can be suppressed.

It is a block diagram which shows the structure of an example of the imaging device by embodiment of this invention. It is a figure which shows the equivalent circuit of the solid-state image sensor shown in FIG. It is a figure which shows the 1st example of the drive pattern for demonstrating the signal read-out operation | movement in the solid-state image sensor shown in FIG. It is a figure which shows the 2nd example of the drive pattern for demonstrating the signal read-out operation | movement in the solid-state image sensor shown in FIG. It is a figure which shows the 3rd example of the drive pattern for demonstrating the signal read-out operation | movement in the solid-state image sensor shown in FIG. It is a figure which shows the 4th example of the drive pattern for demonstrating the signal read-out operation | movement in the solid-state image sensor shown in FIG. It is a figure for demonstrating an example of the determination of the timing which determines the signal level of an optical signal (S signal) and a noise signal (N signal). It is a figure for demonstrating the other example of the determination of the timing which determines the signal level of an optical signal (S signal) and a noise signal (N signal). It is a figure for demonstrating an example of the relationship between the drive pattern which drives the solid-state image sensor shown in FIG. 2, and the various apparatuses which are noise sources. It is a figure for demonstrating an example of the method of calculating | requiring the period of the horizontal stripe noise demonstrated in relation to FIG. 3 is a flowchart for explaining an example of drive pattern selection in the imaging apparatus shown in FIG. 1 (part 1); 6 is a flowchart for explaining an example of drive pattern selection in the imaging apparatus shown in FIG. 1 (part 2); It is a figure which shows the example of the shading correction data for every drive pattern in the 1st Embodiment of this invention. It is a figure which shows the correction | amendment for every read-out line in the 1st Embodiment of this invention. It is a figure which shows an example of arrangement | positioning of the imaging area and light-shielding area | region of a solid-state image sensor in the 1st Embodiment of this invention. It is a figure which shows an example of selection of the drive pattern at the time of reading out about the light-shielding pixel area | region in the 1st Embodiment of this invention. It is a flowchart for demonstrating an example of the selection of the drive pattern in the imaging device by the 2nd Embodiment of this invention (the 1). It is a flowchart for demonstrating an example of the selection of the drive pattern in the imaging device by the 2nd Embodiment of this invention (the 2).

  Hereinafter, an example of an imaging apparatus according to an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 is a block diagram showing a configuration of an example of an imaging apparatus according to an embodiment of the present invention.

  The imaging apparatus illustrated in FIG. 1 has a solid-state imaging element 303. The lens 301 forms an optical image of the subject on the solid-state image sensor 303. The diaphragm 302 changes the amount of light that has passed through the lens 301. The solid-state image sensor 303 converts an optical image into an electrical signal (image signal) by photoelectric conversion and outputs the electrical signal.

  An image signal (also referred to as an imaging signal) output from the solid-state imaging element 303 is supplied to the imaging signal processing circuit 304. The imaging signal processing circuit 304 has a variable gain amplifier for amplifying the image signal and a gain correction circuit for correcting the gain value. The image signal output from the imaging signal processing circuit 304 is A / D converted by an analog-digital (A / D) conversion unit 305 and supplied to the signal processing unit 306 as image data.

  The signal processing unit 306 performs various corrections on the image data output from the A / D conversion unit 305 and performs data compression as necessary. Various timing pulses are supplied from the timing generation unit 313 to the solid-state imaging device 303, the imaging signal processing circuit 304, the A / D conversion unit 305, and the signal processing unit 306.

  The overall control / calculation unit 312 performs various calculations and controls the imaging apparatus. Image data is temporarily stored in the memory unit 307 (memory means). The external interface (I / F) unit 310 communicates with an external device 311 such as an external computer, for example. Note that the external I / F 310 can wirelessly communicate with the external device 311 such as transmitting image data via the wireless unit 318.

  A recording medium 309 can be attached to and detached from the recording medium control interface (I / F) unit 308. When the recording medium 309 is attached to the recording medium control I / F 308, image data is recorded on and read from the recording medium 309 by the recording medium control I / F 308. Note that the recording medium 309 is composed of, for example, a semiconductor memory.

  The strobe unit 314 performs AF (autofocus) auxiliary light projection and flash light control. The power supply circuit 315 includes a DC / DC circuit that converts a voltage supplied from a battery or the like into a desired voltage, and supplies a voltage necessary for the imaging apparatus to each unit including the recording medium 309 for a necessary period. The lens barrel of the lens 301 is driven by a motor 316 under the control of the overall control / arithmetic unit 312, and the diaphragm 302 is driven by a motor 317.

  In the imaging apparatus shown in FIG. 1, as described above, a device such as a strobe, a DC / DC circuit for performing voltage conversion, a motor for driving a lens barrel and a diaphragm, and an external device such as a PC A communication unit or the like for performing communication is provided. That is, the imaging apparatus has many elements that can be a noise source that fluctuates the power supply voltage of the imaging element in or near the imaging apparatus. When these noise sources operate during signal readout of the image sensor, the power supply voltage supplied to the image sensor becomes unstable due to power fluctuations and electromagnetic waves.

  Since these noise sources generate an electromagnetic wave having a specific frequency for each device and component, the power supply voltage of the image sensor varies periodically, and the noise appears in the image as periodic horizontal stripes.

  Furthermore, since the power supply voltage of the image sensor fluctuates with a different period for each noise source, the period of the horizontal stripe noise that appears in the image differs depending on which device is operating when reading the signal of the image sensor.

  In addition to the devices and components shown in FIG. 1, devices and components that can change the power supply of the imaging apparatus and the magnetic field around the imaging element by operation are considered to be noise sources.

  FIG. 2 is a diagram showing an equivalent circuit of the solid-state imaging device 303 shown in FIG.

  Referring to FIG. 2, each circuit element constituting solid-state imaging element 303 is formed on one semiconductor substrate such as single crystal silicon by a semiconductor integrated circuit manufacturing technique. Here, the number of rows and the number of columns of the pixel array are assumed to be n rows × m columns (each of n and m is an integer of 2 or more). In the illustrated example, a pixel array of 3 rows × 3 columns with n = m = 3 is shown, but the number of rows and columns of the pixel array is not limited to the illustrated example.

