JP5003121B2 - Focus adjustment device, focus adjustment method, and camera - Google Patents

Description

  The present invention relates to an optical apparatus and a camera having a focus adjustment function.

  As one of the automatic focus detection / adjustment (AF) systems of a camera, Patent Document 1 discloses a hybrid AF that combines both phase difference AF and contrast AF.

JP 2002-328293 A

  However, in the hybrid AF in the above-mentioned patent document, there is a problem that the distance measurement area that can be used for focus adjustment is limited as the hybrid AF, and the advantages of the two AF methods cannot be exhibited to the maximum.

The focus adjustment apparatus according to claim 1 is a phase difference formula that calculates focus detection information indicating a defocus amount and a defocus direction of a subject image in each of a plurality of first ranging areas spaced apart from each other in a shooting screen. Focus detection means, area setting means for setting the second distance measurement area at an arbitrary position in the imaging screen, and focus detection representing the focus position in the second distance measurement area set in the shooting screen Focus adjustment for performing focus adjustment control based on at least one of focus detection information of contrast type focus detection means for calculating information, focus detection information of the phase difference type focus detection means, and focus detection information of the contrast type focus detection means and control means, after setting the second distance measurement area in the area setting means, the main object keeps the main subject and identity present in the second ranging area of the set And a determination means for determining a range of the body, the focusing control means, if there is the first ranging area in the range of the main subject determined by the determination means, the phase difference focus detection means And focus adjustment control based on the focus detection information of the contrast type focus detection means, and if the first distance measuring area does not exist in the determined main subject range, the focus detection information of the contrast type focus detection means. The focus adjustment control is performed based on the above.
The focus adjustment apparatus according to claim 10 , a first focus detection unit that detects a focus adjustment state of a subject image by a phase difference AF method, an area setting unit that sets a distance measurement area at an arbitrary position in an imaging screen, ,
Focus adjustment control of an optical system using at least one of a second focus detection unit that detects a focus adjustment state by the contrast AF method in the set ranging area, and the first focus detection unit and the second focus detection unit. A focus adjustment control unit that is capable of, and a determination unit that determines a main subject range that maintains the sameness as a main subject existing in the set distance measurement area after setting the distance measurement area by the area setting unit; And the focus adjustment control unit uses the first focus detection unit and the second focus detection unit when the subject image of the first focus detection unit is included in the main subject range. Adjustment control is performed, and when the subject image of the first focus detection unit is not included in the main subject range, the focus adjustment control is performed using the second focus detection unit.

  According to the present invention, it is possible to provide a focus adjustment apparatus that uses two focus detection methods with a high degree of freedom in selecting a distance measurement area.

―First embodiment―
Hereinafter, a first embodiment of a camera with a focus adjusting device will be described with reference to the drawings. The camera of this embodiment performs focus detection / adjustment by selecting any one of phase difference AF, contrast AF, and hybrid AF using both AFs. FIG. 1 is a block diagram for explaining a main configuration of a camera according to the present invention. A lens barrel 110 having a photographic lens 120 is attached to the camera body 10 in a replaceable manner.

  In the lens barrel 110, a taking lens 120 including lens groups 120a to 120c, an AF drive motor 130, and a diaphragm member 140 are provided. A focus adjustment lens 120b is driven by the AF drive motor 130.

  Inside the camera body 10, an image sensor 20 for imaging a subject is provided. As the image sensor 20, a CCD, a CMOS, or the like is used. A quick return mirror 70 is disposed between the photographing lens 120 and the image sensor 20 to reflect the subject light that has passed through the photographing lens 120 to the viewfinder optical system. Part of the subject light passes through the semi-transmissive region of the quick return mirror 70, is reflected downward by the sub-mirror 80, is further reflected by the mirror 81, and then enters the phase difference AF detection element 100.

  The phase difference AF detection element 100, for example, receives a focus detection optical system that divides a focus detection light beam into a pair of focus detection light images and a pair of split light images, and outputs a focus detection signal corresponding to the incident light. And a pair of CCD line sensors. The focus detection signal output from the CCD line sensor is input to the control circuit 300. As will be described later, the control circuit 300 outputs a lens drive signal that drives the focus adjustment lens 120b to the in-focus position.

