Interline CCD image sensor and method for imaging a moving object using the same

Abstract

To image a high-speed mobile without decreasing the number of pixels.SOLUTION: An interline type CCD image sensor 10 comprises: a plurality of exposure units 12 arrayed in a two-dimensional shape so as to form rows and columns; a plurality of vertical transfer paths 13 respectively disposed in parallel in the rows of the exposure units 12; a horizontal transfer path 15 which is connected to one end of the plurality of vertical transfer paths 13 and to which electric charge is transferred from the vertical transfer paths; and a CCD controller 11 which controls the CCD image sensor in accordance with an operation program 17. An operation of performing exposure in the plurality of exposure units 12 and transferring the electric charges stored in the exposure units by the exposure to the vertical transfer paths 13 is executed repeatedly a plurality of times at predetermined time intervals without transferring the electric charge from the vertical transfer path 13 to the horizontal transfer path 15, and the CCD controller 11 controls exposure and electric charge transfer timing in such a manner that the electric charge repeatedly transferred to the vertical transfer paths 13 is transferred to the horizontal transfer path 15 in predetermined timing and outputted from the horizontal transfer path to the outside.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an interline CCD image sensor and a method for imaging a moving object using the same. [Background technology]

[0002] In recent years, technological development of imaging elements has progressed dramatically, and image sensors capable of high-speed readout with many pixels have been developed, with CMOS image sensors now capable of capturing hundreds of images per second with millions of pixels, making it possible to obtain blur-free images of objects moving at relatively high speeds.

[0003] However, when capturing images during a flyby of a small celestial body moving at extremely high speed, it is necessary to capture thousands of images per second, rather than hundreds, across the entire detection surface of several million pixels. At present, however, it is difficult to capture images of about 1,000 frames per second with several million pixels. For this reason, the number of pixels must be reduced in order to capture images at high speed using a CMOS image sensor. In addition, high-speed imaging consumes a lot of power, making it unsuitable for situations where power is limited, such as imaging from a space probe.

[0004] On the other hand, in addition to CMOS, interline CCDs are also known as image sensors. In an interline CCD, the charge accumulated in the exposure section during exposure is transferred to the vertical transfer path, then to the horizontal transfer path, and the charge of each pixel is read out in sequence. Once this is complete, the next exposure begins, allowing image data to be obtained sequentially. In this way, after all pixels are exposed to light, the charge is transferred sequentially to the vertical and horizontal transfer paths to read out all the pixels' charges, so one exposure takes a certain amount of time.

[0005] A technology has been proposed for capturing images of a fast moving object using this interline CCD image sensor (see Patent Document 1 below). The technology described in Patent Document 1 is such that, in an interline CCD, the imaging interval time Δt of the light receiving unit is set to the moving time for a row imaging area of ​​one horizontal line to move one vertical line at the moving speed of the moving object, and the signal charges of the light receiving unit acquired at each imaging timing are added while shifting the area by one line vertically, thereby acquiring overlapping captured images in which the signal charges for the same area are amplified, and after capturing a predetermined number of overlapping images, the overlapping captured images are read out.

[0006] According to the technology described in Patent Document 1, it is possible to obtain overlapping images captured in consecutive row imaging areas, thereby improving the S / N ratio of images of fast moving objects, for which it is difficult to obtain images with a high S / N ratio.

[0007] However, even when the imaging interval time Δt of the interline CCD image sensor in the technology described in Patent Document 1 is set to the minimum time interval, if the moving object is moving so fast that it moves more than one line, the technology cannot be applied. In addition, imaging must be started when the image of the moving object is on the detection surface, and it is difficult to apply the technology when the exact position of the fast moving object is unknown. Such a situation of high speed movement and a situation where the exact position is unknown can easily occur, for example, in high speed flyby observation of a small celestial body. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] Patent No. 6626605 Summary of the Invention [Problem to be solved by the invention]

[0009] The present invention has been made in consideration of the above-mentioned circumstances, and has as its object to provide an interline CCD that enables easy imaging of fast moving objects without reducing the number of pixels, and a method for imaging a moving object using the interline CCD. [Means for solving the problem]

