JP3866699B2 - Imaging device driving method, imaging device using the method, imaging monitor device, and observation system - Google Patents

Description

  The present invention relates to an imaging element driving method, an imaging apparatus using the method, an imaging monitor apparatus, and an observation system, and in particular, a TDI (time delay integration) type CCD (charge coupled device) driving method, The present invention relates to an imaging apparatus, an imaging monitor apparatus, and an observation system using the method.

  FIG. 10 shows a configuration diagram of an example of a one-dimensional CCD. The CCD image sensor 10 accumulates signal charges generated by the amount of light received by the photosensor 1 in the separated potential well and outputs from the horizontal transfer unit (analog shift register) 2 so that the accumulated charges are not mixed. It is transferred to the unit 3 and output as an electrical signal.

  A TDI type CCD to which a TDI function that can secure a sufficiently large signal level by integration of signal components is used for imaging a moving object with minute light and imaging from a moving imaging apparatus.

  The TDI function is a method in which a sufficiently large charge can be obtained by performing charge movement in the CCD vertical direction in synchronization with the movement of the image pickup object or the image pickup apparatus and integrating the charge normally obtained at a magnification proportional to the number of TDI stages.

  An example of the TDI operation is shown in FIG. As an example, a case where a donut-shaped object to be imaged 4 is imaged by a moving imaging device using the TDI type CCD 10 will be described. In FIG. 11, it is assumed that the number of TDI stages is four as an example, and the imaging device 4 moves upward while the imaging target 4 is stationary.

  (1) FIG. 12 is a diagram showing an example of the flow of TDI operation. As shown in the figure, the object to be imaged 4 appears on the image pickup apparatus, and the image 4 moves on the CCD 10 in the direction opposite to the movement direction of the image pickup apparatus, that is, downward, by the movement of the image pickup apparatus.

  (2) As shown in FIG. 12A, when the object to be imaged 4 appears on the CCD 10, the corresponding pixel in the first stage in the moving direction has a charge proportional to the energy of the object to be imaged 4. In this embodiment, the charge is indicated by a black dot. FIG. 12A shows that two charges are accumulated in the pixel 5a as an example.

  (3) As shown in FIG. 12B, when the object to be imaged 4 moves on the CCD 10 by one line, the entire generated charge due to the image 4 reflected in the CCD 10 is simultaneously moved downward by one line. This operation is called a TDI operation, and the charge accumulated in the first stage pixel is the same part of the imaged object 4 in which the second stage pixel is imaged in the first stage with a time delay due to the movement of the imaging device. Is added to the electric charge generated by the reflected image, resulting in a double electric charge amount (2 to 4 black dots indicating electric charge). That is, while the charge of the pixel 5a in FIG. 12A is two, the charge of the pixel 5b in FIG. 12B is a total of four charges when the two charges of the pixel 5a are added.

  (4) The eight scenes shown in FIGS. 12A to 12H show this operation for each target position. That is, the charge of the pixel 5c in FIG. 12C is a total of six charges by adding four charges of the pixel 5b, and the charge of the pixel 5d in FIG. 12D is a sum of adding six charges of the pixel 5c. Eight. Hereinafter, in FIG. 12E to FIG. 12H as well, the pixel charge is added as the imaging apparatus moves. Similarly, charges are added to the other pixels as the imaging apparatus moves.

  With this operation (TDI operation), the position of the electric charge obtained from the object to be imaged 4 always exists at the same symmetrical position even when the imaging apparatus moves.

  (5) As described above, in proportion to the number of stages in the vertical direction, a charge amount obtained by adding the charges obtained in each pixel is added, and the sensitivity increases as the signal level increases.

  (6) The electric charge increased in the TDI section is output as an electrical signal to the outside through the analog shift register 2 for reading at the bottom stage of the CCD and the output section 3.

  (7) FIG. 13 shows an enlarged view of an image of the donut-shaped object 4 imaged by the imaging device. Reference numerals 2c to 2h shown on the left side of FIG. 13 correspond to the analog shift registers 2c to 2h of FIG. That is, the first stage data of the CCD indicated by 2c in FIG. 13 is stored in the shift register 2c in FIG. 12C, and the second stage data of the CCD indicated by 2d in FIG. 13 is shifted in FIG. Similarly, it is shown until the sixth stage data of the CCD indicated by 2h in FIG. 13 is stored in the shift register 2h in FIG. 12 (h).

