JP2010050526A - Electronic camera - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problem that it is difficult for the conventional electronic camera that performs consecutive photographing to correspond to various consecutive photographing speeds. <P>SOLUTION: This invention relates to an electronic camera provided with an imaging element for reading a plurality of fields by dividing the fields, which includes a timing generating part for giving timing that corresponds to the number of fields for reading an image signal from the imaging element, a consecutive photographing mode selecting part for selecting a consecutive photographing mode, and a control part for instructing the timing generating part about the number of fields for reading the image signal from the imaging element in accordance with the consecutive photographing mode selected by the consecutive photographing mode selecting part. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an electronic camera having a continuous shooting function.

2. Description of the Related Art In recent years, solid-state imaging devices used in electronic cameras have been rapidly increasing in pixel count due to miniaturization of semiconductor processes. On the other hand, the need for continuous shooting for continuously capturing a plurality of images has increased, and a technique for performing high-speed continuous shooting has been studied (for example, see Patent Document 1).
JP 2003-224858 A

  In general, in order to read out high-pixel image data from a solid-state imaging device quickly, it is necessary to increase the driving frequency, but on the other hand, since the power consumption of electronic cameras is also required, the driving frequency cannot be increased so much. There is a problem. As a result, in the frame mode in which all the pixels are read from the solid-state imaging device, the frame rate of the continuously shot image is slowed down. In addition, since an image with high pixels takes time not only for reading from pixels but also for image processing such as color interpolation processing of the read image, for example, it takes several hundred msec or more to shoot one image. Sometimes.

  On the other hand, there are shooting modes with a high frame rate, such as a preview mode and moving image shooting, but the resolution of the image to be shot is fixed, and it is difficult to cope with various continuous shooting speeds. In these shooting modes, since shooting is performed with an electronic shutter, a problem such as smear occurs, which is not suitable for high-quality still image shooting.

  An object of the present invention is to provide an electronic camera that can cope with various continuous shooting speeds.

  An electronic camera according to the present invention is an electronic camera provided with an imaging device that performs divided readout of a plurality of fields, and includes a timing generation unit that gives a timing according to the number of fields from which image signals are read from the imaging device, and a continuous shooting mode And a control unit that instructs the timing generation unit the number of fields from which the image signal is read out from the image sensor according to the continuous shooting mode selected by the continuous shooting mode selection unit. It is characterized by that.

  More preferably, as the continuous shooting mode selected by the continuous shooting mode selection unit, the resolution of an image to be captured is selected, and the control unit is responsive to the resolution selected by the continuous shooting mode selection unit. The number of fields from which the image signal is read from the image sensor is determined and the timing generation unit is instructed.

  More preferably, the continuous shooting frame rate is selected as the continuous shooting mode selected by the continuous shooting mode selection unit, and the control unit sets the frame rate selected by the continuous shooting mode selection unit. Accordingly, the number of fields from which the image signal is read from the image sensor is determined and the timing generation unit is instructed.

  According to the present invention, in an electronic camera having a continuous shooting function, it is possible to select a continuous shooting mode corresponding to various continuous shooting speeds.

  Hereinafter, an embodiment of an electronic camera 101 according to the present invention will be described in detail with reference to the drawings.

(First embodiment)
[Configuration of Electronic Camera 101]
FIG. 1 is a block diagram illustrating a configuration of an electronic camera 101 according to the present embodiment. Note that the electronic camera 101 according to the present embodiment has a continuous shooting mode in which a plurality of images are continuously captured while the release button is pressed.

  In FIG. 1, an electronic camera 101 includes a lens optical system 102, a mechanical shutter 103, a CCD (CCD-type imaging device) 104, an AFETG (analog front-end timing generator) 105, a control unit 106, a memory 107, and the like. , An LCD (Liquid Crystal Display) 108, an operation unit 109, a lens driving unit 110, and a battery 111.

  The AFET G 105 includes a TG (timing generator) 151, a V-driver (vertical drive unit) 152, and an AFE (analog front end) 153.

  The control unit 106 is configured around a CPU (central processing unit) that operates according to a program stored in advance, and controls each unit of the electronic camera 101. For example, an instruction to read an image signal of a predetermined field of the CCD 104 is given to the TG 151 of the AFETG 105, and the image signal of the predetermined field read from the CCD 104 is input to the control unit 106 via the AFE 153 and stored in the memory 107. Incidentally, the CCD 104 is a CCD type image pickup device capable of division reading in a plurality of fields.