[0010] In order to solve the above problems, the interline type CCD image sensor of the present invention comprises a plurality of exposure sections arranged two-dimensionally to form rows and columns, a plurality of vertical transfer paths arranged in parallel to each column of the exposure sections, wherein charges accumulated in the exposure sections of each column are transferred to the plurality of vertical transfer paths, and a horizontal transfer path connected to one end of the plurality of vertical transfer paths to transfer charges from the vertical transfer path, wherein the horizontal transfer path sequentially outputs the transferred charges to the outside via the horizontal transfer path, and a control unit for controlling the plurality of exposure sections, the vertical transfer paths, and the horizontal transfer path, and the control unit controls the exposure and charge transfer timing so that an operation of performing exposure at the plurality of exposure sections and transferring charges accumulated in each of the plurality of exposure sections by exposure to the vertical transfer paths is repeated a plurality of times at predetermined time intervals without transferring charges from the vertical transfer paths to the horizontal transfer paths, and the charges repeatedly transferred to the vertical transfer paths are transferred to the horizontal transfer path at a predetermined timing and output from the horizontal transfer path to the outside.

[0011] The object to be imaged by the interline CCD image sensor may be a moving object. In this case, the predetermined time interval is preferably set to a time interval in which the areas of the moving object on the detection surface of the interline CCD image sensor do not overlap. Alternatively, the predetermined time interval may be set so that the areas of the moving object imaged adjacent to each other on the detection surface of the interline CCD image sensor partially overlap each other.

[0012] Preferably, the predetermined timing is set to the timing when the moving object leaves the detection surface of the interline CCD image sensor. Also, the predetermined timing may be when the number of repetitions of the operation reaches a predetermined value.

[0013] For example, the moving object is a solar system object during a flyby. Preferably, the control unit is configured to be able to adjust at least one of the predetermined time interval and the predetermined timing.

[0014] Another aspect of the present invention provides a method for imaging a moving object using an interline CCD image sensor, the interline CCD image sensor comprising a plurality of exposure sections arranged two-dimensionally to form rows and columns, a plurality of vertical transfer paths arranged in parallel to each column of the exposure sections, and a horizontal transfer path connected to one end of the plurality of vertical transfer paths, the method comprising the steps of: performing exposure at the plurality of exposure sections; and transferring charges accumulated in each of the plurality of exposure sections by exposure to the vertical transfer paths, without transferring charges from the vertical transfer paths to the horizontal transfer path. At a given time interval The method includes a multiple exposure process which is repeatedly performed multiple times, a transfer process which transfers the charges repeatedly transferred to the vertical transfer path to the horizontal transfer path at a predetermined timing, and an output process which sequentially outputs the charges transferred to the horizontal transfer path to the outside via the horizontal transfer path.

[0015] Preferably, in the multiple exposure step, the predetermined time interval is set to a time interval in which the areas of the moving object on the detection surface of the interline CCD image sensor do not overlap. Alternatively, in the multiple exposure step, the predetermined time interval may be set so that the areas of the moving object imaged adjacently on the detection surface of the interline CCD image sensor partially overlap.

[0016] Preferably, in the transfer step, the predetermined timing is set to the timing when the moving object leaves the detection surface of the interline CCD image sensor. Alternatively, in the transfer step, the predetermined timing may be when the number of repetitions of the operation reaches a predetermined value.

[0017] For example, the moving object is a solar system object during a flyby. Preferably, at least one of the specified time interval and the specified timing is set in advance based on the expected speed and trajectory of the moving body and the focal length of an optical system attached to the interline CCD image sensor. [Brief description of the drawings]

[0018] [Figure 1] FIG. 1 is a schematic diagram showing the configuration of an interline CCD image sensor according to one embodiment of the present invention. [Diagram 2] FIG. 1 is a schematic diagram illustrating an interline CCD image sensor according to an embodiment of the present invention, applied to flyby observation of a small solar system body, as an example. [Diagram 3] FIG. 3 is a flowchart showing the flow of operations of the interline CCD image sensor according to one embodiment of the present invention. [Figure 4] FIG. 4 is a comparative diagram between an image of a fast moving object captured using a conventional interline CCD image sensor and an image of a fast moving object captured using an interline CCD image sensor according to one embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows a schematic diagram of an interline CCD image sensor 10 according to an embodiment of the present invention. The interline CCD image sensor 10 includes a plurality of exposure sections 12. Each exposure section 12 is composed of a photodiode or a diode having a MOS structure, and when light is irradiated onto each exposure section 12 during a controlled exposure time, a charge is generated by photoelectric conversion, and the charge is accumulated in the junction capacitance of the exposure section 2 itself. The exposure sections 12 are arranged in a horizontal direction to form 1 to m rows, and in a vertical direction to form 1 to n columns, and the m×n exposure sections 12 are two-dimensionally arranged as all pixels. The area covered by the m×n exposure sections 12 defines the detection surface of the interline CCD image sensor 10.