  The subject light reflected by the quick return mirror 70 forms an image on a finder screen 90 provided at a position optically equivalent to the image sensor 20. The subject image formed on the finder screen 90 is guided from the pentaprism 30 to the eyepiece 60 through the relay lens 50 and also formed on the light receiving surface of the photometric element 40 from the pentaprism 30. At the time of shooting, the quick return mirror 70 is moved from the optical path of the subject light to the outside of the optical path, and a subject image is formed on the image sensor 20.

  The control circuit 300 includes a CPU, ROM, RAM, and various peripheral circuits. As shown in FIG. 1, functionally, a CCD control unit 220 that controls the phase difference AF detection element 100 and an image plane displacement amount (hereinafter referred to as a defocus amount) of the imaging plane with respect to the planned focal plane. A defocus amount calculation unit 240 to calculate, a contrast detection unit 230 to calculate a focus evaluation value based on an imaging signal output from the image sensor 20, and a target position of the focus adjustment lens 120b based on the defocus amount. Or a lens target position calculation unit 250 that calculates the target position of the focus adjustment lens 120b based on the calculation result in the contrast detection unit 230, and a lens drive signal calculation that calculates an AF lens drive signal based on the AF lens target position. Part 260.

  The defocus amount calculation unit 240 performs a known defocus amount calculation based on the accumulated signal output from the CCD control unit 220. Each of the subject images formed by a pair of defocus amount detection light beams that pass through different areas of the photographing lens 120 enters the CCD line sensor. By calculating the correlation between the signals output from the pair of CCD line sensors, the relative positional deviation amount (relative interval) between the two images is calculated. The pair of subject images on the pair of CCD line sensors approach each other in a so-called front pin state in which the photographing lens 120 forms a sharp image of the subject before the planned focal plane, and conversely, the sharpness of the subject behind the planned focal plane. In the so-called rear pin state that connects the images, they move away from each other. In a focused state that connects a sharp image of the subject on the planned focal plane, the pair of subject images relatively match. In this way, by obtaining the relative positional deviation amount between the pair of subject images, the focus adjustment state of the photographing lens 120, that is, the defocus amount can be obtained.

  The contrast detection unit 230 extracts a high-frequency component from the image signal output from the image sensor 20 and performs a known focus evaluation value calculation. In a focused state in which the photographing lens 120 forms a sharp image on the image sensor 20, blurring of the edge of the subject image is minimized and the contrast is maximized, so that the focus evaluation value is also maximized.

  The lens target position calculation unit 250 calculates the lens target position based on the defocus amount calculated by the defocus amount calculation unit 240. In addition, the lens target position calculation unit 250 calculates the lens target position of the focus adjustment lens 120b such that the focus evaluation value is maximized based on the focus evaluation value calculated by the contrast detection unit 230. Based on the lens target position calculated by the lens target position calculation unit 250, the lens drive signal calculation unit 260 calculates a lens drive amount and sends a lens drive signal to the AF drive motor 130. The AF drive motor 130 moves the focus adjustment lens 120b forward and backward in the direction of the optical axis in accordance with the lens drive signal, thereby adjusting the focus adjustment state.

  The camera is provided with an AF mode changeover switch 200. By operating this, an AF selection signal is transmitted to the control circuit 300, and the AF mode can be set to “phase difference AF”. The AF mode changeover switch 200 is not limited to a mechanical switch, and may be switched on a menu screen. Further, the camera is provided with an AF switch 210 and a contrast AF area selection operation unit 270. When the AF switch 210 is turned on, a signal is transmitted to the control circuit 300, and photometry, focus detection, etc. are started. Further, by operating the contrast AF area selection operation unit 270, the contrast AF area can be set in correspondence with an arbitrary position on the shooting screen.

Next, FIG. 2 shows an example of arrangement of ranging areas.
In FIG. 2, nine phase difference AF areas 1a to 1i (hereinafter collectively referred to as “1”) are provided. A rectangular area 2 indicated by a broken line overlapping with the areas 1a to 1i represents an image on the primary image plane of a pair of line sensors for phase difference AF. Normally, when phase difference AF is used, focus detection is performed using at least one of these ranging areas. For example, based on the defocus amounts of all the ranging areas, the defocus amount corresponding to the shortest distance from the camera is adopted to perform focus detection. In this case, various methods can be adopted such as using a defocus amount of each distance measurement area while giving a large weight to the defocus amount on the short distance side. A frame 3 indicated by a bold line is a distance measurement area when using contrast AF. As described above, the contrast AF area selection unit 270 allows the photographer to manually change the contrast AF area 3 to an arbitrary position.