  The TG 151 gives the readout timing of the image signal directly to the CCD 104 and via the V-driver 152. In particular, the timing for reading out the image signal of the field designated by the control unit 106 from the CCD 104 is given.

  Here, the pixel configuration of the CCD 104 will be described. FIG. 2 is an explanatory diagram depicting a part of the pixels of the CCD 104 having a Bayer array color filter. In FIG. 2, G (green) and B (blue) color filters are alternately arranged in the column direction in odd rows, and R (red) and G (green) color filters are alternately arranged in the column direction in even rows. Is arranged. Note that the CCD 104 in the present embodiment is an image sensor that can be read out in five fields. For example, when the field 1 (1st) is read, the TG 151 gives the timing for reading the image signal every five lines, such as the first line, the sixth line, the eleventh line,. When the field 2 (2nd) is read, the timing for reading the image signal is given every five lines, such as the second line, the seventh line, the twelfth line, and so on. Similarly, when reading field 3 (3rd), every 5th row from the 3rd row, when reading field 4 (4th), every 5th row from the 4th row, and when reading field 5 (5th), 5 rows Timings for reading out image signals are given every five lines from the eyes.

  Further, the TG 151 gives a timing for reading not only one field but also a plurality of fields in an arbitrary combination in accordance with an instruction from the control unit 106. For example, two fields, field 1 and field 2, can be read. In this case, the TG 151 gives the timing for reading the image signal from the CCD 104 as in the first and second rows, the sixth and seventh rows, the eleventh and twelfth rows, and so on. Similarly, when reading three fields of field 1, field 2, and field 3, the TG 151 reads lines 1, 2, 3, 6, 7, 8, 11, The timing to read out the image signal from the CCD 104 is given as in the 12th and 13th lines. Similarly, when reading four fields of field 1, field 2, field 3, and field 4, the TG 151 reads the 1st line, 2nd line, 3rd line, 4th line, 6th line, 7th line, and 8th line. A timing is given to read out image signals from the CCD 104 for rows other than multiples of 5 such as the fifth row, the tenth row, etc. When reading out five fields (all fields) from field 1 to field 5, the TG 151 gives timing for reading out image signals of all rows from the CCD 104.

  As described above, the TG 151 gives the CCD 104 the timing for reading any one field or any plurality of fields designated by the control unit 106. A detailed timing chart will be described later in detail.

  In FIG. 1, the AFE 153 performs noise removal and amplification of an analog image signal read from the CCD 104, then A / D converts it to digital image data, and outputs the digital image data to the control unit 106.

  A user of the electronic camera 101 uses the electronic camera 101 by operating a power button, a release button, a zoom button, and the like of the operation unit 109. In particular, the present embodiment has a function of selecting a continuous shooting mode, and the operation unit 109 is provided with a dedicated continuous shooting mode selection button. The operation unit 109 is also provided with a cursor button, an OK button, and the like, and a detailed shooting mode can be set by selecting a menu screen displayed on the LCD 108. Therefore, the operation unit 109 may be selected on the menu screen without providing a dedicated continuous shooting mode selection button.

  The battery 111 is input to the control unit 106 and starts supplying power to each unit of the electronic camera 101 when the power button of the operation unit 109 is turned on. On the contrary, when the power button of the operation unit 109 is turned off, the power supply to each unit of the electronic camera 101 is stopped.

  The LCD 108 displays a menu screen output from the control unit 106 and an image of image data read out from the memory 107 by the control unit 106.

  The lens driving unit 110 moves the focus lens position and the zoom lens position of the lens optical system 102 based on a command from the control unit 106. For example, the control unit 106 obtains a focus position from image data input from the CCD 104 via the AFE 153 and instructs the lens driving unit 110 to move the focus lens position of the lens optical system 102 to adjust the focus. Alternatively, the control unit 106 instructs the lens driving unit 110 to move the zoom lens position of the lens optical system 102 according to the operation of the zoom button of the operation unit 109.

  The mechanical shutter 103 includes a shutter driving unit, and is opened and closed according to a command from the control unit 106.

