JPH1138306A - Driving device and optical equipment - Google Patents

Abstract

(57) [Problem] To smoothly and electrically drive a driven member in accordance with the operation speed of a manual operation member. A change direction and a change amount of a manual operation member are detected from a motor for driving a driven body and two pulse trains generated with a phase shift due to operation of the manual operation member. In the driving device to be controlled,
A first detection mode for detecting a change amount of one pulse train with a coarse resolution, a second detection mode for detecting a change amount of the pulse train with a fine resolution, and a case where the pulse change amount within a predetermined time is larger than a predetermined value. Selecting means for selecting the first detection mode and selecting the second detection mode when the detection mode is smaller.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a driving device and an optical apparatus for electrically driving a driven member by operating a manual operation member.

[0002]

2. Description of the Related Art Conventionally, an interchangeable lens system used for a video device such as a video camera will be described with reference to FIG. In the conventional zoomable lens unit, the variable power lens 802 and the correction lens 803 are mechanically connected by a cam, and when the variable power operation is performed manually or electrically, the variable power lens 802 and the correction lens 803 are integrated. Move. These zoom lens 802 and correction lens 803 are collectively called a zoom lens.

In such a lens system, the front lens 80
Reference numeral 1 denotes a focusing lens, which performs focusing by moving in the optical axis direction. Light that has passed through these lens groups is imaged on the imaging surface of the imaging element 804, photoelectrically converted into an electric signal, and output as a video signal. This video signal is sampled and held by the CDS / AGC 805, amplified to a predetermined level by the A / D converter 806, converted into digital video data, input to the process circuit of the camera, and converted into a standard television signal. Is converted and the band-pass filter 807 (hereinafter referred to as BP
F).

A BPF 807 extracts a high frequency component in a video signal, extracts only a signal corresponding to a portion set in a focus detection area in a screen by a gate circuit 808, and an integer multiple of a vertical synchronizing signal by a peak hold circuit 809. The peak hold is performed at intervals synchronized with the above, and an AF evaluation value is generated. The AF evaluation value is taken into the main body AF microcomputer 810, and a focusing speed corresponding to the degree of focusing and a motor driving direction are determined so as to increase the AF evaluation value in the main body AF microcomputer 810, and the speed and direction of the focus motor are determined. Is sent to the lens microcomputer 811. Lens microcomputer 811
Performs focus adjustment by moving the focusing lens 801 in the optical axis direction by a motor 813 via a motor driver 812 as instructed by the main body microcomputer 810.

Further, the above-mentioned AF function is invalidated,
When performing the focusing operation with the sense of the photographer himself (manual focusing), the microcomputer 810 determines the driving direction and driving speed of the focus lens 801 according to the operation state of the focus switch 819, and The data is sent to a focus motor driver 812, and the focus lens 801 is driven via the focus motor 813 to obtain a focusing effect.

The microcomputer 810 controls the zoom lenses 802 and 803 in accordance with the operation state of the zoom switch 818.
Of the lens unit 816 is determined.
And drives the zoom lenses 802 and 803 via the zoom motor 815,
Get a zooming effect. In the camera body 817, the lens unit 816 can be separated, and by connecting another lens unit, the shooting range is expanded.

In a general lens system of a front focus type, a focus lens and a zoom lens are mechanically connected to an operation ring fitted to a lens barrel, and each lens is moved by rotating the operation ring. It is possible to make it. Thus, the photographer can smoothly operate the zoom operation and the focusing operation.

On the other hand, in a consumer integrated camera, in order to make it possible to reduce the size and photograph the front of the lens, mechanically connecting the correction lens and the variable power lens with a cam is stopped, and the movement trajectory of the correction lens is determined in advance. An inner focus type lens that stores lens cam data in a microcomputer, drives a correction lens according to the lens cam data, and adjusts the focus with the correction lens is becoming mainstream, inexpensive, and simplified system This has the advantage of reducing the size and weight of the lens barrel.

FIG. 7 shows a simple configuration of a conventionally used inner focus type lens system. In FIG. 7, reference numeral 901 denotes a fixed first lens group; 902, a second lens group for performing zooming; 903, an aperture; 904, a fixed third lens group;
Compensates for the movement of the focal plane due to the focus adjustment function and zooming,
A fourth lens group (hereinafter, referred to as a focus lens) 906 having a so-called competition function is an imaging surface.

As is well known, in the lens system configured as shown in FIG. 7, the fourth lens group 905 has both a competing function and a focus adjusting function. Fourth lens group 9 for focusing
The position 05 differs depending on the subject distance. When the subject distance is changed at each focal length, the position of the fourth lens group 905 for focusing on the imaging surface is plotted continuously as shown in FIG. During zooming,
If the locus shown in FIG. 8 is selected according to the subject distance, and the fourth lens group 905 is moved along the locus, zooming without blurring becomes possible.