  Conventionally, the vertical transfer driving for the TDI operation of the TDI type CCD described above performs vertical transfer by the vertical three-phase transfer clocks Ck1Va, Ck2Va, Ck3Va as in the vertical transfer method shown in the timing chart of FIG. Concentrated during the horizontal transfer suspension period.

  In the vertical transfer, by changing the level of the Ck3Va electrode from “L” (low level) to “H” (high level), the charge accumulated in the Ck1Va electrode moves to the Ck3Va electrode, and then the level of the Ck2Va electrode is changed. By changing from “L” to “H”, the charge accumulated in the Ck3Va electrode moves to the Ck2Va electrode, and the accumulated charge moves one stage to the next stage.

  FIG. 15 shows the energy collection area of each pixel in the TDI driving method according to the conventional method. A square (b) in the center of FIG. 15 indicates a TDI CCD pixel (right angle direction 2 × movement direction 6), and the movement direction of the imaging device is indicated by an arrow. The charge transfer in this case is shown in the right cell (c).

  After the imaging device has moved one line, the charge stored in the CCD is transferred upward by one line. Since light energy is accumulated in the pixels during the period in which the imaging apparatus moves by one line, different imaging targets are also imaged as the imaging apparatus moves.

  FIG. 15A on the left side shows the ratio of energy accumulated in the corresponding pixel with respect to each position of the object to be imaged in the moving direction and in the horizontal direction.

  From the figure (a) showing the stored energy on the left side of FIG.

  (1) The energy accumulated in each pixel extends over an area for two lines.

  (2) When two lines of energy are mixed, the image is blurred (the MTF is reduced).

  As an example of this type of TDI CCD, the signal charge of the defective pixel among the pixels of the plurality of light receiving element rows may be transferred to the storage unit row by a switch row that opens and closes for each pixel based on the defective pixel information. An image sensor that can prevent the S / N ratio from decreasing due to defective pixels is disclosed (see Patent Document 1).

JP-A-6-90407 (paragraph 0011, FIG. 1)

  For imaging with minute light, a TDI type CCD is used to secure a stable signal level. However, as described above, the energy accumulated in each pixel spreads over an area corresponding to two lines by moving the imaged object or picking up an image from the moving image pickup apparatus. For this reason, the acquired image is blurred and a problem that a clear image cannot be acquired occurs.

  The reason is that the TDI vertical charge transfer is performed during the period when the CCD horizontal shift register is stopped for each horizontal scanning unit, so that the information acquisition range is widened and energy for two lines in the moving direction is accumulated in each pixel. Because. For this reason, the image in the moving direction of the acquired image is blurred (the MTF is reduced).

  In order to solve this problem, the present invention does not concentrate the vertical transfer during the period when the CCD horizontal shift register is stopped every horizontal scanning unit, and the CCD horizontal shift register is in operation. Including the vertical transfer in multiple times.

  However, in this case, since vertical transfer is performed during the horizontal register operation, there is a problem that noise due to the vertical transfer clock may be added to the CCD output signal.

  In this case, unlike the level of the other parts, the vertical line due to the noise is generated in the image where the noise of the captured image is placed.

  FIG. 16 shows an example of a waveform in which noise due to the vertical transfer clock is added to the CCD output signal. The waveform of the portion indicated by the arrow in the figure shows the noise given to the CCD output signal when the vertical transfer clock changes from “H” to “L”.

  This is because the influence of the change in the internal potential of the CCD due to the steep ON / OFF of the vertical transfer clock during the CCD horizontal transfer appears as noise in the CCD output.

  Therefore, an object of the present invention is to use an TDI type CCD to capture an image blur in the moving direction of an acquired image when a moving imaged object is imaged or when a stationary imaged object is imaged from an image pickup apparatus. There is to improve. Another object is to prevent noise generated by the vertical transfer clock in the signal output even if vertical transfer is performed a plurality of times during horizontal transfer.

