JP2007286217A - Imaging apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an imaging apparatus made that is smaller in size and achieving high-speed and high-accuracy AF, as an imaging apparatus which performs climbing AF by driving an imaging device. <P>SOLUTION: A camera that is the imaging apparatus has a photographic lens whose focal position can be set, by displacing at least a part of an optical system; an imaging means which converts a subject image formed by the photographic lens into an electrical signal; and a moving mechanism which displaces the imaging means in the optical axis direction of the photographic lens. The focal position of the photographic lens is set to a predetermined position, when focusing operation is performed by controlling the moving mechanism. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an imaging apparatus that captures a subject image using an imaging element such as a digital camera or a video camera, and more particularly to an imaging apparatus that performs automatic focus adjustment using the imaging element.

  As shown in FIG. 7, the conventional single-lens reflex camera has a main mirror 3 and a sub mirror 4 in the camera body 1. When performing autofocus (hereinafter also simply referred to as “AF”), these mirrors allow Phase difference formed by a finder optical system 6 having a screen mat 9, a pentaprism 7, an eyepiece lens 8 and the like, a condenser lens 11, re-imaging lenses 12a and 12b, line sensors 13a and 13b, etc. The focus is adjusted by dividing it into the AF optical system 10, and at the time of shooting, these mirrors are retracted from the optical path to form a subject image on the film 2 or the image sensor 2. In the figure, reference numeral 5 denotes a mount surface for mounting the interchangeable lens on the camera body 1.

In the case of the above-described configuration, the finder optical system 6 and the AF optical system 10 are present, so that there is a disadvantage that the camera becomes large.
In the case of a digital single-lens reflex camera, as a method of eliminating this drawback and reducing the size of the camera, an imaging element such as a CCD for photographing is used, and the subject lens image is moved while moving the focus lens within the photographing lens at a predetermined interval. A liquid crystal monitor arranged on the back of the camera, etc., that detects high-frequency components as focus evaluation values and performs focus adjustment by so-called hill-climbing AF, which determines the focus lens position where the focus evaluation value is maximized, so-called hill-climbing AF There is a method in which the AF optical system 10 and the finder optical system 6 are eliminated by displaying the photographed image or the like.

  However, in the case of the above method, since the conventional interchangeable lens is not suitable for fine driving of the focus lens during the hill-climbing AF, it takes time for the focus adjustment, and the focus adjustment with high accuracy can be performed. There is no problem.

  Even if the lens drive mechanism is an interchangeable lens that is suitable for the hill-climbing AF described above, the apparatus becomes complicated due to an increase in the control signal line between the camera body and the interchangeable lens, or in the case of a large interchangeable lens. Since a large driving force is required, there arises a problem that power consumption increases.

As an example of a method for solving such a problem, as disclosed in Patent Document 1, the lens is not driven during focus adjustment, and the imaging unit including the imaging element is driven in the optical axis direction of the photographing lens to focus. An autofocus system that performs adjustment is known.
JP-A-7-177527

However, Patent Document 1 does not describe the position of the focus lens when the imaging unit is driven to perform focus adjustment.
Since the size of the flange back and back focus of the camera changes depending on the position of the focus lens, for example, as shown in FIG. 8, the focus lens in the interchangeable lens 22 is fixed at a position 25a in the vicinity of infinity. When focus adjustment is performed by driving the imaging unit in the main body 21, the position 24a of the normal image sensor (the position when the image sensor is fixed and focus detection is performed by driving the focus lens = the subject when the subject distance is infinite) Since it is necessary to drive the image sensor in the rear direction of the camera body (position 24b in the figure) rather than the position where the image is formed, there is a problem that the camera body is enlarged accordingly.

  The elements and symbols in FIG. 1 will be described. The camera body 21 includes an imaging unit that can move in the optical axis direction of the interchangeable lens 22, a mount surface 23 for mounting the interchangeable lens 22, and the like. The interchangeable lens 22 includes various photographing optical systems, a focus lens, and the like. The mount surface 23 has terminals for electrical communication between the camera body 21 and the interchangeable lens 22, and is used for mounting the interchangeable lens 22 on the camera body 21. The position 24a is a position of an image pickup device such as a CCD sensor when the image pickup unit is at an infinite end. The position 24b is a position of an image pickup device such as a CCD sensor when the image pickup unit is at the closest end. The position 25 a is an infinite end position of the focus lens in the interchangeable lens 22. Reference numeral 25 b denotes the closest end position of the focus lens in the interchangeable lens 22. Reference numeral 26 denotes a subject position close to photographing. Reference numeral 27a denotes an imaging position when the subject distance is infinite. Reference numeral 27 b denotes an image forming position when the subject distance is the shooting distance 26. Reference numeral 28 denotes an optical axis of the interchangeable lens 22.