In a front lens type lens system, a compensating lens independent of the variable power lens is provided, and the variable power lens and the compensating lens are connected by a mechanical cam ring. Therefore, for example, if a knob for manual zoom is provided on this cam ring and the focal length is manually changed, no matter how fast the knob is moved,
The cam ring rotates following this, and the variable power lens and the compensating lens move along the cam groove of the cam ring. Therefore, if the focus lens is in focus, the above operation does not cause blur.

On the other hand, in the control of the inner focus type lens system, a plurality of trajectory information shown in FIG. 8 is stored in some form (the trajectory itself or a function using the lens position as a variable). In general, a locus is selected according to the positions of a focus lens and a variable power lens, and zooming is performed while following the selected locus.

Further, in order to read out the position of the focus lens with respect to the position of the variable power lens from the storage element and apply it to lens control, the position of each lens must be read out with a certain degree of accuracy. In particular, as is apparent from FIG. 8, when the variable power lens moves at a constant speed or a speed close thereto, the inclination of the locus of the focus lens changes every moment due to a change in the focal length. This indicates that the moving speed and the moving direction of the focus lens change every moment, in other words, the actuator of the focus lens must perform an accurate speed response from 1 Hz to several hundred Hz. Become.

It is becoming common to use a stepping motor for the focus lens group of the inner focus lens system as an actuator satisfying the above requirements. The stepping motor rotates in perfect synchronization with the stepping pulse output from the microcomputer for lens control and the like, and the stepping angle per pulse is constant, so that high speed response, stopping accuracy and position accuracy are obtained. It is possible. Furthermore, when a stepping motor is used, since the rotation angle with respect to the number of stepping pulses is constant, the stepping pulse can be used as it is as an incremental encoder, and there is an advantage that no special position encoder needs to be added. .

As described above, in the case where the zooming operation is to be performed while keeping the focus by using the stepping motor, the trajectory information shown in FIG. It is necessary to read locus information according to the position or moving speed of the variable power lens, and move the focus lens based on the information.

FIG. 9 is a diagram for explaining an example of a proposed trajectory following method. In FIG. 9, Z0,
Z1, Z2,. . . Z6 indicates the position of the variable power lens, and a0, a1, a2,. . . a6 and b0, b1, b
2. . . b6 is a representative trajectory stored in the microcomputer. Also, p0, p1, p2,. . . p6 is a trajectory calculated based on the two trajectories. The calculation formula of this locus is described below.

P (n + 1) = | p (n) −a (n) | / | b (n) −a (n) | × | b (n + 1) −a (n + 1) | + a (n + 1) ‥‥ ( 1) According to equation (1), for example, in FIG. 9, when the focus lens is at p0, the ratio of p0 internally dividing line segment b0-a0 is determined, and line segment b1-a1 is internally divided according to this ratio. The point is denoted by p1. From the position difference of p1-p0 and the time required for the variable power lens to move from Z0 to Z1,
The moving speed of the focus lens for keeping the focus is known.

Next, a description will be given of a case where the stop position of the variable power lens is not limited only on the boundary possessing the stored representative trajectory data. FIG. 10 is a diagram for explaining an interpolation method in the direction of the position of the variable power lens. A part of FIG. 9 is extracted, and the variable power lens is optional.
In FIG. 10, the ordinate and the abscissa indicate the focus lens position and the variable power lens position, respectively. The representative trajectory position (focus lens position with respect to the variable power lens position) stored in the lens control microcomputer is represented by the variable power lens. Position Z0, Z
1, ‥‥ Zk-1, Zk. . . Zn The focus lens position at that time is divided into a0, a1,. . . ak-1, ak. . . an b0, b1,. . . bk-1, bk. . . bn.

Now, when the zoom lens position is at Zx which is not on the zoom boundary and the focus lens position is Px,
When ax and bx are obtained, ax = ak− (Zk−Zx) × (ak−ak−1) / (Zk−Zk−1) ‥‥ (2) bx = bk− (Zk−Zx) × (bk −b k−1) / (Zk−Zk−1) ‥‥ (3)

That is, the current zoom lens position and two zoom boundary positions sandwiching the current zoom lens position (eg, Zk and Zk-1 in FIG. 10).
According to the internal division ratio obtained from the above, four stored representative locus data (ak, ak-1, bk, bk-
Ax and bx can be obtained by dividing the object having the same object distance in 1) by the internal division ratio. And a
According to the internal division ratio obtained from x, Px, and bx, four stored representative data (ak, ak-1, b in FIG. 10)
k, bk-1), those having the same focal length are internally divided by the internal division ratio as in equation (1) to obtain pk, pk-1
Can be requested. At the time of zooming from wide to tele, the focus lens for maintaining focus is determined from the position difference between the following focus position pk and the current focus position px and the time required for the variable magnification lens to move from Zx to Zk. You can see the moving speed.

