JP2012013809A - Camera device, caf control method thereof, control program, readable storage medium, and electronic information apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To focus a camera with a natural movement by operating a lens scan without any sense of incongruity immediately after starting or setting to CAF.SOLUTION: The camera device includes: a main area for detecting a focusing state; and one or more sub areas 83 disposed around the periphery of the main area 82. When an AF evaluation value of the main area 82 is smaller than a prescribed threshold, a control unit 4 selects a sub area 83 whose AF evaluation value exceeds the prescribed threshold to be the maximum, from among the sub areas 83, as a focusing evaluation object area and conducts control to search for the focal point.

Description

  The present invention relates to a camera device having a continuous autofocus (hereinafter abbreviated as “CAF”) function for performing autofocus operation by a contrast method and performing autofocus adjustment without an instruction by half-pressing a shutter or the like, and its CAF. A control method, a control program for causing a computer to execute the CAF control method of the camera device, a computer-readable readable storage medium storing the control program, for example, a digital device using the camera device as an image input device in an imaging unit The present invention relates to an electronic information device such as a digital camera such as a video camera and a digital still camera, an image input camera such as a surveillance camera, a scanner device, a facsimile device, a television phone device, and a camera-equipped mobile phone device.

  Conventionally, there is a so-called contrast method as one of AF (autofocus) methods of a camera device. In this AF method, a subject is imaged by a solid-state imaging device such as a CCD image sensor or a CMOS image sensor, a focus evaluation value is calculated using an imaging signal in a focus area, and a focus position is determined based on the focus evaluation value. decide. The AF operation mode includes a single AF mode (SAF) in which a focusing operation is performed by half-pressing the shutter button, and a CAF mode in which the focusing operation is repeatedly performed at a predetermined interval regardless of the half-pressing operation.

  In general, in the case of a contrast-type camera device, a focusing operation called a “mountain climbing method” is employed for the CAF mode. In this hill-climbing focusing operation, the focus lens is moved by a predetermined amount, the magnitudes of the focus evaluation values before and after the movement are compared, and further moved by a predetermined amount in the direction in which the evaluation value increases, and the same processing is performed. . By repeatedly executing such processing, the focus lens is moved to a position where the focus evaluation value reaches a peak.

  On the other hand, the peak position of the focus evaluation value is not always near the focus lens position at the start of the hill-climbing focusing operation. For this reason, when the focus lens position and the peak position are largely separated, it takes time to focus, and there is a possibility that a photo opportunity will be missed.

  As a technique for avoiding this, Patent Document 1 is proposed. In Patent Document 1, when the camera apparatus is turned on, or when the sleep state is canceled and the camera is restarted, when the CAF shooting mode is set, the first focusing operation scans the entire area, and the focus is set. Search for the peak position of the evaluation value. The hill-climbing focusing operation is performed from the peak position detected by the whole area scan.

  That is, in this camera apparatus, when the camera is activated in the continuous AF shooting mode, the focusing lens is moved in one direction from one end to the other end in a predetermined area of the movable range, and the focus evaluation by the evaluation value calculating means is performed. A plurality of values are acquired, and the focusing lens is controlled to move to the peak position of the focus evaluation value calculated based on the acquired focus evaluation value.

JP 2003-295040 A

  However, in the above conventional configuration, the focus lens is in the vicinity of the peak of the focus evaluation value at the time of start-up or CAF setting, and when the whole area scan is performed in a state where the focus is in focus or almost in focus, the focus is lost. The image will be displayed on the display screen.

  In addition, even when a whole area scan is performed in an out-of-focus state, the search is performed past the peak position of the focus evaluation value, so an image that is once out of focus and then out of focus is displayed on the display screen. It may be done. These problems are particularly problematic during movie shooting. Therefore, it is not possible to focus on the target subject with a natural motion.

  The present invention solves the above-described conventional problems. A camera device that can operate a lens scan without a sense of incongruity immediately after activation or CAF setting, and can focus with a natural operation, its CAF control method, and this camera device A control program for causing a computer to execute the CAF control method, a computer-readable readable storage medium storing the control program, and a camera-equipped mobile phone device using the camera device as an image input device in an imaging unit An object is to provide electronic information equipment.

  The camera device of the present invention detects an in-focus position by moving an imaging unit that converts an optical image formed on an imaging surface into image data, and moving a focus lens to adjust the focus of the optical image. In a camera apparatus comprising a control unit that continuously performs focus adjustment to stop the focus lens at the detected focus position, a main area for detecting a focus state of the optical image, and a periphery of the main area One or more sub-areas arranged on the imaging screen, and when the control unit detects that the AF evaluation value of the main area is smaller than a predetermined threshold, The evaluation value exceeds a predetermined threshold value, and the control is performed so that the sub area where the evaluation value is the largest is selected as a focus evaluation target area and the focus position search of the focus lens is performed. It is.

  Preferably, when the control unit in the camera device of the present invention detects that the AF evaluation value of the main area exceeds a predetermined threshold during the focus position search of the focus lens, the control unit detects the alignment of the main area. Control is performed so as to perform a focus position search of the focus lens by switching from the sub-area as the focus evaluation target area.

  Further preferably, when the control unit in the camera device of the present invention detects that the in-focus position has been reached in the sub area while the AF evaluation value of the main area does not exceed a predetermined threshold value, the arrival is reached. This position is set as the in-focus position.

  Further preferably, the control unit in the camera device of the present invention determines whether or not each AF evaluation value is larger than a predetermined threshold with respect to the AF evaluation values of all of the main area and the sub area, and the main area When it is detected that the AF evaluation value of the main area is larger than a predetermined threshold value, the evaluation value of the main area is stored in the memory for CAF focus position calculation, and the AF evaluation value of the main area exceeds the predetermined threshold value. If it is detected that the sub-area is smaller, the AF evaluation value selection means for storing the evaluation value of the sub-area in the memory for CAF focus position calculation is provided.

  Further preferably, the AF evaluation value selection means in the camera apparatus of the present invention determines whether or not each AF evaluation value is greater than a predetermined threshold value for all AF evaluation values of the main area and the sub-area. Evaluation value determination means and main area selection means for saving the evaluation value of the main area in the memory for CAF focus position calculation when it is detected that the AF evaluation value of the main area is greater than a predetermined threshold value And sub-area selection means for storing the evaluation value of the sub-area in the memory for CAF focus position calculation when it is detected that the AF evaluation value of the main area is smaller than a predetermined threshold value. .

  Further preferably, the AF evaluation value selection means in the camera device of the present invention comprises: main area AF evaluation value determination means for determining whether or not the AF evaluation value of the main area is greater than a predetermined threshold; When it is detected that the AF evaluation value is larger than a predetermined threshold, the main area selection means for storing the evaluation value of the main area in the memory for CAF focus position calculation, and the AF evaluation value of the main area Sub-area AF evaluation value determining means for determining whether or not the AF evaluation value of the sub-area is larger than a predetermined threshold when it is detected that the AF evaluation value of the sub-area is smaller than a predetermined threshold; Sub-area selection means for storing the evaluation value of the sub-area in the memory for CAF focus position calculation when it is detected that the sub-area is greater than If the AF evaluation value of A is detected to be smaller than a predetermined threshold value, and a non-focused lens movement stop means for stopping the lens drive.

