JP2007017530A - Imaging apparatus and control method for imaging apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To easily grasp the projected position of auxiliary light. <P>SOLUTION: The imaging apparatus is is constituted so that the live view display of a subject image is performed and the projected position of auxiliary light is displayed on a TFT liquid crystal 104. Therefore, when light is not projected to an appropriate position due to mounting backlash caused during the connection of an external flash device 105 to the main body 102 of a camera, a photographer can adjust the projected position while viewing the display. Thus, as long as wasteful energy to project light to a range that is made wider to a certain degree taking account of mounting backlash is projected in an appropriate range so as to have the same quantity of light projection energy, light can be projected farther. In addition, as long as the distance of light projection is not extended, a quantity of light projection energy can be reduced and, therefore, power consumed for light projection can be suppressed. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an imaging apparatus, an imaging apparatus control method, and a computer program. For example, the present invention relates to a technique suitable for use in correcting a projection position of auxiliary light that assists a focus detection function.

  Conventionally, in a camera system that can be used by connecting an external flash device having a function of projecting auxiliary light, when performing focus detection of a subject during shooting, for example, the contrast of the subject is obtained under low brightness. If it is determined that the detection is impossible, the auxiliary flashlight is controlled to the external flash device to assist the focus detection function (for example, pattern projection using infrared light or simply for increasing the brightness). Focus detection is performed while performing lamps.

  As an example of a conventional camera, the infrared light projecting unit of the camera is irradiated toward the subject, and the infrared light reflected by the subject is received by the infrared light receiving unit. 2. Description of the Related Art A camera equipped with an active ranging type light projection system that measures distance is known. The camera described in Patent Document 1 corrects an error in the light condensing position of the light projecting system. When the irradiation direction of the light projecting system is changed, an error occurs in the light condensing position of infrared light. Therefore, the light collecting position is adjusted by eliminating the error of the light collecting position of the light projecting system by adjusting the vertex angle of the variable vertex angle prism.

JP-A-06-82684

  In the conventional camera system, since an external flash device is connected to the camera body, a certain amount of attachment is required for the connection. Therefore, there has been a problem that a shift occurs in the position where the auxiliary light is projected.

  In addition, when the external flash device attached to the L-shaped grip or tripod indirectly is controlled by a communication means such as a wired connection while being away from the camera body instead of the assumed mounting position of the camera body, Since the photographer does not know where the light projection position is, there is a problem that much trouble is required when using the auxiliary light.

  Further, a normal camera generally projects a wide range of light in consideration of the attachment caused by the connection of an external flash device to the camera body. However, when light is projected over a wide range, there is a problem in that the amount of light is dispersed and the reach distance of the light is shortened. In addition, there is a problem that the larger the light is projected in consideration of the mounting, the more energy is required and the power consumption required for the light projection is increased.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to improve the accuracy of the projection position of auxiliary light.

  The image pickup apparatus of the present invention is an object image formed by a photographic lens that is detachably or indirectly connectable to a light projecting unit that projects auxiliary light for detecting a focus adjustment state of the photographic lens by a focus detection unit. An image pickup apparatus having an image pickup device that performs photoelectric exchange, a light projection control unit that controls to project auxiliary light, and a calibration mode that performs an operation for correcting the light projection position of the auxiliary light. Auxiliary light calibration mode setting means for setting, and in the calibration mode set by the auxiliary light calibration mode setting means, displays the subject image formed on the image sensor and emits the auxiliary light Display means for displaying the light projection position.

  The control method of the image pickup apparatus of the present invention is formed by a photographic lens that is attachable / detachable or indirectly connectable to a light projecting unit that projects auxiliary light for detecting a focus adjustment state of the photographic lens by the focus detection unit. A method for controlling an image pickup apparatus having an image pickup device for photoelectrically exchanging a subject image, comprising: a light projection control step for controlling to project auxiliary light; and an operation for correcting the light projection position of the auxiliary light. In the auxiliary light calibration mode setting step for setting the calibration mode to be performed, and in the calibration mode set in the auxiliary light calibration mode setting step, the subject image formed on the image sensor is displayed, And a display step for displaying a projection position of the auxiliary light to be projected.

  The computer program of the present invention is an object image formed by a photographic lens that can be detachably or indirectly connected to a light projecting unit that projects auxiliary light for detecting a focus adjustment state of the photographic lens by a focus detection unit. A program for causing a computer to execute a control method of an image pickup apparatus having an image pickup device that performs photoelectric exchange, and for correcting a light projection position of the auxiliary light, and a light projection control step for controlling the light to project auxiliary light In the auxiliary light calibration mode setting step for setting the calibration mode for performing the operation, and the calibration mode set in the auxiliary light calibration mode setting step, display of the subject image formed on the image sensor is performed. And a display step for displaying a projection position of the auxiliary light to be projected Characterized in that to execute the law to a computer.

