JP4262298B2 - Imaging device - Google Patents

Description

  The present invention relates to an imaging apparatus capable of shooting a moving image and a still image, and more particularly to control when shooting a still image.

  Conventionally, there are video cameras having a still image shooting mode. In still image shooting of this conventional video camera, in order to increase image information on one screen, image data for one frame of a moving image is repeatedly recorded on a video tape for storing moving images for a predetermined time, or the influence of camera shake. When a shooting mode for shooting a still image is set in order to reduce this, the so-called electronic shutter that controls the storage time of the CCD, which is an image sensor, shortens the CCD storage time.

On the other hand, an image is taken using a CCD, and the obtained image signal is signal-processed and converted into image information, and the result is stored in a memory card comprising a flash memory, a floppy (registered trademark) disk, or a recording means comprising a hard disk. Various proposals of so-called digital cameras for recording are provided, and some of them can shoot and record moving images.
Japanese Patent Laid-Open No. 05-041843 Japanese Patent Laid-Open No. 04-369976 Japanese Unexamined Patent Publication No. 63-0457979 JP-A-63-047711 Japanese Patent Laid-Open No. 03-214133 Japanese Patent Laid-Open No. 05-056337 JP 09-023371 A JP 09-083945 A

Meanwhile, a video camera, and video in a digital camera, when taking a still image, the features of each shooting, the optimum conditions for shake correction will be different. More specifically, in exposure adjustment, in the case of a moving image, rather than using an electronic shutter to reduce the image shake, the amount of shake accumulated in the CCD after being exposed for a predetermined period determined by the video synchronization signal. In contrast, a continuous and smooth moving image can be obtained in contrast to a still image, while it is desirable to reduce the shake of the image using an electronic shutter or the like for a still image .

  As described above, in the case of shooting a moving image and the case of shooting a still image, although there is a difference in desirable setting for exposure adjustment when shooting, in a conventional video camera or a so-called digital camera, Because shooting conditions were selected only under conditions suitable for the above, there was a problem that when shooting a still image while shooting a movie, either the movie or the still image would not be a good image .

  The present invention has been made under such circumstances, and it is an object of the present invention to provide an imaging apparatus capable of shooting a moving image and a still image without causing unnaturalness when shooting a still image. Is.

  In order to achieve the above object, in the present invention, the imaging apparatus is configured as described in the following (1) to (3).

(1) a moving image and an imaging device capable of still image photographing, the optical camera shake correction means, and control means for controlling the frequency characteristic of the operation of the optical camera shake correction means for detecting the vibration, for still image shooting and a release means having a plurality of stages of switches, the control means, in response to operation of the first stage of the switches of the plurality of stages by the operation of said release means, said optical shake correction The optical image stabilization unit is configured to switch the frequency characteristic of the operation to a higher frequency side than a cutoff frequency at the time of moving image shooting, and to switch the cutoff frequency to a lower frequency side according to the operation of the second stage switch. An image pickup apparatus for controlling the frequency characteristic of the operation so as to be different from that during moving image shooting.

  (3) Release means having a plurality of stages of switches for still image shooting is provided, and the control means is responsive to the operation of the first stage switch among the plurality of stages of switches by operation of the release means. The image pickup apparatus according to (2), wherein the optical camera shake correction means is controlled to return to the vicinity of the optical neutral position.

  According to the present invention, it is possible to provide optimum shooting conditions for both shooting a moving image and shooting a still image. Further, even if still image shooting is performed during moving image shooting, each shooting can be performed without the unnaturalness associated with still image shooting.

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

  FIG. 1 is a principal block diagram of the “video camera” according to the first embodiment. FIG. 2 is a flowchart for explaining photographing mode switching according to the first embodiment.

  In FIG. 1, 1 is a photographing lens, 2 is a CCD, 3 is a video signal processing circuit, 4 is an image signal recording means including a video deck, 5 is a microcomputer, 6 is a focus drive circuit, 7 is a switch button, and 8 is a first button. 1 is a first pull-up resistor, SW1 is a first-stage switch, 10 is a second spring, 11 is a second pull-up resistor, and SW2 is a second-stage switch. The button 7, the first spring 8, the first pull-up resistor 9, the first-stage switch SW1, the second spring 10, the second pull-up resistor 11, and the switch SW2 constitute a two-stage switch. ing.

