JP2017103575A - Two-dimensional ccd imaging apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a two-dimensional CCD imaging apparatus capable of acquiring a detail image of which a SN ratio is high even in an imaging state where it is difficult to acquire the image with high SN ratio.SOLUTION: A two-dimensional ccd imaging apparatus 100 includes: a plurality of light receiving part photodiodes 101 that is arranged in a matrix state in a vertical direction and a horizontal direction; a vertical transfer CCD 103 that acquires a signal charge acquired by the light receiving part; a horizontal transfer CCD 105 that is connected to one end of the vertical transfer CCD; a vertical and horizontal transfer control part 107 that controls a timing of transferring the signal charge from the light receiving part to the vertical transfer CCD and the timing of vertically transferring the signal charge in the vertical transfer CCD. After a reading pulse that transfers the signal charge to the vertical transfer CCD from the light receiving part is transmitted, the vertical and horizontal transfer control part executes an overlapping image processing that transmits the vertical transfer plus that vertically transfers the signal charge of the light receiving part to the vertical transfer CCD before the reading plus is sequentially transmitted.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a two-dimensional CCD imaging device, and more particularly to an apparatus that acquires a detailed image with a high S / N ratio even in an imaging situation where it is difficult to acquire an image with a high S / N ratio.

  The operation of the conventional two-dimensional CCD image pickup apparatus will be described using the CCD solid-state image pickup device 10 shown in FIG. FIG. 8 is a schematic diagram of the solid-state imaging device 2 configured by the CCD solid-state imaging device 10 and an embodiment of a drive control unit 96 that drives the CCD solid-state imaging device 10. In the present embodiment, a case where the interline transfer (IT) type CCD solid-state imaging device 10 is driven in six phases or eight phases will be described as an example.

  In FIG. 8, a drain voltage VDD and a reset drain voltage VRD are applied to the CCD solid-state imaging device 10 from a drive power supply 46, and a predetermined voltage is also supplied to the driver 42.

  The CCD solid-state imaging device 10 constituting the solid-state imaging device 2 includes a sensor unit (photosensitive unit; photocell) 12 including a photodiode as an example of a light receiving element corresponding to a pixel (unit cell) on a semiconductor substrate 21. Are arranged in a two-dimensional matrix in the vertical (row) direction and the horizontal (column) direction. These sensor units 11 convert incident light incident from the light receiving surface into signal charges having a charge amount corresponding to the amount of light, and accumulate the signal charges.

  The CCD solid-state imaging device 10 has a plurality of vertical transfer electrodes 24 (24-1 in this example) corresponding to 6-phase or 8-phase drive for each vertical row of the sensor unit 11 (in this example, 6 or 8 per unit cell). ˜24-6 or 24-1 to 24-8) are arranged in a vertical CCD (V register unit, vertical transfer unit) 13.

  The transfer direction of the vertical CCD 13 is the vertical direction in the figure, the vertical CCD 13 is provided in this direction, and a plurality of vertical CCDs 13 are arranged in a direction (horizontal direction) orthogonal to this direction. Further, a read gate (ROG) 12 is interposed between the vertical CCD 13 and each sensor unit 11. A channel stop CS is provided at the boundary between the unit cells. An imaging area 14 is configured by a plurality of vertical CCDs 13 that are provided for each vertical row of the sensor units 11 and vertically transfer signal charges read from the sensor units 11 by the read gate unit 12.

  The signal charges accumulated in the sensor unit 11 are read out to the vertical CCD 13 by applying a drive pulse corresponding to the readout pulse XSG to the readout gate unit 12. The vertical CCD 13 is driven to transfer by drive pulses φV1 to φV6 (φV8) based on 6-phase (8-phase) vertical transfer clocks V1 to V6 (V8), and the read signal charges are made a part of the horizontal blanking period. Then, the portions corresponding to one scanning line (one line) are sequentially transferred in the vertical direction. This vertical transfer for each line is called a line shift.

  Further, the CCD solid-state imaging device 10 includes a horizontal CCD 15 (H register portion, extending in the horizontal direction in the figure adjacent to each transfer destination side end of the plurality of vertical CCDs 13, that is, adjacent to the vertical CCD 13 in the last row. Horizontal transfer unit) 15 is provided for one line. The horizontal CCD 15 is driven to transfer by drive pulses φH1 and φH2 based on, for example, two-phase horizontal transfer clocks H1 and H2, and the signal charges for one line transferred from the plurality of vertical CCDs 13 are transferred after the horizontal blanking period. The images are sequentially transferred in the horizontal direction during the horizontal scanning period. For this reason, a plurality (two) of horizontal transfer electrodes 29 (29-1, 29-2) corresponding to the two-phase driving are provided.

