JP5415208B2 - Imaging device - Google Patents

Description

  The present invention relates to an imaging apparatus, and more particularly to an imaging apparatus that performs phase difference detection type automatic focus adjustment (phase difference AF).

  A phase difference detection AF device used in a single-lens reflex camera or the like has a beam splitter disposed between a photographing lens and a solid-state image sensor, and the light branched by the beam splitter is used as an AF sensor for phase difference detection. The focus lens is controlled based on a detection signal indicating a phase difference detected by the AF sensor.

  Conventionally, a technique for performing phase difference AF by providing a dedicated phase difference detection pixel (AF sensor unit) in a part of a solid-state imaging device instead of providing the beam splitter and the dedicated AF sensor has been known. (Patent Document 1).

  That is, the solid-state imaging device described in Patent Document 1 relatively shifts the position of each element within a predetermined range set in advance of the solid-state imaging element and the lens (microlens) provided thereabove. The in-focus state is detected based on the comparison result between the output signal of the element shifted in the direction and the output signal of the element shifted in the other direction.

Japanese Patent No. 2959142

  However, since the solid-state imaging device described in Patent Document 1 can detect phase difference AF information only at a location where the AF sensor unit of the solid-state imaging element is provided, the subject to be focused on the AF sensor unit. If it is not located at the position, there is a problem that the subject cannot be focused.

  On the other hand, shift the angle of view so that the subject you want to focus on is positioned on the AF sensor, position the subject on the AF sensor unit, and focus the subject (after locking the focus). When the camera operation such as returning is performed, there are problems that the camera operation becomes complicated and that it takes time to shoot.

  Further, the phase difference detection pixel cannot be used as a captured image pixel, and if a large number of AF sensor units are provided in the solid-state imaging device, there is a problem that the image quality is deteriorated.

  The present invention has been made in view of such circumstances, and it is possible to expand the range in which the focus adjustment in the photographing screen can be performed while minimizing the phase difference detection pixels provided in the solid-state imaging device. It is an object of the present invention to provide an imaging device that can be used.

In order to achieve the above object, an imaging apparatus according to claim 1 includes a photographing lens, a solid-state imaging device having an AF sensor unit including pixels for phase difference detection, and camera shake detection for detecting camera shake applied to the apparatus body. And a camera shake driving optical device for correcting camera shake in the solid-state imaging device or the taking lens so as to cancel image blur due to camera shake of the apparatus main body based on a detection output of the camera shake detecting means. A correction unit; a focus control unit that reads an image signal from the solid-state image sensor; and performs focus adjustment of the photographing lens based on an image signal corresponding to a pixel of the AF sensor unit in the image signal; in the case where the AF sensor unit in the solid-state imaging device to the AF area does not exist is set to an arbitrary position of the AF sensor unit in the solid-state imaging device as an AF area that is the setting function Is characterized by comprising calculating means for calculating a, and a control means for controlling the camera shake correction means to the AF sensor unit enters the AF area based on the calculated output by said calculating means.

  That is, when there is no AF sensor unit provided in the solid-state image sensor in an arbitrary AF area where focus adjustment is desired on the shooting screen, an AF sensor is installed in the AF area using an existing camera shake correction function. The camera shake correction means is controlled so that the part can enter, and thereby the range in which focus adjustment can be performed can be expanded.

  The imaging apparatus according to claim 1, wherein the focus control unit calculates a defocus amount of the photographing lens based on an image signal corresponding to a pixel of the AF sensor unit. It includes a calculation means, and the photographing lens is driven so that the calculated defocus amount becomes zero.

  According to a third aspect of the present invention, in the imaging apparatus according to the first or second aspect, the solid-state imaging device includes a plurality of AF sensor units, and the interval between the AF sensor units can be corrected by the camera shake correction unit. The image blur correction range is not more than that. Thereby, the range in which the focus adjustment can be performed can be expanded without increasing the AF sensor unit unnecessarily.

  In the imaging device according to any one of claims 1 to 3, as shown in claim 4, a region where a specific target exists is detected based on an image signal obtained from the solid-state imaging device, and the detected region is An AF area setting means for setting as an AF area is provided.

  As the area where the specific object detected by the AF area detecting means exists, there is a specific object such as a human face, pet, flower, or the like that the photographer may want to focus on the screen. This is an area, and this area is automatically set as the AF area.

5. The image pickup apparatus according to claim 1, wherein the image display means and an image signal obtained continuously from the solid-state image sensor before photographing a main image for recording are provided. Display control means for displaying a live view image on the image display means.

  6. The image pickup apparatus according to claim 5, wherein the display control unit displays the image during a period in which the camera shake correction unit is controlled so that the AF sensor unit enters the AF area. Instead of the live view image displayed on the means, an enlarged image obtained by enlarging the live view image around the AF area is displayed on the image display means.

