JPH07151954A - Variable power lens controller - Google Patents

Abstract

PURPOSE:To reduce load required for manufacture and to reduce a cost by stopping a lens unit stepwise according as the designation to continuously change zoom magnifications. CONSTITUTION:As for a camera constituted so that both of a magnification adjusting action and a focusing action can be executed only by rotating a single zoom right 6; the magnification is continuously changed within a lens focal distance 35mm-70mm, for example, by a zooming operation part 18 and the respective position signals thereof are processed by a zooming signal processing circuit 15. By the processing circuit 15, the position signal is digitized to 7 steps and inputted to a zoom ring rotation arithmetic circuit 13. Then, arithmetic operation is executed according to the outputs of an object distance detection circuit 14 and the processing circuit 15 by the arithmetic circuit 13 and a motor 8 is rotated forward by a motor control circuit 11. Besides, the ring 6 is rotated to the direction of a long focal distance(TELE) from a short focal distance(WIDE) until the calculated value is obtained and the lens units 1 and 3 are extended.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a variable power lens control device for controlling the movement of a variable power lens.

[0002]

2. Description of the Related Art Conventionally, when changing the zoom magnification of a zoom lens, the magnification of the zoom lens is also changed continuously in response to an instruction to change the zoom magnification continuously from the operating means. .

[0003]

However, in the case of such a configuration, the zoom lens must be capable of setting the magnification over the entire zoom region, and therefore a high precision cam mechanism or the like is required over the entire zoom region. However, there is a problem that the load required for manufacturing is large and the cost is increased.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a variable power lens control device capable of reducing the load required for manufacturing and reducing the cost.

[0005]

According to the present invention, there is provided a lens unit, drive means for driving the lens unit, zoom magnification change instruction means for instructing continuous change of zoom magnification, and the drive means. A variable power lens control device having a control unit that drives the lens unit and stops the lens unit stepwise in response to a continuous zoom magnification change instruction from the zoom magnification change instruction unit. is there.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic view of the movement of a photographing lens. 1 is a convex lens unit, 2 is a shutter blade that also serves as an aperture, 3 is a concave lens unit, 4 is a photographing screen, and the upper drawing is short. The figure shows a state in which the lens focus is set to ∞ in the focal length (hereinafter referred to as WIDE) state, and the lower side is a long focal length (hereinafter referred to as TELE) state and the lens focus is set to the closest point. , The arrows C to H shown in the middle are drawn on the right side, and the respective lens units 1 and 3 for the respective rotation angles of the zoom ring.
Represents the position on the optical axis of. That is, the arrows C to H indicate the movement process (trajectory) of each lens group when the horizontal axis represents the amount of lens movement and the vertical axis represents the rotation angle of the zoom ring.

In this example, the concave lens unit 3 makes complicated movements. This will be described later, but in reality, it is possible with a very simple structure.

First, the lens focus is ∞ in WIDE in the above figure.
When the zoom ring is rotated by 30 ° from the state of matching, the convex lens unit 1, the shutter 2, and the concave lens unit 3 move integrally as shown in the figure. For this reason, the magnification of the taking lens system does not change between the arrows 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 the mode is switched to the 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 intermediate magnification state between LE and WIDE), the lens position is in focus at ∞.

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

Similarly, at the time of TELE, the zoom ring is set to 18
When it is rotated 0 °, the lens focus comes to ∞ with TELE, and when the zoom ring is further rotated, it becomes TEL.
The lens position is such that the lens is in the E state and is in focus at a short distance.

Therefore, with such a structure, the magnification and the focus can be adjusted only by rotating the single zoom ring.

FIG. 2 shows a focal length of 35 mm to 70 mm.
In the lens configuration diagram of the switchable camera, the focal lengths of seven points can be switched between 35 mm and 70 mm in the taking lens system.

In FIG. 2, since the lens structure is the same as that of FIG. 1, the same reference numerals as those in FIG. 1 are given 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 the front convex lens unit 1 is retracted at the retracted position of the zoom ring 0 °. When the zoom ring is 60 °, it is 35 mm at the position where the lens focus is at ∞, and when the zoom ring is further rotated from there, it will move like an entire extension, and the amount of rotation of the zoom ring will reach the position of 100 °. Is used for focus adjustment.

