JP2536672B2 - Drive control device for camera optical system - Google Patents

Description

Detailed Description of the Invention [Industrial applications]

 The present invention relates to a drive control device for an optical system of a camera.

[Prior art]

In an optical camera, a video camera, or the like, it is, for example, not possible to use a driving force of a motor to perform displacement of an optical system during at least one of a focusing operation and a zooming operation. It is a conventionally known matter as disclosed in Japanese Laid-Open Patent Publication No. 60-143309 and Japanese Laid-Open Patent Publication No. 63-33720. In addition, regardless of whether the camera is an optical camera or a video camera, a camera equipped with an autofocus control mechanism has been remarkably popular in recent years. At that time, it is often possible to perform a photographing (imaging) operation by a manual operation. In the above-mentioned Japanese Patent Laid-Open No. 60-143309, when zooming is performed by moving the variator lens group in the case where focus adjustment is performed by moving the front lens in a zoom lens having a four-group configuration, The deviation from the in-focus state that occurs can be easily corrected by moving the compensator lens group using a cam, but if an automatic focus adjustment mechanism is applied to the front lens, the heavy front lens must be moved during automatic focus adjustment. Since it is a problem that does not happen, it is possible to fix the front lens and move the compensator lens group to adjust the focus, as described above, move the compensator lens group to adjust the focus. If this is done, the deviation from the in-focus state caused by moving the variator lens group for zooming will be corrected again by the compensator lens group. It is necessary to adjust the focus by moving the lens, but when the automatic focus adjustment mechanism is applied, it is automatically brought into the in-focus state, and the compensator lens is used even in the photographing (imaging) operation by the manual operation described above. In order to facilitate focus adjustment by moving the lens group, the position of the compensator lens group necessary for focusing is set to the position of the variator lens group in accordance with the change in the focal length caused by the movement of the variator lens group. In addition, a means for detecting the position of the variator lens group and a means for detecting the position of the compensator lens group are provided, and the compensator is stored by the above-mentioned stored information corresponding to the detection result of the position of the variator lens group. It describes matters such as controlling the position of the lens group by driving a DC motor. Further, the camera described in Japanese Patent Laid-Open No. 60-143309 mentioned above has a problem that the structure for performing the focusing operation favorably during the manual operation becomes complicated and the cost becomes high. However, the problem is that a pulse motor (stepping motor) is used as a motor for driving the compensator lens group (focus lens group), as in the camera described in JP-A-63-33720. This can be solved if the home position (zero point) when the power is turned on is used as a reference position and the position of the compensator lens group is managed by the number of pulses used to drive the pulse motor.

[Problems to be Solved by the Invention]

However, manual operation in a conventional camera configured such that the displacement of the optical system during at least one of the focusing operation and the zooming operation is performed by using the driving force of the pulse motor. As an input device that is operated from time to time, a switch that can be turned on and off is generally used as a manual switch. However, as described above, when the photographer manually operates using a switch that can be turned on and off as a manual switch, it corresponds to the period when the manual switch is in the on state. Then, the motor drive pulse sent from the control circuit in the camera,
That is, since the motor is driven by the motor drive pulse of a constant cycle set to a cycle within the range in which the pulse motor can respond, the mode of movement of the optical system during manual operation is a constant movement speed. Therefore, it is possible to perform fine adjustment by moving the optical system in a movement mode similar to the movement mode of the optical system during actual manual operation, such as slowing down the movement speed of the optical system near the in-focus state. Have difficulty. In order to solve the above-mentioned problems, a signal generating means having a manual switch having a structure which can be used at the time of manual operation with the same usability as the adjustment of an optical system performed by the rotation of a manual ring in a normal camera, that is, A drive device for an optical system has been conceived, which is provided with a signal generating means capable of generating a signal including information on a moving direction and a moving amount of an optical system according to a rotation mode of a manual ring. However, since there are various modes of rotating the manual ring by the photographer during manual operation, for example,
When the manual ring is rapidly rotated, the motor drive pulse supplied to the pulse motor based on the signal generated by the signal generating means has a repetition frequency equal to or higher than the response frequency of the pulse motor. In such a case, there is a problem in that the movement amount of the optical system by the pulse motor does not correspond to the adjustment amount by the manual ring. Further, as is clear from the above description with the zoom lens having the four-group configuration as an example, in the optical system in which the focusing operation is performed by the rear lens, the variator lens group is used during the zooming operation. When correcting the deviation from the in-focus state caused by the movement by moving the compensator lens group, it is necessary to know the position of the variator lens group and the position of the compensator lens group, As described above, the motor drive pulse supplied to the pulse motor based on the signal generated from the signal generating means in response to the rotation of the manual ring has a repetition frequency equal to or higher than the response frequency of the pulse motor. If the movement amount of the optical system by the pulse motor and the adjustment amount by the manual ring do not correspond to each other, as described above, As a reference position for the position of the home position (zero point) at the time of ON it can not be adopted as such a simple structure to manage the number of pulses used to position the compensator lens group to the drive of the pulse motor.