  The taking lens 1 is a so-called rear focus type zoom lens, and includes a first fixed lens 1b, a variable magnification lens 1c as a first moving lens, a second fixed lens 1d, and a second movement as a focus lens. It has a photographic optical lens composed of a lens 1e, and also has an actuator for driving the variable magnification lens 1c and the focus lens 1e, a sensor for detecting the position of the moving lens, and an aperture 1f that also functions as a shutter. . Here, the actuator and the sensor are not directly related to the contents of the present invention, and thus are not shown in FIG.

  A CCD substrate 2a to which the CCD 2 is fixed is fixed to the photographing lens 1 so that the CCD 2 as an imaging element is positioned at the focal position.

  The video signal processing circuit 3 has a first input terminal 3a, a second input terminal 3b, a first output terminal 3c, and a second output terminal 3d. The first input terminal 3a is an output of the CCD 2. The second input terminal 3 b is electrically connected to the first output terminal 5 a of the microcomputer 5, and the first output terminal 3 c is connected to the input terminal 4 a of the image signal recording means 4. The second output terminal 3 d is electrically connected to the first input terminal 5 b of the microcomputer 5.

  The video signal processing circuit 3 sequentially reads out the image signal stored in the CCD 2 through the first input terminal 3a, and outputs it to the image signal recording means 4 as a video signal through the first output terminal 3c. The focus information in the pixel range (ranging area) designated by the microcomputer 5 via the second input terminal 3b is output to the microcomputer 5 via the second output terminal 3d.

  The image signal recording means 4 includes, for example, a video deck, a video tape, a memory card slot, and a memory card, and has an input terminal 4a and an output terminal (not shown). The input terminal 4a of the image signal recording means 4 is electrically connected to the first output terminal 3c of the video signal processing circuit 3, and the image signal recording means 4 records the video signal input to the input terminal 4a.

  The microcomputer 5 is a known microcomputer, and has a first output terminal 5a, a first input terminal 5b, a second output terminal 5c, and second and third input terminals 5d and 5e.

  The first output terminal 5 a of the microcomputer 5 is electrically connected to the second input terminal 3 b of the video signal processing circuit 3, and the first input terminal 5 b is the second input terminal of the video signal processing circuit 3. The second output terminal 5c is electrically connected to the first input terminal 6a of the focus driving circuit 6, and the second input terminal 5d is electrically connected to the first-stage electric terminal 3d. The third input terminal 5e is electrically connected to the switch SW1, and the third input terminal 5e is electrically connected to the second-stage electrical switch SW2.

  The microcomputer 5 designates the size of the distance measuring area to the video signal processing circuit 3 via the first output terminal 5a according to the state of the second and third input terminals 5d and 5e, and the first input. Focus information within the distance measurement area is input from the video signal processing circuit 3 via the terminal 5b, and a focus drive command is output from the second output terminal 5c to the focus drive circuit 6 based on the information, thereby driving the focus. Focusing is performed by the circuit 6 driving a motor (not shown) that drives the focus lens 1e.

  The focus drive circuit 6 is a well-known motor drive circuit, and has an input terminal 6a and an output terminal 6b. The input terminal is electrically connected to the second output terminal 5c of the microcomputer 5, and the output terminal 6b is It is connected to a motor (not shown) that drives the focus compensator 1e.

  The focus drive circuit 6 drives a motor (not shown) according to a drive command from the microcomputer 5 input to the input terminal, and moves the focus compensator 1e in the optical axis direction.

  The switch button 7, the first and second springs 8 and 10, the first-stage switch SW1, and the second-stage switch SW2 form a release switch for taking a two-stage still image. One end of the first-stage and second-stage switches SW1 and SW2 is grounded, and the other end is pulled up by the pull-up resistors 9 and 11, respectively, and the first-stage switch SW1. The second input terminal 5d of the microcomputer 5 and the second-stage switch SW2 are electrically connected to the third input terminal 5e of the microcomputer 5.

  When the switch button 7 is pressed and the switch SW1 is turned on, the second input terminal 5d of the microcomputer 5 changes from the high state to the low state, and the microcomputer 5 detects this and commands to narrow the distance measurement area. Is output to the video signal processing circuit 3 and focusing is performed according to a narrow distance measuring area.