  According to the present invention, if it has the same amount of light projecting energy, it is possible to project light farther. In addition, if the reach distance of the light projection is not increased, the amount of light projection energy of the camera can be reduced, so that power consumption required for the light projection can be suppressed.

(First embodiment)
FIG. 1 shows a configuration of a digital single-lens reflex camera system according to an embodiment of the present invention. The camera system according to the present embodiment includes a photographing lens 101 and a digital single-lens reflex camera (imaging device: hereinafter referred to as a camera body) 102 in which the photographing lens 101 can be attached and detached.
In FIG. 1, the photographing lens 101 is composed of a plurality of lens groups. By communicating with the taking lens 101, the camera body 102 can move all or part of it to change the focal length or adjust the focus.

  The camera main body 102 also has a function setting dial 103 for setting camera functions, and can select shutter priority shooting, aperture priority shooting, and the like. The digital single-lens reflex camera system of this embodiment is characterized in that the function setting dial 103 has an auxiliary light calibration mode. In addition, the camera body 102 includes a TFT liquid crystal 104 as an image display device that displays a captured subject image or a subject image formed on the imaging element in a live view display.

  In addition, an external flash device 105 having a function of projecting auxiliary light for assisting the focus detection means is connected to an accessory shoe (not shown) at the top of the camera. Through this accessory shoe, the camera body 102 can perform flash control and auxiliary light control of the external flash device 105. 106 is an operation button for adjusting the projection angle of the auxiliary light, and is used for adjusting the position within an appropriate AF auxiliary light control range.

FIG. 2 is a diagram showing the external flash device 105 used in the present embodiment.
The external flash device 105 has a function of emitting the strobe light 21 and projecting the AF auxiliary light 22 as shown in FIG. In the present embodiment, only the operation when the function setting dial 103 of FIG. 1 is set to the auxiliary light calibration mode will be described, and other imaging operations and the like will be omitted.

  When the function setting dial 103 of FIG. 1 is set to the auxiliary light calibration mode, the camera body 102 performs auxiliary light projection control on the external flash device 105 and also performs live view display on the TFT liquid crystal 104.

  3A to 3E are views showing an example of live view display in the TFT liquid crystal 104. FIG. If the auxiliary light is infrared auxiliary light, the live view display can display with many extracted infrared components and can be adjusted more easily.

  FIG. 3A shows an example of the live view display of the TFT liquid crystal 301, and the cross at the center indicates the AF sensor position 302 used when the camera body 102 performs distance measurement of the center of the screen ( It is not always necessary to display on the TFT liquid crystal 301). The camera body 102 performs a focus detection operation based on information obtained from an AF sensor (not shown) during distance measurement. As a means for detecting the focal point, a phase difference detection method using a light beam incident from the photographing lens 101 is used. Further, the AF auxiliary light needs to be projected so as to cover the entire sensor.

  Reference numeral 303 in FIG. 3B denotes a conventional AF auxiliary light control range. As the AF auxiliary light control range 303, since a considerably wide range is projected in consideration of the mounting of the external flash device 105, as shown in FIG. It can be seen that even if the center of the light control range 304 is shifted, it is absorbed by the wide light projection range.

  In this embodiment, a narrow AF auxiliary light control range as indicated by reference numeral 305 in FIG. 3D is set. In this way, by setting the narrow AF auxiliary light control range 305, the range is narrower, but the reach distance can be further increased compared to the conventional AF auxiliary light control range 303 in FIG. 3B. Features are obtained.

  However, when the narrow AF auxiliary light control range 305 is set, there may be a problem that the AF auxiliary light control range 305 is deviated from the AF sensor position 302 due to the attachment of the external flash device 105. In this case, the AF sensor cannot measure the distance. In the present embodiment, in order to eliminate such a problem, an appropriate AF auxiliary light control range 306 is displayed. As a result, as shown in FIG. 3E, the photographer can adjust the position of the removed AF auxiliary light control range 305 to be an appropriate AF auxiliary light control range 307.

FIG. 5 is a diagram illustrating a configuration example of the camera body 102 according to the present embodiment.
In FIG. 5, reference numeral 501 denotes an imaging unit including a lens, a shutter, a diaphragm, a CCD, and the like. Reference numeral 502 denotes an A / D converter that converts an analog video signal imaged by the imaging unit 501 into digital image data. A signal processing circuit 503 performs processing such as gamma correction and WB on the image data output from the A / D converter 502, and outputs it to the bus 504, where the image data is stored in the memory 506.

  A compression circuit 505 compresses and encodes an image signal according to a well-known JPEG format. Reference numeral 506 denotes a memory which stores the image signal input from the signal processing circuit 503 and outputs it to the circuits of the respective devices via the buses 504 and 508. Also, the image signal from each circuit is stored.