  That is, when the camera shake correction unit is controlled so that the AF sensor unit enters the AF area, the shooting angle of view changes and the live view image moves, but instead of the live view image, the live view image moves. By displaying an enlarged image obtained by enlarging the live view image around the AF area on the image display means, it is possible to check the AF area where focus adjustment is performed, and to feel uncomfortable such as movement of the live view image. Can be eliminated.

  The imaging apparatus according to claim 5, wherein the display control unit displays the image during a period in which the camera shake correction unit is controlled so that the AF sensor unit enters the AF area. The live view image displayed on the means is stationary.

  Accordingly, it is possible to eliminate the uncomfortable feeling that the live view image moves when controlling the camera shake correction unit that places the AF sensor unit in the AF area.

  The imaging apparatus according to any one of claims 5 to 7, wherein the display control unit has a range in which focus adjustment by the AF sensor enlarged by driving the camera shake correction unit is possible. The first index shown is displayed on the screen of the image display means. As a result, it is possible to know in advance which range of subjects in the shooting angle of view can be focused.

  The imaging apparatus according to any one of claims 5 to 8, wherein when the focus control is performed on the arbitrary AF area, the display control unit is arranged on the screen of the image display unit. A second index indicating the AF area is displayed. Thereby, it is possible to know which subject in the shooting angle of view is in focus.

  The imaging apparatus according to any one of claims 1 to 9, wherein the focus control unit includes an image signal corresponding to a pixel of the AF sensor unit until focus adjustment of the photographing lens is completed. The camera shake correction means is controlled so that the AF sensor unit enters the AF area until acquisition of the image signal is completed a plurality of times. According to this, the in-focus state can be confirmed, and the in-focus accuracy can be increased.

  11. The image pickup apparatus according to claim 1, wherein the control unit detects the camera shake when controlling the camera shake correction unit that places the AF sensor unit in the AF area. The camera shake correction means is controlled based on the detection output of the means and the calculation output of the calculation means. Better phase difference detection because camera shake correction is also performed during control of the camera shake correction unit that places the AF sensor unit in the AF area (that is, when an image signal is acquired from a pixel of the AF sensor unit). Image signals can be acquired.

  The imaging device according to any one of claims 1 to 11, wherein the control unit controls the camera shake correction unit that puts the AF sensor unit in the AF area and performs image blurring during main photographing. The control of the camera shake correction means for correcting the image is switched between when the shutter button is half-pressed and when the shutter button is fully pressed. As a result, it is possible to perform optimum control of the camera shake correction means at the time of phase difference AF and at the time of camera shake correction.

  According to the present invention, when there is no AF sensor unit provided in the solid-state imaging device in an arbitrary AF area where the focus adjustment is desired on the shooting screen, the AF is performed using the existing camera shake correction function. Since the camera shake correction unit is controlled so that the AF sensor unit enters the area, the range in which the focus adjustment can be performed is expanded while minimizing the phase difference detection pixels provided in the solid-state imaging device. Can do.

FIG. 1 is a block diagram showing an embodiment of an imaging apparatus (digital camera) according to the present invention. FIG. 2 is an enlarged view of a main part of the CCD according to the present invention. FIG. 3 is a diagram schematically showing a cross section of the CCD shown in FIG. FIG. 4 is a diagram showing the relationship between the focus state and the outputs (phase differences) of the pixels A and B for phase difference detection. FIG. 5 is a diagram showing an example of an AF sensor unit for phase difference detection provided in the CCD. FIG. 6 is a flowchart showing a processing procedure from before the photographing to image recording by the imaging apparatus (digital camera) according to the present invention. FIG. 7 is a flowchart showing a first embodiment of phase difference AF processing according to the present invention. FIG. 8 is a diagram showing a display example of a range in which focus adjustment is possible displayed on the liquid crystal monitor. FIG. 9 is a diagram illustrating another display example of the range in which the focus adjustment displayed on the liquid crystal monitor is possible. FIG. 10 is a diagram showing a second configuration example of the CCD according to the present invention. FIG. 11 is a diagram showing a third configuration example of the CCD according to the present invention. FIG. 12 is a flowchart showing a second embodiment of phase difference AF processing according to the present invention. FIG. 13 is a diagram used for explaining another display example of the through image during the period in which the camera shake detection unit is driven. FIG. 15 is a diagram showing a display example of a through image when the CCD is moved so that the AF sensor unit enters the subject detection range while the camera shake detection unit is driven. FIG. 15 is a diagram showing a fourth configuration example of the CCD according to the present invention. FIG. 16 is a diagram showing a fourth configuration example of the CCD according to the present invention. FIG. 17 is a flowchart showing a third embodiment of phase difference AF processing according to the present invention. FIG. 18 is a diagram showing the state of the CCD during normal camera shake correction and camera shake correction according to the third embodiment of the present invention. FIG. 19 is a waveform diagram showing movement of the CCD during camera shake correction and during camera shake correction according to the third embodiment of the present invention.