In order to solve the above problems, an image sensor driving method according to the present invention includes a plurality of light receiving pixels arranged on a light receiving surface and generating a pixel output according to the amount of received light, and optical scanning of a light image on the light receiving surface. At the same timing, the pixel output of the light receiving pixel is vertically transferred, and is added to one of the output ends of the vertical transfer unit and a vertical transfer unit that adds pixel outputs sequentially generated along the optical scanning path. An image sensor driving method in an imaging device including a horizontal transfer unit that horizontally transfers a pixel output from the vertical transfer unit, wherein the method divides the vertical transfer of the pixel output into a fixed period including a horizontal transfer period. a vertical transfer control step of performing a plurality of times, falling or a period of time after the rising edge of the vertical transfer clock or a period of time before and after the falling or rising, the horizontal transfer clock one o'clock Te Characterized in that it comprises a horizontal transfer clock control step that locked.
In addition, an imaging device according to the present invention includes a plurality of light receiving pixels arranged on a light receiving surface and generating a pixel output according to the amount of received light, and the light receiving pixels in synchronization with an optical scanning of an optical image on the light receiving surface. The pixel output from the vertical transfer unit is arranged at one of the vertical transfer unit that vertically transfers the pixel output of the pixel and adds the pixel outputs sequentially generated along the optical scanning path, and the output end of the vertical transfer unit. An image pickup apparatus including a horizontal transfer unit for horizontally transferring an output, wherein the apparatus divides vertical transfer of the pixel output into a predetermined period including a horizontal transfer period and performs a plurality of times, and a vertical transfer clock to the falling or a period of time after the rising edge or a certain period before and after the falling or rising, characterized in that it comprises a horizontal transfer clock control means for stopping the horizontal transfer clock one o'clock .
According to the present invention, the vertical transfer of the pixel output is divided into a predetermined period including the horizontal transfer period and performed a plurality of times, so that it is possible to improve the image blur in the moving direction of the acquired image.

  According to the present invention, since it includes the above-described configuration, it is possible to improve image blurring in the moving direction of an acquired image when a moving imaged object is imaged or when a stationary imaged object is imaged from a moving imaging device. In addition, even if vertical transfer is performed a plurality of times during horizontal transfer, it is possible to prevent noise from being generated due to the vertical transfer clock in the signal output.

  FIG. 1 is a schematic explanatory view showing an example of the operation of the image sensor driving method according to the present invention. Hereinafter, the TDI operation by the vertical two-phase driving of the present invention will be described in comparison with the conventional driving method of FIG.

  (1) In the prior art, the CCD accumulated charge is transferred upward after the image pickup apparatus moves by one line. On the other hand, in the present invention, as shown in the right side (c) and (d) of FIG. 1, charge transfer is shown in comparison with the prior art. The charge is moved 1/2 to the next stage, and when the image pickup device has moved 1/2 line, the CCD accumulated charge is moved to the next stage, and the accumulated charge is transferred twice during the period of 1 line movement. Transfer to the next stage.

  By this driving method, an area that captures an object having a different moving direction is narrowed, and mixing with the generated charge in the adjacent area is reduced. Similarly, the left side (a) of FIG. 1 shows the energy collection area of each pixel.

  As described above, in the TDI operation, by blurring the transfer charge in the moving direction, the blur of the acquired image due to imaging from the imaging target or the moving imaging device can be reduced, and a clear image can be acquired.

  If the number of transfers of the accumulated charge to the next stage by the TDI operation in one line movement period is α, the MTF from the object to be imaged or the moving imaging device is expressed by the following equation, and the MTF increases as the number of transfers α increases. .

  MTF = sin (π / 2α) / (π / 2α)

  (2) In the present invention, noise generated due to a change in the vertical clock is stopped in the vertical transfer clock after the vertical transfer clock change (rising or falling), or before or after the vertical transfer clock, or when the vertical transfer clock has a sharp rise or fall. The problem can be solved by mitigating the downlink or by combining the above two methods.

  Next, the operation of the present invention will be described.

  (1) FIG. 2 is a timing chart showing an example of the operation of the vertical transfer method of the present invention. This figure shows the case of a three-phase clock as an example of the vertical transfer method. Referring to the figure, according to the present invention, the vertical transfer of accumulated charges is not concentrated in a short period of time when horizontal transfer is stopped, but one period of horizontal transfer is equally divided into three to perform vertical transfer.

  With this driving method, the accumulated charge can be transferred to the next stage for every 1/3 line movement, the area that captures the object with different movement direction becomes narrow, the mixture with the generated charge in the adjacent area decreases, and the MTF decreases. Can be improved.

  (2) Although the MTF reduction can be improved by the driving method shown in (1) above, noise may be generated by performing vertical transfer during horizontal transfer. In the present invention, as a solution when noise occurs, a method of temporarily stopping the horizontal clock after the rising edge of the vertical transfer clock, or a period before and after, or a method of reducing the steep rising and falling edges of the vertical transfer clock Alternatively, the generation of noise due to a change in the vertical clock can be solved by a method combining the above solutions.

