JP2003279832A - Lens system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lens system capable of adjusting a focus from the position of a focus lens set by automatic focusing (AF) even at the time of switching from the AF to manual focusing (MF) for instance and adjusting the focus by effectively using the MF and the AF by setting a position for which the target position of a previous time is changed for a change amount equivalent to the operation position change amount of the operation member of the MF as a new target position at the time of the MF in the lens system for setting the target position at the time of the MF and at the time of the AF and moving the focus lens to the target position by motor drive. <P>SOLUTION: The CPU 30 of a lens device 12 motor-drives the focus lens FL on the basis of focus command signals supplied from a focus demand 28 at the time of the MF and on the basis of the high frequency components of video signals at the time of the AF. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lens system, and more particularly to a lens system in which the focus adjustment of a taking lens can be switched between manual focus adjustment using a focus demand and automatic focus adjustment.

[0002]

2. Description of the Related Art In order to adjust the focus of a camera lens, an autofocus (A
F) and the cameraman operate the focus operation member to manually focus (M Focus)
There is F).

Generally, a consumer video camera is designed to select either the AF mode or the MF mode by a predetermined mode changeover switch and to perform the focus adjustment in either the AF mode or the MF mode. It is hard to think that the focus adjustment with only the AF is possible with the TV camera of the
It is preferable that the focus adjustment can be performed according to the operation of the MF by performing the operation of (see JP-A-8-2.
9665).

A controller called a focus demand may be used for the focus adjustment of the MF in the television camera. In this case, the focus ring provided in the focus demand is rotated to operate the focus ring. The focus lens of the photographing lens is moved by a motor drive to a position corresponding to the rotation position of.

[0005]

However, when the focus demand is used for the focus adjustment of the MF as described above, an absolute position command signal indicating the position of the focus lens is normally sent from the focus demand to the lens device. It is given and the focus lens moves to the absolute position. For this reason, when AF is executed, a difference occurs between the designated position of the focus demand and the position of the focus lens set by AF. At this time, if AF is switched to MF, the focus lens moves to the designated position of the focus demand even if the focus demand is not operated, and AF focus adjustment becomes meaningless. .

The present invention has been made in view of the above circumstances, and when the AF mode is switched to the MF mode, the focus lens system is moved from the position of the focus lens system set by the AF system according to the operation amount of the MF system thereafter. Accordingly, it is an object of the present invention to provide a lens system capable of performing focus adjustment by effectively using AF and MF.

[0007]

In order to achieve the above object, the invention according to claim 1 is such that a target position of a focus lens for focus adjustment mounted on the taking lens is set to a manual operation of an operating member. MF set based on
Means, an AF means for automatically setting the target position on the basis of information on a subject to be photographed, the MF means or the AF means.
In a lens system including a focus lens driving unit that sets the focus lens by a motor drive to a target position set by the MF unit, the MF unit sets the MF unit or the AF unit when setting a new target position. The new target position is a position displaced from the previous target position or the current position of the focus lens by a change amount corresponding to the change amount of the operation position of the operation member since the last target position was set by the means. It is characterized by setting as.

The invention described in claim 2 is the same as claim 1.
In the invention described in (1), the MF means detects an operation position of the operation member as an operation amount from a predetermined reference position, and a previous target position when setting a new target position. The operation amount of the operation member when setting is set and the current operation amount are detected by the operation amount detection means, and the operation member from the time when the previous target position is set by the difference between the detected operation amounts. The operation position change amount detecting means for detecting the operation position change amount, and the change amount corresponding to the operation position change amount detected by the operation position change amount detecting means to the previous target position or the current position of the focus lens. Target position setting means for setting the position displaced with respect to the new target position.

The invention described in claim 3 is the same as claim 1
In the invention described in (1), the MF means is a detection means for detecting an operation position of the operation member as an operation amount from a predetermined reference position, and an operation position change for detecting the operation amount as an operation position change amount. An amount detection means and a reset means for resetting the operation position change amount detected by the operation position change amount detection means when a new target position is set, and the operation position at that time as the reference position; A target for setting a new target position at a position displaced from the previous target position or the current position of the focus lens by a change amount corresponding to the current operation position change amount detected by the operation position change amount detection means. And a position setting means.

According to a fourth aspect of the invention, there is provided a focus demand including the lens device including the focus lens driving means and the target position setting means, and the operation member and the operation position change amount detecting means. 4. The lens system according to claim 3, wherein the focus demand resets the operation position change amount each time a signal indicating the operation position change amount detected by the operation position change amount detecting means is transmitted to the lens device. It is characterized in that the reset means is provided.

According to a fifth aspect of the invention, there is provided a focus demand including the lens device including the focus lens driving means and the target position setting means, and the operation member and the operation position change amount detecting means. The lens system according to claim 3, wherein the reset means comprises:
Reset instruction means included in the lens device, the reset instruction means for instructing the focus demand to reset the operation position change amount each time a new target position is set by the target position setting means, and the focus demand. Reset execution means provided in
When a reset instruction is given by the reset instruction means, a reset execution means for resetting the operation position change amount detected by the operation position change amount detection means is provided.

The invention according to claim 6 is the same as claim 1.
In the invention described in (1), the MF means is a detection means for detecting an operation position of the operation member as an operation amount from a predetermined reference position, and corresponds to a target position for setting the operation amount by the MF means. When the target position is detected by the AF unit and the target position detection unit that detects the absolute value, the operation amount detected by the target position detection unit at that time is set by the AF unit. Reference position changing means for changing the reference position so that the operation amount corresponds to the target position, and a target position corresponding to the operation amount detected by the target position detecting means when setting a new target position. Is set as a new target position.