[0020] The interline CCD image sensor 10 also includes a plurality of vertical transfer paths 13 arranged in parallel in each of the first to nth columns of the exposure sections 12, and transfer gates 14 arranged between each column of the exposure sections 12 and the vertical transfer path 13 corresponding to that column. When the transfer gates 14 receive a readout pulse, they open the gate, and the charges accumulated in the exposure sections 12 are transferred to the vertical transfer path 13 through the transfer gates 14. The vertical transfer path 13 is a vertical shift register, which holds the charges transferred from the exposure sections 12 of each column, and transfers the charges sequentially in the vertical direction when a vertical transfer pulse is received.

[0021] Furthermore, the interline type CCD image sensor 10 includes a horizontal transfer path 15 connected to one end of the multiple vertical transfer paths 13, and an image data output section 16. The horizontal transfer path 15 is a horizontal shift register, and upon receiving a horizontal transfer pulse, transfers and outputs the charges for each row that have been sequentially transferred from the vertical transfer paths 13 of each column through the horizontal transfer path 15 to the image data output section 16.

[0022] Furthermore, the interline CCD image sensor 10 is equipped with a CCD controller 11. The CCD controller 11 controls the exposure of the exposure unit 12 described above, and also controls the charge transfer timing of the transfer gate 14, the vertical transfer path 13, and the horizontal transfer path 15 by transmitting a read pulse, a vertical transfer pulse, and a horizontal transfer pulse in accordance with an operation program 17 stored in a memory.

[0023] FIG. 2 shows a schematic diagram of an interline CCD image sensor 10 according to this embodiment applied to flyby observation of a small solar system body as an example. 2, the interline CCD image sensor 10 according to this embodiment is provided in an imaging device 20 arranged inside a probe 30. The imaging device 20 is equipped with an optical lens 21, and the probe 30 is equipped with a probe controller 31 that controls the entire probe including the imaging device 20.

[0024] Information such as the focal length of the optical lens 21 is transmitted to the probe controller 31, which can calculate the angle of view of the imaging device 20 based on the focal length of the optical lens 21 and the size of the detection surface of the interline CCD image sensor 10, and determine the field of view 22 of the imaging device 20. If the focal length of the optical lens 21 is constant, information on the field of view 22 may be stored in advance in the memory of the probe controller 31.

[0025] The probe controller 31 can send an instruction to start imaging to the CCD controller 11 (Figure 1) when a small celestial body 40 (e.g., an asteroid) moving at a relative speed V to the probe 30 enters the field of view 22 of the imaging device 20. At this time, information such as the sensitivity and full well capacity of the interline CCD image sensor 10 is also transmitted to the probe controller 31, and the probe controller 31 can determine the exposure time of the interline CCD image sensor 10 from the luminance information of the small celestial body 40. When the CCD controller 11 receives the instruction to start imaging, it controls the CCD image sensor 10 to start imaging according to the operating program 17.

[0026] The spacecraft controller 31 sends an instruction to end image capture to the CCD controller 11 (FIG. 1) when the small celestial body 40 leaves the field of view 22 of the imaging device 20. Upon receiving the instruction, the CCD controller 11 controls the CCD image sensor 10 to end image capture according to the operating program 17.

[0027] When the distance to the small celestial body 40 is very far, the focal position of the optical lens 21 may be fixed at infinity. Alternatively, the optical lens 21 is adjusted so that the small celestial body 40 falls within the focal depth of the optical lens 21.

[0028] Next, the flow of operations according to the operation program 17 of the interline CCD image sensor 10 according to this embodiment will be described with reference to the flow chart of FIG. As shown in Figure 3, first, a parameter S indicating the number of times of shooting is initialized to 1 (step 100), and the Sth exposure control (step 102) is started. The exposure control is performed so that the exposure sections 12 of all pixels are exposed for the exposure time sent from the probe controller 31 or the exposure time stored in advance in the CCD controller 11. This causes electric charge to accumulate in the exposure sections 12.

[0029] When the exposure is completed, the CCD controller 11 outputs a read pulse to the transfer gate 14, thereby transferring the charges accumulated in the exposure sections 12 of the first to nth columns to the corresponding vertical transfer paths 13 (step 104).