Hereinafter, embodiments of an imaging apparatus according to the present invention will be described with reference to the accompanying drawings.
[Overall configuration of imaging device]
FIG. 1 is a block diagram showing an embodiment of an imaging apparatus (digital camera) 10 according to the present invention.

  The digital camera 10 records captured images on a memory card 54, and the operation of the entire camera is centrally controlled by a central processing unit (CPU) 40.

  The digital camera 10 is provided with an operation unit 38 such as a shutter button, a mode dial, a playback button, a MENU / OK key, a cross key, and a BACK key. A signal from the operation unit 38 is input to the CPU 40, and the CPU 40 controls each circuit of the digital camera 10 based on the input signal. For example, lens driving control, photographing operation control, image processing control, and image data recording / reproduction are performed. Control and display control of the liquid crystal monitor 30 are performed.

  The shutter button is an operation button for inputting an instruction to start shooting, and includes a two-stage stroke type switch having an S1 switch that is turned on when half-pressed and an S2 switch that is turned on when fully pressed. The mode dial is a selection means for selecting one of an auto shooting mode for shooting a still image, a manual shooting mode, a scene position such as a person, a landscape, a night view, and a moving image mode for shooting a moving image.

  The playback button is a button for switching to a playback mode in which a captured still image or moving image is displayed on the liquid crystal monitor 30. The MENU / OK key is an operation key having both a function as a menu button for instructing to display a menu on the screen of the liquid crystal monitor 30 and a function as an OK button for instructing confirmation and execution of the selection contents. It is. The cross key is an operation unit for inputting instructions in four directions, up, down, left, and right, and functions as a button (cursor moving operation means) for selecting an item from the menu screen or instructing selection of various setting items from each menu. To do. The up / down key of the cross key functions as a zoom switch for shooting or a playback zoom switch in playback mode, and the left / right key functions as a frame advance (forward / reverse feed) button in playback mode. . The BACK key is used to delete a desired object such as a selection item, cancel an instruction content, or return to the previous operation state.

  In addition, the camera shake detection unit 39 integrates, for example, two angular velocity sensors that detect the vertical and horizontal angular velocities of the camera body and the angular velocities detected by these angular velocity sensors, respectively. And integrating means for calculating the blur angle. Detection signals indicating the vertical and horizontal camera shake angles detected by the camera shake detector 39 are applied to the CPU 40.

  In the photographing mode, image light indicating a subject is imaged on a light receiving surface of a solid-state imaging device (hereinafter referred to as “CCD”) 16 which is a CCD image sensor via a photographing lens 12 and a diaphragm 14. The photographing lens 12 is driven by a lens driving unit 32 controlled by the CPU 40, and focus control, zoom control, and the like are performed. The diaphragm 14 is composed of, for example, five diaphragm blades, and is driven by the diaphragm drive unit 33 controlled by the CPU 40. For example, the diaphragm 14 is controlled in five stages from the aperture values F2.8 to F11 in increments of 1AV.

  The CPU 40 drives the CCD 16 in the vertical and horizontal directions so as to cancel the image blur due to the camera shake of the camera body based on the detection signal indicating the vertical and horizontal shake angles of the camera body input from the camera shake detection unit 39. The camera shake correction unit 34 to be vibrated is controlled. Note that the CPU 40 also controls the camera shake correction unit 34 during phase difference AF, details of which will be described later.

  Further, the CPU 40 controls the diaphragm 14 via the diaphragm driving unit 33, and controls the charge accumulation time (shutter speed) in the CCD 16 and the image signal readout control from the CCD 16 through the CCD control unit 36.

<First CCD Configuration Example>
FIG. 2 is an enlarged view of a main part of the CCD 16 according to the present invention. The CCD 16 is a pixel for photoelectric conversion arranged in a honeycomb, and is a normal pixel that is not limited in the light receiving direction of the light beam passing through the exit pupil of the photographing lens 12 and a light beam that passes through the exit pupil of the photographing lens 12. And a pixel for detecting a phase difference that is limited in the light receiving direction. R, G, and B color filters are provided on each pixel.

  In a normal pixel, the center of the photoelectric conversion element (photodiode) PD coincides with the center of the microlens L1 provided thereabove. On the other hand, in the pixel for phase difference detection, the center of the photodiode PD is shifted from the center of the microlens L2 provided above the photodiode PD, and the microlens L2 is smaller than the microlens L1. Yes.

  In addition, as distinguished by reference signs A and B in FIG. 2, the phase difference detection pixel has a microlens L2 shifted to the right and a pixel shifted to the left with respect to the photodiode PD. And two types of pixels.

  FIG. 3 schematically shows a cross section of the CCD 16. As shown in FIG. 3, the normal pixels are condensed on the photodiode PD by the microlens L1 so as not to be limited in the light receiving direction of the light beam passing through the exit pupil of the photographing lens 12, but the phase difference detection is performed. In the pixel for use, the microlens L2 and the photodiode PD are arranged so as to be limited in the light receiving direction of the light beam passing through the exit pupil of the photographing lens 12, and in the pixel A and the pixel B, the light receiving direction of the light beam. The restriction direction is different.

