JP2568387B2 - Lens moving device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a lens moving device for moving a lens for setting a magnification.

[0002]

2. Description of the Related Art Conventionally, a lens that moves when setting a magnification depends on the magnification position of the lens when the movement starts.
There are a case where the camera stops at the newly set magnification position from the telephoto side and a case where it stops from the wide angle side.

[0003]

However, in the case of such a configuration, it is attempted to control the moving lens to stop at the same position when the moving lens stops from the telephoto side and when the moving lens stops from the wide-angle side. Actually, the lens cannot be accurately stopped at the same position due to the backlash, and there is a problem that the lens whose magnification is set cannot be positioned with high accuracy.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has been made to eliminate the effects of backlash at a magnification position to be set and to enable high-precision positioning of a photographing lens. It is an object of the present invention to provide a lens moving device that does not give an uncomfortable feeling or poor operability to a user.

[0005]

To achieve the above object, the present invention provides a magnification setting means, a photographing lens operating means for stopping a photographing lens from one direction to a magnification position set by the magnification setting means, The present invention is a lens moving device having a finder lens operating means capable of stopping a finder lens at a magnification position set by the magnification setting means from both a high magnification side and a low magnification side.

[0006]

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 schematically shows the movement of a photographing lens. 1 is a convex lens unit, 2 is a shutter blade also serving as an aperture, 3 is a concave lens unit, 4 is a photographing screen, and the drawing drawn on the upper side is short. FIG. 4 is a diagram showing a state in which the lens is focused on ∞ in a state of a focal length (hereinafter, referred to as WIDE), and a state in which the lower side is in a state of a long focal length (hereinafter, referred to as TELE) and the lens is in closest focus. Each of the lens units 1 and 3 for each rotation angle of the zoom ring, in which arrows C to H shown in the middle are drawn on the right side.
On the optical axis. That is, the arrows C to H indicate the movement progress (trajectory) of each lens group when the horizontal axis indicates the amount of movement of the lens and the vertical axis indicates the rotation angle of the zoom ring.

In this example, the concave lens unit 3 moves in a complicated manner. This will be described later, but it is actually possible with a very simple configuration.

First, in the WIDE of the above figure, the lens focus is ∞
When the zoom ring is rotated by 30 ° from the state where the zoom lens is in position, the convex lens unit 1, the shutter 2, and the concave lens unit 3 move integrally as shown in the figure. For this reason, there is no change in the magnification of the photographing lens system during the arrow D, and the focus is adjusted in the WIDE state by the rotation of the zoom ring, and the lens focus is brought to the closest distance at the position of 30 °. .

When the photographer wants to increase the magnification a little more and switches to a normal (hereinafter referred to as NOM) mode, the zoom ring stops at a position between 90 ° and 135 ° based on the distance measurement information.

That is, as already apparent, when the rotation of the zoom ring reaches 90 °, the NOM state (TE
In the state of the intermediate magnification between LE and WIDE), the lens position is focused on ∞.

When the zoom ring is further rotated from this state, the entire lens system is extended for 45 ° as in the case of WIDE, and focus adjustment is performed in the NOM state.

In the case of TELE, the zoom ring is similarly set to 18
When the lens is turned by 0 °, the lens focus comes to the position where ∞ matches with ∞, and when the zoom ring is further rotated, the TEL
The lens position is such that the lens is in focus at a short distance in the E state.

Therefore, with such a configuration, magnification adjustment and focus adjustment can be performed only by rotating a single zoom ring.

FIG. 2 shows a focal length of 35 mm to 70 mm.
FIG. 7 is a lens configuration diagram of a camera that can be switched to the above-described configuration, in which a photographic lens system is capable of switching seven focal lengths between 35 mm and 70 mm.