  Further preferably, in the preceding stage of the AF evaluation value selection means in the camera apparatus of the present invention, as the control unit, an initial position moving means for controlling the focus lens to move to an initial position, and an initial position of the focus lens Lens moving direction determining means for determining whether the moving direction from the infinity end direction or the close end direction is a moving direction from the lens, focus lens moving means for moving the focus lens in a predetermined determining direction, and the main area And AF evaluation value acquisition means for obtaining AF evaluation values of all the sub-areas.

  Further preferably, at the subsequent stage of the AF evaluation value selection means in the camera apparatus of the present invention, as the control unit, a focus position determination means for determining whether or not the focus lens is in a focus position, and the focus position A focusing lens movement stopping unit that stops driving the lens when it is determined by the determining unit to be in focus; and a focus lens determining unit that stops focusing when the focusing position determining unit determines that the lens is not focused. The sign of the fluctuation amount of the AF evaluation value is determined, the movement direction is set to the closest direction when the fluctuation amount of the AF evaluation value is positive, and the movement direction when the fluctuation amount of the AF evaluation value is smaller than positive. Lens moving direction setting means for setting the direction to infinity.

  Further preferably, in the camera device of the present invention, one main area is arranged at a center position of the photographing screen, and 1 to 8 sub areas are arranged around the main area.

  Still preferably, in a camera device according to the present invention, the sub-area is arranged further around the sub-area arranged around the main area.

  According to the CAF control method of the camera device of the present invention, an imaging unit converts an optical image formed on an imaging plane into image data, and a control unit performs focusing to adjust the focus of the optical image. In a CAF control method for a camera apparatus, the method further includes a control step of detecting a focus position by moving a lens, and continuously performing focus adjustment to stop the focus lens at the detected focus position. A main area for detecting a state and one or more sub-areas arranged around the main area are arranged on the photographing screen, and the control step is configured such that the control unit performs AF evaluation of the main area. When it is detected that the value is smaller than a predetermined threshold value, the sub-area where the AF evaluation value exceeds the predetermined threshold value and the largest sub-area is selected as the focus evaluation target area and the focus area is selected. Is intended to control so as to perform the focus position searching of the lens, the objects can be achieved.

  Preferably, in the CAF control method of the camera device of the present invention, the control step detects that the AF evaluation value of the main area exceeds a predetermined threshold during the focus lens position search of the focus lens. In this case, the main area is switched from the sub area as the focus evaluation target area, and control is performed so as to search the focus position of the focus lens.

  Still preferably, in a CAF control method for a camera apparatus according to the present invention, the control unit reaches the in-focus position in the sub-area while the control unit does not exceed the predetermined threshold AF evaluation value. If it is detected, the position that has been reached is set as the in-focus position.

  Further preferably, in the control step in the CAF control method of the camera device of the present invention, the AF evaluation value selection means is configured so that each AF evaluation value is lower than a predetermined threshold value with respect to the AF evaluation values of all the main area and the sub-area. If the AF evaluation value of the main area is detected to be larger than a predetermined threshold, the evaluation value of the main area is stored in a memory for CAF focusing position calculation, When it is detected that the AF evaluation value of the main area is smaller than a predetermined threshold value, an AF evaluation value selection step of storing the evaluation value of the sub area in the memory for CAF focus position calculation is provided.

  Further preferably, in the AF evaluation value selection step in the CAF control method of the camera device of the present invention, the AF evaluation value determination means determines that each AF evaluation value is predetermined for all the AF evaluation values of the main area and the sub-area. An AF evaluation value determining step for determining whether or not the threshold value is greater than a threshold value of the main area, and when detecting that the AF evaluation value of the main area is greater than a predetermined threshold value, the main area selecting means detects the evaluation value of the main area. Main area selection step for storing the image in the memory for CAF focus position calculation, and when detecting that the AF evaluation value of the main area is smaller than a predetermined threshold, the sub area selection means And a sub-area selection step for storing the evaluation value in the memory for CAF focus position calculation.

  Further preferably, in the AF evaluation value selection step in the CAF control method of the camera device of the present invention, the main area AF evaluation value determination means determines whether or not the AF evaluation value of the main area is larger than a predetermined threshold value. When the main area AF evaluation value determining step and detecting that the AF evaluation value of the main area is larger than a predetermined threshold value, the main area selection means uses the evaluation value of the main area for CAF focus position calculation. When the main area selection step to be stored in the memory and the AF evaluation value of the main area is detected to be smaller than a predetermined threshold, the sub-area AF evaluation value determining means determines that the AF evaluation value of the sub-area is predetermined. A sub-area AF evaluation value determining step for determining whether or not the threshold is greater than a threshold value, and the AF evaluation value of the sub-area is greater than a predetermined threshold value A sub-area selection step in which the sub-area selection means stores the evaluation value of the sub-area in the memory for CAF focus position calculation when it is detected that it is large, and the AF evaluation value of the sub-area is a predetermined threshold value If it is detected that the distance is smaller than the defocusing lens movement, the defocusing lens movement stopping means has a nonfocusing lens movement stopping step for stopping the lens driving.

  Further preferably, in the preceding stage of the AF evaluation value selection step in the CAF control method of the camera device of the present invention, as the control step, an initial position moving unit controls the focus lens to move to the initial position. A moving step, a lens moving direction determining means for determining whether the moving direction from the initial position of the focus lens is an infinity end direction or a close end direction, and a focus lens moving means, A focus lens moving step for moving the focus lens by one step in a predetermined determination direction, and an AF evaluation value acquisition means include an AF evaluation value acquisition step for obtaining AF evaluation values for all of the main area and the sub area.

  Still preferably, in a subsequent stage of the AF evaluation value selection step in the CAF control method of the camera device of the present invention, as the control step, the focus position determination means determines whether or not the focus lens is in the focus position. An in-focus position determining step; an in-focus lens movement stopping step in which the in-focus lens movement stopping means stops driving the lens when it is determined that the in-focus position determining means is in focus; and the in-focus position When the determining unit determines that the in-focus state is not in focus, the lens movement direction setting unit determines whether the AF evaluation value variation amount of the focus lens is positive or negative, and the AF evaluation value variation amount is positive. And a lens moving direction setting step for setting the moving direction to the infinity direction when the moving direction is set to the closest direction and the fluctuation amount of the AF evaluation value is smaller than positive.

  Still preferably, in a CAF control method for a camera device according to the present invention, one main area is arranged at a center position of the photographing screen, and 1 to 8 subareas are arranged around the main area. .

  Still preferably, in a CAF control method for a camera device according to the present invention, the sub-area is further disposed in the periphery of the sub-area disposed in the periphery of the main area.

  The control program according to the present invention describes a processing procedure for causing a computer to execute each step of the CAF control method for the camera apparatus according to the present invention, thereby achieving the above object.