[Means for Solving the Problems]

The present invention relates to a camera that is configured so that displacement of an optical system during at least one of a focusing operation and a zooming operation is performed by using a driving force by a pulse motor. The displacement control signal generating means for generating a displacement control signal including information on the moving direction and the moving amount of the optical system according to the rotation of the manual ring operated when the above-mentioned operation is performed by the above-mentioned displacement. Displacement control signals generated by the control signal generating means are integrated at predetermined constant time intervals, and when the integrated value is equal to or less than a predetermined value, the integrated value signal is output, and When the integrated value of is greater than or equal to the predetermined value, the drive signal generating means for outputting the signal of the predetermined value and the drive signal output from the drive signal generating means are used. , To provide an optical system of the drive control device for a camera which is adapted to drive the pulse motor during a certain time subsequent to a certain time of the of the drive signal is obtained.

[Action]

When the manual ring is rotated during the focusing operation or the zooming operation, the displacement control signal generating means generates a displacement control signal including information on the moving direction and the moving amount of the optical system according to the rotation of the manual ring. The displacement control signal is integrated every predetermined time. The drive pulse of the pulse motor is generated corresponding to the predetermined integrated value of the displacement control signal for each predetermined time, and the displacement control signal used to obtain the integrated value is generated. It is supplied to the pulse motor during the period following the period to which the fixed time belongs. Then, the drive pulse of the pulse motor generated corresponding to the integrated value of the displacement control signal for each of the above-mentioned constant time,
In order to prevent the pulse motor from having a repetition frequency higher than the highest frequency that can be responded to, the integrated value of the displacement control signal at each of the predetermined constant time intervals is correspondingly generated by the drive of the pulse motor. The pulse repetition frequency is limited to a value that does not exceed the maximum response frequency of the pulse motor. Thereby, for example, the position of the home position (zero point) when the power is on can be used as a reference position, and the position of the optical system can be easily managed by the number of drive pulses used to drive the pulse motor.