According to the present invention, when the target position is set at the time of manual focus (MF) and auto focus (AF) and the focus lens is moved to the target position by the motor drive, the operation member of the MF is operated at the time of MF. Since a new target position is set to a position displaced from the previous target position or the current position of the focus lens by a change amount corresponding to the operation position change amount of, the focus lens is moved to the target position. For example, when switching from AF to MF, focus adjustment can be performed from the position of the focus lens set by AF, and MF and AF can be effectively used to perform focus adjustment.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the lens system according to the present invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 is a perspective view showing an embodiment of a television camera system in which the lens system according to the present invention is used. As shown in FIG.
The television camera 10 is composed of a lens device 12 and a camera body 14, and the television camera 10 includes a platform 18 on a pedestal Dolly 16.
Supported by. The platform 18 has two operation rods 22, 2
3 is extended, and a zoom demand 26 and a focus demand 28, which are connected to the lens device 12 by cables, are attached to the ends of the operation rods 22 and 23, respectively.

The zoom demand 26 is provided with a thumb ring 26A that is rotatable in both directions from a reference position. When the thumb ring 26A is rotated, the operation amount (rotation direction and rotation amount) from the reference position. ) Corresponding to the zoom command signal from the zoom demand 26 to the lens device 12
The zoom of the photographing optical system (photographing lens) of the lens device 12 moves to the wide side or the tele side.

The focus demand 28 is provided with a rotatable focus ring 28A. When the focus ring 28A is rotated, a focus command signal corresponding to the operation amount (rotation direction and rotation amount). Is given to the lens device 12 from the focus demand 28, and the focus of the taking lens of the lens device 12 moves to the near side or the infinity side.

FIG. 2 is a block diagram showing the overall configuration of the lens system according to the present invention. In the lens system shown in the same figure, for example, a well-known focus lens (group) is used as a photographing optical system (photographing lens) of the lens device 12.
An FL, a zoom lens (group) ZL, an iris I, a wobbling lens (group) WL, and the like are arranged, and the subject light incident on the photographing lens is imaged on the image sensor surface of the camera body 14.

Each lens FL, ZL, WL and iris I
Are driven by the corresponding focus motor FM, zoom motor ZM, wobbling motor WM, and iris motor IM (each lens moves in the optical axis direction, and the iris I changes the opening amount). FM,
ZM, WM, and IM are focusing amplifiers FA, respectively, according to drive signals given from a CPU 30 built in the lens device 12 via a D / A converter 32.
It is driven by a zoom amplifier ZA, a wobbling amplifier WA, and an iris amplifier IA.

On the other hand, various signals can be exchanged between the focus demand 28 and the CPU 30 through serial communication interfaces (SCI) 34 and 36. For example, the details of the focus demand 28 to the CPU 30 will be described. As will be described later, a focus command signal based on the turning operation of the focus ring 28A is given.

The CPU 30 executes a manual focus (MF) process based on the focus command signal given from the focus demand 28. That is, a focus command signal given from the focus demand 28,
Focus potentiometer FP to A / D converter 3
Based on the position signal indicating the current position of the focus lens FL, which is given via 8 the drive signal for driving the focus motor FM as described above is given to the focus amplifier FA via the D / A converter 32. , The focus lens FL is moved to the target position set based on the focus command signal.

Further, from the zoom demand 26 to the CPU
A zoom command signal for commanding the moving speed (target speed) of the zoom lens ZL according to the amount of rotation of the thumb ring 26A is given to 30 via the A / D converter 38. still,
Focus demand 28 for zoom demand 26
Similarly to the above, various signals may be exchanged with the CPU 30 by communication. Based on the zoom command signal given from the zoom demand 26 and the position signal showing the current position of the zoom lens ZL given from the zoom potentiometer ZP via the A / D converter 38, the CPU 30 performs the above-described operation. The drive signal for driving the zoom motor ZM is passed through the D / A converter 32 to the zoom amplifier ZA.
The zoom lens ZL is moved at the target speed instructed by the zoom command signal.

Regarding the iris I, generally, an iris command signal for instructing the setting position (aperture value) of the iris I is given from the camera body 14 to the CPU 30.
The reference numeral 30 drives the iris motor IM so that the aperture value instructed by the command signal is obtained while the rotational position of the iris motor IM is detected by the iris potentiometer IM as the setting position of the iris I as in the above. The drive signal is output to the iris amplifier IA.

On the other hand, regarding the wobbling lens WL,
A drive signal is not output based on a command signal from the outside, but a drive signal for wobbling at the time of autofocus, which will be described later, is transmitted from the CPU 30 to the wobbling amb WA.
Is output to. Further, the wobbling motor WM is, for example, a pulse motor, and a potentiometer for feeding back the position of the wobbling lens WL is not installed.

Further, in the present lens system, for example, the lens device 12 is provided with an AF switch S1, and the AF switch S1 is used for autofocus (A
The F) mode and the manual focus (MF) mode can be switched. In the MF mode, the focus lens FL is motor-driven by the MF processing (details will be described later) based on the focus command signal from the focus demand 28 as described above.

On the other hand, in the AF mode, the focus lens FL is motor-driven by the AF process based on the subject information, and the focus lens FL is automatically set to the in-focus position.

The AF mode in the present embodiment is a continuous AF mode in which AF processing, which will be described in detail later, is continuously performed. For example, the so-called one-way AF processing is completed in one focusing operation. Different from shot AF. Hereinafter, the AF mode in this embodiment will be referred to as an AF continuous mode. In the AF continuous mode according to the present embodiment, when the focus ring 28A of the focus demand 28 is operated, the processing automatically switches to the MF process, and the focus lens FL is driven based on the focus command signal from the focus demand 28 to focus the focus. Ring 28
When the operation of A is stopped, the AF process is restarted.

Here, the lens device 1 of the present lens system
2 is provided with a focus evaluation value detection circuit, and the focus evaluation value detection circuit is provided with a video signal (luminance signal) for video display.
Is input from the camera body 14, and a focus evaluation value for evaluating the degree of focusing is detected based on the video signal. The video signal input from the camera body 14 is, for example, N obtained by imaging the subject image formed by the photographing optical system by the image sensor of the camera body 14.
This is a TSC video signal. The focus evaluation value is a value indicating the level of contrast (sharpness) of the image, and its detection method is conventionally known in contrast type AF.