  In FIG. 2, as a predetermined positional relationship between the phase difference AF area 1 and the contrast AF area 3, the contrast AF area 3 partially overlaps the range 2 that can be detected by the phase difference AF area 1a or the phase difference AF sensor. An example is shown. The phase difference AF area 1 is superimposed on the subject image in the viewfinder field or on the electronic viewfinder, but the range 2 detectable by the phase difference AF sensor is not displayed.

Hereinafter, the operation of the camera having the above configuration will be described with reference to the flowchart shown in FIG. This flowchart shows a procedure performed by executing a focus detection / adjustment control program in the control circuit 300 of FIG.
In step S101 of FIG. 4, it is determined based on the AF changeover switch 200 whether or not the phase difference AF mode has been selected by the photographer's switching operation. If the phase difference AF selection signal is not received and it is determined that the phase difference AF mode is not selected, it is determined that the contrast AF mode is usable, and the process proceeds to step S102. If the phase difference AF mode is selected, the process proceeds to step S104. In step S104, focus detection is performed by a known method using phase difference AF, and focus adjustment is performed based on the detection result.

  In step S102, based on the signal from the contrast AF area selection unit 270, it is determined whether or not the position of the contrast AF area 3 for performing focus adjustment with contrast AF has been determined. If it is determined that the position of the contrast AF area 3 has been determined, the process proceeds to step S103. If it is determined that the position of the contrast AF area 3 has not been determined, the process waits until the position of the contrast AF area 3 is determined.

  In step S103, it is determined whether or not the contrast AF area 3 selected in step S102 partially overlaps the phase difference AF area 1 or the range 2 detectable by the phase difference AF sensor as shown in FIG. . If it is determined that the contrast AF area 3 partially overlaps the phase difference AF area 1 or the range 2 that can be detected by the phase difference AF sensor, the process proceeds to step S105. As shown in FIG. 3, when the contrast AF area 3 does not overlap with both the phase difference AF area 1 and the range 2 that can be detected by the phase difference AF sensor, the process proceeds to step S106, and the focus is determined by contrast AF using a known method. Make adjustments.

  In step S105, focus adjustment is performed by hybrid AF using a combination of phase difference AF and contrast AF. For example, after calculating the defocus amount by phase difference AF, only the lens driving direction is determined and contrast AF is performed. Alternatively, after calculating the defocus amount with the phase difference AF, the AF lens 120b is driven to the vicinity of the in-focus position, and then the lens is driven by the contrast formula, and then the focus evaluation value is calculated, and the lens position where the contrast value becomes the maximum Position the lens at That is, the driving direction is determined by the phase difference AF, or the rough focus lens is driven, and the AF is precisely performed by the contrast AF. Thereby, AF with high speed and high accuracy becomes possible.

As described above, according to the camera of the first embodiment, the following operational effects can be obtained.
(1) When the contrast AF area 3 can be freely set by the photographer's manual operation, if the contrast AF area 3 and the phase difference AF area 1 are in a predetermined positional relationship, focus adjustment by hybrid AF is performed. Made possible. Therefore, it is possible to perform focus adjustment by hybrid AF with an increased degree of freedom in selecting a distance measurement area.

(2) In addition, when the contrast AF area 3, the phase difference AF area 1, and the range 2 that can be detected by the phase difference AF sensor are not in a predetermined positional relationship with each other, focus adjustment is performed by contrast AF. For this reason, when the position of the contrast AF area 3 is selected, it can be operated without being aware of whether the focus adjustment is performed by contrast AF or hybrid AF, so that the operability by the photographer is improved.

-Second embodiment-
Hereinafter, the camera with a focus adjusting apparatus according to the second embodiment will be described with reference to the flowchart of FIG. In the flowchart of FIG. 5, processes having the same contents as the processes in the flowchart shown in FIG. Further, the components are the same as those of the camera with a focus adjusting device according to the first embodiment.