[0030] Next, it is determined whether it is a predetermined timing to complete imaging (step 106). Details of the predetermined timing will be described later. Usually, in the case of the first imaging with s=1, it is not yet time to complete imaging, so a negative determination is made in step 106, and the process proceeds to the next step 108.

[0031] In the next step 108, it is determined whether a predetermined time interval Δt has elapsed since the start of the s-th exposure, and the process waits until Δt has elapsed (negative determination in step 108). If it is determined that the predetermined time interval Δt has elapsed (positive determination in step 108), the number of shots s is incremented by 1 (step 110), and the process returns to step 102, where the second exposure control for s=2 is started.

[0032] Therefore, until a predetermined timing is reached (step 106: positive decision), the exposure of the exposure section 12 and the transfer of charges from the exposure section 12 to the vertical transfer path 13 (steps 102 to 110) are repeated multiple times at a predetermined time interval Δt. A major difference from a conventional interline CCD image sensor is that the exposure of the exposure section 12 and the transfer of charges from the exposure section 12 to the vertical transfer path 13 are performed multiple times without transferring charges from the vertical transfer path 13 to the horizontal transfer path 15. As a result, in the CCD image sensor 10 according to this embodiment, signal charges representing an image of the imaging target (e.g., a small celestial body 40) are accumulated in multiple locations in the vertical transfer path 13. If the imaging target is a small celestial body 40, since it is moving at high speed, by appropriately selecting the time interval Δt, the images of the small celestial body 40 do not overlap each other, and since the background is the dark space of the universe, multiple clear images of the small celestial bodies can be obtained. In this regard, it can be understood that the present invention has an essentially different original purpose, configuration and effect from the technology of Patent Document 1, in which charges are transferred from the exposure section to the vertical transfer path and added together at the time interval that the small celestial body moves one row on the detection surface during a single exposure.

[0033] If it is determined that it is the predetermined timing (YES at step 106), the process proceeds to outputting the charges of the multiple exposure imaging target stored in the 1st to nth vertical transfer paths 13. That is, k, which is the row number of the captured image, is set to m, which is the last row number (step 112), and the charges in each row of the 1st to nth vertical transfer paths 13 are shifted vertically by one row (step 114), and the charge in the kth row of the captured image, that is, the charge in the mth row of the vertical transfer path 13 at the initial point in time, is transferred to the horizontal transfer path 15 (step 118). When these transfer operations are performed, the charge in the mth row of the captured image is stored in the horizontal transfer path 15, and the charge in the rth row (r=1, 2, ..., m-1) of the captured image is stored in the r+1th row of the 1st to nth vertical transfer paths 13.

[0034] Therefore, all charges in the k=mth row of the captured image stored in the horizontal transfer path 15 are transferred and output to the output section 16 (step 118). When this transfer output operation is completed, it is determined whether the row number k of the captured image is 1 (step 120). Since k=m at the current time (negative determination in step 120), k is decremented by 1 to k=m-1 (step 122), and steps 114 to 118 are executed again to transfer charges in the (m-1)th row of the captured image from the vertical transfer path 13 to the horizontal transfer path 15, and from the horizontal transfer path 15 to the output section 16.

[0035] The transfer operations of steps 114 to 122 are repeated until k = 1 (positive determination in step 120), and imaging is completed. This allows all m × n pixels to be output from output unit 16. In the case of the system in Figure 2, the image signal output from output unit 16 is sent to probe controller 31.

[0036] The above is the flow of the operation of the interline CCD image sensor 10 according to this embodiment, but the predetermined timing in step 106 in Fig. 3 may be set to the timing when the moving object to be imaged leaves the detection surface of the interline CCD image sensor 10. For example, when the imaging device 20 in Fig. 2 images a small celestial body 40, the probe controller 31 may predict the orbit of the small celestial body 40 in advance, calculate the time when the small celestial body 40 leaves the field of view range 22 from the line of sight direction and focal length information of the optical lens 21, and notify the CCD controller 11 that the predetermined timing has been reached when the time arrives. In addition, the probe controller 31 may calculate in advance that the image of the moving object can be imaged a predetermined number of times F based on the predicted speed V of the small celestial body 40 and a predetermined time interval Δt, and in step 106, when the number of images s reaches the predetermined number of times F, the multiple exposure process of steps 102 to 110 may be terminated.

[0037] Alternatively, if the exact position of the small celestial body 40 is unknown and it is difficult to determine in advance when it will cross the field of view of the imaging device 20, imaging can be started early and the predetermined number of times F can be set to be greater than the number determined by the speed V and the time interval Δt, so that imaging can be repeated for a long period of time. In this way, if the small celestial body crosses the field of view during that long imaging time, multiple images of the small celestial body can be captured.

