JPS6042460B2 - autofocus camera - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an automatic focusing camera, and more particularly to an automatic focusing camera that sets an objective lens to a focused position in accordance with a focal position signal obtained by optical scanning.

This type of automatic focusing camera is intended to free the camera user from the task of adjusting the focus.

In other words, the focus is adjusted automatically regardless of the user's intention. Configuring the camera in this way has the following disadvantages. (a) In the case of a subject that exceeds the focus position measurement ability, the focus must be uniquely determined.

(b) The central part of the screen becomes the subject of focus determination, which is inconvenient when trying to focus on other parts.

(c) Since the measurement adjustment is performed in a series of operations, it is not easy to confirm where the focus is before photographing.

Furthermore, even if this type of camera leaves room for the photographer's intentions to intervene, it is necessary that the operation be simple and that measurements and adjustments can be made reliably and quickly.

In addition, the focus adjustment mechanism is required to be simple, suitable for miniaturization, and lightweight.

An object of the present invention is to provide an automatic focusing camera that satisfies the above requirements.

To achieve the above object, the autofocus camera according to the present invention, according to the focus signal obtained by optical scanning,
In an automatic focusing camera that brings an objective lens to a focused position, the temporary setting ring is supported at the center of the optical axis of the camera, and the temporary setting ring is rotatably supported and rotation in a first direction is regulated by the temporary setting ring. lens ring and
a charging mechanism that charges the temporary setting ring and the lens ring by moving them in a second direction and applying a moving force in the first direction; a release mechanism that can release the temporary setting ring and then the lens ring; and the temporary setting. The apparatus includes a setting mechanism that locks the temporary setting ring in accordance with a focus signal while the ring is released and moving.

According to the above configuration, so-called temporary setting is possible and focus adjustment can be attempted as many times as desired, which is convenient when photographing a special subject or trying a special photographing technique.

In addition, since the lens position set can be separated into two stages, provisional setting and set, the inertia of the mechanism related to each set is divided, increasing the durability of the claw mechanism etc. for adjustment. Since mechanical advantages such as the ability to perform the following functions are obtained, and the operability is also excellent, the object of the present invention can be completely achieved. The camera according to the present invention will be described in more detail below with reference to the drawings.

1 to 4 are diagrams showing embodiments of the focus adjustment mechanism of the automatic focus adjustment camera according to the present invention, in which FIG. 1 shows the state before charging, FIG. 2 shows the state after charging, and FIG. The temporarily set state, FIG. 4, shows the set state, that is, the state in which the lens is set at the focal position.

In each figure, a fixed mirror 1 is a mirror for receiving light from the optical axis direction, and is fixed on a base plate 5 by a fixed mirror stand 3.

The scanning mirror 2 is a mirror that guides light from an image from an infinite direction to a close-up direction by swinging and rotating.
It is rotatably supported with respect to the bearing 6 by. The scanning interlocking plate 7 is fixed to the table 4, and the pin 8 provided at the other end is connected to a long hole provided in the temporary setting ring interlocking plate 9. The movement in the left and right directions in the figure is transmitted to the scanning mirror 2, and the mirror 2 is oscillated and rotated.

When the temporary setting ring interlocking plate is located on the right side in each figure, the mirror 2 receives light from the closest point, and when it is located on the left side, the mirror 2 occupies a position that receives light from an infinite point. The temporary setting ring interlocking plate 9 is urged leftward by a spring 10.

The interlocking plate locking pawl 11 is rotatably supported and the blade 12
The temporary setting ring interlocking plate 9 is biased clockwise by the locking member 9, and serves to hold the temporary setting ring interlocking plate 9 in the charging position.

The temporary setting ring 13 is rotatably supported on the outer periphery of the lens receiver 14, and is connected to the temporary setting ring interlocking plate 9 by a pin 30 fixed to an integrally provided arm portion 13a.
It is connected to a long hole provided in the.

The ring 13 is moved clockwise (the second direction in this embodiment) by moving the temporary set ring interlocking plate 9 to the right, and counterclockwise (the first direction in this embodiment) by moving the temporary set ring interlocking plate 9 to the left. rotated to The temporary setting ring 13 is integrally provided with a ratchet tooth portion 13b and a reset arm 31 for forming a temporary setting state, which will be described later.

Furthermore, a long hole 13c (see FIG. 1) in the circumferential direction is provided, and this portion cooperates with the lens ring 15. lens 1
A lens ring 15 holding the lens 6 is supported inside the lens receiver 14 so as to be rotatable forward and backward. The forward and backward movement of the lens ring 15 due to rotation is regulated by a cam groove 14a provided in the lens receiver 14 (see FIG. 1) and a communication pin 17 provided integrally with the lens ring 15. move forward when moved in the direction of
Retreats when moved in the direction of.

The signal pawl 19 is rotatably supported, a counterclockwise rotational force is applied by a spring 21, and a counterclockwise limit position is determined by a pin 20. When the electromagnet 22 is regulated by a signal to be described later, it rotates clockwise, and its tip can be connected to the ratchet teeth 13b of the temporary setting ring 13 described above. Lens retaining claw 23
is rotatably supported, and a counterclockwise rotational force is applied by a spring 24.