  At the end of the transfer destination of the horizontal CCD 15, for example, a charge-voltage converter 16 having a floating diffusion amplifier (FDA) configuration is provided. The charge-voltage converter 16 sequentially converts the signal charges transferred horizontally by the horizontal CCD 15 into voltage signals and outputs the voltage signals. This voltage signal is derived as a CCD output (VOUT) corresponding to the amount of incident light from the subject. The interline transfer type CCD solid-state imaging device 10 is configured as described above.

  Further, the solid-state imaging device 2 generates various pulse signals (binary of “L” level and “H” level) for driving the CCD solid-state imaging device 10 as a characteristic part of the solid-state imaging device 2 of the present embodiment. And a driver 42 that supplies various pulses supplied from the timing signal generator 40 to a predetermined level of drive pulses and supplies them to the CCD solid-state imaging device 10. For example, the timing signal generation unit 40 reads out the readout pulse XSG for reading out the signal charges accumulated in the sensor unit 11 of the CCD solid-state imaging device 10 based on the horizontal synchronization signal (VD) and the vertical synchronization signal (VD). Vertical transfer clocks V1 to Vn (n indicates the number of phases at the time of driving; for example, V6 at the time of six-phase driving, V8 at the time of eight-phase driving) for transferring and driving the signal charge in the vertical direction and passing to the horizontal CCD 15 from the vertical CCD 13 Horizontal transfer pulses H1 and H2, a reset pulse RG, and the like for transferring and driving the transferred signal charge in the horizontal direction and passing to the charge-voltage converter 16 are generated and supplied to the driver 42.

  The driver 42 converts various pulses supplied from the timing signal generator 40 into voltage signals (drive pulses) of a predetermined level, or converts them into other signals and supplies them to the CCD solid-state imaging device 10. For example, the n-phase vertical transfer clocks V 1 to V 6 (V 8) generated from the timing signal generation unit 40 are converted into drive pulses φV 1 to φV 6 (φV 8) through the driver 42, and corresponding to each other in the CCD solid-state imaging device 10. It is applied to predetermined vertical transfer electrodes (24-1 to 24-6 or 24-1 to 24-8). Similarly, the two-phase horizontal transfer clocks H1 and H2 are converted to drive pulses φH1 and φH2 via the driver 42, and corresponding predetermined horizontal transfer electrodes (29-1 and 29-2) in the CCD solid-state imaging device 10 are used. To be applied.

  Here, the driver 42 superimposes the read pulse XSG on V1, V3, V5 (, V7) of the six-phase or eight-phase vertical transfer clocks V1 to V6 (V8), thereby setting the ternary level. The obtained vertical drive pulses φV1, φV3, φV5 (, φV7) are supplied to the CCD solid-state imaging device 10. That is, the vertical drive pulses φV1, φV3, φV5 (, φV7) are used not only for the original vertical transfer operation but also for reading the signal charges.

  An outline of a series of operations of the CCD solid-state imaging device 10 having such a configuration is as follows. First, the timing signal generation unit 40 generates various pulse signals such as transfer clocks V1 to V6 (V8) for vertical transfer and a read pulse XSG. These pulse signals are converted into drive pulses of a predetermined voltage level by the driver 42 and then input to predetermined terminals of the CCD solid-state imaging device 10.

  The signal charges accumulated in each of the sensor units 11 are such that the readout pulse XSG emitted from the timing signal generation unit 40 is applied to the transfer channel terminal electrode of the readout gate unit 12, and the potential below the transfer channel terminal electrode is deepened. Thus, the data is read out to the vertical CCD 13 through the readout gate section 12. Then, the vertical CCD 13 is driven on the basis of the six-phase (eight-phase) vertical drive pulses φV1 to φV6 (φV8), and sequentially transferred to the horizontal CCD15.

  The horizontal CCD 15 is sent to one line vertically transferred from each of the plurality of vertical CCDs 13 based on the two-phase horizontal drive pulses φH1 and φH2 emitted from the timing signal generator 40 and converted to a predetermined voltage level by the driver 42. Corresponding signal charges are sequentially horizontally transferred to the charge-voltage converter 16 side.

  The charge-voltage converter 16 accumulates signal charges sequentially injected from the horizontal CCD 15 in a floating diffusion (not shown), converts the accumulated signal charges into a signal voltage, for example, via an output circuit having a source follower configuration (not shown). The image signal (CCD output signal) VOUT is output under the control of the reset pulse RG generated from the timing signal generator 40.

  That is, in the CCD solid-state imaging device 10, the signal charges detected in the imaging area 14 in which the sensor units 11 are arranged two-dimensionally in the vertical and horizontal directions are provided to the vertical CCDs 13 corresponding to the vertical columns of the sensor units 11. Thus, the signal charges are transferred vertically to the horizontal CCD 15, and then the signal charges are transferred in the horizontal direction by the horizontal CCD 15 based on the two-phase horizontal transfer pulses H 1 and H 2. Then, the operation of converting the potential to the potential corresponding to the signal charge from the horizontal CCD 15 by the charge voltage conversion unit 16 and outputting the potential is repeated (see Patent Document 1 above).