In zooming from telephoto to wide, focusing is performed based on the position difference between the following focus position pk-1 and the current focus position Px and the time required for the variable magnification lens to move from Zx to Zk-1. The moving speed of the focus lens for keeping the distance is known. A trajectory following method as described above has been proposed.

As described above, in the inner focus type lens, a stepping motor is combined as an actuator to reduce the size and simplify the drive transmission system. Since the stepping pulse supplied to the stepping motor can be easily generated in the lens control microcomputer, the lens position detection is performed by counting the number of stepping pulses output by the lens control microcomputer itself. It is possible to accurately know the position of the lens without providing a special encoder or the like.

By the way, in the above-mentioned general lens system of the front lens focus type, "a focus lens and a zoom lens are mechanically connected to an operation ring fitted to a lens barrel,
In the “mechanism that moves each lens by rotating the operation ring”, the lens moves in proportion to the amount of rotation.

Therefore, the zooming can be smoothly performed from the coarse adjustment to the fine adjustment.

It is excellent in such points.

However, in the lens system of the inner focus type, all the movable lenses are arranged in the lens barrel.

If the lens is rotated by a mechanically connected cam ring or the like without using a control circuit, an error occurs between the count value of the drive pulse of the stepping motor and the actual lens position.

The drive transmission system having a simple structure is not suitable for mechanical manual operation.

For these reasons, it is difficult to mechanically couple the operation ring and the lens and move the lens by an external force, and it is difficult to realize manual operability of the front lens type lens.

In particular, in the interchangeable lens system described with reference to FIG. 6, depending on the lens to be mounted, the camera is held by holding the lens barrel, and if there is no zoom operation member on the lens side, the angle of view can be adjusted. For this reason, it is necessary to temporarily look away from the viewfinder and search for the zoom operation switch on the main body side, which causes problems such as camera shake and hinders smooth shooting.

On the other hand, there has been proposed a method of moving a zoom lens and a focus lens by fitting an encoder to a lens barrel and electrically detecting a rotation direction and a rotation speed of the encoder. here,
An operation ring that is not mechanically connected to each lens,
Hereinafter, the configuration and the detection method will be described in detail with reference to FIG.

In FIG. 11A, reference numeral 1301 denotes a rotary encoder fitted to a lens barrel; 1302, a comb-tooth portion of an encoder having a light-reflecting portion and a light-transmitting portion; 1303 and 1304; A first sensor and a second sensor, each of which includes a light emitting and receiving element having a light emitting unit 1306 and a light receiving unit 1307.

The state of the output signal changes depending on whether or not the reflected light from the comb tooth 1302 is received. Here, FIG. 11B is an enlarged view of a portion 1305 surrounded by a broken line in FIG.

When the encoder 1301 is rotated, the output signals of the first sensor 1303 and the second sensor 1304 change as shown in FIGS. The positional relationship between the first sensor 1303 and the second sensor 1304 is determined so that the phases of the two output signals are shifted by an appropriate amount.

Next, a method of detecting the operation direction and the operation amount from the output signal of the manual ring will be described. First, as one of the detection methods, a method (first detection method) of detecting one rising edge or falling edge of the output signal, detecting the state of the other output signal, and detecting the operation direction and the operation amount will be described.

FIGS. 11C and 11D show the first sensor 1303.
The output phase relationship between the first sensor 1303 and the second sensor 1304 when the operation ring encoder 1301 is operated in the positive direction and the negative direction with reference to the output signal of FIG.

When the operation ring encoder 1301 is operated in the forward direction, the output signal of the second sensor 1304 becomes L level when the output signal of the first sensor 1303 rises,
At the time of falling, the output signal of the second sensor 1304 becomes H level.

On the other hand, when the operation ring encoder 1301 is operated in the negative direction, the output signal of the second sensor 1304 becomes H level when the output signal of the first sensor 1303 rises, and the output signal of the second sensor 1304 when falling. The signal goes to L level.