  Reference numeral 507 denotes a display unit including the TFT liquid crystal 104 and its driving unit, and displays an image input from the memory 506, an image stored in the storage device 511, or a menu screen.

  Reference numeral 509 denotes an operation unit that performs operation and control of the operation of the camera body 102, and has various switches such as a menu button and a playback button. The auxiliary light calibration mode is set through this operation unit. An MPU (Micro Processing Unit) 510 controls each circuit of the apparatus according to software stored in a memory (not shown). In the present embodiment, auxiliary light control is performed on the external flash device 105 via an interface (I / F) 512 described later.

  A storage device 511 is a flash memory card or the like that can be attached to and detached from the camera body 102, stores an image signal input via the bus 508, reads out the stored image signal, and outputs each circuit via the bus 508. Output to. Reference numeral 512 denotes an external communication interface (I / F) that transfers signals to and from the external flash device 105.

  Here, the operation of the camera system that performs the auxiliary light calibration will be described with reference to the flowchart shown in FIG. In the present embodiment, when the function setting dial 103 is set to the auxiliary light calibration mode, the camera body 102 enters the auxiliary light calibration mode and executes the following flow.

  When the process is started, first, in step S401, it is checked whether the auxiliary light calibration mode has been entered or not. If the result of this confirmation is the auxiliary light calibration mode, the process proceeds to step S402. If the result of confirmation in step S401 is that the mode is OFF, the process jumps to step S407.

  In the camera body 102, an external flash device 105 having a function of projecting AF auxiliary light 22 for assisting the focus detection means is connected to an accessory shoe (not shown) at the top of the camera. In step S <b> 402, the camera body 102 performs auxiliary light control on the external flash device 105 through this accessory shoe, and projects AF auxiliary light 22. Next, in step S403, the captured subject image of the camera body 102 or the subject image formed on the image sensor is displayed on the TFT liquid crystal 104, which is an image display device, in a live view.

  In step S404, an appropriate auxiliary light control range is displayed on the TFT liquid crystal 104. Thereafter, the process proceeds to step S405, and it is checked whether the auxiliary light calibration mode is maintained or not. If the result of this confirmation is the auxiliary light calibration mode, the process returns to step S402. As a result, the user can adjust the attachment of the external flash device 105 and match the projection range with the appropriate projection position. If they can be matched, the user exits the auxiliary light calibration mode. Therefore, as a result of the confirmation in step S405, it is determined that the auxiliary light calibration mode is not maintained. Accordingly, the process proceeds to step S406. Further, when matching, it can be adjusted more easily by guiding with matching display or the like.

  In step S406, in response to the exit from the auxiliary light calibration mode in step S405, the auxiliary light projection control is prohibited and the process proceeds to step S407. In step S407, in response to the exit from the auxiliary light calibration mode in step S405, the live view display of the TFT liquid crystal 104 is turned off and the process ends.

(Second Embodiment)
In the above-described embodiment, the case where the projection range deviates from an appropriate projection position due to the attachment of the external flash device 105 has been described. In the imaging apparatus of the present invention, the external flash device 105 is indirectly attached to an L-shaped grip, a tripod, etc. with the external flash device 105 away from the camera body 102, and the projection position of the auxiliary light is set by a communication means such as a wire. It is also possible to adjust.

Also in this case, when changing the projection angle of the AF auxiliary light 22 of the external flash device 105, the user can operate the operation button 106 while watching the live view display of the TFT liquid crystal 301. It is easy to match the appropriate light projection position.
In the above description, the display on the TFT liquid crystal 301 is used. However, the display content is not limited to this, and the display content on the TFT liquid crystal 301 may be displayed on the monitor.

(Another embodiment according to the present invention)
Each unit constituting the imaging apparatus and each step of the imaging apparatus control method in the embodiment of the present invention described above can be realized by operating a program stored in a RAM or ROM of a computer. This program and a computer-readable recording medium recording the program are included in the present invention.

  Further, the present invention can be implemented as, for example, a system, apparatus, method, program, or recording medium, and can be applied to a system composed of a plurality of devices. Moreover, you may apply to the apparatus which consists of one apparatus.

  In the present invention, a software program (in the embodiment, a program corresponding to the flowcharts shown in FIGS. 4 and 6) that realizes the functions of the above-described embodiments is directly or remotely supplied to a system or apparatus, This includes the case where the system or apparatus computer also achieves by reading and executing the supplied program code.

  Accordingly, since the functions of the present invention are implemented by computer, the program code installed in the computer also implements the present invention. In other words, the present invention includes a computer program itself for realizing the functional processing of the present invention.

  In that case, as long as it has the function of a program, it may be in the form of object code, a program executed by an interpreter, script data supplied to the OS, and the like.