  The solid-state imaging device has a plurality of unit pixels 400 arranged in a two-dimensional matrix, and a pixel unit is configured by these unit pixels 400. The unit pixel 400 includes a photodiode PD, and the photodiode PD receives light and generates an optical signal that is an electrical signal. In the illustrated example, the anode of the photodiode PD is grounded.

  The cathode of the photodiode PD is connected to the gate of the amplification MOS M3 through the transfer MOS M1 for transferring the optical signal charge accumulated in the photodiode PD. The gate of the amplification MOS M3 is connected to the source of the reset MOS M2 for resetting the amplification MOS M3, and the drain of the reset MOS M2 is connected to the reset power source. The drain of the amplification MOS M3 is directly connected to the power supply.

  The gate of the transfer MOS M1 of the unit pixel 400 in the n-th row is connected to a row transfer line PTX_n arranged extending in the horizontal direction. In addition, the gate of the reset MOS M2 of the unit pixel 400 in the n-th row is connected to a row reset line PRES_n arranged extending in the horizontal direction. The gate of the selection MOS M4 of the unit pixel 400 in the n-th row is connected to a row selection line PSEL_n arranged extending in the horizontal direction.

  The row transfer line PTX_n, the row reset line PRES_n, and the row selection line PSEL_n are connected to a vertical scanning circuit (VSR) block 411.

  The row transfer line PTX_n is supplied with a signal voltage generated by the vertical scanning circuit block 411 for controlling the transfer of the pixel signal at a timing described later. A signal voltage generated by the vertical scanning circuit block 411 and used to control the reset of the unit pixel 400 is supplied to the row reset line PRES_n at a timing described later. The row selection line PSEL_n is supplied with a signal voltage for selecting a pixel row generated by the vertical scanning circuit block 411 and performing signal transfer at a timing described later.

  The source of the amplification MOS M3 of the m-th column unit pixel 400 is connected via a selection MOS M4 to a vertical signal line V_m arranged extending in the vertical direction. The vertical signal line V_m is connected to the constant current source I which is a load means and is connected to the clamp capacitor C0. The clamp capacitor C0 is connected to the inverting terminal of the operational amplifier 401.

  The non-inverting terminal of the operational amplifier 401 is connected to the clamp voltage VC0R (VREF). The output terminal of the operational amplifier 401 is connected to a capacitor CTN_m (second holding means) for temporarily holding the noise signal (reference signal of the imaging signal) via the noise signal transfer switch M11. The output terminal of the operational amplifier 401 is connected to a capacitor CTS_m (first holding means) for temporarily holding the optical signal (imaging signal) via the optical signal transfer switch M12.

  The terminals on the opposite sides of the noise signal holding capacitor CTN_m and the optical signal holding capacitor CTS_m are grounded. The connection point between the noise signal transfer switch M11 and the noise signal holding capacitor CTN_m and the connection point between the optical signal transfer switch M12 and the optical signal holding capacitor CTS_m are connected to the optical signal via the horizontal transfer switch M21 and the horizontal transfer switch M22, respectively. It is connected to a differential circuit block 431 (difference signal output means) for obtaining a difference from the noise signal. Read circuits are similarly provided for the remaining vertical signal lines V_m−1 and V_m + 1 shown in FIG.

  The gates of the noise signal transfer switches M11 in each column are commonly connected to the first transfer signal input terminal PTN. The gates of the optical signal transfer switches M12 in each column are connected in common to the second transfer signal input terminal PTS. Signal voltages are respectively supplied to the first transfer signal input terminal PTN and the second transfer signal input terminal PTS at a timing described later.

  The gates of the horizontal transfer switch M21 and the horizontal transfer switch M22 in the m-th column are connected to the horizontal scanning circuit (HSR) block 421 through the column selection line PH_m. The column selection lines PH_m−1 and PH_m + 1 are configured in the same manner.

  FIG. 3 is a diagram illustrating a first example of a drive pattern for explaining a signal reading operation in the solid-state imaging device 303 illustrated in FIG. 2.

  When the signal reading in the image sensor 303 is performed, it starts from the 0th row and is performed in the order of the 1st row, the 2nd row, and the 3rd row. Then, after the signal reading operation for the corresponding row is completed, the operation proceeds to the reading operation for the next row.

  Here, with reference to FIG. 2 and FIG. 3, focusing on the n-th row of the solid-state imaging device 303, the reading operation will be described.

  Now, at time T0, when the row selection pulse PSEL becomes low level (L level), the pixel selection MOS M4 in the row read immediately before, that is, the (n−1) th row is turned off, and (n -1) The selection of the unit pixel 400 in the row is canceled. At the same time, the clamp pulse PC0R becomes high level (H level), and resetting of the clamp capacitor C0 is started. Further, the transfer signal input pulses PTS and PTN become H level, and resetting of the noise signal holding capacitor CTN and the optical signal holding capacitor CTS is started.

  When a line feed pulse PV (not shown) is input to the vertical scanning circuit (VSR) 411 at time T1, the line feed of the selected line to be read is performed. Here, the selected row is sent from the (n-1) th row to the nth row.

  At time T2, the row reset pulse PRES becomes L level, the reset of the FD is released, and the reference potential of the floating diffusion FD is determined.

  At time T3, the line feed pulse PV becomes H level. Further, the row selection pulse PSEL becomes H level, the pixel selection MOS M4 is turned on, and the unit pixel 400 in the nth row is selected.

  At time T4, the transfer signal input pulses PTS and PTN become L level, the resetting of the optical signal holding capacitor CTS and the noise signal holding capacitor CTN is completed, and the reference potentials of CTS and CTN are determined.

  At time T5, the clamp pulse PC0R becomes L level, and the reference potential VC0R is held in the capacitor C0.

  At time T6, the transfer signal input pulse PTN becomes H level, and the potential (voltage) of the floating diffusion FD is output to the noise signal holding capacitor CTN.