  The readable storage medium of the present invention is a computer-readable storage medium storing the control program of the present invention, thereby achieving the above object.

  An electronic information device according to the present invention uses the camera device according to the present invention as an image input device in an imaging unit, and thereby achieves the above object.

  With the above configuration, the operation of the present invention will be described below.

  In the camera device of the present invention, an imaging means for converting an optical image formed on the imaging surface into image data, and a focus lens is moved to detect the in-focus position in order to adjust the focus of the optical image. A main unit for detecting an in-focus state of an optical image, and a periphery of the main area in a camera device including a control unit that continuously performs focus adjustment to stop the focus lens at a detected focus position One or more subareas arranged on the shooting screen and the control unit detects that the AF evaluation value of the main area is smaller than a predetermined threshold, the AF evaluation value of the subarea is Control is performed so as to perform a focus position search of the focus lens by selecting a sub-area that exceeds a predetermined threshold value and becomes the focus evaluation target area.

  As a result, when the AF evaluation value of the main area is smaller than the predetermined threshold, the control unit selects the sub area where the AF evaluation value exceeds the predetermined threshold and becomes the largest among the sub areas as the focus evaluation target area. Therefore, immediately after activation or CAF setting, the lens scan can be operated without a sense of incongruity, and the target subject P can be brought into focus by a natural operation.

  As described above, according to the present invention, the main area for detecting the in-focus state and one or more sub-areas arranged around the main area are arranged, and the control unit determines the AF evaluation value of the main area. Is smaller than the predetermined threshold value, the sub-area AF evaluation value exceeds the predetermined threshold value, and the largest sub-area is selected as the focus evaluation target area to perform focus search. It is possible to obtain a CAF search method in which the lens scan can be operated without a sense of incongruity and the target subject P can be focused with a natural operation.

It is a block diagram which shows the principal part structural example of the camera apparatus in Embodiment 1 of this invention. It is a flowchart which shows the CAF search system in the camera apparatus of FIG. FIG. 3 is a shooting screen diagram showing an example of arrangement of CAF areas set in step S3 of FIG. 2. FIG. 4 is a graph schematically showing AF evaluation values at focus lens positions when the CAF area in step S3 of FIG. 2 is arranged in FIG. 3; FIG. 3 is a flowchart showing the characteristic part of the CAF search method of the camera apparatus of FIG. It is a block diagram which shows the example of schematic structure of the electronic information device which used the camera apparatus of Embodiment 1 of this invention for the imaging part as Embodiment 2 of this invention.

  Embodiment 1 of a camera apparatus and a CAF control method thereof according to the present invention, and an embodiment of an electronic information device such as a camera-equipped mobile phone apparatus using Embodiment 1 of the camera apparatus as an image input device in an imaging unit will be described below. 2 will be described in detail with reference to the drawings.

(Embodiment 1)
FIG. 1 is a block diagram illustrating a configuration example of a main part of the camera device according to the first embodiment of the present invention.

  In FIG. 1, in the camera apparatus 10 according to the first embodiment, subject light is incident on an image sensor 2 through a focus lens 1. The focus lens 1 is driven by the motor driver 3 and adjusts the focus of the subject light image by moving in the optical axis direction.

  The motor driver 3 includes a drive mechanism that drives the focus lens 1 and a drive circuit thereof, and is controlled by a control unit (CPU) 4. Although only the focus lens 1 necessary for the description of the present invention is illustrated, a light amount adjustment mechanism such as a zoom lens, a mechanical shutter, and a diaphragm may be provided. In this case, each mechanism is driven by one or more drivers and controlled by a control unit (CPU) 4.

  The image sensor 2 has an imaging surface on which a CCD solid-state imaging device and a MOS solid-state imaging device are two-dimensionally arranged. An electrical signal corresponding to the light intensity of the subject image formed on the imaging surface is generated. The image sensor 2 includes an analog signal processing circuit, an A / D converter, and a timing generation circuit for controlling these in addition to the solid-state imaging device, but these are not shown here because they are not necessary for the description of the present invention. . The image sensor 2 outputs the captured digital signal to the digital signal processing circuit 5.

  The digital signal processing circuit 5 includes various signal processing circuits such as a gain control circuit, a luminance signal generation circuit, and a color difference signal generation circuit. In addition to this, an exposure control circuit, gamma Various image processes such as a correction circuit, a lens shading correction circuit, a white balance adjustment circuit, and an edge enhancement circuit are performed. In this exposure control circuit, the image sensor 2 is fed back so that the captured image has appropriate brightness, and the light intensity incident on the image sensor is adjusted by the exposure time.

  The control unit (CPU) 4 performs drive control on the motor driver 3, and performs control necessary for SAF drive and CAF drive, such as calculation and setting of AF area coordinates, on the digital signal processing circuit 5. . The control unit (CPU) 4 controls the entire camera device, and also performs image processing using various information such as AE and WB referred to from the digital signal processing circuit 5.

  The control unit (CPU) 4 has a volatile memory RAM 6 serving as a work memory, and temporarily stores data acquired from the digital signal processing circuit 5.

  The external setting for the camera device 10 is performed from the input device 7. This external setting includes power ON, shutter button press, menu selection, and the like. The setting from the input device 7 is transmitted to the control unit (CPU) 4 through the digital signal processing circuit 5, and the control program being executed performs processing according to the setting.

  Image data subjected to image processing by the digital signal processing circuit 5 and the control unit (CPU) 4 is output to a display device / recording medium 8 for display on an LCD or the like, or recording and storage in a nonvolatile memory such as an SD card.

  Therefore, the camera apparatus 10 according to the first embodiment includes an image sensor 2 as an imaging unit that converts an optical image formed on the imaging surface into image data, and a focus lens 1 for performing focus adjustment of the optical image. A motor driver 3 having a focus adjusting means for continuously performing focus adjustment for detecting the in-focus position by moving the focus lens 1 and stopping the focus lens 1 at the detected in-focus position, and a control unit 4 are provided. The motor driver 3 and the control unit 4 arrange a main area for detecting the in-focus state and one or more sub areas arranged around the main area, and the AF evaluation value of the main area is lower than a predetermined threshold value. If the sub-area is small, the control is performed so that the sub-AF area in which the AF evaluation value exceeds the predetermined threshold and becomes the maximum is searched as the focus evaluation target area.

  When the AF evaluation value of the main area exceeds a predetermined threshold during the focus position search, the control unit 4 performs the search by switching the main area to the focus evaluation target area. In addition, when the evaluation value of the main area does not exceed the predetermined threshold value and reaches the focus position in the sub AF area, the control unit 4 sets the position as the focus position.

  Here, the software configuration of the control unit 4 in the camera apparatus 10 according to the first embodiment will be described.