That is, the operation direction of the operation ring encoder 1301 can be detected by determining the output signal level of the second sensor 1304 when the output signal of the first sensor 1303 rises and falls. Also,
At the time of rising and falling of the first sensor 1303, the operation amount of the operation ring encoder 1301 is detected by continuously setting the counter (not shown) to +1 when operating in the positive direction and −1 when operating in the negative direction. Can be. With this detection method, the operation direction and the operation amount can be detected with half the resolution of the comb-tooth portion 1302.

As a method of further reducing the detection resolution, the above-described detection method detects the rising and falling edges of one output signal to detect the operation direction and the operation amount, whereas the rising and falling edges of both output signals are detected. Is detected (the rising or falling of one pulse of the second sensor 1304 is located between one pulse of the first sensor 1303, and if this period is defined as one pulse, the resolution is reduced to 1/4 as described later). There is a method of detecting the operation direction and the operation amount (second detection method). Thus, the comb teeth 13
The operation direction and the operation amount can be detected with a resolution of 1/4 of 02.

As described above, the operation direction and the operation amount of the operation ring are detected, and the detection results are applied to the movement direction and the movement amount (or the movement speed) of the lens. As a result, FIG.
Equipped with an encoder like this, driving a lens actuator such as a stepping motor according to the rotation of the ring, while maintaining the same operational feeling as the front lens type, while being an inner focus type lens system, The lens operation can be performed.

[0042]

The phase difference between the output signals of the aforementioned manual ring is ideally 90 deg.
However, the phase difference varies depending on the distance between the two light emitting and receiving elements, the processing accuracy of the teeth of the comb teeth, and the like. This variation increases as the teeth of the comb teeth become finer.

Therefore, the fineness of the teeth of the comb-tooth portion that is set to reliably obtain an appropriate signal phase difference is inevitably determined.
The cycle of the output signal of the manual ring having the comb teeth set as described above is coarse with respect to the operation amount of the ring. For this reason, if the manual ring is operated slowly, there may be a case where the detection ring or less is erroneously determined not to be operated even if the operation of the operation ring is performed. At this time, the lens repeatedly moves and stops at the changing cycle of the encoder output, and the lens becomes unnatural on the shooting screen.

Depending on the photographing situation, the photographer may want to quickly operate the lens. At this time, the photographer operates the manual ring quickly, and the change in the encoder output becomes faster. The detecting means detects the operation direction and the operation amount for each change in the output of the encoder. If the change in the output of the encoder is earlier than the above-described detection processing time, it cannot be accurately detected.

As a result, the lens operates slowly even if the operation ring is operated quickly, or moves in the direction opposite to the operation direction. In addition, processing time, such as other autofocus processing, auto iris processing, zooming processing, and motor driving processing, is disturbed.

An object of a first invention according to the present application is to solve the above-mentioned problems and to provide a drive device capable of smoothly and electrically driven a driven member in accordance with the operation speed of a manual operation member. .

An object of the second invention according to the present application is to reduce the unnaturalness of an optical element such as a lens on a photographing screen when the manual operation member is slowly operated, and to quickly operate the manual operation member. In such a case, an object of the present invention is to provide an optical device capable of accurately detecting an encoder output change while reducing the processing time of a microcomputer or the like.

[0048]

According to a first aspect of the present invention, a motor for driving a driven body and at least two motors whose phases are shifted by a manual operation member are provided. A pulse train generating means for generating a pulse train, a pulse change direction from an output pulse of the pulse train generating means,
In a driving device having a pulse train detecting means for detecting a pulse change amount, and a control means for controlling the motor based on an output of the pulse train detecting means, the control means may determine a change amount of the pulse train from the pulse train detecting means with a coarse resolution. A first detection mode for detecting the change amount of the pulse train with a fine resolution, and a first detection mode when the pulse change amount within a predetermined time is larger than a predetermined value. And selecting means for selecting the second detection mode when it is small.

In a second configuration for realizing the object of the first invention according to the present application, the first detection mode detects a pulse change direction and a pulse change amount at a rising and falling timing of one of the pulse trains. In the second detection mode, the pulse change direction and the pulse change amount are detected at the rising and falling timings of a plurality of pulse trains.

A first configuration for realizing the object of the second invention according to the present application has the above-described driving device, and drives the optical member as the driven body.

In a second configuration for realizing the object of the second invention according to the present application, the optical member as the driven body is a lens movable in the optical axis direction.

In a third configuration for realizing the object of the second invention according to the present application, the lens is detachable from the image pickup apparatus main body.

[0053]

BEST MODE FOR CARRYING OUT THE INVENTION

(First Embodiment) FIGS. 1 to 5 show a first embodiment of the present invention.