JP 2004-328314 A

  The above-described CCD solid-state imaging device 10 has the following points to be improved. In the CCD solid-state imaging device 10, the next signal charge is not acquired in the sensor unit 11 until all the signal charges acquired in the sensor unit 11 are transferred in the horizontal direction via the horizontal CCD 15. For this reason, there is a point to be improved that a detailed image cannot be acquired in an imaging situation where it is difficult to acquire an image with a high S / N ratio, such as a situation where the vehicle moves at high speed.

  Therefore, an object of the present invention is to provide a two-dimensional CCD image pickup apparatus that can acquire a detailed image with a high S / N ratio even in an imaging situation where it is difficult to acquire an image with a high S / N ratio.

  Means for solving the problems in the present invention and the effects of the invention will be described below.

  A two-dimensional CCD imaging device according to the present invention includes a plurality of light receiving units arranged in a matrix in a vertical direction and a horizontal direction, and a vertical transfer CCD for acquiring a signal charge acquired by the light receiving unit, A vertical transfer CCD disposed along the vertical direction, a horizontal transfer CCD connected to one end of the vertical transfer CCD, a timing at which the signal charge is transferred from the light receiving unit to the vertical transfer CCD, and the signal in the vertical transfer CCD A two-dimensional CCD image pickup apparatus having a vertical horizontal transfer control unit that controls a timing of vertical transfer of charges and a timing of horizontal transfer of the signal charges in the horizontal transfer CCD, wherein the vertical horizontal transfer control unit includes: After transmitting a readout pulse for transferring signal charges from the light receiving unit to the vertical transfer CCD, the readout pulse is then transferred. Before sending, performing overlapping image processing of transmitting the vertical transfer pulse to vertically transfer signal charges of the light receiving portion in the direction perpendicular to the vertical transfer CCD, and said.

  Thereby, since the signal charge acquired through the light receiving unit can be amplified, an image with a high S / N ratio can be acquired, and thus a detailed image can be acquired.

  In the two-dimensional CCD imaging device according to the present invention, the vertical and horizontal transfer control unit executes the overlapping imaging process a plurality of times.

  Thereby, since the signal charge acquired through the light receiving unit can be amplified, an image with a high S / N ratio can be acquired, and thus a detailed image can be acquired.

  In the two-dimensional CCD imaging device according to the present invention, the vertical and horizontal transfer control unit further moves an imaging interval time, which is an interval for transmitting the readout pulse, relative to the imaging object of the two-dimensional CCD imaging device. It is characterized in that the moving time for moving the row imaging area for one row in the horizontal direction of the two-dimensional CCD image pickup device at a speed by one row in the vertical direction is set.

  Accordingly, the area that can be imaged in the X-th row imaging area of the two-dimensional CCD imaging device at a certain imaging timing can be matched with the area that can be imaged in the X + 1-th row imaging area at the next imaging timing. That is, the same area can be imaged in different row imaging areas at a plurality of imaging timings. Therefore, in the two-dimensional CCD image pickup device, the signal charge for the same region can be amplified by adding the signal charge of the light receiving unit acquired at each image pickup timing while shifting one line at a time in the vertical direction. , An image with a high S / N ratio can be acquired, and as a result, a detailed image can be acquired.

  An operation control method of a two-dimensional CCD image pickup device according to the present invention is a vertical transfer CCD that acquires a plurality of light receiving units arranged in a matrix in the vertical direction and the horizontal direction, and a signal charge acquired by the light receiving unit, Operation control of the two-dimensional CCD image pickup device for controlling the operation of the two-dimensional CCD image pickup device having a vertical transfer CCD arranged along the vertical direction of the light receiving unit and a horizontal transfer CCD connected to one end of the vertical transfer CCD. In this method, after transmitting a readout pulse for transferring a signal charge from the light receiving unit to the vertical transfer CCD, the signal charge of the light receiving unit is vertically transferred in a vertical direction before transmitting the readout pulse next time. Duplicate image processing for transmitting a vertical transfer pulse to the vertical transfer CCD is performed.

  Thereby, since the signal charge acquired through the light receiving unit can be amplified, an image with a high S / N ratio can be acquired, and thus a detailed image can be acquired.

  The operation control method for a two-dimensional CCD image pickup apparatus according to the present invention is further characterized in that the overlap image pickup process is executed a plurality of times.

  Thereby, since the signal charge acquired through the light receiving unit can be amplified, an image with a high S / N ratio can be acquired, and thus a detailed image can be acquired.

  In the operation control method of the two-dimensional CCD image pickup device according to the present invention, the image pickup interval time that is an interval for transmitting the readout pulse is further set at the relative movement speed of the two-dimensional CCD image pickup device with respect to the object to be imaged. It is characterized in that the moving time for moving the row imaging area for one row in the horizontal direction of the three-dimensional CCD image pickup device by one row in the vertical direction is set.