  FIG. 3 is a diagram showing a positional relationship between the phase difference AF area 1 and the contrast AF area 3 in the second embodiment. The arrangement of the distance measurement areas in the second embodiment is the same as that in FIG. 2 of the first embodiment. FIG. 3 shows an example in which the contrast AF area 3 does not overlap any phase difference AF area 1 or the range 2 detectable by the phase difference AF sensor but is close to the phase difference AF area 1e. Yes.

  If step S102 in FIG. 5 is affirmed, that is, if it is determined that the position of the contrast AF area 3 has been determined, the process proceeds to S107.

  In step S107, it is determined whether or not the phase difference AF area 1 and the contrast AF area 3 are close to each other as a predetermined positional relationship. For example, in the example shown in FIG. 3, it is determined that the center phase difference AF area 1e and the contrast AF area 3 are close to each other. Thus, if step S107 is affirmed, it will progress to step S105 and will perform focus adjustment by hybrid AF. If step S107 is negative, that is, if it is determined that there is no phase difference AF area 1 close to the contrast AF area 3, the process proceeds to step S106, and focus adjustment is performed with contrast AF. The determination that the phase difference AF area 1 and the contrast AF area 3 are close to each other can be performed, for example, as follows.

  As shown in FIG. 6A, when the imaging screen is divided into a plurality of blocks centered on each phase difference AF area 1 and the contrast AF area 3 is set, the phase difference is included in the block to which the contrast AF area 3 belongs. When the AF area 1 exists, it is determined that the phase difference AF area 1 and the contrast AF area 3 are close to each other. In the example of FIG. 6A, the contrast AF area 3 does not overlap with either the phase difference AF area 1e or the range 2 that can be detected by the phase difference AF sensor, but the contrast AF area 3 is located within the block in which the contrast AF area 3 is set. A phase difference AF area 1e exists. As shown in FIG. 6B, when no phase difference AF area 1 exists in the block in which the contrast AF area 3 is set, focus adjustment is performed by contrast AF. On the other hand, when the setting is made to straddle a plurality of blocks, the block to which the contrast AF area 3 belongs most may be adopted.

  Even with the camera according to the second embodiment described above, the same operational effects as the camera according to the first embodiment can be obtained, but in particular, the following operational effects can be obtained. That is, even when the contrast AF area 3 and the phase difference AF area 1 and the range 2 that can be detected by the phase difference AF sensor do not overlap each other, the hybrid method is used by using the phase difference AF area 1 in the vicinity of the contrast AF area 3. Focus detection can be performed. Therefore, since the phase difference AF area 1 can be used more effectively, the use range of the hybrid AF can be expanded.

  In the second embodiment, the shooting screen is divided into a plurality of blocks for the purpose of determining whether or not hybrid AF is possible. If the value of the smallest of the distances is equal to or smaller than a predetermined value, the closest phase difference AF area 1 may be determined as an adjacent distance measurement area.

  When dividing into blocks, a range of a predetermined distance from the center of each of the phase difference AF areas 1a to 1i may be set as the range of each block.

-Third embodiment-
In the third embodiment, the contrast AF area 3 does not overlap with any phase difference AF area 1, but any phase difference AF area is included in the range of the same subject including the contrast AF area 3. In this case, an example of performing hybrid AF will be described. Since the configuration of the camera with a focus adjustment device according to the third embodiment is the same as that of the camera with the focus adjustment device according to the first embodiment, reference is made to FIG.

  FIG. 7 is a diagram showing the positional relationship between the phase difference AF area 1 and the contrast AF area 3 in the third embodiment. The arrangement of the distance measurement areas for phase difference AF in the third embodiment is the same as that in FIG. 2 of the first embodiment. FIG. 7A shows a case where the phase difference AF area 1 a is included in the same subject range 4 including the contrast AF area 3. In such a case, hybrid AF is performed in which phase difference AF using the phase difference AF area 1a and contrast AF using the contrast AF area 3 are used in combination.

  On the other hand, FIG. 7B shows a case where any phase difference AF area 1 is not included in the same subject range 4 including the contrast AF area 3. In such a case, only contrast AF using the contrast AF area 3 is performed.

  FIG. 8 is a diagram illustrating a flowchart of processing executed by the control circuit 300 according to the third embodiment. In the flowchart of FIG. 8, processes having the same contents as the processes in the flowchart shown in FIG.