  In view of the above circumstances, the present invention is an image pickup apparatus that performs hill-climbing AF by driving an image pickup device in order to reduce the size of an optical device such as a camera, increase the speed of AF, and increase the accuracy. An object of the present invention is to provide an imaging apparatus capable of performing accurate AF.

  In order to achieve the above object, an imaging apparatus according to a first aspect of the present invention includes a photographic lens capable of setting a focal position by displacing at least a part of an optical system, and a subject image formed by the photographic lens. An image pickup apparatus having an image pickup means for converting into an electrical signal and a moving mechanism for displacing the image pickup means in the optical axis direction of the taking lens, and performing the focus adjustment operation by controlling the move mechanism The focal position of the photographing lens is set to a predetermined position.

  The imaging apparatus according to a second aspect of the present invention is characterized in that, in the first aspect, in the focus adjustment operation, a hill-climbing focus adjustment operation is performed from the electrical signal converted by the imaging means. To do.

  In the imaging device according to a third aspect of the present invention, in the first aspect, the predetermined position is a focal position where an image formed by the photographing lens is focused on a subject at a close distance. Features.

The imaging device according to a fourth aspect of the present invention is characterized in that, in the first aspect, the predetermined position is set according to an operation mode.
The imaging device according to a fifth aspect of the present invention is characterized in that, in the first aspect, the predetermined position is set in accordance with a focal length of the photographing lens.

An image pickup apparatus according to a sixth aspect of the present invention is characterized in that, in the first aspect, the image pickup apparatus is an interchangeable lens camera.
The imaging device according to a seventh aspect of the present invention is the imaging device according to the first aspect, wherein the imaging unit displaced by the moving direction and the displacement direction of the optical system displaced to set the focal position of the photographing lens. The displacement direction is different.

  An imaging device according to an eighth aspect of the present invention is the imaging device according to the sixth aspect, wherein the imaging means is photographed without displacement when a photographing lens that can be driven in minute steps is mounted as the photographing lens. The focus adjustment operation is performed by the displacement of the lens.

  According to the present invention, in an imaging apparatus that performs hill-climbing AF by driving an imaging element in order to reduce the size of an optical device such as a camera, increase the speed of AF, and increase the accuracy, AF that is smaller, faster, and more accurate. It can be performed.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a schematic diagram for explaining a camera that is an imaging apparatus according to Embodiment 1 of the present invention.
As shown in the figure, the camera according to the present embodiment is configured by mounting an interchangeable lens 102 on a camera body 101.

  The camera body 101 has an imaging means (including an imaging element such as a CCD sensor) described later that can move in the optical axis direction of the interchangeable lens 102, a mount surface 103 for mounting the interchangeable lens, and the like. The mount surface 103 has a terminal for electrical communication between the camera body 101 and the interchangeable lens 102, and is a mount surface for mounting the interchangeable lens 102 on the camera body 101.

The interchangeable lens 102 includes various photographing optical systems, a focus lens, and the like.
In the same figure, the position of the image sensor, the position of the focus lens, the subject position, and the imaging position are also shown.

Reference numeral 104a denotes the position of the image pickup element when the image pickup means is at the closest end position.
Reference numeral 104b denotes the position of the image sensor when the imaging means is at the infinite end position.
Reference numeral 105 a denotes the closest end position of the focus lens in the interchangeable lens 102.

Reference numeral 105 b denotes an infinite end position of the focus lens in the interchangeable lens 102.
Reference numeral 106a denotes a subject position close to photographing.
Reference numeral 106b denotes a subject position at a finite distance within the photographing range.

Reference numeral 107a denotes an image forming position when the subject distance is the shooting distance 106a.
Reference numeral 107b denotes an imaging position when the subject distance is a finite distance 106b within the photographing range.

Reference numeral 107c denotes an imaging position when the subject distance is infinite.
Reference numeral 108 denotes an optical axis of the interchangeable lens 102.
FIG. 2 is a block diagram illustrating the configuration of the camera according to the present embodiment.