  At time T7, the transfer signal input pulse PTN becomes L level (holding timing), and the potential (voltage) of the floating diffusion FD at this time is held in the noise signal holding capacitor CTN as a noise signal (reference signal of the imaging signal).

  At time T8, the transfer signal input pulse PTS becomes H level, and the potential (voltage) of the floating diffusion FD is output to the optical signal holding capacitor CTS.

  At time T9, while the transfer signal input pulse PTS is at the H level, the row transfer line PTX is at the H level, the transfer MOS M1 is turned on, and the charge accumulated in the photodiode PD is transferred to the floating diffusion FD. The

  At time T10, the row transfer line PTX becomes L level, the transfer MOS M1 is turned off, and the transfer of charges to the floating diffusion FD is completed.

  At time T11, the transfer signal input pulse PTS becomes L level, and the potential of the floating diffusion FD at this time is held in the optical signal holding capacitor CTS as an optical signal (imaging signal).

  At time T12, the row reset pulse PRES becomes H level, and resetting of the floating diffusion FD is started.

  When a column feed pulse PH (not shown) is input to the horizontal scanning circuit (HSR) 421 at time T13, column transfer pulses are sequentially input to the column selection line PH from the first column to the last column in the readout area. . Therefore, the signals held in the optical signal holding capacitor CTS and the noise signal holding capacitor CTN are sent to the differential circuit block 431 in order of one column. Then, the differential circuit block 431 outputs a differential amplified signal between the optical signal and the noise signal as an image signal from the output terminal of the solid-state imaging device 303.

  The above is the signal readout operation of the nth pixel row, which is defined as one horizontal period.

  After the readout of the pixel signal of the nth row is completed, the operation moves to the readout operation of the (n + 1) th row. In addition, regarding the readout of the pixel rows other than the nth row, the readout operation similar to that of the nth row is repeated, and when the signal readout of each row is completed, the process proceeds to readout of the next row.

  The above-described operation is repeated until the signal readout of all the pixel rows included in the solid-state image sensor 303 is completed, and an image signal for one frame is read out.

(First embodiment)
Here, the first embodiment of the imaging apparatus described above will be described. The imaging apparatus according to the first embodiment stores at least two types of the drive patterns described above. Then, a drive pattern is selected in accordance with conditions at the time of driving the imaging device, and an image signal is read out.

  In the following description, a case where four types of noise sources are included in the imaging apparatus or in the connected device will be described as an example. However, the number of noise sources is not limited to four. Here, the type of noise source and the operating state of each noise source are determined every time one frame is read. Then, a noise source that has a large influence on the image signal among the noise sources that are operating when the image signal is read is prioritized, and a drive pattern is selected according to the noise source.

  FIG. 4 is a diagram illustrating a second example of a driving pattern for explaining a signal reading operation in the solid-state imaging device 303 illustrated in FIG. 2. FIG. 5 is a diagram showing a third example of a drive pattern for explaining a signal readout operation in the solid-state imaging device 303 shown in FIG. FIG. 6 is a diagram illustrating a fourth example of a driving pattern for explaining a signal reading operation in the solid-state imaging device 303 illustrated in FIG. 2.

  Now, the drive pattern shown in FIG. 3 is referred to as pattern A, and the drive pattern shown in FIG. The drive pattern shown in FIG. 5 is referred to as pattern C, and the drive pattern shown in FIG. These patterns A to D are stored in advance in a memory (for example, the memory unit 307 shown in FIG. 1).

  In the patterns A to D, the timing (time T11, T11b, T11c, T11d) at which the transfer signal input pulse PTS becomes L level (low level) is different. Thus, the interval (time interval) between the timing when the transfer signal input pulse PTN becomes L level (T7) and the timing when the transfer signal input pulse PTS becomes L level is made different.

  As another example, although not shown, the timing at which the transfer signal input pulse PTN goes to L level is different for each drive pattern, and the timing at which the transfer signal input pulse PTN goes to L level and the transfer signal input pulse. The interval from the timing when the PTS becomes L level may be varied. That is, the difference from the timing when the transfer signal input pulses PTS and PTN become L level is important, and there is no problem even if the timing of pulses other than the transfer signal input pulses PTS and PTN varies depending on the drive pattern.

  Alternatively, although not shown, the length of the H level period (1H period) may be varied for each drive pattern. Furthermore, a plurality of drive patterns may be prepared by combining the above three types of pattern changing methods.

  In each drive pattern, the interval between the timing when the transfer signal input pulse PTN becomes L level and the timing when the transfer signal input pulse PTS becomes L level, or the length of the 1H period of each drive pattern is determined as follows. Is done.

  Among components incorporated in the imaging device, a DC / DC converter for performing voltage conversion of a power supply circuit of a flash unit and a DC / DC converter for performing voltage conversion of a power supply circuit of the imaging device are images. It shall be a noise source for the signal. Furthermore, a communication unit for communicating with an external device such as a motor for driving a lens barrel and a diaphragm of a lens and a PC among devices connected to the imaging apparatus is assumed to be a noise source of the image signal.

  At this time, based on the driving frequency of each noise source or the fluctuation frequency of the power supply when each noise source is electrically driven, the optical signal (S signal) and the noise signal (N signal) are held in the memory, The timing for determining each signal level is determined.

  FIG. 7 is a diagram for explaining an example of timing determination for determining the signal levels of the optical signal (S signal) and the noise signal (N signal).

  As shown in FIG. 7, the difference between the offsets related to the power supply of the solid-state imaging device 303 becomes zero between the timing when the transfer signal input pulse PTN becomes L level and the timing when the transfer signal input pulse PTS becomes L level. As described above, one or both of the timing when the transfer signal input pulse PTN becomes L level and the timing when the transfer signal input pulse PTS becomes L level is determined.

  FIG. 8 is a diagram for explaining another example of determination of timing for determining the signal levels of the optical signal (S signal) and the noise signal (N signal).

