JP4367831B2 - Color imaging apparatus and solid-state imaging apparatus drive control method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a color imaging device and a driving control method for a solid-state imaging device, and in particular, selects whether or not to perform an operation of sweeping excess charge immediately before transfer when transferring the charge accumulated in a solid-state imaging device. The present invention relates to an interlaced transfer type color imaging device and a solid-state imaging device drive control method.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, a color imaging device frequently uses a CCD (Charge Coupled Device) in which a plurality of electrodes are arranged on a semiconductor via an insulator as a solid-state imaging device. As a CCD system, in particular, in a solid-state imaging device using an interlace transfer type CCD, a transfer path prior to a transfer operation is conventionally performed when charges accumulated in the solid-state imaging device are transferred as image data. The operation of sweeping out the surplus charge accumulated in the substrate at a high speed (surplus charge sweeping operation) is performed. From the viewpoint of the cause of the occurrence, the surplus charge includes a surplus charge generated when strong light called smear enters the CCD, a surplus charge generated by noise such as dark current, and the like.
This high-speed sweeping of surplus charge is an important technology that forms a part of the drive control method for solid-state imaging devices, but in recent years the cycle of the operation clock when data is taken out from the transfer path tends to become increasingly faster. Consume power. Further, as shown in FIG. 6 to be described later, since the sweeping operation itself takes time, it takes a long time to complete the interlace transfer.
[0003]
The operation of the three-field interlace transfer method in the conventional color imaging device will be described below.
FIG. 6 is a timing chart showing the operation of the three-field interlace transfer method in the conventional color imaging apparatus.
In the figure, conventionally, high-speed sweeping of excess charge removal is performed in all fields.
Next, the operation of the two-field interlace transfer method in the conventional color imaging apparatus will be described with reference to FIG.
FIG. 7 is a timing chart showing the operation of the two-field interlace transfer method in the conventional color imaging apparatus.
As shown in the figure, in the case of 2-field transfer, high-speed sweep is performed only twice. Therefore, even if it is configured not to perform one of them, it cannot greatly contribute to speeding up.
As the above-described high-speed sweeping method of surplus charge, the transfer clock pulse applied to the vertical transfer register of the signal charge storage unit is stopped during the surplus charge sweeping transfer period, and the potential in the vertical transfer register is transferred to the vertical transfer of the imaging unit. A technique is disclosed in which power consumption is reduced by sweeping and transferring surplus charges while being fixed at a deeper potential than the low-level potential of the register (for example, Patent Document 1).
[0004]
In addition, smear charges are swept out before exposure, and the vertical CCD is stopped during exposure so that smear charges generated during the exposure period do not move the vertical CCD. A technique for preventing the occurrence of a ghost image and sweeping smear charges immediately before exposure to prevent the image from blurring is disclosed (for example, Patent Document 2).
Further, in order to prevent the shutter mechanism from requiring high speed, smear charge sweeping is performed by blocking exposure light and darkening the light receiving surface during a charge readout period that is longer than the period during which image charge is generated. A technique for suppressing the generation of smear charges during the period is disclosed in Patent Document 3 below.
[0005]
[Patent Document 1]
Japanese Patent No. 3158324
[Patent Document 2]
JP-A-8-168033
[Patent Document 3]
JP 9-46598 A
[0006]
[Problems to be solved by the invention]
As described above, the conventional solid-state imaging device has a problem that high-speed sweeping of surplus charges consumes a large amount of power because the cycle of the operation clock when extracting data from the transfer path tends to become faster and faster. It was.
Further, since the sweeping operation itself takes time, there is a problem that the time until completion of interlace transfer becomes long.
Furthermore, each of the elements corresponding to the enormous number of pixels included in a solid-state imaging device represented by a CCD has a slight variation in photoelectric effect characteristics, and the sensitivity and the magnitude of dark current are slightly different for each pixel. . For this reason, there is a case where the surplus charge of the noise component cannot be completely removed, and conventionally, the surplus charge that could not be removed has a problem that the image quality is deteriorated.
The techniques disclosed in the above-mentioned Patent Documents 1 to 3 disclose high-speed sweep transfer for sweeping excess charges accumulated in a transfer path or the like prior to transfer and exposure. There is no disclosure of a method for preventing high-speed sweep transfer from being performed in part of frame transfer of race transfer.
[0007]
  The object of the first aspect of the present invention is to reduce the time required to read out all the fields depending on the case, and also to the case where the period of the operation clock when extracting data from the transfer path is high. Depending on the system, high power consumption can be avoided, and high-speed operation is guaranteed and image quality is not degraded.HighOnly in continuous shooting where high speed operation is required, the excess charge sweep-out operation is omitted to guarantee high-speed operation. In normal shooting, color that can provide high image quality by performing conventional operation. An imaging device is provided.
[0008]
  Further claims of the present invention2In particular, the object of the present invention is to provide a color imaging apparatus that can guarantee high-speed operation and realize low power consumption.
  Further, the claims of the present invention3The purpose of this is to reduce the time required to read out all the fields, and in some cases even if the operation clock cycle when extracting data from the transfer path is high-speed, in some cases, large power is not consumed. ,In particular,Like continuous shootingAn object of the present invention is to provide a drive control method for a solid-state imaging device that can guarantee high-speed operation and can provide high image quality by performing control so as to perform conventional operation in the case of normal shooting.