FIG. 2 shows a focus evaluation value detection circuit. The video signal obtained from the camera body 14 is
Only a high frequency component is extracted by the high pass filter (HPF) 40 and converted into a digital signal by the A / D converter 42. Then, of the high-frequency components converted into digital signals, the gate circuit 44 extracts signals only within a predetermined focus area set within the shooting range. A video signal other than the signal from the A / D converter 42 is directly input to the gate circuit 44, and a signal in the focus area only is extracted using the synchronization signal in the video signal. The signals of the high frequency components extracted by the gate circuit 44 are integrated by the adding circuit 46 for each field, and the signal obtained by the integration indicates the degree of focusing (high or low contrast) on the subject in the focus area. The focus evaluation value is read by the CPU 30. The method of detecting the focus evaluation value from the video signal is not limited to the above case.

When the AF process is executed in the AF continuous mode, a drive signal for driving the focusing motor FM is generated by the CPU 30 based on the focus evaluation value, and the drive signal is generated as in the case of the MF. Is output to the focus amplifier FA and the focus lens FL is output.
Moves to the in-focus position. Specifically, the CPU 30 outputs a drive signal for driving the wobbling motor WM to D /
The focus evaluation value is acquired from the focus evaluation value detection circuit (adding circuit 46) while appropriately outputting to the wobbling amplifier WA via the A converter 32 to move the wobbling lens WL back and forth (waving) in the optical axis direction. (For example, it is acquired for each field). As a result, the focus position of the photographing optical system moves back and forth, and the same focus evaluation value is detected when the focus lens FL is moved back and forth from the current set position. The CPU 30 determines whether or not the focus evaluation value is maximum at the current position of the focus lens FL based on the focus evaluation value acquired during the wobbling. If the focus evaluation value is the maximum, the focus is obtained, and the focus lens FL is stopped at the focus position. On the other hand, if the focus evaluation value is not maximum, whether the focus position is in the infinity direction or the close-up direction than the current position from the magnitude relationship of the focus evaluation values acquired during wobbling, that is, the focus evaluation value is Determine the direction of increase. Then, a drive signal is output to the focusing amplifier FA to move the focus lens FL in the determined direction. Thus wobbling lens W
By repeating the wobbling of L and the movement of the focus lens FL, the focus lens FL is automatically set to the in-focus position.

Next, the MF process using the focus demand 28 will be described in detail. FIG. 3 shows the structure of the focus demand 28. As shown in FIG. 3, the rotary ring of an endless incremental rotary encoder 62 is connected to the focus ring 28A of the focus demand 28, and 28
When A is rotated, a pulse is output from the rotary encoder 62 at every constant rotation amount.
Although detailed description is omitted, for example, as is generally known, a pulse having different phases of the A-phase and the B-phase is output from the rotary encoder at a constant rotation amount. The direction of rotation is detected by the advance or delay of the phase of the B-phase pulse with respect to.

The pulse output from the rotary encoder 62 is input to the counter 64, and the focus ring 2
The value of the counter 64 (counter value) is incremented by 1 each time 8A rotates in the forward direction by a certain amount, and the focus ring 28A
The counter value of the counter 64 is decremented by 1 every time the is rotated in the reverse direction by a certain amount. The counter value counted by the counter 64 is the C value mounted on the focus demand 28.
Read by the PU 60. For example, the CPU 60 sequentially reads the counter value from the counter 64 and resets the count value each time the counter value is read. Then, the counter values read from the counter 64 are integrated. The focus ring 2 is calculated by the integrated value (hereinafter, this value is also referred to as a counter value)
The operation amount of the focus ring 28A from the reference position is detected with the predetermined operation position of 8A as the reference position. Further, the focus ring 2 detected by the CPU 60
The operation amount (counter value) of 8A can be appropriately reset, and the operation amount is reset at a desired operation position of the focus ring 28A, that is, by making the operation amount 0, the desired operation position becomes the reference position. The operation amount of the focused ring 28A can be detected. Furthermore,
Instead of setting the reference position by resetting, the operation amount at that time is set to a desired value at the desired operation position of the focus ring 28A, and the counter value of the counter 64 is added to the value of the operation amount. It is also possible to set the reference position so that the desired operation position of the focus ring 28A becomes a desired operation amount by moving. Note that, instead of resetting the counter value each time the counter value of the counter 64 is read as described above, the desired operation position of the focus ring 28A is set as the reference position by resetting the counter value of the counter 64 at a desired time. It is also possible to detect the manipulated variable of the focus ring 28A by the count value itself of the counter 64.

As described above, the focus demand 28 is constructed so that the desired operation position of the focus ring 28A is used as a reference position and the operation amount of the focus ring 28A from the reference position can be detected. The configuration and processing for detecting the operation amount of the focus ring 28A in the focus demand 28 is not limited to the above case. Further, the configuration and processing are not limited to particular ones, and the following description will be made assuming that the operation amount of the focus ring 28A from the desired reference position in the focus demand 28 is detected by the counter value as described above.

Further, the CPU 30 controls the operation amount (count value) of the focus ring 28A detected as described above.
The focus command signal having the designated value is transmitted to the lens device 12 through the SCI 34.

On the other hand, the CPU 30 of the lens device 12 receives the focus command signal transmitted from the SCI 34 of the focus demand 28 through the SCI 36, and acquires a command value (of the focus ring 28A of the focus ring 28A) acquired by the focus command signal as will be described in detail later. Position (target position) where the focus lens FL should be set based on the operation amount)
Set the position command value indicating. The position command value set here is an absolute position command value indicating an absolute value corresponding to the set position (target position) of the focus lens FL. Then, the difference between the signal value indicating the current position of the focus lens FL obtained from the focusing potentiometer FP and its position command value is obtained, and the difference value (or the value obtained by multiplying the difference value by a predetermined coefficient) is calculated. As the drive signal, the focus amplifier F is transmitted through the D / A converter 32 as described above.
Output to A. As a result, the focus lens FL is set at the position corresponding to the position command value. The focus command signal transmitted from the focus demand 28 to the CPU 30 of the lens device 12 does not have to be the value of the operation amount (counter value) of the focus ring 28A itself,
In order to simplify the explanation, it is assumed that the value of the operation amount itself of the focus ring 28A is transmitted as the focus command signal.