【Example】

Hereinafter, referring to the attached drawings, the optical system of the camera of the present invention will be described.
The specific contents of the drive control device will be described in detail.
FIG. 1 is a schematic view of a drive control device for an optical system of a camera of the present invention.
FIG. 2 is a block diagram showing the structure, and FIG. 2 is an optical system of the camera of the present invention.
3 to 8 are exploded views of a part of the drive control device of the system.
Figures for explaining the photo interrupter, FIGS. 9 to 11
The figure is a waveform diagram for explaining the operation. An embodiment of a drive control device for an optical system of a camera of the present invention
In FIG. 1 shown, 1 is a lens mount of a camera housing
Inside the lens mount 1 of this camera housing
Is provided with a lens group having a required configuration. In Fig. 1
The frame 2 shown by the dotted line in FIG.
A lens with the required configuration provided inside the und section 1
A part of the lens group moved by the lens driving unit 9 in the group.
(In the following explanation, it is said that it is a focus lens.
) Is an example. 3 is a manual ring, this manual ring
Is its rear end, as described below with reference to FIG.
A large number of a plurality of pieces are arranged at a predetermined pitch P in the circumferential direction of the annular edge portion 14 on the side.
The notches a, a ... Are formed. 4 is shown in FIG. 2 and
Two photos, as described below with reference to FIG.
Photo with interrupters 4a and 4b arranged in a predetermined arrangement
It is an interrupter structure. Manual ring 3 and photo interrupter structure
The two photo interrupters 4a and 4b in No. 4 are
The annular edge 14 on the rear end side of the dual ring 3 is shown in FIG.
And photo interrupters 4a, 4 as shown in FIG.
Assemble it so that it is located in the gap between the light emitting part and the light receiving part in b.
The manual ring 3 is shown in the
By turning in the directions of α and β of the arrow in the middle,
Two photo interrupts in the toe interrupter structure 4
Information about the rotation direction of the manual ring 3
A signal with information about the magnitude of rotation is generated, which is transmitted.
Is supplied to the signal processing unit 11. Specific structure and operation of this part
The details of the work will be described later with reference to FIG. 2 and the subsequent figures.
Have been. 5 is a photoelectric conversion element, and as this photoelectric conversion element 5,
For example, a CCD image sensor can be used. First illustrated
When the camera is a video camera, the photoelectric conversion element described above
5 uses an image sensor having a large number of pixel arrays.
Needless to say, it is used. The output signal from the photoelectric conversion element 5 described above may be output if necessary.
Output to the output terminal 12 and the automatic focus control circuit
It is supplied to (autofocus circuit) 6. Automatic focus
The point control circuit 6 corresponds to a high spatial frequency component of the subject.
Generates an autofocus control signal based on the video signal component
It comprises for example a microprocessor unit
Applied to the control circuit 7. The control circuit 7 responds to the operation mode set in the operation unit 10.
Control operation to operate each component of the camera.
Nau. That is, the operation mode set in the operation unit 10 is an example.
For example, in the case of the auto focus operation mode,
The automatic focus control signal generated by the automatic focus control circuit 6
When it is given to the control circuit 7, the control circuit 7 will
Generates a pulse motor drive signal based on the dynamic focus control signal.
And give it to the motor driver 8,
In 8, drive pulse of pulse motor is generated to drive lens
Supply it to the pulse motor of part 9 and rotate it
Then, the lens driving unit 9 → focus lens 2 → photoelectric conversion element
Child 5 → automatic focus control circuit → 6 → control circuit 7 → motor drive
Ibar 8 → lens drive unit 9 → one loop of closed loop
The automatic focus control operation is performed by the control operation of the dynamic focus control system.
Performs a control operation that can be performed. In addition, the operation mode set in the operation unit 10 is, for example, manual.
In the focus adjustment operation mode, the control circuit 7 automatically
The automatic focus control signal generated by the point control circuit 6 is the motor driver.
Control so that it is not supplied to
The rotation of the Al ring 3 causes the photo interrupter structure 4 to move.
Generated from two photo interrupters 4a, 4b in
Information about the direction of rotation of the manual ring 3 and information about the amount of rotation
Displacement generated in the signal processing unit 11 based on the signal having
When the control signal is given to the control circuit 7, the control circuit 7
Based on the displacement control signal described above, the drive signal of the pulse motor is
Signal to the motor driver 8
The driver 8 generates drive pulses for the pulse motor and
Supply to the pulse motor of the drive unit 9 and rotate it
In the manual focus mode of operation.
Rotation of Al ring 3 → Photo interrupter structure 4 → Signal
Processing unit 11 → control circuit 7 → motor driver 8 → lens drive
The open-loop manual focusing operation is performed as shown in section 9 →.
Control operation is performed. FIG. 2 is a turtle designated by reference numeral 1 in FIG.
(1) Disassemble the example structure of the lens mount part of the chassis
FIG. 2 is a diagram shown in FIG.
Illustrations of a necessary light-shielding cover and the like are omitted. In Fig. 2, reference numeral 13 denotes a front lens housed and fixed therein.
The front cover is formed on the rear end of the front cover 13.
A manual ring 3 is provided on the outer peripheral surface of the cylindrical portion 13a.
The inner peripheral surface of the is freely rotatably fitted. A circle in which the inner peripheral surface of the manual ring 3 is loosely fitted.
A lubricant such as grease may be applied to the outer peripheral surface of the cylindrical portion 13a.
It is the preferred embodiment to be applied, and
For non-slip on the outer peripheral surface of the numerical ring 3, for example on the surface
It is also desirable to stick a rubber plate on which many irregularities are formed