As described above, from the solid line portion where each focal length is written to the dotted line portion, the magnification is adjusted from the dotted line portion to the solid line portion within the range used for focus adjustment from the infinity to the close-up distance as they are. Is the range used for.

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

It is also easy to perform the focus adjustment only by moving the front group or the rear group, without performing the entire focus adjustment.

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, and 1b is a convex lens frame.
Is a notch provided in the convex lens frame 1a, and 1c is a pin which fits in a rectilinear groove 5b of the fixed frame 5 described later and fits in a lead cam groove 6b of the zoom ring 6. Reference numeral 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.
It is a pin that fits with. These cam grooves 6b and 6c form the loci of the lens units 1 and 2 as shown by the arrows in FIG. The lens frame 1a and the lens frame 3a are slidably fitted at their outer peripheral parts to the inner peripheral part of the fixed frame 5 described later.

Reference numeral 5 denotes a fixed frame, the inner peripheral portion of which is the above-mentioned lens frame 1.
The outer peripheral portion 5a is fitted with the zoom ring 6 which will be described later.
The straight groove 5b that is fitted to the inner diameter portion 6a of the
Is cut, and the above-mentioned pins 1c and 3c are provided in the straight groove 5b.
Are fitted.

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

Reference numeral 6 denotes a zoom ring, the inner diameter 6a of which is fitted to the outer peripheral portion of the fixed frame 5 and is rotatably supported, and the lead cam groove 6b for the convex lens unit 1 and the concave lens unit 3 are provided.
Has a lead cam groove 6c for use with a contact plate or a terminal 6d for transmitting the 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 the shaft 7a, and the gear portion 7b meshes with the gear portion 6e of the zoom ring 6 described above.
It is interlocked with.

Reference numeral 9 is a pulse plate having a pattern formed on the surface of a donut-shaped disk, and 10 is a pulse detection circuit thereof.

Reference numeral 11 denotes a motor control circuit, which is a current-carrying circuit for forward rotation of the motor according to the output of the comparator 12a.
The output of the comparator 12b is configured to form a motor reverse rotation energizing circuit.

Reference numeral 13 is an arithmetic circuit for rotating the zoom ring.
Subject distance detection circuit 14 and zooming signal processing circuit 1
With the signal from 5, the calculation as shown in Table 1 is performed.
Reference numeral 16 denotes a logic control circuit, which makes the motor forward rotation circuit of the motor control circuit 11 ready for operation when the photographer presses the first stroke of the release button. When the release button operation is cut off, the logic control 16 puts the motor reversing circuit of the motor control circuit 11 into a ready state for operation.

The subject distance detecting 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]

Reference numeral 18 denotes a zooming operation member for continuously changing the magnification between f = 35 mm and 70 mm, for example.
Each position signal is processed by the zooming signal processing circuit 15, and the processing circuit 15 digitizes the position signal to 10 to 70 as shown in Table 1 and inputs it to the zoom ring rotation calculation circuit 13. Also, the zooming operation member 1
Reference numeral 8 serves to operate the finder lens moving mechanism 19.

When the photographer presses the release button up to the first stroke to turn on the power switch, the logic control circuit 16 issues a start signal to the distance measuring module 17 for a time sufficient to complete the distance measuring operation. After that, a motor start signal is issued to the motor control circuit 11.

FIGS. 5A and 5B are shown in FIGS.
The details of the zooming operation member 18 and the finder lens moving mechanism 19 shown in FIG.
Is a movable lens, 23 is an eyepiece lens, and the movable lens 22 is provided with 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, but by a spring (not shown) in the left direction in the figure. It is biased and abuts on an idling portion 24c of a zooming cam lever 24, which will be described later.

Reference numeral 24 is a zooming cam lever, which is an elongated hole 24a.
Is supported by the pin of FIG. 1 so as to be slidable in the vertical direction in the figure, and includes a cam portion 24b, an idling portion 24c,
It has an end face portion 24d and has a zooming operation knob 25 described later.
It is configured to be pushed by the end portion of the, and has a spring (not shown) biased upward in the drawing.

Reference numeral 25 denotes a zooming operation knob operated by a photographer, which is supported by a known technique so as to be slidable in the vertical direction in the figure with a proper friction,
The lower end 25a is provided at the end 24 of the zoom cam lever 24 described above.
It has a brush 25b that slides integrally when pressing d.