  Therefore, as shown in FIGS. 4A to 4C, the outputs of the pixel A and the pixel B are out of phase or in phase with each other depending on the state of the rear pin, in-focus, and front pin. Since the phase difference between the output signals of the pixels A and B for detecting the phase difference corresponds to the defocus amount of the photographic lens 12, AF control of the photographic lens 12 can be performed by detecting this phase difference.

  The phase difference detection pixels A and B are provided in a predetermined area at the center of the CCD 16 as shown in FIG. 5, and this area is hereinafter referred to as an AF sensor section 17. As shown in FIG. 2, the AF sensor unit 17 is provided with a mixture of normal pixels and pixels A and B for phase difference detection. In FIG. 2, two pixels A and B for phase difference detection are provided. However, for example, 10 pixels are provided in the AF sensor unit 17 so that the phase difference can be detected with high accuracy. It is preferable.

  By the way, the amount of light incident on the pixels A and B for phase difference detection is about 30% of the amount of light incident on a normal pixel. Therefore, the image signals of the pixels A and B for phase difference detection are images at the time of actual photographing. It cannot be used as a signal. Therefore, the image signals at the positions of the phase difference detection pixels A and B are generated by interpolating the surrounding normal pixel image signals. Note that the image signals of the pixels A and B for phase difference detection may be amplified in accordance with the ratio of the amount of incident light with the normal pixels and used as the image signal at the time of actual photographing.

  Returning to FIG. 1, the signal charge accumulated in the CCD 16 is read out as a voltage signal corresponding to the signal charge based on the readout signal applied from the CCD controller 36. The voltage signal read from the CCD 16 is applied to the analog signal processing unit 18 where the R, G, and B signals for each pixel are sampled and held, amplified, and then applied to the A / D converter 20. The A / D converter 20 converts R, G, and B signals that are sequentially input into digital R, G, and B signals and outputs them to the image input controller 22.

  The digital signal processing unit 24 performs predetermined processing such as offset control, gain control processing including white balance correction and sensitivity correction, gamma correction processing, YC processing, etc., on the digital image signal input via the image input controller 22. Perform signal processing.

  The image data processed by the digital signal processing unit 24 is input to the VRAM 50. The VRAM 50 includes an A area and a B area each storing image data representing an image for one frame. In the VRAM 50, image data representing an image for one frame is rewritten alternately in the A area and the B area. Of the A area and B area of the VRAM 50, the written image data is read from an area other than the area where the image data is rewritten. The image data read from the VRAM 50 is encoded by the video encoder 28 and output to the liquid crystal monitor 30 provided on the back of the camera, whereby the subject image is displayed on the display screen of the liquid crystal monitor 30.

  Further, when the shutter button of the operation unit 38 is first pressed (half pressed), the AF operation and the AE operation are started. That is, of the image data output from the A / D converter 20, the image data corresponding to the AF sensor unit 17 (the output signal of the phase difference detection pixel) is taken into the phase difference detection unit 42. The phase difference detection unit 42 detects the phase difference between the image data of the pixel A and the image data of the pixel B in the AF sensor unit 17 and outputs information indicating the phase difference to the CPU 40. The CPU 40 obtains the defocus amount based on the phase difference information input from the phase difference detection unit 42, and determines the position of the focus lens in the photographing lens 12 via the lens driving unit 32 so that the defocus amount becomes zero. Control.

  The face detection unit 46 becomes operable when a button operation for turning on the face detection function is performed by the operation unit 38, and detects a human face. The face detection by the face detection unit 46 is performed by checking the correlation between the image of the target area and the face image template while moving the position of the predetermined target area in the captured image, and setting a correlation score in advance. When the threshold value is exceeded, the target area is detected as a face area. In addition, as the face detection method, a known method such as a face detection method based on edge detection or shape pattern detection, a face detection method based on hue detection, or skin color detection can be used.

  The image data output from the A / D converter 20 when the shutter button is half-pressed is taken into the AE detection unit 44. The AE detection unit 44 integrates the G signals of the entire screen, integrates the G signals with different weights in the central portion and the peripheral portion of the screen, or calculates the G signal of the face area detected by the face detection unit 46. Integration is performed and the integrated value is output to the CPU 40. The CPU 40 calculates the brightness of the subject (shooting Ev value) from the integrated value input from the AE detection unit 44, and sets the aperture value of the diaphragm 14 and the electronic shutter (shutter speed) of the CCD 16 based on this shooting Ev value. Determined according to the program diagram, controls the aperture 14 via the aperture drive unit 33 based on the determined aperture value, and charges accumulation time in the CCD 16 via the CCD control unit 36 based on the determined shutter speed To control.