  FIG. 3 is a timing chart showing the relationship among the vertical transfer clock, horizontal transfer clock and CCD output in the present invention. Referring to the figure, vertical transfer is performed by vertical transfer clock Ck1V, and horizontal transfer is performed by two-phase horizontal transfer clocks Ck1H and Ck2H. As shown in FIG. 3A, the CCD output is affected by a steep change in the rise and fall of the vertical transfer clock Ck1V, and noise is generated.

  On the other hand, in the present invention, as shown in FIG. 3B, the vertical transfer clock Ck1V rises and rises, rises and rises when the vertical transfer clock Ck1V rises and rises for a certain period in which the CCD output after the sharp change is affected. The horizontal transfer clocks Ck1H and Ck2H are stopped for a certain period before and after the steep downward change, and the horizontal transfer clocks Ck1H and Ck2H are restarted after a lapse of time not affected by the vertical transfer clock.

  Alternatively, as shown in FIG. 3 (C), the horizontal transfer clocks Ck1H and Ck2H are not stopped for a certain period by relaxing steep changes in the rise and fall of the vertical transfer clock Ck1V so as not to affect the CCD output. We are trying to solve the problem.

  Furthermore, the problem can be solved by combining the above two methods.

  FIG. 4 is a configuration diagram of a first embodiment of an imaging apparatus using the driving method according to the present invention. The figure shows a basic TDI type using a driving method in which vertical transfer is equally divided in time during a horizontal transfer period, which improves blurring of an acquired image due to a decrease in MTF in the moving direction due to movement of an object to be imaged or an imaging device. 2 shows an example of a functional block of a CCD image sensor (imaging camera).

  As shown in the figure, the TDI type CCD image sensor includes an optical unit 11 including a lens that forms an image of an object to be picked up on the light receiving surface of the TDI type CCD 12, and an image pickup target imaged on the light receiving surface. TDI type CCD 12 having a function of converting a received light amount change due to an object into an electric signal, a bias voltage generating unit 13 for generating a bias voltage necessary for the TDI type CCD 12, and a signal such as photoelectrically converted signal amplification of the TDI type CCD 12 A signal processing circuit unit 14 for processing, a CCD drive signal generation circuit unit 15 for generating a drive clock such as vertical transfer and horizontal transfer necessary for driving the TDI type CCD 12, and conversion to a necessary voltage from an external power supply input The power supply unit 16 is supplied to each unit.

  An image of the object to be imaged is formed on the light receiving surface of the TDI type CCD 12 by the optical unit 11. The change in the amount of received light imaged by the TDI type CCD 12 is photoelectrically converted into an electric signal and sent to the signal processing circuit unit 14. The signal processing circuit unit 14 performs signal processing such as amplification on the image pickup signal of the TDI type CCD 12 subjected to photoelectric conversion, and outputs it to an external device as an image sensor output.

  The CCD drive signal generator 15 generates a three-phase vertical transfer clock signal that equally divides the horizontal one-line transfer period of the present invention shown in FIG. 2 for driving the TDI type CCD 12 and supplies it to the TDI type CCD 12. ing.

  By driving the TDI type CCD 12 with the three-phase vertical transfer clock of the driving method according to the present invention, the object to be imaged or the image sensor generated by the driving method of performing vertical transfer in a short time concentrated on the conventional horizontal transfer stop period MTF reduction caused by movement can be improved, and an improved image blur signal with improved MTF can be obtained.

  When the charges generated on the light receiving surface of the TDI CCD 12 are vertically transferred by the vertical transfer clock during the horizontal transfer operation, noise may be generated in the output of the TDI CCD 12.

  FIG. 5 is a block diagram of a second embodiment of the imaging apparatus using the driving method according to the present invention. This figure shows the TDI CCD image sensor function of the driving method of the present invention, which has solved the problem of noise generated in the TDI CCD 12 output due to vertical transfer during the horizontal transfer period.

  FIG. 5 shows an embodiment in which a function for temporarily stopping the horizontal clock is provided during a period affected by steep rise and fall so as not to be affected by the vertical transfer clock.

  The basic functions are the same as those in FIG. 4, and the same components as those in FIG. In this embodiment, driving of the TDI type CCD 12 will be described.

  The drive clock from the CCD drive signal generator 15 is supplied to the TDI CCD 12 via the horizontal transfer clock temporary stop circuit 17 and drives the TDI CCD 12 by the method of the present invention.