  Accordingly, the area that can be imaged in the X-th row imaging area of the two-dimensional CCD imaging device at a certain imaging timing can be matched with the area that can be imaged in the X + 1-th row imaging area at the next imaging timing. That is, the same area can be imaged in different row imaging areas at a plurality of imaging timings. Therefore, in the two-dimensional CCD image pickup device, the signal charge for the same region can be amplified by adding the signal charge of the light receiving unit acquired at each image pickup timing while shifting one line at a time in the vertical direction. , An image with a high S / N ratio can be acquired, and as a result, a detailed image can be acquired.

  An operation control program of a two-dimensional CCD imaging device according to the present invention is a vertical transfer CCD that acquires a plurality of light receiving units arranged in a matrix in the vertical direction and the horizontal direction, and a signal charge acquired by the light receiving unit, A vertical transfer CCD disposed along a vertical direction of the light receiving unit, a horizontal transfer CCD connected to one end of the vertical transfer CCD, a timing for transferring the signal charge from the light receiving unit to the vertical transfer CCD, and the vertical transfer A two-dimensional CCD for controlling the operation of a two-dimensional CCD image pickup device having a timing for vertically transferring the signal charge in the CCD and a vertical and horizontal transfer control unit for controlling the timing for horizontally transferring the signal charge in the horizontal transfer CCD. An operation control program for an image pickup device, wherein the operation control program for the two-dimensional CCD image pickup device is The vertical / horizontal transfer control unit transmits the signal charge from the light receiving unit to the vertical transfer CCD and then vertically transmits the signal charge of the light receiving unit in the vertical direction before transmitting the read pulse. It is characterized by functioning to execute a duplicate image processing for transmitting a vertical transfer pulse to be transferred to the vertical transfer CCD.

Thereby, since the signal charge acquired through the light receiving unit can be amplified, an image with a high S / N ratio can be acquired, and thus a detailed image can be acquired.

It is a figure which shows the hardware constitutions of the two-dimensional CCD imaging device 100 which is one Example of the two-dimensional CCD imaging device which concerns on this invention. 2 is a diagram illustrating a relationship between an imaging region of the two-dimensional CCD imaging device 100 and a movement of a device-mounted moving object on which the two-dimensional CCD imaging device 100 is mounted, where A indicates a certain imaging timing and B indicates the next imaging. Indicates timing. 4 is a flowchart showing the operation of the vertical and horizontal transfer control unit 107 of the two-dimensional CCD image pickup apparatus 100. FIG. 3 is a diagram illustrating movement of signal charges in the two-dimensional CCD imaging device 100. 6 is a timing chart of each pulse generated by the vertical and horizontal transfer control unit 107 of the two-dimensional CCD image pickup apparatus 100. 6 is a flowchart showing the operation of the vertical and horizontal transfer control unit 107 of the two-dimensional CCD image pickup apparatus 200. 4 is a timing chart of each pulse generated by the vertical and horizontal transfer control unit 107 of the two-dimensional CCD image pickup apparatus 200. It is a figure which shows the conventional two-dimensional CCD imaging device.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  A two-dimensional CCD (Charge-Coupled Device) imaging device according to the present invention will be described by taking the two-dimensional CCD imaging device 100 shown in FIG. 1 as an example.

First Hardware Configuration A two-dimensional CCD imaging device 100, which will be described with reference to FIG. 1 as an outline of a hardware configuration of the two-dimensional CCD imaging device 100, includes a photodiode 101, a readout gate 102, a vertical transfer CCD 103 (hereinafter, VCCD 103), It has a horizontal transfer CCD 105 (hereinafter referred to as HCCD 105), a vertical and horizontal transfer control unit 107, and a drive power supply unit 109. Note that the two-dimensional CCD image pickup apparatus 100 has the same structure as a so-called interline type CCD image pickup apparatus.

  The photodiode 101 converts incident light incident from the light receiving surface into a signal charge having a charge amount corresponding to the amount of light, and accumulates the signal charge. The photodiodes 101 are arranged on a predetermined substrate in a two-dimensional matrix of M pieces in the vertical direction and N pieces in the horizontal direction, that is, vertical M pixels and horizontal N pixels. For the photodiodes 101 arranged in a matrix, the row farthest from the HCCD 105 is the first row, and the row adjacent to the HCCD 105 is the Mth row. Also,

  The read gate 102 is disposed between the photodiode 101 and the VCCD 103 so as to correspond to each photodiode 101. When the reading gate 102 acquires a predetermined reading pulse, the reading gate 102 transfers the signal charge accumulated in the photodiode 101 to the VCCD 103. The read pulse is provided from the vertical / horizontal transfer control unit 107 at a predetermined timing.