  As shown in FIG. 8, paying attention to the length of the 1H period for reading a predetermined row and the length of the 1H period for reading a row before and after the predetermined row, the timing at which the transfer signal input pulse PTN becomes L level And the timing at which the transfer signal input pulse PTS becomes the L level, the difference in offset relating to the power supply of the image sensor is made equal in each 1H period.

  For example, by adjusting the length of the 1H period of each pattern A to D (drive pattern), the timings at which the transfer signal input pulse PTN in each 1H period becomes L level and the timings at which the transfer signal input pulse PTS becomes L level Adjust the distance between each other. Thereby, the difference in offset can be made constant.

  Further, the magnitude of the influence of noise on each image source by the noise sources is ranked, and these rankings are associated with the drive pattern and stored in the memory of the imaging apparatus. For example, the closer the distance between each noise source and the power supply circuit of the power supplied to the solid-state image sensor 303 or the solid-state image sensor 303 itself, the greater the influence on the power source of the solid-state image sensor 303 and the greater the noise on the image signal. .

  Further, when the fluctuation pattern due to the noise source is not regular in the offset of the power supply supplied to the imaging apparatus, the noise often becomes random fine horizontal stripes and is not visually noticeable. On the other hand, when the offset of the power supply fluctuates periodically, the noise becomes a periodic horizontal stripe pattern, which is visually noticeable. Then, in consideration of factors such as the magnitude of noise and conspicuousness, the magnitude of the influence of each noise source on the image signal is ranked and stored in the memory.

  FIG. 9 is a diagram for explaining an example of the relationship between the drive patterns A to D for driving the solid-state imaging device 303 shown in FIG. 2 and various devices a to d that are noise sources.

  When the relationship between the noise source and the driving patterns A to D of the solid-state imaging device is stored in the memory as described above, for example, as illustrated in FIG. 9, the devices a, b, c, and d are When the device a is electrically driven, it is associated with the drive pattern A that minimizes (minimizes) noise when the device a is electrically driven, and noise when the device b is electrically driven. Is associated with the drive pattern B that minimizes. A drive pattern C that minimizes noise when the device c is electrically driven is associated, and a drive pattern D that minimizes noise when the device d is electrically driven is associated. It is done.

  Furthermore, as shown in FIG. 9, when one of the drive patterns A to D is used as a reference pattern, and each device a to d is operated (electrically driven) when the solid-state imaging device 303 is driven by this reference pattern. The noise periods A1 to D1 are obtained, and these noise periods A1 to D1 are stored in the memory in association with the drive patterns A to D.

  For example, a DC / DC circuit that performs voltage conversion, such as a power supply circuit of an image pickup apparatus, is arranged in the image pickup apparatus and often moves simultaneously with signal readout. The DC / DC circuit has a high frequency of influence on the power supplied to the solid-state image sensor 303. Therefore, in order to match the noise caused by the DC / DC circuit, the pattern D in which the timing of S transfer and N transfer that hardly generate noise is set as the reference pattern.

  Further, the solid-state imaging device 303 is shielded from light by the reading operation by the pattern D as the reference pattern while each of the devices a, b, and c serving as noise sources is electrically driven and operated independently. Then, a plurality of lines of image data are read out, or an image signal for one line is read out a plurality of times to obtain black data. At this time, in the black data, noise due to the influence of the device d does not appear, but noise due to the influence of the noise source operated at the time of black data acquisition appears.

  Then, using the black data during the operation of each device a to c (during electrical driving), the horizontal stripe noise periods A1, B1 and C1 by each device a to c are calculated and associated with each drive pattern. Store in memory. Here, the noise period D1 when driving the device d is D = 0.

  FIG. 10 is a diagram for explaining an example of a method for obtaining the horizontal stripe noise period described in relation to FIG. 9.

  As shown in FIG. 10, the black data is added and averaged for each row to determine the offset amount in each row. Then, the inflection point is extracted from the offset amount of each row, the period of the horizontal stripe noise is obtained from the interval between the peaks, and stored in the memory.

  The plurality of driving patterns determined as described above are selected according to the electrical driving state of the noise source when reading the image signal, and the offset due to the influence of the noise source may affect the image signal. Do not.

  In the case of an interchangeable lens imaging device, the drive frequency of a built-in motor may differ depending on the lens to be connected. In such a case, an optimum driving pattern for the solid-state imaging device is prepared in advance for each lens that may be connected. Then, an optimum driving pattern for the solid-state imaging device is selected in accordance with the lens connected to the imaging device.

  11A and 11B are flowcharts for explaining an example of drive pattern selection in the imaging apparatus shown in FIG.

  Referring to FIGS. 1, 11A, and 11B, when the power is turned on, overall control / calculation unit 312 is in a half-pressed state in which a shooting start switch (not shown) instructs the start of shooting preparation. It is determined whether or not (SW1 = ON) (step S1). If SW1 = off (OFF) (NO in step S1), overall control / calculation unit 312 stands by. If SW1 = ON (YES in step S1), overall control / calculation unit 312 acquires information (data) related to the device connected to the imaging apparatus (step S2).

  For example, the overall control / calculation unit 312 acquires information such as the type of interchangeable lens connected to the imaging apparatus, the presence / absence and type of an external strobe, and the presence / absence and type of a wireless unit. Here, it is assumed that the overall control / calculation unit 312 detects that the devices a to d, which are four types of noise sources, are included in the imaging apparatus or in the connected device. Furthermore, it is assumed that the device d is a DC / DC circuit in the imaging apparatus.

  The overall control / arithmetic unit 312 sets the drive pattern (control pattern) of the solid-state image sensor 303 to pattern D, and reads out the image data of a plurality of rows in a state where the solid-state image sensor 303 is shielded from light, or an image for one row. Data is read a plurality of times, and black data used for determining the drive pattern is acquired (step S3).

  Subsequently, the overall control / arithmetic unit 312 calculates the amount of horizontal stripe noise in the black data using the black data (step S4). For example, as described with reference to FIG. 10, the overall control / calculation unit 312 calculates the offset amount of each row by averaging the black data for each row. Then, the overall control / arithmetic unit 312 calculates a variation σ between the addition average values and sets it as a noise amount determination value.

