JP3535739B2 - Aperture control device for TV camera - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for controlling a diaphragm amount of a lens of a television camera, and more particularly to a device for electrically controlling a diaphragm amount by operating a knob.

[0002]

2. Description of the Related Art For example, in sports broadcasting of TV, each cameraman shoots with a TV camera installed at a plurality of places, and each TV camera monitors a TV screen shot by a video engineer (VE) in a relay vehicle. Various adjustments are performed by operating the adjustment device connected to the. Here, regarding the aperture amount of the lens of the television camera, the aperture amount is automatically controlled by an automatic aperture control device built in the camera side so that the incident light amount has a preset value (for example, f = 5.6). However, it is possible to switch to manual aperture control as appropriate according to the determination of VE and manually control the aperture amount so as to obtain a desired brightness by operating the knob of the adjusting device.

The knob is usually attached to a potentiometer, and its mechanical rotation angle is limited. Generally, the diaphragm is closed with the maximum operation amount of left rotation and the diaphragm is opened with the maximum operation amount of right rotation. Often. In such a manual control, the mechanical rotation angle of the potentiometer itself is reflected as the diaphragm amount. On the other hand, when performing automatic lens aperture control by the automatic aperture control device, the aperture amount of the camera is constantly changed according to the amount of incident light, and at this time, the knob and the potentiometer connected to the knob have a rotation angle thereof. Has not changed.

Therefore, when the automatic aperture control device is operating, the mechanical rotation angle of the potentiometer itself is not reflected as a value corresponding to the aperture amount on a one-to-one basis. Further, generally, in consideration of operational convenience, a knob operation can be performed during the automatic aperture control to increase or decrease the target value of the incident light amount.

Specifically, a value corresponding to the position of the midpoint of the mechanical rotation angle range of the potentiometer is held at a preset light quantity (for example, f = 5.6), and the knob is rotated to the left for maximum operation. As for the amount of light, the amount of light that is reduced by 1 STOP from the set value (for example, the amount of light becomes half of the set value)
Also, the knob is the maximum operation amount for clockwise rotation, and is 1 from the set value.
The amount of light when the aperture is opened as far as STOP (for example, the amount of light is set to 2
It has a function to hold).

[0006]

However, in such a conventional aperture control device for a television camera, as described above, the mechanical rotation of the potentiometer when the automatic aperture control device is operating. Since the angle itself is not reflected as the aperture amount, the following problems occur.

For example, when it is desired to use the automatic aperture control device so as to hold the light amount with the aperture opened by about 1 STOP from a preset value, the potentiometer is operated to the full right rotation. However, in this state, if the automatic diaphragm control device is stopped and switched to the manual control, the diaphragm is immediately opened corresponding to the knob position of the manual control, and the screen suddenly changes to a white screen. On the contrary, if you want to use the automatic aperture control device to keep the amount of light with the aperture closed about 1 STOP from the preset value, operate the potentiometer fully to the left, but in this case as well, use manual control. When switched, the diaphragm is fully closed corresponding to the manual control, and suddenly changes to a black screen.

That is, since the correspondence between the potentiometer and the mechanical rotation angle is different between the automatic control and the manual control,
There is an inconvenience that it becomes difficult to adjust the light amount before and after the switching. In view of this point, in order to smoothly shift to manual control from the above-mentioned automatic control state without causing a screen shock (a sudden change in the screen), there is a system that employs the following method. In this device, first, when the control is switched from the automatic mode to the manual mode, a knob whose knob rotation angle corresponds to the aperture amount in the manual mode is 1: 1 is operated, and the control output is automatically controlled. Only when the value matches the given value, the aperture control data itself is switched from the automatic control value to the manual control value.

However, in the above method, even if the control method itself is switched from automatic control to manual control, the actual aperture control value itself does not immediately switch, and it takes time to adjust the manual control value to the automatic control value, and In the case where the aperture control value is smoothly switched, attention is paid to the rotation operation of the knob itself. Therefore, in this method, it is not possible to quickly shift from automatic control to manual aperture control when necessary.

Further, although the knob is being operated, the switching from the automatic control to the manual control is delayed, and the diaphragm amount does not change during this period, which causes a feeling of strangeness. A method of using a rotary encoder for the knob part has been conventionally known as a means for smoothly and promptly switching from an automatic control screen to a manual control screen while avoiding a screen shock.
The rotary encoder has no limitation on the mechanical rotation angle, and it is difficult to grasp the limit point of the throttle control that triggers the next operation especially on the opening side, and it is difficult to handle even when the manual control is performed. There are problems such as.