[0009]
  TheFurthermore, the claims of the present invention4The purpose of is to reduce the time until all fields are read out, and even when the period of the operation clock when extracting data from the transfer path is high speed, in some cases, it can avoid consuming a large amount of power. Another object of the present invention is to provide a drive control method for a solid-state imaging device capable of guaranteeing high-speed operation and realizing low power consumption.
[0010]
[Means for Solving the Problems]
  In order to achieve the above-described object, the color imaging device according to the first aspect of the present invention has a charge of all pixels stored in response to a photographed image passing through a plurality of color filters of three or more fields. In a color imaging device comprising: a solid-state imaging device of an interlace transfer method that transfers data divided into a plurality of fields; and a control means of the interlace transfer method that controls the solid-state imaging device;
  Surplus charge sweeping execution means for removing surplus charges from a transfer path used for the data transfer in a data transfer period corresponding to each of the plurality of fields;
  Surplus charge sweep-out non-execution means that does not remove the surplus charge in the data transfer period;
  Prior to the data transfer corresponding to each of the plurality of fields, setting means capable of setting which of the surplus charge sweep execution means and the surplus charge sweep non-execution means should be applied;
  With,
  In the continuous shooting mode in which high-speed continuous shooting is performed, the surplus charges are removed by the surplus charge sweeping execution means during the data transfer period in the first field among the plurality of fields, and the fields after the second field In the data transfer period, the surplus charge is not removed by the surplus charge sweeping non-execution means,
In the case of the normal photographing mode, the surplus charge is removed by the surplus charge sweeping execution means during the data transfer period in all the fields of the plurality of fields.
  It is characterized by that.
[0011]
  TheAnd claims2The color imaging device according to the present invention described inIn order to achieve the above-mentioned purpose,An image pickup apparatus using an image pickup device in which the charge data transfer is divided into a plurality of fields of three or more fields and a plurality of color filters are provided when transferring charges of all the pixels accumulated in the image pickup device. And
  An image sensor of an interlace transfer method including a color signal composed of at least RGB or YeCyMgG in transfer data of each field for transferring the charge;
  Image sensor control means for controlling the data transfer;
  Image processing means for performing image processing with transfer data of an arbitrary number of fields transferred in the plurality of fields,
  In the imaging apparatus capable of setting whether or not the surplus charge removal operation of the transfer path is performed before data transfer to each field, the image sensor control means,
  Of the plurality of fieldsat leastonePartfieldUsing data transferred fromWhen performing image processing, in all fields used in the image processingAboveIt is characterized in that the excess charge removal operation is not performed.
[0012]
  Claim3In order to achieve the above-described object, the drive control method for the solid-state image pickup device according to the present invention described in 1) has a charge for all pixels accumulated by receiving a photographed image through a plurality of color filters of three or more fields. In the drive control method of the solid-state imaging device of the interlace transfer method in which data transfer is divided into a plurality of fields,
  A surplus charge sweeping step for removing surplus charge from a transfer path used for data transfer in a data transfer period corresponding to each of the plurality of fields; and a surplus charge not removing the surplus charge in the data transfer period Sweep-out non-execution step;
  Prior to the data transfer corresponding to each of the plurality of fields, a setting step capable of setting which of the excessive charge sweeping execution step and the excessive charge sweeping non-execution step should be applied;
  With,
  In the continuous shooting mode in which high-speed continuous shooting is performed, the surplus charge is removed by the surplus charge sweeping execution step in the data transfer period in the first field, and the fields after the second field in the plurality of fields. In the data transfer period, the excess charge is not removed by the excess charge sweep-out execution step,
In the normal photographing mode, the surplus charge is removed by the surplus charge sweeping execution step in the data transfer period in all the fields of the plurality of fields.It is characterized by that.
[0013]
  TheAnd claims4The solid-state imaging device drive control method according to the present invention described inIn order to achieve the above-described object, an interlaced transfer type solid state in which the charges for all the pixels accumulated by receiving a photographed image through a plurality of color filters are transferred in a plurality of fields of three or more fields. In the drive control method of the imaging device,
A surplus charge sweeping step for removing surplus charge from a transfer path used for data transfer in a data transfer period corresponding to each of the plurality of fields; and a surplus charge not removing the surplus charge in the data transfer period Sweep-out non-execution step;
Prior to the data transfer corresponding to each of the plurality of fields, a setting step capable of setting which of the excessive charge sweeping execution step and the excessive charge sweeping non-execution step should be applied;
With
  Three primary color data of primary color system or complementary color system are recorded together in each of the plurality of fields, and data transferred from all the fields of the plurality of fields or a part of the plurality of fields is recorded. When image processing is performed continuously using the data transfer, the data transfer of all the fields used is performed.DeadlineIn the meantime, control is performed so as not to remove the surplus charge by applying the non-execution step of sweeping out surplus charge.