  Next, the overall control / calculation unit 312 determines whether or not the amount of horizontal stripe noise in the black data is equal to or greater than a predetermined amount (predetermined value) according to the noise amount (determination value) (step S5). . If it is determined that the amount of horizontal stripe noise is equal to or greater than the predetermined amount (YES in step S5), overall control / calculation unit 312 obtains the period of horizontal stripe noise based on the above-described addition average value, and the frequency of the noise source Is estimated (step S6). For example, the overall control / calculation unit 312 extracts the inflection point from the offset amount of each row, and estimates the period of the horizontal stripe noise from the interval between the peaks.

  Note that if only the device connected to the imaging device is a noise source, there is no problem even if the processing of steps S3 to S6 is not performed. If there is a device that generates strong electromagnetic waves such as a radio tower, the electromagnetic waves generated from these devices can also be a noise source that fluctuates the power supply of the imaging device.

  Since it is difficult to store information such as the presence / absence of a device not connected to the imaging device and its noise frequency in the memory of the imaging device in advance, the determination result of the noise amount and the noise cycle by the device are obtained. This is used when selecting the drive pattern.

  Subsequently, the overall control / calculation unit 312 determines whether or not the shooting start switch is in a fully-pressed state (SW2 = ON) instructing to start shooting (step S7). If it is determined that the amount of horizontal stripe noise is less than a predetermined amount (less than a predetermined value) (NO in step S5), overall control / calculation unit 312 proceeds to the process in step S7.

  If SW2 = OFF (NO in step S7), overall control / calculation unit 312 determines whether or not SW1 is released (step S8). That is, the overall control / calculation unit 312 determines whether or not the shooting start switch is in a half-pressed state (SW1 = ON) instructing to start shooting preparation.

  If SW1 = ON is maintained (NO in step S8), the overall control / calculation unit 312 returns to the process in step S7 and determines whether SW2 = ON. On the other hand, if SW1 = OFF (YES in step S8), that is, if the ON state of SW1 is released, overall control / calculation unit 312 returns to the process of step S1 to determine whether SW1 is turned on. Determine whether or not.

  If SW2 = ON (YES in step S7), overall control / calculation unit 312 determines whether or not the imaging preparation operation of the imaging apparatus such as distance measurement and photometry has been completed (step S9). If the shooting preparation operation has not been completed (NO in step S9), overall control / calculation unit 312 stands by.

  When the photographing preparation operation is completed (YES in step S9), the overall control / calculation unit 312 indicates N = 0 indicating the first read line in a counter (not shown) that counts the number of read lines in one frame. Is set (step S10). Then, the overall control / arithmetic unit 312 controls the timing generation unit 313 to sequentially start exposure of each pixel of the solid-state imaging device 304 for each row (row unit) (step SS11).

  Next, the overall control / arithmetic unit 312 determines whether or not the device a that has the strongest influence on the power supply of the imaging apparatus is electrically driven (that is, the electrical drive status) (step S12). If it is determined that the device a is electrically driven (YES in step S12), the overall control / calculation unit 312 determines that the signal to be read is affected by the noise of the cycle A1 by the device a, and the A drive pattern related to the signal reading operation of the image sensor 303 is set to pattern A (step S13).

  On the other hand, if it is determined that the device a is not electrically driven (NO in step S12), the overall control / calculation unit 312 electrically drives the device b that has the second strongest influence on the power supply of the imaging device. It is determined whether it has been performed (step S14). If it is determined that the device b is electrically driven (YES in step S14), the overall control / calculation unit 312 determines that the signal to be read is affected by the noise of the cycle B1 by the device b, and the The drive pattern of the signal reading operation of the image sensor 303 is set to pattern B (step S15).

  If it is determined that the device b is not electrically driven (NO in step S14), the overall control / calculation unit 312 is electrically driven with the device c that has the third strongest influence on the power supply of the imaging device. It is determined whether or not (step S16). If it is determined that the device c is electrically driven (YES in step S16), the overall control / arithmetic unit 312 determines that the signal to be read is affected by the noise of the cycle C1 caused by the device c. The drive pattern of the signal reading operation of the image sensor 303 is set to pattern C (step S17).

  If it is determined that the device c is not electrically driven (NO in step S16), the overall control / calculation unit 312 refers to the determination result in step S5 described above (step S18). If the horizontal stripe noise is equal to or greater than the predetermined amount (YES in step S18), the overall control / calculation unit 312 determines that there is some noise source in addition to the connected device outside the imaging device. Reference is made to the period of the horizontal stripe noise obtained in step S6.

  The overall control / calculation unit 312 determines whether or not the noise cycle is substantially equal to the noise cycle of the device a (step S19). If it is determined that the noise cycle is substantially equal to the noise cycle of device a (YES in step S19), overall control / calculation unit 312 determines that the signal to be read is affected by the noise of cycle A1 by some noise source. . Then, the overall control / arithmetic unit 312 sets the driving pattern of the signal reading operation of the solid-state image sensor 303 to pattern A (step S20).

  If it is determined that the noise cycle is different from the noise cycle of the device a (NO in step S19), the overall control / calculation unit 312 determines whether or not the noise cycle is substantially equal to the noise cycle of the device b ( Step S21). If it is determined that the noise cycle is substantially equal to the noise cycle of device b (YES in step S21), overall control / calculation unit 312 determines that the signal to be read is affected by the noise of cycle B1 by some noise source. . Then, the overall control / arithmetic unit 312 sets the driving pattern of the signal reading operation of the solid-state imaging device 303 to the pattern B (step S22).

  If it is determined that the noise cycle is different from the noise cycle of the device b (NO in step S21), the overall control / calculation unit 312 determines whether the noise cycle is substantially equal to the noise cycle of the device c ( Step S23). If it is determined that the noise cycle is substantially equal to the noise cycle of device c (YES in step S23), overall control / calculation unit 312 determines that the signal to be read is affected by the noise of cycle C1 by some noise source. . Then, the overall control / arithmetic unit 312 sets the driving pattern of the signal reading operation of the solid-state image sensor 303 to the pattern C (step S24).