  The control unit 4 in the camera apparatus 10 according to the first embodiment includes an initial position moving unit 41 that controls the focus lens 1 to move to an initial position via the motor driver 3, and a moving direction from the initial position of the focus lens 1. A lens moving direction determining means 42 for determining whether the direction is the infinity end direction or the closest end direction, and a focus lens moving means 43 for moving the focus lens 1 in a predetermined determining direction via the motor driver 3; AF evaluation value acquisition means 44 for obtaining AF evaluation values of all of the main area and its surrounding sub-areas, and determining whether AF evaluation values of all of the main area and its surrounding sub-areas are larger than a predetermined threshold value, When it is detected that the AF evaluation value of the main area is larger than a predetermined threshold, the evaluation value of the main area is set to CAF. The AF is stored in the RAM 6 for calculating the focal position, and the sub-area evaluation value is stored in the RAM 6 for calculating the CAF focus position when it is detected that the AF evaluation value of the main area is smaller than a predetermined threshold. When the evaluation value selection means 45, the focus position determination means 46 for determining whether or not the focus lens 1 is in the focus position, and the focus position determination means 46 determine that the focus is achieved, the lens is driven. When the focusing lens movement stopping means 47 to stop and the focusing position determining means 46 determine that the in-focus state is not in focus, the sign of the AF evaluation value fluctuation amount of the focus lens 1 is determined and the AF evaluation is performed. Lens movement direction setting means 48 is provided for setting the movement direction to the closest direction when the fluctuation amount of the value is positive and setting the movement direction to the infinity direction when the fluctuation amount of the AF evaluation value is smaller than positive. And focus Continuously adjusting the focus repeatedly returns to the processing of lens moving means 43.

  The AF evaluation value selection means 45 includes a main area AF evaluation value determination means 451 for determining whether or not the AF evaluation value for the main area is greater than a predetermined threshold, and the AF evaluation value for the main area is greater than a predetermined threshold. Is detected, the main area selecting means 452 for storing the evaluation value of the main area in the memory for CAF focus position calculation, and the detection of the AF evaluation value of the main area being smaller than a predetermined threshold value. Sub-area AF evaluation value determining means 453 for determining whether or not the AF evaluation value of the sub-area is larger than a predetermined threshold, and when detecting that the AF evaluation value of the sub-area is larger than the predetermined threshold, Sub-area selection means 454 for storing the evaluation value of the area in the memory for CAF focus position calculation, and the AF evaluation value of the sub-area is smaller than a predetermined threshold value When it is detected that, and a non-focused lens movement stop means 455 for stopping the lens drive.

  On the other hand, the CAF control method of the camera apparatus 10 according to the first embodiment is based on a control program and its data read at startup from a ROM as a readable recording medium (not shown) into a RAM 6 serving as a work memory. An initial position moving step for controlling the moving means 41 to move the focus lens 1 to the initial position via the motor driver 3 and the lens moving direction determining means 42 are infinite as moving directions from the initial position of the focus lens 1. A lens moving direction determining step for determining whether the lens is in the far end direction or the near end direction, and a focus lens in which the focus lens moving unit 43 moves the focus lens 1 by one step in a predetermined determining direction via the motor driver 3. The moving step and the AF evaluation value acquisition means 44 are arranged in the main area and its surroundings. AF evaluation value acquisition step for obtaining AF evaluation values for all sub-areas, and AF evaluation value selection means 45 determine whether or not the AF evaluation values for all of the main area and its surrounding sub-areas are greater than a predetermined threshold, When it is detected that the AF evaluation value of the main area is larger than a predetermined threshold value, the evaluation value of the main area is stored in the RAM 6 for CAF focus position calculation, and the AF evaluation value of the main area is larger than the predetermined threshold value. The AF evaluation value selection step for storing the evaluation value of the sub-area in the RAM 6 for CAF focus position calculation, and the focus position determination means 46, the focus lens 1 is brought to the focus position. When the in-focus position determining step for determining whether or not the in-focus lens moving stop means 47 is determined to be in focus by the in-focus position determining means 46, the lens drive is determined. When the focus position determination unit 46 determines that the in-focus lens movement stop step and the lens movement direction setting unit 48 are not focused, the sign of the amount of change in the AF evaluation value of the focus lens 1 is positive or negative. And the moving direction is set to the closest direction when the fluctuation amount of the AF evaluation value is positive, and the moving direction is set to the infinity direction when the fluctuation amount of the AF evaluation value is smaller than positive. The moving direction setting step is executed, and the process returns to the processing of the focus lens moving unit 43 and is repeatedly performed to perform the focus adjustment continuously.

  In the AF evaluation value selection step, the main area AF evaluation value determination unit 451 determines whether the main area AF evaluation value is larger than a predetermined threshold value. A main area selection step for storing the evaluation value of the main area in the memory for CAF focus position calculation when it is detected that the AF evaluation value of the main area is greater than a predetermined threshold; and a sub-area AF evaluation value Sub-area AF evaluation value determination step for determining whether or not the AF evaluation value of the sub-area is larger than the predetermined threshold when the determination unit 453 detects that the AF evaluation value of the main area is smaller than the predetermined threshold. When the sub area selection unit 454 detects that the AF evaluation value of the sub area is larger than a predetermined threshold, The sub-area selection step for storing the evaluation value of the area in the memory for CAF in-focus position calculation and the non-focus lens movement stopping means 455 detected that the AF evaluation value of the sub-area is smaller than a predetermined threshold value. A defocusing lens movement stop step for stopping lens driving.

  A ROM (not shown) as a readable recording medium may be composed of a hard disk, a formable optical disk, a magneto-optical disk, a magnetic disk, an IC memory, and the like. This control program and its data are stored in the ROM, but this control program and its data may be downloaded to the ROM from another readable recording medium or via wireless, wired or the Internet.

  With the above configuration, the CAF control flow of the camera apparatus 10 according to the first embodiment will be described with reference to FIG.

  FIG. 2 is a flowchart showing a CAF search method in the camera apparatus 10 of FIG.

  As shown in FIG. 2, first, in step S1, settings such as camera activation, return from sleep state, and change of AF operation mode are notified from the external input device 7.

  Next, in step S2, it is determined whether or not the CAF is set. If it is in the CAF setting state (YES), the process proceeds to step S3. If not (NO), the process proceeds to the SAF operation process in step S4. The SAF operation process in step S4 means a process other than CAF, but is not necessary for the description of the present invention, so that the description thereof is omitted here.

  Subsequently, the CAF method of the present invention is established from the CAF area setting in step S3. This CAF area is composed of a sub-area that is designated by the user or prepared in advance in the center or the like as a main area, and one or more sub-areas arranged around the main area. The control unit (CPU) 4 calculates the coordinates of each area, and sets the calculated coordinates in the digital signal processing circuit 5.

  Thereafter, in step S5, the lens movement position is set in the motor driver 3 as a search end on the infinity side of the initial position. The moving position is stored in the buffer memory 61 of the RAM 6. In the next step S6, the lens moving direction is stored in the buffer memory 61 as the closest direction.

  In step S7, the AF evaluation value in the buffer memory 61 is cleared to “0” in order to initialize it. This is the initial setting process of the CAF method of the present invention.

  From the lens driving in step S8, a flow executed for each lens driving in the CAF of the present invention is shown.