The memory 107 stores image data captured by the CCD 104 and also stores parameters necessary for the operation of the control unit 106. The memory 107 may be a storage medium such as a memory card that can be attached to the electronic camera 101.
[Operation of Electronic Camera 101]
Next, the operation of the electronic camera 101 will be described. As described above, the electronic camera 101 according to the present embodiment can select the continuous shooting mode from high speed to low speed by the continuous shooting mode selection button of the operation unit 109. For example, when the CCD 104 is an image sensor that can be divided and read in five fields, as shown in FIG. 3, the control unit 106 selects the continuous shooting mode selected by the continuous shooting mode selection button. The number of fields read from the CCD 104 is instructed to the TG 151.

  FIG. 3 is an explanatory diagram showing the relationship between the continuous shooting mode and the number of fields. In FIG. 3, when the continuous shooting mode R1 is selected by the continuous shooting mode selection button, the number of fields read from the CCD 104 is only one field. In this case, it is assumed that which of the five types of fields described in FIG. When the continuous shooting mode R2 is selected by the continuous shooting mode selection button, the number of fields read from the CCD 104 is two fields. In this case as well, it is assumed that which two fields are read out of the five types of fields described in FIG. Similarly, when the continuous shooting mode R3 is selected by the continuous shooting mode selection button, three fields are displayed. When the continuous shooting mode R4 is selected, four fields are displayed. When the continuous shooting mode R5 is selected, five fields are displayed. Each field is read from the CCD 104. In these cases, it is assumed that which field combination is selected and read out from the five types of fields described in FIG. Further, it is assumed that the memory 107 stores in advance a table indicating correspondence between continuous shooting modes and the number of fields, combinations of field numbers to be read out, and the like.

  As described above, the electronic camera 101 according to the present embodiment can perform continuous shooting from high speed to low speed according to the continuous shooting mode selected by the continuous shooting mode selection button of the operation unit 109. Next, operations in each continuous shooting mode will be described in order.

(Operation in continuous shooting mode R5 (when reading all fields))
First, an operation when the continuous shooting mode R5 of FIG. 3 is selected will be described. FIG. 4 is a timing chart when all fields from the first field to the fifth field (all pixels of the CCD 104) are divided into five fields and read from the CCD 104. In FIG. 4, VD is a frame synchronization signal (a signal for giving a timing for reading out an image signal for one screen), φV is a vertical drive signal (a timing for reading from a photodiode to a vertical signal line, and a timing for reading from a vertical signal line to an output circuit) The signals that give it respectively).

  FIG. 4 shows the opening / closing timings of the electronic shutter and the mechanical shutter 103 in accordance with the timing signals VD and φV. The electronic shutter is an electric shutter that repeats exposure while the mechanical shutter 103 is opened and the charge of the photodiode of the CCD 104 is appropriately discharged. For example, in FIG. 4, when the electronic shutter opening / closing signal is closed (when it is at a high level), the timing at which the charge accumulated in the photodiode of the CCD 104 is discharged is shown.

  In FIG. 4, a preview image is displayed on the LCD 108 during the period up to the timing A <b> 1, and the photographer is waiting for a photo opportunity while looking at the screen of the LCD 108. During the period after timing A1, the release button is pressed and continuous shooting is being performed. Note that the continuous shooting mode in this embodiment is a mode in which a plurality of images are continuously captured while the release button is pressed down, but is set in advance by a single release button operation. The mode may be such that a specified number of images are captured.

  Here, the photographer waits for a photo opportunity while viewing the preview image displayed on the LCD 108, and presses the release button to start continuous shooting. When continuous shooting is started, a pulse Pe of the electronic shutter is output from the TG 151, and the electronic shutter is temporarily closed. As a result, the charge of the photodiode of each pixel is discharged, and exposure of the first image in continuous shooting is started from the falling edge of the pulse Pe of the electronic shutter. Then, charges corresponding to the subject light are accumulated in the photodiodes of all the pixels of the CCD 104 during the VD exposure period t1. Thereafter, at timing A2, the mechanical shutter 103 is closed and the exposure is completed.