[0014]
[Action]
  That is, this departureClearlyThe color imaging device according to the present invention includes an interlaced transfer type solid-state imaging device in which charges for all pixels accumulated by receiving a captured image through a plurality of color filters are transferred in a plurality of three or more fields. In the color imaging device comprising the interlace transfer control means for controlling the solid-state imaging device,
  Surplus charge sweeping execution means for removing surplus charges from a transfer path used for the data transfer in a data transfer period corresponding to each of the plurality of fields;
  Surplus charge sweep-out non-execution means that does not remove the surplus charge in the data transfer period;
  Prior to the data transfer corresponding to each of the plurality of fields, setting means capable of setting which of the surplus charge sweep execution means and the surplus charge sweep non-execution means should be applied;
  Further, prior to the execution of the data transfer corresponding to each of the plurality of fields, it is possible to set which of the surplus charge sweeping execution means and the surplus charge sweeping non-execution means should be applied. With such a configuration, for a specific field of the plurality of fields, in some cases, a high-speed surplus charge sweeping operation is not performed, thereby shortening the time until all the fields are read, Even in the case where the cycle of the operation clock when data is taken out from the transfer path is high speed, large power is not consumed in some cases. In addition, from the solid-state imaging device, when the charges for all the pixels accumulated corresponding to the captured image through the plurality of color filters are transferred in three or more fields, The excess charge sweep-out during the data transfer period of some fields is omitted to ensure high-speed operation and to prevent image quality degradation.
  That is, in the case of transferring in two fields, since the time required for one transfer is long, the influence of noise such as dark current becomes large, and the deterioration of image quality becomes remarkable. On the other hand, when the transfer is divided into three or more fields, the time for collecting noise such as dark current in the transfer path is shortened, so that the influence on the image quality is also reduced. In general, as the number of field divisions increases, the influence of noise on the transfer path decreases. Therefore, when the charges for all the pixels accumulated corresponding to the photographed image are transferred in three or more fields, the excess charge sweeping operation is performed during the data transfer period of some of the fields. Is omitted so that high speed operation is possible and image quality is not deteriorated.
[0015]
    In addition, this departureClearlyThe color imaging device according to the present invention sets a field other than the first field among the plurality of fields as a field to which the excess charge sweep-out execution step is applied during the data transfer execution period. Thus, for fields other than the first field, the time for reading out all the fields is shortened by omitting the high-speed surplus charge sweeping operation, and the cycle of the operation clock when the data is taken out from the transfer path. Even when the speed is high, consumption of large power can be easily avoided.
[0016]
  In addition, this departureClearlyWhen the high-speed continuous shooting is performed, the color imaging device according to the present invention applies the surplus charge sweep-out non-execution means in the data transfer execution period in at least one of the plurality of fields. Avoid removing excess charge. That is, the surplus charge due to smear can be removed by the surplus charge sweeping operation of the first field, but the surplus charge due to noise such as dark current affects each field. In order to eliminate this, correction is normally performed using an OB (Optical Black) integral value, but it may not be able to be completely removed due to inter-element variation of each CCD element. In this case, the high-speed operation is ensured by omitting the surplus charge sweep-out operation only, and in the case of normal shooting, high-quality images can be provided by performing the conventional operation.
[0017]
  In addition, this departureClearlyAccording to the color image pickup apparatus, when transferring the charges of the total number of pixels accumulated in the image pickup device, the charge data transfer is divided into a plurality of fields of three or more fields, and an image pickup device provided with a plurality of color filters An interlaced transfer type image pickup device including at least a color signal of RGB or YeCyMgG in transfer data of each field for transferring electric charge, an image pickup device control means for controlling the data transfer, and the plurality of fields Image processing means for performing image processing with transfer data of an arbitrary number of transferred fields, wherein the image sensor control means performs a surplus charge removal operation on the transfer path before transferring data to each field. It is possible to set whether or not, and when image processing is performed in some or more of the plurality of fields The, is not carried out the excess charges removing operation in all the fields used in the image processing.
[0018]
  That is, image processing is possible for each field alone in a CCD in which all the charges corresponding to RGB signal components in a primary color CCD and YeCyMgG signal components in a complementary color CCD are prepared in each field in interlaced division transfer. When image processing is continuously performed on each field, exposure of the second field is performed during the first field transfer, and the mechanical shutter, which is a light shielding unit, remains open during the transfer. In such a case, smear cannot be removed even if high-speed transfer is performed. Therefore, in such a mode, high-speed operation is enabled and low power consumption is realized by not performing high-speed sweeping which is an operation for removing surplus charges.
  In addition, this departureClearlyThe solid-state imaging device drive control method is based on an interlaced transfer method in which the charges for all the pixels received and stored through a plurality of color filters are transferred in three or more fields. In the solid-state imaging device drive control method, a surplus charge sweeping execution step of removing surplus charges from a transfer path used for data transfer in a data transfer execution period corresponding to each of the plurality of fields, and The surplus charge sweeping non-execution step that does not perform the surplus charge sweeping means in the execution period, and further, prior to the execution of the data transfer corresponding to each of the plurality of fields, the surplus charge sweep execution step, It is possible to set which of the above-mentioned excessive charge sweeping non-execution steps should be applied.
[0019]
  With such a configuration, a specific field of the plurality of fields is controlled so as not to perform a high-speed surplus charge sweeping operation in some cases, thereby shortening the time until all the fields are read out. At the same time, even when the period of the operation clock when extracting data from the transfer path is high speed, large power is not consumed in some cases.
  In addition, this departureClearlyAccording to the solid-state imaging device drive control method, the charges for all the pixels accumulated corresponding to the captured image through the plurality of color filters are transferred from the solid-state imaging device in three or more fields. In this case, a control method that eliminates the excess charge sweeping out during the data transfer period of some of the fields is applied to enable high-speed operation and to prevent image quality degradation. That is, in the case of transferring in two fields, since the time required for one transfer is long, the influence of noise such as dark current becomes large, and the deterioration of image quality becomes remarkable. On the other hand, when the transfer is divided into three or more fields, the time for collecting noise such as dark current in the transfer path is shortened, so that the influence on the image quality is also reduced. In general, as the number of field divisions increases, the influence of noise on the transfer path decreases. Therefore, when charges for all the pixels accumulated corresponding to the photographed image are transferred in three or more fields, the excess charge sweeping operation during the data transfer period of some of the fields is performed. Is applied to control high-speed operation and to prevent image quality degradation..
