JP2003264734A - Image pickup device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image pickup device which does not output a blurred image acquired in deciding whether or not the focus position of a photographing lens is changed as an image pickup result. <P>SOLUTION: On the basis of an image inputted while driving the photographing lens in an optical axis direction, the initial focus position (x=x10) of the photographing lens is detected and set before acquiring a first photographing image from the time t=N (sec), the photographing lens is driven to the initial focus position in acquiring first to third photographing images for recording/display, the photographing lens is driven to positions (x=x9, x11) driven from the initial focus position to the front and back in the optical axis direction in acquiring first and second adjustment images not to be used for recording/display and the photographing images and the adjustment images are alternately acquired. An evaluation value is calculated for three images 7D composed of the second photographing image and the first and second adjustment images acquired before and after that and whether or not the focus position of the photographing lens is changed while photographing moving images is decided on the basis of the evaluation value. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a technique for continuously capturing images.

[0002]

2. Description of the Related Art Conventionally, as an autofocus technique in an image pickup apparatus such as a digital camera, a photographing lens is driven back and forth to find a position where the contrast of an image is maximum, and the position is specified as a focusing position of the photographing lens. Contrast type (so-called mountain climbing type) autofocus is known.

FIG. 12 is a schematic diagram showing a curve CL representing the relationship between the evaluation value and the position x of the taking lens in the optical axis direction.
As shown in FIG. 12, the evaluation value is the largest when the taking lens is at the in-focus position (x = xv). The contrast autofocus operation is performed by comparing the evaluation values of at least two captured images that are captured with different positions x in the optical axis direction of the taking lens. Specifically, the evaluation values of the two images are compared, and the taking lens is driven in the direction in which the evaluation value becomes larger. Then, by repeating such an operation and driving the taking lens, the taking lens can be driven to the in-focus position.

By the way, in photographing time-continuous images such as moving images, the subject moves during photographing to change the focus position of the photographing lens. By comparing the evaluation values of at least two captured images that are captured while the position x in the optical axis direction of the capturing lens is different during capturing of images that are temporally continuous, the subject moves and There is a need to determine whether the focus position has changed.

13 and 14 are schematic diagrams illustrating a method for determining whether or not the in-focus position of the photographing lens has changed due to the movement of the subject. In FIG. 13, the subject is moving. A curve CL1 representing the relationship between the evaluation value when there is no image and the position x in the optical axis direction of the taking lens is illustrated. FIG. 14 shows the evaluation value before and after the movement of the subject and the taking lens when the subject is moving. Position x of optical axis
Curves CL1 and CL2 representing the relationship with are illustrated.

In the case of FIG. 13, the previous focus position of the taking lens (x = xv) and the previous focus position of the taking lens (x
= Xv), the position of the taking lens in the direction of retracting the lens (x = xu), and the focus position of the previous taking lens (x
= Xv), the evaluation value at the position (x = xw) of the taking lens in the direction of extending the lens is compared, and the position of the taking lens having the maximum evaluation value is the focus position (x = xv) of the previous taking lens. ), It can be determined that the focus position of the taking lens has not changed.

Further, in the case of FIG. 14, the focus position (x = x) of the previous photographing lens is evaluated with respect to the evaluation value after the movement of the object.
v), the position of the previous shooting lens in the focused state (x = xv)
The position of the taking lens in the direction of retracting the lens from (x = x
u), and the focus position of the previous shooting lens (x = xv)
The position of the shooting lens in the direction to extend the lens from (x = x
The evaluation values (C = C2v, C2u, C2w) in w) are compared. In this case, the evaluation value (C = C2v) at the photographing lens position (x = xw) is more than the evaluation value (C = C2v) at the previous focusing position (x = xv) of the photographing lens.
Since w) is larger, the position of the taking lens with the maximum evaluation value is the focusing position of the previous taking lens (x =
Since it is understood that it is not xv), it can be determined that the focus position of the taking lens has changed.

[0008]

However, in the above-mentioned autofocus operation, at least two pieces of the photographing lens are made different in position x in the optical axis direction during photographing of time-continuous images such as moving images. When it is necessary to capture a photographed image and the subject as shown in FIG. 13 is not moving, the focus position (x = x
Other than v), an image in which the subject is blurred is captured. Further, when the subject moves as shown in FIG. 14, the subject becomes more blurred at the position (x = xu) of the taking lens in the direction in which the lens is retracted from the focus position (x = xv) of the previous taking lens. The captured image will be taken.

Therefore, in the above-described autofocus operation, a blurred image is captured and a blurred image is recorded / displayed both when the subject is not moving and when the subject is moving. Causes problems such as.

The present invention has been made in view of the above problems, and provides an image pickup apparatus which does not output a blurred image obtained when it is determined whether or not the in-focus position of the taking lens has changed. The purpose is to provide.

[0011]

In order to solve the above-mentioned problems, the invention of claim 1 is an image pickup apparatus for obtaining and outputting first to third photographed images which are temporally consecutive, and a photographing lens. Based on an image that is input while being driven in the optical axis direction, a detection unit that detects the in-focus position of the photographing lens before the acquisition of the first captured image, and after the acquisition of the first captured image. An image for acquiring the first adjusted image by the time when the acquisition of the second captured image is started, and an image for acquiring the second adjusted image after the acquisition of the second captured image and before the start of the acquisition of the third captured image An acquisition means and a state in which the photographing lens is driven to the in-focus position at the time of acquiring the first and second captured images, and the capturing lens is focused at the time of acquiring the first and second adjusted images. Drive back and forth from the position in the optical axis direction A drive control means for setting a state, a determination means for determining a focus state of the photographing lens based on the second captured image, and the first and second adjusted images, and the first and second It is characterized in that the second adjusted image is skipped and the first to third photographed images are continuously output.

According to a second aspect of the present invention, in an image pickup apparatus which acquires and outputs temporally continuous first and second photographed images, an image input while driving the photographing lens in the optical axis direction is used. Based on the detection means for detecting the in-focus position of the photographing lens before the acquisition of the first photographed image, a plurality of detection means are provided after the acquisition of the first photographed image until the start of the acquisition of the second photographed image. An image acquisition unit that acquires an adjusted image; a state in which the photographing lens is driven to the in-focus position when the first and second photographed images are acquired; The focus state of the photographing lens is determined based on the drive control means for driving the lens in the optical axis direction back and forth from the focus position, the first or second photographed image, and the plurality of adjusted images. Judgment means to judge Comprising, by skipping the plurality of adjustment images, and outputs in succession the first and second captured image.

According to a third aspect of the present invention, in an image pickup apparatus that acquires and outputs first to third photographed images that are temporally continuous, the image input while driving the photographing lens in the optical axis direction is used. Based on the detection means for detecting the in-focus position of the photographing lens before the acquisition of the first photographed image, a plurality of detection means are provided after the acquisition of the first photographed image until the start of the acquisition of the second photographed image. The first adjusted image consisting of adjusted images,
And image acquisition means for respectively acquiring a second adjusted image group including a plurality of adjusted images from the acquisition of the second captured image to the start of acquisition of the third captured image, and the first and second image acquisition means. The photographing lens is driven to the in-focus position when the photographed image of
Drive control means for keeping the photographing lens in the state of being driven back and forth in the optical axis direction from the in-focus position when the adjustment image group is acquired, the second photographed image, and the first and second adjusted images. Group for determining the next focus position of the taking lens based on the group, and skipping the first and second adjusted image groups, and successively connecting the first to third taken images. It is characterized by outputting as.

According to a fourth aspect of the present invention, in an image pickup apparatus which acquires and outputs first and second photographed images which are continuous in time, an image which is input while driving the photographing lens in the optical axis direction is used. Based on the detection means for detecting the in-focus position of the photographing lens before the acquisition of the first photographed image, a plurality of detection means are provided after the acquisition of the first photographed image until the start of the acquisition of the second photographed image. An image acquisition unit that acquires an adjusted image; a state in which the photographing lens is driven to the in-focus position when the first and second photographed images are acquired; The next focus of the photographing lens is determined based on the drive control means for driving the lens in the optical axis direction back and forth from the focus position, the first or second photographed image, and the plurality of adjusted images. And a determination means to determine the position For example, skipping the plurality of adjustment images, and outputs in succession the first and second captured image.

According to a fifth aspect of the present invention, in the image pickup apparatus according to any one of the first to fourth aspects, the image acquisition unit lowers the resolution of each captured image and adjusts each adjusted image. It is characterized by acquiring.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

<First Embodiment><Structure of Main Part of Imaging Device 1> FIG. 1 is a perspective view showing an imaging device 1 according to a first embodiment of the present invention. 2 is a rear view of the image pickup apparatus 1. 1 and 2, in order to clarify the azimuth relationship, X, Y, and
The three axes of Z are shown.

As shown in FIG. 1, a taking lens 11 and a finder window 2 are provided on the front side of the image pickup apparatus 1. A CCD image pickup device 30 is provided inside the photographing lens 11 as an image generation unit for photoelectrically converting a subject image incident through the photographing lens 11 to generate an image signal (a signal including an array of pixel data for each pixel). It is provided.

The photographic lens 11 includes a lens system which can be driven along the optical axis direction. By driving the lens system in the optical axis direction, a subject image formed on the CCD image pickup device 30 is formed. It is configured so that a focused state can be realized.

A shutter button 8 and a photographing mode switching button 14 are arranged on the upper surface side of the image pickup apparatus 1. The shutter button 8 is a button that is pressed by the user when shooting a subject and gives a shooting instruction to the image pickup apparatus 1. Here, the shutter button 8 is half-pressed (S1) to perform an autofocus operation described later, and the fully-pressed state (S2) is to perform a main shooting described later. In the moving image shooting mode described later, the moving image shooting is started and ended by pressing the shutter button 8.

The shooting mode switching button 14 is a button for manually selecting and setting a shooting mode at the time of shooting operation by the image pickup apparatus 1, that is, switching between a still image shooting mode and a moving image shooting mode.