[0038] Next, the effects of the embodiment of the present invention will be described. Figure 4 shows a situation where an image of a fast moving object (small celestial body 40) passes over the detection surface in a very short time t (for example, 1 ms) (see the left diagram in Figure 4). Let us consider a situation where an image is captured using an interline CCD during this short time t.

[0039] In the conventional readout method, a short exposure is performed, and after the exposure is completed, the charge is transferred to the vertical transfer path, and then transferred from the vertical transfer path to the horizontal transfer path, and the charges are read out in order, and the next exposure starts after that is completed. However, since it takes a long time to read out the charges of all the pixels, in the case of a CCD image sensor with the conventional readout method, as shown in the center diagram of Figure 4, even if it has an imaging capability of 1000 frames per second and takes a total of 1000 frames continuously in one second, at most one of them can capture an image of a moving object.

[0040] In contrast, in the embodiment of the present invention, after the exposure is completed and the charges are transferred to the vertical transfer path 13, the charges are not transferred to the horizontal transfer path 15, but exposure is performed again and the charges are transferred to the vertical transfer path 13. If the fast moving object to be imaged moves more than the size on the detector between these two exposures, the two images do not overlap and two images can be captured at high speed. If necessary, this operation can be performed multiple times, and after the object to be imaged moves out of the field of view, the charges are transferred to the horizontal transfer path 15 and the charges of all pixels are read out.

[0041] According to the embodiment of the present invention, it is possible to obtain images of all pixels in a much shorter time than the time required to read out all pixels, and it is possible to capture multiple images of a fast moving object in a short time. Therefore, as shown in the right diagram of Fig. 4, in this embodiment, since imaging can be repeated in a shorter time (for example, 10,000 times per second), it is possible to capture changes in the image of the moving object in a very short time. This makes it possible to easily grasp not only the trajectory of the moving object, but also its behavior such as rotation.

[0042] Furthermore, when a CMOS image sensor is used, higher power is required for high-speed imaging than for low-speed imaging. However, this embodiment has the remarkable effect of hardly increasing power consumption.

[0043] The embodiments of the present invention are particularly effective for imaging fast moving objects, and are used, for example, during high-speed flyby observations of solar system objects. During flyby observations, celestial objects cross the field of view at extremely high speeds, so high-speed imaging is required, but with conventional technology, it is not possible to capture images at a sufficient speed with a sufficiently wide field of view and number of pixels, and it is also difficult to continue high-speed imaging in terms of power consumption. With the present invention, it is possible to reduce power consumption and capture images of fast moving objects at very short time intervals. In addition, this technology is also important for detecting fast moving objects and acquiring their shapes on the ground.

[0044] The above is one embodiment of the present invention, but the present invention is not limited to the above example, and can be arbitrarily and suitably modified within the scope of the present invention. For example, moving bodies such as small celestial bodies 40 have been given as examples of imaging targets, but the present invention is not limited to this and can also be applied to objects moving on the ground as described above. Furthermore, the present invention can also be applied to acquiring multiple exposure images of objects whose size, shape, etc. change at high speed. In other words, by applying the present invention to an object that changes shape at high speed while its center of gravity remains stationary, it becomes possible to capture the changes. For this reason, the "moving body" in the present invention includes not only objects whose center of gravity moves, but also objects whose shape changes in the broad sense of the word, in which a part of the object moves its position.

[0045] Also, the process flow of FIG. 3 can be arbitrarily and suitably modified. For example, the predetermined time interval Δt in step 108 of FIG. 3 is set to a time interval in which the regions on the detection surface of the interline CCD image sensor of the moving object do not overlap. However, the present invention is not limited to this example, and the regions may partially overlap. Furthermore, the predetermined time interval Δt may be set so that the regions of the moving object imaged adjacently on the detection surface of the interline CCD image sensor 10 are separated by a certain number of pixels, regardless of whether they overlap, depending on the size of the moving object on the detection surface, for example, so that the regions are separated by two or more rows or two or more columns of the exposure unit 12. Furthermore, it is also possible to change the predetermined time interval Δt during imaging, rather than making it a constant value. [Explanation of symbols]