  When the AE operation and the AF operation are completed and the shutter button is pressed in the second stage (full press), the image data output from the A / D converter 20 in response to the press is stored in the memory from the image input controller 22. Input to (SDRAM) 48 and temporarily stored.

  The image data temporarily stored in the memory 48 is appropriately read out by the digital signal processing unit 24, where predetermined signal processing including generation processing (YC processing) of luminance data and color difference data of the image data is performed. . The YC processed image data (YC data) is stored in the memory 48 again. Subsequently, the YC data is output to the compression / decompression processing unit 26, and a predetermined compression process such as JPEG (joint photographic experts group) is executed. The compressed YC data is output and stored again in the memory 48, and then read out by the media controller 52 and recorded in the memory card 54.

[Shooting operation]
Next, an operation at the time of shooting by the digital camera 10 having the above configuration will be described.

  FIG. 6 is a flowchart illustrating a processing procedure from before the photographing by the digital camera 10 to image recording.

  In FIG. 6, the CPU 40 determines whether or not the shutter button of the operation unit 38 has been half-pressed (S1 is ON) (step S10). If it is determined that the shutter button S1 is not turned on (in the case of “No”), the image is read from the CCD 16 in order to display a live view image (hereinafter referred to as “through image”) (step S12). If the face detection function is ON, the face detection unit 46 detects the face area from the read image (step S14). Then, a through image is displayed on the liquid crystal monitor 30 based on the read image (step S16), and the process proceeds to step S10. When face detection is performed by the face detection unit 46, a face detection frame is displayed on the through image.

  The photographer can determine the composition while looking at the through image displayed on the liquid crystal monitor 30.

  On the other hand, if it is determined in step S10 that the shutter button S1 is ON (in the case of “Yes”), the CPU 40 displays images for automatic exposure (AE) and automatic focus adjustment (phase difference AF) from the CCD 16. Read (step S18). The CPU 40 performs AE processing for determining the aperture value of the aperture 14 and the electronic shutter (shutter speed) of the CCD 16 based on the integrated value of the read image input through the AE detection unit 44 (step S20).

  Further, the CPU 40 performs a phase difference AF process (step S22).

<First Embodiment of Phase Difference AF Process>
FIG. 7 is a flowchart showing the first embodiment of the phase difference AF process in step S22.

  In FIG. 7, first, a subject detection range (AF area) arbitrarily set on the shooting screen is acquired (step S40). As the subject detection range, the face detection range detected in step S14 of FIG. 6 is used when the face detection function is ON, and when the face detection function is not ON, liquid crystal is used. A predetermined range centered on the position specified by the photographer using the cross key or touch panel on the monitor 30 is used, the face detection function is not turned on, and the AF area is not instructed by the photographer. In this case, a predetermined range at the center of the shooting screen is used.

  In addition, in a digital camera having an intelligent AF function (a function for predicting a subject that a photographer may want to focus on the screen and focusing on the predicted subject), the intelligent AF function is provided. If it is ON, the object detection range predicted by intelligent AF is used.

  Next, the CPU 40 determines whether or not the AF sensor unit 17 (see FIG. 5) exists within the subject detection range (step S42). If it exists (in the case of “Yes”), the process proceeds to step S44. If it does not exist (in the case of “No”), the process proceeds to step S46.

  In step S46, the CPU 40 calculates a difference (vector) between the AF sensor unit 17 closest to the subject detection range and the subject detection range (FIG. 5). In the example of FIG. 5, since there is only one AF sensor unit 17, a difference vector between the AF sensor unit 17 and the subject detection range is calculated.

  Subsequently, the CPU 40 controls the camera shake correction unit 34 (FIG. 1) corresponding to the calculated calculation result (vector), and moves the CCD 16 (step S48). Then, as a result of moving the CCD 16, it is determined whether or not the AF sensor unit 17 exists within the subject detection range (step S50). If it does not exist (in the case of “No”), step S46 is performed. The process from step S46 to step S50 is repeated. In this way, the AF sensor unit 17 enters the subject detection range.

  If it is determined in step S42 or step S50 that the AF sensor unit 17 exists within the subject detection range (in the case of “Yes”), the process proceeds to step S44. In step S44, an image for phase difference AF is read from the CCD 16. The phase difference detection unit 42 detects a phase difference based on an image (output signal of a phase difference detection pixel) corresponding to the AF sensor unit 17 in the read image, and information indicating the phase difference (focus) Detection information).

  The CPU 40 obtains the defocus amount based on the focus detection information input from the phase difference detection unit 42, and determines the position of the focus lens in the photographing lens 12 via the lens driving unit 32 so that the defocus amount becomes zero. Control (step S52). Thereby, phase difference AF for focusing on a subject in an arbitrary subject detection range can be performed.

  Returning to FIG. 6, in step S24, the aperture value and shutter speed determined in step S20 are held, and the position of the focus lens AF-controlled by the phase difference AF process in step S22 is held. It should be noted that when the shutter button is half-pressed, the display of the through image is stopped, and the through image is not moved when the CCD 16 is moved.