A memory card 9 for recording image data obtained by a main photographing operation in response to a user pressing the shutter button 8 is provided on the side surface of the image pickup apparatus 1.
The mounting portion 15 for mounting the memory card 9 is formed so that the replaceable memory card 9 can be mounted. Further, a card take-out button 7 that is pressed down when taking out the memory card 9 from the wearing section 15 is arranged so that the memory card 9 can be taken out from the wearing section 15.

Further, as shown in FIG. 2, the rear view of the image pickup apparatus 1 is for changing the various setting states of the liquid crystal display section 16 for displaying a live view image, a photographed image, etc. The operation button 17 and the finder window 2 are provided.

<Functional Block of Imaging Device 1> FIG. 3 is a block diagram showing an internal configuration of the imaging device 1. As shown in FIG. 3, the image pickup apparatus 1 includes a photographing function unit 3 for processing an image signal, an optical system control unit 150 for realizing autofocus control, and a timing control unit 160 for controlling timing of image acquisition and the like. The lens drive unit 110, and the camera control unit 100 that comprehensively controls each unit provided in the imaging device 1.

The CCD image pickup device 30 functions as an image pickup means (image acquisition means) for picking up a subject image to generate an electronic image signal, has 1280 × 960 pixels, and has a photographing lens 11. The optical image of the object formed by the image signal of R (red), G (green), and B (blue) color components for each pixel (a signal consisting of a signal sequence of pixel signals received by each pixel) To photoelectrically convert the image signal to output the image signal. Here, the photoelectric conversion of the light image of the subject by exposing the CCD image pickup device 30 is defined as “acquisition of image”. The timing control unit 160 generates various timing pulses for controlling the driving of the CCD image pickup device 30 and the like. Here, the CCD image pickup device 30 generates and outputs an image signal for 60 frames per second. Are controlled. The timing controller 160 will be described later in detail.

There are three driving modes (reading modes) for the CCD image pickup device 30: a draft mode, an automatic focusing mode, and a main photographing mode.

The draft mode is applied during a so-called live view display, which is a read mode for generating an image for live view display for previewing before actual photographing. Generally, the signal reading from the CCD image pickup device is performed for each horizontal line. Therefore, in the draft mode, when reading a pixel signal for each horizontal line from the CCD image sensor 30 having 1280 pixels in the horizontal direction and 960 pixels in the vertical direction, one line out of four lines is read out by C.
The CD image pickup device 30 is driven. That is, in the draft mode, the horizontal lines of 960 are read while being thinned out by 1/4. As a result, the image output from the CCD image pickup device 30 in the draft mode is 128
It is composed of 0 × 240 pixels.

The automatic focusing mode is a reading mode applied during the automatic focusing control. In the automatic focusing mode, it is read in the draft mode 24
Of 0 lines, 80 lines located in the center are read. As a result, the image output from the CCD image pickup device in the automatic focusing mode is composed of 1280 × 80 pixels.

Further, the main photographing mode is a mode in which an image signal is read out for the entire frame, that is, all pixels of 1280 × 960. Then, the timing control unit 160 controls the drive timing of the CCD image pickup device 30 in the designated mode among these read modes. Further, in the moving image shooting mode, the CCD image pickup device 30 is 1280 × 960 in the main shooting mode.
The image signal having the pixels is read out for 30 frames per second.

Further, in the moving image photographing mode, the CCD
The image sensor 30 is 1280 × 96 in the main shooting mode.
While reading the image signal having 0 pixels for 30 frames per second, the image signal having 1280 × 80 pixels in the automatic focusing mode is read. That is, in the moving image shooting mode, the CCD image pickup device 30 stores the image signal for recording / display having 1280 × 960 pixels (hereinafter referred to as “shot image”) in the main shooting mode and 1280 in the automatic focusing mode. Image signal for autofocus control having × 80 pixels (hereinafter referred to as “adjusted image”)
And are read alternately to read image signals for 60 frames per second. The timing control unit 160 also controls the driving timing of the CCD image pickup device 30 in the moving image shooting mode.

As described above, the image signal obtained from the CCD image pickup device 30 is given to the A / D converter 40.

The A / D converter 40 is a CCD image pickup device 30.
The image signal (analog signal) output from the device is converted into, for example, a 10-bit digital signal per pixel. A / D
The image signal output from the converter 40 is stored in the image memory 70.
Be led to.

The image memory 70 is for temporarily storing the image signal, and when the image is recorded on the memory card 9 or displayed on the liquid crystal display unit 16, the image signal is processed by the image processing unit. Lead to 50.

When the shutter button 8 is pressed, it is necessary to perform autofocus control before performing the shooting operation of the main shooting. Therefore, before performing the main photographing operation, the optical system control unit 150 drives the lens position of the photographing lens 11 stepwise in the optical axis direction, and the camera control unit 10
The image signal captured at each lens position of the taking lens 11 is stored in the image memory 70 under the control of 0 and the timing control unit 160.

In the moving image shooting mode, CC
The D image pickup device 30 displays the captured image (1
(280 × 960 pixels) and the adjusted image (1280 × 80 pixels) in the automatic focusing mode are read alternately to read the image signals for 60 frames per second, so the image memory 70 has 1280 × 960 pixels. The photographed image having the pixel number and the adjusted image having the 1280 × 80 pixels are alternately input from the A / D converter 40. In other words, image signals for 60 frames per second are continuously stored in the image memory 70 during moving image shooting.

The image processing section 50 performs image processing such as white balance adjustment, γ correction and color correction on the image signal. The image signal output from the image processing unit 50 is guided to the resolution conversion unit 60.

The resolution conversion section 60 includes a CCD image pickup device 30.
The predetermined resolution conversion is performed on the image data obtained from.

For example, at the time of live view display before photographing, the resolution conversion unit 60 performs a predetermined resolution conversion on the image data obtained by driving the CCD image pickup device 30 in the draft mode, and the display on the liquid crystal display unit 16 is performed. Image data (320 × 240 pixels) having an image size suitable for the number of pixels is generated. In other words, during live view display, the resolution conversion unit 60 is 128 obtained by the CCD image pickup device 30.
The live view image having 320 × 240 pixels is generated by performing 1/4 thinning-out only on the horizontal direction of the image having 0 × 240 pixels. Note that the resolution conversion unit 60 does not perform resolution conversion processing at the time of actual shooting,
The image data obtained from the image processing unit 50 is directly output to the image compression unit 80.

Further, at the time of shooting a moving image, the resolution is changed from the image memory 70 to the resolution conversion unit 60 via the image processing unit 50 at 30 seconds per second.
A captured image (1280 × 960 pixels) for a frame is input, and the resolution conversion unit 60 transfers the captured image input from the image memory 70 via the image processing unit 50 to the image compression unit 80 without performing resolution conversion processing. A captured image (1280 × 960 pixels) input from the image processing unit 50 in order to output and display a live view during movie shooting
1/4 thinning is performed in the horizontal and vertical directions to generate a display image (320 × 240 pixels) having an image size suitable for the number of display pixels of the liquid crystal display unit 16 and output the liquid crystal display unit 16 with the liquid crystal display. A live view image (display image) consisting of 30 frames per second based on the captured image is displayed in the section 16.

The optical system controller 150 is configured to acquire the image signal stored in the image memory 70 and perform the contrast type autofocus operation. And
After the autofocus control by the optical system control unit 150 is performed and the taking lens 11 is driven to the in-focus position, the shooting operation of the main shooting is performed, and 1280 obtained by the main shooting is performed.
An image signal having × 960 pixels is provided to the image compression unit 80.

In the moving image photographing mode, the optical system controller 150 drives the photographing lens 11 to the in-focus position by the autofocus control and starts the main photographing.
The optical system controller 150 controls the shooting lens 1 when the subject moves.
It determines whether or not the in-focus position of 1 has changed and follows the movement of the subject to control the auto-focus operation of detecting the changed in-focus position of the photographing lens 11. The autofocus operation in the moving image shooting mode will be described later.

As described above, the timing control section 160 generates various timing pulses for controlling the driving of the CCD image pickup device 30 and the like, and also drives timing of the photographing lens 11, the optical system control section 150 and the photographing function. The timing of various processes in each unit of the unit 3 is controlled. The control of the processing timing of each unit by the timing control unit 160 in the autofocus control during moving image shooting will be further described later.

The image compression section 80 is configured to perform an image compression process by a predetermined compression method on a photographed image (1280 × 960 pixels) obtained by actual photographing.
An image signal (recorded image) subjected to image compression is output from the image compression unit 80 and stored in the memory card 9.

The camera control unit 100 is realized by the CPU executing a predetermined program, and when the user presses various buttons including the shutter button 8, the photographing mode switching button 14, and the operation button 17, the operation is performed. It is configured to control each unit of the photographing function unit 3, the optical system control unit 150, and the timing control unit 160 according to the content.

Further, the camera control unit 100 is linked to the optical system control unit 150 and the timing control unit 160, and during the autofocus control, the optical system control unit 150 and the timing control unit 160 gradually change the lens position of the taking lens 11. When driven, it controls the image pickup operation of the CCD image pickup device 30 at each lens position together with the timing control section 160. In the moving image shooting mode, the camera control unit 100 starts moving image shooting when the user presses the shutter button 8 and ends moving image shooting when the user presses the shutter button 8 again.

The lens driving section 110 includes an optical system control section 15
It is a drive unit for driving the taking lens 11 along the optical axis in response to a command from 0, and changes the focus state of the subject image formed on the CCD image pickup device 30.

<Regarding Optical System Control Unit 150> As shown in FIG. 3, the optical system control unit 150 includes an image acquisition unit 151,
The evaluation value calculation unit 152, the drive control unit 153, the focus position detection unit 154, and the focus determination unit 155 are provided.
The image signal stored in the image memory 70 is acquired, and the autofocus control by the contrast method is performed. In other words, the photographing lens 11 operates so as to guide the subject image formed on the CCD image pickup device 30 to the in-focus position.

Further, the optical system control unit 150 has different functions in the autofocus control depending on the photographing mode set by the operation of the photographing mode switching button 14. Here, the moving image photographing mode which is a feature of the image pickup apparatus 1 is used. The function of each unit of the optical system control unit 150 will be described, and when the still image shooting mode or the like is set, the description is omitted because it is similar to the general autofocus control by the contrast method.