Next, the first embodiment of the MF processing until the CPU 30 sets the position command value (absolute position command value) will be described. First, a case where the position command value is continuously set by the MF processing (a case where the MF processing is continuously performed) will be described with reference to FIG. In the following, when simply referring to the position command value, CP
It shall mean the absolute position command value set in U30. In the case of setting a new position command value, the operation position of the focus ring 28A when the previous position command value (currently set position command value) is set is shown in FIG.
It is assumed that the operation amount of the focus ring 28A detected at the point a indicated by the ● mark in (A) is the value of the point a indicated by the ● mark in FIG. It should be noted that the operation amount is set such that the operation amount at the reference position is zero (O point in FIG. 7B), with a predetermined operation position (O point in FIG. 9A) of the focus ring 28A as a reference position. Is set to.

Then, the position command value set at that time is the value at the point a shown by the ● mark in FIG. 7D, and the position of the focus lens FL set corresponding to it is the position in FIG.
It is assumed that it was at point a indicated by a black circle. The position command value is
It is set to a value within a range corresponding to the movable range of the focus lens FL (range from the closest end to the infinite end).

Then, from this state, the focus ring 28
It is assumed that A is rotated. Then, when setting a new position command value, it is assumed that the operation position of the focus ring 28A is changed to the point b shown by the cross mark in FIG. Further, at this time, it is assumed that the operation amount of the focus ring 28A becomes the value of the point b shown by the cross mark in FIG.

At this time, a new position command value is set as follows. First, the difference between the operation amount at point a in FIG. 7B detected at the time of setting the previous position command value and the operation amount at point b in FIG. That is,
Operation position change amount Δab from point a to point b in FIG.
Is calculated as shown in FIG. Subsequently, the operation position change amount Δab is added to the position command value at the point a shown in FIG. 7D to obtain the value at the point b indicated by the cross mark in FIG. Then, the value at the point b is set as a new position command value. Since the position command value is set to the same value until the next update, the previous position command value when setting a new position command value is equal to the currently set position command value. As described above, when the operation position change amount of the focus ring 28A is added to the previous position command value,
The operation position change amount of the focus ring 28A may be added to the currently set position command value.

In this way, by adding the operation position change amount of the focus ring 28A from the previous position command value setting to the previous (current) position command value, and setting that value as a new position command value, The focus lens FL moves by a variation amount corresponding to the operation position variation amount.

Next, a case where AF processing is performed during MF processing will be described with reference to FIG. Note that such a situation occurs, for example, when the AF switch S1 (see FIG. 1) is set to the AF continuous mode in which the MF operation is prioritized and the focus ring 28A is repeatedly operated in the AF continuous mode. The description will be made assuming this case. First, the focus ring 28A as in FIG.
5A, the operation amount of the focus ring 28A detected at that time is the value of the point a shown by a black circle in FIG. 5B. At this time, the previous position command value is set to the value of the point a indicated by the ● mark in FIG.
Is set to point a indicated by the ● mark in FIG. Then, the operation of the focus ring 28A is stopped and M
It is assumed that the processing of F is switched to the processing of AF, and the focus lens FL is moved to the point c indicated by a circle in FIG. After that, the focus ring 28A is operated again, and the operation position of the focus ring 28A is changed to the point b shown by the cross mark in FIG. 5A as in the case of FIG. 4, and the operation of the focus ring 28A at this time is changed. It is assumed that the amount reaches the value at the point b indicated by x in FIG.

In this case, a new position command value is set as follows. First, the difference between the operation amount at point a in FIG. 7B detected at the time of setting the previous position command value and the operation amount at point b in FIG. The operation position change amount Δab from point a to point b in FIG. 7B is obtained as shown in FIG. Then, the operation change amount Δab is added to the position command value at the point c indicated by the circle mark (D) in the figure to obtain the value at the point b indicated by the cross symbol in the figure (D).
Then, the value at the point b is set as a new position command value. Here, the value at point c in FIG. 7D is a position command value corresponding to the position of the focus lens FL after AF processing, and the position command value at point a in FIG. This is a value obtained by adding a value corresponding to the amount of movement of the moved focus lens FL.

In this way, the amount of change in the operating position of the focus ring 28A from the previous setting of the position command value is calculated as M
Instead of adding to the position command value at the time of processing F, it is added to the position command value corresponding to the position of the focus lens FL after AF processing, and the value is set as a new position command value, so that the operation is performed. It is possible to displace the focus lens FL from the position after the AF processing by the amount of change corresponding to the amount of position change.

In the AF process, the focus lens FL is set while setting the position command value as in the MF process.
Is moved to the position corresponding to the position command value, the position command value at point c in FIG. 5D moves the focus lens FL to point c in FIG. 5E by AF processing. This is the position command value actually set for the purpose. Therefore, when setting a new position command value in the MF process, the focus ring 28 is set to the previously set position command value including the AF process, that is, the current position command value.
If the operation position change amount of A is added, a new position command value can be obtained as described above.

When the MF processing of the first embodiment described with reference to FIGS. 4 and 5 is summarized, the MF processing continues in the first embodiment as in the example of FIG. In either case or when the AF process is performed during the MF process as in the example of FIG. 5, when setting a new position command value during the MF process, the previous position command value is set. The operation position change amount of the focus ring 28A from the time when is set is added to the previously set position command value, that is, the currently set position command value regardless of whether the MF process or the AF process is performed. , And the value obtained by the addition is set as a new position command value.