  Subsequently, the CPU 40 determines whether or not the shutter button of the operation unit 38 has been fully pressed (S2 is ON) (step S26). If it is determined that the shutter button S2 is not ON (in the case of “No”), the process proceeds to step S28, where it is determined whether or not the shutter button is half-pressed (S1 is ON). If it is half-pressed (in the case of “Yes”), the process proceeds to step S26. If it is not half-pressed (in the case of “No”), the process proceeds to step S10.

  If it is determined in step S26 that the shutter button S2 is ON (in the case of “Yes”), the main photographing is performed under the photographing conditions such as the shutter speed and the aperture value determined in the AE process in step S20. (Step S30). An image photographed by the actual photographing is read from the CCD 16 (step S32). The read image is subjected to image processing by the digital signal processing unit 24 and then subjected to compression processing by the compression / decompression processing unit 26. Is recorded in the memory card 54 (steps S34 and S36).

<Display example of adjustable focus range>
FIG. 8 is a view showing a display example of the range in which the focus adjustment can be performed displayed on the liquid crystal monitor 30, and FIGS. ing.

  As shown in FIG. 8A, during display of a through image, a fixed AF frame 60 indicating an area (AF area) in which focus adjustment can be performed without moving the CCD 16 by the camera shake correction unit 34, and camera shake correction. By moving the CCD 16 (AF sensor unit 17) by the unit 34, a frame 62 indicating a range in which focus adjustment is possible is displayed on the through image of the liquid crystal monitor 30.

  Thereby, the photographer can determine the composition while confirming the range in which the focus adjustment is possible.

  On the other hand, as shown in FIG. 8B, when the shutter button is half-pressed (S1 is ON), a specific target (for example, a person's face) that the photographer may want to focus on in the screen is displayed. , Pet, flower, etc.), and the AF frame 60 is moved to the area where the specific target exists.

  As a result, the photographer can confirm which subject is in focus.

  When a person's face is a specific target, the face detection function is turned on, and not only the person's face but also various kinds of photographs that the photographer may want to focus on the screen. When the specific target is predicted and the position is set as the AF area, the intelligent AF function is selected.

  Needless to say, when the face detection function or the intelligent AF function is OFF, the frame 62 is not displayed and the AF frame 60 does not move.

  FIG. 9 is a view showing another display example of the range in which the focus adjustment can be performed displayed on the liquid crystal monitor 30, and FIGS. 9A and 9B show a through image being displayed and a shutter button being half-pressed, respectively. Shows about. In addition, the same code | symbol is attached | subjected to the part which is common in FIG. 8, and the detailed description is abbreviate | omitted.

  In this display example, when the face detection function is ON, the face detection frame 64 and the AF frame 60 are displayed in the face area detected on the through image. The face detection frame 64 and the AF frame 60 move so as to track the face together.

  When the shutter button is half-pressed (S1 is turned on) and the face in the AF frame 60 is focused, a frame 60 'indicating the focus (a frame obtained by reducing the AF frame 60) is displayed. Note that the color of the frame may be changed instead of the small frame 60 '.

<Second and third configuration examples of CCD>
10 and 11 are diagrams showing second and third configuration examples of the CCD according to the present invention.

  In the CCD 16 of the first configuration example shown in FIG. 5, only one AF sensor unit 17 is provided at the center of the CCD 16, but the CCDs 161 and 162 of the second and third configuration examples shown in FIGS. These are different in that AF sensor portions 17 are provided at 5 and 9 locations, respectively.

  According to the CCDs 161 and 162 having the above-described configuration, the range in which the focus can be adjusted in the screen can be expanded as compared with the CCD 16 having the first configuration example. By making the range smaller than the image blur correction range in which camera shake correction can be performed by 39, the amount of movement when the AF sensor unit is moved to the specific target can be reduced.

  In the case of the CCDs 161 and 162 provided with a plurality of AF sensor units 17, in step S46 of FIG. 7, the CPU 40 determines the difference (vector) between the AF sensor unit 17 closest to the subject detection range and the subject detection range. Is calculated. Based on the calculated vector, the camera shake detection unit 39 is driven to move the CCDs 161 and 162.

<Second Embodiment of Phase Difference AF Process>
FIG. 12 is a flowchart showing a second embodiment of the phase difference AF process in step S22 shown in FIG. In addition, the same code | symbol is attached | subjected to the part which is common in the flowchart which shows 1st Embodiment of FIG. 7, and the detailed description is abbreviate | omitted.

  The second embodiment of the phase difference AF process shown in FIG. 12 is different from the first embodiment shown in FIG. 7 in that steps S60, S62, and S64 are added.

  That is, in step S52, after the focusing operation is performed by the CPU 40 based on the focus detection information, the phase difference AF image is read again from the CCD 16 and the focus detection information is acquired (step S60). Since the image after the focusing operation is performed in step S52 is a clearer image, highly accurate focus detection information can be acquired.