  The horizontal transfer clock temporary stop circuit 17 is constituted by a delay timer or the like, operates at the rising or falling edge of the vertical transfer clock, and transfers the horizontal transfer clocks Ck1H and Ck2H to the TDI CCD 12 from the CCD drive signal generator 15 for a set period. Is stopped as if the horizontal clock shown in FIG.

  With this function, the signal of the TDI CCD 12 that is not affected by the vertical transfer clock can be acquired.

  FIG. 6 is a configuration diagram of a third embodiment of the imaging apparatus using the driving method according to the present invention. This figure shows another example of the TDI CCD image sensor function of the driving method of the present invention, which solves the problem that noise is generated in the output of the TDI CCD 12 due to vertical transfer during the horizontal transfer period.

  In the third embodiment, as shown in FIG. 3C, the influence of steep rise and fall of the vertical clock is removed by relaxing the rise or fall time.

  In FIG. 6, the clock for driving the TDI type CCD 12 from the CCD drive signal generation circuit 15 is supplied to the vertical clock rise / fall time relaxation circuit 18. The vertical clock rise / fall time relaxation circuit 18 is composed of a time constant circuit such as a capacitor so that the steep rise and fall times of the vertical transfer clock have no problem in driving the TDI CCD 12 and no noise is generated. It is relaxed and supplied to the TDI type CCD 12.

  The output of the TDI CCD 12 that is not affected by the vertical transfer clock as shown in FIG. 3C can be acquired by the function of the vertical clock rising / falling mitigation circuit 18.

  As in the above-described embodiments, the driving method of the present invention can improve the decrease in MTF caused by the movement of the object to be imaged or the movement of the image sensor with the same configuration and shape as before, and the image blur with improved MTF can be improved. A clear image signal can be acquired.

  FIG. 7 is a configuration diagram of an example of an imaging monitor device when the imaging device according to the present invention is used as an image sensor in the imaging monitor device.

Referring to the figure, the photographing monitor device includes an image sensor 21, a signal processing unit 22, and a monitor unit 23. The image sensor 21 images the moving object to be imaged 4.

  An output signal from the image sensor 21 of the imaged object 4 is transmitted to the signal processing device 22, and a plurality of one-dimensional signals from the image sensor 21 are accumulated and converted into a two-dimensional display signal.

  The converted two-dimensional signal is displayed on a monitor unit 23 including a display such as a CRT (cathode-ray tube) installed in a monitoring room at a remote location.

With the image sensor of the driving method of the present invention, an image with improved blur in the moving direction can be obtained,
It is possible to monitor the state of the moving image pickup object, which is difficult to identify with the conventional method.

  FIG. 8 is a block diagram of an example of an earth observation system using a satellite using the image sensor according to the present invention. In this system, the image sensor according to the present invention is mounted on a satellite.

  Referring to the figure, the earth observation system includes a satellite 31 and a ground station 32, and the ground station 32 includes a receiving unit 41, a signal processing unit 42, a display unit 43, and a control unit 44. Reference numeral 51 denotes the earth, and 52 denotes an imaging region.

  An observation image of the earth 51 is picked up by the image pickup device configured by the image sensor 21 of the TDI type CCD drive system of the present invention mounted on the satellite 31. The area to be imaged has a band shape as the satellite moves as the area indicated by the area 52 to be imaged.

  In the conventional TDI type CCD driving system, the MTF decreases with the progress of the satellite and becomes a blurred image in the conventional TDI type CCD driving system, but an image with improved blur can be acquired by the TDI type CCD driving system of the present invention.

  The captured observation image is transmitted to the ground station 32, and as shown in the ground station processing block diagram, the observation image received by the receiving unit 41 is subjected to signal processing such as image processing by the signal processing unit 42, and the display unit 43 is displayed on the monitor.

  Further, the observation signal processed by the signal processing unit 42 is controlled by the control unit 44 such as recording and storage and transmission to the outside.

  FIG. 9 is a diagram showing a comparison of MTF theoretical values between the TDI type CCD driving method according to the present invention and the conventional TDI type CCD driving method.

  As an example, the method of the present invention shows a case where TDI vertical transfer is performed by time division into three phases, and the conventional method shows a case where TDI vertical transfer is concentrated in a horizontal transfer register stop period.

  As can be seen from the figure, the TDI type CCD driving method according to the present invention has an MTF of about 1.5 times that of the conventional method.

  The reason is that the vertical transfer is divided into a plurality of parts including the period during which the horizontal transfer is operating.