[0046] 10 Interline CCD image sensor 11 CCD controller 12 Exposure section 13 Multiple (1st to nth columns) vertical transfer paths 14 Transfer Gate 15 Horizontal transfer path 16 Image data output section 17 Operation program 20 Imaging device 21 Optical Lenses 22 Field of view 30. Probe 31 Spacecraft Controller 40 Small celestial bodies in the solar system (fast moving bodies)

Claims

1. An interline type CCD image sensor for capturing an image of a moving object, A plurality of exposure units arranged two-dimensionally to form rows and columns; a plurality of vertical transfer paths arranged in parallel to each column of the exposure sections, the charges accumulated in the exposure sections of each column being transferred to the plurality of vertical transfer paths; a horizontal transfer path connected to one end of the plurality of vertical transfer paths to transfer charges from the vertical transfer paths, the horizontal transfer path sequentially outputting the transferred charges to an outside via the horizontal transfer path; a control unit that controls the exposure units, the vertical transfer path, and the horizontal transfer path; Equipped with the control unit controls timing of exposure and charge transfer so that an operation of performing exposure in the plurality of exposure sections and transferring charges accumulated in each of the plurality of exposure sections by exposure to the vertical transfer path is repeatedly performed a plurality of times at a predetermined time interval without transferring charges from the vertical transfer path to the horizontal transfer path, and the charges repeatedly transferred to the vertical transfer path are transferred to the horizontal transfer path at a predetermined timing and output from the horizontal transfer path to the outside; The control unit is configured to adjust the specified time interval and the specified timing based on at least the predicted speed of the moving body so that there are multiple areas of the moving body that are imaged on the detection surface of the interline CCD image sensor, and when the position of the moving body is unknown, to set the number of times to be greater than the number determined from the predicted speed and the adjusted specified time interval.

2. 2. The interline CCD image sensor according to claim 1, wherein said predetermined time interval is set to a time interval in which respective areas on a detection surface of said interline CCD image sensor of said moving body do not overlap.

3. 2. The interline CCD image sensor according to claim 1, wherein said predetermined time interval is set so that adjacent areas of said moving objects imaged on a detection surface of said interline CCD image sensor partially overlap each other.

4. 4. The interline CCD image sensor according to claim 1, wherein the predetermined timing is set to a timing when the moving object leaves a detection surface of the interline CCD image sensor.

5. 4. The interline CCD image sensor according to claim 1, wherein the predetermined timing is when the number of repetitions of the operation reaches a predetermined value.

6. 6. An interline CCD image sensor according to claim 1, wherein the moving object is a solar system object during a flyby.

7. A method for capturing an image of a moving object using an interline type CCD image sensor, comprising: The interline type CCD image sensor includes: A plurality of exposure units arranged two-dimensionally to form rows and columns; a plurality of vertical transfer paths arranged in parallel to each row of the exposure units; a horizontal transfer path connected to one end of the plurality of vertical transfer paths; Equipped with The method comprises: a multiple exposure process in which an operation of exposing the plurality of exposure sections and transferring charges accumulated in each of the plurality of exposure sections by exposure to the vertical transfer path is repeatedly performed a plurality of times at predetermined time intervals without transferring charges from the vertical transfer path to the horizontal transfer path; a transfer step of transferring the charges repeatedly transferred to the vertical transfer path to the horizontal transfer path at a predetermined timing; an output step of sequentially outputting the charges transferred to the horizontal transfer path to an outside via the horizontal transfer path; Equipped with the method further comprising the steps of adjusting the specified time interval and the specified timing based on the predicted speed and trajectory of the moving body and the focal length of an optical system attached to the interline CCD image sensor so that there are multiple areas of the moving body that are imaged on the detection surface of the interline CCD image sensor, and, when the position of the moving body is unknown, setting the number of times to be greater than the number determined from the predicted speed and the adjusted specified time interval.

8. In the multiple exposure step, 8. The method according to claim 7, wherein the predetermined time interval is set to a time interval in which the regions on the detection surface of the interline CCD image sensor of the moving object do not overlap.

9. In the multiple exposure step, 8. The method according to claim 7, wherein the predetermined time interval is set so that adjacent areas of the moving objects imaged on the detection surface of the interline CCD image sensor partially overlap each other.

10. In the transfer step, 10. The method according to claim 7, wherein the predetermined timing is set to a timing at which the moving object leaves a detection surface of the interline CCD image sensor.

11. In the transfer step, The method according to claim 7 , wherein the predetermined timing is when the number of repetitions of the action reaches a predetermined value.

12. 12. The method according to any one of claims 7 to 11, wherein the moving object is a solar system object during a flyby.

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