  Next, when the switch button 7 is further pushed in and the second-stage switch SW2 is turned on, the third input terminal 5e of the microcomputer 5 changes from the high state to the low state, and the microcomputer 5 Is detected, and a still image is shot and recorded.

  Next, operations related to still image shooting of the video camera of this embodiment will be described with reference to the flowchart shown in FIG.

  When the video camera is turned on (S100), the microcomputer 5 detects the state of the video shooting switch SW0 (not shown in FIG. 1) (S101). (S102), and then proceeds to the determination of whether or not to take a still image.

  If the video shooting switch SW0 is off, the process proceeds to the determination of whether to shoot a still image without shooting a moving image. Next, the microcomputer 5 detects the state of the second input terminal 5d and determines whether the switch SW1 is on or off (S103).

  If the microcomputer 5 determines that the switch SW1 is not on, it determines whether or not the power is turned off (S108). If it is off, the photographing is terminated (S109). The process returns to the step of determining the state of the video shooting switch SW0 (S101).

  If the microcomputer 5 determines in step 103 that the switch SW1 is on, the microcomputer 5 changes the state of the first output terminal 5a, which is the output terminal to the video signal processing circuit 3, and reduces the distance measurement area. (S104) The focus lens 1e is driven so that the subject in the reduced distance measuring area is in focus.

  Next, the microcomputer 5 detects the state of the third input terminal 5e and determines whether the switch SW2 is on or off (S105).

  If the microcomputer 5 determines that the switch SW2 is not on, it determines whether or not the power is turned off (S108). If it is off, the photographing is terminated (S109). The process returns to the step of determining the state of the photographing switch SW0 (S101).

  If the microcomputer 5 determines in step 105 that the switch SW2 is on, the microcomputer 5 captures and records a still image (S106), enlarges the distance measurement area to the original size (S107), and then the power is turned on. It is determined whether or not it is turned off (S108). If it is turned off, shooting is ended (S109). If it is not turned off, the process returns to the step of determining the state of the video shooting switch SW0 (S101).

  Thus, in this embodiment, when the two-stage release switch for photographing a still image is pushed to the first stage, the autofocus distance measuring area is switched by the microcomputer as the photographing mode switching means. In still image shooting, autofocus is performed to focus within a relatively narrow distance measurement area suitable for still images, and still image shooting is performed when the release switch is pressed to the second stage. When the release switch for is not pressed, movie shooting is performed under autofocus conditions suitable for movies, and when the release switch is operated, still image shooting is performed under autofocus conditions suitable for still images. It can be carried out.

  In the first embodiment, the microcomputer as the mode switching unit switches the operation mode of the autofocus in conjunction with the operation of the release switch as the still image shooting switch unit. The exposure mode and the moving image recording method can be switched in conjunction with the operation of a release switch as means.

  Next, in conjunction with the operation of the release switch, which is a still image shooting switch means, the exposure mode is switched, and when shooting a still image, strobe lighting or long exposure can be performed according to the illuminance of the subject, which is not a recorded video image. A second embodiment will be described as an example in which those natural images are recorded as still images but not as moving images.

  FIG. 3 is a principal block diagram of the second embodiment, and FIG. 4 is a flowchart for explaining photographing mode switching of the second embodiment.

  In FIG. 3, the same components as those in the first embodiment are denoted by the same reference numerals.

  In FIG. 3, 1 is a photographing lens, 20 is a CCD, 12 is an auto gain control (automatic gain adjustment) circuit, 13 is a still image recording means, 14 is an aperture control circuit, 15 is a strobe control circuit, 16 is a strobe, and 30 is a strobe. Video signal processing circuit, 4 is an image signal recording means including a video deck, 50 is a microcomputer, 7 is a switch button, 8 is a first spring, 9 is a first pull-up resistor, and SW1 is a first-stage switch. Reference numeral 10 denotes a second spring, 11 denotes a second pull-up resistor, SW2 denotes a second-stage switch, the switch button 7, the first spring 8, the first pull-up resistor 9, and the first-stage switch. The switch SW1, the second spring 10, the second pull-up resistor 11, and the second-stage switch SW2 constitute a two-stage switch.

  The photographing lens 1 is a so-called rear focus type zoom lens, and includes a first fixed lens 1b, a variable power lens 1c as a first moving lens, a second fixed lens 1d, and a second moving lens as a focus lens. 1e, and an actuator for driving the variable power lens 1c and the focus lens 1e, a sensor for detecting the position of the moving lens, and a diaphragm 1f that also functions as a shutter. Here, since the actuator and the sensor are not directly related to the contents of the present invention, they are not shown in FIG.