In FIG. 2, since the lens configuration is the same as that of FIG. 1, the same reference numerals as in FIG. 1 are used and only the operation will be described. The upper diagram is a diagram when the lens system is 35 mm.
The zoom ring has already been rotated by 60 °, and at the retracted position of the zoom ring of 0 °, the front convex lens unit 1 is in a retracted state. When the zoom ring is 60 °, it is 35mm and the lens focus is set to ∞. If you turn the zoom ring further from this position, it will behave like a full extension, and the rotation of the zoom ring will reach 100 °. Is used for focus adjustment.

As described above, from the solid line portion to the dotted line portion where the respective focal lengths are written, the magnification adjustment is performed from the dotted line portion to the solid line portion within the range used for focus adjustment from ∞ to the close distance with the focal lengths unchanged. Range.

FIG. 2 differs from FIG. 1 in that the convex lens unit 1 also moves in a discontinuous manner and that the number of switching points is increased by increasing the rotation angle of the zoom ring.

Note that it is also easy to perform focus adjustment only by the movement of the front group or the rear group without performing the entire extension.

FIGS. 3 and 4 specifically show the configuration of FIG. 2. 1 and 3 are the convex lens unit and the concave lens unit shown in FIG. 2, 1a is a convex lens frame, 1b
Is a notch provided in the convex lens frame 1a, and 1c is a pin that fits into a rectilinear groove 5b of the fixed frame 5 described later and fits into the lead cam groove 6b of the zoom ring 6. 3a is a concave lens frame, 3b is a projection of the concave lens frame 3a, and 3c is also a rectilinear groove 5b of the fixed frame 5 and a lead cam groove 6c of the zoom ring 6.
This is a pin that fits. The cam grooves 6b and 6c form the trajectories of the lens units 1 and 2 as shown by arrows in FIG. Further, the outer peripheral portion of the lens frame 1a and the lens frame 3a is slidably fitted to the inner peripheral portion of the fixed frame 5 described later.

Reference numeral 5 denotes a fixed frame.
a, 3a, and an outer peripheral portion 5a is provided with a zoom ring 6 described later.
And a straight groove 5b parallel to the optical axis.
Are cut, and the above-mentioned pins 1c and 3c
Are fitted.

In this example, two pins 1 are inserted into one groove 5b.
Although c and 3c are fitted, they may be fitted in separate grooves.

Numeral 6 denotes a zoom ring whose inner diameter 6a is fitted to the outer peripheral portion of the fixed frame 5 and is rotatably supported. The zoom ring 6 has a lead cam groove 6b for the convex lens unit 1 and a concave lens unit 3.
And a contact piece or terminal 6d for transmitting rotation of the cam ring 6 to a pulse plate 9 described later.
The gear portion 6e meshes with the gear 7.

The gear 7 is rotatably supported by a shaft 7a, and the gear 7b is engaged with the gear 6e of the zoom ring 6 at the same time as the motor 8 through a known reduction gear train.
It is linked with.

Reference numeral 9 denotes a pulse plate having a pattern formed on the surface of a donut disk, and reference numeral 10 denotes a pulse detection circuit.

Reference numeral 11 denotes a motor control circuit, which is a motor forward rotation energizing circuit based on the output of the comparator 12a.
The output of the comparator 12b forms a motor reverse rotation energizing circuit.

Reference numeral 13 denotes an arithmetic circuit for rotating the zoom ring.
Subject distance detection circuit 14 and zooming signal processing circuit 1
The operation shown in Table 1 is performed on the basis of the signal from No. 5.
Reference numeral 16 denotes a logic control circuit which puts the motor forward rotation circuit of the motor control circuit 11 into an operation ready state when the photographer presses the first stroke of the release button. When the release of the release button is interrupted, the logic control 16 puts the motor reversing circuit of the motor control circuit 11 into an operation ready state.

The subject distance detection circuit 14 digitizes the subject distance information obtained from the distance measuring module 17 and inputs it to the arithmetic circuit 13.