  MaThe main departureClearlyAccording to the solid-state imaging device drive control method, the field other than the first field among the plurality of fields is set as a field to which the excess charge sweep-out non-execution step is applied during the data transfer execution period. In the execution period, the time for reading out all the fields can be shortened and the data can be taken out from the transfer path so that the sweeping of the surplus charge in the data transfer period of the fields other than the first field can be omitted. Even when the period of the operation clock is high, consumption of large power can be easily avoided.
[0020]
  In addition, this departureClearlyIn the solid-state imaging device drive control method according to the present invention, when high-speed continuous shooting is performed, the surplus charge sweep-out non-execution step is performed in the data transfer execution period in at least one of the plurality of fields. The application is controlled so as not to remove the excess charge. That is, the surplus charge due to smear can be removed by the surplus charge sweeping operation of the first field, but the surplus charge due to noise such as dark current affects each field. In order to eliminate this, correction is normally performed using an OB (Optical Black) integral value, but it may not be able to be completely removed due to inter-element variation of each CCD element. In this case, the high-speed operation is ensured by omitting the surplus charge sweeping operation only, and in the case of normal photographing, it is possible to provide high image quality by controlling the conventional operation.
[0022]
  In addition, this departureClearlyIn the solid-state imaging device drive control method according to the present invention, three primary color data of primary color or complementary color light are recorded in each of the plurality of fields, and all the fields of the plurality of fields or of the plurality of fields are selected. In the case where image processing is continuously performed using data transferred from some fields, the excess charge sweep-out non-execution step is applied during the data transfer execution period of all the fields used. Control is performed so as not to remove the surplus charge. That is, image processing is possible for each field alone in a CCD in which all the charges corresponding to RGB signal components in a primary color CCD and YeCyMgG signal components in a complementary color CCD are prepared in each field in interlaced division transfer. When image processing is continuously performed on each field, exposure of the second field is performed during the first field transfer, and the mechanical shutter, which is a light shielding unit, remains open during the transfer. In such a case, smear cannot be removed even if high-speed transfer is performed. For this reason, in such a mode, control is performed so as not to perform high-speed sweeping, which is a surplus charge removal operation, thereby enabling high-speed operation and low power consumption.
[0023]
DETAILED DESCRIPTION OF THE INVENTION
The principle of the present invention is to realize a low power consumption solid-state imaging device capable of high-speed operation and a control method for the solid-state imaging device by not performing high-speed sweep transfer in a part of interlaced frame transfer. Features.
Hereinafter, based on an embodiment of the present invention, a color imaging device and a solid-state imaging device drive control method of the present invention will be described with reference to the drawings.
FIG. 1 is a block configuration diagram showing a configuration of a main part of a color imaging apparatus according to an embodiment of the present invention.
In the figure, a color imaging apparatus according to an embodiment of the present invention includes a mechanical shutter (abbreviation of “mechanical shutter”, the same shall apply hereinafter) and an imaging lens system 1 for connecting images to be photographed, and a photographed image as a video signal. A CCD 2 for converting to a digital signal, an F / E unit 3 for converting a video signal into a digital signal, a signal processing IC 4 for processing the video signal of the digital signal, an SDRAM 5 for storing the processing result of the signal processing IC 4, and the entire system. In addition, a CPU 10 that creates JPEG image data, an operation unit 6 for inputting a photographing request, a shutter driver / motor driver 7 that controls the lens system 1 including a mechanical shutter, and a display unit that displays a video signal as a video. 8 and a memory card 9 for storing JPEG image data.
[0024]
The F / E unit 3 samples a CDS 31 that samples the output from the CCD 2 under the control of a TG 34, which will be described later, an AGC 32 that adjusts the output of the video signal, an A / D 33 that converts the analog video signal into a digital video signal, And TG 34 for generating drive timings of the components of the CCD 2 and the F / E unit 3.
The signal processing IC 4 includes a CCD-I / F 41 that extracts image feature data, a memory controller 42 that controls the supply destination of the image data and distributes the image data, and a display unit I / that delivers the image data to the display unit 8. F44, YUV conversion part 43 which converts RGB (red, green, blue which is three primary colors of light) data into YUV data, and compression block 45 which carries out JPEG compression of YUV data are provided.
The SDRAM 5 includes a RAW-RGB 51 that records RGB data, a YUV 52 that records YUV data, and a JPEG 53 that records JPEG data.
In the present invention, the CCD 2 is generally an interlace transfer type imaging apparatus that divides the electric charge accumulated in the imaging element into a plurality of fields. In this embodiment, the CCD 2 is assumed to be a 3 million pixel primary color three-time transfer interlaced CCD.
[0025]
Hereinafter, functions of the color imaging apparatus according to the embodiment of the present invention will be described.
When a user's photographing request is input from the operation unit 6, the CPU 10 sets a recording exposure setting for the F / E unit 3. Further, when the set exposure is completed, the CPU 10 controls the shutter driver 7 to close the mechanical shutter of the imaging lens system 1 and shield the CCD 2 from light.