  A CCD substrate 20a to which the CCD 20 is fixed is fixed to the photographing lens 1 so that the CCD 20 as an imaging element is positioned at the focal position. Further, the CCD 20 has an input terminal 20d for clearing charges accumulated in the CCD 20, and an output terminal 20c.

  The auto gain control circuit 12 (hereinafter referred to as AGC circuit) is provided with first and second input terminals 12a and 12b and an output terminal 12c, and an image inputted from the CCD 20 to the first input terminal 12a. The signal is amplified with a gain corresponding to the amplification signal input from the microcomputer 50 to the second input terminal 12b, and the result is output from the output terminal 12c.

  The video signal processing circuit 30 has a first input terminal 30a, a second input terminal 30b, a first output terminal 30c, and a second output terminal 30d. The first input terminal 30a is the AGC circuit 12 described above. The second input terminal 30 b is electrically connected to the first output terminal 50 a of the microcomputer 50, and the first output terminal 30 c is connected to the image signal recording unit 4. The second output terminal 30d is electrically connected to the input terminal 4a, and the second output terminal 30d is electrically connected to the first input terminal 50b of the microcomputer 50.

  The video signal processing circuit 30 sequentially reads out the result of amplifying the image signal stored in the CCD 20 with a predetermined gain via the first input terminal 30a from the AGC circuit 12, and via the first output terminal 30c. The video signal is output to the image signal recording means 4, and the illuminance information of the subject in the pixel range (photometric area) designated by the microcomputer 50 via the second input terminal 30b is output to the second output terminal 30d. To the microcomputer 50.

  The image signal recording means 4 includes, for example, a video deck, a video tape, a memory card slot, and a memory card, and has a first input terminal 4a, a second input terminal 4b, and an output terminal (not shown). Yes. The first input terminal 4 a of the image signal recording means 4 is electrically connected to the first output terminal 30 c of the video signal processing circuit 30, and the second input terminal 4 b of the image signal recording means 4 is connected to the microcomputer 50. The image signal recording means 4 records the video signal input to the first input terminal 4a or the second input terminal 4b.

  The microcomputer 50 is a well-known microcomputer and includes a first output terminal 50a, a first input terminal 50b, a second output terminal 50c, a second input terminal 50d, a third input terminal 50e, and a third output. It has a terminal 50f, a fourth output terminal 50g, a fifth output terminal 50h, and a sixth output terminal 50i.

  The first output terminal 50 a of the microcomputer 50 is electrically connected to the second input terminal 30 b of the video signal processing circuit 30, and the first input terminal 50 b is the second output terminal of the video signal processing circuit 30. 30d, the second output terminal 50c is electrically connected to the input terminal of the aperture control circuit 14, and the second input terminal 50d is electrically connected to the first-stage electrical switch SW1. The third input terminal 50e is electrically connected to the second-stage electrical switch SW2, the third output terminal 50f is electrically connected to the input terminal 20d of the CCD 20, and the fourth output terminal. 50g is electrically connected to the input terminal of the strobe control circuit 15, the fifth output terminal 50h is electrically connected to the second input terminal 12b of the AGC circuit 12, and the sixth output terminal 50i is Still image recording Is electrically connected to the input terminal means 13. The fourth input terminal 50j is electrically connected to the first output terminal 30c of the video signal processing circuit 30. The seventh output terminal 50k is electrically connected to the second input terminal 4b of the image signal recording means 4.

  The microcomputer 50 designates the size of the photometric area to the video signal processing circuit 30 via the first output terminal 50a according to the state of the second and third input terminals 50d and 50e, and the first input terminal Information on the illuminance of the subject in the photometry area is input from the video signal processing circuit 30 via the reference numeral 50b, and an aperture drive command is output from the second output terminal 5c to the aperture control circuit 14 based on the information. Exposure adjustment is performed by driving a motor (not shown) 14 that drives the diaphragm blades.

  The still image recording unit 13 is a data recording unit including an input terminal and an output terminal (not shown), for example including a flash memory. The input terminal is electrically connected to the sixth output terminal 50 i of the microcomputer 50. The information of the still image obtained by converting the video signal input from the video signal processing circuit 30 into data by the microcomputer 50 through the fourth input terminal 50j is input from the microcomputer 50 and stored.