In the case of the above description, the focus ring 2
The operation position change amount of 8A is the operation amount of the focus ring 28A when the previous position command value was set during MF processing (point a in FIG. 5B) and the new position command value. The operation amount of the focus ring 28A (see FIG.
Although the difference from the point b in (B) is used, for example, in consideration of AF modes other than the AF continuous mode in the present embodiment in which the MF operation is prioritized, the AF continuous mode in the present embodiment may also be used. Including this, it is preferable to define the operation position change amount of the focus ring 28A as follows. For example, when the operation of the MF is not prioritized in the AF mode, that is, the processing of the MF is not executed even if the focus ring 28A is operated in the AF mode, and the focus lens FL is operated according to the operation of the focus ring 28A unless the mode is switched to the MF mode. If the focus ring 28A is not operated, the focus ring 28A is operated in the AF mode, and the operation position change amount caused by the operation is considered.
Therefore, when the AF mode is switched to the MF mode, a situation occurs in which the focus lens FL moves due to the operation position change amount that occurred during the AF mode. Therefore, in order to prevent such a situation from occurring in any form of AF mode, only the operation of the focus ring 28A performed when the MF processing is effectively executed is performed at the above-mentioned operation position. MF to reflect in the amount of change
The operation of the focus ring 28A performed when the processing of No. is not executed effectively (when the processing of the MF is disabled) invalidates the operation position (operation amount) of the focus ring 28A by the operation at this time. It is preferable to treat it as one that has not been processed. Specifically, for example, M
When setting a new position command value in the process of F, the previous position command value is set regardless of whether the previous (current) position command value was set by the process of MF or the process of AF. Focus ring 2
The operation position change amount of 8A is added to the previous position command value to obtain a new position command value. By doing this, the focus ring 2 performed when the MF processing is disabled
The operation of 8A can be invalidated.

In the above description, the focus ring 2
Although the operation position change amount of 8A is added to the previous position command value to obtain a new position command value, the operation position change amount is not added to the previous position command value, but the focus potentiometer FP is used. A new position command value may be a value obtained by adding the operation position change amount to the detected current position of the focus lens FL (a signal value indicating the current position).

Next, the CP in the first embodiment described above.
The MF processing procedure of U30 will be described with reference to the flowchart of FIG. First, the CPU 30 performs a required initial setting (step S10), and then sets the position command value (absolute position command value) F_ctrl set in the CPU 30 to 0, and the focus demand signal from the focus demand 28 is used as the focus command signal of the focus ring 28A. The operation amount (relative position command value indicating the set position of the focus lens FL as a relative value) F_b is set to 0 (step S12).

Next, after the processing other than the AF continuous mode (step S14) is executed, the AF switch S1 is used to
It is determined whether or not the F continuous mode is turned on (step S16). If NO is determined, the process returns to step S14. On the other hand, if YES is determined, it is next determined whether or not the operation of the focus demand 28 (operation of the focus ring 28A) is stopped (step S18). If YES is determined here, wobbling is performed by driving the wobbling lens WL (at this time, the focus evaluation value is acquired from the focus evaluation value detection circuit, for example, for each field). Whether or not the focus evaluation value is maximum at the current position of the focus lens FL based on the focus evaluation values acquired in between,
That is, it is determined whether or not the focus is achieved, or the direction in which the focus evaluation value increases when the focus is not achieved, that is, the focus direction (step S20). Then, it is determined whether or not focus is achieved (step S22), and if NO is determined, in order to move the focus lens FL in the focus direction by a predetermined amount F_af, the current absolute position command value F_ctrl is set to F_af. The value obtained by adding is set as a new absolute position command value F_ctrl (step S24). Then, the process proceeds to step S34. If YES in step S22, the process returns to step S14.

In step S18, NO, that is,
When it is determined that the focus ring 28A of the focus demand 28 is being operated, the relative position command value F_dem (the amount of operation of the focus ring 28A) transmitted as a focus command signal from the focus demand 28 next.
Is received (step S26). Then, the difference F_dif between the relative position command value F_b at the time of setting the previous absolute position command value and the relative position command value F_dem is obtained (step S28). Further, the current relative position command value F_dem is substituted as the previous relative position command value F_b when the next new absolute position command value is obtained (step S30). Then, add the above difference F_dif to the previous (current) absolute position command value F_ctrl,
The value is set as a new absolute position command value F_ctrl (step S32).

Next, in step S34, the current position of the focus lens FL is read from the focusing potentiometer FP and the value is set as F_pos (step S34). Then, step S24 or step S32
The position error F_err between the new absolute position command value F_ctrl set in step 1 and the current position F_pos of the focus lens FL is calculated (step S36), and the position error F_err is used as the drive signal for focusing via the D / A converter 32. It outputs to the amplifier FA for (step S38). As a result, the process returns to step S14, and the processes from step S14 are repeatedly executed.

The MF processing in the above-described first embodiment includes the operation amount of the focus ring 28A (including the processing in the focus demand 28 (from the reference position when a predetermined operation position is fixed to the reference position). Operation amount of the focus ring 28A), calculation of the operation position change amount of the focus ring 28A from the setting of the previous position command value, and calculation of a new position command value. be able to. In the above description, the process of is performed by the focus demand 28, and a focus command signal indicating the operation amount (relative position command value) of the focus ring 28A from the focus demand 28 is C of the lens device 12.
It is transmitted to the PU 30. Then, based on the operation amount, the processing of is performed by the CPU 30 of the lens apparatus 12, but the processing is not limited to this, and each of the processing of to the focus demand 28 and the lens apparatus 12 is performed.
It can be performed by any of the CPU 30.

For example, the output of the rotary encoder 62 of the focus demand 28 or the output of the counter 64 is directly transmitted as a focus command signal from the focus demand 28 to the CPU 30 of the lens device 12, and CP
In U30, it is also possible to perform the above-mentioned processes (1) to (3) based on the received focus command signal.

Further, the above processing is performed in the focus demand 28, and the lens device 12 uses the operation position change amount of the focus ring 28A as a focus command signal.
It is also possible to transmit the data to the CPU 30 and to perform the above processing in the CPU 30.

In the focus demand 28, all the above processes (1) to (3) are performed, and the position command value (absolute position command value) indicating the target position of the focus lens FL is transmitted to the CPU 30 of the lens device 12 as a focus command signal, and the CPU 30 is operated. It is also possible to set the value of the focus command signal as the position command value without performing special processing in.

Next, the second embodiment of the MF processing until the CPU 30 sets the position command value (absolute position command value) will be described. In the first embodiment, when the reference position of the focus ring 28A is set to a predetermined position, the difference between the operation amounts of the focus ring 28A detected by the above processing will be used without changing the reference position. Focus ring 2 by processing
Although the operation position change amount of 8 A is calculated,
In the embodiment, each time a new position command value is set, the operation amount of the focus ring 28A at that time is reset (zero), and the operation position at that time is changed to the reference position. The operation amount of the focus ring 28A detected by
The above processing is unnecessary.