A photographed image that is incident from a photographing object (not shown) through the imaging lens system 1 and formed on the imaging surface of the CCD 2 is extracted from the CCD 2 as an analog image signal and input to the F / E unit 3. . The analog image signal is converted into a digital signal by the F / E unit 3 (having the CDS 31, AGC 32, and A / D 33 as described above), and is taken into the SDRAM 5 through the CCD-I / F 41 of the signal processing IC 4. At this time, the image feature data is extracted by the YUV conversion unit 43 of the CCD-I / F 41. This feature data is used for white balance setting at the time of YUV conversion.
[0026]
FIG. 2 is a front view showing the image plane of the CCD of the color imaging apparatus according to the embodiment of the present invention.
As shown in the figure, the imaging surface of the CCD 2 is composed of an effective pixel range area which is a part actually used for recording, and an area where light is not incident due to metal masking. There is a region in a range where OB (Optical Black) integration is performed as a part of a region in which light is not incident due to metal masking. This OB portion data is also taken into the CCD-I / F 41 together with the effective pixel data.
The data of the OB portion is a charge accumulated in a state where no light is applied, and mainly corresponds to an excess charge due to a dark current.
In the CCD-I / F 41, the data of the OB portion is integrated for several pixels, for example, 8 × 8 pixels, and the average value is obtained. As shown by the arrows in FIG. By subtracting the average value of the OB portion from the pixel data, the extra charge due to noise such as dark current is removed from the pixel data.
[0027]
The RGB data stored in the SDRAM 5 after the completion of the three-field transfer is converted into YUV data by the YUV converter 43 and written back to the SDRAM 5.
When this RGB data is converted into YUV data, the CPU 10 calculates white balance coefficients and edge enhancement coefficients using the feature data extracted by the CCD-I / F 41, and the results are used for white balance and edge enhancement control. used. The YUV data written back to the SDRAM 5 is read again, JPEG compressed in the compression block 45, and written back to the SDRAM 5.
The YUV data compressed in JPEG in the SDRAM 5 is finished with JPEG image data by adding header data or the like by the CPU 10 and stored in the memory card 9.
[0028]
  FIG. 3 is a timing chart showing an operation in the case of the three-field interlace transfer method of the color imaging apparatus according to the embodiment of the present invention.
In the conventional method, as shown in FIG. 6 described above, high-speed sweeping of excess charge removal is performed in all fields.(The remainderIn the color imaging apparatus according to the embodiment of the present invention, for example, as shown in FIG. 3, high-speed sweeping is performed only on the first field. Thus, for example, by performing high-speed sweeping only on the first field, it is possible to remove smear, which is surplus charge generated when the mechanical shutter at the time of exposure is open. In addition, since the high-speed sweep is not performed on the fields after the second field, it is possible to shorten the time until all the pixels are transferred. Further, by omitting the high-speed sweep for the fields after the second field in this way, the power consumed by the high-speed sweep is saved twice.
[0029]
  Less than,According to the embodiment of the present inventionThe operation of the color imaging device will be described.
  hereIn the color image pickup apparatus described in (1), it is possible to set for each of the plurality of fields whether or not the excess charge is to be swept out during interlace transfer, and to operate according to this setting.
  In the color imaging apparatus according to the present embodiment, the setting of whether or not to perform high-speed sweeping during interlace transfer is performed by the CPU 10, and this setting is also performed by the F / E unit that controls the operation of the CCD 2. 3 is done.
  For example,As shown in FIG. 3, among the plurality of fields, fields other than the first field are set as fields in which the high-speed sweep operation is not performed.
[0030]
  Furthermore, according to another embodimentIn the aspect of the color imaging device, when high-speed continuous shooting is performed, the surplus is applied by applying the high-speed sweep execution means in the data transfer execution period in at least one field among the plurality of fields. The charge is removed.
  More specifically, for example, a continuous shooting mode and a normal shooting mode are provided, and the control content is changed as described above according to these two modes. This mode switching can be set by the operation unit 6.
  As described above (see FIG. 2), it has been described that noise components such as dark current are removed by the average value obtained from the OB integration. However, each element corresponding to 3 million pixels included in the CCD 2 has its photoelectric. There are some variations in the effect characteristics, and the sensitivity and the magnitude of dark current differ slightly from pixel to pixel. For this reason, there is a case where the surplus charge of the noise component cannot be completely removed, and conventionally, the surplus charge that could not be removed has a problem that the image quality is deteriorated.
[0031]
  Therefore,According to the inventionIn the aspect of the color imaging device, in order to cope with this problem, in the continuous shooting mode that requires high-speed continuous shooting, drive control is performed so as not to perform high-speed sweeping in some fields of the present invention, In the normal shooting mode, mode-compatible drive control is switched such that drive control is performed as before to obtain high image quality. This achieves high speed in continuous shooting mode.The
  BookIn the aspect of the color imaging device of the present invention, specifically, when the number of divided transfers of interlace transfer is 3 fields or more, the drive control method of the solid-state imaging device according to the embodiment of the present invention is applied, that is, the field Among them, the surplus charge sweeping out operation in the data transfer period of some fields is omitted.
  In general, a CCD that performs interlaced transfer normally performs thinning transfer in the vertical direction. That is, in the case of two-field transfer, odd-numbered lines are transferred as the first field, and even-numbered lines are transferred as the second field. In the case of a 3 million pixel CCD, at least vertical 1536 lines of data are transferred as effective pixels, so the number of transfer lines per field is 768 lines. In the case of 3-field transfer, there are 512 lines per field.