It is an embodiment. The annular edge on the rear end side of the manual ring 3 described above.
14 has a large number of notches a at a predetermined pitch in its circumferential direction,
a ... is configured. Has a certain pitch in the circumferential direction
On the annular edge 14 on the rear end side of the manual ring 3
Circumferential direction in the above-mentioned numerous notches a, a ...
And the length of the non-cutouts b, b ... are the same.
You. 15 is a lens barrel, and this lens barrel 15 is attached to the manual ring 3.
After penetrating inside, the cylindrical portion 13a in the front cover 13
Fit the tip of the lens barrel 15 and use the manual ring 3
The end surface 3a of the stopper 16 is fixed to the outer peripheral surface of the lens barrel 15
When the above parts are assembled in contact with the
A large number formed on the annular edge 14 on the rear end side of the ring 3.
The notches a, a ... and the non-notches b, b ... are the manual rings.
The outer circumference of the lens barrel 15 when 3 is rotated in the directions of arrows α and β
Two photo interrupters 4a and 4b fixed to the surface
Gap 27 between the light emitting part 25 and the light receiving part 26 of each
Is made ready to move across the optical path of
Teru}. In addition, the above-mentioned manual ring 3 is manually moved forward.
An arrow is drawn on the outer peripheral surface of the cylindrical portion 13a of the cover 13 and the outer peripheral surface of the lens barrel 15.
Even if it is rotated in the directions of α and β,
The lens is directly moved by the mechanical displacement of the dual ring 3.
Such as rotating the lens or moving the lens in the optical axis direction
There is no such thing as the hand of the manual ring 3 described above.
The direct action of rotating motion is the manual ring.
3. A large number of notches formed on the annular edge 14 on the rear end side
The components of a, a ... and non-cutout parts b, b ...
Of the two photo interrupters 4a and 4b in the
Gap 27 between the light emitting part 25 and the light receiving part 26 of each
Two photos that move across the optical path of
Direction of rotation of the manual ring 3 from the interrupters 4a, 4b
And output a signal containing information about the amount of rotation
is there. The photo interrupter 4a (4b) described above is the third
As illustrated in the figure, for example,
For example, a light emitting unit 25 provided with a light emitting element such as
Light-receiving part with a light-receiving element such as a photodiode
A large number of notches a, a ... And non-notches b, b ...
The circular edge on the rear end side of the manual ring 3 that is formed
Use a structure with a gap 27 that allows the part 14 to pass through.
Can be used. In carrying out the present invention, the manual ring 3
Outputs a signal containing information on the rotation direction and rotation amount.
However, other configuration modes other than the photo interrupters 4a and 4b
Of course, any of the signal generators may be used. FIG. 5A shows the photointerrupters 4a and 4b.
In the gap 27 between the light emitting part 25 and the light receiving part 26, the manual ring 3
The non-cutout portion b in the annular edge portion 14 on the rear end side is located
The light from the light emitting unit 25 does not reach the light receiving unit 26.
FIG. 5 (b) is a photo showing an example.
Between the light emitting part 25 and the light receiving part 26 in the interrupters 4a and 4b
In the gap 27, in the annular edge 14 on the rear end side of the manual ring 3.
The notch a is located so that the light from the light emitting unit 25 is received.
FIG. 8 is a diagram illustrating a state where light is reaching a light section. In addition, FIG. 6 shows between two photo interrupters 4a and 4b.
Distance (n + 3/4) P and the circle on the rear end side of the manual ring 3.
The width P / 2 of the notch a and the non-notch b in the annular edge 14
Width P / 2 and circular edge 1 on the rear end side of the manual ring 3
4 illustrates the relationship with the pitch P of the cutout portion a in FIG.
FIG. In addition, the above n means a natural number,
Two photo interrupters 4a, 4 shown in FIG.
b and the annular edge 14 on the rear end side of the manual ring 3.
The relative positional relationship with the notch portion a is described in the photo above.
The interval between the interrupters 4a and 4b is n in (n + 3/4) P.
It corresponds to the case of = 1. Next, FIGS. 7A and 7B show the manual ring 3
2 in the state where is moving in the direction of arrow α in FIG.
Relative output signal from each photo interrupter 4a, 4b
FIG. 9 is a waveform diagram exemplifying a detailed phase relationship, and FIG.
In (a) and (b), the manual ring 3 has an arrow in FIG.
Two photo interfaces in the state of moving in the β direction
Example of relative phase relationship of output signals from raptors 4a and 4b
It is the waveform diagram which is doing. The distance between the two photo interrupters 4a and 4b is (n + 3/4)
P and the annular shape on the rear end side of the manual ring 3.
The width of the notch portion a and the width of the non-notch portion b in the edge portion 14 are both set.
P / 2, and the ring on the rear end side of the manual ring 3
When the pitch of the notch a in the edge 14 is P
In addition, in FIG. 6, the circular ring on the rear end side of the manual ring 3 is
When the edge 14 is moved in the direction of the arrow α in the figure,
Output from the photo interrupter 4a shown in (a) of the figure
The signal is the photo interrupter shown in FIG. 7 (b).
Delayed by 90 degrees in electrical angle compared to the output signal from 4b
State and after the manual ring 3 in FIG.
The circular edge 14 on the end side moved in the direction of arrow β in the figure
In the state, the photo interrupt shown in FIG.
The output signal from the controller 4a is the output signal shown in Fig. 8 (b).
90 electrical degrees compared to the output signal from the toe interrupter 4b
It's just that this kind of signal generator
Where it can be easily understood from the principle of signal generation in
is there. And the two photo interrupters 4a, 4b described above
These output signals are relative to the edge of each signal on the time axis.
Information about the rotation direction of the manual ring 3
And the number of signal edges appearing on the time axis.
Contains information about the amount of rotation of the manual ring 3, and