For example, in the case where a new position command value is set by the MF process, the focus ring used when the previous position command value (currently set position command value) is set by the MF process or the AF process. It is assumed that the operation position of 28A is at point a shown by ● in FIG. 7A, and the operation amount of focus ring 28A detected at that time is the value of point a shown by ● in FIG. 7B. . The operation amount when the position command value was set last time was detected using the operation position (point O in FIGS. 9A and 9B) when the position command value was set before that as the reference position. It is the operation amount. The position command value set at that time is indicated by a mark a in FIG.
It is a value of a point, and it is assumed that the position of the focus lens FL set corresponding to it is at point a shown by the ● mark in FIG. In this case, first, the operation amount at the time of setting the previous position command value is reset, and the operation position at the point a in FIG. 10A is set as the reference position O ′, and the value at the point a in FIG. Change to zero.

Next, from this state, the focus ring 28A
It is assumed that is rotated. Then, when setting a new position command value, the operation position of the focus ring 28A is changed to the point b indicated by the mark X in FIG. 7A, and at this time, the operation amount of the focus ring 28A changes the point a to the reference position. Then, it is assumed that the value at the point b indicated by the mark x in FIG.

At this time, the operation amount at the point a in FIG. 9B calculated by the processing in the first embodiment, and
The difference from the operation amount at the point b in FIG. 7B, that is, the operation position change amount Δab shown in FIG. 6C matches the value of the operation amount at the point b in FIG. Therefore, the operation amount of the focus ring 28A detected when the position command value is newly set is set as the operation position change amount Δab, and the above-mentioned a shown in FIG.
By adding to the position command value of the point, a new position command value of the point b indicated by the mark x in FIG.

By resetting the operation amount of the focus ring 28A each time a new position command value is set, the operation amount of the focus ring 28A detected when setting a new position command value is the same as the previous operation amount. The operation position change amount from the time of setting the position command value is indicated, and the operation amount is added to the previous (current) position command value, and the value is set as a new position command value. Similar to the embodiment, the focus lens FL moves by the change amount corresponding to the operation position change amount. As with the first embodiment, the operation amount of the focus ring 28A (the operation position change amount) is not added to the previous position command value to obtain a new position command value, but the focus potentiometer FP is used. A new position command value may be obtained by adding to the detected current position of the focus lens FL (a signal value indicating the current position).

As described above, in the second embodiment, only the processing of the processings 1 to 3 shown in the first embodiment is unnecessary and is performed. Then, the above processing is performed by the focus demand 28, and the processing of is performed by the CPU 30 of the lens device 12, but as in the first embodiment,
Each of the processes of (1) and (2) can be performed by either the focus demand 28 or the CPU 30 of the lens device 12.

For example, the output of the rotary encoder 62 of the focus demand 28 or the output of the counter 64 is directly transmitted as a focus command signal from the focus demand 28 to the CPU 30 of the lens device 12, and CP
In U30, the above process may be performed based on the received focus command signal.

Further, both of the above processes are performed in the focus demand 28, and the position command value (absolute position command value) indicating the target position of the focus lens FL is transmitted to the CPU 30 of the lens device 12 as a focus command signal, and the CPU 30. It is also possible to set the value of the focus command signal as the position command value without performing special processing in.

For resetting the operation amount of the focus ring 28A, a focus command signal is sent to the CPU 3 of the lens device 12 on the focus demand 28 side.
It may be carried out when it is transmitted to 0, or it may be carried out by a reset instruction of the CPU 30 when a new position command value is set in the CPU 30 of the lens device 12. For example, the above processing is performed by the focus demand 28.
In this case, the focus demand 28 resets the operation amount each time the focus command signal is transmitted to the CPU 30 of the lens apparatus 12, and the case of C of the lens apparatus 12 is performed.
Each time the PU 30 sets a new position command value, it sends a reset signal to the focus demand 28. When the reset signal is received, the focus demand 28
It is considered that the operation amount is reset.

Next, a third embodiment of the MF processing until the CPU 30 sets the position command value (absolute position command value) will be described. In the third embodiment, in the MF processing, the operation amount (focus command signal) detected with a predetermined operation position of the focus ring 28A as a reference position is set as in the first and second embodiments. The relative position command value is not recognized as an absolute position command value, but the focus lens FL is recognized as an absolute position command value indicating the target position to be set, and when a new position command value is set by the AF process, the focus ring at that time is set. 28
The reference position is changed so that the operation amount of A becomes the position command value set at that time.

For example, in the case where a new position command value is set by the MF process, the operation position of the focus ring 28A when the previous position command value is set by the MF process is indicated by a ● mark in FIG. 8A. It is assumed that the operation amount of the focus ring 28A detected at the point a is the value of the point a indicated by a black circle in FIG. It should be noted that the operation amount is set such that the operation amount at the reference position is zero (O point in FIG. 7B), with a predetermined operation position (O point in FIG. 9A) of the focus ring 28A as a reference position. Is set to. Then, the position command value set at that time is the value at the point a indicated by the ● mark in the same figure (D), and that value is equal to the value at the a point in the same figure (B), and is set correspondingly. It is also assumed that the position of the focus lens FL is at the point a indicated by the ● mark in FIG.

Next, without switching to AF processing,
Suppose that the operation position of the focus ring 28A becomes a point b shown by X in the figure (A), and the operation amount of the focus ring 28A detected at that time is changed to a point b shown by X in the figure (B). If the manipulated variable is used as a new position command value, a new position command value equal to that added to the previous position command value by the operation position change amount Δab shown in FIG. That is, as in the first and second embodiments, the focus lens FL is displaced by the operation position change amount Δab.

On the other hand, the position command value of the previous time is set to the value of point a shown by ● in the figure (D) by the processing of MF, and the focus lens FL is set to point a shown by the ● in the figure (E). After the setting, the focus ring 28A stops operating and the MF
It is assumed that the processing of (1) is switched to the processing of AF. And
It is assumed that the position command value is changed to the point c indicated by a circle in FIG. 7D by the AF processing, and the focus lens FL is moved to a point c indicated by a circle in FIG.