  It is determined whether or not focusing is completed based on the acquired focus detection information (step S62). Here, when the focus detection information indicates a phase difference of 0, it is determined that focusing has been completed.

  If focusing has not been completed (in the case of “No”), the process proceeds to step S52, the focusing operation is performed based on the latest focus detection information, and the focusing has been completed (“Yes”). In the case of "", the driving of the camera shake detection unit 39 is ended, and the CCD 16 is moved to the original position (step S64).

  13 and 14 are diagrams for explaining another display example of the through image during the period in which the camera shake detection unit 39 is driven.

  When focusing on the left person's face (subject detection range circled) as shown in FIG. 13 (A), the CCD 16 is arranged so that the AF sensor unit enters the subject detection range as shown in FIG. 13 (B). Move.

  As a result, when the through image is continuously displayed on the liquid crystal monitor 30, the angle of view of the through image is shifted by the focus detection position changing operation as shown in FIG. In order to eliminate the sense of incongruity due to the deviation of the angle of view of the live view image, the live view image is stopped when the shutter button is half-pressed. However, in this embodiment, as shown in FIG. An enlarged image obtained by enlarging the through image around the region) is displayed on the liquid crystal monitor 30.

  Thereby, it is possible to confirm which subject detection range is being focused, and to eliminate the uncomfortable feeling of moving through images.

<Fourth configuration example of CCD>
15 and 16 are views showing a fourth configuration example of the CCD according to the present invention.

  The CCDs 161 and 162 in the second and third configuration examples shown in FIGS. 10 and 11 have five and nine AF sensor sections arranged in a cross shape, but the fourth configuration shown in FIGS. The example CCD 163 has nine AF sensor portions 17 arranged in a matrix.

  FIG. 15 shows a range in which the AF sensor unit 17 in the third row and second column can detect the focus, and FIG. 16 shows a range in which the nine AF sensor units 17 can detect the focus.

  According to this, the entire photographing range by the CCD 163 can be set as a focus detectable range.

  The AF sensor unit may be arranged so as to cover a range excluding the peripheral area of the entire imaging range, not only when the entire imaging range by the CCD is covered as the focus detectable range. Further, when the AF sensor unit 17 is arranged as shown in FIG. 16, the interval between the AF sensor units 17 is set to be equal to or less than the camera shake correction movement amount.

<Third Embodiment of Phase Difference AF Process>
FIG. 17 is a flowchart showing a third embodiment of the phase difference AF process in step S22 shown in FIG. In addition, the same code | symbol is attached | subjected to the part which is common in the flowchart which shows 2nd Embodiment of FIG. 12, and the detailed description is abbreviate | omitted.

  The third embodiment of the phase difference AF process shown in FIG. 17 is different from the second embodiment shown in FIG. 12 in that steps S70, S72, and S74 are added.

  That is, in step S70, the camera shake correction function is turned on. Normally, the camera shake correction function of the camera is set to ON (the camera shake correction function can be set to OFF using a menu or the like), but in the first and second embodiments, the subject When the camera shake correction unit 34 is driven in order to put the AF sensor unit 17 in the detection range (AF region), the normal camera shake correction function is prohibited.

  In the third embodiment, the camera shake correction function is maintained in the ON state even during the phase difference AF process. When the camera shake correction unit 34 is driven for phase difference AF processing, the camera shake correction drive center position is moved by the amount of movement of the CCD 16 for placing the AF sensor unit 17 in the subject detection range (AF area). Then, the camera shake correction drive is continued (step S72).

  18A shows the state of the CCD 16 that performs only normal camera shake correction, and FIG. 18B shows the state of the CCD 16 that performs camera shake correction and phase difference AF. As shown in FIG. 18A, the normal camera shake correction is performed with the vicinity of the center of the image circle 70 as the center position of the shake correction. However, as shown in FIG. Then, the blur correction operation is performed by shifting the center position of the blur correction by the moving amount of the CCD 16 for placing the AF sensor unit 17 in the subject detection range.

  When focusing by phase difference AF is completed, the camera shake correction center is returned to the original position, and camera shake correction is subsequently performed (step S74).

  FIGS. 19A, 19B, and 19C are waveform diagrams showing movement of the CCD during conventional camera shake correction and during camera shake correction according to the third embodiment of the present invention, respectively.

  As shown in FIG. 19B, in the third embodiment of the present invention, the focus information detection period from the half-press of the shutter button (ON of S1) to the full press (ON of S2), and the center position of the CCD 16 are set. Then, the movement is shifted by the amount by which the AF sensor unit 17 is inserted into the subject detection range, and the camera shake correction operation is continued.

  Further, as shown in FIG. 19C, the focus information detection period from the half-press of the shutter button (S1 ON) to the full press (S2 ON), the amplitude of camera shake correction is suppressed, and the camera hand You may make it make it follow weakly with respect to a blur. Thereby, power consumption can be prevented from becoming excessive.