  As a recording medium for supplying the program, for example, floppy (registered trademark) disk, hard disk, optical disk, magneto-optical disk, MO, CD-ROM, CD-R, CD-RW, magnetic tape, nonvolatile memory card ROM, DVD (DVD-ROM, DVD-R) and the like.

  As another program supply method, a client computer browser is used to connect to an Internet homepage, and the computer program itself of the present invention or a compressed file including an automatic installation function is downloaded from the homepage to a recording medium such as a hard disk. Can also be supplied.

  It can also be realized by dividing the program code constituting the program of the present invention into a plurality of files and downloading each file from a different homepage. That is, a WWW server that allows a plurality of users to download a program file for realizing the functional processing of the present invention on a computer is also included in the present invention.

  In addition, the program of the present invention is encrypted, stored on a recording medium such as a CD-ROM, distributed to users, and key information for decryption is downloaded from a homepage via the Internet to users who have cleared predetermined conditions. It is also possible to execute the encrypted program by using the key information and install the program on a computer.

  In addition to the functions of the above-described embodiments being realized by the computer executing the read program, the OS running on the computer based on the instructions of the program is used for the actual processing. The functions of the above-described embodiment can be realized by performing some or all of the processes.

  Furthermore, after the program read from the recording medium is written in a memory provided in a function expansion board inserted into the computer or a function expansion unit connected to the computer, the function expansion board or The CPU or the like provided in the function expansion unit performs part or all of the actual processing, and the functions of the above-described embodiments are realized by the processing.

It is a figure which shows the example of an external structure of the digital single-lens reflex camera system used in the 1st Embodiment of this invention. It is a figure which shows an example of the external flash apparatus used in the 1st Embodiment of this invention. It is a figure which shows an example of the live view display in the 1st Embodiment of this invention. It is a flowchart which shows the operation | movement procedure of the camera system which performs auxiliary light calibration in the 1st and 2nd embodiment of this invention. It is a figure which shows the internal structural example of the camera in the 1st Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 101 Shooting lens 102 Camera body 103 Function setting dial 104 TFT liquid crystal 105 External flash device 106 Operation button 301 TFT liquid crystal 302 AF sensor position 303 Conventional AF auxiliary light control range 304 Conventional AF auxiliary light control range (rare generation)
305 AF auxiliary light control range in the first embodiment (generation of rattling)
306 Suitable AF auxiliary light control range in the first embodiment 307 AF auxiliary light control range in the first embodiment (after correction)

Claims (5)

An image sensor that is detachably or indirectly connectable to a light projecting unit that projects auxiliary light for detecting a focus adjustment state of the photographing lens by a focus detection unit, and that photoelectrically exchanges an object image formed by the photographing lens. An imaging device comprising:
Projection control means for controlling to emit auxiliary light;
An auxiliary light calibration mode setting means for setting a calibration mode for performing an operation for correcting the projection position of the auxiliary light;
In the calibration mode set by the auxiliary light calibration mode setting means, it has a display means for displaying a subject image formed on the image sensor and displaying a projection position of the auxiliary light to be projected. An imaging apparatus characterized by the above. The light projecting means can change the light projection angle of the auxiliary light,
The imaging apparatus according to claim 1, wherein the projection control unit controls the projection angle of the auxiliary light to be changed in a state where the projection unit is connected. An operation member capable of operating a light projection angle of the light projecting means;
The light projection control unit controls a light projection angle of auxiliary light projected from the light projection unit according to an operation state of the operation member in a state where the light projection unit is connected. The imaging device according to claim 2. An image sensor that is detachably or indirectly connectable to a light projecting unit that projects auxiliary light for detecting a focus adjustment state of the photographing lens by a focus detection unit, and that photoelectrically exchanges an object image formed by the photographing lens. A method for controlling an imaging apparatus having:
A light projecting control step for controlling to emit auxiliary light;
An auxiliary light calibration mode setting step for setting a calibration mode for performing an operation for correcting the projection position of the auxiliary light; and
In the calibration mode set in the auxiliary light calibration mode setting step, the display includes displaying a subject image formed on the image sensor and displaying a projection position of the auxiliary light to be projected. A control method characterized by the above. An image sensor that is detachably or indirectly connectable to a light projecting unit that projects auxiliary light for detecting a focus adjustment state of the photographing lens by a focus detection unit, and that photoelectrically exchanges an object image formed by the photographing lens. A program for causing a computer to execute a control method of an imaging apparatus having
A light projecting control step for controlling to emit auxiliary light;
An auxiliary light calibration mode setting step for setting a calibration mode for performing an operation for correcting the projection position of the auxiliary light; and
A control step of displaying a subject image formed on the image sensor and displaying a projection position of the projected auxiliary light in the calibration mode set in the auxiliary light calibration mode setting step. A computer program for causing a computer to execute the method.

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