In this case, when the position command value is newly set by the AF process, the operation amount of the focus ring 28A at that time is changed to the new position command value. That is, as shown in (A) and (B) of the same figure, the reference position is changed to the O'point so that the value of the point a of the same figure (B) becomes the value of the c point of the same figure (D). .

After that, the focus ring 28A is operated again, and the operation position of the focus ring 28A is changed to the point b shown by the mark X in FIG. 7A, and the operation amount of the focus ring 28A at this time is changed. (B) b marked with x
Suppose the value of a point is reached.

At this time, as the operation amount at the point b, the operation position change amount (Δab in the same figure (C)) from the setting of the previous position command value (point c in the same figure) is set to the previous position. It matches the one added to the command value. Therefore, if the operation amount of the focus ring 28A (value at point b in FIG. 7B) detected when a new position command value is set as it is as a new position command value, the position command value will be (D) b indicated by X mark
The value becomes the value of the point, and the focus lens FL moves to the point b indicated by the mark x in FIG. That is, the focus lens FL moves from the position set by AF by a change amount corresponding to the operation position change amount of the focus ring 28A after AF.

From the above, in the third embodiment, only the processings 1 to 3 shown in the first embodiment that are unnecessary are performed. Then, the above processing is performed by the focus demand 28,
In the CPU 30 of the lens device 12, the operation amount (absolute position command value) of the focus ring 28A given as the focus command signal from the focus demand 28 is directly set as the position command value. However, it is also possible to perform the above processing in the CPU 30 of the lens device 12, for example, the output of the rotary encoder 62 of the focus demand 28 or the output of the counter 64 is directly used as a focus command signal from the focus demand 28 to the CPU 30 of the lens device 12. Send CPU
It is also possible to perform the above processing at 30 based on the received focus command signal.

Since the operation amount of the focus ring 28A is detected by using an endless rotary encoder, the detected operation amount (count value) is a counter or a CPU.
When the operation amount of the focus ring 28A is set to the relative position command value as in the first and second embodiments, the value is returned to 0 when the value exceeds the value that can be processed by the process shown in FIG. As shown in (), with respect to the change in the operation position of the focus ring 28A in a certain direction, the value (count value) indicating the operation amount is returned to 0 when the maximum value is reached. On the other hand, as in the third embodiment, the focus ring 28A
When the operation amount of is set as the absolute position command value,
It is preferable to limit the value indicating the operation amount to the range of the value corresponding to the position within the moving range of the focus lens FL with respect to the change of the operation position of the focus ring 28A in a certain direction as shown in FIG.

Next, the CP in the third embodiment described above.
The MF processing procedure of U30 will be described with reference to the flowchart of FIG. Note that the above processing is performed in the focus demand 28.

First, the CPU 30 carries out a process other than the AF continuous mode (step S52) after performing necessary initial settings (step S50), and then determines whether or not the AF continuous mode is turned on by the AF switch S1. Is determined (step S54). If NO is determined, the process returns to step S52. On the other hand, if YES is determined, it is next determined whether or not the operation of the focus demand 28 is stopped (step S5).
6). If YES is determined here, the wobbling lens WL is driven to perform wobbling (at this time, the focus evaluation value is determined from the focus evaluation value detection circuit by, for example, 1).
(Obtained for each field), based on the focus evaluation value acquired during wobbling, whether the focus evaluation value is the maximum at the current position of the focus lens FL, that is, whether the focus is in focus or not, The direction in which the focus evaluation value increases, that is, the focus direction is determined (step S5).
8). Then, it is determined whether or not the focus is achieved (step S6).
0), when NO is determined, a value obtained by adding F_af to the current absolute position command value F_ctrl is added to the new absolute position command value F_ctrl in order to move the focus lens FL by a predetermined amount F_af in the focusing direction. (Step S6)
2). Then, the process proceeds to step S68. If YES is determined in step S60, the AF end signal and the current absolute position command value F_ctrl are transmitted to the focus demand 28, and the current operation amount of the focus ring 28A in the focus demand 28 (absolute position command value). Is changed to the transmitted absolute position command value F_ctrl (step S64). Then, the process returns to step S52.

NO in the above step S56, that is,
When it is determined that the focus ring 28A of the focus demand 28 is operated, the absolute position command value F_ctrl transmitted as the focus command signal from the focus demand 28 is received next (step S66). Then, the received absolute position command value F_ctrl is set as it is as a new absolute position command value F_ctrl.

Next, the process proceeds to step S68, the current position of the focus lens FL is read from the focusing potentiometer FP and the value is set to F_pos (step S).
68). Then, a position error F_err between the new absolute position command value F_ctrl set in step S62 or step S66 and the current position F_pos of the focus lens FL is calculated (step S70), and the position error F_err is used as the drive signal in the D / A. Focusing amplifier FA via converter 32
(Step S72). As a result, the process returns to step S52, and the processes from step S52 are repeatedly executed.

As described above, in the above embodiment, as the AF method, the focus evaluation value is obtained based on the video signal obtained by the image pickup device of the camera body, and the focus lens FL is adjusted so that the focus evaluation value becomes maximum. Although the case of the contrast method of setting the position has been described, the present invention can be applied to the following contrast method or a method different from the contrast method.

For example, in the above embodiment, the wobbling lens WL is wobbled to determine whether or not the focus evaluation value is maximum at the current position of the focus lens FL. However, wobbling is performed. Instead, a plurality of image pickup elements arranged at positions with different optical path lengths (all the image pickup elements may be dedicated to AF, and an image pickup element for generating a video signal for image display may be a plurality of image pickup elements for AF). The present invention can also be applied to a contrast method using (1).
In this method, a focus evaluation value is obtained for each video signal on the basis of a plurality of video signals obtained from a plurality of image pickup devices having different optical path lengths in the same manner as in the above embodiment, and the focus evaluation values are compared in magnitude. It is determined whether or not focus is obtained at the current position of the focus lens FL, and if not, whether the focus position is in the infinite direction or the close-up direction than the current position of the focus lens FL. R.