  If it is determined that the noise cycle is different from the noise cycle by the device c (NO in step S23), the overall control / calculation unit 312 causes the signals to be read to be in the cycles A1, B1, C1, and D1 by some noise source. It is determined that it is affected by noise with a different period from each other. Then, the overall control / arithmetic unit 312 randomly selects the driving pattern of the signal reading operation of the nth row from the pattern A, the pattern B, the pattern C, and the pattern D so that the horizontal stripe noise is not visually noticeable. Select and set (step S25).

  Subsequently, the overall control / arithmetic unit 312 determines whether or not the exposure for the nth row has been completed (step S26). If the exposure for the nth row is not completed (NO in step S26), overall control / calculation unit 312 waits until the exposure is completed. On the other hand, if the exposure for the n-th row has been completed (YES in step S26), overall control / calculation unit 312 controls timing generation unit 313, and the n-th row according to the drive pattern set in step S25 described above. The eye signal is read from the solid-state image sensor 303 (step S27).

  Subsequently, the overall control / arithmetic unit 312 determines whether or not the reading of a predetermined number of rows included in the reading area has been completed (n <predetermined number of rows: step S28). If n <predetermined number of rows (YES in step S28), overall control / arithmetic unit 312 advances the counter for counting the number of read rows of one frame by 1 (step S29), and returns to the processing of step S25. The read operation for the next row is performed.

  If the horizontal stripe noise is less than the predetermined amount in step S18 (NO in step S18), the overall control / calculation unit 312 determines that there is no noise source other than the connected device, and the solid-state imaging device. The drive pattern of the signal read operation 303 is set to pattern D.

  Subsequent to step S13 described above, the overall control / arithmetic unit 312 determines whether or not the exposure for the nth row has been completed (step S31). Note that following steps S15, S17, S20, S22, S24, and S30, the overall control / calculation unit 312 performs the process of step S31.

  If the exposure for the n-th row has not been completed (NO in step S31), overall control / calculation unit 312 waits until the exposure is completed. On the other hand, if the exposure for the n-th row has been completed (YES in step S31), overall control / calculation unit 312 controls timing generation unit 313 to solidify the signal for the n-th row according to the set drive pattern. Read from the image sensor 303 (step S32).

  Subsequently, the overall control / arithmetic unit 312 determines whether or not the reading of the predetermined number of rows included in the reading area has been completed (n <predetermined number of rows: step S33). If n <predetermined number of rows (YES in step S33), the overall control / arithmetic unit 312 advances the counter for counting the number of read rows of one frame by 1 (step S34), and returns to the processing of step S31. The read operation for the next row is performed.

  If n = predetermined number of rows (NO in step S33), the overall control / arithmetic unit 312 completes the reading of one frame (step S35), and returns to the processing of step S7 to determine whether SW2 = ON. Determine whether or not. In step S28, if n = the predetermined number of rows (NO in step S28), overall control / calculation unit 312 proceeds to the process in step S35.

  Note that the image data obtained by driving the solid-state imaging element 303 described above is considered to have a shading shape with a different reference signal for each selected drive pattern. In particular, it has been found from experimental results that the shading shape in the horizontal direction differs because the offset difference of the signal generated for each unit pixel column differs depending on the selected drive pattern. Such shading appears as left and right unevenness in the screen or as vertical streak noise in the captured image.

  FIG. 12 is a diagram illustrating an example of shading correction data for each drive pattern.

  In FIG. 12, in order to perform shading correction, a black image is acquired in advance by each drive pattern (patterns A to D) in a state where the solid-state imaging element 303 is shielded from light. Then, an addition average value of pixel signals is obtained for each pixel column from the black image by each drive pattern, and this addition average value is used as correction data.

  When correcting the image signal read out from the solid-state imaging device 303, correction is performed using correction data obtained by the same drive pattern as that used at the time of photographing among these correction data. Good.

  FIG. 13 is a diagram illustrating correction for each read row.

  As shown in FIG. 13, when reading is performed by randomly selecting a driving pattern for each row (each row), depending on the driving pattern (any one of patterns A to D) when reading each row. Thus, the correction data may be selected.

  FIG. 14 is a diagram illustrating an example of the arrangement of the imaging region and the light shielding region of the solid-state imaging device 303.

  When reading is performed by randomly selecting a drive pattern for each row, as shown in FIG. 14, a plurality of rows of light-shielding pixels (in a region including a region adjacent to the imaging region of the solid-state image sensor 303 in the vertical direction). That is, a light shielding pixel region) is arranged. Then, with respect to the light-shielding pixel region, the correction data may be acquired by performing reading with the same driving pattern as that for the above-described shooting, and the correction data may be used for correction.

  FIG. 15 is a diagram illustrating an example of selection of a driving pattern when reading is performed for a light-shielded pixel region.

  When reading is performed by selecting a drive pattern at random for each row, as shown in FIG. 15, the light-shielded pixel region is read with a different drive pattern for each row, or the drive pattern is changed for the light-shielded pixel region. The correction data is obtained by repeating the reading a plurality of times. Then, when the image signal is corrected, correction data may be selected according to the driving pattern when each row is read out.

  The correction data may be acquired in advance as a factory adjustment value before shipment and stored in the memory. Further, correction data may be acquired before or after shooting or at the time of shooting.

(Second Embodiment)
FIG. 16A and FIG. 16B are flowcharts for explaining an example of drive pattern selection in the imaging apparatus according to the second embodiment of the present invention.

  The configuration of the imaging device according to the second embodiment is the same as that of the imaging device shown in FIG. 1, and the configuration of the solid-state imaging device is the same as that of the solid-state imaging device shown in FIG.

  Referring to FIGS. 1, 2, 16A and 16B, the same steps as those shown in FIGS. 11A and 11B are denoted by the same reference numerals, and description thereof is omitted.