  The diaphragm control circuit 14 is a known motor drive circuit for driving diaphragm blades, and has an input terminal and an output terminal. The input terminal is electrically connected to the second output terminal 50c of the microcomputer 50, and the output terminal. Is connected to a motor (not shown) that drives the diaphragm blade 1f.

  The diaphragm control circuit 14 drives a motor (not shown) according to a drive command from the microcomputer 50 input to the input terminal, and opens and closes the diaphragm blade 1f according to the illuminance of the subject.

  The strobe control circuit 15 has an input terminal and an output terminal, the input terminal is electrically connected to the fourth output terminal 50 g of the microcomputer 50, and the output terminal is connected to the input terminal of the strobe 16. .

  The strobe control circuit 15 causes the strobe 16 to emit light upon receiving a strobe emission command from the microcomputer 50 from its input terminal.

  The switch button 7, the first spring 8, the second spring 10, the first-stage switch SW1, and the second-stage switch SW2 form a release switch for taking a two-stage still image. One end of the first and second stage switches SW1 and SW2 is grounded, and the other end is pulled up by the pull-up resistors 9 and 11, respectively. SW1 is electrically connected to the second input terminal 50d of the microcomputer 50, and the second-stage switch SW2 is electrically connected to the third input terminal 50e of the microcomputer 50.

  When the switch button 7 is pressed and the switch SW1 is turned on, the second input terminal 50d of the microcomputer 50 changes from the high state to the low state, and the microcomputer 50 detects this and issues a command to narrow the photometric area. Output to the video signal processing circuit 30 and exposure adjustment according to a narrow photometric area is performed.

  Next, when the switch button 7 is further pushed in and the second-stage switch SW2 is turned on, the third input terminal 5e of the microcomputer 50 changes from the high state to the low state, and the microcomputer 50 Is detected, and a still image is shot and recorded.

  Next, operations related to still image shooting by the video camera will be described with reference to the flowchart shown in FIG.

  When the power of the video camera is turned on (S200), the microcomputer 50 detects the state of the video shooting switch SW0 (not shown in FIG. 3) (S201). (S202), and then proceeds to the determination of whether or not to take a still image.

  If the video shooting switch SW0 is off, the process proceeds to the determination of whether to shoot a still image without shooting a moving image.

  Next, the microcomputer 50 detects the state of the second input terminal 50d and determines whether the switch SW1 is on or off (S203).

  If the microcomputer 50 determines that the switch SW1 is not on, the microcomputer 50 determines whether the power is turned off (S218). If it is off, the photographing is terminated (S219). The process returns to the step of determining the state of the video shooting switch SW0 (S201).

  If the microcomputer 50 determines in step 203 that the switch SW1 is on, the microcomputer 50 changes the state of the first output terminal 50a, which is the output terminal to the video signal processing circuit 30, and reduces the photometric area ( In step S204, the illuminance of the subject in the photometry area is measured (S205), and the exposure time and aperture value for proper exposure are calculated with the AGC turned off (gain 1) for the subject in the photometry area (S206).

  Next, the microcomputer 50 detects the state of the third input terminal 50e and determines whether the switch SW2 is on or off (S207).

  If the microcomputer 50 determines that the switch SW2 is not on, the microcomputer 50 determines whether the power is turned off (S218). If it is off, the photographing is terminated (S219). The process returns to the step of determining the state of the video shooting switch SW0 (S201).

  If the microcomputer 50 determines in step 207 that the switch SW2 is on, it first reads a video signal for one field as a moving image from the video signal processing circuit 30 via the fourth input terminal 50j. It is stored (S208). Next, the microcomputer 50 outputs the signal stored in step 208 as a video signal of the moving image to the second input terminal 4b of the image signal recording means 4 via the seventh output terminal 50k. 4 repeatedly records this signal as a moving image signal during still image shooting (S209).

  Next, the microcomputer 50 fixes the gain of the AGC circuit 12 to 1 in order to take a still image (S210), and strobe light emission is necessary based on the calculation result of the appropriate exposure time and the appropriate aperture value calculated in step 206. (S211), if strobe light emission is necessary, the strobe light is emitted and still image shooting is performed (S212). If it is determined that strobe light emission is not necessary, the third output terminal The CCD 20 is cleared through 50f (S213), and still image shooting is performed (S214). At this time, the accumulation in the CCD 20 enables exposure for a period longer than the accumulation time at the time of moving image shooting determined by the period of the video synchronization signal used as a reference when shooting the video of the moving image.