  First, in step S8, the control unit 4 instructs the motor driver 3 to drive the lens in one step.

  Next, in step S9, the AF evaluation values of all the CAF areas set in step S3 are acquired from the digital signal processing circuit 5, and the acquired AF evaluation values are stored in the buffer memory 61.

  In step S10, the main AF evaluation value stored in step S9 is used to determine whether a predetermined threshold has been exceeded. The threshold value may be a fixed value adjusted in advance, or the fixed value may be normalized by the AF area size or the evaluation value.

  If the main AF evaluation value exceeds the threshold value in step S10 (YES), the process proceeds to step S13. If the main AF evaluation value does not exceed the threshold value in step S10 (NO), the process proceeds to step S11. A sub AF evaluation value is determined.

  Further, in step S11, among the sub AF evaluation values stored in step S9, the AF evaluation value of the maximum sub area is used to determine whether or not the AF evaluation value of the maximum sub area exceeds a predetermined threshold. To do. Here, the threshold value is the same as the threshold value used in step S10.

  If the sub AF evaluation value exceeds the threshold value in step S11 (YES), the process proceeds to step S13. If the sub AF evaluation value does not exceed the threshold value in step S11 (NO), the process proceeds to step S12. In S12, the lens drive is stopped as out of focus.

  In step S13, the area number of the AF evaluation value used for the determination in step S10 or step S11 is stored in the buffer memory 61. The area numbers to be stored are assigned serial numbers when the CAF area is set in step S3.

  Further, in step S14, the fluctuation amount of the AF evaluation value used for the determination in step S10 or step S11 is calculated, and the calculated fluctuation amount of the AF evaluation value is stored in the buffer memory 61. The variation amount of the stored AF evaluation value is calculated by referring to the AF evaluation value using the area number stored in step S13 as a key and subtracting the previous AF evaluation value from the current AF evaluation value of the AF area. To do.

  In step S15, it is determined whether or not the in-focus state is obtained by using the AF evaluation value, the variation amount of the AF evaluation value, the moving direction, and the moving position that have been stored so far. The method for determining the in-focus state is omitted here because it is not important for the description of the present invention.

  If it is determined in step S15 that focus is not achieved (NO), the process proceeds to step S17. If it is determined that focus is achieved in step S15 (YES), the process proceeds to step S16. Proceed to stop the lens drive.

  In step S17, the moving direction is calculated using the AF evaluation value variation stored in step S14. When the variation amount of the AF evaluation value is larger than “0” (YES), the moving direction is set as the closest direction and the process proceeds to step S18. When the variation amount of the AF evaluation value is “0” or less ( NO) sets the moving direction to the infinity direction and proceeds to the process of step S19. The moving direction set in step S18 or step S19 is stored in the buffer memory 61.

  In step S20, the control unit 4 calculates the next movement position from the current position and the movement direction, and sets the calculated next movement position in the motor driver 3. This next movement position is stored in the buffer memory 61.

  Subsequently, returning to the lens driving process of step S8, the processes of steps S8 to S20 are repeated until the in-focus state or the out-of-focus state is reached. The above is the CAF control flow of the present invention.

  FIG. 3 is a shooting screen diagram showing an example of the arrangement of the CAF area set in step S3 of FIG.

  In FIG. 3, a shooting screen 81 shows an image captured by the image sensor 2 and displayed on the display screen of the display device 8. A subject 84 photographed on the photographing screen 81 is a subject to be focused, and corresponds to a person or the like. In the shooting screen 81, an area other than the target subject 84 indicates a background, and this background is generally located behind the target subject 84. A main area 82 is arranged at the center of the subject 84 to be focused.

  In this example, the main area 82 is located at the center of the shooting screen 81. In the main area 82, only human faces are arranged here. Eight sub-areas 83 are arranged around the main area 82 at equal intervals. When the lens 1 is on the infinity side, the contrast of the main area 82 is low, and even if the focus lens 1 is moved in the closest direction, the amount of change is small and the moving direction may be correctly determined. Low.

  However, even in such a case, by arranging the sub area 83 around the main area 82, an area in which the subject 84 with higher contrast, such as the boundary of the subject 84 and the background outside the subject 84, is included in the sub area 83 can be obtained. This increases the possibility that the moving direction is correctly determined.

  FIG. 4 is a graph schematically showing the AF evaluation value at the focus lens position when the CAF area in step S3 in FIG. 2 is arranged in FIG. For simplicity, only one AF evaluation value information of the sub-area 83 is illustrated. The vertical axis in FIG. 4 indicates the amount of the AF evaluation value, and the upward direction indicates that the AF evaluation value is large. The horizontal axis in FIG. 4 indicates the focus lens position, the left side of the graph indicates the infinity side, and the right side indicates the close side.

  In FIG. 4, a vertical broken line E1 indicates an end on the infinity side where the focus lens 1 is movable during CAF, and a vertical broken line E2 indicates an end on the closest side. The solid line L1 indicates the transition state of the AF evaluation value in the main area 82, and the broken line L2 indicates the transition state of the AF evaluation value in the sub area 83 around the main area 82. A vertical broken line P2 indicates a position L2m where the evaluation value is highest in the sub-area 83, and the position in focus in the sub-area 83 is this position. Similarly, the vertical broken line P3 is a position L1m where the evaluation value is highest in the main area 82, and indicates a position in focus in the main area 82. A horizontal dotted line A1 indicates a threshold, and a vertical broken line P1 indicates a position where the AF evaluation value of the main area 82 exceeds the threshold A1 indicated by the horizontal dotted line.

  FIG. 4 shows the transition state of the AF evaluation value of each area from the vertical broken line E1 indicating the infinity end to the vertical broken line E2 indicating the closest end, but in CAF, for example, the AF of the vertical broken line P3 in focus is in focus. When the focus lens 1 moves to the position of the evaluation value L1m, it does not move closer to it.

  In this case, in the main area 82, there is almost no change in the AF evaluation value from the vertical broken line E1 indicating the end at infinity to the middle in the closest direction. In such a state, the moving direction of the focus lens 1 cannot be correctly determined, and the state where the focus is not achieved continues for a long time.

  A one-dot broken line L3 indicates a transition state of the AF evaluation value of the main area, and the control unit 4 has reached the in-focus position in the sub area 83 while the evaluation value of the main area 82 does not exceed the predetermined threshold value. In this case, the position is set as a focus position.

  However, in the invention of the first embodiment, the control unit 1 controls as follows, and the above-described conventional problems can be avoided.

  In step S8 of FIG. 2, the focus lens 1 is moved to the vertical broken line E1 indicating the end at infinity. From this point, the focus lens 1 is gradually driven in the closest direction. Since the AF evaluation value of the main area 82 falls below the horizontal dotted line A1 indicating the threshold value, NO is determined in step S10, and the AF evaluation value of the sub area 83 is determined in step S11. To determine the direction of movement. The sub-area 83 has a background or the like in the region, and the contrast on the infinity side exceeds the horizontal dotted line A1 indicating the threshold value, so YES is determined in the step S11. Further, since the fluctuation amount can be secured above a certain level, the movement direction is correctly determined by setting the movement direction as the closest direction by determining whether the fluctuation amount is positive or negative in step S17.