[0032]
When this number of lines increases, the number of stages of CCDs that perform vertical transfer increases, so the possibility of accumulation of noise components increases. From this point of view, the number of interlaced transfer division transfers is 3 fields. In the above case, it is advantageous to apply the drive control method of the solid-state imaging device according to the present invention (that is, omitting the surplus charge sweeping operation during the data transfer period of some of the fields).
As shown in FIG. 7 (conventional example) described above, in the case of two-field transfer, high-speed sweeping is performed only twice. In this case, the color imaging device drive control method according to the embodiment of the present invention is used. Even if one of the high-speed sweeps is not performed by applying the above, it is not possible to greatly contribute to the high speed. Therefore, in the case of a two-field transfer CCD, as in the conventional case, performing high-speed sweeping for all fields (that is, two fields) is less advantageous in image quality deterioration and has a great advantage.
[0033]
  On the other hand, in the case of split transfer with three or more field transfers where the number of vertical transfer stages is small and the number of high-speed sweeps is large, reducing the number of high-speed sweeps increases the effect of high speed and power saving, so that three-field splits The driving method of the color imaging apparatus according to the embodiment of the present invention is applied to the above interlace transfer type CCD.
  Less than,ThisThe operation of the color imaging apparatus will be described.
  ThisIn the aspect of the color imaging apparatus, the primary color data or the complementary primary color light data is recorded in each of the plurality of fields, and all the fields of the plurality of fields or a part of the plurality of fields is recorded. In the case where image processing is continuously performed using data transferred from one field, the excess charge is not removed during the data transfer execution period of all the fields used.
  More specifically, for example, in the case of a three-field transfer CCD, control is performed so that high-speed sweeping is not performed for each field when signal processing is performed continuously by only one transfer. It is.
[0034]
FIG. 4 is an explanatory diagram showing the transfer operation of each field data of the CCD when performing three-field transfer in the color imaging apparatus according to the embodiment of the present invention.
As shown in the figure, in this aspect, since R, G, and B data are prepared for each field, YUV conversion is possible with only one field (and therefore one transfer).
Hereinafter, an operation in the case of capturing continuous images by converting the RGB data for one field by YUV will be described.
FIG. 5 is a timing chart showing an operation in the case of capturing continuous images by YUV converting RGB data for one field in the color imaging apparatus according to the embodiment of the present invention.
As shown in the figure, when a continuous image is shot by converting RGB data for one field by YUV, since the second field is exposed during the first field transfer, the mechanical shutter is not closed. It is operating. In this case, if strong light is incident, the effect of smear cannot be removed even if high-speed sweeping is performed. Since the exposed data is transferred in the immediately following field, the time that the data is held in each pixel is short, and the influence of noise such as dark current is reduced. Therefore, the effect of high-speed sweeping cannot be expected.
For this reason, when RGB data is recorded in one field and YUV conversion is performed on the data for one field to shoot a continuous image, high-speed sweeping is not performed in each field transfer. Realizes high-speed continuous shooting and low power consumption.
[0035]
【The invention's effect】
  As mentioned above,Claim 1According to the invention,
  An interlaced transfer type solid-state imaging device in which charges for all pixels accumulated by receiving a photographed image through a plurality of color filters are transferred in a plurality of fields of three or more fields, and this solid-state imaging device In the color imaging apparatus comprising the control unit of the interlace transfer method to control,
  Data transfer corresponding to each of the plurality of fields.DeadlineRemove excess charge from the transfer path used for the data transferSurplus charge sweeping means;
  in frontData transferDeadlineBetween the surplus chargesRemovalDo notSurplus charge sweeping non-execution means;
  in frontPrior to the data transfer corresponding to each of the plurality of fields, the surplus charge sweeping is executed.meansAnd excess charge sweeping outmeansWhich of these should applyPossible setting means and,
  With
  In the continuous shooting mode in which high-speed continuous shooting is performed, the surplus charges are removed by the surplus charge sweeping execution means during the data transfer period in the first field among the plurality of fields, and the fields after the second field In the data transfer period, the surplus charge is not removed by the surplus charge sweeping non-execution means,
  In the case of the normal photographing mode, by removing the surplus charge by the surplus charge sweeping execution means in the data transfer period in all the fields of the plurality of fields,For specific fields of the plurality of fields, it may be possible to reduce the time until all the fields are read by not performing a high-speed surplus charge sweeping operation, and transfer may be performed. Even in the case where the period of the operation clock when extracting data from the path is high speed, it is possible to prevent large power consumption.
  In particular, when high-speed continuous shooting is performed, the surplus charge is swept out to remove the surplus charge during the data transfer period in at least one of the plurality of fields. Thus, in the case of continuous shooting that requires high-speed operation, the excess charge sweep-out operation can be omitted, so that the high-speed operation is ensured, and in the case of normal shooting, the conventional operation is performed. A color imaging device capable of providing high image quality can be provided.
[0036]
Further, in the execution period of the data transfer in at least one field of each of the plurality of fields, the plurality of fields are configured such that the excess charge sweeping is not performed and the excess charge is not removed. Among these, since at least one field does not require the high-speed surplus charge sweeping operation, it is possible to reduce the time until all the fields are read out, and the operation clock for extracting data from the transfer path. Even in the case where the period is high speed, it is possible to provide a color imaging apparatus capable of reliably avoiding large power consumption.