  Next, the microcomputer 50 reads an image signal for one screen from the CCD 20 (S215), converts the read image signal into image data, stores the image data in the still image recording means 13 (S216), and performs photometry. The area size, the gain of the AGC circuit 12, and the shooting state of the moving image shooting are returned to the original state (S217), and it is determined whether the power is turned off (S218). (S219) If not turned off, the process returns to the step (S201) for determining the state of the video shooting switch SW0.

  In this way, in this embodiment, when the two-stage release switch for photographing a still image is pushed to the first stage, the photometry area for automatic exposure adjustment is set by the microcomputer 50 which is the photographing mode switching means. Still image shooting is performed because exposure adjustment is performed to align the exposure within a relatively narrow metering area suitable for still images, and still image shooting is performed when the release switch is pressed to the second stage. When the release switch for is not pressed, movie shooting is performed under exposure conditions suitable for movies, and still image shooting is performed under exposure conditions suitable for still images when the release switch is operated. Can do.

  Further, in this embodiment, when taking a still image, the gain of the AGC circuit is lowered, and the charge accumulation of the appropriate CCD is performed by long-time exposure or strobe light emission. Excellent and beautiful still images can be obtained.

  Furthermore, in this embodiment, since the video of the moving image during still image shooting is repeated with the image immediately before the still image shooting is performed, even if strobe lighting or the like is performed, the moving image is unnatural. No video is recorded.

  Furthermore, in this embodiment, the means for storing the image data of the still image is provided separately from the recording means for recording the moving image, so that the shooting state of the moving image can be restored immediately after the still image shooting is completed. In addition, the image data of the still image can be given a format that can be directly processed by a personal computer, or the operability can be enhanced by using, for example, a PCMCIA flash memory card or the like adapted to the interface of the personal computer.

  In the first and second embodiments described above, the example in which the present invention is applied to autofocus and exposure control has been described. However, the present invention can also be applied to an example in which the characteristics of camera shake correction are switched.

  In the case of camera shake correction, when correcting for moving images, control is performed so that the correction element always returns to the center in order to continue correcting continuous camera shake so that the correction element sticks to the end of the correction range. Although it must be prevented, there is a characteristic that even if there is a slight amount of correction, it feels as if camera shake has been corrected as long as it is within the perceptible range. However, there is no need for control to return to the center because it is sufficient to perform camera shake correction only during the exposure time, but there is a characteristic that it cannot be said that the correction effect is sufficient unless the correction stiffness is set to the same level as the permissible circle of confusion. .

  Therefore, an example in which the characteristics of camera shake correction during moving image shooting and still image shooting are switched will be described as a third embodiment.

  FIG. 5 is a principal block diagram of the “video camera” as an embodiment, and FIG. 6 is a flowchart for explaining the shooting mode switching of this embodiment.

  In FIG. 5, 1 is a photographing lens, 2 is a CCD, 3 is a video signal processing circuit, 4 is an image signal recording means including a video deck, 500 is a microcomputer, 17 is a camera shake correction control circuit, 7 is a switch button, and 8 is a switch button. The first spring, 9 is a first pull-up resistor, SW1 is a first-stage switch, 10 is a second spring, 11 is a second pull-up resistor, SW2 is a second-stage switch, The switch button 7, the first spring 8, the first pull-up resistor 9, the first-stage switch SW 1, the second spring 10, the second pull-up resistor 11, and the second-stage switch SW 2 are in two stages. It constitutes an expression switch.

  The photographing lens 1 is a so-called rear focus type zoom lens, and includes a first fixed lens 1b, a variable power lens 1c as a first moving lens, a second fixed lens 1d, and a second moving lens as a focus lens. 1e, a variable apex angle prism 1g for correcting camera shake, an actuator for driving the variable power lens 1c, the focus lens 1e and the variable apex angle prism 1g, and a moving lens 1c. , 1e, and a diaphragm 1f that also functions as a shutter. Here, since the actuator and the sensor are not directly related to the contents of the present invention except for the actuator 1h for driving the variable apex angle prism, the description is omitted in FIG.