The image acquisition unit 151 acquires the image data input to the image memory 70 from the image memory 70.

In the moving image photographing mode, the image memory 7
In 0, a captured / recorded image having 1280 × 960 pixels and an adjustment image for autofocus control having 1280 × 80 pixels are alternately stored from the A / D converter 40. , Not only the adjusted image but also the captured image is used for autofocus control.

Therefore, when the captured image (1280 × 960 pixels) is stored in the image memory 70, the image acquisition unit 151 is located at the center of the captured image from the captured image stored in the image memory 70. AF evaluation area (32
Of the image components of 0 × 320 pixels), a 320 × 80 image component obtained by decimating in the horizontal direction only is acquired. In addition, the adjusted image (1280 × 80
When (pixel) is stored, the 320 × 80 image component corresponding to the AF evaluation area located in the central portion is acquired from the adjusted image stored in the image memory 70. That is,
The image acquisition unit 151 corresponds to 60 frames per second 3
Image data having 20 × 80 pixels is acquired.

The evaluation value calculation unit 152 includes an image acquisition unit 151.
Taking lens 1 based on the image data acquired by
An evaluation value regarding the in-focus state of 1 is obtained. This evaluation value is
Similar to what is performed in the above-mentioned general autofocus operation of the contrast method, it is obtained as the sum of the contrast values in the AF evaluation area.

The drive control section 153, under the control of the timing control section 160 and the camera control section 100, acquires image data for autofocus control or sets the taking lens 11 at the in-focus position when shooting a moving image. The drive of the photographing lens 11 in the optical axis direction is controlled so as to lead to the in-focus position detected by the detection unit 154. Further, at the time of shooting a moving image, when the driving of the photographing lens 11 to the in-focus position is completed, the drive control unit 153 sends a signal indicating that to the camera control unit 100 and the timing control unit 160.
Then, the determination of the in-focus state of the taking lens 11 described later is started. The control of the drive of the taking lens 11 by the drive control unit 153 at the time of shooting a moving image will be described later.

The in-focus position detecting section 154 has a general contrast when the moving image capturing is started and when the in-focus determining section 155 determines that the position of the in-focus state of the taking lens 11 has changed. Similar to the autofocus operation of the method, the focus position of the taking lens 11 is detected based on the evaluation value calculated by the evaluation value calculation unit 152.

FIG. 4 is a schematic diagram showing a curve CLf representing the relationship between the evaluation value at the start of moving image shooting or during moving image shooting and the position x of the taking lens 11 in the optical axis direction. In the moving image shooting mode, when the user gives an instruction to start moving image shooting by pressing the shutter button 8,
The focusing lens 155 is used by the focus determination unit 155 during movie shooting.
When it is determined that the in-focus position of No. 1 has changed, a general contrast autofocus operation is performed, and
As shown in, the focus position detection unit 154 detects the lens position (initial focus position (x = x10)) of the taking lens 11 having the largest evaluation value. That is, here, the focus position detection unit 154 updates and sets the initial focus position of the taking lens 11 each time the focus position of the taking lens 11 is detected at the start of moving image shooting and during the moving image shooting.

The focus determination unit 155 determines, based on the evaluation value calculated by the evaluation value calculation unit 152, during moving image shooting.
It is determined whether or not the focus position of the taking lens 11 has changed.

5 and 6 are schematic views illustrating a method of determining whether or not the in-focus position of the photographing lens 11 has changed due to the movement of the subject, and FIG. 5 shows the method shown in FIG. A curve CL representing the relationship between the evaluation value and the position x of the taking lens 11 in the optical axis direction when the subject has not moved since the initial focus position (x = x10) of the taking lens 11 was detected.
f is illustrated, and in FIG. 6, the evaluation value and the light of the photographing lens 11 when the subject is moving from the time when the initial focus position (x = x10) of the photographing lens 11 shown in FIG. 4 is detected. A curve CLm representing the relationship with the axial position x is illustrated. It should be noted that here, 3 in the optical axis direction of the taking lens 11 is used.
It is assumed that the two positions (x = x9, x10, x11) are equidistantly separated by a predetermined unit adjustment distance Δx (not shown), and a distance corresponding to an integral multiple of the unit distance is called an adjustment distance.

In the case of FIG. 5, the evaluation value (C = C10) at the initial focus position (x = x10) of the taking lens 11
And a lens position (x = x9) in a direction in which the lens is moved by a predetermined adjustment distance from the initial focus position (x = x10), and a direction in which the lens is moved by an adjustment distance in the initial focus position (x = x10). The evaluation value (C = C9, C11) at the lens position (x = x11) is compared. Then, from these evaluation values (C9, C10, C11), it is determined that the position of the taking lens 11 having the maximum evaluation value is the initial focus position (x = x10), and the focus position of the taking lens 11 is determined. Is determined to have not changed.

In the case of FIG. 6, the evaluation value (C = C1) at the initial focus position (x = x10) of the taking lens 11 is obtained.
0), the lens position (x = x9) in the direction in which the lens is moved by the adjustment distance from the initial focus position (x = x10), and the direction in which the lens is moved by the adjustment distance in the initial focus position (x = x10). The evaluation value (C = C9, C11) at the lens position (x = x11) is compared. Then, the evaluation value (C = C10) at the initial focus position (x = x10)
Rather than the evaluation value at the lens position (x = x11) (C
= C11) is larger, the position of the taking lens 11 having the maximum evaluation value is the initial focus position (x = x
It is determined that it is not 10), and it is determined that the focus position of the taking lens 11 has changed. In addition, here, the photographing lens 1
In addition to the change determination of the in-focus position of 1, it is also possible to determine that the position of the taking lens 11 having the maximum evaluation value is in the direction of the lens position (x = x11). That is, the direction determination for determining the direction of the position of the taking lens 11 having the maximum evaluation value is also performed.

Further, during the moving image shooting, the focus determination unit 1
55 determines whether or not the in-focus position of the taking lens 11 has changed, and transmits the result to the camera control unit 100 and the drive control unit 153. Then, as long as the in-focus position of the taking lens 11 does not change, as shown in FIGS. 5 and 6, the taking lens 11 is driven by the adjustment distance under the control of the drive control unit 153, and the taking lens 11 is driven. The evaluation value calculation unit 152 calculates the evaluation value for the image acquired at the position 11 (x = x9, x10, x11), and the focus determination unit 155 determines that the position of the taking lens 11 having the maximum evaluation value is the initial position. The determination as to whether it is the same as the focus position (x = x10) is repeated. That is, the focus determination unit 155 repeatedly determines whether or not the focus position of the taking lens 11 has changed.

When the in-focus position of the taking lens 11 is changed, a general contrast type autofocus operation is performed based on the direction determination result in the in-focus determining unit 155, and the taking lens 11 is moved. The camera is driven to the next initial focus position, and the drive control unit 153 sends to the camera control unit 100 and the timing control unit 160 a signal indicating completion of driving of the taking lens 11 to the next initial focus position.
Then, as shown in FIG. 5 and FIG. 6 described above again, under the control of the drive control unit 153, the image pickup lens 11 is driven by an adjustment distance before and after the next initial focus position to acquire an image. , Taking lens 1 based on that image
The focus determination unit 155 repeatedly determines whether or not the focus position of 1 has changed.

<Regarding Position of Shooting Lens 11 and Various Operation Timings> Next, the position of the shooting lens 11 during shooting of a moving image in the image pickup apparatus 1 and image acquisition, lens driving, and focusing controlled by the timing control unit 160. Various operation timings such as determination will be described.

FIG. 7 is a diagram exemplifying the relationship between the position of the photographing lens 11 and various operation timings such as image acquisition during moving image photographing, driving of the photographing lens 11, and focus determination. In the vertical direction, the image acquisition timing (exposure timing), transfer timing, lens driving timing, shooting lens position, evaluation value calculation and focus determination timing, and recording timing are shown in the vertical direction. There is. The position of the taking lens 11 in FIG. 7 is shown in correspondence with the position of the taking lens 11 illustrated in FIGS. 5 and 6.

Further, in FIG. 7, the time t = N (se) based on the image input while driving the taking lens 11 in the optical axis direction by a general autofocus operation.
Before acquisition of the first captured image from c), the focus position detection unit 1
54 detects the in-focus position (x = x10) of the taking lens 11 and sets it as the initial in-focus position, the taking lens 11 moves to the initial in-focus position (x = x10), and the first captured image It is assumed that the acquisition of is started.

Image acquisition timing (exposure timing)
Is a timing control unit 160 and a camera control unit 100.
Under the control of 1., the timing at which the CCD image pickup device 30 is exposed, that is, the timing at which an optical image of a subject is photoelectrically converted to obtain an image. As shown in FIG. 7, here,
From time t = N, N + 1/30, N + 1/15 (sec), the CCD image sensor 30 acquires first to third captured images that are temporally continuous. Further, time t = N + 1/60, N + 1/20, N + 1/10 (se
From c), in the CCD image pickup device 30, the first to third
The adjustment images of are acquired respectively. That is, the first adjusted image is acquired from the acquisition of the first captured image to the acquisition of the second captured image, and the first adjusted image is acquired from the acquisition of the second captured image to the acquisition of the third captured image. Obtain the adjusted image of No. 2.
Further, the third adjusted image is acquired after the acquisition of the second captured image.

The transfer timing is such that the captured image and the adjusted image acquired by the CCD image pickup device 30 are transferred from the CCD image pickup device 30 through the A / D converter 40 to the image memory 7.
This is the timing for storing 0. As shown in FIG.
The first to third photographed images and the first to third adjusted images are taken by the CCD image pickup device 3 immediately after the respective images are acquired.
0 to the image memory 70.

Further, here, the CCD image pickup device 30 obtains each adjusted image with the resolution lower than that of each taken image, so that each adjusted image is acquired from the CCD image pickup device 30 rather than the image memory. The transfer time up to 70 can be shortened.