  The VCCD 103 is a kind of MOS structure semiconductor element, and has a plurality of electrodes arranged in series in the vertical direction, and has a semiconductor element 113 (hereinafter referred to as a VCCD element 113) formed corresponding to each electrode. doing. The VCCD 103 sequentially transfers charges accumulated in each VCCD element 113 to the adjacent VCCD elements 113 by controlling the voltage supplied to each electrode. The VCCD 103 is arranged corresponding to each column along a column formed along the vertical direction in the photodiodes 101 arranged in a matrix. The VCCD 103 is driven to transfer in accordance with a predetermined vertical transfer pulse supplied to each electrode, and transfers signal charges acquired from the photodiode 101 in the vertical direction. The VCCD 103 has a plurality of vertical transfer electrodes corresponding to four-phase driving.

  It is assumed that one pixel is constituted by one photodiode 101, the readout gate 102 corresponding to the photodiode 101, and the VCCD element 113. One pixel corresponding to the photodiode 101 in the Xth row and the Yth column is defined as a pixel P (X, Y).

  The HCCD 105 is a kind of MOS-structure semiconductor element, and has a plurality of electrodes arranged in series in the horizontal direction, and has a semiconductor element 115 (hereinafter referred to as an HCCD element 115) formed corresponding to each electrode. doing. The HCCD 105 sequentially transfers the charges accumulated in each HCCD element 115 to the adjacent HCCD elements 115 by controlling the voltage supplied to each electrode. The HCCD 105 is arranged so as to be connected to the ends on the vertical direction side of the plurality of VCCDs 103 arranged in parallel in the vertical direction. The HCCD 105 is driven to transfer in accordance with a predetermined horizontal transfer pulse supplied to each electrode, and transfers the signal charge acquired from the VCCD 103 in the horizontal direction. The HCCD 105 has a plurality of horizontal transfer electrodes corresponding to two-phase driving.

  At one end of the HCCD 105, a charge voltage conversion unit QVC is disposed. For example, a floating diffusion amplifier (FDA) is used as the charge-voltage conversion unit QVC. The charge-voltage converter QVC sequentially converts the signal charges transferred horizontally by the HCCD 105 into voltage signals and outputs the voltage signals. Note that the voltage signal generated by the charge-voltage converter QVC corresponds to a CCD output corresponding to the amount of light incident on the photodiode 101.

  The vertical horizontal transfer control unit 107 operates the read pulse for operating the read gate 102, the vertical transfer pulse for operating the VCCD 103, and the HCCD 105 based on the horizontal synchronization signal (VD) and the vertical synchronization signal (VD). Various pulses such as a horizontal transfer pulse are generated at a predetermined timing. Each pulse transmitted by the vertical and horizontal transfer control unit 107 will be described later.

  Further, the vertical and horizontal transfer control unit 107 stores and holds the imaging interval time Δt and the overlapping imaging count K in a predetermined memory. The imaging interval time Δt indicates an interval from the transfer of the signal charge accumulated in the photodiode 101 to the next transfer, and corresponds to the exposure time for the photodiode 101 to receive light from the outside (see FIG. 5). ). The overlap imaging count K indicates the number of times that the same image is captured at another pixel with respect to an image captured at a certain pixel. Note that the imaging interval time Δt and the overlapping imaging count K can be appropriately rewritten by an instruction from an external controller via a wireless line or a wired line.

The drive power supply unit 109 supplies a predetermined voltage for driving other elements to each element.

Operation of the second two-dimensional CCD image pickup apparatus 100 Outline of Operation The two-dimensional CCD imaging device 100 is mounted on an object to be imaged while moving (hereinafter referred to as a device-mounted moving object). As the device-mounted moving object, for example, there is an artificial satellite that images the ground surface while moving at high speed.

  Since the apparatus-mounted moving object moves, the imaging area of the two-dimensional CCD image pickup apparatus 100 also moves as the apparatus-mounted moving object moves. As shown in FIG. 2A, the row imaging region R100 of the pixels P (X, 1) to P (X, N) in the Xth row at a certain imaging timing is as shown in FIG. 2B at the next imaging timing. It moves along the moving direction of the device-mounted moving object, and becomes a row imaging region R′100.

  At this time, the imaging interval time Δt of the two-dimensional CCD imaging device 100 mounted on the apparatus-mounted moving object is set to be a vertical line imaging area of one row in the horizontal direction of the two-dimensional CCD imaging apparatus 100 at the moving speed of the apparatus-mounted moving object. By matching the moving time for moving in one direction direction, the image captured in the X-th row imaging region R100 at a certain imaging timing is matched with the image captured in the X + 1-th row imaging region R200 at the next imaging timing. be able to. That is, the same image can be acquired in successive row imaging areas at successive imaging timings. That is, it is possible to acquire an image that has been captured in duplicate.

  In the two-dimensional CCD imaging device 100, the signal charges of the photodiode 101 acquired at a predetermined imaging timing are added while being shifted one row at a time in the vertical direction, whereby the signal charges for the same image can be amplified. .

2. Operation Timing The operation of the two-dimensional CCD image pickup apparatus 100 will be described with reference to FIGS. FIG. 3 is a flowchart showing the operation of the vertical and horizontal transfer control unit 107, FIG. 4 shows the movement of the signal charge accompanying each pulse, and FIG. 3 shows the timing of each pulse generated by the vertical and horizontal transfer control unit 107. It is a figure which shows a chart.