  A CCD substrate 2a to which the CCD 2 is fixed is fixed to the photographing lens 1 so that the CCD 2 as an imaging element is positioned at the focal position.

  The video signal processing circuit 3 has a first input terminal 3a, a second input terminal 3b, and a first output terminal 3c. The first input terminal 3a is electrically connected to the output terminal of the CCD 2. The second input terminal 3b is electrically connected to the first output terminal 500a of the microcomputer 500, and the first output terminal 3c is electrically connected to the input terminal 4a of the image signal recording means 4. Yes.

  The video signal processing circuit 3 sequentially reads out the image signal stored in the CCD 2 through the first input terminal 3a, and outputs it to the image signal recording means 4 as a video signal through the first output terminal 3c. The focus information within the pixel range (ranging area) designated by the microcomputer 500 via the second input terminal 3b is output to the microcomputer 500 via the second output terminal 3d.

  The image signal recording means 4 includes, for example, a video deck, a video tape, a memory card slot, and a memory card, and has an input terminal 4a and an output terminal (not shown). The input terminal 4a of the image signal recording means 4 is electrically connected to the first output terminal 3c of the video signal processing circuit 3, and the image signal recording means 4 records the video signal input to the input terminal 4a.

  The microcomputer 500 is a well-known microcomputer and has a first output terminal 500a, a first input terminal 500b, a second output terminal 500c, a second input terminal 500d, and a third input terminal 500e. .

  The first output terminal 500 a of the microcomputer 500 is electrically connected to the second input terminal 3 b of the video signal processing circuit 3, and the first input terminal 500 b is the second output terminal of the video signal processing circuit 3. 3d, the second output terminal 500c is electrically connected to the first input terminal 17a of the camera shake correction control circuit 17, and the second input terminal 500d is the first-stage electrical switch SW1. The third input terminal 500e is electrically connected to the second-stage electrical switch SW2.

  The microcomputer 500 designates the size of the distance measurement area to the video signal processing circuit 3 via the first output terminal 500a, and from the video signal processing circuit 3 to the inside of the distance measurement area via the first input terminal 500b. Focus information is input, based on that information, a focus drive command is output to a focus drive circuit (not shown), and the focus drive circuit drives a motor (not shown) that drives the focus lens 1e. Is done.

  The camera shake correction control circuit 17 includes a vibration sensor, an integration circuit, a high-pass filter (hereinafter referred to as HPF), and a drive circuit. The camera shake correction control circuit 17 detects vibration with the vibration sensor, and optical shake is performed so that the image on the CCD 2 is not shaken by the vibration. The camera shake correction actuator 1h is controlled so as to drive the variable apex angle prism 1g which is a correction element. In addition, the camera shake correction control circuit 17 changes a frequency characteristic for driving the camera shake correction actuator 1h with respect to the detected vibration in accordance with a signal input to the input terminal 17a.

  The switch button 7, the first spring 8, the second spring 10, the first-stage switch SW1, and the second-stage switch SW2 form a release switch for taking a two-stage still image. One end of the first and second stage switches SW1 and SW2 is grounded, and the other end is pulled up by the pull-up resistors 9 and 11, respectively. SW1 is electrically connected to the second input terminal 500d of the microcomputer 500, and the second-stage switch SW2 is electrically connected to the third input terminal 500e of the microcomputer 500.

  When the switch button 7 is pressed and the switch SW1 is turned on, the second input terminal 500d of the microcomputer 500 changes from the high state to the low state, and the microcomputer 500 detects this and detects the camera shake correction control circuit 17. A command for strongly switching the frequency characteristic to a characteristic for returning to the center position is output to the camera shake correction control circuit 17, and the camera shake correction control circuit 17 shifts the cutoff frequency of the HPF frequency characteristic to the high frequency side. As a result, the variable apex angle prism 1g, which is a camera shake correction element, is positioned substantially at the optically neutral position.

  Next, when the switch button 7 is further pressed and the second-stage switch SW2 is turned on, the third input terminal 500e of the microcomputer 500 changes from the high state to the low state, and the microcomputer 500 Is output to the camera shake correction control circuit 17 to switch the frequency characteristics of the camera shake correction control circuit 17 to characteristics that allow camera shake correction in all frequency bands. The camera shake correction control circuit 17 outputs the frequency characteristics of the HPF. The cut-off frequency is shifted to the low frequency side, and still images are shot and recorded.

