JPH052211A - Focusing lock device for camera - Google Patents

Abstract

PURPOSE:To consecutively photograph plural objects and to keep the storage of focusing lock by individually executing the focusing lock to the plural objects in a photographic image plane. CONSTITUTION:When a storing mode is selected by a focusing lock mode setting switch 104, a storing mode selection signal is transmitted to an arithmetic circuit 101. Continuously, by half-depressing a release button 103, the arithmetic circuit 101 transmits a signal to a motor control circuit 106 based on a defocusing signal from a focusing detection circuit 102 so that a lens 108 is driven by a motor 107. When the focusing detection circuit 102 detects the focusing state, the arithmetic circuit 101 transmits a lens stopping signal to the motor control circuit 106 so that the lens 108 is stopped. Information on a lens position at such a time is stored in a memory 109. In a photographing mode, a signal is transmitted to the motor control circuit 106 according to the number selected by a focusing lock position selecting switch 105 so as to drive the lens 108.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a focus lock device for a camera.

[0002]

2. Description of the Related Art When shooting with an autofocus camera that has only one distance measuring area in the center of the shooting screen, if the subject is not in the center of the shooting screen, first try to catch the subject in the distance measuring area in the center of the shooting screen. It is a normal photographing method to perform shutter release after laying out a photographing screen by changing the direction of the camera while operating the focus lock function after measuring the distance with the camera pointing.

Further, for example, according to the technique disclosed in Japanese Patent Application Laid-Open No. 1-279215, there is a distance measuring means capable of separately measuring object distances corresponding to a plurality of points on a photographing screen. Also, a camera has been proposed in which the photographer selects a desired distance measurement area from among them so as to minimize the change of the layout of the photographing screen.

However, in the prior art, when there is one distance measuring area, the subject has to be put into the distance measuring area every time one frame is photographed, and the photographing angle of view must be changed. Therefore, there is a drawback in that a plurality of subjects having different distances are present in the same photographing screen, and a shutter chance is missed when a photograph in which each subject is in focus is desired to be taken.

To reduce the change of the angle of view, Japanese Patent Laid-Open No. 1-27
Providing a plurality of distance measurement areas in the photographing screen by the technique disclosed in Japanese Patent No. 9215 causes the mechanism of the camera to be complicated, and it is difficult to actually cover the entire photographing screen. Further, in the prior art, when it is desired to photograph a subject once photographed again, the distance must be newly measured, which is not suitable for repeated photographing.

[0006]

In order to solve the above-mentioned problems, the present invention makes it possible to continuously perform focus lock individually for a plurality of subjects within a photographing screen until the next shutter release. Another object of the present invention is to provide a focus lock device for a camera in which the memory of the focus lock remains even after the shutter release.

[0007]

According to the present invention, there is provided focus detection means 102 for detecting a focus for measuring a subject distance.
Storage means 104, 109 capable of storing a plurality of distance measurement information obtained by the focus detection means 102, and selection means 10 for selecting one of the distance measurement information stored by the storage means.
5, the lens driving means 106 and 107 for driving the lens 108 to a predetermined position based on the distance measuring information selected by the selecting means 105, and the distance measuring information selected by the selecting means 105. Display means 1 for displaying
A focus lock device for a camera, which is characterized in that the focus lock device is provided with 10, 111.

[0008]

[Function] It is possible to individually perform focus lock on a plurality of subjects within the photographing screen. The focus lock memory remains even after the shutter release. One distance measurement area should be owned in the center of the shooting screen.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIGS. 1 to 3, 5 and 6. FIG. 1 is a block diagram showing the basic configuration of an embodiment of the present invention. FIG. 2 is a flowchart showing the processing procedure of the arithmetic circuit. FIG. 3 is a diagonal rear view of a camera in which this embodiment is used. FIG. 5 is a view showing the display in the viewfinder of the camera using this embodiment. FIG. 6 is a diagram showing the correspondence between the display of the display device using this embodiment and the focus mode.

First, the structure will be described with reference to FIG. The arithmetic circuit 101 is a C mounted on the camera for performing various arithmetic operations of the camera.
It is PU. The focus detection circuit 102 is a circuit for measuring the subject distance. The release button 103 is a button for shutter release. The focus lock mode setting switch 104 is a switch for setting the camera to the focus lock mode, and the focus lock mode includes a storage mode and a shooting mode. The focus lock position selection switch 105 is a switch for selecting a position on the photographing screen to be focus locked. The motor control circuit 106 is a circuit that controls the motor 107. Motor 1
A motor 07 drives the lens 108. Lens 1
Reference numeral 08 is a focusing lens. The memory 109 is a memory that stores information on the stop position of the lens 108 according to the distance measurement information when the focus lock mode is set.
The display circuit 110 is a display circuit which controls the display device 111. The display device 111 is a display device that displays the focus lock number in the finder.