That is, when the aperture control, which is left to the automatic control, has to be corrected by the manual control under a certain condition, and the manual control itself is found to be the limit, the image is taken by the camera. The use (on-air) of the recorded image is temporarily stopped and the image is transferred to another camera.
In the meantime, it is usual to switch the camera control and restart the operation of the camera when a desired state is reached.

It is desired to inform the person who operates the camera as early as possible on the information on the camera operation when using a plurality of cameras. At the time of adjustment before on-air, it is possible to grasp the limit point by visual information by looking at the value of the aperture amount displayed on the main body of the adjustment device or by displaying the aperture amount or its limit point on the viewfinder. However, since the VE constantly makes adjustments while monitoring the shooting screen while it is on air, it is practically difficult to monitor the display of the adjustment device body, and the viewfinder screen shows the amount of aperture. Displaying the information is not preferable because the display of the information impairs the captured image information and affects the adjustment work.

Therefore, in the rotary encoder type as well as in the potentiometer type, it is required that the limit point can be grasped by the operation feeling of the knob.
The present invention has been made in view of such a conventional problem, and can perform switching from automatic aperture control to manual aperture control smoothly and quickly without occurrence of a screen shock, and limits the aperture amount. It is an object of the present invention to provide a diaphragm control device for a television camera, which can be grasped by operating the knob.

[0014]

Therefore, in the invention according to claim 1, the aperture amount of the lens of the television camera is changed.
Knob and operation restriction means for restricting operation of the knob
And, by operating the knob, before the operation of the knob
Based on the amount of aperture
Of the TV camera that controls the aperture amount according to the direction and amount
In the diaphragm control device, the operation restricting means is at least
The same amount of aperture can be set by operating the knob in one direction
When it detects that the limit set amount corresponding to
Driven to mechanically operate the knob in the same operating direction
Knob to regulate and allow operation in the opposite direction
To reduce the amount of squeezing the knob from the limit setting amount
Return operation in the direction
The return operation so that operation in both operating directions is allowed.
That, characterized in that.

Further, the invention according to claim 2 is characterized in that the operation regulating means is provided for each of two operation directions of the knob which are opposite to each other. Further, in the invention according to claim 3, an automatic aperture control device for controlling the aperture amount is provided so that the incident light amount is feedback-controlled to the target value, and the automatic aperture control by the automatic aperture control device is switched to the manual aperture control. At this time, the aperture amount is controlled to be amplified by a knob operation with the aperture amount controlled by the automatic aperture control immediately before switching as a reference.

Further, in the invention according to claim 4, there is provided an automatic aperture control device for controlling the aperture amount so that the incident light amount is feedback-controlled to a target value, and the knob operation is performed during the automatic aperture control by the automatic aperture control device. By doing
It is characterized in that the target value is increased or decreased with respect to the target value of the incident light amount before the knob operation.

Further, in the invention according to claim 5, the operation restricting means includes a first gear connected to a knob that is rotationally operated, an arm whose one end is pivotally supported, and the arm. A second gear that is rotatably supported by the other end of the second gear and that meshes with the first gear by a second gear that meshes with the first gear and a rotation operation in a direction in which the operation of the knob is restricted. Of the arm that swings in one direction via the gear of
A stopper that regulates the amount of swing in the same direction, and a position where the arm is free to switch between a position where the arm is engaged with the tooth of the second gear and a position where the arm is disengaged, and the position where the arm is engaged. Then, the rotation of the second gear that is interlocked with the rotation operation in the direction in which the operation of the knob is restricted is restricted to restrict the rotation operation of the knob in the same direction, and the rotation of the second gear in the opposite direction to the above. For operation, the second gear is rocked together with the arm, and a rotation restraining lever arranged so as to be disengaged from the second gear is provided.

[0018]

According to the first aspect of the invention, the amount of aperture of the lens can be smoothly and quickly increased / decreased from the value before the operation of the aperture by the knob operation, and the aperture opening side or It is possible to obtain an effect that the limit set amount of at least one of the closed sides can be sensuously grasped through the knob operation.

According to the second aspect of the present invention, it is possible to obtain an effect that the limit set amounts on both the opening side and the closing side of the diaphragm can be sensuously grasped through the knob operation. Further, according to the invention of claim 3, when the automatic aperture control is switched to the manual aperture control, the aperture amount can be amplified and controlled by the knob operation with the aperture amount controlled by the automatic aperture control immediately before the switching as a reference. It is possible to prevent an abrupt change in the aperture amount that occurs before and after switching, and to prevent the occurrence of screen shock.