In this embodiment, the present invention is applied to driving of a zoom lens of an interchangeable lens system, and FIG. 1 shows the configuration of this embodiment. Light from a subject is fixed to a first lens group 101, a second lens group 102 for changing magnification (hereinafter, referred to as a zoom lens), an aperture 103, a fixed third lens group 104, and a focal point. After passing through a fourth lens group 105 (hereinafter referred to as a focus lens) having both an adjustment function and a competition function for correcting the movement of the focal plane due to zooming, a red component of the three primary colors is converted into an image sensor 106 such as a CCD. Above, a green component is formed on an image sensor 107 such as a CCD, and a blue component is formed on an image sensor 108 such as a CCD.

The zoom ring 1301 and the first sensor 130 corresponding to the conventional encoder shown in FIG.
3 and 2nd sensor 1304 are shown. Each image formed on the image sensor 106, 107, 108 for each color component after passing through the lens is subjected to photoelectric conversion, and is converted into amplifiers 108, 10
At 9 and 110, the signals are amplified to the optimum levels and input to the camera signal processing circuit 112, converted to standard television signals, and simultaneously input to the AF signal processing circuit 113. The AF evaluation value generated by the AF signal processing circuit 113 is read by a data reading program 115 in the main microcomputer 114 and transferred to the lens microcomputer 116.

Further, the main body microcomputer 114 reads the zoom switch 130 and the AF switch 131, and sends the switch state to the lens microcomputer 116. In the lens microcomputer 116, the AF switch 131 is turned off and the zoom ring encoder 130
When the camera 1 is rotating or the zoom switch 130 is pressed, the computer zoom program 119 drives in the tele or wide direction depending on the rotation direction of the zoom ring 1301 or the direction in which the zoom switch 130 is pressed. By transmitting a signal to the zoom motor driver 122 based on the lens cam data 120 stored in advance in the lens microcomputer, the variable magnification lens 102 is driven via the zoom motor 121 and a signal is transmitted to the focus motor driver 126 at the same time. Focus motor 1
The zooming operation is performed by moving the focus competition lens 105 through 25.

When the AF switch 131 is on and the zoom ring encoder 1301 is rotating or the zoom switch 130 is pressed, it is necessary to keep the in-focus state.
However, referring to not only the lens cam data 120 stored in advance in the lens microcomputer but also the AF evaluation value signal sent from the main body microcomputer, the zoom operation is performed while maintaining the position where the AF evaluation value becomes maximum.

When the zoom ring encoder 1301 is rotating and the zoom switch 130 is pressed, the operability similar to that of the front lens is realized by giving priority to the zoom ring encoder 1301. Also, when the AF switch 131 is on and the zoom ring encoder 1301 is not rotating or the zoom switch 130 is not pressed, the AF program 117 focuses the image so that the AF evaluation value signal sent from the main body microcomputer becomes maximum. A signal is sent to the motor driver 126 to move the focus compensation lens 105 via the focus motor, thereby performing an automatic focus adjustment operation.

Next, when the speed of the zoom ring operation is fast, the operation amount is detected by a coarse resolution detection method, and when the zoom ring operation speed is low, the operation amount is detected by a fine resolution detection method. A method for smoothly and accurately performing a manual lens operation with respect to a ring operation will be described.

First, a first detection method for detecting the operation of the zoom ring 1301 with a coarse resolution will be described with reference to FIG.
FIG. 2 is a flowchart of the first detection method. The processing in FIG. 2 is an interrupt processing routine in the microcomputer for counting the rotation direction and the amount of rotation of the zoom ring in the lens microcomputer.

The triggering factor of the interrupt is the switching point of the output waveform voltage of the first sensor 1303 of the ring rotation detection encoder, and the rising edge of the output of the first sensor 1303 shown in FIGS. When the falling edge is detected, an interrupt occurs, and the processing in FIG. 2 is executed.

The interrupt processing of 201 is started, and a “rotation flag” is set at 202. The “rotation flag” is a flag indicating that the zoom ring has rotated. After the process 202, it is determined at 203 whether the detection method is the first detection method (1) or the second detection method (0).

The "detection method flag" is a flag indicating whether the detection method is the first detection method (1) or the second detection method (0).
It is determined in a process synchronized with a vertical synchronization signal shown in FIG. If the current “detection method flag” is 203, the first detection processing after 204 is performed. If the current “detection method flag” is 0 in 203, the second detection processing after 301 shown in FIG. Do.