Next, the operation of the focus lock will be described with reference to FIG.
Will be described. When the storage mode is selected by the focus lock mode setting switch 104, the arithmetic circuit 10
A storage mode selection signal is sent to 1. Then, when the release button 103 is half-pressed, the arithmetic circuit 101 sends a signal to the motor control circuit 106 based on the defocus signal from the focus detection circuit 102, and the motor 107 causes the lens 10 to operate.
8 is driven. When the focus detection circuit 102 detects the in-focus state, the arithmetic circuit 101 sends a lens stop signal to the motor control circuit 106 to stop the lens 108. Information on the lens position at this time is stored in the memory 109.

Focus lock mode setting switch 10
When the photographing mode is selected by 4, the photographing mode selection signal is sent to the arithmetic circuit 101. Then release button 10
When 3 is pressed halfway, the arithmetic circuit 101 reads out the information of the corresponding lens position from the memory 109 according to the focus lock number selected by the focus lock position selection switch 105 and sends a signal to the motor control circuit 106 to move the lens 108 to a predetermined position. To drive. The focus lock number is displayed on the display device 111 via the display circuit 110.

The operation of the focus lock will be described with reference to FIG. FIG. 2 is a flowchart showing the processing procedure of the arithmetic circuit 101. First, in step S20, it is determined whether or not the focus lock mode is set.
When affirmative, it progresses to step S21. If denied, return to return. In step S21, it is determined whether or not the focus lock mode is selectively set to the storage mode. When affirmative, it progresses to step S22. When denied, it will progress to step S29. In step S22, it is determined whether the release button 103 is half pressed. When affirmative, it progresses to step S23. When denied, it will return to step S20.

Distance measurement is performed in step S23, and the flow advances to step S24. Lens 1 in step S24
08 is driven, and the process proceeds to step S25. Step S2
In step 5, it is determined whether or not it is in focus. If affirmative, it will progress to step S26. When denied, it will return to step S22. The motor 107 is stopped in step S26, and the process proceeds to step S27. In step S27, the lens position is stored in the memory 109, and in step S28
Proceed to. In step S28, the state of the release button 103 is determined. If it is half-pushed, step S2
Repeat 8. If not pressed, step S
Returning to step 21, steps S22 to S27 are repeated. By repeating this, a plurality of lens positions can be stored in the memory 10.
9 can be stored. If the release button 103 is fully pressed in step S28, step S34
Proceed to. In step S34, the release operation is performed.

In step S21, it is determined whether or not the focus lock mode is selectively set to the storage mode. If the focus mode is not the storage mode but the photographing mode, the determination is negative, the process proceeds to step S29, and the focus lock is randomly performed in the storage mode. The lens position data is rearranged in order of distance, and the process proceeds to step S30. In step S30, it is determined whether the release button 103 is half pressed. When affirmative, it progresses to step S31. When denied, it will return to step S20. In step S31, the focus lock number selected by the focus lock position selection switch 105 is checked, and the data of the corresponding lens position is read from the memory 109. Then, the process proceeds to step S32. In step S32, step S
The motor control circuit 106 based on the data read in 31.
To drive the lens 108 and stop it at a predetermined focus lock position. Then, the process proceeds to step S33. In step S33, it is determined whether the release button 103 is fully pressed. If affirmative, step S
Proceed to 34. When denied, it will return to step S30. After the release operation is performed in step S34, the process returns to step S20.

Next, operation members and displays will be described with reference to FIGS.
6 and FIG. FIG. 3A is a rear perspective view of a camera equipped with this embodiment. A dial 12 is provided on the upper left portion of the rear surface of the camera 11. Dial 12
Also serves as the focus lock mode setting switch 104 and the focus lock position selection switch 105. A button 13 is provided on the right side of the upper surface of the camera 11. Button 1
Reference numeral 3 is a release button 103.

FIG. 3B is an enlarged view showing the dial 12 in an enlarged manner. The dial 12 is rotatably supported by the camera 11. Index "-" 12a, index "+" 12
b is an index indicating the rotating direction of the dial 12. There are the number of focus lock positions and the number of set positions that is the sum of the AF mode and the focus lock storage mode. The number of focus lock positions is 5 in this embodiment. Generally, 5 to 7 is suitable.