The number of signal edges in a certain time
Since the information about the rotation speed of the ring 3 is included,
Photo interface according to the rotation of the manual ring 3.
Optical system based on the output signals output from the raptors 4a and 4b
Control of the moving direction and the moving amount of the vehicle through electric signals
It is clear that Therefore, the mani
Photo interrupter according to the rotation of the dual ring 3
Based on the edge signal in the output signal output from 4a, 4b
And a displacement control signal including the moving direction and the moving amount of the optical system.
Can be generated. By the way, the rotation direction and the rotation amount of the manual ring 3
For each fo that is required to generate a signal corresponding to
Time position of the edge of the output signal from the TO interrupter 4a, 4b
As a means to detect the information of the
The output signals from the interrupters 4a and 4b are clock signals.
Output signal from each photo interrupter 4a, 4b
To detect the edge of the
The output signals from the photo interrupters 4a and 4b.
There are two ways to detect the edge of the
Although the method may be used, in the former method the temperature of the circuit element is
Errors may occur due to variations in the degree characteristics
Then, by applying the latter method, each photo interrupter 4
The edges in the output signals from a and 4b are detected.
It is considered preferable to In the following explanation, the manual operation of the manual ring 3
Photointerrupter in photointerrupter structure 4
Between the edges on the time axis of the signals output from 4a and 4b
A pulse with a shorter cycle than the time interval is used as the clock signal.
In the output signal from each photo interrupter 4a, 4b
The edge is to be detected. In addition, the synchronization signal to the camera
If it has a signal generator,
Then, the signal of the horizontal scanning period may be used.
No. FIG. 11A shows the photo interrupter structure 4.
The output signal of the photo interrupter 4a is shown in FIG.
Photointerrupter 4b in the autointerrupter structure 4
The output signal of the photointerrupter is shown in (c) of FIG.
Output from the photo interrupters 4a and 4b in the body 4
The period compared to the time separation between edges on the time axis of the signal
Of the clock signal using the short pulse of
(D) and (e) are the clocks shown in (c) of FIG.
3 shows the edge signal detected by the black signal. 9 shows the manual ring 3 on the time axis of FIG.
When manually operated in the rotation mode as shown in (a)
From the photo interrupter 4a of the photo interrupter structure 4
Output signal {(b) in FIG. 9} and the photo interrupter
Output signal from 4b {(c) in Fig. 9} and manual
Ring 3 is shown in FIG. 1 or FIG. 2 or FIG.
The two flaps when rotated in the direction of arrow α
Edge signals in the output signals from the digital interrupters 4a and 4b.
No. {(b) of Fig. 9} and the manual ring 3 are shown in Fig. 1.
Alternatively, as shown by the arrow β in FIG. 2 or FIG.
Two photo interrupts when rotated in one direction
Edge signals in the output signals from the switches 4a and 4b (see FIG. 9
(E)} and the above at each predetermined time interval
For obtaining the integrated value of the edge signal {(g) in FIG. 9}
It shows a periodic signal for time {(f) in Fig. 9 etc.
You. Photo interrupter in photo interrupter structure 4
Signal level change of the output signal from the controller 4a {(b) in FIG. 9}
Status and output signal from the photo interrupter 4b {9th
The signal level change state of (c) in the figure
Ring 3 in the rotation mode as shown in FIG. 9 (a) on the time axis.
This corresponds to the case of being manually operated. In addition, the photo shown in (b) and (c) of FIG.
Output signals from the interrupters 4a and 4b are output from the light emitting unit 25.
Low level when light reaches the light receiving unit 26
In this state, the light from the light emitting unit 25 has reached the light receiving unit 26.
The state is shown as a high level state. Now, from time to to time tl shown in FIG.
In the section, photo interrupters 4a, 4 at time to
The output signals from b are both high level.
However, at this time, the manual ring 3 is
Since it is rotated in the direction of the arrow α in FIG.
After the time point to, the photo shown in (c) of FIG.
The output signal of the TO interrupter 4b is
It changes to the low level state, and then in Fig. 9 (b).
The output signal of the photo interrupter 4a shown is high.
Change from the level state to the low level state. Conversely, the output of the two photo interrupters 4a, 4b
The signal levels of both signals are initially high.
However, the photo image shown in (c) of FIG.
The output signal of the interrupter 4b changes from high level to low level.
Changes to the level state, and then shown in FIG. 9 (b).
The output signal of the photo interrupter 4a is
2 to change from the low state to the low level state
The signal level of the output signal of the photo interrupter 4a, 4b of
If it is detected that it is changing on the time axis,
The numerical ring 3 is an arrow in FIGS. 1, 2, and 6.
The state of rotating in the direction indicated by α has been detected.
become. Contrary to the above, the output of the two photo interrupters 4a, 4b
When the signal level of the force signal is high at the beginning
First, the photo shown in Figure 9 (b)
The output signal of the interrupter 4a changes from high level to low.
-Level state, and then shown in Fig. 9 (c).
The output signal of the photo interrupter 4b being
To change from the bell state to the low level state, 2
Signal level of output signals of two photo interrupters 4a and 4b
If it is detected that is changing on the time axis,
The manual ring 3 is an arrow in FIGS. 1, 2, and 6.
It is detected that the state of rotating in the direction indicated by mark β is detected.
Becomes When the camera is in manual operating mode
Then, the rotation of the manual ring 3 causes the photo interrupt.
Output from the two photo interrupters 4a and 4b of the structure 4.
The signals shown in (b) and (c) of FIG.
2 Supply to the signal processing unit 11 via the line 17 shown in FIG.
Then, the signal processing unit 11 generates a clock signal with a short cycle.
Two in the photo interrupter structure 4 described above using
In the output signals of the photo interrupters 4a and 4b
Generate an edge signal corresponding to these edges, and