The lens driving timing is a timing for driving the taking lens 11 back and forth with respect to the optical axis direction under the control of the timing controller 160 and the drive controller 153. As shown in FIG. 7, under the control of the drive control unit 153, the photographing lens 11 is driven back and forth with respect to the optical axis direction by an adjustment distance between the acquisition of each image, and the first to third
The first and second photographing lens 11 are driven to the initial focus position (x = x10) when the photographed image is acquired.
It is assumed that the photographing lens 11 is driven back and forth from the initial focus position (x = x10) in the optical axis direction by the adjustment distance when the adjustment image is acquired. That is, when the first and second adjusted images are acquired, the taking lens 11 is set to the first and second adjustment images, respectively.
The initial focus position (x = x10), which is the position of the photographic lens 11 when the captured image is acquired, is driven to two different lens positions (x = x9, x11) that are the front and rear. Note that when taking the third adjusted image, the taking lens 1
1 is a state in which the taking lens 11 is driven according to a focus determination result described later.

The evaluation value calculation timing is the evaluation value calculation unit 1
52 is a timing for calculating an evaluation value for the image stored in the image memory 70 at 52, and the focus determination timing is that the focus position of the taking lens 11 is changed based on the evaluation value calculated by the evaluation value calculation unit 152. This is the timing for determining whether or not. As shown in FIG. 7, after the first to third photographed images and the first and second adjusted images are respectively transferred to the image memory 70, the evaluation value calculation unit 152 immediately after the first to third images are transferred. Evaluation values are respectively calculated for the three captured images and the first and second adjusted images. Then, here, time t = N + 1/15 (se
The evaluation value is calculated for the second adjusted image from c), and the focus determination unit 155 calculates the evaluation value based on the evaluation values of the second captured image and the three images 7D including the first and second adjusted images. It is determined whether the focus position of the taking lens 11 has changed. That is, here, the second captured image,
Based on the first and second adjustment images acquired before and after the second photographed image, it is possible to determine the focus state of the photographing lens 11.

Then, the focus determination section 155 transmits the determination result to the camera control section 100 and the drive control section 153,
In response to the result, the camera control unit 100 and the drive control unit 153 control the drive of the taking lens 11. Specifically, as long as the in-focus position of the photographing lens 11 has not changed, the position of the photographing lens 11 (x
= X9, x10, x11), the evaluation value calculation unit 152 calculates an evaluation value for the image, and the focus determination unit 155 causes the focus determination unit 155 to take the maximum evaluation value calculated by the evaluation value calculation unit 152. The determination as to whether or not the position is the same as the initial focus position (x = x10) is repeated. Therefore, when the focus position of the taking lens 11 has not changed, at the start of acquisition of the third adjusted image (time t =
Position the photographing lens 11 at (N + 1/10) (x = x9)
To a state where the time t = N + 1/60
Various operations are performed at the same timings as various processing timings such as image acquisition up to N + 1/10 (sec), lens driving, and focus determination to determine the focus state of the taking lens 11.

When the in-focus position of the photographic lens 11 has changed, the in-focus determination unit 155 determines that the in-focus position of the photographic lens 11 has changed, and the photographic lens 11 having the maximum evaluation value. Since the direction of the position of the camera is also determined, the focus determination unit 155 to the camera control unit 100 and the drive control unit 1
Immediately after transmitting the determination result to 53, a general contrast type autofocus operation is started based on the direction determination result, and the focus position detection unit 154 detects and determines the next initial focus position, After the photographing lens 11 is driven to the next initial focus position, various operations are performed again at timings similar to various processing timings such as image acquisition from time t = N (sec), lens driving, and focus determination. Under the control of the drive control unit 153, the evaluation value calculation unit 152 calculates an evaluation value for the image acquired while driving the taking lens 11 before and after the next initial focus position by the adjustment distance, and the focus determination unit The photographing lens 11 having the maximum evaluation value at 155
It is determined whether the position of is the same as the initial focus position (x = x10).

In this case, the focus determination section 155 determines the second captured image and the first and second captured images that are to be used when determining whether or not the focus position of the photographic lens 11 has changed.
After the adjustment image is acquired, the third captured image is acquired with the position of the photographing lens 11 as the initial focus position (x = x10). This is the photographing lens 11 in the focus determination unit 155.
Since it takes some time to determine the in-focus state of, the time t =
The taking lens 11 is not unnecessarily driven until a focus determination result from N + 1/15 (sec) is obtained. Therefore, here, in order not to blur the shot image for shooting / display until the determination result is obtained, it is assumed that the focus position of the shooting lens 11 has not changed.
When acquiring the third photographed image, the photographing lens 11 is returned to the initial focus position.

The recording timing is the timing for performing the recording process on the memory card 9 using the captured image as the recorded image. As shown in FIG. 7, for the first and second captured images, time t = N + 1/30, N + 1/15, respectively.
Recording processing from (sec) to the memory card 9 is performed,
Although illustration is omitted, the time t is set for the third captured image.
= N + 7/60 (sec) and the recording process to the memory card 9 is performed. In addition, the first to third captured images are displayed on the liquid crystal display unit 16 immediately after the start of each recording timing.
Is displayed as a display image. That is, here, the first
The first and third photographed images are continuously recorded and displayed by skipping the second adjusted image.

Therefore, here, when acquiring the second and third photographed images, the position of the photographing lens 11 is set to
With the initial focus position (x = x10), the lens position (x = x) obtained by driving the taking lens 11 forward and backward from the initial focus position by an adjustment distance when acquiring the first and second adjusted images.
9, x11), the blurred adjustment image for determining the focus state of the taking lens 11 (for focus determination) is not recorded and displayed when the subject is not moving as shown in FIG. To do so. Also, as shown in FIG. 6, when the subject moves, the direction becomes more blurred (lens position x = x9
In this case, the blurred adjustment image for focus determination in which the taking lens 11 is driven by the adjustment distance is not recorded / displayed.

As described above, at the time of capturing a moving image, when acquiring a captured image for recording / display, the position of the photographic lens 11 is set as the initial focus position and an adjusted image not used for recording / display is acquired. At this time, by setting the taking lens 11 to a lens position which is moved back and forth from the initial focusing position by an adjustment distance, when the focusing position of the taking lens 11 has not changed, blurring for focus determination is performed. It is possible not to record and display the adjusted image that has been adjusted.
When the in-focus position is changed, it is possible to prevent the blurred adjusted image for in-focus determination, which is acquired by driving the taking lens 11 in a more blurred direction, from being recorded and displayed. It can record and display clear moving images with high accuracy.

Further, since the CCD image pickup device 30 obtains each adjusted image by lowering the resolution of each taken image as in the automatic focusing mode, the adjusted image is obtained from the CCD image pickup device 30 rather than the taken image. Image memory 7
Since the transfer time to 0 can be shortened, the focus state of the taking lens 11 can be determined in a short time, and when the subject moves when performing a focus operation that quickly follows the movement of the subject. It is possible to shorten the time for recording / displaying a blurred image.

<Second Embodiment> In the second embodiment, most of the structure is similar to that of the first embodiment, but the CCD
The number of read frames per unit time in the image sensor 30, the timing control unit 160, and the camera control unit 10
0, and the relationship between the position of the photographing lens 11 and various operation timings such as image acquisition during moving image photographing, driving of the photographing lens 11, and focus determination under the control of the driving control unit 153 is different from that of the first embodiment. . Hereinafter, differences from the first embodiment will be mainly described. In addition, about the point similar to 1st Embodiment, the same code | symbol is used and description is abbreviate | omitted.

In the above-described first embodiment, during moving image shooting, the CCD image pickup device 30 has an image signal having 1280 × 960 pixels in the main shooting mode and an image having 1280 × 80 pixels in the automatic focusing mode. The signals were read alternately and the image signals of 60 frames per second were read, but in the second embodiment, the CCD image pickup device 30 is used.
The image signal is read for 90 frames per second, and the CCD image sensor 3
0 reads out an image signal having 1280 × 960 pixels in the main photographing mode.

<Regarding Position of Shooting Lens 11 and Various Operation Timings> Next, the position of the shooting lens 11 during moving image shooting in the second embodiment and image acquisition, lens driving, and control controlled by the timing control unit 160. Various operation timings such as focus determination will be described.

Similar to FIG. 7 used in the description of the first embodiment, FIG. 8 shows image acquisition during shooting of a moving image, and shooting lens 1
1 is a diagram illustrating the relationship between various operation timings such as driving of No. 1 and focus determination and the position of the taking lens 11, the horizontal axis represents time t (sec), and the vertical direction sequentially from the top. , Image acquisition timing (exposure timing), transfer timing, lens drive timing, photographing lens position, evaluation value calculation and focus determination timing, and recording timing. The taking lens 11 in FIG.
The position of is shown in correspondence with the position of the taking lens 11 illustrated in FIGS. 5 and 6.

In FIG. 8, the time t = N (se) is calculated based on the image input while driving the taking lens 11 in the optical axis direction by a general autofocus operation.
Before acquisition of the first captured image from c), the focus position detection unit 1
54 detects the in-focus position (x = x10) of the taking lens 11 and sets it as the initial in-focus position, the taking lens 11 moves to the initial in-focus position (x = x10), and the first captured image It is assumed that the acquisition of is started.

As shown in FIG. 8, here, time t =
From N, N + 1/30 (sec), CCD image sensor 30
In, the first and second captured images are respectively acquired. Further, time t = N + 1/90, N + 1/45, N +
From 2/45 (sec), the CCD image sensor 30 acquires the first to third adjusted images, respectively. That is,
The first and second adjustment images (a plurality of adjustment images) are acquired from the acquisition of the first captured image to the start of acquisition of the second captured image, and further, the third and third adjustment images are acquired after the acquisition of the second captured image. Get the adjusted image.

Further, as shown in FIG. 8, the first and second
The photographed images and the first to third adjusted images are transferred from the CCD image pickup device 30 to the image memory 70 immediately after the respective images are acquired.

Further, here, since the adjusted image is obtained by lowering the resolution of each captured image in the CCD image pickup device 30, the adjusted image is stored in the image memory from the CCD image pickup device 30 rather than each captured image. The transfer time up to 70 can be shortened.