  Next, operations related to still image shooting by the video camera will be described with reference to the flowchart shown in FIG.

  When the power of the video camera is turned on (S300), the microcomputer 500 detects the state of the video shooting switch SW0 (not shown in FIG. 5) (S301). (S302), and then proceeds to the determination of whether or not to take a still image.

  If the video shooting switch SW0 is off, the process proceeds to the determination of whether to shoot a still image without shooting a moving image. Next, the microcomputer 500 detects the state of the second input terminal 500d and determines whether the switch SW1 is on or off (S303).

  If the microcomputer 500 determines that the switch SW1 is not on, the microcomputer 500 determines whether or not the power is turned off (S309). If the switch SW1 is off, the photographing ends (S310). The process returns to the step of determining the state of the video shooting switch SW0 (S301).

  If the microcomputer 500 determines in step 303 that the switch SW1 is on, the microcomputer 500 sends a command via the first output terminal 500c that is an output terminal to the camera shake correction control circuit 17, and the camera shake correction control circuit 17 Is switched to a characteristic in which the variable apex angle prism, which is the camera shake correction means, is located at an optically neutral position by shifting the cutoff frequency of the HPF to the high frequency side (S304).

  Next, the microcomputer 500 detects the state of the third input terminal 500e and determines whether the switch SW2 is on or off (S305).

  If the microcomputer 500 determines that the switch SW2 is not on, the microcomputer 500 determines whether the power is not turned off (S309). If the power is off, the shooting is finished (S310). The process returns to the step of determining the state of the photographing switch SW0 (S301).

  If the microcomputer 500 determines in step 305 that the switch SW2 is ON, the microcomputer 500 sends a command via the first output terminal 500c that is an output terminal to the camera shake correction control circuit 17, and the camera shake correction control circuit 17 Is switched to a characteristic in which camera shake correction is effective in a wide frequency range by shifting the cutoff frequency of the HPF to the low frequency side (S306), and a still image is shot and recorded (S307). The frequency characteristic of 17 is returned to a normal value (S308), it is determined whether or not the power is turned off (S309). If it is turned off, the shooting is terminated (S310). The process returns to the step of determining the state of the photographing switch SW0 (S301).

  In this way, in this embodiment, when the two-stage release switch for taking a still image is pushed up to the first stage, the variable apex angle prism, which is a camera shake correction unit, is moved to the optical center position (correction). The camera is located near the (zero position), has little chromatic aberration and image plane tilt, and is suitable for still image shooting. When the release switch is pushed down to the second stage, image stabilization control can be performed in a wide frequency range. The switch is switched to a compatible frequency characteristic, and still image shooting is performed, and the release switch for still image shooting is not pressed to return to the frequency characteristic suitable for camera shake correction after the still image shooting. In some situations, it is possible to prevent a situation where the camera is not able to perform camera shake correction due to a camera being shot under the camera shake correction conditions suitable for the movie and the correction means hitting the end of the correction range. When the zoom switch is operated, camera shake correction corresponding to a wide frequency band is performed in the vicinity of the optical neutral position suitable for a still image, so there is no optical adverse effect such as chromatic aberration, and accurate camera shake correction can be performed. .

The figure which shows the structure of the principal part of Example 1. Flowchart showing the operation of the first embodiment. The figure which shows the structure of the principal part of Example 2. The flowchart which shows operation | movement of Example 2. The figure which shows the structure of the principal part of Example 3. Flowchart showing the operation of the third embodiment.

Explanation of symbols

1 Shooting Lens 3 Video Signal Processing Circuit 5 MPU

Claims (1)

An imaging device that can shoot movies and still images,
Optical image stabilization means;
And control means for controlling the frequency characteristic of the operation of the optical camera shake correction means for detecting the vibration,
Release means having a multi-stage switch for still image shooting;
With
It said control means in response to said operation of the first stage of the switches of the plurality of stages according to the operation of the release means, said optical shake cutoff frequency characteristic of the operation of the correction means at the time of moving image shooting The frequency is switched from the frequency to the high frequency side, and the cut-off frequency is switched to the low frequency side in accordance with the operation of the second-stage switch so that the frequency characteristics of the operation of the optical image stabilization means are different from those during moving image shooting. An imaging apparatus characterized by being controlled to the above.

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