Manual ring based on the relative phase of the edge signal 3
The rotation direction of is detected. 9 (d) and (e) are rotations of the manual ring 3.
FIG. 6 is a diagram in which edge signals for each direction are distinguished and illustrated.
However, this is a convenient method to facilitate the explanation.
Because I used it. Now, in the signal processing unit 11 described above, the manual ring
Regarding the edge signal for each rotation direction of 3,
Plus 1 for each edge signal in the
Minus one for each edge signal in the direction of motion,
Predetermined as illustrated in FIG. 9 (f)
Edges that belong to the same period τ for each fixed period τ
Accumulate the number of signals,
The integrated value for each fixed period τ is shown in (f) of FIG.
Control time to the time position of the leading edge of the periodic signal for timing
The trailing edge of the periodic signal for outputting to the path 7
Reset the integrated value in the previous period τ at the time position of
You. As described above, for each predetermined constant period τ,
The product of the number of edge signals belonging to the same period τ
The integrated value obtained by performing the calculation is the same as the moving direction of the optical system.
It corresponds to the displacement control signal including the motion amount. Of the fixed period mentioned above, which is the integration period of the edge signal
The time length τ is
Rotation of the ring 3 and the pulse motor
Correspondence with the state of displacement of the optical system performed by driving
It can be realized without delay. The camera has a sync signal generator
If provided, the periodic signal for timekeeping described above
You can use the vertical sync signal as
The time length τ of the integration period of the edge signal is 1/60. In Fig. 9 (same for Fig. 10), T1, T2, T3, T4 ...
Is the integration period of the edge signal.
It is a period having a fixed period time length τ. FIG. 9 (g) shows the edges for each predetermined fixed period τ.
The figure shows an example of the numerical value of the integrated value of the partial signal.
The integrated value of the edge signal at T1 is +2, the edge at period T2
Total value of partial signal is 0, total value of edge signal in period T3
Is -2, the integrated value of the edge signal in the period T4 is -3, ...
However, this numerical value is (d) in FIG.
The number of signals shown in (e) is shown in (d) of FIG.
The signal being applied is positive, as shown in Figure 9 (e).
Signal is negative and is shown in Fig. 9 (f).
Sequential period T1, T2, T3, T4 ...
Integrated value for each interval T1, T2, T3, T4, that is, how the optical system moves
The displacement control signal including the direction and the movement amount is sequentially sent to the control circuit 7.
Given. In the control circuit 7, from the signal processing unit 11 the above-mentioned sequential period
Integrated value for each T1, T2, T3, T4…, that is, the moving direction of the optical system
Pulse motor corresponding to the displacement control signal including the
Generate a drive signal used to drive the
Supply to the driver 8. Driving the pulse motor generated by the control circuit 7 described above
The signal is the integrated value for each of the sequential periods T1, T2, T3, T4, ...
Corresponding to, the accumulated value in the rotation direction corresponding to the sign of the accumulated value
The pulse motor is rotated by the number of steps corresponding to
However, the drive signal is
The period to which the edge signal used to obtain the arithmetic value belongs
Is supplied to the motor driver 8 in the next period of
It is amplified by the inverter 8 and used as the drive pulse for the pulse motor.
Through the line 18 shown in FIGS. 1 and 2.
The light is given to the pulse motor of the lens drive unit 9.
The academic system is displaced. In FIG. 2, 24 is the rotary shaft of the pulse motor,
A gear 23 is fixed to the rotary shaft 24 of the. Also, the above
The gear 22 meshes with the gear 23. Rotation axis of gear 22
Both ends of 21 are supported by bearings 28 and 29,
The rotary shaft 21 has a feed screw 30 that is cut.
The portion is screwed into the screw hole of the connecting member 20. As above
The connecting member 20 is fixed to the mounting member 19 of the lens 2.
You. Therefore, as described above, the pulse in the lens driving unit 9
The pulse of the motor drive pulse is supplied to the motor.
When the motor rotates, the lens 2 rotates the pulse motor.
Displacement drive in the direction of arrow X in Fig. 2 according to the direction and the amount of rotation.
Will be moved. By the way, the manual ring 3 can be adjusted manually.
The integrated value for each of the sequential periods T1, T2, T3, T4 ...
The drive pattern of the pulse motor generated based on the integrated value
The frequency of the loose is higher than the response frequency of the pulse motor
Things can happen. Then, as described above, the power generated based on the integrated value is
The drive pulse frequency of the loose motor is
If the frequency is higher than the answer frequency, the pulse motor is correct.
The light stored in the control circuit 7 cannot be rotated.
Information on the position of the academic system and the actual position of the optical system are not aligned
Mating happens. Therefore, in the drive control device of the optical system of the camera of the present invention,
To prevent the problems described above from occurring.
Manual ring 3 for sequential periods T1, T2, T3, T4
The integrated value obtained for each is generated based on that integrated value.
Pulse motor drive pulse frequency
The value is set to a value higher than the response frequency of the
If it is, that is, the manual ring 3 is manually
Therefore, the integrated value obtained for each successive period T1, T2, T3, T4 ...
However, if the value exceeds the predetermined value,
And the integrated value of the edge signal for each predetermined fixed period τ
The corresponding pulse motor drive pulse is
Repetition frequency above the highest frequency that the motor can respond
Not to have a predetermined
The integrated value of the edge signal for each fixed period τ is
The repetition frequency of the generated pulse of the pulse motor is
Do not exceed the maximum response frequency of the pulse motor
Is limited to a certain value, the control circuit 7
It is supplied to the driver 8 and used to obtain its integrated value.