  In the imaging device according to the second embodiment, the type of the noise source connected to the imaging device and the electrical driving state of each noise source are determined every time each pixel row in one frame is read. Then, a noise source having a large influence on the image signal is prioritized among noise sources that are electrically driven when the image signal is read, and a drive pattern corresponding to the noise source is selected.

  As described with reference to FIG. 11A, in step S10, the overall control / arithmetic unit 312 sets n = 0 indicating the first read row to the counter that counts the number of read rows in one frame. In step S11, the overall control / calculation unit 312 sequentially starts exposure of each pixel row of the solid-state imaging device 303 for each row.

  Subsequently, the overall control / calculation unit 312 determines whether or not the exposure of the n-th row has been completed (step S112). If the exposure for the n-th row has not been completed (NO in step S112), overall control / calculation unit 312 waits until the exposure is completed.

  If it is determined that the exposure of the n-th row has been completed (YES in step S112), the overall control / calculation unit 312 determines whether the device a that has the strongest influence on the power supply of the imaging device is electrically driven. Determination is made (step S113). If it is determined that the device a is electrically driven (YES in step S113), the overall control / calculation unit 312 determines that the signal to be read is affected by the noise of the cycle A1 by the device a, and the A drive pattern related to the signal reading operation of the image sensor 303 is set to the pattern A (step S114).

  On the other hand, if it is determined that the device a is not electrically driven (NO in step S113), the overall control / calculation unit 312 electrically drives the device b that has the second strongest influence on the power supply of the imaging device. It is determined whether it has been performed (step S115). If it is determined that the device b is electrically driven (YES in step S115), the overall control / calculation unit 312 determines that the signal to be read is affected by the noise of the cycle B1 by the device b, and the solid state is determined. The drive pattern of the signal reading operation of the image sensor 303 is set to pattern B (step S116).

  If it is determined that the device b is not electrically driven (NO in step S115), the overall control / calculation unit 312 is electrically driven with the device c that has the third strongest influence on the power supply of the imaging device. It is determined whether or not (step S117). If it is determined that the device c is electrically driven (YES in step S117), the overall control / calculation unit 312 determines that the signal to be read is affected by the noise of the cycle C1 by the device c, and the The drive pattern of the signal reading operation of the image sensor 303 is set to pattern C (step S118).

  If it is determined that the device c is not electrically driven (NO in step S117), the overall control / calculation unit 312 refers to the determination result in step S5 described above (step S119). If the horizontal stripe noise is equal to or greater than the predetermined amount (YES in step S119), the overall control / calculation unit 312 determines that there is some noise source in addition to the connected device outside the imaging device. Reference is made to the period of the horizontal stripe noise obtained in step S6.

  The overall control / calculation unit 312 determines whether or not the noise cycle is substantially equal to the noise cycle of the device a (step S120). If it is determined that the noise cycle is substantially equal to the noise cycle of device a (YES in step S120), overall control / calculation unit 312 determines that the signal to be read is affected by the noise of cycle A1 by some noise source. . Then, the overall control / arithmetic unit 312 sets the driving pattern of the signal reading operation of the solid-state image sensor 303 to pattern A (step S21).

  If it is determined that the noise cycle is different from the noise cycle of the device a (NO in step S120), the overall control / calculation unit 312 determines whether the noise cycle is substantially equal to the noise cycle of the device b ( Step S122). If it is determined that the noise cycle is substantially equal to the noise cycle of device b (YES in step S122), overall control / calculation unit 312 determines that the signal to be read is affected by the noise of cycle B1 by some noise source. . Then, the overall control / arithmetic unit 312 sets the driving pattern of the signal reading operation of the solid-state imaging device 303 to the pattern B (step S123).

  If it is determined that the noise cycle is different from the noise cycle of the device b (NO in step S122), the overall control / calculation unit 312 determines whether the noise cycle is substantially equal to the noise cycle of the device c ( Step S124). If it is determined that the noise cycle is substantially equal to the noise cycle of device c (YES in step S124), overall control / calculation unit 312 determines that the signal to be read is affected by the noise of cycle C1 by some noise source. . Then, the overall control / arithmetic unit 312 sets the driving pattern of the signal reading operation of the solid-state imaging device 303 to the pattern C (step S125).

  If it is determined that the noise cycle is different from the noise cycle by the device c (NO in step S124), the overall control / calculation unit 312 causes the signal to be read to be in the cycles A1, B1, C1, and D1 depending on some noise source. It is determined that it is affected by noise with a different period from each other. Then, the overall control / arithmetic unit 312 randomly selects the driving pattern of the signal reading operation of the nth row from the pattern A, the pattern B, the pattern C, and the pattern D so that the horizontal stripe noise is not visually noticeable. Select and set (step S2126).

  If the horizontal stripe noise is less than the predetermined amount in step S119 (NO in step S119), the overall control / calculation unit 312 determines that there is no noise source other than the connected device, and the solid-state imaging device. The drive pattern of the signal read operation 303 is set to pattern D (step S127).

  Subsequent to step S114 described above, the overall control / arithmetic unit 312 controls the timing generation unit 313 to read the n-th row signal from the solid-state imaging device 303 according to the set drive pattern (step S128). Note that, following steps S116, S118, S121, S123, S125, S126, and S127, the overall control / calculation unit 312 performs the process of step S128.

  Subsequently, the overall control / arithmetic unit 312 determines whether or not the reading of the predetermined number of rows included in the reading area has been completed (n <predetermined number of rows: step S129). If n <predetermined number of rows (YES in step S129), overall control / arithmetic unit 312 advances the counter for counting the number of rows read in one frame by 1 (step S130), and returns to the processing in step S112. It is determined whether or not the exposure for the next row is completed.

  If n = the predetermined number of rows (NO in step S129), the overall control / arithmetic unit 312 completes the reading of one frame (step S131), and returns to the processing in step S7 to determine whether SW2 = ON. Determine whether or not.