Further, as shown in FIG. 8, the drive controller 15
Under the control of No. 3, the taking lens 11 is driven back and forth with respect to the optical axis direction by an adjustment distance between the acquisition of each image, and the taking lens 11 is moved to the initial focus position when the first and second taken images are acquired. While driving to (x = x10), the photographing lens 11 is adjusted back and forth in the optical axis direction from the initial focus position (x = x10) when the first and second adjustment images (a plurality of adjustment images) are acquired. Drive only the distance. In other words, when the first and second adjusted images (a plurality of adjusted images) are acquired, the taking lens 11 is set to the initial focusing position (x, which is the position of the taking lens 11 when the first and second adjusted images are acquired, respectively.
= X10) to two different lens positions (x = x9, x11), which are the front and the rear.

Further, as shown in FIG. 8, the first and second
Immediately after the captured image and the first and second adjusted images are transferred to the image memory 70, the evaluation value calculation unit 152 immediately performs the first and second captured images and the first and second adjusted images. An evaluation value is calculated for each image. Then, here, time t = N + 1/18 (se
By c), the evaluation value is calculated for the second adjusted image, and the focus determination unit 155 is based on the evaluation values of the second captured image and the three images 9D including the first and second adjusted images. At, it is determined whether or not the focus position of the taking lens 11 has changed. That is, here, based on the second captured image and the first and second adjusted images (a plurality of adjusted images) acquired between the acquisition of the first and second captured images, the imaging lens 11 Can be determined.

Then, the focus determination section 155 sends the determination result to the camera control section 100 and the drive control section 153,
In response to the result, the camera control unit 100 and the drive control unit 153 control the drive of the taking lens 11.

Here, the focus determination unit 155 displays the second captured image and the first and second adjusted images which are targets when determining whether the focus position of the photographic lens 11 has changed. After the acquisition, the third captured image is acquired at the position (x = x9) of the taking lens 11. This takes some time for the focus determination unit 155 to determine the focus state of the taking lens 11, and the focus determination result does not appear until time t = N + 1/18 (sec). Assuming that the focus position has not changed, when acquiring the third adjusted image to acquire the next image for focus determination, the first image from time t = N + 1/90 (sec) is acquired. As in the case of acquiring the adjusted image, the taking lens 11 is moved to the position (x
= X9).

Then, here, as long as the in-focus position of the taking lens 11 has not changed, time t = N + 1/18
After (sec), time t = N + 1/45 to N + 1/18
Various operations are performed at timings similar to various processing timings such as image acquisition up to (sec), lens driving, and focus determination to determine the focus state of the taking lens 11.

Further, when the in-focus position of the taking lens 11 is changed, it is the same as that of the first embodiment, and therefore its explanation is omitted here.

As in the case shown in FIG. 7, the time t = N + 1/45 (sec) for the first photographed image.
The recording process from the memory card 9 to the memory card 9 is performed, and although not shown in the figure, for the second captured image, the time t = N + 1 /
Recording processing from 18 (sec) to the memory card 9 is performed. The first and second captured images are displayed on the liquid crystal display unit 16 as display images shortly after the start of the respective recording timings. That is, here, the first and second adjusted images (a plurality of adjusted images) are skipped, and the first and second captured images are continuously recorded and displayed.

Therefore, here, when acquiring the second photographed image, the position of the photographing lens 11 is set to the initial focus position (x = x10), and the first and second adjusted images (a plurality of adjusted images are adjusted). When the image is acquired, the photographing lens 11 is driven back and forth from the initial focus position by an adjustment distance to set the lens position (x = x9, x11), so that the subject is moving as shown in FIG. If not, take lens 1
Do not record or display the blurred adjustment image for focus determination of 1. Further, as shown in FIG. 6, when the subject moves, a blurred adjusted image for focus determination is recorded by driving the taking lens 11 in the more blurred direction (direction of lens position x = x9) by the adjusted distance. Do not display.

Further, in the second embodiment, the number of read frames per unit time in the CCD image pickup device 30 is increased more than in the first embodiment, so the focus determination unit 1
It is possible to obtain, in a short time, a captured image and a plurality of adjusted images required for determining the in-focus state of the photographing lens 11 at 55.

As described above, when shooting a moving image, CC
By increasing the number of read-out frames per unit time in the D image pickup device 30, it is possible to acquire a photographed image for focusing determination of the photographing lens 11 and a plurality of adjusted images in a short time. By performing the following focusing operation, it is possible to shorten the time for recording / displaying a blurred image when the subject moves.

<Third Embodiment> In the third embodiment, most of the structure is similar to that of the first embodiment, but the CCD
The number of read frames per unit time in the image sensor 30, the timing control unit 160, and the camera control unit 10
0, and the relationship between the position of the photographing lens 11 and various operation timings such as image acquisition during moving image photographing, driving of the photographing lens 11, and focus determination under the control of the driving control unit 153 is different from that of the first embodiment. . Furthermore, in the third embodiment, the focus position can be detected by the focus position detection unit 154 in parallel with the focus determination in the moving image shooting by the focus determination unit 155. Hereinafter, differences from the first embodiment will be mainly described. In addition, about the point similar to 1st Embodiment, the same code | symbol is used and description is abbreviate | omitted.

In the above-described first embodiment, during moving image shooting, the CCD image pickup device 30 has an image signal having 1280 × 960 pixels in the main shooting mode and an image signal having 1280 × 80 pixels in the automatic focusing mode. The signals are read alternately and the image signals for 60 frames are read every second. However, in the third embodiment, the number of read frames per unit time of the CCD image pickup device 30 is increased, and the image signals of the CCD image pickup device 30 are read out. Read out every 9 seconds
The CCD image pickup device 30 is set to 1 in the main photographing mode at a timing of 1 frame in 3 frames with 0 frame.
An image signal having 280 × 960 pixels is read out.

FIG. 9 shows that the photographing lens 1 moves when the subject moves.
Schematic diagram illustrating a method for determining whether or not the focus position of the taking lens 11 has changed and a method for determining the next focus position (initial focus position) when the focus position of 1 changes. Is.

In FIG. 9, similar to FIG. 6 shown in the first embodiment, the initial focus position (x = x) of the taking lens 11 shown in FIG.
A curve CLm representing the relationship between the evaluation value and the position x of the taking lens 11 in the optical axis direction when the subject is moving since the time of detecting (x10) is illustrated. It should be noted that, here, five positions (x = x8, x
9, x10, x11, x12) are equally spaced by a predetermined unit adjustment distance Δx (not shown), and a distance corresponding to an integral multiple of the unit distance is referred to as an adjustment distance.

Also in the third embodiment, as in the first embodiment, the lens is adjusted from the evaluation value (C = C10) at the initial focus position (x = x10) and the initial focus position (x = x10). Lens position (x = x
9), and the lens position (x = x11) in the direction to extend the lens by the adjustment distance from the initial focus position (x = x10).
The evaluation value (C = C9, C11) at
55 compares. And the initial focus position (x = x10)
Rather than the evaluation value at the lens position (x = x11) (C
= C11) is larger, the position of the taking lens 11 having the maximum evaluation value is the initial focus position (x = x
It is determined that it is not 10), and it is determined that the focus position of the taking lens 11 has changed. Note that, also here, similarly to the first embodiment, the direction determination for determining the direction of the position of the taking lens 11 having the maximum evaluation value is performed.

Then, as in the first embodiment, as long as the in-focus position of the taking lens 11 has not changed, the taking lens 11 is driven by the adjustment distance under the control of the drive controller 153. , The position of the taking lens 11 (x
= X9, x10, x11), the evaluation value calculation unit 152 calculates an evaluation value for the image, and the focus determination unit 155 determines that the position of the taking lens 11 having the maximum evaluation value is the initial focus position (x = x10) and the determination as to whether or not it is the same is repeated.

In addition, here, the focus determination unit 15 described above is used.
In parallel with the determination of 5, the focusing position detection unit 154, as shown in FIG. 9, the evaluation value (C = C10) at the initial focusing position (x = x10) and the initial focusing position (x = x10). ) From the lens position (x =
x8, x9) and the lens position (x = x = x10) in the direction to extend the lens from the initial focus position (x = x10).
x11, x12) evaluation value (C = C8, C9, C
11, C12), the position (x = x11) of the taking lens 11 having the maximum evaluation value is detected and determined as the next initial focus position (x = x11) of the taking lens 11. That is, five evaluation values (C = C8, C9, C10, C11,
C12), the taking lens 11 having the maximum evaluation value
If the position of can be detected, it can be determined as the next initial focus position of the taking lens 11.

When the focus position detecting section 154 determines the next initial focus position (x = x11), the drive control section 153.
Controls the drive of the taking lens 11 in the optical axis direction so as to lead to the next initial focus position (x = x11) determined by the focus position detection unit 154. Further, although not shown, when the focus determination unit 155 determines that the position of the taking lens 11 having the maximum evaluation value is not the initial focus position (x = x10), the focus position detection unit 154 If the position of the taking lens 11 having the maximum evaluation value (next initial focus position) cannot be detected, the focus determination unit 15
5, the direction of the position of the taking lens 11 having the maximum evaluation value is determined in the same manner as in the first embodiment. Therefore, based on the result of the direction determination, the general contrast is the same as in the first embodiment. System autofocus operation. Then, the photographing lens 11 moves to the next initial focus position (x =
When driven to x11), the drive control unit 153 transmits to the camera control unit 100 and the timing control unit 160 a signal indicating completion of driving of the taking lens 11 to the next initial focus position (x = x11). Further, as shown in FIG. 9 described above again, while the photographing lens 11 is driven by the adjustment distance before and after the next initial focus position under the control of the drive control unit 153, an image is acquired and the image is acquired. Based on the above, the focus determination unit 155 repeatedly determines whether or not the focus position of the taking lens 11 has changed, and the focus position detection unit 154 subsequently detects and determines the initial focus position.