Pulse motor in the period following the period in which the edge signal
To the pulse motor drive pulse
I am enthusiastic. Used in the lens drive system 9 for displacing the optical system
Pulse motor is driven by, for example, two-phase excitation method.
If so, in that case, a two-phase drive signal
Rotation direction and number of steps of pulse motor depending on φ1 and φ2
(Rotation amount) is determined. FIG. 10 shows the above-mentioned sequential periods T1, T2, from the signal processing unit 11.
Integrated value for each T3, T4…, that is, movement direction and movement of optical system
Generated in the control circuit 7 in correspondence with the displacement control signal including the quantity and
State of pulse motor drive signal and pulse motor
Is driven by a two-phase excitation method, for example
FIG. 3 is a diagram exemplifying waveforms of two-phase drive signals φ1 and φ2. FIG. 10 (a) shows the edge signal of each predetermined period.
With the same contents as (f) in FIG. 9 described above, which illustrates the integrated value.
FIG. 10 (b) is the same as that of FIG. 9 already described.
The same periodic signal for timing as (g) is shown. In addition, FIG. 10 (c) shows one specific rotation direction (Platform).
Drive pulse that rotates the pulse motor in the
(D) of Fig. 10 is the above-mentioned specific one rotation direction.
Install the pulse motor in the opposite rotation direction (negative rotation direction).
The drive pulse to rotate is shown, and (e) of Fig. 10 shows the pulse.
Driving one of the two phase drive signals φ1 and φ2 of the motor
Signal φ2, (f) in Fig. 10 shows two-phase drive of pulse motor
The drive signal φ1 of the other phase of the signals φ1 and φ2 is shown.
You. The pal shown in (c) and (d) of FIG.
The drive pulse of the motor depends on the pulse motor used.
Cycle that can be answered, for example, the pulse motor used will respond
A fixed period set near the reciprocal of the highest possible frequency
It is supposed to have. Then, the plastic shown in FIG.
The driving pulse in the direction of rotation of the roller is shown in Fig. 10 (d).
As a general rule, the driving pulse in the negative rotation direction is
Product in the period immediately preceding the period in which the drive pulse was generated.
It is supposed to correspond to the integrated value of the calculated edge signal.
You. That is, the sequential periods shown in (a) of FIG.
Of the integrated value in T1, T2, T3 ...
The integrated value shown in (b) and shown in (c) of FIG.
Drive pulse in the positive direction of rotation and (d) in FIG.
Contrast with drive pulse in negative rotation direction shown
As can be seen, the integrated value of the edge signal in period T1
The drive pulse in the positive rotation direction corresponding to +2 is the period T2.
Is generated in {see (c) of Fig. 10} and the edge in period T2
The drive pulse is generated during the period T3 corresponding to the integrated value 0 of the partial signal.
Not born {see (c) and (d) in Fig. 10}, in period T3
Negative direction of rotation corresponding to the accumulated value of the edge signal of -4
Drive pulse is generated in period T4 (see (d) in FIG. 10).
As shown in FIG. 10 (c) above,
Drive pulse in the positive rotation direction and (d) in Fig. 10
Drive pulse in the negative rotation direction shown in
Is, in principle, one of the periods in which the drive pulse was generated.
Corresponding to the integrated value of the edge signal integrated in the previous period
It has been. However, during the period T8 shown in (a) of FIG.
The integrated value of the edge signal is +6 in (b) of Fig. 10.
However, the edge signal in the period T8 described above
Corresponding to the integrated value of +6, it occurs in the period T9 next to the period T8.
Drive pulses in the positive direction of rotation are
If the integrated value is +4, the integrated value of the edge signal is
Positive rotation to be generated in the next period of the obtained period
Direction 10 as a drive pulse in the same state as the drive pulse
It is shown in FIG. As in the above example, the drive pulse of the pulse motor is
Corresponding to the integrated value of the edge signal used to generate
What is done in the absence state is the pair with the integrated value of the edge signal.
Generated when the drive pulse is generated in the
Frequency of the drive pulse of the pulse motor
When the response frequency is higher than that of the loose motor
Yes, in FIG. 10 described above, a predetermined period τ
It is generated corresponding to the integrated value of the edge signal
The pulse motor used has a response
The example is performed under the assumption that it is the shortest possible cycle.
Therefore, the period in FIG.
Occurred in period T9 corresponding to the integrated value of edge signal +6 in period T8
The drive pulse used can respond to the pulse motor used.
Drive pulse with the shortest period, i.e., edge signal
If the integrated value of is +4, the integrated value of the edge signal
Plus times that should be generated in the period following the period in which
The driving pulse is in the same state as the driving pulse in the rolling direction.
It was. Thus, the drive control device for the optical system of the camera of the present invention
Then, by the manual ring 3 manually, the sequential period T
1, T2, T3, T4 ... Based on the integrated value of the edge signal obtained for each
The frequency of the generated pulse motor drive pulse is
The pulse frequency becomes higher than the response frequency of the motor.
The integrated value that exceeds the number of steps the motor can drive
When it occurs in the signal processing section 11, the control circuit 7
The integrated value is the maximum number of steps that can be driven by the pulse motor.
Integration that can generate drive pulses that can drive pulse motors
The value is automatically changed and the drive pulse corresponding to
Since it is supplied to the motor, it can be operated manually.
The rotation of the manual ring 3
Pulse motor used even for displacement of optics
Was always set near the shortest period it could respond to
Driven by a drive pulse with a constant period
Information on the position of the optical system stored in the control circuit 7.
Therefore, there is no deviation from the actual position of the optical system. The optical system to be adjusted by applying the present invention is
It does not matter whether it is a focus lens or a zoom lens.