  Using the AF evaluation value of the sub-area 83, the processing from step S8 to step S20 is repeated, and when the focus lens 1 is moved in the closest direction, before reaching the vertical broken line P2 indicating the focus position of the sub-area 83. At the time of the vertical broken line P1, the AF evaluation value of the main area 82 exceeds the horizontal dotted line A1 indicating the threshold value. For this reason, the movement of the focus lens 1 from here to the closest direction uses the AF evaluation value of the main area 82 of the solid line L1 to move the focus lens 1 in the closest direction. This movement in the close direction is repeated up to a vertical broken line P3 indicating a position where the main area 82 is in focus.

  Here, the CAF search method of the camera apparatus 10 of FIG. 2 will be described in detail with reference to FIG. 5 as the operation principle of the first embodiment.

  FIG. 5 is a flowchart showing the characteristic part of the CAF search method of the camera apparatus 10 of FIG. 2 more simply.

  As shown in FIG. 5, first, in step S <b> 31, the control unit 4 controls the focus lens 1 to move to the initial position (infinity end) via the motor driver 3.

  Next, in step S32, the control unit 4 determines the moving direction. The control unit 4 determines whether the moving direction is the close direction from the infinity end or the opposite direction.

  Subsequently, in step S33, the control unit 4 acquires the AF evaluation values of all the set CAF areas (AF target area and peripheral area) from the digital signal processing circuit 5, and acquires the acquired AF evaluation values in the buffer memory 61 of the RAM 6. Save in.

  Further, in step S <b> 34, the control unit 4 moves the focus lens 1 by one step in a predetermined direction via the motor driver 3.

  Further, in step S35, the control unit 4 acquires the AF evaluation values of all the set CAF areas (AF target area and peripheral area) from the digital signal processing circuit 5, and stores the acquired AF evaluation values in the buffer memory 61 of the RAM 6. Save to.

  Furthermore, in step S36, the control unit 4 determines whether or not the AF target area evaluation value is larger than the threshold value. If the AF target area evaluation value is larger than the threshold value (YES), the process proceeds to step S37. If the evaluation value of the AF target area is smaller than the threshold value (NO), the process proceeds to step S38.

  Furthermore, in step S37, the control unit 4 stores the evaluation value of the AF target area (main area 82) in the buffer memory 61 of the RAM 6 for CAF focus position calculation.

  Further, in step S38, the control unit 4 stores the evaluation value of the peripheral area (subarea 83) in the buffer memory 61 of the RAM 6 for CAF focus position calculation.

  Further, in step S39, the control unit 4 determines whether or not the focus lens 1 is in an in-focus state using the AF evaluation value, the variation amount of the AF evaluation value, the moving direction, and the moving position that have been stored so far. If it is determined in step S39 that the subject is in focus (YES), the process proceeds to step S40 to stop the lens drive. If it is determined in step S39 that the subject is not in focus (NO), the process proceeds to step S41, and the moving direction of the focus lens 1 is determined in step S41. That is, the control unit 4 determines whether the AF evaluation value fluctuation amount of the focus lens 1 is positive or negative, sets the moving direction as the closest direction when the AF evaluation value fluctuation amount is positive, and changes the AF evaluation value fluctuation amount. When is smaller than positive, the moving direction is set to infinity.

  Therefore, the search method for continuous AF according to the first embodiment includes an image sensor 2 that converts an optical image formed on the imaging surface into image data, and a focus lens 1 for adjusting the focus of the optical image. In the camera device 10 including the control unit 4 that continuously moves the focus position to detect the focus position and stops the focus lens 1 at the detected focus position, and the motor driver 3 controlled thereby. A main area for detecting the in-focus state and one or more sub areas 83 arranged around the main area 82 are arranged, and the control unit 4 determines that the AF evaluation value of the main area 82 is lower than a predetermined threshold value. When it is small, the sub-area 83 in which the AF evaluation value exceeds the predetermined threshold and becomes the maximum is selected as the focus evaluation target area, and the focus search is performed. Control to.

  In this case, when the AF evaluation value of the main area 82 exceeds a predetermined threshold during the focus position search, the control unit 4 performs control so that the main area 82 is switched as the focus evaluation target area and the focus search is performed. To do.

  Further, when the AF evaluation value of the main area 82 does not exceed the predetermined threshold value and reaches the in-focus position in the sub-area 83, the control unit 4 sets the reached position as the in-focus position.

  As described above, according to the first embodiment, the main area for detecting the in-focus state and one or more sub-areas 83 arranged around the main area 82 are arranged. When the AF evaluation value is smaller than the predetermined threshold value, the sub-area 83 that has the AF evaluation value exceeding the predetermined threshold value and becomes the maximum is selected as the focus evaluation target area, and the focus search is performed. Alternatively, it is possible to obtain a CAF search method in which the lens scan can be operated without a sense of incongruity immediately after setting the CAF, and the target subject P can be focused with a natural operation.

  In the first embodiment, the camera device 10 includes the focus lens 1, the image sensor 2, the motor driver 3, the control unit (CPU) 4, the digital signal processing circuit 5, the RAM 6, and the input device 7. However, the present invention is not limited to this, and the camera device 91 that obtains a color image signal by performing predetermined signal processing on an imaging signal for each pixel that images a subject is described. The focus lens 1, the image sensor 2, the motor driver 3, a control unit (CPU) 4, a digital signal processing circuit 5, a RAM 6, and an input device 7 may be included.

  In the first embodiment, the AF evaluation value selection unit 45 includes the main area AF evaluation value determination unit 451 that determines whether the AF evaluation value of the main area is greater than a predetermined threshold value, and the AF evaluation value of the main area. Is detected to be larger than a predetermined threshold, the main area selection means 452 for storing the evaluation value of the main area in the memory for CAF focus position calculation, and the AF evaluation value of the main area is lower than the predetermined threshold. Is detected, the sub-area AF evaluation value determining means 453 determines whether or not the sub-area AF evaluation value is larger than a predetermined threshold, and the sub-area AF evaluation value is larger than the predetermined threshold. The sub-area selection means 454 for storing the evaluation value of the sub-area in the memory for CAF focus position calculation, and the AF evaluation of the sub-area. Although it has been described that the lens has the non-focus lens movement stop means 455 for stopping the lens drive when it is detected that the value is smaller than a predetermined threshold value, the AF evaluation value selection means is not limited to this. AF evaluation value determining means for determining whether or not the AF evaluation values of all areas and sub-areas are larger than a predetermined threshold value, and when the AF evaluation value of the main area is larger than a predetermined threshold value, the evaluation value of the main area is Main area selecting means for storing in the memory for calculating the CAF focus position, and when the AF evaluation value of the main area is smaller than a predetermined threshold, the evaluation value of the sub area is stored in the memory for calculating the CAF focus position. And a sub-area selection means for storing the data.