By the way, in the first embodiment, since only the evaluation values for the three different positions of the photographing lens 11 can be obtained, when the focus position of the photographing lens 11 changes, the photographing with the maximum evaluation value is obtained. Although it can be determined that the position of the lens 11 is not the initial focus position (x = x10), the next initial focus position could not be detected in parallel. However, in the third embodiment, five different taking lenses 11 centering on the initial focus position are used.
Since it is possible to obtain an evaluation value for the position of, the position of the taking lens 11 having the maximum evaluation value is the initial focusing position (x = x1) when the focusing position of the taking lens 11 changes.
It is also possible to detect the next initial focus position in parallel with the determination that it is not 0).

<Regarding Position of Shooting Lens 11 and Image Acquisition Timing> Next, the position of the shooting lens 11 and the image acquisition timing during moving image shooting in the third embodiment will be described.

FIG. 10 shows the photographing lens 11 during photographing of a moving image.
The line 12L representing the relationship between the position and the time is illustrated, and the acquisition timings (exposure timings) of the captured image and the adjusted image are also indicated on the line 12L by a circle mark and a triangle mark, respectively. In FIG. 10, the horizontal axis and the vertical axis represent the position x and the time t (s
ec) is shown. Further, the position of the taking lens 11 in FIG. 10 is shown in correspondence with the position of the taking lens 11 illustrated in FIG. 9.

In addition, here, before the acquisition of the first photographed image from time t = N (sec), based on the image inputted while driving the photographing lens 11 in the optical axis direction by the autofocus operation. The focus position detection unit 154 detects the focus position (initial focus position) of the photographing lens 11, the photographing lens 11 moves to the initial focus position (x = x10), and the first captured image is acquired. It has been started.

As shown in FIG. 10, here, time t =
From N, N + 1/30, N + 1/15 (sec), the CCD image pickup device 30 respectively obtains consecutive first to third photographed images, and thereafter records them in the memory card 9, and at the same time, the liquid crystal display section. The display image based on the first to third captured images is displayed on 16. Also, the first adjustment consisting of two adjustment images acquired from time t = N + 1/90, N + 1/45 (sec) from the acquisition of the first captured image to the start of acquisition of the second captured image. After the acquisition of the image group and the acquisition of the second captured image to the start of the acquisition of the third captured image, time t = N + 2/45, N + 1/18 (s
A second adjusted image group including two adjusted images acquired from step ec) is acquired. Therefore, here, the first
And the first and third photographed images are continuously recorded and displayed by skipping the second adjusted image group.

Further, as shown in FIG. 10, the drive control unit 1
Under the control of 53, the taking lens 11 is driven back and forth with respect to the optical axis direction by an adjustment distance between the acquisition of each image, and the taking lens 11 is used at the time of obtaining the first to third taken images.
Is driven to the initial focus position (x = x10),
The photographing lens 11 when acquiring the first and second adjusted image groups
Is driven from the initial focus position (x = x10) in the optical axis direction back and forth by an adjustment distance. That is, the photographing lens 11 is moved forward and backward from the initial focus position (x = x10), which is the position of the photographing lens 11 at the time of acquiring the first to third captured images, when the first and second adjusted image groups are acquired. Two different lens positions (x8, x9, x11, x1)
It is in a state of being driven to 2).

Further, here, the second photographed image and the first photographed image
And the second adjusted image group, the evaluation value calculation unit 152 calculates an evaluation value, and based on the evaluation value, the focus determination unit 155 causes the focusing lens 11 to focus on the moving image during shooting of the moving image. In addition to determining whether the position has changed from the initial focus position, the focus position detection unit 154 determines the next focus position of the taking lens 11. That is, the focusing state of the taking lens 11 is determined and the next focusing position of the taking lens 11 is determined based on the second taken image and the first and second adjusted image groups. Note that here, the determination of the focus state of the taking lens 11 by the focus determination unit 155 is made up of the second captured image and two adjustment images acquired from time t = N + 1/45, N + 2/45. It is performed based on the three images that are displayed.

Then, the in-focus determination section 155 and the in-focus position detection section 154 provide the determination / determination result to the camera control section 10.
0 and the drive control unit 153, and in response to the result, the camera control unit 100 and the drive control unit 153 control the drive of the taking lens 11.

In addition, here, the focus determination unit 155 determines the focus state of the taking lens 11, and the focus position detecting unit 154 determines the next focus position of the taking lens 11, which is the target. After the second captured image and the first and second adjusted image groups are acquired, the third captured image is captured with the lens position x of the photographing lens 11 = x10. This will be described in the first embodiment. As described above, since it takes some time for the focus determination unit 155 to determine the focus state of the taking lens 11 and the focus position detection unit 154 to determine the next focus position of the taking lens 11,
Shooting lens 1 unnecessarily until judgment and decision result come out
1 is not driven. Therefore, in order not to blur the shot image for shooting / display until the determination result is obtained, it is assumed that the focus position of the shot lens 11 has not changed, and when the third shot image is acquired, 11 is returned to the initial focus position.

Although FIG. 10 does not describe the transfer timing, the evaluation value calculation / focus determination timing, and the recording timing shown in FIGS. 7 and 8, they are also shown in FIGS. 7 and 8. Similarly to the above, each image acquired by the CCD image sensor 30 is transferred from the CCD image sensor 30 to the image memory 70 immediately after the image is acquired. Further, when each image is transferred to the image memory 70,
Immediately, the evaluation value calculation unit 152 calculates the evaluation value for each image. Then, when the evaluation value is calculated for the image that is the subject of focus determination, the focus determination is performed immediately. Further, here, when the evaluation value is calculated for the image for which the focus position is to be detected, the focus position is immediately detected / determined. As for the captured image, immediately after the evaluation value is calculated by the evaluation value calculation unit 152, the captured image is recorded as a recorded image from the image memory 70 in the memory card 9 and is displayed as a display image in the liquid crystal display unit 16.

Therefore, here, when acquiring the second and third photographed images, the position of the photographing lens 11 is set to the initial focus position (x = x10), and the first and second adjusted image groups are obtained. At this time, the subject is moving by setting the position of the photographing lens 11 to the lens position (x = x8, x9, x11, x12) which is driven by the adjustment distance before and after the initial focus position (x = x10). When there is not, a blurred adjusted image for focus determination and for detection / determination of the focus position of the taking lens 11 (focus detection / determination) is not recorded / displayed, and as shown in FIG. When a subject moves, a blurred adjustment image for focus determination and focus detection / determination is recorded by driving the taking lens 11 in the more blurred direction (lens position x = x8, x9 direction) by the adjustment distance.
Do not display.

As described above, at the time of capturing a moving image, when the captured image for recording / display is acquired, the position of the photographing lens 11 is set as the initial focus position, and when the adjusted image not used for recording is acquired. Is set to a lens position in which the taking lens 11 is moved back and forth from the initial focusing position by an adjustment distance, so that when the focusing position of the taking lens 11 has not changed, focus determination and focus detection are performed. -It is possible not to record and display the blurred adjustment image for determination, and if the focus position of the taking lens 11 is changing, drive the taking lens 11 in the more blurred direction by the adjustment distance. Since it is possible to not record and display the blurred adjustment images for focus determination and focus detection / determination,
It is possible to record and display high-precision and clear moving images.

Furthermore, the number of read frames per unit time in the CCD image pickup device 30 is increased, and an adjusted image group is acquired between the acquisition of each captured image for recording / display, and the captured image and the captured images are acquired before and after that. By determining the next initial focus position of the taking lens 11 based on the adjusted image group, the focus operation that quickly follows the movement of the subject can be performed, so that an image that is blurred when the subject moves. The time to record and display can be shortened.

<Fourth Embodiment> In the fourth embodiment, most of the structure is similar to that of the third embodiment, but the CCD
The number of read frames per unit time in the image sensor 30, the timing control unit 160, and the camera control unit 10
The relationship between the position of the photographing lens 11 and various operation timings such as image acquisition during movie shooting, driving of the photographing lens 11, focus determination, and detection of the focus position under control of 0 and the drive control unit 153 is Different from the third embodiment. Less than,
Differences from the third embodiment will be mainly described. In addition,
The same points as those of the third embodiment will be denoted by the same reference numerals and the description thereof will be omitted.

In the third embodiment described above, during the shooting of a moving image, the reading of the image signal of the CCD image pickup device 30 is set to 90 frames per second, and the CCD image pickup device 30 sets the main image pickup mode at the timing of one frame every three frames. In the fourth embodiment, the number of read frames per unit time in the CCD image pickup device 30 is increased.
The image signal of the CCD image pickup device 30 is read out 150 times per second.
The CCD image pickup device 30 is set to 12 frames in the main photographing mode at a timing of 1 frame per 5 frames.
An image signal having 80 × 960 pixels is read out.

Also in the fourth embodiment, as shown in FIG. 9 used in the description of the third embodiment, the focus determination unit 1
In parallel with the determination of the in-focus state of the photographing lens 11 of 55 and the direction determination of determining the direction of the position of the photographing lens 11 having the maximum evaluation value, the focusing position detection unit 154 maximizes the evaluation value. The position (x = x11) of the taking lens 11 is detected,
It is determined as the next initial focus position (x = x11) of the taking lens 11.

Then, similarly to the third embodiment, when the focus position detection unit 154 determines the next initial focus position (x = x11), the drive control unit 153 causes the focus position detection unit 1
The next initial focus position (x = x1
The drive of the taking lens 11 in the optical axis direction is controlled so as to lead to 1). Although not shown, the focus determination unit 15
When it is determined by 5 that the position of the taking lens 11 having the maximum evaluation value is not the initial focus position (x = x10), the focus position detecting unit 154 determines the position of the taking lens 11 having the maximum evaluation value ( If the next initial focus position) cannot be detected, the focus determination unit 155 determines the direction of the position of the taking lens 11 having the maximum evaluation value, as in the third embodiment. Based on the direction determination result, a general contrast autofocus operation is performed as in the third embodiment. Then, when the taking lens 11 is driven to the next initial focus position (x = x11),
A signal indicating completion of driving of the taking lens 11 to the next initial focus position (x = x11) is transmitted from the drive control unit 153 to the camera control unit 100 and the timing control unit 160.
Furthermore, as shown in FIG. 9 described above again, under the control of the drive control unit 153, an image is acquired while driving the taking lens 11 before and after the initial focus position by an adjustment distance,
The focus determination unit 155 repeatedly determines whether or not the focus position of the taking lens 11 has changed based on the image, and the focus position detection unit 154 subsequently detects and determines the initial focus position.