  The φV pulse Pd1 after completion of exposure is a pulse train (a plurality of pulses corresponding to the number of rows constituting each field) for sweeping out unnecessary charges left in the vertical signal line. The vertical signal line is provided for each column, but the charge when the charge of the previous frame is read is left in the vertical signal line. Therefore, unnecessary charges remaining in the vertical signal line are removed before reading the first field. Similarly, before reading the second field, the pulse Pd2 is read before the third field, the pulse Pd4 is read before the fourth field, the pulse Pd5 is read before the fifth field, and the vertical signal is read before the fifth field. This is a pulse train for sweeping out unnecessary charges left in the line. In the present embodiment, the pulse train means a series of signals composed of a plurality of pulses.

  A pulse Pa1 of φV gives the timing for transferring the charge accumulated in the photodiodes of each pixel corresponding to the row of the first field to the vertical signal line provided for each column. Similarly, the pulse Pa2 is in the second field row, the pulse Pa3 is in the third field row, the pulse Pa4 is in the fourth field row, and the pulse Pa5 is in the fifth field row. Timing is given to transfer the electric charge accumulated in the diode to the vertical signal line provided for each column.

  Further, the φV pulse Ps1 is a pulse train for forming charges transferred from the photodiodes of the pixels in the first field to the vertical signal line from the CCD 104 as image signals for one field for each row (which constitutes each field). A plurality of pulses corresponding to the number of rows). Similarly, the pulse Ps2 is in the second field row, the pulse Ps3 is in the third field row, the pulse Ps4 is in the fourth field row, and the pulse Ps5 is in the fifth field row. This is a pulse train for outputting the charge transferred from the diode to the vertical signal line from the CCD 104 as an image signal for one field for each row.

  As described above, the image signal of the first field is read from the CCD 104 in the readout period t2 of the first field, and the image signal of the second field is read from the CCD 104 in the readout period t3 of the second field. Similarly, the image signal of the third field is read in the readout period t4 of the third field, the image signal of the fourth field is read out in the readout period t5 of the fourth field, and the image signal of the fifth field is read out in the readout period t6 of the fifth field. , Respectively, from the CCD 104.

  In the period from timing A2 to timing A3, the first image of continuous shooting is read out in five fields from the first field to the fifth field with the mechanical shutter 103 closed.

  Similar to the first image in the continuous shooting from the timing A1 to the timing A3, the second image in the continuous shooting is taken after the timing A3. Even when three or more continuous shootings are performed, the shooting is performed at the same timing as the first image from timing A1 to timing A3.

(Operation in continuous shooting mode R1 (when reading only one field))
Next, the operation when the continuous shooting mode R1 of FIG. 3 is selected will be described. FIG. 5 is a timing chart in the case where one field of only the first field is read from the CCD 104. FIG. 5 illustrates timing signals VD and φV output from the TG 151 and V-driver 152 to the CCD 104 and the opening / closing timings of the electronic shutter and the mechanical shutter 103, as in FIG. The same reference numerals as those in FIG. 4 denote the same elements.

  In FIG. 5, when the release button is pressed during the preview period up to timing A1, continuous shooting processing starts from timing A1. First, the charge of the photodiode of each pixel is discharged by the pulse Pe of the electronic shutter, and the exposure of the first image in the continuous shooting is started from the falling edge of the pulse Pe of the electronic shutter. During the VD exposure period t1, charges corresponding to the subject light are accumulated in the photodiode of the CCD 104, the mechanical shutter 103 is closed at timing A2, and the exposure of the first image is completed. Unnecessary charges left in the vertical signal line are swept out by the pulse Pd1 after the exposure is completed, and the charges accumulated in the photodiodes of the respective pixels corresponding to the first field row are used as the vertical signal line in the next pulse Pa1. Forward. Further, the charge transferred from the photodiode of each pixel in the first field to the vertical signal line at the next pulse Ps1 is output from the CCD 104 as an image signal for one field for each row. The mechanical shutter 103 is in an open state during a period from timing A1 to timing A2, and is in a closed state during a period from timing A2 to timing A3 '.

  In this manner, the shooting of the first field image, that is, the first image of the continuous shooting is completed at the timing A3 '.