[0029]

[Table 1]

Numeral 18 denotes a zooming operation member for continuously changing the magnification during f = 35 mm to 70 mm, for example.
Each position signal is processed by the zooming signal processing circuit 15, and the processing circuit 15 converts the position signal into a numerical value of 10 to 70 as shown in Table 1 and inputs the numerical value to the zoom ring rotation operation circuit 13. Also, a zooming operation member 1
Reference numeral 8 functions to operate the finder lens moving mechanism 19.

When the power switch is turned on by the photographer pressing the release button to the first stroke, the logic control circuit 16 issues an activation signal to the distance measuring module 17 and further waits for the distance measuring operation to be completed sufficiently. Then, a motor start signal is issued to the motor control circuit 11.

FIGS. 5A and 5B are FIGS. 3 and 4 respectively.
3 shows details of a zooming operation member 18 and a finder lens moving mechanism 19 shown in FIG.
Is a movable lens, 23 is an eyepiece, and the movable lens 22 has a zoom pin 22a, which is supported by a known method so as to be movable in the left and right directions in the figure. It is urged and is in contact with an idling portion 24c of a zooming cam lever 24 described later.

Numeral 24 denotes a zooming cam lever having a long hole 24a.
Are supported by the pins so as to be slidable in the up-down direction in the figure, and a cam portion 24b, an idling portion 24c,
It has an end face portion 24d, and has a zooming operation knob 25 described later.
, And a spring (not shown) urged upward in the figure is engaged.

Reference numeral 25 denotes a zooming operation knob operated by a photographer, which is slidably supported in a known manner by a known technique so as to be slidable up and down in the figure.
At the lower end 25a, the end 24 of the zoom cam lever 24
It has a brush 25b that slides integrally when pressing d.

Numeral 26 denotes a resistor pattern formed on a substrate (not shown), which is rotatably connected as shown in FIG. 6 from above in the figure, and the brush 25b of the zooming operation knob 25 slides on the resistor pattern 26. To generate a position signal of the zooming operation knob 25.

FIG. 7 is a detailed view of the zooming signal processing circuit 15 shown in FIGS. 3 and 4, wherein reference numeral 31 denotes a power source, 32 denotes a switch linked to a release button, and 33 denotes the resistor pattern 26 and the brush 25b. The variable resistor 34 is a voltage detecting circuit for converting the resistance value of the variable resistor 33 into a voltage, and the voltage converting circuit 35 converts the voltage value of the voltage detecting circuit 34 into a signal as shown in Table 1 to generate a zoom ring. Rotation operation circuit 13
An AD conversion circuit for sending to the

Next, the operation of the above configuration will be described.

The photographer holds the camera and looks into the finder, operates the operation knob 25, moves the cam lever 24, moves the movable lens 22, and sets the magnification of the finder. At the same time, the brush 25b slides on the resistance pattern 26, and the resistance value of the variable resistor 33 is set. In this state, when the photographer presses the release button up to the first stroke, the power switch is turned on. First, a distance measurement operation is performed by the distance measurement module 17 based on a signal of the logic control circuit 16, and a signal is transmitted to the object distance detection circuit 14. The digital signal is sent to the zoom ring rotation operation circuit 13 and digitized. When the switch 32 is closed, a voltage corresponding to the resistance value of the variable resistor 33 is output from the voltage detection circuit 34 and digitized by the AD conversion circuit 35. This digital signal is applied to the zoom ring rotation operation circuit 13 as an output of the zooming signal processing circuit 15. The operation circuit 13 performs an operation as shown in Table 1 according to the outputs of the circuits 14 and 15. For example, if the switching position of the zooming operation means 16 is a position of f = 50 mm at a position where the object distance is 4 m, and as shown in Table 1, the numbers of the two are combined and 41 numbers are stored, and this is stored as a reference value of the comparator 12a. I do.