<Regarding the Position of the Photographic Lens 11 and the Image Acquisition Timing> Next, the position of the photographic lens 11 and the image acquisition timing during moving image shooting in the fourth embodiment will be described.

FIG. 11 shows the photographing lens 11 during photographing of a moving image.
The line 13L representing the relationship between the position and the time is illustrated, and the acquisition timings of the captured image and the adjusted image are also indicated by the circles and the triangles on the line 13L. In FIG. 11, the horizontal axis and the vertical axis represent the position x and time t (sec) of the taking lens 11, respectively. Further, the position of the taking lens 11 in FIG. 11 is shown in correspondence with the position of the taking lens 11 illustrated in FIG. 9. Further, here, based on the image input while driving the taking lens 11 in the optical axis direction by the autofocus operation, the first from time t = N (sec)
Before acquiring the captured image of, the focus position detection unit 154 detects the focus position (initial focus position) of the shooting lens 11, and the shooting lens 11 moves to the initial focus position (x = x10). ,
It is assumed that acquisition of the first captured image has started.

As shown in FIG. 11, here, time t =
From the N and N + 1/30 (sec), the CCD image pickup device 30 obtains continuous first and second picked-up images, respectively, and thereafter records them in the memory card 9, and the liquid crystal display section 16 displays the first and second images. The display image is displayed based on the second captured image. Further, from the acquisition of the first captured image to the start of the acquisition of the second captured image, time t = N + 1/1
Four adjustment images (a plurality of adjustment images) are acquired from 50, N + 1/75, N + 1/50, N + 2/75. Therefore, here, the plurality of adjusted images are skipped and the first and second captured images are continuously recorded and displayed.

Further, as shown in FIG. 11, the drive control unit 1
Under the control of 53, the photographing lens 11 is driven back and forth with respect to the optical axis direction by an adjustment distance between the acquisition of each image, and the photographing lens 1 is acquired when the first and second photographed images are acquired.
1 is driven to the initial focus position (x = x10), and the photographing lens 11 is driven back and forth from the initial focus position (x = x10) in the optical axis direction by an adjustment distance when a plurality of adjusted images are acquired. It will be in a state of That is, the taking lens 11 is different at the time of acquiring a plurality of adjusted images, and is different from the initial focusing position (x = x10), which is the position of the taking lens 11 at the time of acquiring the first and second taken images, by two positions respectively. The lens is driven to the lens positions (x8, x9, x11, x12).

Further, here, the evaluation value calculation unit 152 calculates the evaluation value for the second captured image and the four adjusted images, and based on the evaluation value, the focus determination unit 155 determines whether the moving image is being captured. In addition to determining whether the focus position of the taking lens 11 has changed from the initial focus position, the focus position detecting unit 154 determines the next initial focus position of the taking lens 11. That is, the focus state of the taking lens 11 is determined based on the second taken image and the plurality of adjusted images, and the next focusing position of the taking lens 11 is determined. Note that, here, the determination of the focus state of the taking lens 11 by the focus determining unit 155 is based on the second captured image and the adjustment image acquired from the time t = N + 1/75, 1/50 (sec). Is done.

Then, the in-focus determination section 155 and the in-focus position detection section 154 provide the determination / determination result to the camera control section 10.
0 and the drive control unit 153, and in response to the result, the camera control unit 100 and the drive control unit 153 control the drive of the taking lens 11.

Although the transfer timing, the evaluation value calculation / focus determination timing, and the recording timing shown in FIGS. 7 and 8 are not described in FIG. 11, they are also shown in FIGS. 7 and 8 here. Similarly to the above, each image acquired by the CCD image sensor 30 is transferred from the CCD image sensor 30 to the image memory 70 immediately after the image is acquired. Further, when each image is transferred to the image memory 70,
Immediately, the evaluation value calculation unit 152 calculates the evaluation value for each image. Then, when the evaluation value is calculated for the image that is the subject of focus determination, the focus determination is performed immediately. Further, here, when the evaluation value is calculated for the image for which the focus position is to be detected, the focus position is immediately detected / determined. As for the captured image, immediately after the evaluation value is calculated by the evaluation value calculation unit 152, the captured image is recorded as a recorded image from the image memory 70 in the memory card 9 and is displayed as a display image in the liquid crystal display unit 16.

Therefore, here, when the second photographed image is obtained, the lens position of the photographing lens 11 is set to the initial focus position (x = x10), and when a plurality of adjusted images are obtained,
The lens position of the taking lens 11 is set to the initial focus position (x = x1
By driving the adjustment distance before and after 0), the blurred adjustment image for focus determination is not recorded and displayed when the subject is not moving, and when the subject is moving as shown in FIG. , The blurring adjusted image for focus determination is not recorded / displayed by driving the taking lens 11 in the more blurred direction (direction of lens position x = x8, x9) by the adjustment distance.

Further, in the fourth embodiment, the number of read-out frames per unit time in the CCD image pickup device 30 is increased more than in the third embodiment. Therefore, the photographing lens in the focus determination unit 155 during photographing of a moving image. It is possible to acquire the photographed image and the plurality of adjusted images required for determining the in-focus state 11 and detecting the in-focus position in the in-focus position detecting unit 154 in a short time.

As described above, the third time
The number of read-out frames per unit time in the CCD image pickup device 30 is increased as compared with the embodiment, an adjusted image group is acquired between acquisition of each captured image for recording / display, and the captured image and the captured image are acquired before that. Based on the adjusted image group and
By determining the next initial focus position of the taking lens 11, it is possible to obtain a shot image for focus determination and a focus detection / determination of the taking lens 11 and a plurality of adjusted images in a short time. Performs a focusing operation that quickly follows the movement of to record a blurred image when the subject moves.
The display time can be shortened.

Further, the adjustment image is obtained from the CCD image pickup device 30 rather than the taken image by obtaining each adjusted image with the resolution lower than that of each taken image as in the automatic focusing mode by the CCD image pickup device 30. Since the data transfer time to the memory 70 can be shortened, the next initial focusing position of the taking lens 11 can be determined in a short time, and the focusing operation that quickly follows the movement of the subject can be performed to It is possible to shorten the time for recording and displaying a blurred image when the is moved.

<Modification> The embodiment of the present invention has been described above, but the present invention is not limited to the above description.

For example, in the above-described embodiment, the focus determination and the focus detection / determination in the moving image shooting mode have been described, but the present invention is not limited to this, and continuous image recording is performed at the same timing as that of the moving image shooting. Alternatively, it may be displayed. Specifically, the present invention can be applied to a case where continuous images are displayed in an operation such as continuous AF or full-time AF in which an in-focus state of a taking lens with respect to a subject is continuously maintained.

In the second embodiment, the in-focus state of the photographing lens 11 is based on the second photographed image and the first and second adjusted images (plurality of adjusted images) acquired before that. However, the present invention is not limited to this, and based on the first captured image and the first and second adjusted images (a plurality of adjusted images) acquired thereafter, the combination of the photographic lens 11 is determined. For example, the focus state may be determined.

In the third embodiment, the adjusted image groups acquired before and after the captured image are acquired at two different photographing lens positions other than the position of the photographing lens 11 at the time of capturing the captured image. However, the present invention is not limited to this, and the adjustment image groups acquired before and after the captured image are different from each other in at least two positions other than the position of the photographing lens at the time of capturing the captured image. Anything can be used as long as it is composed of the adjustment image acquired at the position of the lens.

In the third embodiment, the next initial focus position of the photographing lens 11 is determined based on the photographed image and the adjusted image groups acquired before and after the photographed image. The present invention is not limited to this, and any one of the adjustment image groups acquired before and after the captured image is set as one adjusted image, and the taking lens 11 of the taking lens 11 is based on the adjusted image and the other adjusted image group and the captured image. The next initial focus position may be determined.

Further, in the fourth embodiment, the plurality of adjusted images acquired before the photographed image are acquired at four different positions of the photographing lens 11 other than the position of the photographing lens 11 at the time of acquiring the photographed image. Although it is composed of four adjustment images, the present invention is not limited to this, and the plurality of adjustment images acquired before the captured image are at least three positions other than the position of the photographing lens 11 at the time of capturing the captured image. What is necessary is just to be composed of the adjusted images acquired at different positions of the taking lens 11.

Further, in the fourth embodiment, based on the second photographed image and a plurality of adjusted images acquired before that,
While determining the focus state of the taking lens 11,
Although the next focus position of the taking lens 11 is determined, the present invention is not limited to this, and the taking lens 11 is determined based on the first taken image and a plurality of adjusted images acquired thereafter.
Of the focusing lens of the photographing lens 11
The next focus position may be determined.

Further, in the above-described first embodiment, the next focusing state of the taking lens 11 is determined based on the image acquired after the determination of the focusing state of the taking lens 11 is performed. However, it is not limited to this, and based on an image acquired at the time of determining the focus state of the taking lens 11 and before the determination and an image obtained after determining the focus state of the taking lens 11, the next taking lens It may be such that the focus state of 11 is determined. For example, in FIG. 7, after the in-focus state of the taking lens 11 is determined based on the three images 7D including the second taken image and the first and second adjusted images, the third taken image is taken. The focus state of the taking lens 11 may be determined based on three images including the image and the second and third adjusted images. With such a configuration, the focus state of the taking lens 11 can be determined without interruption, so that it is possible to perform a focus operation that quickly follows the movement of the subject, and the subject moves. It is possible to shorten the time for recording / displaying a blurry image.

Further, in the above-mentioned embodiment, the photographed image is recorded / displayed on the memory card 9 and the liquid crystal display unit 16 as a recorded image and a display image, respectively, and output, but the present invention is not limited to this. The captured image may be output to various devices and recording media, such as transmitting the captured image to another computer via a communication line.

Further, in the above-described embodiment, five positions (x = x8, x9, x1) of the taking lens 11 in the optical axis direction are used.
0, x11, x12) are equally spaced by a predetermined unit adjustment distance Δx, but the present invention is not limited to this, and the position of the taking lens 11 (x = x8, x) is not limited to this.
The intervals (9, x10, x11, x12) may be arbitrary intervals.