  If step S102 in FIG. 8 is affirmed, that is, if it is determined that the position of the contrast AF area 3 has been determined, the process proceeds to S110. In step S110, the range of the same subject, that is, the region of the subject that is the main subject is determined. The main subject is a subject to be subjected to AF in the contrast AF area 3. That is, the main subject is a subject at a position where the contrast AF area 3 is included, and the same subject range is a range in which the identity of the subject is maintained. For example, if the main subject is a person's face, the skin color range is the same subject range. When the face contour can be detected by edge detection, the contour range is the same subject range.

  In step S111, it is determined whether the phase difference AF area 1 and the contrast AF area 3 are in a predetermined positional relationship, that is, whether any phase difference AF area 1 exists within the same subject range. If step S111 is affirmed, the process proceeds to step S105 to perform focus adjustment by hybrid AF. When step S111 is negative, that is, when it is determined that no phase difference AF area 1 exists within the range of the same subject including the contrast AF area 3, the process proceeds to step S106, and focus adjustment is performed with contrast AF. Do.

  Even with the camera according to the third embodiment described above, the same operational effects as the camera according to the first embodiment can be obtained. In particular, even if the contrast AF area 3 and the phase difference AF area 1 do not overlap each other, if the contrast AF area 3 and the phase difference AF area 1 exist within the same subject range, Hybrid AF can be performed. As a result, AF can be performed quickly and accurately on the main subject.

-Fourth embodiment-
In the fourth embodiment, the contrast AF area 3 does not overlap with any phase difference AF area 1 and is based on the defocus distribution of the phase difference AF area existing in the vicinity of the contrast AF area 3. An example of determining the AF drive direction will be described. Since the configuration of the camera with a focus adjustment device according to the fourth embodiment is the same as that of the camera with the focus adjustment device according to the first embodiment, reference is made to FIG.

  FIG. 9 is a diagram showing a defocus distribution in the phase difference AF area 1 around the contrast AF area 3 in the fourth embodiment. The arrangement of the distance measurement areas for phase difference AF in the fourth embodiment is the same as that in FIG. 2 of the first embodiment.

  In FIG. 9A, the defocus amount of the phase difference AF area 1a around the contrast AF area 3 is −50 μm, the defocus amount of the phase difference AF area 1b is −90 μm, and the defocus amount of the phase difference AF area 1d is − It is 80 μm, and it is shown that the defocus amount directions are all the same direction. In such a case, since the driving direction for focusing the focus lens can be assumed, hybrid AF is performed, that is, the defocus amount direction of the phase difference AF area 1a, the phase difference AF area 1b, and the phase difference AF area 1d. Based on the above, hybrid AF is performed in which the driving direction of the focus lens is determined, and then contrast AF is performed based on the contrast AF area 3 while driving the focus lens in that direction.

  On the other hand, FIG. 9B shows that the defocus amount in the phase difference AF area 1a around the contrast AF area 3 is −30 μm, the defocus amount in the phase difference AF area 1b is 60 μm, and the defocus amount in the phase difference AF area 1d. −20 μm, and the directions of the defocus amounts are not always the same. In such a case, since it is difficult to determine the driving direction of the focus lens based on the distance measurement data of the phase difference AF area 1, only normal contrast AF is performed based on the contrast AF area 3.

  FIG. 10 is a diagram illustrating a flowchart of processing executed by the control circuit 300 according to the fourth embodiment. In the flowchart of FIG. 10, processes having the same contents as the processes in the flowchart shown in FIG.

  When step S102 of FIG. 10 is affirmed, that is, when it is determined that the position of the contrast AF area 3 has been determined, the process proceeds to S120. In step S120, it is determined whether there is a phase difference AF area 1 close to the contrast AF area 3. If step S120 is positive, the process proceeds to step S121. In step S121, it is determined whether there are a plurality of phase difference AF areas 1 close to the contrast AF area 3. That is, it is determined how many phase difference AF areas 1 are within a predetermined range from the contrast AF area 3.

  If it is determined in step S121 that there are a plurality, the process proceeds to step S122, in which it is determined whether all the detected defocus directions are the same direction. If it is determined in step S122 that all the defocus directions detected in the plurality of phase difference AF areas 1 are the same, the process proceeds to step S105 and the above-described hybrid AF is performed. If it is determined in step S121 that only one phase difference AF area 1 is close, the process proceeds to step S105 and the above-described hybrid AF is performed.