At 204, the current interrupt is the first encoder.
It is determined whether the output is the rising edge or the falling edge of the output of the sensor 1303. If the output is the rising edge, it is determined at 205 whether the output signal of the second sensor 1304 is Low. If the output signal is negative, the combination of the two outputs is as shown in FIG. In the case of c), a ring flag indicating that the rotation direction of the zoom ring is the forward rotation direction is set in 206, the zoom ring counter ZC indicating the amount of rotation of the zoom ring is incremented by 2, and the process proceeds to 209.

The zoom ring counter is reset after power is turned on, and counts in the first detection processing and the second detection processing to manage the amount of rotation of the zoom ring.

The detection resolution of the first detection method is twice the detection resolution of the second detection method.

At 205, the output of the second sensor 1304 becomes Hi.
Then, since the combination of the two outputs is the case shown in FIG. 11D, the rotation flag of the zoom ring is determined to be the reverse rotation direction in 207, the ring flag is cleared, the zoom ring counter ZC is decremented by 2, and the process proceeds to 209. .

If the output of the first sensor 1303 is a falling edge in step 204, the second sensor 1304 is entered in 208.
Is determined, and if Low, go to 207; if Hi, 2
In step 06, the ring flag is set, the zoom ring counter is counted, and the flow advances to step 209.

The processing after 209 is processing for canceling the mismatch of the zoom ring counter value due to the difference in the detection method when the detection method is switched, and is synchronized with the vertical synchronization signal shown in FIG. This is performed when the “detection method switching flag” set in the processing is “1”.

If the “detection method switching flag” is 1 in 209, the process proceeds to 210, and in the previous detection processing, the detection processing is performed by interruption of a change in the encoder output of one of the first sensor 1303 and the second sensor 1304. Reference is made to an “interrupt encoder flag” indicating whether or not the operation has been performed.

"Interrupt encoder flag" = 0 (first
In the case where the detection process is performed by interruption of the output change of the sensor 1303), the current ring rotation direction is compared with the previous ring rotation direction at 211. In the case of the different direction, the "ring flag" is referred to at 212, and if "ring flag" = 1, the zoom ring counter is decremented by 1 at 213 and the "detection switching flag" is cleared at 215.
In step 6, the "ring flag" is stored in the "ring flag 1", and the detection process is terminated.

If "ring flag" = 0 at 212,
At 214, the zoom ring counter is incremented by one,
Processing after step 215 is performed, and the detection processing ends.

In the case of the same direction at 211, the processing after 215 is performed, and the detection processing ends.

If the “interrupt encoder flag” = 1 in 210 (the detection processing was performed by interruption of the output change of the second sensor 1304), the current ring rotation direction is compared with the previous ring rotation direction in 217. In the case of the same direction, the processing after step 212 is performed, and the detection processing ends.
If the direction is different in 217, the processing after 215 is performed, and the detection processing ends. If the "detection method switching flag" is 0 in 209, the processing in 216 is performed, and the detection processing ends.

Next, a second detection method for detecting the operation of the zoom ring 1301 with a fine resolution will be described with reference to FIG. FIG. 3 is a flowchart of the second detection method. The processing in FIG. 3 is the same as the processing in FIG. 2 and is an interruption processing routine in the microcomputer for counting the rotation direction and the rotation amount of the zoom ring in the lens microcomputer. The activation factor of the interrupt is the ring rotation detection first sensor 1303 and the second sensor 13.
4 is a switching point of the output waveform voltage of FIG.
First sensor 1 shown in (a), (b), (c), (d)
When the rising edge and the falling edge of the output of the sensor 303 and the output of the second sensor 1304 are detected, an interrupt occurs, and the processing of FIG. 3 is executed.

FIGS. 4A and 4B show the first sensor 1303.
4C shows the output phase relationship of the first sensor 1303 and the second sensor 1304 when the operation ring encoder 1301 is operated in the positive direction and the negative direction based on the output signal of FIG.
(D) shows the output phase relationship of the first sensor 1303 and the second sensor 1304 when the operation ring encoder 1301 is operated in the positive direction and the negative direction with reference to the output signal of the second sensor 1304.

As described above, if the "detection method flag" is 0 in 203, the second detection processing after 301 shown in FIG. 3 is performed.

At 301, the process is started. At 302, it is determined whether the current interruption is an interruption of the output change of the first sensor 1303 or an interruption of the output change of the second sensor 1304. At 302, the current interrupt is the first sensor 1303.
In step 303, the "interrupt encoder flag" is cleared. The “interrupt encoder flag” is the first sensor 1303, the second sensor 1304
This flag indicates which output change has caused the interruption, and is used to match the zoom ring counter ZC when the detection processing method is switched.