Further, among the plurality of fields, fields other than the first field are set as fields in which the surplus charge sweeping is not performed during the data transfer execution period. For one field or fields other than the first field, the high-speed surplus charge sweep-out operation can be omitted, so that it is possible to shorten the time until all the fields are read out and to transfer data from the transfer path. It is possible to provide a color imaging device that can easily avoid consuming a large amount of power even when the period of the operation clock when taking out the signal is high.
[0038]
  According to the invention of claim 2,
  An image pickup apparatus using an image pickup device in which the charge data transfer is divided into a plurality of fields of three or more fields and a plurality of color filters are provided when transferring charges of all the pixels accumulated in the image pickup device. And
  An image sensor of an interlace transfer method including a color signal composed of at least RGB or YeCyMgG in transfer data of each field for transferring the charge;
  Image sensor control means for controlling the data transfer;
  Image processing means for performing image processing with transfer data of an arbitrary number of fields transferred in the plurality of fields,
  In the imaging apparatus capable of setting whether or not the surplus charge removal operation of the transfer path is performed before data transfer to each field, the image sensor control means,
  Of the plurality of fieldsat leastonePartfieldUsing data transferred fromWhen performing image processing, in all fields used in the image processing,AboveDoes not perform excess charge removal operationConfigure asBy
  When charges for all pixels accumulated corresponding to a photographed image through a plurality of color filters are transferred in three or more fields, the data transfer period of some of the fields is transferred. Omit excess charge sweeping operation inThis enables high-speed operation and low power consumption.A color imaging device can be provided.
[0039]
  Further, according to claim 3According to the invention of
  In the drive control method of the solid-state imaging device of the interlace transfer method in which the charges for all the pixels accumulated by receiving the photographed images through the plurality of color filters are divided and transferred to a plurality of fields of three or more fields.
  Data transfer corresponding to each of the plurality of fields.DeadlineRemove excess charge from the transfer path used for the data transferExcess charge sweep execution step and previousDatatransferOf the surplus charge in the periodRemovalDo notAn excess charge sweeping non-execution step;
  in frontThe data transfer corresponding to each of the plurality of fieldsTo sendPrior to the surplus chargeSweeping out execution step and the excess charge discharging out execution stepWhich of the following should be appliedConfiguration steps that can be
  With
  In the continuous shooting mode in which high-speed continuous shooting is performed, the surplus charge is removed by the surplus charge sweeping execution step in the data transfer period in the first field, and the fields after the second field in the plurality of fields. In the data transfer period, the excess charge is not removed by the excess charge sweep-out execution step,
  In the normal photographing mode, the surplus charge is removed by the surplus charge sweeping execution step in the data transfer period in all the fields of the plurality of fields.By
  In some cases, the specific field of the plurality of fields is controlled so as not to perform a high-speed surplus charge sweeping operation, thereby shortening the time until all the fields are read out and taking out data from the transfer path. Even when the operating clock period is high, it may not be necessary to consume a large amount of power.,
  In particular, when high-speed continuous shooting is performed, the surplus charge is swept out to remove the surplus charge during the data transfer execution period in at least one of the plurality of fields. In the case of continuous shooting that requires high-speed operation, the excess charge sweep-out operation is omitted to guarantee the high-speed operation, and in the case of normal shooting, the conventional operation is performed. Therefore, it is possible to provide a drive control method for a solid-state imaging device that can provide high image quality.
[0040]
  MaAccording to the invention of claim 4,
In the drive control method of the solid-state imaging device of the interlace transfer method in which the charges for all the pixels accumulated by receiving the photographed images through the plurality of color filters are divided and transferred to a plurality of fields of three or more fields.
  A surplus charge sweeping step for removing surplus charge from a transfer path used for data transfer in a data transfer period corresponding to each of the plurality of fields; and a surplus charge not removing the surplus charge in the data transfer period Sweep-out non-execution step;
  Prior to the data transfer corresponding to each of the plurality of fields, a setting step capable of setting which of the excessive charge sweeping execution step and the excessive charge sweeping non-execution step should be applied;
  With
  Three primary color data of primary color system or complementary color system are recorded together in each of the plurality of fields, and data transferred from all the fields of the plurality of fields or a part of the plurality of fields is recorded. In the case where the image processing is performed continuously, the excess charge sweep-out non-execution step is applied in the data transfer period of all the fields to be used so that the excess charge is not removed. By
  In some cases, the specific field of the plurality of fields is controlled so as not to perform a high-speed surplus charge sweeping operation, thereby shortening the time until all the fields are read out and taking out data from the transfer path. Even when the operating clock period is high, it may not be necessary to consume a large amount of power.,While guaranteeing high-speed operation,Achieve low power consumptionIt is possible to provide a drive control method for a solid-state imaging device that can be used.
[0041]
  Further, when high-speed continuous shooting is performed, the surplus charge is swept out to remove the surplus charge during the data transfer execution period in at least one of the plurality of fields. In the case of continuous shooting that requires high-speed operation, the excess charge sweep-out operation is omitted to guarantee the high-speed operation, and in the case of normal shooting, the conventional operation is performed. Can provide a drive control method for a solid-state imaging device that can provide high image quality.
[0042]
Further, primary color data or complementary color light of three primary colors is recorded in each of the plurality of fields, and is transferred from all fields of the plurality of fields or a part of the plurality of fields. When performing continuous image processing using data, control is performed so that the surplus charge sweeping is not performed and the surplus charge is not removed during the data transfer execution period of all the fields used. By doing so, it is possible to provide a drive control method for a solid-state imaging device that enables high-speed operation and low power consumption.