The levers 25 and 26 are rotatably supported by a shaft 27, and the counterclockwise rotation of the lever 26 is caused by the rotation of the lever 26.
5 as rotation in the same direction.
The release slide 28 has arms 28a and 28b and is movable in the vertical direction in the figure, and is given an upward return habit by a spring 29.

When the release slide 28 is pushed down against the spring 29, the arm 28a pushes the interlocking plate locking pawl 11 counterclockwise,
Arm 28b then connects to a pin provided at the free end of said lever 26, causing lever 26 to move in a counterclockwise direction. FIG. 5 is a circuit diagram showing an embodiment of a circuit related to automatic focusing of a camera according to the present invention.

This embodiment uses a focus detection module (AF module) 32 developed by Honeywell, Inc. in the United States. This module 32 photoelectrically compares the image captured by the optical scanning of the scanning mirror and the image from the fixed mirror, and sets the position where the correlation between these images is greatest to the focal position, and sets the scanning mirror 2 The focus signal is generated in synchronization with the movement of the lens.

The module 32 is connected to a power source 37 via a power switch 35.
connected to.

The output of the module 32 is connected to the gate of the thyristor 33, and the electromagnet 22 mentioned above is the load of the thyristor. Diode 34 is a protection diode. The switch 35 is a switch that is linked to the release slide 28 described above and is turned on immediately when the release slide 28 is slightly pressed. The switch 36 forming the circuit of the thyristor 33 is linked to the shutter mechanism of the camera, and is a switch that is turned on when the shutter is charged and turned off when the shutter release is completed.
The circuit operation in this embodiment is as follows. First, when the shutter of the camera is charged, the switch 36 is turned on, and the focal position is measured by optically scanning the scanning mirror from infinity to the near distance. When the switch 35 is on, the focus signal generated by the measurement is generated, turning on the thyristor 33 and energizing the electromagnet 22.

The operation of the camera according to the present invention configured as above will be sequentially explained. (Charging automatic focus adjustment) FIG. 1 shows a state in which all operations have been completed, and the charging process is from this state until reaching FIG. 2.

Note that optical scanning is performed during this process. When the temporary settling interlock plate 9 is moved from the position shown in FIG. 1 to the direction shown in FIG. 2 by a charge transmission mechanism (not shown), such as a camera winding mechanism, this movement is transmitted to the scanning mirror 2 via the scan interlock plate 7. optical scanning from infinity to the nearest point.

On the other hand, the temporary setting ring 13 connected to the temporary setting ring interlocking plate by a pin 30 is moved clockwise. This movement is performed simultaneously with the movement of the scanning mirror 2. The contact pin 17 installed in the lens ring 15 is pushed by the end of the elongated hole 13c of the temporary setting ring 13 and similarly rotates clockwise. Then, the charging process ends in a state in which the communication pin 17 and the temporary setting ring interlocking plate 9 are respectively locked by the lens locking pawl 23 and the interlocking plate locking pawl 11 (FIG. 2). In this state, the lens ring 15 and the temporary set ring 13 are fixed by the spring 18 and the spring 10, respectively, with sufficient moving force applied in the first direction.

At this time, the lens 16 is extended to the closest position to the front, as shown in FIG.

Also, during this charging process, the switches 35 and 36 shown in FIG. 5 are on, and the AF module 32 has finished measuring the focal position.

(From the first stage release mechanism to temporary setting) When the release slide 28 is pushed down from the charging position shown in FIG.
Push 1 counterclockwise.

When the pawl 11 separates from the temporary setting ring interlocking plate 9, the interlocking plate 9 starts moving leftward, and the temporary setting ring 13 starts moving counterclockwise, which is the first direction. The scanning mirror 2 is also rotated toward infinity, and when the scanning mirror 2 reaches the focal point detected in the previous scan, the AF module 32 sends a signal to the thyristor 33, and the electromagnet 22 is turned on by the conduction of the thyristor. is energized. When the electromagnet 22 is energized, the signal pawl 19 is coupled to the ratchet teeth 13b, as shown in FIG. 3, and prevents the temporary set ring 13 from rotating counterclockwise. The position of this temporary setting ring 13 indicates the focal position.

At this time, the lens 16 is still kept at a close position and no actual lens movement is performed. (From Temporary Set to Set State) When the release slide 28 is further pushed down from the temporarily set state shown in FIG. 3, 28b contacts the pin of the lever 26, causing the levers 26 and 25 to rotate counterclockwise.

Note that a click mechanism may be provided in relation to the release slide 28 so as to clearly distinguish between the start of the temporary setting, that is, the end of the release for the temporary setting, and the start of the release for the actual setting. can.