  In step S105, when it is determined in step S122 that the defocus directions detected in the plurality of phase difference AF areas 1 are all the same direction, the focus lens is based on the defocus amounts of the plurality of phase difference AF areas 1. Hybrid AF is performed in which contrast AF is performed while driving the focus lens in that direction. Even when it is determined in step S121 that only one phase difference AF area 1 is close, the driving direction of the focus lens is determined based on the defocus amount of the one phase difference AF area 1, and in that direction Hybrid AF is performed in which contrast AF is performed while driving the focus lens.

  On the other hand, if it is determined in step S120 that there is no phase difference AF area 1 close to the contrast AF area 3, the process proceeds to step S106 and only normal contrast AF is performed based on the contrast AF area 3. If it is determined in step S122 that the defocus directions of the plurality of phase difference AF areas 1 do not all match, the process proceeds to step S106 and only normal contrast AF is performed based on the contrast AF area 3.

  In the camera according to the fourth embodiment described above, even when the contrast AF area 3 and the phase difference AF area 1 do not overlap each other, the focus lens is based on the plurality of phase difference AF areas 1 close to the contrast AF area 3. Can be determined. As described above, if the contrast AF drive direction can be determined using the defocus amount of the phase difference AF area 1, AF can be performed quickly and with high accuracy. In the fourth embodiment, the example in which only the driving direction is determined based on the plurality of phase difference AF areas 1 has been described. However, the driving amount may be determined.

  In the first to fourth embodiments, the example in which the photographer manually sets the contrast AF area 3 to an arbitrary position by the contrast AF area selection unit 270 in step S102 has been described. However, the main subject may be automatically determined by image processing, and the contrast AF area 3 may be automatically set at that position. In this case, a human face may be detected by edge detection or the like, or a human face may be detected by skin color detection, and the detected area may be set as a range of the same subject as the main subject area. Further, the main subject may be detected by various other known methods.

  The arrangement position of the phase difference AF area 1 described above is not limited to the arrangement positions shown in FIGS. 2, 3, 6, 7, and 9. Further, the block division of the screen is not limited to the division form shown in FIGS. Furthermore, although the combination of the phase difference AF and the contrast AF has been described, the present invention is not limited to this combination, and the present invention can be applied to various hybrid AFs in which two different AF methods are combined. For example, a combination of contrast AF and external light passive AF, or a combination of contrast AF and active AF using infrared rays can be considered. Further, the embodiments of the phase difference AF and the contrast AF are not limited to those described above.

  In this embodiment, the lens barrel has been described as a replaceable camera. However, the present invention is not limited to this, and a lens-integrated camera may be used.

  In addition, the present invention is not limited to the above-described embodiment as long as the characteristics of the present invention are not impaired, and other forms conceivable within the scope of the technical idea of the present invention are also within the scope of the present invention. included.

It is a block diagram of the camera which incorporated the focus adjustment apparatus of this invention. It is a figure explaining a ranging area, and shows the case where a phase difference AF area and a contrast AF area overlap each other. It is a figure explaining a ranging area, and shows the case where a phase difference AF area and a contrast AF area do not overlap each other. It is a flowchart explaining operation | movement of 1st embodiment by this invention. It is a flowchart explaining operation | movement of 2nd embodiment by this invention. It is a figure explaining the ranging area when a screen is divided into blocks, where (a) shows the contrast AF area and the phase difference AF area close to each other, and (b) shows the contrast AF area and the phase difference AF area close to each other. Indicates the case of not doing. It is a figure which shows the positional relationship which the phase difference AF area and contrast AF area in 3rd Embodiment make. It is a figure which shows the flowchart of the process which the control circuit of 3rd Embodiment performs. It is a figure which shows distribution of the defocus of the phase difference AF area around the contrast AF area in the fourth embodiment. It is a figure which shows the flowchart of the process which the control circuit of 4th Embodiment performs.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Phase difference AF area 2 Range which can be detected with phase difference AF sensor 3 Contrast AF sensor 10 Camera body 20 Imaging element 100 Phase difference type AF detection element 110 Lens barrel 120 Shooting lens
120b Focus adjustment lens 130 AF drive motor 220 CCD control unit 230 Defocus amount calculation unit 240 Contrast detection unit 250 Lens target position calculation unit 260 Lens drive unit 270 Contrast AF area selection unit 300 Control circuit