Reference numeral 26 denotes a resistor pattern formed on a substrate (not shown), which is rotationally connected as shown in FIG. 6 from above in the figure, and the brush 25b of the above-mentioned zooming knob 25 slides on the resistor pattern 26. It moves to cause a short circuit, and a position signal of the zooming operation knob 25 is generated.

FIG. 7 is a detailed view of the zooming signal processing circuit 15 of FIGS. 3 and 4, in which 31 is a power source, 32 is a switch linked to a release button, 33 is the resistor pattern 26 and the brush 25b. A variable resistor, 34 is a voltage detection circuit for converting the resistance value of the variable resistor 33 into a voltage, and 35 is a zoom ring by converting the voltage value of the voltage detection circuit 34 into a signal as shown in Table 1. Rotation calculation circuit 13
It is an AD conversion circuit for sending to.

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

The photographer holds the camera and looks into the viewfinder, operates the operation knob 25 to move the cam lever 24 and the movable lens 22, and sets the magnification of the viewfinder. At the same time, the brush 25b slides on the resistance pattern 26, and the resistance value of the variable resistor 33 is set. When the photographer pushes the release button to the first stroke in this state, the power switch is turned on, and the distance measuring module 17 first performs the distance measuring operation by the signal of the logic control circuit 16, and the signal is sent to the object distance detecting circuit 14. It is sent, digitized, and sent to the zoom ring rotation calculation circuit 13. Further, 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 calculation circuit 13 as the output of the zooming signal processing circuit 15. The arithmetic circuit 13 performs the arithmetic operations shown in Table 1 according to the outputs of the circuits 14 and 15. For example, when the subject distance is 4 m and the switching position of the zooming operation means 16 is f = 50 mm, the number of both is combined and the number of 41 is stored as shown in Table 1, and this is used as the reference value of the comparator 12a. To do.

The motor control circuit 11 rotates the motor 8 in the normal direction in response to a signal from the logic control circuit 16 to rotate the zoom ring 6 from WIDE to the TELE direction. The rotation of the zoom ring 6 is controlled by the pulse plate 9
Is pulsed and output by the pulse detection circuit 10, detected by the pulse detection circuit 10 and added to the comparator 12. At this time, up to 10 pulses are emitted when the lens units 1 and 3 extend the lens from the retracted position to the position shown in FIG.

Position signals are successively issued by the forward rotation of the motor 8, and when the number of pulses reaches 41, the comparator 12a is inverted and an end signal is issued, and the motor control circuit 11 short-circuits both ends of the motor 8. An electric brake is applied to the motor 8 to stop it.

According to FIG. 2, the amount of rotation of the zoom ring 6 at this time is about 260 °. After that, 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 in response 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 it is in the state before pressing the release button again.

In the above embodiment, 7 points were switched between 35 mm and 70 mm, but the same operation can be performed by increasing or decreasing the number of points.

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. However, 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. In this way, the pulse plate 9,
The pulse detection circuit 10 and the comparator 12a are unnecessary,
The output of the arithmetic circuit 13 may be directly input to the motor control circuit 11.

(Correspondence between Invention and Embodiment) In the above embodiments, the convex lens unit 1 and the concave lens unit 3 are the lens unit of the present invention, the motor 8 is the driving means of the present invention, and the zooming operation member 18 is the present invention. The zooming magnification change instruction means corresponds to the zooming signal processing circuit 15, the zoom ring rotation calculation circuit 13, the comparator 12a, the pulse plate 9 and the pulse detection circuit 10, which correspond to the control means of the present invention.

[0045]

As described above, according to the present invention, it is possible to provide a variable power lens control device capable of reducing the load required for manufacturing and reducing the cost.

[Brief description of 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 diagram showing the movement of a taking 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.

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.

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

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

[Explanation of symbols]

 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 Arithmetic Circuit 14 Subject Distance Detection Circuit 15 Zooming Signal Processing Circuit 16 Control Circuit 17 Distance measuring module 18 Zooming operation member 19 Finder lens moving mechanism

Claims (1)

[Claims] 1. A lens unit, drive means for driving the lens unit, zoom magnification change instruction means for instructing continuous change of zoom magnification, and the drive means for driving the lens unit, A variable power lens control device comprising: a control unit that stops the lens unit stepwise in response to a continuous zoom magnification change instruction from the zoom magnification change instruction unit.