In the camera body 101, 111 is a CPU that performs communication with each operation control / calculation / interchangeable lens 102 of the camera.
Reference numeral 112 denotes an image sensor such as a CCD sensor, a position detector that detects the current position and transmits position information to the CPU 111, and the image pickup is driven and controlled in the optical axis direction of the interchangeable lens 102 by the image sensor driving unit 113. Means.

Reference numeral 113 denotes an image sensor driving unit that has an actuator such as a motor and controls the driving of the imaging unit 112 along the optical axis of the imaging lens by a control signal from the CPU 111.
Reference numeral 114 denotes an A / D conversion unit that converts an analog image signal output from the imaging unit 112 into a digital image signal.

  Reference numeral 115 denotes generation of image data by image processing such as white balance correction, distortion correction, and image compression based on the digital image signal output from the A / D conversion unit 114, and focus evaluation by detection of high-frequency components of the image signal. An image processing unit that calculates a value and displays image data on the display unit 116 according to an instruction from the CPU 111, stores the image data in the storage unit 117, re-images the stored image data, and the like. is there.

Reference numeral 116 denotes a display unit composed of a liquid crystal panel or the like for displaying a through image that has been subjected to image processing by the image processing unit 115 and image data stored in the storage unit 117.
Reference numeral 117 denotes storage means for storing the image data processed by the image processing means 115.

  In the interchangeable lens 102, 118 includes a focus lens and a position detection unit that detects the current position of the focus lens and transmits position information to the lens control unit 120, and forms a subject image on the imaging element of the imaging unit 112. This is a photographing lens unit.

Reference numeral 119 denotes lens driving means that has an actuator such as a motor and controls the driving of a focus lens for focus adjustment in the photographing lens unit 118.
Reference numeral 120 denotes lens control means for controlling the lens driving means 119 while monitoring position information of a focus lens for focus adjustment in accordance with an instruction from the CPU 111.

FIG. 3 is a flowchart for explaining an example of a shooting sequence of the camera according to the present embodiment.
As shown in the figure, when the power of the camera body 101 is turned on, first, in S101, it is determined whether or not the interchangeable lens 102 is attached to the camera body 101, and if it is attached (S101 is Y). ) Proceed to S102, and if not mounted (N in S101), wait for mounting.

  In S102, communication is performed between the camera body 101 and the interchangeable lens 102 through a communication terminal provided on the mount surface 103, and model information, optical characteristic data, various correction data, and the like of the interchangeable lens 102 are stored in the camera body 101. take in.

  In S103, the CPU 111 in the camera body 101 calculates the amount of extension data to the closest end of the focus lens in the photographing lens unit 118 of the interchangeable lens 102 based on the information captured in S102.

  In S104, the CPU 111 transmits the feed amount data and the feed command obtained in S103 to the lens control unit 120 in the interchangeable lens 102 through the communication terminal, and the lens control unit 120 drives the lens based on the sent feed amount data. The means 119 is controlled to move the focus lens in the photographic lens unit 118 to the closest end (see 105a in FIG. 1).

  In S105, the subject image formed on the image sensor in the image pickup unit 112 by the photographing lens unit 118 is photoelectrically converted by the image pickup device into an analog image signal, and the image processing unit 115 converts the analog image signal into A. Through image data is generated from the digital image signal obtained by A / D conversion by the / D conversion means 114 and displayed on the display means 116 (so-called live view display is started).

  In S106, it is determined whether or not the interchangeable lens 102 has been removed from the camera body 101. If it has not been removed (N in S106), the process proceeds to S107. If it has been removed (Y in S106), the process returns to S101 and waits for lens mounting. I do.

  In S107, it is determined whether or not the power of the camera body 101 is turned off. If the camera body 101 is on (S107 is N), the process proceeds to S108. If it is turned off (S107 is Y), the process proceeds to S112.

  In S108, it is determined whether or not the release switch is turned on. If the release switch is turned on (Y in S108), the process proceeds to S109. If the release switch remains in the off state (S108 is N), the process returns to S106.

  In S109, the CPU 111 controls the image sensor driving unit 113 to move the imaging unit 112 from the closest end position (closest in FIG. 4, refer to 104a in FIG. 1) to the infinite end position (FIG. 4) as shown in FIG. ∞, see 104b in FIG. 1) at predetermined intervals, the image processing means 115 detects the high frequency component of the image signal at each stop position, obtains a focus evaluation value, and evaluates the focus at each stop position. When it is determined that the value has exceeded the peak, the imaging device driving unit 113 moves the imaging unit 112 in the reverse direction to stop the focus evaluation value at a peak (mountain climbing AF).