  In the two-dimensional CCD image pickup apparatus 100, an overlapping image pickup process for picking up the same image a plurality of times and a CCD image acquisition process for acquiring an image obtained by the overlap image pickup process by the operation of the conventional CCD are executed. To do. As shown in FIG. 3, the vertical / horizontal transfer control unit 107 transmits a refresh pulse for refreshing the signal charges currently stored in the photodiode 101 at a predetermined timing (S301). As a result, the charge remaining in the photodiode 101 can be removed and the photodiode 101 can be reset.

  The vertical and horizontal transfer control unit 107 transmits a read pulse to the read gate 102 after a predetermined imaging interval time Δt has elapsed (S303) (S305). As a result, as shown in FIG. 4, the signal charges accumulated in the photodiodes 101 of the pixels P (L, 1) to P (L, N) corresponding to the Lth row are converted into the pixel P (L, 1). To the VCCD 103 via the electrode of the VCCD element 113 corresponding to each of the pixels P (L, N) (arrow (1)). Note that the vertical and horizontal transfer control unit 107 transmits a read pulse to all the read gates 102 at the same time.

  Returning to FIG. 3, the vertical and horizontal transfer control unit 107 determines whether or not the readout pulse has been transmitted the number of times of repeated imaging, that is, K times (S307). The vertical and horizontal transfer control unit 107 transmits a vertical transfer pulse to the VCCD element 113 when a predetermined time elapses after transmitting the read pulse (S309). As a result, as shown in FIG. 4, the signal charges held by the VCCD elements 113 of the pixels P (L, 1) to P (L, N) corresponding to the Lth row are next adjacent in the vertical direction. Are transferred to the VCCD elements 113 corresponding to the respective pixels P (L + 1, 1) to P (L + 1, N) (arrow (2)). That is, the signal charge held by the VCCD element 113 corresponding to the row imaging area of the Lth row moves to the VCCD element 113 corresponding to the row imaging area of the (L + 1) th row.

  Thereafter, the vertical and horizontal transfer control unit 107 repeats the transmission of the readout pulse with the imaging interval time Δt, the number of times of overlapping imaging, that is, K times. Thus, as shown in FIG. 5, in the two-dimensional CCD image pickup apparatus 100, after the refresh pulse is transmitted, the readout pulse is transmitted K times that is the number of times of repeated imaging, and the signal charge is changed during vertical transfer in the VCCD 103. It can be added K times. The K-th addition of the signal charge is executed by the first vertical transfer of the CCD image acquisition process after transmitting the K-th readout pulse. As described above, after the refresh pulse is transmitted, first, the images acquired at the pixels P (L, 1) to P (L, N) can be overlapped as many times as the number of overlaps. Here, the processing in steps S301 to S309 in the vertical and horizontal transfer control unit 107 corresponds to the overlapping imaging processing.

  Returning to FIG. 3, when the vertical and horizontal transfer control unit 107 determines in step S307 that the read pulse has been transmitted by the number of overlapping imaging, the vertical and horizontal transfer control unit 107 transmits a vertical transfer pulse (S311). Thereafter, the vertical and horizontal transfer control unit 107 transmits a horizontal transfer pulse to the HCCD element 115 (S313). As a result, as shown in FIG. 4, the signal charges that have reached the HCCD element 115 are sequentially transferred to the next HCCD element 115 adjacent in the horizontal direction, and finally, all the signal charges are converted into charge voltage. Part QVC (arrow (a)). The horizontal transfer pulse is transmitted after a predetermined time has elapsed after transmitting the vertical transfer pulse, and the signal charge held by the HCCD element 115 at that time is horizontally transferred.

  Returning to FIG. 3, the vertical and horizontal transfer control unit 107 transmits the vertical transfer pulse in step S <b> 311 and the horizontal transfer pulse in step S <b> 313, that is, the number of pixels in the vertical direction of the two-dimensional CCD imaging device 100, that is, M. Repeatedly (S315). Thereby, by using the two-dimensional CCD image pickup apparatus 100, it is possible to acquire an image obtained by overlappingly imaging the predetermined pixel by the number of times of overlapping imaging. The vertical / horizontal transfer control unit 107 repeats the processes of steps S301 to S315 until the operation ends (S317). Note that the processing in steps S311 to S315 in the vertical and horizontal transfer control unit 107 corresponds to the CCD image acquisition processing and is the same as the operation in the conventional CCD.

As described above, in the two-dimensional CCD image pickup apparatus 100, the signal charge can be added to the number of times of overlapping image pickup during vertical transfer in the VCCD 103. That is, since an image obtained by overlapping imaging can be acquired, an image having a high SN ratio can be acquired. Therefore, even when an image is acquired from an object moving at high speed using the two-dimensional CCD imaging device 100, a clearer image can be acquired.