Further, according to the invention of claim 4, there is an effect that the automatic aperture control can be performed to a desired brightness by performing the knob operation during the automatic aperture control. Further, according to the invention of claim 5, when the knob is rotated clockwise in the direction in which the operation is restricted, for example, in the aperture opening direction, the knob rotates integrally with the knob having the first gear and meshes with the first gear. The arm swings around the support shaft via the second gear, and the swing is restricted at a predetermined position by the stopper. At the same time, the aperture amount of the lens is controlled in the opening direction according to the operation of the knob.

Before the throttle amount reaches the limit set value in the opening direction, the second gear rotates while meshing with the first gear while the movement of the arm is restricted. When it reaches the limit set value of, the rotation restraining lever is driven so as to mesh with the second gear, whereby the rotation of the second gear is restricted, and at the same time, the first gear and this The operation of the integrated knob in the aperture opening direction is restricted. As a result, it is possible to reliably know that the limit set value has been reached by operating the knob.

On the other hand, in the reverse direction, when the knob is operated to return in the closing direction of the throttle amount, the second gear oscillates in the opposite direction with the arm in response to the reverse rotation of the first gear. As a result, the meshing between the second gear and the rotation restraining lever is smoothly disengaged, and the reverse rotation operation is allowed without applying a special external force for disengaging the meshing.

[0023]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. 1 to 4 show the configuration of an embodiment of an aperture control device for a television camera of the present invention. In the figure, the first gear 1 is provided below the knob for adjusting the diaphragm.
And an arm 3 whose one end is swingably connected to a support shaft 2, and a second gear 4 meshing with the first gear 1 is rotatably supported at the other end of the arm 3. .

Here, the arm 3 is provided so as to swing smoothly with respect to the support shaft 2, and the second gear 4 is supported so as to rotate with a certain friction with respect to the arm 3. There is. On both outer sides of the arm 3, the arm 3
A pair of stoppers 5 and 6 for restricting the swinging range of are provided. Further, the rotation restraining lever 8 is provided so as to smoothly rotate about the support shaft 7, and the tension spring 9 that biases the rotation restraining lever 8 with the torque of counterclockwise rotation.
Is provided. The plunger 12 of the suction solenoid 13 is attached to one end (the right end in the figure) of the rotation restraining lever 8.
Are connected. The left rotation range of the rotation inhibiting lever 8 is limited by the stopper 11, and the right rotation range is limited by the stopper 1.
Limited by 0.

Although not shown, the knob and the first
A rotary encoder is connected to the rotary shaft of the gear 1 of the gear, and the aperture amount of the TV camera is increased or decreased according to the rotary operation direction and the rotary operation amount of the knob from the aperture amount before the operation of the knob detected by the rotary encoder. A control circuit for controlling and a drive system are provided. In the present embodiment, the throttle amount is controlled in the opening direction by the clockwise rotation operation, and when it is detected that the set limit value in the aperture amount opening direction, that is, the opening has been reached, the suction solenoid 13 is driven and the plunger is driven. 12 is adapted to clockwise rotation inhibiting lever 8 is pulled until it hits the stopper 1 1.

Next, the operation of this structure will be described. Figure 1
Indicates an initial state in which the spindle 2, the center of the second gear 4 and the center of the first gear 1 are aligned. At this time, the attraction solenoid 13 is de-energized and the plunger 12
Is extended, and the rotation restraining lever 8 is stopped in a state of being in contact with the stopper 10 by the restoring force of the tension spring 9.

When the knob is rotated rightward from this state, the first gear 1 rotates rightward together with the knob. At this time, the arm 3 is provided so as to smoothly swing with respect to the support shaft 2 within the range of the stoppers 5 and 6 , and the second gear 4 has some friction with respect to the arm 3. Since it is supported so as to rotate, the second gear 4 does not rotate and the arm 3 swings to the right.
Since the swing width of the arm 3 is limited by the stopper 5, the arm 3 comes into contact with the stopper 6 to stop the swing, as shown in FIG. At the same time, the aperture is controlled in the opening direction according to the operation of the knob, but it is opened (limit setting value).
The solenoid 12 is maintained in the OFF state before reaching, and the rotation preventing lever 8 is not meshed with the second gear 4. Therefore, when the knob is further rotated to the right from the state where the arm 3 is in contact with the stopper 6 , the second gear 4 that meshes with the first gear 1 starts to rotate and the rotation of the first gear 1 is continued. While the second gear 4 is rotating, the operation of the knob in the aperture opening direction is permitted.