  However, this hill-climbing AF is performed in a state where the focus lens in the photographic lens unit 118 is at the closest end position 105a. Therefore, before the hill-climbing AF is started, if the focus lens in the photographic lens unit 118 is not at the closest end position 105a, the lens control unit 120 controls the lens driving unit 119 under the control of the CPU 111, and the focus lens. Is moved to the closest end position 105a, and then this hill-climbing AF is performed.

  In S110, imaging is performed at the stop position of the imaging unit 112 detected by the hill-climbing AF in S109. Then, an analog image signal obtained by photoelectric conversion in the image pickup device in the image pickup unit 112 is converted into a digital image signal by the A / D conversion unit 114, and various filter processes, white balance correction, and image compression are performed by the image processing unit 115. Image data is generated by performing image processing such as the above.

In S111, the image data generated in S110 is stored in the storage unit 117, and the process returns to S106 and again shifts to the photographing standby state.
In S112, predetermined end processing such as saving various data and disconnecting the power supply system is executed, and this flow ends.

  Thus, in the shooting sequence of this flow, before starting the AF operation, the focus lens in the shooting lens unit 118 is moved to the closest end position 105a, and the imaging unit 112 in the camera body 101 is moved closer to the camera. As shown in FIG. 4, the focus evaluation value at each stop position of the image pickup means 112 is changed to the high frequency of the subject image signal while moving at a predetermined interval in the optical axis direction of the interchangeable lens 102 from the end position (see 104a in FIG. 1). Mountain climbing AF is performed in which the imaging means 112 is moved to a position where the focus evaluation value is finally maximized.

  As described above, according to the first embodiment, when performing the hill-climbing AF by moving the imaging unit 112, the focus lens in the photographic lens unit 118 is fixed at the closest end position 105a. The change range of the imaging position is the area where the main mirror for guiding the subject light beam to the finder optical system in the conventional single-lens reflex camera is present, and this area is set as the movement range of the imaging means 112 during hill-climbing AF. Thus, since it is possible to eliminate the viewfinder optical system and AF optical system without requiring a space for movement on the rear surface of the camera, AF with high speed and high accuracy can be achieved with a smaller camera than before. It can be performed.

In the first embodiment, the following modifications are possible.
(Modification 1-1)
The fixed position of the focus lens in the photographic lens unit 118 when performing the hill-climbing AF by moving the imaging unit 112 does not necessarily need to be the exact position at the closest end, and is acquired at the time of communication with the interchangeable lens 102. Depending on the optical characteristics of the interchangeable lens 102, the camera mode (operation mode), or in the case of a zoom lens, depending on the current focal length, etc. It may be a specified predetermined position and the closest end position at each focal length.

  For example, when changing the fixed position of the focus lens according to the shooting mode, the macro lens is set to a position for shooting at a conventional subject distance of 10 cm, and to the position for shooting 60 cm in the normal mode. When the fixed position of the focus lens is changed in accordance with the focal length, the position for 60 cm photographing on the wide angle side and the position for photographing 1 m on the telephoto side may be used.

By doing as described above, the moving range of the image pickup means 112 can be limited to a narrow range as compared with the case where the focus lens is simply fixed at the closest end position, so that further reduction in power consumption and increase in AF speed are achieved. be able to.
(Modification 1-2)
Although FIG. 4 shows an example in which the imaging unit 112 is moved from the closest side, the movement start position may be the infinite side, the previous stop position, a position corresponding to each camera mode, or the like. .
(Modification 1-3)
When obtaining the focus evaluation value, it is not always necessary to stop the imaging unit 112. For example, the focus evaluation value may be obtained in synchronization with the vertical synchronization signal of the image sensor while moving at a predetermined speed. By doing so, it is possible to further speed up AF.
(Modification 1-4)
Depending on the value of the focus evaluation value and its tendency, the moving speed and interval of the imaging means 112 are changed, and the position at which the focus evaluation value peaks is predicted from several focus evaluation values. You may devise precision and speedup.
(Modification 1-5)
In the above description, the interchangeable lens camera has been described. However, the present embodiment may be applied to a camera integrated with a photographing lens.