Claims (10)

A phase difference type focus detection means for calculating focus detection information indicating a defocus amount and a defocus direction of a subject image in each of a plurality of first ranging areas spaced apart from each other in a shooting screen;
Area setting means for setting a second ranging area in the imaging screen;
Contrast-type focus detection means for calculating focus detection information representing a focus position in the second distance measurement area set in the shooting screen;
A focus adjustment control means for focusing control based on at least one of the focus detection information of the focus detection information of the focus detection information and the contrast type focus detection unit of the phase difference focus detection means,
And determining means for determining a range of a main subject that is identical to a main subject existing in the set second distance measuring area after the second distance measuring area is set by the area setting means. ,
The focus adjustment control unit, based on the focus detection information of the phase difference type focus detection unit and the contrast type focus detection unit, if the first distance measurement area exists in the range of the main subject determined by the determination unit. Focus adjustment control is performed, and if the first distance measurement area does not exist in the determined range of the main subject, focus adjustment control is performed based on focus detection information of the contrast type focus detection means. Focus adjustment device. The focus adjustment apparatus according to claim 1,
The focus adjustment apparatus characterized in that the determination means determines a face range of a subject person as the main subject. In the focus adjustment apparatus according to any one of claims 1 to 2,
The focus adjustment control means performs focus adjustment control based on the focus detection information of the phase difference type focus detection means if the first range finding area exists in the range of the main subject determined by the determination means. Thereafter, focus adjustment control is performed based on focus detection information of the contrast type focus detection means. In the focus adjustment apparatus according to any one of claims 1 to 3,
The phase difference type focus detection means calculates the focus detection information in a plurality of ranging areas,
A focus adjustment apparatus, further comprising first area setting means for setting at least one distance measurement area as the first distance measurement area. A focus adjustment method,
Calculating focus detection information representing a defocus amount and a defocus direction of a subject image in each of a plurality of first ranging areas spaced apart from each other in a shooting screen by phase difference focus detection;
Set the second ranging area at any position in the imaging screen,
Focus detection information representing a focus position of the photographing said second ranging areas set in the screen is calculated by the contrast type focus detection,
Focus adjustment control is performed based on focus detection information of at least one of the focus detection information of the phase difference type focus detection and the focus detection information of the contrast type focus detection,
After setting the second ranging area by the area setting means, determining a range of the main subject that maintains the sameness as the main subject existing in the set second ranging area;
If the first ranging area exists within the determined range of the main subject, focus adjustment control is performed based on focus detection information of the phase difference type focus detection and contrast type focus detection, and the determined main subject is determined. If the first distance measurement area does not exist in the range, focus adjustment control is performed based on focus detection information of the contrast type focus detection. The focus adjustment method according to claim 5, wherein
The focus adjustment method characterized in that the determination of a main subject that maintains the sameness as a main subject existing in the second distance measuring area is performed by determining a range of the face of the subject person as the main subject. In the focus adjustment method according to any one of claims 5 to 6,
The focus adjustment control performs the focus adjustment control based on the focus detection information of the phase difference type focus detection if the first distance measurement area exists in the determined range of the main subject, and then the contrast type control. A focus adjustment method comprising performing focus adjustment control based on focus detection information of focus detection. In the focus adjustment method according to any one of claims 5 to 7,
The phase difference type focus detection calculates the focus detection information in a plurality of ranging areas,
A focus adjustment method, wherein at least one ranging area is set as the first ranging area.   A camera comprising the focus adjustment device according to claim 1. A first focus detection unit that detects a focus adjustment state of a subject image by a phase difference AF method;
An area setting unit for setting a ranging area at an arbitrary position in the imaging screen;
A second focus detection unit for detecting a focus adjustment state by a contrast AF method in the set ranging area ;
A focus adjustment control unit capable of focus adjustment control of an optical system using at least one of the first focus detection unit and the second focus detection unit;
A determination unit that determines a main subject range that maintains the sameness as a main subject existing in the set ranging area after the distance setting area is set by the area setting unit ;
The focus adjustment control unit performs the focus adjustment control using the first focus detection unit and the second focus detection unit when the subject image of the first focus detection unit is included in the main subject range. And performing the focus adjustment control using the second focus detection unit when the subject image of the first focus detection unit is not included in the main subject range.

Images