  In this way, by continuing the camera shake correction even during the focus information detection period, it is possible to capture an image without camera shake and obtain better focus detection information.

<Others>
The number and arrangement of AF sensor units provided in the solid-state imaging device are not limited to this embodiment. Further, the camera shake correction means is not limited to the one that moves the solid-state imaging device, but may be one that moves an optical member for camera shake correction in the photographing optical system.

  Further, since the amount of movement of the angle of view by the camera shake correction unit varies depending on the zoom magnification of the optical zoom, the control of the camera shake correction unit for placing the AF sensor unit in the subject detection range needs to use the zoom magnification as a control parameter. There is.

  Needless to say, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention.

  DESCRIPTION OF SYMBOLS 10 ... Imaging device (digital camera), 12 ... Shooting lens, 16, 161, 162, 163 ... Solid-state image sensor (CCD), 17 ... AF sensor part, 24 ... Digital signal processing part, 30 ... Liquid crystal monitor, 32 ... Lens Drive unit 33: Aperture drive unit 34: Camera shake correction unit 36 ... CCD control unit 38 ... Operation unit 39 ... Camera shake detection unit 40 ... Central processing unit (CPU) 42 ... Phase difference detection unit 44 ... AE detection unit, 46 ... face detection unit, 48 ... memory, 54 ... memory card, 60 ... AF frame, 62 ... frame, 64 ... face detection frame, PD ... photodiode, L1, L2 ... microlens

Claims (12)

A taking lens,
A solid-state imaging device having an AF sensor unit including pixels for phase difference detection;
Camera shake detecting means for detecting camera shake applied to the apparatus body;
Camera shake correction means for driving the optical member for camera shake correction in the solid-state imaging device or the photographing lens so as to cancel image blur due to camera shake of the apparatus main body based on the detection output of the camera shake detection means; ,
A focus control unit that reads an image signal from the solid-state imaging device and adjusts the focus of the photographing lens based on an image signal corresponding to a pixel of the AF sensor unit in the image signal;
When there is no AF sensor unit in the solid-state image sensor in the AF area arbitrarily set on the shooting screen, the positional relationship between the set AF area and the AF sensor unit in the solid-state image sensor is calculated. Calculating means for
Control means for controlling the camera shake correction means so that the AF sensor unit enters the AF area based on a calculation output by the calculation means;
An imaging apparatus comprising:   The focus control unit includes a defocus amount calculation unit that calculates a defocus amount of the photographing lens based on an image signal corresponding to a pixel of the AF sensor unit, so that the calculated defocus amount becomes zero. The imaging apparatus according to claim 1, wherein the imaging lens is driven.   The solid-state imaging device includes a plurality of AF sensor units, and an interval between the AF sensor units is equal to or less than an image blur correction range that can be corrected by the camera shake correction unit. The imaging device described.   4. An AF area setting unit that detects an area where a specific target exists based on an image signal obtained from the solid-state imaging device, and sets the detected area as the AF area. The imaging device according to any one of the above. Image display means, and display control means for displaying a live view image on the image display means based on an image signal continuously obtained from the solid-state imaging device before photographing the main image for recording. The imaging apparatus according to claim 1, wherein the imaging apparatus is characterized.   The display control means replaces the live view image displayed on the image display means with the AF area during the period when the camera shake correction means is controlled so that the AF sensor unit enters the AF area. 6. The imaging apparatus according to claim 5, wherein an enlarged image obtained by enlarging the live view image is displayed at the center on the image display means.   The display control means stops a live view image displayed on the image display means during a period in which the camera shake correction means is controlled so that the AF sensor unit enters the AF area. Item 6. The imaging device according to Item 5.   The display control unit displays on the screen of the image display unit a first index indicating a range in which focus adjustment by the AF sensor unit enlarged by driving the camera shake correction unit is possible. The imaging device according to any one of claims 5 to 7.   9. The display control unit according to claim 5, wherein when the focus control for the arbitrary AF area is performed, a second index indicating the AF area is displayed on a screen of the image display unit. The imaging device according to any one of the above.   The focus control unit acquires the image signal corresponding to the pixel of the AF sensor unit a plurality of times until the focus adjustment of the photographing lens is completed, and the AF area until the acquisition of the image signal of the plurality of times is completed. The image pickup apparatus according to claim 1, wherein the camera shake correction unit is controlled so that the AF sensor unit is inserted into the camera.   The control unit controls the camera shake correction unit based on a detection output of the camera shake detection unit and a calculation output of the calculation unit when controlling the camera shake correction unit which places the AF sensor unit in the AF area. The imaging apparatus according to claim 1, wherein:   The control means performs control of the camera shake correcting means for placing the AF sensor unit in the AF area and control of the camera shake correcting means for correcting image blur at the time of actual photographing when the shutter button is half-pressed and fully pressed. The imaging apparatus according to claim 1, wherein the imaging apparatus is switched according to time.

Images