  FIG. 5 is a schematic diagram for explaining a camera that is an image pickup apparatus according to Embodiment 2 of the present invention. In the figure, the same elements as those shown in FIG. 1 are denoted by the same reference numerals.

  In FIG. 5, reference numeral 201 denotes a camera body having an imaging means 112 that can move in the optical axis direction of the interchangeable lens 102, a mount 103 for mounting the interchangeable lens, a mirror 202 for bending the interchangeable lens optical axis, and the like.

The mirror 202 is a mirror for bending the interchangeable lens optical axis 108 in a direction different from the incident direction (downward direction of the camera body 201) in the camera body 201.
As described above, in the camera according to the present embodiment, the mirror 202 for changing the direction of the optical axis 108 of the interchangeable lens in the downward direction is arranged in the camera body 201, and the moving direction of the imaging unit 112 is the vertical direction. It is comprised as follows.

Other configurations and operations are the same as those in the first embodiment.
As described above, according to the present embodiment, since the space on the back surface of the camera can be reduced by bending the subject light beam in the camera, a camera thinner than the conventional one capable of high-speed and high-precision AF is provided. Can do.

In the second embodiment, the following modifications are possible.
(Modification 2-1)
The changing direction of the interchangeable lens optical axis 108 is not limited to the downward direction, and may be the upward direction or the lateral direction of the camera body 201. By doing so, a design with a higher degree of freedom becomes possible.
(Modification 2-2)
The means for changing the direction of the optical axis 108 of the interchangeable lens within the camera body 201 is not limited to the mirror 202 but may be other optical means such as a prism.
(Modification 2-3)
The luminous flux of the subject may be bent at an angle other than a right angle as shown in FIG. The displacement direction of the focus lens (part or all) and the displacement direction of the image sensor may be set as appropriate so as to be suitable for mounting on the camera.
(Modification 2-4)
Similar to the first embodiment, this embodiment may be applied not only to a lens-interchangeable camera but also to a camera integrated with a photographing lens.

  The camera that is the imaging apparatus according to the third embodiment of the present invention has the same basic configuration and normal operation as those of the first embodiment, but is suitable for performing hill-climbing AF such as a stepping motor and an ultrasonic motor. When the interchangeable lens 102 provided in the lens driving means 119 with an actuator capable of driving the focus lens in minute steps is attached to the camera body 101, the focus lens of the attached interchangeable lens 102 is connected to the imaging means 112. When the object is at the near end, the subject image at the closest distance to the image is fixed at the closest end position 104a of the image pickup element formed on the image pickup element, and the focus lens of the interchangeable lens 102 is driven to perform hill-climbing AF. It is what. In the interchangeable lens single-lens reflex camera, phase difference AF is used. In this method, the lens is driven according to the detected defocus amount. This drive amount is larger than the drive amount required for hill-climbing AF. In general, these interchangeable lenses may not be suitable for operations that repeat minute driving required for hill-climbing AF.

FIG. 6 is a flowchart for explaining an example of a shooting sequence of the camera according to the present embodiment.
As shown in the figure, when the power of the camera body 101 is turned on, first, in S301, it is determined whether or not the interchangeable lens 102 is attached to the camera body 101, and if it is attached (S301 is Y). ) Proceed to S302, and if not mounted (N in S301), wait for mounting.

  In S <b> 302, communication is performed between the camera body 101 and the interchangeable lens 102 through a communication terminal provided on the mount surface 103, and model information, optical characteristic data, various correction data, and the like of the interchangeable lens 102 are stored in the camera body 101. take in.

  In S303, it is determined whether or not the mounted interchangeable lens 102 is a hill-climbing AF lens (a lens suitable for performing the hill-climbing AF described above), and if it is a hill-climbing AF lens (Y in S303), S306. If not a hill-climbing AF lens (N in S303), the process proceeds to S304.

  In S304, based on the information captured in S302, the CPU 111 in the camera body 101 calculates the feed amount data to the closest end of the focus lens in the photographing lens unit 118 of the interchangeable lens 102.

  In S305, the CPU 111 transmits the feed amount data and the feed command obtained in S304 to the lens control unit 120 in the interchangeable lens 102 through the communication terminal, and the lens control unit 120 drives the lens based on the sent feed amount data. The means 119 is controlled to drive the focus lens in the photographic lens unit 118 to the closest end (see 105a in FIG. 1).