Next, at 304, it is determined whether the current interrupt is the rising edge or the falling edge of the output of the first sensor 1303, and if it is the rising, at 305, it is determined whether the output signal of the second sensor 1304 is Low. Determine. If 305 is negative, the combination of the two outputs is the case of FIG. 4A, so the ring flag is set at 306, and the zoom ring counter ZC is incremented by one.

At 305, the output of the second sensor 1304 becomes Hi.
If so, since the combination of the two outputs is the case of FIG. 4B, the ring flag is cleared at 307 assuming that the rotation direction of the zoom ring is the reverse rotation direction, and the zoom ring counter ZC is decremented by one.

If the output of the first sensor 1303 is a falling edge in step 304, the output signal of the second sensor 1304 is determined in step 308.
If Hi, the process proceeds to step 306, where a ring flag is set, and the zoom ring counter is counted.

At 302, the current interrupt is sent to the second sensor 13
If the interrupt is an output change interrupt of 04, an "interrupt encoder flag" is set at 309. Next, at 310, it is determined whether the current interrupt is a rising edge or a falling edge of the output of the second sensor 1304. If it is a rising edge, at 311 it is determined whether the output signal of the first sensor 1303 is Hi.

If 311 is negative, the combination of the two outputs is shown in FIG.
In the case of (c), a ring flag is set in 306, and the zoom ring counter ZC is incremented by one. If the output of the first sensor 1303 is low at 311, the combination of the two outputs is the case of FIG. 4D, and the ring flag is cleared at 307 assuming that the rotation direction of the zoom ring is the reverse rotation direction, The zoom ring counter ZC is decremented by one. If the output of the second sensor 1304 is a falling edge in the process 310, 3
12, the output signal of the first sensor 1303 is determined, and Hi is determined.
If it is low, the process proceeds to 307, and if it is low, the process proceeds to 306, a ring flag is set, and the zoom ring counter is counted.

The processing after step 313 is processing for canceling the mismatch of the zoom ring counter value due to the difference in the detection method when the detection method is switched. 313
When the “detection method switching flag” is 1 in 3
14 and the first sensor 13 in the current detection process.
03, an “interrupt encoder flag” indicating which of the encoders 1304 interrupted the encoder output change and performed the detection process.

"Interrupt encoder flag" = 0 (first
In the case of (the detection process is performed by interruption of the output change of the sensor 1303), the “detection method switching flag” is cleared in 315, and the process proceeds to 304 to perform the zoom ring counter process again. In the process 313, the "detection method switching flag"
Is “0”, and if “interrupt encoder flag” = 1 in processing 314 (detection processing was performed by interruption of the output change of the second sensor 1304), the “detection method switching flag” is cleared in 316. The detection processing ends.

FIG. 5 is a flowchart showing the operation of detecting the operation of the zoom ring 1301 by selecting the first detection method and the second detection method according to the operation speed, and the zoom operation performed based on the detection result of the zoom ring. It will be described using FIG. This processing is performed in synchronization with the vertical synchronization signal (V cycle).

The processing is started at 501, and mutual communication with the microcomputer of the main body is performed at 502. As described above, the main unit microcomputer sends the zoom 130 and AF ON / OF on the camera body side.
Information such as F key information and AF evaluation value is sent. Processing 5
At 03, it is determined whether or not the “rotation flag” is set in order to give priority to the zoom ring operation on the lens unit side. At 504, “rotation flag 1” indicating whether or not the zoom ring operation was performed in the previous main processing is performed. Is determined to be a set, and when the “rotation flag” = 0 and the “rotation flag 1” = 0 and no ring operation has been performed, the operation state of the zoom key 130 obtained through communication is determined, and according to the operation state While moving the zoom lens, the focus lens is operated in accordance with the cam locus tracing method described in the related art (517, 518, 519, 520, 5).
21) The process is terminated at 522.

If the AF is ON at the time of the zoom operation, the zoom operation is executed while performing the focus correction with reference to the AF evaluation value as described above. If the rotation flag is set in the process 503, the zoom ring rotation direction is referred to in 505.

If "ring flag" = 1 in 505, 5
In step 06, the maximum zoom lens movement speed Zsp is calculated.
Proceed to 7 to drive the zoom lens in the wide direction.

At 506, the maximum zoom lens movement speed Zs
p is obtained by taking the difference between the zoom ring counter ZC and the zoom ring counter ZC1 one cycle before the current cycle, dividing it by the time of the V cycle, and multiplying p by a predetermined coefficient α.