[Brief description of the drawings]
FIG. 1 is a block configuration diagram illustrating a configuration of a main part of a color imaging apparatus according to an embodiment of the present invention.
FIG. 2 is a front view schematically showing an image plane of a CCD of the color imaging apparatus according to the embodiment of the present invention.
FIG. 3 is a timing chart showing an operation in the case of a three-field interlace transfer method of the color imaging apparatus according to the embodiment of the present invention.
FIG. 4 is an explanatory diagram illustrating a transfer operation of each field data of a CCD when performing three-field transfer in the color imaging apparatus according to the embodiment of the present invention.
FIG. 5 is a timing chart showing an operation in the case of capturing continuous images by YUV converting RGB data for one field in the color imaging apparatus according to the embodiment of the present invention.
FIG. 6 is a timing chart showing an operation of a three-field interlace transfer method in a conventional color imaging apparatus.
FIG. 7 is a timing chart showing an operation of a two-field interlace transfer method in a conventional color imaging apparatus.
[Explanation of symbols]
1 Imaging lens system
2 CCD
3 F / E section
4 Signal processing IC
5 SDRAM
6 Operation part
7 Shutter driver / motor driver
8 Display section
9 Memory card
10 CPU
31 CDS
32 AGC
33 A / D
41 CCD-I / F
42 Memory controller
43 YUV conversion
44 Display I / F
45 compressed blocks
51 RAW-RGB
52 YUV
53 JPEG

Claims (4)

An interlaced transfer type solid-state imaging device in which charges for all pixels accumulated by receiving a photographed image through a plurality of color filters are transferred in a plurality of fields of three or more fields, and this solid-state imaging device In the color imaging apparatus comprising the control unit of the interlace transfer method to control,
Surplus charge sweeping execution means for removing surplus charges from a transfer path used for the data transfer in a data transfer period corresponding to each of the plurality of fields;
Surplus charge sweep-out non-execution means that does not remove the surplus charge in the data transfer period;
Prior to the data transfer corresponding to each of the plurality of fields, setting means capable of setting which of the surplus charge sweep execution means and the surplus charge sweep non-execution means should be applied;
Equipped with a,
In the continuous shooting mode in which high-speed continuous shooting is performed, the surplus charges are removed by the surplus charge sweeping execution means during the data transfer period in the first field among the plurality of fields, and the fields after the second field In the data transfer period, the surplus charge is not removed by the surplus charge sweeping non-execution means,
In the normal photographing mode, the surplus charge is removed by the surplus charge sweeping-out means during the data transfer period in all of the plurality of fields . An image pickup apparatus using an image pickup device in which the charge data transfer is divided into a plurality of fields of three or more fields and a plurality of color filters are provided when transferring charges of all the pixels accumulated in the image pickup device. And
An image sensor of an interlace transfer method including a color signal composed of at least RGB or YeCyMgG in transfer data of each field for transferring the charge;
Image sensor control means for controlling the data transfer;
Image processing means for performing image processing with transfer data of an arbitrary number of fields transferred in the plurality of fields,
In the imaging apparatus capable of setting whether or not the surplus charge removal operation of the transfer path is performed before data transfer to each field, the image sensor control means,
Interlacing, characterized in that the when performing image processing by using the data transferred from at least part of the field of the plurality fields, does not perform the extra charge removing operation in all the fields used in the image processing Transfer type imaging device. In the drive control method of the solid-state imaging device of the interlace transfer method in which the charges for all the pixels accumulated by receiving the photographed images through the plurality of color filters are divided and transferred to a plurality of fields of three or more fields.
A surplus charge sweeping step for removing surplus charge from a transfer path used for data transfer in a data transfer period corresponding to each of the plurality of fields; and a surplus charge not removing the surplus charge in the data transfer period Sweep-out non-execution step;
Prior to the data transfer corresponding to each of the plurality of fields, a setting step capable of setting which of the excessive charge sweeping execution step and the excessive charge sweeping non-execution step should be applied;
Equipped with a,
In the continuous shooting mode in which high-speed continuous shooting is performed, the surplus charge is removed by the surplus charge sweeping execution step in the data transfer period in the first field, and the fields after the second field in the plurality of fields. In the data transfer period, the excess charge is not removed by the excess charge sweep-out execution step,
In the normal photographing mode, the surplus charge is removed by the surplus charge sweeping execution step during the data transfer period in all the fields of the plurality of fields . In the drive control method of the solid-state imaging device of the interlace transfer method in which the charges for all the pixels accumulated by receiving the photographed images through the plurality of color filters are divided and transferred to a plurality of fields of three or more fields.
A surplus charge sweeping step for removing surplus charge from a transfer path used for data transfer in a data transfer period corresponding to each of the plurality of fields; and a surplus charge not removing the surplus charge in the data transfer period Sweep-out non-execution step;
Prior to the data transfer corresponding to each of the plurality of fields, a setting step capable of setting which of the excessive charge sweeping execution step and the excessive charge sweeping non-execution step should be applied;
With
Three primary color data of primary color system or complementary color system are recorded together in each of the plurality of fields, and data transferred from all the fields of the plurality of fields or a part of the plurality of fields is recorded. In the case where the image processing is performed continuously, the excess charge sweep-out non-execution step is applied in the data transfer period of all the fields to be used so that the excess charge is not removed. A drive control method for a solid-state imaging device.

Images