  In step S306, the subject image formed on the image sensor in the image pickup unit 112 by the photographing lens unit 118 is photoelectrically converted by the image pickup device into an analog image signal, and the image processing unit 115 converts the analog image signal to A. Through image data is generated from the digital image signal obtained by A / D conversion by the / D conversion means 114 and displayed on the display means 116.

  In S307, it is determined whether or not the interchangeable lens 102 has been removed from the camera body 101. If it has not been removed (N in S307), the process proceeds to S308, and if it has been removed (Y in S307), the process returns to S301 and waits for lens mounting. I do.

  In S308, it is determined whether or not the power of the camera body 101 is turned off. If the camera is turned on (N in S308), the process proceeds to S309. If it is turned off (Y in S308), the process proceeds to S315.

  In S309, it is determined whether or not the release switch is turned on. If it is turned on (Y in S309), the process proceeds to S310, and if it is in the off state (S309 is N), the process returns to S307.

  In S310, it is determined whether or not the mounted interchangeable lens 102 is a hill-climbing AF lens. If it is a hill-climbing AF lens (S310 is Y), the process proceeds to S312. N) Go to S311.

  In step S311, the CPU 111 controls the image sensor driving unit 113 to move the imaging unit 112 from the closest end position (closest in FIG. 4, refer to 104a in FIG. 1) to the infinite end position (see FIG. 4). ∞, see 104b in FIG. 1) at predetermined intervals, the image processing means 115 detects the high frequency component of the image signal at each stop position, obtains a focus evaluation value, and evaluates the focus at each stop position. When it is determined that the value has exceeded the peak, the imaging device driving unit 113 moves the imaging unit 112 in the reverse direction to stop the focus evaluation value at a peak (mountain climbing AF by driving the imaging unit).

  However, the hill-climbing AF by driving the imaging unit is performed in a state where the focus lens in the photographing lens unit 118 is at the closest end position 105a. Therefore, before the hill-climbing AF starts, if the focus lens in the photographic lens unit 118 is not at the closest end position 105a, the lens control unit 120 controls the lens driving unit 119 under the control of the CPU 111, and the focus lens. Is moved to the closest end position 105a, and then the mountain climbing AF is performed.

  In S312, the lens control unit 120 that has received the hill-climbing AF execution command from the CPU 111 controls the lens driving unit 119 to move the focus lens in the photographing lens unit 118 to the closest end position (see FIG. 4). 4 at a predetermined interval from a position close to 4 (see 105a in FIG. 1) to an infinite end position (∞ in FIG. 4 and 105b in FIG. 1), and the image processing means 115 converts the high-frequency component of the image signal at each stop position. The focus evaluation value is detected and detected, and the obtained focus evaluation value is transmitted from the CPU 111 to the lens control unit 120 as needed. When the lens control unit 120 determines that the focus evaluation value at each stop position exceeds the peak, the lens driving unit 119 moves the focus lens in the reverse direction to stop the focus evaluation value at the peak ( Mountain climbing AF with focus lens drive).

  However, in this hill-climbing AF by moving the focus lens, when the imaging unit 112 has the focus lens of the attached interchangeable lens 102 at the closest end position 105a, the subject image at the closest distance to the image is formed on the image sensor. This is performed in a state where the image sensor is at the closest end position 104a. Therefore, before the hill-climbing AF is started, if the image pickup unit 112 is not at the closest end position 104a of the image pickup device, the CPU 111 controls the image pickup device driving unit 113 so that the image pickup unit 112 is moved to the close end position 104a of the image pickup device. The hill-climbing AF is performed. Further, the movement of the focus lens is not limited from the close end to the infinite end, but may be moved from the infinite end to the close end or in a predetermined direction from the previous stop position.

  In S313, imaging is performed at the stop position of the imaging unit 112 detected by the hill-climbing AF by driving the imaging unit in S311 or the stop position of the focus lens detected by the hill-climbing AF by driving the focus lens in S312. Then, an analog image signal obtained by photoelectric conversion in the image pickup device in the image pickup unit 112 is converted into a digital image signal by the A / D conversion unit 114, and various filter processes, white balance correction, and image compression are performed by the image processing unit 115. Image data is generated by performing image processing such as the above.

In S314, the image data generated in S313 is stored in the storage unit 117, and the process returns to S307 and again shifts to the imaging standby state.
In step S315, predetermined processing such as saving various data and disconnecting the power supply system is executed, and this flow ends.