  In the case of all-field reading described with reference to FIG. 4, the reading of the second field image is performed when reading of the image of the first field is completed, but in the continuous shooting mode R1, the reading of the image of the first field is performed. When finished, shooting of the second image in continuous shooting is started. In FIG. 5, the period from timing A3 'to timing A5' is the shooting period of the second image in continuous shooting. Here, the second image of the continuous shooting is taken at the same timing as the first image of the continuous shooting. For example, the timing A3 'corresponds to the timing A1 of the first image, and the pulse Pe' corresponds to the pulse Pe. Similarly, the exposure period t1 ′ is the exposure period t1, the exposure end timing A4 ′ is the timing A2, the readout period t2 ′ is the readout period t2, the pulse Pa1 ′ is the pulse Pa1, and the second image has been captured. The timing A5 ′ corresponds to the shooting end timing A3 ′ of the first image. The mechanical shutter 103 is in an open state from timing A3 'to timing A4', and is closed from timing A4 'to timing A5'. In addition, since the charges accumulated in the photodiodes of the respective pixels corresponding to the first field row are transferred to the vertical signal line by the pulse Pa1 ′, the image read out in the readout period t2 ′ is the first one in continuous shooting. This is the first field image as in the case of the image.

  In this way, the shooting of the second image in the continuous shooting is completed. When three or more continuous shots are taken, the third and subsequent images are taken at the same timing, and the images in the first field are also read out for these images. The above is the operation in the continuous shooting mode R1 (when reading only one field).

(Operation in continuous shooting mode R3 (when reading three fields))
Next, an operation when the continuous shooting mode R3 of FIG. 6 is selected will be described. FIG. 6 is a timing chart in the case where three fields of the first field, the third field, and the fifth field are read out from the CCD 104. FIG. 6 illustrates timing signals VD and φV output from the TG 151 and the V-driver 152 to the CCD 104 and the opening / closing timings of the electronic shutter and the mechanical shutter 103, as in FIG. The same reference numerals as those in FIG. 4 denote the same elements.

  In FIG. 6, when the release button is pressed during the preview period up to timing A1, continuous shooting processing starts from timing A1. First, the charge of the photodiode of each pixel is discharged by the pulse Pe of the electronic shutter, and the exposure of the first image in the continuous shooting is started from the falling edge of the pulse Pe of the electronic shutter. During the VD exposure period t1, charges corresponding to the subject light are accumulated in the photodiode of the CCD 104, the mechanical shutter 103 is closed at timing A2, and the exposure of the first image is completed. Unnecessary charges left in the vertical signal line are swept out by the pulse Pd1 after the exposure is completed, and the charges accumulated in the photodiodes of the respective pixels corresponding to the first field row are used as the vertical signal line in the next pulse Pa1. Forward. Further, the charge transferred from the photodiode of each pixel in the first field to the vertical signal line at the next pulse Ps1 is output from the CCD 104 as an image signal for one field (image in the first field) for each row. The mechanical shutter 103 is in an open state during a period from timing A1 to timing A2, and is in a closed state during a period from timing A2 to timing A3 ''.

  Similarly, unnecessary charges left in the vertical signal line are swept out by the pulse Pd3 ′, and charges accumulated in the photodiodes of the respective pixels corresponding to the third field row are swept by the next pulse Pa3 ′. Forward to. Further, the charge transferred from the photodiode of each pixel in the third field to the vertical signal line at the next pulse Ps3 'is output from the CCD 104 as an image signal for one field (image in the third field) for each row.

  Furthermore, unnecessary charges remaining in the vertical signal line are swept out by the pulse Pd5 ′, and charges accumulated in the photodiodes of the respective pixels corresponding to the fifth field row are transferred to the vertical signal line by the next pulse Pa5 ′. Forward. Further, the charges transferred from the photodiode of each pixel in the fifth field to the vertical signal line at the next pulse Ps5 'are output from the CCD 104 as an image signal for one field (image in the fifth field) for each row.

  The series of operations described above ends at timing A3 ″, and the imaging of the three fields of the first field, the third field, and the fifth field, i.e., the first image of the continuous shooting, is completed.

  Similarly, the shooting of the second image of the continuous shooting is started after timing A3 ″, the electric charge of the photodiode of each pixel is discharged by the pulse Pe ″ of the electronic shutter, and the falling of the pulse Pe ″. The exposure of the second image in continuous shooting is started. Thereafter, the second image of the continuous shooting is shot at the same timing operation as the shooting of the first image of the continuous shooting described above. At the timing A4 ″, the exposure of the second image of the continuous shooting is finished, the images of the first field, the third field, and the fifth field are read out, and at the timing A5 ″, two images of the continuous shooting are taken. Shooting of the eye image ends. When three or more continuous shots are taken, the third and subsequent images are taken at the same timing, but these images also have three fields, the first field, the third field, and the fifth field. Images are read out.