When the lens retaining pawl 23 is released from the communication pin 17 by the rotation of the levers 25, 26 by pressing down the release slide 28 after clicking, the lens ring 15 is rotated in the first direction by the force of the spring 18. The pin 17 hits the elongated hole 13c of the temporary setting ring 13 and is stopped (FIG. 4).

This position is the position where the lens position has been set.
Is it automatic focus adjustment by operating a shutter mechanism (not shown) by pressing down the release slide 28? Finish the shadow. (Re-temporary set after completion of temporary set)
If the above-described process is continued in one breath, normal automatic focus adjustment photographing can be performed instantaneously, but a case will be explained in which it becomes necessary to perform focus adjustment again as a result of temporary setting.

Such a request may occur, for example, when the subject has no contrast at all, or when an object in the center of the screen has been temporarily set, but this is inconvenient.

In the state where the temporary setting has been completed, the pin 17 provided on the lens ring 15 is in a state of being locked by the claw 23 due to the previous charging process, and the signal claw 19 is in the position shown in FIG. 3.

In this state, when the release slide 28 is returned to its original position by the force of the spring 29, the switch 35 is turned off, and the thyristor 3
3 is off, the pawl 19 separates from the ratchet teeth 13b, and the temporary set ring 13 returns to the position shown in FIG. In this state, the release slide 28 is slightly pushed down, the switch 35 is turned on, and the temporary set ring 13 shown in FIG.
By rotating the reset arm 31 provided integrally with the clockwise direction, re-optical scanning from infinity to close range is possible, and at the end of re-optical scanning, the temporary setting ring interlocking plate is attached to the interlocking locking pawl 11. It can be locked. In this state, the release slide 28 can be pushed down and the temporary setting can be attempted again.

This provisional setting can be performed any number of times. In this way, re-temporary setting becomes possible.

In order to notify the photographer of the temporary setting status, a line and code indicating the objective position are provided on the temporary setting ring, and if these are projected into the viewfinder optical system along with an index provided at a fixed position, shooting will be easier. person can identify inappropriate adjustments.

You can re-temporarily set it. Since the focal length adjusting device according to the present invention is configured as described above, it is possible to effectively utilize the state of pressing the release button halfway to try out various focus adjustments.

In other words, since the process of measuring and confirming the focus position (temporary setting) and the process of actual setting can be used separately, it is possible to set the focus temporarily, decide on the composition, and then shoot the actual set.

This is useful in cases where the field of view of the module is narrow and the image is set by the subject in the center, or when it is inconvenient to temporarily set the desired object and move the camera, or when the contrast of the subject is directional and the image is set as desired. This is extremely effective when it is difficult to adjust the focus in a composition where the camera is rotated 90 degrees, temporarily set, and then returned to set and release.

Various modifications can be made to the embodiments described in detail above within the scope of the present invention.

It is also possible to create a resettable state whenever the release lever returns, and to make the release temporarily set again when the release is pressed down again.

Furthermore, in the embodiment, a case is shown in which optical scanning is performed in the direction from infinity to the closest distance, but it may be configured so that optical scanning is performed in the direction of this limit and temporary setting is performed in the direction from infinity to the near distance. is also possible.

[Brief explanation of drawings]

1 to 4 are diagrams showing embodiments of the focus adjustment mechanism of the automatic focus adjustment camera according to the present invention, in which FIG. 1 shows the state before charging, FIG. 2 shows the state after charging, and FIG. Temporary set state, FIG. 4 shows the set state. FIG. 5 is a circuit diagram showing an embodiment of the automatic focus adjustment circuit. 1...Fixed mirror, 2...Scanning mirror, 3...Fixed mirror stand, 4...Scanning mirror stand,
5... Ground plate, 6... Bearing, 7...
...Scan interlocking plate, 8...Connection pin, 9...
...temporary set ring interlocking plate, 10...the same spring,
11... Interlocking plate locking claw, 12... Same spring, 13... Temporary setting ring, 14...
Lens holder, 15...Lens ring, 16...
... Lens, 17 ... Contact pin, 18 ... Lens drive spring, 19 ... Signal claw, 20 ...
・Zen, 21... Spring, 22... Electromagnet, 23... Luns stopper, 24... Same spring, 25, 26... Rubber, 27...Axis,
28... Release slide, 29... Same spring, 30... Connection pin, 31... Reset arm, 32... AF module, 33...
...Thyristor, 34 ...Diode, 3
5, 36...Switch, 37...Power supply.

Claims (1)

[Claims] 1. In an automatic focusing camera that brings an objective lens to a focused position according to a focus signal obtained by optical scanning, there is a temporary setting ring supported at the center of the optical axis of the camera, and a second ring supported rotatably back and forth. a lens ring whose rotation in one direction is regulated by the temporary setting ring; a charging mechanism that moves the temporary setting ring and the lens ring in a second direction and charges them by moving them in the first direction; The lens ring is characterized by being configured to include a release mechanism that can release the temporary setting ring and then the lens ring, and a setting mechanism that locks the temporary setting ring in accordance with a focus signal while the temporary setting ring is released and moving. Autofocus camera.