  As described above, in the imaging sequence of the present flow, the interchangeable lens 102 provided with the lens driving unit 119 includes an actuator that can drive the focus lens in minute steps, which is suitable for performing hill-climbing AF such as a stepping motor and an ultrasonic motor. Is mounted on the camera body 101, the imaging means 112 is used to form a subject image at the shortest shooting distance on the image sensor when the focus lens of the mounted interchangeable lens 102 is at the closest end position 105a. The image sensor is fixed at the closest end position 104a and the focus lens of the interchangeable lens 102 is driven to perform hill-climbing AF.

  As described above, according to the third embodiment, depending on whether or not the interchangeable lens 102 is suitable for hill-climbing AF, it is switched between the imaging unit 112 and the focus lens in the photographing lens unit 118. The optimum hill-climbing AF can be executed according to the combination of the interchangeable lens 102 and the camera body 101, and AF with higher speed and higher accuracy can be performed with a smaller camera than the conventional one.

In the third embodiment, the following modifications are possible.
(Modification 3-1)
In the description of FIG. 6, lens control during hill-climbing AF is performed by the lens control unit 120. However, the CPU 111 may execute lens control through the lens control unit 120.

  Although the present invention has been described in detail above, the present invention is not limited to the above-described embodiment, and it is needless to say that various improvements and changes may be made without departing from the gist of the present invention.

1 is a schematic diagram for explaining a camera that is an imaging apparatus according to Embodiment 1. FIG. 1 is a block diagram illustrating a configuration of a camera according to Embodiment 1. FIG. 6 is a flowchart for explaining an example of a shooting sequence of the camera according to the first embodiment. It is a figure which shows an example of the relationship between the imaging means position or focus lens position at the time of mountain climbing AF, and a focus evaluation value. FIG. 6 is a schematic diagram for explaining a camera that is an imaging apparatus according to a second embodiment. 12 is a flowchart for explaining an example of a shooting sequence of a camera according to a third embodiment. It is a figure which shows the structure of the conventional single-lens reflex camera. It is a schematic diagram for demonstrating the conventional single-lens reflex camera.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Camera body 2 Film or image pick-up element 3 Main mirror 4 Sub mirror 5 Mount surface 6 Viewfinder optical system 7 Penta prism 8 Eyepiece 9 Screen mat 10 Phase difference AF optical system 11 Condenser lens 12a, 12b Re-imaging lens 13a, 13b Line sensor 14 Light beam 21 Camera body 22 Interchangeable lens 23 Mount surface 24a, 24b Image sensor position 25a, 25b Focus lens position 26 Subject position 101 Camera body 102 Interchangeable lens 103 Mount surface 104a, 104b Image sensor position 105a, 105b Focus lens position Position 106a, 106b Subject position 107a, 107b, 107c Image forming position 108 Optical axis 111 CPU
DESCRIPTION OF SYMBOLS 112 Image pickup means 113 Image pick-up element drive means 114 A / D conversion means 115 Image processing means 116 Display means 117 Storage means 118 Shooting lens part 119 Lens drive means 120 Lens control means 201 Camera body 202 Mirror

Claims (8)

A photographic lens capable of setting a focal position by displacing at least a part of the optical system;
Imaging means for converting a subject image formed by the photographing lens into an electrical signal;
A moving mechanism for displacing the imaging means in the optical axis direction of the photographing lens;
An imaging device having
When performing the focus adjustment operation by controlling the moving mechanism, the focal position of the photographing lens is set to a predetermined position;
An imaging apparatus characterized by that. In the focus adjustment operation, a hill-climbing focus adjustment operation is performed from the electrical signal converted by the imaging means.
The imaging apparatus according to claim 1. The predetermined position is a focal position where an image formed by the photographing lens is focused on a subject at a close distance,
The imaging apparatus according to claim 1. The predetermined position is set according to the operation mode.
The imaging apparatus according to claim 1. The predetermined position is set according to a focal length of the photographing lens.
The imaging apparatus according to claim 1. The imaging device is an interchangeable lens camera.
The imaging apparatus according to claim 1. The displacement direction of the optical system displaced to set the focal position of the photographing lens is different from the displacement direction of the imaging means displaced by the moving mechanism;
The imaging apparatus according to claim 1. When a photographic lens that can be driven in minute steps is attached as the photographic lens, a focus adjustment operation is performed by displacing the photographic lens without displacing the imaging means.
The imaging apparatus according to claim 6.

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