  As described above, from the CCD 104 in the three continuous shooting modes R5 (when reading all fields), the continuous shooting mode R1 (when reading only one field), and the continuous shooting mode R3 (when reading three fields). The image signal read operation has been described. In the continuous shooting mode R2 (when reading only two fields) and the continuous shooting mode R4 (when reading four fields), the number of fields read after exposure only increases or decreases. The timing operation described with reference to FIGS. 5 and 6 is basically the same.

  Here, the relationship between the number of fields for reading image signals from the CCD 104 and the frame rate for continuous shooting will be described. FIG. 7 is an explanatory diagram showing a readout time and a frame rate of continuous shooting in the case of the CCD 104 having a reference clock for reading out an image signal of 36 MHz (about 0.28 μsec per clock) and one field of 551 rows. is there. In the example of FIG. 7, 5136 clocks (about 0.00014 sec) are required to read out an image signal for one row (1 HD), and 0.00014 sec × 551 rows (about 0 row) to read out an image signal for one field. .07786 seconds) is required. Note that the frame rate varies depending on the frequency of the reference clock and the number of pixels of the CCD 104.

  In FIG. 7, in the continuous shooting mode R1, since one image of continuous shooting is composed of one field, the number of fields read from the CCD 104 is 1, and the reading time is about 0.07861 sec. Accordingly, if the frame rate of continuous shooting is regarded as the reciprocal of the readout time, a frame rate of about 12.72 fps can be obtained. Note that the actual operation includes processing other than readout, so the frame rate for continuous shooting is not simply the reciprocal of the readout time, but the processing time other than readout is shorter than the readout time. The shooting frame rate may be regarded as the reciprocal of the readout time.

  Similarly, in the continuous shooting mode R2, since one continuous shooting image is composed of two fields, the readout time from the CCD 104 is twice that of the continuous shooting mode R1 (about 0.15722 sec). ). Therefore, the frame rate of continuous shooting is ½ of the continuous shooting mode R1 (about 6.36 fps).

  In the continuous shooting mode R3, since one image of continuous shooting is composed of three fields, the readout time from the CCD 104 is three times as long as the continuous shooting mode R1 (about 0.23583 sec). Therefore, the frame rate of continuous shooting is 1/3 of the continuous shooting mode R1 (about 4.24 fps).

  In the continuous shooting mode R4, since one image of continuous shooting is composed of four fields, the readout time from the CCD 104 is four times that of the continuous shooting mode R1 (about 0.31444 sec). Therefore, the frame rate of continuous shooting is ¼ that of the continuous shooting mode R1 (about 3.18 fps).

  In the continuous shooting mode R5, since one image of continuous shooting is composed of five fields, the readout time from the CCD 104 is five times that of the continuous shooting mode R1 (about 0.39305 sec). Therefore, the frame rate of continuous shooting is 1/5 of the continuous shooting mode R1 (about 2.54 fps).

  In FIG. 7, the resolution is inversely proportional to the frame rate of continuous shooting, and the resolution increases as the frame rate of continuous shooting decreases, and the resolution decreases as the frame rate of continuous shooting increases. In other words, the resolution is proportional to the number of fields read from the CCD 104. If the number of fields is doubled, the resolution in the vertical direction is doubled. If the number of fields is tripled, the resolution in the vertical direction is tripled. .

  Thus, the number of fields read from the CCD 104 can be determined according to the continuous shooting mode selected by the continuous shooting mode selection button of the operation unit 109. In this embodiment, the continuous shooting mode selection button can select five continuous shooting modes from the continuous shooting mode R1 to the continuous shooting mode R5. However, according to the number of fields that can be divided and read by the CCD 104. The number of continuous shooting mode options may be increased or decreased. For example, in the case where the CCD 104 is an image sensor that can be divided into eight, eight continuous shooting modes from the continuous shooting mode R1 to the continuous shooting mode R8 may be provided, and two fields are used without using all eight dividing functions. It is also possible to provide four continuous shooting modes from the continuous shooting mode R1 to the continuous shooting mode R4 by using it as an image pickup device capable of reading in four divisions. Alternatively, among the eight fields divided into eight, the continuous shooting mode R1 is one field, the continuous shooting mode R2 is three fields, the continuous shooting mode R3 is five fields, and the continuous shooting mode R4 is seven fields. The copy mode R5 may be eight fields (all pixels).