If "ring flag" = 0 at 505, 5
08, the maximum zoom lens movement speed Zsp is calculated, and 50
Proceed to 9 to drive the zoom lens in the telephoto direction. At 508, the maximum zoom lens movement speed Zsp is set to the zoom ring counter ZC1 and the zoom ring counter ZC one cycle before.
Is obtained, divided by the time of the V cycle, and multiplied by a predetermined coefficient α. At 504, “rotation flag 1” = 1
If the ring operation has been performed in step 510, the process proceeds to step 510, where the zoom lens is stopped, and Zsp = 0 is set.

Next, in step 511, the maximum zoom lens movement speed Zsp calculated as described above is regarded as the zoom ring rotation speed, and is compared with a predetermined value B.
The detection method is selected, and “detection method flag” = 1.

If Zsp <B in 511, the second detection method is selected, and the "detection method flag" is set to "0". The magnitude of the predetermined value B is set to a value that makes the detection processing time of the second detection method longer than the output change of the encoder due to the operation of the zoom ring.

In step 514, in order to perform processing for canceling inconsistency in the zoom ring counter value due to a difference in the detection method when the above-described detection method is switched, the “detection method flag” selected this time and the previously selected detection method flag are used. The detected “detection method flag 1” is compared.
The "rotation flag", "detection method flag", and "zoom counter" are stored in "rotation flag 1,""detection method flag 1," and "zoom counter 1," respectively. finish.

At step 514, the “detection method flag” selected this time
If the "detection method flag 1" selected previously is different from the "detection method flag 1", the "detection method switching flag" is set, the flow shifts to 515, and the process ends.

Although the present embodiment has been described by taking an interchangeable lens system as an example, an imaging device in which a lens unit and a camera unit are integrated may be used.

In the present embodiment, the manual drive of the zoom lens has been described as an example. However, the present invention may be applied to the manual drive of a focus lens.

[0098]

According to the first to fifth aspects of the present invention, the driven member is smoothly driven in accordance with the operation speed even if the manual operation member such as the manual ring is operated slowly or quickly. be able to.

If the present invention is applied to a camera or the like, it is possible to reduce unnaturalness on a photographing screen caused when a manual operation member such as a manual ring is slowly operated, and to reduce a microcomputer when a manual ring is operated quickly. And the output change of the pulse train generating means can be accurately detected while reducing the processing time of the above.

[Brief description of the drawings]

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

FIG. 2 is a first detection method (mode) according to the first embodiment;
5 is a flowchart showing the process.

FIG. 3 is a second detection method (mode) according to the first embodiment;
5 is a flowchart showing the process.

FIGS. 4A to 4D are diagrams illustrating output phase relationships of first and second sensors according to the first embodiment.

FIG. 5 is a flowchart of a zoom operation performed based on a detection result of a zoom ring according to the first embodiment.

FIG. 6 is a diagram of an interchangeable lens system used for a conventional video device such as a video camera.

FIG. 7 is a configuration diagram of a conventional inner focus type lens system.

FIG. 8 is a trajectory information diagram of the inner focus lens.

FIG. 9 is a diagram illustrating an example of a trajectory tracking method.

FIG. 10 is a diagram for explaining an interpolation method in the position direction of the variable power lens.

11A is a perspective view showing a configuration of a manual ring, FIG. 11B is a perspective view of a sensor, and FIGS. 11C and 11D are first and second views.
FIG. 4 is a diagram showing an output phase relationship of the sensor of FIG.

[Explanation of symbols]

 1301 Zoom ring 1303, 1304 Sensor 102 Zoom lens 105 Focus lens 125 Motor 126 Lens microcomputer

Claims (5)

[Claims] 1. A motor for driving a driven body, a pulse train generating means for generating at least two pulse trains out of phase by operating a manual operating member, and a pulse change direction and a pulse change from an output pulse of the pulse train generating means. A drive unit having a pulse train detecting means for detecting an amount and a control means for controlling the motor by an output of the pulse train detecting means, wherein the control means detects a change amount of the pulse train from the pulse train detecting means with a coarse resolution A first detection mode,
A second detection mode for detecting a change amount of the pulse train with a fine resolution; and a first detection mode when the pulse change amount within a predetermined time is larger than a predetermined value; A drive unit having a selection unit for selecting a detection mode. 2. The first detection mode detects a pulse change direction and a pulse change amount at a rising and falling timing of one pulse train, and the second detection mode includes a rising and falling timing of a plurality of pulse trains. 2. The driving device according to claim 1, wherein a pulse change direction and a pulse change amount are detected. 3. An optical apparatus comprising the driving device according to claim 1 or 2, and driving an optical member as the driven body. 4. The optical apparatus according to claim 3, wherein the optical member as the driven body is a lens movable in an optical axis direction. 5. The optical apparatus according to claim 4, wherein the lens is detachable from an imaging apparatus main body.