The present invention can be applied even when the active method is adopted as the AF method. For example, in the active method, the measurement light is emitted from the light emitting unit to the subject, and the measurement light reflected by the subject is received by the light receiving unit, so that the distance to the subject can be determined from the principle of triangulation and the round trip time of the measurement light. To be measured. Then, the focus lens is set at a position corresponding to the measured distance. The measurement wave used in the active method is not limited to light and may be radio waves, sound waves, or the like.

The present invention can be applied to the case where AF is performed by combining both the contrast method and the active method.

In the above embodiment, the case where the focus ring 28A of the focus demand 28 is used to operate the MF has been described, but the present invention can be applied to the MF.
The operating member of is not limited to this. For example, a handy type shooting lens has a focus ring (operation ring) arranged around the normal front lens, and when the focus ring is rotated, the focus lens can be driven by a mechanical mechanism. However, a focus ring having the same structure as the M
The present invention can be applied to a case where the F operation member is used and the rotation position (operation position) thereof is electrically detected similarly to the above-described embodiment to drive the focus lens by the motor.

[0083]

As described above, according to the lens system of the present invention, the target position is set during the manual focus (MF) and the auto focus (AF), and the focus lens is moved to the target position by driving the motor. In this case, at the time of MF, a new target position is set by setting a position displaced from the previous target position or the current position of the focus lens by a change amount corresponding to the operation position change amount of the operating member of the MF, and setting the target. Since the focus lens is moved to the position, for example from AF to M
Even when switching to F, focus adjustment can be performed from the position of the focus lens set by AF,
The focus adjustment can be performed by effectively using the MF and AF.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of a television camera system in which a lens system according to the present invention is used.

FIG. 2 is a block diagram showing an overall configuration of a lens system according to the present invention.

FIG. 3 is a diagram showing a structure of a focus demand.

FIG. 4 is an explanatory diagram used for explaining MF processing according to the first embodiment.

FIG. 5 is an explanatory diagram used to describe MF processing according to the first embodiment.

FIG. 6 is an M of the CPU according to the first embodiment.
It is the flowchart which showed the processing procedure of F.

FIG. 7 is an explanatory diagram used for describing MF processing according to the second embodiment.

FIG. 8 is an explanatory diagram used for describing MF processing according to the second embodiment.

FIG. 9 is a diagram showing a change in an operation amount with respect to a rotation position of a focus ring.

FIG. 10 is a CPU according to a third embodiment.
5 is a flowchart showing a processing procedure of MF.

[Explanation of symbols]

10 ... Television camera, 12 ... Lens device, 14 ... Camera body, 26 ... Zoom demand, 28 ... Focus demand, 28A ... Focus ring, FL ... Focus lens, ZL ... Zoom lens, WL ... Wobbling lens, 3
0 ... CPU, 60 ... CPU, 62 ... Rotary encoder, 64 ... Counter, S1 ... AF switch

Claims (6)

[Claims] 1. An MF means for setting a target position of a focus lens for focus adjustment mounted on the taking lens based on a manual operation of an operating member, and an automatic MF means for setting the target position on the basis of information about a subject to be taken. In a lens system including AF means for setting and focus lens driving means for setting the focus lens to a target position set by the MF means or the AF means by a motor drive, the MF means sets a new target position. At the time of setting, the previous target position or the current position of the focus lens is changed to the previous target position or the current position of the focus lens by a change amount corresponding to the change amount of the operation position of the operation member since the previous target position was set by the MF unit or the AF unit. The lens system is characterized in that the position displaced relative to it is set as a new target position. Beam. 2. The MF means, an operation amount detecting means for detecting an operation position of the operation member as an operation amount from a predetermined reference position, and a previous target position when setting a new target position. The operation amount of the operation member when set and the current operation amount are detected by the operation amount detecting means, and the operation member from the time when the previous target position is set by the difference between the detected operation amounts. An operation position change amount detecting means for detecting an operation position change amount, and a change amount corresponding to the operation position change amount detected by the operation position change amount detecting means with respect to the previous target position or the current position of the focus lens. The lens system according to claim 1, further comprising: a target position setting unit that sets the position displaced by the new target position as the new target position. 3. The MF means is a detection means for detecting an operation position of the operation member as an operation amount from a predetermined reference position, and an operation position change amount for detecting the operation amount as an operation position change amount. A detection unit, a reset unit that resets the operation position change amount detected by the operation position change amount detection unit when a new target position is set, and sets the operation position at that time as the reference position; A target position which is set as a new target position at a position displaced from the previous target position or the current position of the focus lens by a change amount corresponding to the current operation position change amount detected by the position change amount detecting means. The lens system according to claim 1, further comprising setting means. 4. The lens system according to claim 3, comprising a lens device including the focus lens driving unit and the target position setting unit, and a focus demand including the operation member and the operation position change amount detecting unit. The focus demand includes the reset unit that resets the operation position change amount each time a signal indicating the operation position change amount detected by the operation position change amount detection unit is transmitted to the lens device. The lens system of claim 3 characterized. 5. The lens system according to claim 3, comprising a lens device including the focus lens driving unit and the target position setting unit, and a focus demand including the operation member and the operation position change amount detecting unit. The reset unit is a reset instruction unit provided in the lens device, and instructs the focus demand to reset the operation position change amount each time a new target position is set by the target position setting unit. Reset instruction means and reset execution means provided in the focus demand, wherein the reset instruction means resets the operation position change amount detected by the operation position change amount detection means when there is a reset instruction. The lens system according to claim 3, further comprising execution means. 6. The MF means is a detection means for detecting an operation position of the operation member as an operation amount from a predetermined reference position, and the operation amount is the M value.
A target position detection unit that detects an absolute value corresponding to the target position set by the F unit, and an operation amount detected by the target position detection unit at that time when the target position is set by the AF unit. , A reference position changing means for changing the reference position so that the operation amount corresponds to the target position set by the AF means, and a target position detecting means for setting a new target position. The lens system according to claim 1, further comprising target position setting means for setting a target position corresponding to the operated amount as a new target position.