  In the above-described two-dimensional CCD image pickup apparatus 100, as shown in FIG. 5, the vertical / horizontal transfer control unit 107 transmits a vertical transfer pulse clearly different from the read pulse after a predetermined time has elapsed after transmitting the read pulse. It was decided to. On the other hand, the two-dimensional CCD image pickup apparatus 200 according to the present embodiment transmits a readout pulse in which a readout pulse and a vertical transfer pulse are integrated.

First Hardware Configuration The hardware configuration of the two-dimensional CCD image pickup apparatus 200 is the same as that of the above-described two-dimensional CCD image pickup apparatus 100 (see FIG. 1). However, the operation of the vertical and horizontal transfer control unit 107 is different from that of the two-dimensional CCD image pickup apparatus 100. Hereinafter, the operation of the vertical and horizontal transfer control unit 107 in the two-dimensional CCD image pickup apparatus 200 will be described.

Operation of Second 2D CCD Imaging Device 200 The operation of the 2D CCD imaging device 200 will be described with reference to FIGS. FIG. 6 is a flowchart showing the operation of the vertical and horizontal transfer control unit 107, and FIG. 6 is a timing chart of each pulse generated by the vertical and horizontal transfer control unit 107. In addition, about the operation | movement similar to the two-dimensional CCD imaging device 100 in Example 1, the same code | symbol is attached | subjected and detailed description is abbreviate | omitted.

  Similar to the two-dimensional CCD image pickup apparatus 100, the two-dimensional CCD image pickup apparatus 200 executes overlap image pickup processing and CCD image acquisition processing. As shown in FIG. 6, the vertical and horizontal transfer control unit 107 transmits a refresh pulse for refreshing the signal charges currently stored in the photodiode 101 at a predetermined timing (S301).

  The vertical and horizontal transfer control unit 107 transmits a readout pulse to the readout gate 102 and the VCCD 103 after a predetermined imaging interval time Δt has elapsed (S303) (S605). As shown in FIG. 7, the readout pulse transmitted at this time is a combination of a readout pulse for reading out the signal charge of the photodiode 101 and a vertical transfer pulse for vertically transferring the signal charge of the VCCD 103 corresponding to the readout pulse. It has become.

  Thus, the signal charges accumulated in the photodiodes 101 of the pixels P (L, 1) to P (L, N) corresponding to the Lth row are changed from the pixels P (L, 1) to P (L, N) signal charges transferred to each VCCD element 113 after being transferred to the VCCD 103 via the electrodes of the corresponding VCCD element 113 (see FIG. 4: arrow (1)), the next adjacent in the vertical direction Are transferred to the VCCD element 113 corresponding to each of the pixels P (L + 1, 1) to P (L + 1, N) (see FIG. 4: arrow (2)). In this way, the signal charges held by the photodiodes 101 in the Lth row move to the VCCD elements 113 in the (L + 1) th row. When the signal charge is transferred from the photodiode 101 to the VCCD element 113 and the signal charge exists in the VCCD element 113, the signal charge is added in the VCCD element 113. Further, the vertical / horizontal transfer control unit 107 transmits a read pulse to all the read gates 102 and the VCCD 103 at the same time.

  Returning to FIG. 6, the vertical and horizontal transfer control unit 107 determines whether or not the readout pulse has been transmitted the number of times of overlapping imaging, that is, K times (S307).

  Thereafter, the vertical and horizontal transfer control unit 107 repeats the transmission of the readout pulse with the imaging interval time Δt, the number of times of overlapping imaging, that is, K times. Thus, as shown in FIG. 7, in the two-dimensional CCD image pickup apparatus 200, after the refresh pulse is transmitted, the readout pulse is transmitted K times that is the number of times of repeated imaging, and the signal charge is changed during vertical transfer in the VCCD 103. It can be added K times. The K-th addition of the signal charge is executed by the first vertical transfer of the CCD image acquisition process after transmitting the K-th readout pulse. As described above, after the refresh pulse is transmitted, first, the images acquired at the pixels P (L, 1) to P (L, N) can be overlapped as many times as the number of overlaps. Here, the processes in steps S301 to S605 to S307 in the vertical and horizontal transfer control unit 107 correspond to the overlapping imaging process.

  The processes in steps S311 to S317 in the vertical and horizontal transfer control unit 107 are the same as those in the two-dimensional CCD image pickup apparatus 100 in the first embodiment.

[Other Embodiments]

  (1) Overlap imaging count K and imaging interval time Δt: In the above-described first and second embodiments, the overlap imaging count K and imaging interval time Δt included in the vertical and horizontal transfer control unit 107 can be changed from the outside. However, it is not possible to change, and it is possible to use only the predetermined overlapping imaging count K and imaging interval time Δt.