Next, the display member of the first embodiment will be described with reference to FIG.
Will be described. FIG. 5 is a view showing the finder display of this embodiment. The field of view is displayed on the shooting screen 15 in the finder frame. The number of the subject whose focus is locked, that is, the focus lock number is displayed numerically on the display unit 14 at the lower right of the shooting screen 15 outside the viewfinder frame. The display unit 14 corresponds to the display device 111.

Since the focus lock numbers are rearranged in step S29 in the order of the subject distance, the smaller number means the closer distance, and the larger number means the farther. Person 15
a, a few people 15b, low trees 15c, high trees 15d, mountain 1
5e are subject distances of 5 m, 10 m, 15 m and 20 respectively.
m, infinity, the numbers 1, 2, 3, on the display unit 14
4 and 5 are a person 15a, a small person 15b, and a low tree 1 respectively.
5c, high trees 15d, and mountains 15e are in focus. Select focus lock number and press button 13 (10
When 3) is pressed halfway, the lens is driven and the focus is locked at the corresponding position.

Next, the relationship among the dial 12, the display unit 14, and the photographing mode will be described with reference to FIG. FIG. 6 is a diagram illustrating the relationship between the dial 12, the display unit 14, and the shooting mode. The normal AF mode, the focus lock storage mode, and the focus lock shooting mode are sequentially selected by the dial 12. Dial 12 is the most "-" 12
On the a side, the display is "0", which is the normal AF mode. When the dial 12 is next to the index “−” 12a side, the display is “−−”, which is the focus lock storage mode.
When the dial 12 next approaches the index "+" 12b side, the display becomes "1" to "5", which is the focus lock photographing mode. The display "1" is the closest and "5" is the farthest.

Next, the operation member of the second embodiment will be described with reference to FIG.
Will be described. FIG. 4A is a rear perspective view of a camera equipped with the second embodiment. Two buttons 12c and 12d are provided on the left part of the upper surface of the camera 11. Two buttons 1
2c and 12d are focus lock mode setting switches 1
04 and a focus lock position selection switch 105. FIG. 4B is an enlarged view showing the buttons 12c and 12d in an enlarged manner. Indicators "-" and "+" are attached to the buttons 12c and 12d, and by pressing these, the display and the function are changed in the same manner as described in FIG. The other parts and operations are the same as those in the first embodiment, and the description is omitted.

[0022]

As described above, according to the present invention, it is possible to individually perform focus lock on a plurality of subjects within a photographing screen, so that a plurality of subjects can be continuously photographed. Since the focus lock memory remains even after the shutter release, it is not necessary to measure the distance each time the shutter is released when repeatedly shooting, which is particularly effective for a subject having low brightness and low contrast. Since the distance measuring area only needs to be owned in the center of the shooting screen, the mechanism is simple.

[Brief description of drawings]

FIG. 1 is a block diagram showing a basic configuration of a first exemplary embodiment of the present invention.

FIG. 2 is a flowchart showing a processing procedure of an arithmetic circuit of the first embodiment.

FIG. 3A is an oblique rear view of a camera in which this embodiment of the first embodiment is used. (B) is an enlarged view showing the dial 12 in an enlarged manner.

FIG. 4A is a perspective view of a focus lock mode setting switch according to a second embodiment of the present invention. (B) is an enlarged view showing the dial 12 in an enlarged manner.

FIG. 5 is a view showing a display in a viewfinder of a camera using this embodiment of the first embodiment.

FIG. 6 is a diagram showing a correspondence between a display and a focus mode of a display device using this embodiment of the first embodiment.

[Explanation of symbols]

 101 arithmetic circuit 102 focus detection circuit 103 release button 104 focus lock mode setting switch 105 focus lock position selection switch 106 motor control circuit 107 motor 108 lens 109 memory 110 display circuit 111 display device 11 camera 12 dial 12a, 12b index 12c, 12d button 13 button 14 display 15 shooting screen

Claims (1)

Claim: What is claimed is: 1. A focus detection means for detecting a focus for measuring a subject distance in a region of one point in a photographing screen,
Storage means capable of storing a plurality of distance measurement information obtained by the focus detection means, selection means for selecting one of the distance measurement information stored by the storage means, and distance measurement selected by the selection means A focus lock device for a camera, comprising: a lens driving means for driving the lens to a predetermined position based on the information; and a display means for displaying which distance measurement information selected by the selection means is. ..