(Embodiment 2)
FIG. 6 is a block diagram illustrating a schematic configuration example of an electronic information device using the camera apparatus according to the first embodiment of the present invention as an imaging unit as the second embodiment of the present invention.

  In FIG. 6, the electronic information device 90 according to the second embodiment performs color signal images by performing predetermined signal processing on an imaging signal for each pixel in which a subject is imaged instead of the camera device 10 in the first embodiment. A camera device 91 for obtaining a signal, a memory unit 92 such as a recording medium that enables data recording after a predetermined signal processing is performed on the color image signal from the camera device 91 for recording, and a color image signal from the camera device 91 Display unit 93 such as a liquid crystal display device that can display the image on a display screen such as a liquid crystal display screen after predetermined signal processing for display, and predetermined signal processing for color image signals from this camera device 91 for communication After performing a predetermined print signal processing for printing the color image signal from the communication device 94 such as a transmission / reception device and the camera device 91 that can perform communication processing after printing And an image output unit 95 such as a printer which allows printing process. The electronic information device 90 is not limited to this, and in addition to the camera device 91, at least one of a memory unit 92, a display unit 93, a communication unit 94, and an image output unit 95 such as a printer. You may have.

  As described above, the electronic information device 90 includes, for example, a digital camera such as a digital video camera and a digital still camera, an in-vehicle camera such as a surveillance camera, a door phone camera, and an in-vehicle rear surveillance camera, and a video phone camera. An electronic device having an image input device such as an image input camera, a scanner device, a facsimile device, a camera-equipped mobile phone device, and a portable terminal device (PDA) is conceivable.

  Therefore, according to the second embodiment, based on the color image signal from the camera device 91, the image is displayed on the display screen, or is printed out by the image output unit 95 on the paper. Printing), communicating this as communication data in a wired or wireless manner, storing it in the memory unit 92 by performing predetermined data compression processing, and performing various data processing in good condition. it can.

  As mentioned above, although this invention was illustrated using preferable Embodiment 1, 2 of this invention, this invention should not be limited and limited to this Embodiment 1,2. It is understood that the scope of the present invention should be construed only by the claims. It is understood that those skilled in the art can implement an equivalent range based on the description of the present invention and the common general technical knowledge, from the description of specific preferred embodiments 1 and 2 of the present invention. Patents, patent applications, and documents cited herein should be incorporated by reference in their entirety, as if the contents themselves were specifically described herein. Understood.

  The present invention relates to a camera device having a continuous autofocus (hereinafter abbreviated as “CAF”) function for performing autofocus operation by a contrast method and performing autofocus adjustment without an instruction by half-pressing a shutter or the like, and its CAF. Control method, digital camera such as a digital video camera and a digital still camera using this camera device as an image input device in an imaging unit, an image input camera such as a surveillance camera, a scanner device, a facsimile device, a television phone device, a camera In the field of electronic information devices such as mobile phone devices with a mobile phone, a main area for detecting the in-focus state and one or more sub-areas arranged around the main area are arranged. If the AF evaluation value is smaller than the predetermined threshold, In order to select the sub-area where the AF evaluation value exceeds the predetermined threshold and becomes the largest as the focus evaluation target area and perform the focus search, the lens scan is operated without any sense of incongruity immediately after activation or CAF setting. It is possible to obtain a CAF search method capable of focusing on P with a natural operation.

DESCRIPTION OF SYMBOLS 1 Focus lens 2 Image sensor 3 Motor driver 4 Control part (CPU)
41 Initial position moving means 42 Lens moving direction determining means 43 Focus lens moving means 44 AF evaluation value acquiring means 45 AF evaluation value selecting means 451 Main area AF evaluation value determining means 452 Main area selecting means 453 Sub area AF evaluation value determining means 454 Sub-area selection means 455 Non-focus lens movement stop means 46 Focus position determination means 47 Focus lens movement stop means 48 Lens movement direction setting means 5 Digital signal processing circuit 6 RAM
7 Input device 8 Display device / Recording medium 10 Camera device 81 Shooting screen 82 Main area 83 Sub area 84 Subject L1 Solid line (transition state of AF evaluation value of main area)
L1m The position where the evaluation value is highest on the solid line L1
L2m Position where the evaluation value is highest at the broken line L2 L3 One-point broken line (transition state of AF evaluation value of the main area)
E1 Vertical broken line indicating the end at infinity E2 Vertical broken line indicating the near end P1 Vertical broken line indicating the position exceeding the horizontal dotted line A1 indicating the threshold value P2 Vertical broken line in focus at the broken line L2 Vertical broken line in focus at the solid line L1 A1 Horizontal Threshold value indicated by dotted line 90 Electronic information device 91 Camera device 92 Memory unit 93 Display unit 94 Communication unit 95 Image output unit

Claims (23)