【The invention's effect】

As is apparent from the above description in detail, the drive control device for the optical system of the camera of the present invention rotates the manual ring in the focusing operation and the zooming operation to cause the displacement control signal generating means to rotate. Generates a displacement control signal corresponding to the moving direction and the moving amount of the optical system according to the rotation of the manual ring, and the displacement control signal generated by the displacement control signal generating means is set to a predetermined constant value. It is integrated for each time, the drive pulse of the pulse motor is generated corresponding to the integrated value, and the displacement control signal used to obtain the integrated value is generated in the period to which the fixed time belongs. The pulse motor is supplied to the pulse motor in the following period, and the drive pulse of the pulse motor generated corresponding to the integrated value of the displacement control signal at the constant time is the highest frequency that the pulse motor can respond to. In order not to have the above repetition frequency, the above-mentioned integrated value of the displacement control signal for each predetermined constant time, the repetition frequency of the drive pulse of the pulse motor generated corresponding thereto Since the value is limited so that the maximum response frequency is not exceeded, in the present invention, for example, the position of the home position (zero point) when the power is turned on is set as the reference position, and the position of the optical system is driven by the pulse motor. It can be easily controlled by the number of drive pulses used for, and the above-mentioned conventional problems can be satisfactorily solved.
Since the manual operation is performed by the rotating operation of the manual ring, the camera can be manually operated with the same handling feeling as a camera having a mechanical adjustment function by rotating the conventional manual ring. The microprocessor used in the control circuit can occupy less time for inputting operation information, which facilitates information processing, and also reduces the number of forward and reverse rotations of the pulse motor. Since the motor is always driven and rotated at a constant speed, the motor load can be easily designed.

[Brief description of drawings]

FIG. 1 is a block diagram showing a schematic configuration of a drive control device of an optical system of a camera of the present invention, FIG. 2 is an exploded view of a part of a drive control device of an optical system of a camera of the present invention, and FIGS. FIG. 8 is a diagram for explaining the photo interrupter, and FIGS.
The figure is a waveform diagram for explaining the operation. 1 ... Lens mount part of camera housing, 2 ... Part of the lens that is moved by the lens drive part 9 within the lens group of the required configuration provided inside the lens mount part 1 of the camera housing 3 ... Manual ring, 4 ... Photointerrupter structure, 4a, 4b ... Photointerrupter,
5 ... Photoelectric conversion element, 6 ... Automatic focus control circuit (autofocus circuit), 7 ... Control circuit, 8 ... Motor driver, 9 ... Lens drive section, 10 ... Operation section, 11 ... Signal processing , 12 ... Output terminal, 13 ... Front cover in which front balls are stored and fixed, 13a ... Cylindrical part formed at rear end of cover 13, 14 ... Rear end of manual ring 3 Annular edge of a, notch, b ... non-notch, 15 ...
Lens barrel, 16 ... Stopper, 19 ... Mounting member, 20 ... Coupling member, 21 ... Rotating shaft, 22,23 ... Gear, 24 ... Pulse motor rotating shaft, 25 ... Light emitting unit, 26 ... … Light receiving part, 27 …… Gap, 28,29 …… Bearing, 30 …… Feed screw,

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-62-180338 (JP, A) JP-A-63-89825 (JP, A) JP-A-1-264375 (JP, A)

Claims (1)

(57) [Claims] 1. A camera configured such that displacement of an optical system during at least one of a focusing operation and a zooming operation is performed by using a driving force of a pulse motor. Displacement control signal generating means for generating a displacement control signal including information on a moving direction and a moving amount of an optical system in response to rotation of a manual ring operated when the above operation is performed by a manual operation; The displacement control signal generated by the displacement control signal generating means is integrated at predetermined constant time intervals, and when the integrated value is equal to or less than a predetermined value, the integrated value signal is output. When the integrated value is equal to or greater than the predetermined value, the drive signal generating means for outputting a signal having the predetermined value, and the drive signal output from the drive signal generating means It, the optical system of the drive control device for a camera which is adapted to drive the pulse motor during a certain time subsequent to a certain time of the of the drive signal is obtained