The motor control circuit 11 rotates the motor 8 in a forward direction according to a signal from the logic control circuit 16 and rotates the zoom ring 6 from WIDE toward the TELE direction. The rotation of the zoom ring 6 is performed by the pulse plate 9
The pulse is output as a pulse, detected by the pulse detection circuit 10 and applied to the comparator 12. At this time, up to 10 pulses are issued when the lens units 1 and 3 extend the lens from the storage position to the position in FIG.

When the motor 8 rotates in the forward direction, a position signal is generated one after another. When the number of pulses reaches 41, the comparator 12a is inverted to generate an end signal. The motor control circuit 11 short-circuits both ends of the motor 8. The electric brake is applied to the motor 8 to stop it.

At this time, the amount of rotation of the zoom ring 6 is about 260 ° according to FIG. Thereafter, when the photographer presses the release button to the second stroke, a known exposure operation is performed, and when the release button returns, the motor 8
Is reversed by the motor control circuit 11 according to a command from the logic control circuit 16, and the zoom ring 6
Rotates in the WIDE direction and returns to the initial position, the switch SW turns off, the comparator 12b reverses, and the motor 8 stops. Then, the film is wound up by one frame by a known winding means, and is in a state before the release button is pressed again.

In the above embodiment, seven points are switched between 35 and 70 mm. However, the number of points can be increased or decreased, and the same operation can be performed.

In the above embodiment, the pulse plate 9 and the pulse detection circuit 10 are provided to detect the position of the photographing lens and determine the stop time of the motor 8, but the present invention is not limited to this. Alternatively, a pulse motor may be used as the motor 8, and the position of the photographing lens may be determined by rotating the pulse motor according to the number of output pulses from the arithmetic circuit 13. By doing so, the pulse plate 9,
There is no need for the pulse detection circuit 10 and the comparator 12a,
What is necessary is just to make the output of the arithmetic circuit 13 directly input to the motor control circuit 11.

(Correspondence between Invention and Embodiment) In the above embodiment, the zooming signal processing circuit 15
The zooming operation member 18 is a magnification setting means of the present invention, and the pulse plate 9, the pulse detection circuit 10, the motor control circuit 11, the comparator 12a, and the zoom ring rotation calculating circuit 13 are a finder lens moving mechanism of the present invention. 19 corresponds to the finder lens operating means of the present invention.

[0045]

As described above, according to the present invention, by stopping the photographing lens at a set magnification position from one direction, the magnification setting of the photographing lens can eliminate the effect of backlash and achieve high precision. In addition, the finder lens can be stopped at both the high magnification side and the low magnification side at the set magnification position, so that a user looking through the finder does not feel uncomfortable or poor operability. Things.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing the movement of a taking lens according to an embodiment of the present invention.

FIG. 2 is a schematic view showing the movement of a photographing lens according to an embodiment of the present invention.

FIG. 3 is a detailed diagram specifically showing a configuration for performing the operation of FIG. 2;

FIG. 4 is a diagram showing a state in which the configuration of FIG. 3 is changed from a wide-angle side to a telephoto side.

FIG. 5A is a detailed view of a finder section shown in FIG. 3,
(B) is a detailed view of the finder section also shown in FIG.

FIG. 6 is a detailed diagram of the zooming signal processing circuit shown in FIGS. 3 and 4;

[Explanation of symbols]

 Reference Signs List 1 convex lens unit 3 concave lens unit 6 zoom ring 7 gear 8 motor 9 pulse plate 10 pulse detection circuit 11 motor control circuit 12a, 12b comparator 13 zoom ring rotation operation circuit 14 subject distance detection circuit 15 zooming signal processing circuit 16 control circuit 17 Distance measuring module 18 Zooming operation member 19 Viewfinder lens moving mechanism

Claims (1)

(57) [Claims] 1. Magnification setting means, photographing lens actuating means for stopping a photographing lens from one direction to a magnification position set by the magnification setting means, and raising a finder lens to a magnification position set by the magnification setting means. A lens moving device comprising: a finder lens actuating means that can be stopped from both the magnification side and the low magnification side.