  Note that, also in the imaging apparatus according to the second embodiment, as described with reference to FIGS. 12 to 15, correction data is generated and an image signal read from the solid-state imaging element 303 is corrected with the correction data.

  As described above, according to the embodiment of the present invention, it is possible to reduce the superposition of noise components such as horizontal stripes on the image signal due to the noise source, and to maintain good image quality.

  As is clear from the above description, in FIGS. 1 and 2, the vertical scanning circuit 411 and the horizontal scanning circuit 421 function as reading means. The overall control / calculation unit 312 functions as a control unit. The overall control / arithmetic unit 312 also functions as a first determination unit and a second determination unit. The overall control / arithmetic unit 312 adjusts the readout time interval for each row in the selected drive pattern in accordance with the noise frequency from the noise source, so that the noise signal in each row is in phase.

  As mentioned above, although this invention was demonstrated based on embodiment, this invention is not limited to these embodiment, Various forms of the range which does not deviate from the summary of this invention are also contained in this invention. .

  For example, the function of the above embodiment may be used as a control method, and this control method may be executed by imaging. In addition, a control program having the functions of the above-described embodiments may be executed by a computer included in the imaging apparatus.

  The control program is recorded on a computer-readable recording medium, for example.

  The present invention is also realized by executing the following processing. That is, software (program) that realizes the functions of the above-described embodiments is supplied to a system or apparatus via a network or various storage media, and a computer (or CPU, MPU, etc.) of the system or apparatus reads the program code. It is a process to be executed. In this case, the program and the storage medium storing the program constitute the present invention.

303 Solid-state imaging device 304 Imaging signal processing circuit 306 Signal processing unit 312 Overall control / calculation unit 313 Timing generation unit 315 Power supply circuit 400 Unit pixel 411 Vertical scanning circuit (VSR)
421 Horizontal scanning circuit (HSR)
431 Differential circuit block 431

Claims (12)

A plurality of unit pixels arranged in a two-dimensional matrix, a reading means for reading out an optical signal and a noise signal from the unit pixel in a row unit, and a differential signal output for outputting a difference between the optical signal and the noise signal as an image signal An imaging device comprising means;
Memory means for storing a plurality of drive patterns having different readout timings of at least one of the optical signal and the noise signal by the readout means;
It is determined whether or not a noise source that fluctuates a power supply voltage of the image pickup device is electrically driven, and when it is determined that the noise source is electrically driven, the noise source from the memory means An image pickup apparatus comprising: a control unit that selects a drive pattern corresponding to 1 and performs read-out control of the image pickup device with the selected drive pattern.   The control means adjusts a readout time interval for each row in the selected drive pattern according to a noise frequency from the noise source, and makes a noise signal in each row in phase. The imaging device described in 1.   The control means adjusts the readout timing of the optical signal and the readout timing of the noise signal in the selected drive pattern in accordance with the noise frequency from the noise source to cancel the noise of the noise source. The imaging apparatus according to claim 1, wherein the imaging apparatus is characterized.   The image pickup apparatus according to claim 1, wherein the control unit selects a drive pattern from the memory unit according to a noise source that most influences the image signal.   The said control means selects a drive pattern from the said memory means for every reading of 1 line according to the electrical drive condition of the said noise source, The any one of Claims 1-3 characterized by the above-mentioned. Imaging device.   The image pickup apparatus according to claim 1, wherein the noise source is at least one of a component inside the image pickup apparatus and a device connected to the image pickup apparatus.   One of the drive patterns is stored as a reference pattern in the memory means, and the control means is configured to reduce noise superimposed on a noise signal obtained when performing readout control of the image sensor with the reference pattern. 7. The image signal is obtained by selecting a drive pattern according to a cycle and performing read-out control of the image sensor with the selected drive pattern. 8. The imaging device described.   The imaging apparatus according to claim 7, wherein the reference pattern is a drive pattern corresponding to a noise source that frequently generates noise. First determination means for determining whether or not a noise source other than the noise source corresponding to the reference pattern is electrically driven;
If it is determined by the first determination means that the noise sources other than the noise source corresponding to the reference pattern are not electrically driven, the noise in the black data obtained by the read control by the reference pattern is predetermined. Second determining means for determining whether or not the value is greater than or equal to the value,
The control unit selects the drive pattern according to the period of the noise when the second determination unit determines that the noise in the black data is equal to or greater than a predetermined value. Or the imaging device of 8.   10. The control unit according to claim 9, wherein when the noise in the black data is determined to be less than a predetermined value by the second determination unit, the control unit performs readout control of the image sensor based on the reference pattern. Imaging device. A plurality of unit pixels arranged in a two-dimensional matrix, a reading means for reading out an optical signal and a noise signal from the unit pixel in a row unit, and a differential signal output for outputting a difference between the optical signal and the noise signal as an image signal For controlling an image pickup apparatus comprising: an image pickup device including a plurality of drive patterns; and a memory unit that stores a plurality of drive patterns having different read timings of at least one of the optical signal and the noise signal by the read out unit. A control method,
A determination step of determining whether or not a noise source that fluctuates a power supply voltage of the image sensor is electrically driven;
A selection step of selecting a drive pattern corresponding to the noise source from the memory means when it is determined in the determination step that the noise source is electrically driven;
A control step of performing readout control of the image sensor with the drive pattern selected in the selection step. A plurality of unit pixels arranged in a two-dimensional matrix, a reading means for reading out an optical signal and a noise signal from the unit pixel in a row unit, and a differential signal output for outputting a difference between the optical signal and the noise signal as an image signal For controlling an image pickup apparatus comprising: an image pickup device including a plurality of drive patterns; and a memory unit that stores a plurality of drive patterns having different read timings of at least one of the optical signal and the noise signal by the read out unit. A control program,
In the computer provided in the imaging device,
A determination step of determining whether or not a noise source that fluctuates a power supply voltage of the image sensor is electrically driven;
A selection step of selecting a drive pattern corresponding to the noise source from the memory means when it is determined in the determination step that the noise source is electrically driven;
And a control step of performing a read control of the image sensor with the drive pattern selected in the selection step.