Further, in the above-described embodiment, the driving timing of the photographing lens 11 and the image acquisition timing (exposure timing) are different times, but the invention is not limited to this, and the driving of the photographing lens 11 is not limited to this. Exposure (image acquisition) may be performed during the time. In addition,
When exposure (image acquisition) is performed during the driving time of the photographing lens 11, the center of the driving range of the photographing lens 11 during exposure (image acquisition) is set to the photographing lens 1 that has been exposed (image acquired).
The position 1 is preferable. With such a configuration, driving time can be shortened, and thus a plurality of images can be captured in a short time.

Further, in the above-described embodiment, the 1280 × 960 image signals corresponding to all pixels in the main photographing mode are read out in the CCD image pickup device 30 for moving image photographing, but the present invention is not limited to this. Instead, the CCD image pickup device 30 may read image signals of 1280 × 240 in the draft mode and create image data in a format conforming to a general format such as NTSC.
With such a configuration, the CCD image pickup device 3
Since it is possible to shorten the transfer time of images from 0 to the image memory 70, it is possible to determine the focus state of the photographing lens and determine the next focus position in a short time.

The specific embodiments described above include inventions having the following configurations.

(1) The image pickup device according to claim 1, wherein the image acquisition means acquires the first and second adjusted images with a resolution lower than that of the first to third photographed images. An imaging device characterized by:

According to the invention of (1), by obtaining the adjusted image with the resolution lower than that of the photographed image, it is possible to judge the in-focus state of the photographing lens and determine the next in-focus position in a short time. Therefore, it is possible to shorten the time for outputting a blurred image when the subject moves by performing a focusing operation that quickly follows the movement of the subject.

(2) The image pickup apparatus according to claim 2 or 4, wherein the image acquisition means acquires the plurality of adjusted images with a resolution lower than that of the first and second photographed images. An imaging device characterized by:

According to the invention of (2), by obtaining the adjusted image with the resolution lower than that of the photographed image, it is possible to judge the in-focus state of the photographing lens and determine the next in-focus position in a short time. Therefore, it is possible to shorten the time for outputting a blurred image when the subject moves by performing a focusing operation that quickly follows the movement of the subject.

(3) The image pickup device according to claim 3, wherein the image acquisition means acquires the plurality of adjusted images with a resolution lower than that of the first to third photographed images. Image pickup device.

According to the invention of (3), by obtaining the adjusted image with the resolution lower than that of the photographed image, it is possible to judge the in-focus state of the photographing lens and determine the next in-focus position in a short time. Therefore, it is possible to shorten the time for outputting a blurred image when the subject moves by performing a focusing operation that quickly follows the movement of the subject.

[0150]

As described above, according to the first to fourth aspects of the present invention, the position of the taking lens is set when the taken images for output are acquired at the time of taking images that are temporally continuous. The focus position of the shooting lens has not changed by setting the shooting lens to the initial focus position and moving the shooting lens back and forth from the initial focus position when acquiring an adjusted image that is not used for output. In this case, it is possible not to output a blurred image for in-focus determination, and if the in-focus position of the shooting lens changes, drive the shooting lens in a more blurred direction to obtain Since it is possible to not output the blurred image for focus determination that is
It is possible to output a highly accurate and clear video.

According to the second aspect of the present invention, since it is possible to obtain an image for focusing determination of the taking lens in a short time at the time of capturing consecutive images, a focusing operation that quickly follows the movement of the subject. By doing so, it is possible to shorten the time for outputting a blurred image when the subject moves.

According to the third aspect of the present invention, at the time of capturing time-sequential images, an adjusted image group is acquired between the acquisition of each captured image for output and the captured image and the captured images before and after that. By determining the next focus position of the shooting lens based on the adjusted image group, the focus operation that quickly follows the movement of the subject can be performed, so a blurred image when the subject moves. The output time can be shortened.

Further, according to the invention of claim 4, when the images which are temporally continuous are taken, the adjusted image groups are respectively acquired between the acquisition of the respective taken images for output, and the taken image and the before or after the taken image are acquired. By determining the next focus position of the shooting lens based on the acquired adjustment image group, it is possible to obtain an image for focus detection / determination of the shooting lens in a short time. It is possible to shorten the time for outputting a blurred image when a subject moves by performing a focusing operation that follows quickly.

According to the fifth aspect of the present invention, the adjustment image is obtained with the resolution lower than that of the photographed image, so that the focusing state of the photographing lens and the next focusing position can be determined in a short time. Since this is possible, it is possible to perform a focusing operation that quickly follows the movement of the subject and shorten the time for outputting a blurred image when the subject moves.

[Brief description of drawings]

FIG. 1 is a perspective view showing an image pickup apparatus according to a first embodiment.

FIG. 2 is a rear view of the image pickup apparatus shown in FIG.

FIG. 3 is a block diagram showing an internal configuration of an imaging device.

FIG. 4 is a schematic diagram showing the relationship between the evaluation value and the position of the taking lens in the optical axis direction.

FIG. 5 is a schematic view illustrating a method of determining whether or not the focus position of the taking lens has changed.

FIG. 6 is a schematic view illustrating a method of determining whether or not the focus position of the taking lens has changed.

FIG. 7 is a diagram exemplifying a relationship between each operation timing such as image acquisition during moving image shooting, driving of a shooting lens, and focus determination and the position of the shooting lens.

FIG. 8 is a diagram exemplifying a relationship between each operation timing such as image acquisition during moving image shooting, driving of a shooting lens, and focus determination and the position of the shooting lens.

FIG. 9 is a schematic diagram illustrating a method for determining whether or not the focus position of the taking lens has changed and a method for determining the next focus position.

FIG. 10 is a diagram illustrating a relationship between a position of a taking lens and time during movie shooting.

FIG. 11 is a diagram exemplifying the relationship between the position of a taking lens and time during movie shooting.

FIG. 12 is a schematic diagram showing the relationship between the evaluation value and the position of the taking lens in the optical axis direction.

FIG. 13 is a schematic view illustrating a method of determining whether or not the focus position of the taking lens has changed.

FIG. 14 is a schematic diagram illustrating a method of determining whether or not the focus position of the taking lens has changed.

[Explanation of symbols]

1 Imaging device 3 Shooting function section 30 CCD image pickup device (image acquisition means) 60 resolution converter 100 camera controller 150 Optical system controller 153 Drive control unit (drive control means) 154 Focused position detection unit (detection means, determination means) 155 Focus determination unit (determination means) 160 Timing control unit

Claims (5)

[Claims] 1. An image pickup apparatus for acquiring and outputting first to third photographed images which are temporally continuous, wherein the first image is inputted based on an image inputted while driving a photographing lens in an optical axis direction. Detecting means for detecting a focus position of the photographing lens before acquiring the photographed image; a first adjusted image from after the acquisition of the first photographed image until the start of acquisition of the second photographed image; An image acquisition unit that acquires each of the second adjusted images from the acquisition of the second captured image to the start of acquisition of the third captured image, and the imaging lens when acquiring the first and second captured images. Drive control means for driving the photographing lens to the in-focus position and driving the photographing lens back and forth in the optical axis direction from the in-focus position when the first and second adjustment images are acquired; The second captured image and the first And a second adjustment image, and a determination unit that determines the in-focus state of the taking lens based on the first adjustment image and the second adjustment image, and skips the first and second adjustment images to obtain the first to third captured images. Is continuously output. 2. An imaging device for acquiring and outputting temporally continuous first and second photographed images, wherein the first image is input based on an image input while driving a photographing lens in the optical axis direction. Detection means for detecting the in-focus position of the photographing lens before acquisition of the captured image, and image acquisition for acquiring a plurality of adjustment images after the acquisition of the first captured image until the start of acquisition of the second captured image And a state in which the photographing lens is driven to the in-focus position when the first and second captured images are acquired, and the photographing lens is moved from the in-focus position to the optical axis direction when the plurality of adjusted images are acquired. Drive control means for driving the camera back and forth, and determination means for determining a focus state of the photographing lens based on the first or second photographed image and the plurality of adjusted images. Comprising the plurality of An image pickup apparatus, characterized in that the adjusted image is skipped and the first and second photographed images are continuously output. 3. An imaging device for acquiring and outputting temporally continuous first to third photographed images, wherein the first image is inputted based on an image inputted while driving a photographing lens in an optical axis direction. A detection unit that detects the in-focus position of the photographing lens before the acquisition of the captured image; and a first adjustment image that includes a plurality of adjustment images from the acquisition of the first captured image to the start of the acquisition of the second captured image. A second image including an adjusted image and a plurality of adjusted images from the acquisition of the second captured image to the start of acquisition of the third captured image.
Image acquisition means for acquiring each of the adjusted image groups, and the photographing lens is driven to the in-focus position at the time of acquiring the first and second photographed images, and the first and second adjusted images are obtained. A drive control unit that drives the photographing lens back and forth in the optical axis direction from the in-focus position when a group is acquired; the second photographed image, and the first and second adjustment image groups. Determining means for determining the next focus position of the taking lens based on the first and second adjustment image groups.
To the third captured image continuously are output. 4. An image pickup apparatus for acquiring and outputting temporally continuous first and second photographed images, wherein the first image is inputted based on an image inputted while driving a photographing lens in an optical axis direction. Detection means for detecting the in-focus position of the photographing lens before acquisition of the captured image, and image acquisition for acquiring a plurality of adjustment images after the acquisition of the first captured image until the start of acquisition of the second captured image And a state in which the photographing lens is driven to the in-focus position when the first and second captured images are acquired, and the photographing lens is moved from the in-focus position to the optical axis direction when the plurality of adjusted images are acquired. Drive control means for driving the camera back and forth, and determination means for determining the next focus position of the photographing lens based on the first or second photographed image and the plurality of adjusted images. Comprising the plurality of adjustments Skip an image, an imaging device and outputs the first and second captured image in succession. 5. The image pickup apparatus according to claim 1, wherein the image acquisition unit acquires each adjusted image with a resolution lower than that of each captured image. Imaging device.