  Even if vertical transfer is performed during the horizontal transfer period, the influence (noise) of the vertical transfer clock on the CCD output signal can be removed.

  The reason is that the horizontal transfer clock is stopped for a certain period after the rising or falling of the vertical transfer clock that gives noise to the CCD output signal, or for a certain period before and after that, and the vertical transfer clock is “H” or “L”. This is because the horizontal transfer clock is re-driven after being fixed at the level. Alternatively, the steep rise and fall times of the vertical transfer clock are relaxed so as not to affect the CCD output signal as noise.

It is a schematic explanatory drawing which shows an example of operation | movement of the image pick-up element drive method which concerns on this invention. It is a timing chart which shows an example of operation | movement of the vertical transfer method of this invention. 3 is a timing chart showing the relationship between a vertical transfer clock, a horizontal transfer clock, and a CCD output in the present invention. It is a block diagram of 1st Example of the imaging device using the drive method by this invention. It is a block diagram of 2nd Example of the imaging device using the drive method by this invention. It is a block diagram of 3rd Example of the imaging device using the drive method by this invention. It is a block diagram of an example of an imaging monitor apparatus when the imaging apparatus according to the present invention is used as an image sensor in an imaging monitor apparatus. It is a block diagram of an example of the earth observation system by the satellite using the image sensor which concerns on this invention. It is a figure which shows the comparison of the MTF theoretical value of the TDI type | mold CCD drive method by this invention, and the TDI type | mold CCD drive method by the conventional method. It is a block diagram of an example of a one-dimensional CCD. It is a figure which shows an example of TDI operation | movement. It is a figure which shows an example of the flow of TDI operation | movement. It is an enlarged view of the image of the to-be-photographed object 4 imaged with the imaging device. It is a timing chart of an example of the conventional vertical transfer method. It is a schematic explanatory drawing which shows an example of operation | movement of the conventional image pick-up element drive method. It is a figure which shows the noise by a vertical transfer clock.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Photosensor 2 Horizontal transfer part 3 Output part 4 Object to be picked 10 TDI type CCD
11 Optics 12 TDI CCD
DESCRIPTION OF SYMBOLS 13 Bias voltage generation part 14 Signal processing circuit part 15 CCD drive signal generation circuit part 16 Power supply part 17 Horizontal transfer clock temporary stop circuit 18 Vertical clock rise / fall time relaxation circuit 21 Image sensor 22 Signal processing part 23 Monitor part 31 Satellite 32 Ground station 41 Receiving unit 42 Signal processing unit 43 Display unit 44 Control unit

Claims (4)

A plurality of light receiving pixels arranged on the light receiving surface and generating a pixel output according to the amount of received light, and vertically transferring the pixel output of the light receiving pixel in time with the optical scanning of the optical image on the light receiving surface, A vertical transfer unit that adds pixel outputs sequentially generated along the path of optical scanning, and a horizontal transfer unit that is arranged at one of the output ends of the vertical transfer unit and horizontally transfers the pixel output from the vertical transfer unit; An imaging element driving method in an imaging apparatus including:
A vertical transfer control step in which the vertical transfer of the pixel output is divided into a predetermined period including a horizontal transfer period and performed a plurality of times ;
And a horizontal transfer clock control step of temporarily stopping the horizontal transfer clock for a certain period after the falling or rising of the vertical transfer clock, or for a certain period before and after the falling or rising . 2. The image pickup device driving method according to claim 1, further comprising a vertical transfer clock control step for alleviating steep rising and falling edges of the vertical transfer clock. A plurality of light receiving pixels arranged on the light receiving surface and generating a pixel output according to the amount of received light, and vertically transferring the pixel output of the light receiving pixels in time with the optical scanning of the optical image on the light receiving surface, A vertical transfer unit that adds pixel outputs sequentially generated along an optical scanning path; and a horizontal transfer unit that is arranged at one of the output ends of the vertical transfer unit and horizontally transfers the pixel output from the vertical transfer unit. An imaging device comprising:
  Vertical transfer control means for dividing the pixel output vertical transfer into a predetermined period including a horizontal transfer period and performing a plurality of times
  An image pickup apparatus comprising: a horizontal transfer clock control means for temporarily stopping a horizontal transfer clock for a certain period after the falling or rising of the vertical transfer clock, or for a certain period before and after the falling or rising. 4. The image pickup apparatus according to claim 3, further comprising vertical transfer clock control means for alleviating steep rising and falling edges of the vertical transfer clock.

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