  The photographer may select a frame rate for continuous shooting instead of selecting a continuous shooting mode name (R1 to R5). In this case, a continuous shooting frame rate selection button is provided instead of the continuous shooting mode selection button, and a desired frame rate is selected from, for example, three frame rates of 10 fps, 5 fps, and 2 fps. It should be noted that a desired frame rate may be set with a numerical value from 1 fps to 10 fps.

  Alternatively, the photographer may select the resolution of the continuous shooting image instead of selecting the continuous shooting mode name (R1 to R5). In this case, a continuous shooting resolution selection button is provided instead of the continuous shooting mode selection button, and a desired resolution is selected from, for example, three types of resolutions of high resolution, medium resolution, and low resolution. Alternatively, 160 × 120 pixels, 320 × 240 pixels, 640 × 480 pixels, 1280 × 1024 pixels, 3800 × 2600 pixels, and the like may be set as numerical values.

  In any case, as described with reference to FIG. 7, the control unit 106 according to the continuous shooting mode (continuous shooting mode name, continuous frame rate, continuous shooting resolution, etc.) selected by the photographer using the operation unit 109. Obtains the number of fields to be read from the CCD 104 and instructs the TG 151 of the AFET G 105 to read the field from the CCD 104. Note that it is assumed that the field to be read out is stored in advance in the memory 107 according to the number of fields, and the control unit 106 refers to the memory 107 and determines a field to be read from the CCD 104.

  As described above, the electronic camera 101 according to the present embodiment can flexibly cope with various continuous shooting speeds selected by the photographer. In particular, the electronic camera 101 does not need to increase the drive frequency for reading an image signal from the CCD 104, and does not increase power consumption. Further, since the electronic camera 101 performs continuous shooting using the mechanical shutter 103, there is no problem such as smear that occurs when continuous shooting is performed using the electronic shutter, and high-quality still images can be continuously shot. .

1 is a block diagram of an electronic camera 101 according to a first embodiment. 3 is an explanatory diagram illustrating a part of a pixel of a CCD 104. FIG. It is explanatory drawing which showed the relationship between continuous shooting mode and the number of fields. It is a timing chart in the case of continuous shooting mode R5. It is a timing chart in the case of continuous shooting mode R1. It is a timing chart in the case of continuous shooting mode R3. It is explanatory drawing which showed the relationship between the readout time of CCD104, the frame rate of continuous shooting, and the resolution.

Explanation of symbols

DESCRIPTION OF SYMBOLS 101 ... Electronic camera 102 ... Lens optical system 103 ... Mechanical shutter 104 ... CCD
105 ... AFETG 106 ... Control unit 107 ... Memory 108 ... LCD
109: Operation unit 110 ... Lens drive unit 111 ... Battery 151 ... TG
152 ... V-driver 153 ... AFE

Claims (3)

An electronic camera equipped with an image sensor that performs divided readout of a plurality of fields,
A timing generator for providing timing according to the number of fields for reading image signals from the image sensor;
A continuous shooting mode selection section for selecting a continuous shooting mode;
An electronic camera comprising: a control unit that instructs the timing generation unit the number of fields from which the image signal is read out from the image sensor according to the continuous shooting mode selected by the continuous shooting mode selection unit. The electronic camera according to claim 1,
As the continuous shooting mode selected by the continuous shooting mode selection unit, the resolution of the image to be taken is selected,
The electronic camera according to claim 1, wherein the control unit determines the number of fields from which the image signal is read from the image sensor according to the resolution selected by the continuous shooting mode selection unit, and instructs the timing generation unit. The electronic camera according to claim 1,
As the continuous shooting mode selected by the continuous shooting mode selection unit, the frame rate of continuous shooting is selected,
The electronic camera according to claim 1, wherein the control unit determines the number of fields from which the image signal is read from the image sensor according to the frame rate selected by the continuous shooting mode selection unit, and instructs the timing generation unit.

Images