An imaging unit that converts an optical image formed on the imaging surface into image data, and a focus lens is moved to adjust the focus of the optical image, and the focus position is detected. In a camera device including a control unit that continuously performs focus adjustment to stop the focus lens,
A main area for detecting the in-focus state of the optical image, and one or more sub-areas arranged around the main area are arranged on the photographing screen,
The control unit
When it is detected that the AF evaluation value of the main area is smaller than a predetermined threshold, the sub-area where the AF evaluation value exceeds the predetermined threshold and becomes the largest among the sub-areas is selected as the focus evaluation target area and the A camera device that controls to perform a focus position search of a focus lens.   When the control unit detects that the AF evaluation value of the main area exceeds a predetermined threshold during the focus position search of the focus lens, the control unit switches the main area from the sub area as the focus evaluation target area. The camera device according to claim 1, wherein control is performed so as to perform a focus position search of the focus lens.   The control unit, when detecting that the in-focus position has been reached in the sub-area while the AF evaluation value of the main area does not exceed a predetermined threshold value, sets the reached position as the in-focus position. The camera device according to 1. The controller is
It is determined whether or not each AF evaluation value is larger than a predetermined threshold for the AF evaluation values of all the main area and the sub-area, and it is detected that the AF evaluation value of the main area is larger than the predetermined threshold. The evaluation value of the main area is stored in the memory for CAF focus position calculation, and the evaluation value of the sub area is detected when it is detected that the AF evaluation value of the main area is smaller than a predetermined threshold value. The camera apparatus according to claim 1, further comprising an AF evaluation value selection unit that stores the image in the memory for CAF focus position calculation. The AF evaluation value selection means includes
AF evaluation value determination means for determining whether or not each AF evaluation value is greater than a predetermined threshold for all the AF evaluation values of the main area and the sub-area;
Main area selection means for storing the evaluation value of the main area in a memory for CAF focus position calculation when it is detected that the AF evaluation value of the main area is greater than a predetermined threshold;
A sub-area selection unit that stores the evaluation value of the sub area in the memory for CAF focus position calculation when it is detected that the AF evaluation value of the main area is smaller than a predetermined threshold. 5. The camera device according to 4. The AF evaluation value selection means includes
Main area AF evaluation value determining means for determining whether the AF evaluation value of the main area is larger than a predetermined threshold;
Main area selection means for storing the evaluation value of the main area in a memory for CAF focus position calculation when it is detected that the AF evaluation value of the main area is greater than a predetermined threshold;
Sub-area AF evaluation value determining means for determining whether or not the AF evaluation value of the sub-area is larger than a predetermined threshold when it is detected that the AF evaluation value of the main area is smaller than a predetermined threshold;
Sub-area selection means for storing the evaluation value of the sub-area in a memory for CAF focus position calculation when it is detected that the AF evaluation value of the sub-area is larger than a predetermined threshold;
The camera apparatus according to claim 4, further comprising a non-focus lens movement stop unit that stops the lens drive when detecting that the AF evaluation value of the sub-area is smaller than a predetermined threshold value. Before the AF evaluation value selection means, as the control unit,
An initial position moving means for controlling the focus lens to move to an initial position;
A lens moving direction determining means for determining whether the focus lens is moving from the initial position to the infinity end direction or the close end direction;
Focus lens moving means for moving the focus lens by one step in a predetermined determination direction;
The camera apparatus according to claim 4, further comprising an AF evaluation value acquisition unit that calculates AF evaluation values for all of the main area and the sub area. As the control unit after the AF evaluation value selection means,
Focusing position determination means for determining whether or not the focus lens is in a focusing position;
A focusing lens movement stop means for stopping the lens drive when it is determined that the in-focus position determination means is in focus;
When the in-focus position determining means determines that the in-focus state is not in focus, the sign of the AF evaluation value variation amount of the focus lens is determined, and the movement direction when the AF evaluation value variation amount is positive The camera apparatus according to claim 4, further comprising: a lens movement direction setting unit that sets the movement direction to an infinite direction when the movement amount of the AF evaluation value is smaller than positive.   The camera device according to claim 1, wherein one main area is arranged at a center position of the photographing screen, and 1 to 8 sub areas are arranged around the main area.   The camera device according to claim 9, wherein the sub area is also arranged around a sub area arranged around the main area. The imaging means converts the optical image formed on the imaging surface into image data, and the control unit detects the in-focus position by moving the focus lens to adjust the focus of the optical image. A CAF control method for a camera apparatus, comprising: a control step of continuously performing focus adjustment for stopping the focus lens at a detected in-focus position;
A main area for detecting the in-focus state of the optical image, and one or more sub-areas arranged around the main area are arranged on the photographing screen,
The control step includes:
When the control unit detects that the AF evaluation value of the main area is smaller than a predetermined threshold, the sub-area where the AF evaluation value exceeds the predetermined threshold and becomes the maximum among the sub areas is determined as the focus evaluation target area. CAF control method of a camera device that controls to perform a focus position search of the focus lens.   In the control step, when the control unit detects that the AF evaluation value of the main area exceeds a predetermined threshold during the focus position search of the focus lens, the main area is set as the focus evaluation target area. The CAF control method for a camera device according to claim 11, wherein control is performed such that a focus position search of the focus lens is performed by switching from the sub area.   In the control step, when the control unit detects that an in-focus position has been reached in the sub-area while the AF evaluation value of the main area does not exceed a predetermined threshold value, the control unit focuses the reached position. The CAF control method for a camera device according to claim 11, wherein the position is a position. The control step includes
The AF evaluation value selection means determines whether each AF evaluation value is larger than a predetermined threshold with respect to the AF evaluation values of all the main area and the sub-area, and the AF evaluation value of the main area is a predetermined threshold Is detected in the memory for CAF focus position calculation, and it is detected that the AF evaluation value of the main area is smaller than a predetermined threshold. 12. The camera apparatus CAF control method according to claim 11, further comprising an AF evaluation value selection step of storing the evaluation value of the sub-area in the memory for CAF focus position calculation. The AF evaluation value selection step includes:
An AF evaluation value determining means for determining whether or not each AF evaluation value is larger than a predetermined threshold for the AF evaluation values of all of the main area and the sub-area;
Main area selection step in which the main area selection means stores the evaluation value of the main area in the memory for CAF focus position calculation when it is detected that the AF evaluation value of the main area is greater than a predetermined threshold value. When,
A sub-area selection in which, when it is detected that the AF evaluation value of the main area is smaller than a predetermined threshold, the sub-area selection means stores the evaluation value of the sub-area in the memory for CAF focus position calculation The CAF control method for a camera device according to claim 14, further comprising a step. The AF evaluation value selection step includes:
A main area AF evaluation value determining means for determining whether an AF evaluation value of the main area is larger than a predetermined threshold;
Main area selection step in which the main area selection means stores the evaluation value of the main area in the memory for CAF focus position calculation when it is detected that the AF evaluation value of the main area is greater than a predetermined threshold value. When,
When it is detected that the AF evaluation value of the main area is smaller than a predetermined threshold, the sub-area AF evaluation value determination means determines whether the AF evaluation value of the sub-area is larger than a predetermined threshold. An area AF evaluation value determination step;
A sub-area selection step in which, when it is detected that the AF evaluation value of the sub-area is larger than a predetermined threshold, the sub-area selection unit stores the evaluation value of the sub-area in the memory for CAF focus position calculation When,
15. The non-focus lens movement stop unit includes a non-focus lens movement stop step of stopping lens driving when detecting that the AF evaluation value of the sub-area is smaller than a predetermined threshold value. CAF control method for the camera apparatus of the present invention. As the control step, before the AF evaluation value selection step,
An initial position moving means for controlling the initial position moving means to move the focus lens to the initial position;
A lens moving direction determining means, wherein the lens moving direction determining means determines whether the focus lens is moving from the initial position to the infinity end direction or the close end direction;
A focus lens moving means for moving the focus lens by one step in a predetermined direction;
15. The CAF control method for a camera device according to claim 14, wherein the AF evaluation value acquisition means includes an AF evaluation value acquisition step for obtaining AF evaluation values for all of the main area and the sub area. After the AF evaluation value selection step, as the control step,
An in-focus position determining means for determining whether or not the focus lens is in the in-focus position; and
A focusing lens movement stopping step in which the focusing lens movement stopping unit stops driving the lens when it is determined that the in-focus position determining unit is in focus; and
When it is determined that the in-focus position determination means is not in focus, the lens movement direction setting means determines the amount of change in the AF evaluation value of the focus lens, and the amount of change in the AF evaluation value 15. The lens moving direction setting step of setting a moving direction to a close direction when A is positive, and setting a moving direction as an infinite direction when a fluctuation amount of the AF evaluation value is smaller than positive. CAF control method for the camera apparatus of the present invention.   12. The CAF control method for a camera device according to claim 11, wherein one main area is arranged at a central position of the photographing screen, and 1 to 8 sub areas are arranged around the main area.   The CAF control method for a camera device according to claim 19, wherein the sub-area is also arranged in the vicinity of the sub-area arranged around the main area.   21. A control program in which a processing procedure for causing a computer to execute each step of the CAF control method for a camera device according to claim 11 is described.   A computer-readable storage medium storing the control program according to claim 21.   The electronic information apparatus which used the camera apparatus in any one of Claims 1-10 as an image input device for the imaging part.

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