(2) Device-mounted moving object: In the first and second embodiments, the two-dimensional CCD imaging device 100 is mounted on an artificial satellite that moves at high speed. If it is a case where it moves relatively with respect to a target object, it will not be limited to the thing of illustration. For example, the two-dimensional CCD imaging device 100 may be fixed and the object of the image may move.

  The two-dimensional CCD image pickup device according to the present invention can be used, for example, for ground image pickup from an artificial satellite.

100 Two-dimensional CCD image pickup device 200 Two-dimensional CCD image pickup device 101 Photodiode 102 Read gate 103 Vertical transfer CCD
113 VCCD element 105 Horizontal transfer CCD
115 HCCD element 107 vertical / horizontal transfer control unit 109 drive power supply unit R100 row imaging region R′100 row imaging region R200 row imaging region

Claims (7)

A plurality of light receiving units arranged in a matrix in the vertical and horizontal directions,
A vertical transfer CCD for acquiring a signal charge acquired by the light receiving unit, the vertical transfer CCD being disposed along a vertical direction of the light receiving unit;
A horizontal transfer CCD connected to one end of the vertical transfer CCD;
Vertical control that controls the timing of transferring the signal charge from the light receiving unit to the vertical transfer CCD, the timing of vertical transfer of the signal charge in the vertical transfer CCD, and the timing of horizontal transfer of the signal charge in the horizontal transfer CCD. Horizontal transfer controller,
A two-dimensional CCD imaging device having:
The vertical and horizontal transfer control unit
After transmitting a read pulse for transferring the signal charge from the light receiving unit to the vertical transfer CCD, and before transmitting the read pulse, a vertical transfer pulse for vertically transferring the signal charge of the light receiving unit in the vertical direction. Performing duplicate imaging processing to be sent to the vertical transfer CCD;
A two-dimensional CCD image pickup device. In the two-dimensional CCD image pickup device according to claim 1,
The vertical and horizontal transfer control unit
Performing the duplicate imaging process a plurality of times;
A two-dimensional CCD image pickup device. In the two-dimensional CCD image pickup device according to claim 1 or 2,
The vertical and horizontal transfer control unit further includes:
An imaging interval time, which is an interval at which the readout pulse is transmitted, is set to be a vertical moving direction of a row imaging area corresponding to one row in the horizontal direction of the two-dimensional CCD imaging device at a relative moving speed with respect to an imaging target of the two-dimensional CCD imaging device. A travel time for one line of travel,
A two-dimensional CCD image pickup device. A plurality of light receiving units arranged in a matrix in the vertical and horizontal directions,
A vertical transfer CCD for acquiring a signal charge acquired by the light receiving unit, the vertical transfer CCD being disposed along a vertical direction of the light receiving unit;
A horizontal transfer CCD connected to one end of the vertical transfer CCD;
An operation control method for a two-dimensional CCD image pickup device for controlling the operation of a two-dimensional CCD image pickup device having
After transmitting a read pulse for transferring the signal charge from the light receiving unit to the vertical transfer CCD, and before transmitting the read pulse, a vertical transfer pulse for vertically transferring the signal charge of the light receiving unit in the vertical direction. Performing duplicate imaging processing to be sent to the vertical transfer CCD;
An operation control method for a two-dimensional CCD image pickup device. In the operation control method of the two-dimensional CCD image pickup device according to claim 4,
Performing the duplicate imaging process a plurality of times;
An operation control method for a two-dimensional CCD image pickup device. In the operation control method of the two-dimensional CCD image pickup device according to claim 4 or 5,
An imaging interval time, which is an interval at which the readout pulse is transmitted, is set to be a vertical moving direction of a row imaging area corresponding to one row in the horizontal direction of the two-dimensional CCD imaging device at a relative moving speed with respect to an imaging target of the two-dimensional CCD imaging device. A travel time for one line of travel,
An operation control method for a two-dimensional CCD image pickup device. A plurality of light receiving units arranged in a matrix in the vertical and horizontal directions,
A vertical transfer CCD for acquiring a signal charge acquired by the light receiving unit, the vertical transfer CCD being disposed along a vertical direction of the light receiving unit;
A horizontal transfer CCD connected to one end of the vertical transfer CCD;
Vertical control that controls the timing of transferring the signal charge from the light receiving unit to the vertical transfer CCD, the timing of vertical transfer of the signal charge in the vertical transfer CCD, and the timing of horizontal transfer of the signal charge in the horizontal transfer CCD. Horizontal transfer controller,
An operation control program for a two-dimensional CCD image pickup device for controlling the operation of the two-dimensional CCD image pickup device having
The operation control program of the two-dimensional CCD imaging device is:
The vertical and horizontal transfer control unit;
After transmitting a read pulse for transferring the signal charge from the light receiving unit to the vertical transfer CCD, and before transmitting the read pulse, a vertical transfer pulse for vertically transferring the signal charge of the light receiving unit in the vertical direction. Functioning to perform duplicate imaging processing to be sent to the vertical transfer CCD;
An operation control program for a two-dimensional CCD imaging device.

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