From the state shown in FIG. 2, when the knob is further rotated to the right to open the diaphragm, the opening is detected and the suction solenoid 13 is energized. This allows
As shown in FIG. 3, the plunger 12 pulls in the right end portion of the rotation restraining lever 8 in the drawing, and rotates the rotation restraining lever 8 in the clockwise direction in the drawing. As a result, the left end portion of the rotation restraining lever 8 shown in the drawing engages with the teeth of the rotating second gear 4 while being engaged with the teeth of the second gear 4 and rotates to the position where the stopper 11 abuts and stops. It should be noted that the rotation restraining lever 8 is provided with the stopper 1 as the second gear 4 tries to rotate.
Since it is strongly pressed against 1, it acts to prevent swinging. Further, since the second gear 4 and the first gear 1 mesh with each other, if the rotation of the second gear 4 stops, the first gear 1 will inevitably stop.

Therefore, the VE operating the knob
Can detect that the aperture has been opened by the feel of the knob. When the rotation inhibiting lever 8 comes into contact with the teeth of the second gear 4, the left end of the rotation inhibiting lever 8 operates so as to be pulled into the bottom of the teeth of the second gear 4, so that the attraction solenoid 13 is It is not necessary to continue energizing, and energization can be stopped to achieve a power saving configuration.
However, even if the energization is not stopped, if the knob is rotated in the opposite direction, it is detected that the aperture has not been opened, and the energization of the plunger is turned off.

As described above, the arm 3 is provided so as to swing smoothly when the knob is rotated in the opposite direction, that is, the direction in which the diaphragm is closed from the state where the diaphragm is at the open end. Since the gear 4 is supported so as to rotate with some friction with respect to the arm 3, the second gear 4 does not rotate, and the arm 3 swings to the left in the drawing. With the movement of the arm 3, the meshing between the rotation inhibiting lever 8 and the second gear 4 is released smoothly and quickly,
The rotation restraining lever 8 is returned to the initial position shown in FIG. 1 by the restoring force of the tension spring 9. As described above, when the knob reaches the open end of the diaphragm, it does not rotate further toward the open side but can rotate smoothly and quickly toward the closed side.

Focusing on the above-mentioned operation with respect to the related operation of the knob and the diaphragm, if the diaphragm is manually controlled, the diaphragm will open as the knob rotates to the right, and when it is opened, the knob cannot rotate any further to the right. , Counterclockwise rotation, which is the opposite direction, can be rotated smoothly and quickly,
Therefore, control is performed in the direction of closing the diaphragm.

In the above, the one provided with the operation restricting means for restricting the operation in the opening direction of the diaphragm has been described, but the rotation is restrained so as to be symmetrical with respect to the line connecting the first gear 1 and the support shaft 2. Lever 8, tension spring 9, stopper 10,
Stopper 11, plunger 12, suction solenoid 13
It is also possible to provide operation restricting means configured to restrict the operation of the knob in the closing direction further when the closing side is detected in the diaphragm closing direction. With such a configuration that the operation amount in both the aperture opening direction and the closing direction is regulated, the function of manual aperture control operation is the same as that of the aperture control device using a normal potentiometer.

The above is the description when the aperture is manually controlled. During the above operation, there is no element that specifies the unique position of the knob with respect to the aperture amount. Therefore, the above operation is established regardless of the position of the knob when the apparatus is activated. Next, a state in which the automatic diaphragm adjustment function is operating will be described.

The automatic aperture adjustment function performed by the automatic aperture control device generally refers to a function of always controlling the aperture so that the amount of light incident on the camera becomes a preset value. In this function, as described above, even if the knob position itself does not change, the diaphragm amount controlled automatically is constantly changing. In this embodiment, since there is no element that specifies the unique position of the knob for the diaphragm amount controlled by the automatic diaphragm control, when the automatic diaphragm adjustment function is operating, the diaphragm amount that constantly changes is controlled. It should be associated with the position. In other words, even if the knob itself does not move at all in appearance, it always corresponds to the diaphragm amount controlled automatically.

Therefore, when the knob is rotated, a mechanism for adjusting the diaphragm amount corresponding to the knob rotation with respect to the diaphragm amount controlled by the automatic diaphragm adjusting function can be configured. In the mechanism, the conventional potentiometer holds a value corresponding to the position of the midpoint of the mechanical rotation angle range at a preset light amount, and when fully left, the light amount narrowed by 1 STOP from the preset value, At the full right, it is basically the same as the mechanism that holds the amount of light with the aperture stopped about 1 STOP from the preset value. It is to be noted that, under the operation of the automatic diaphragm adjusting function, it is basically required that the suction solenoid 13 is not energized even when the diaphragm is open, whereas under manual control, the rotation of the knob causes the diaphragm to be rotated. When is opened, it is possible to energize the suction solenoid 13 and control the rotation of the knob to stop.

Further, a case where the automatic diaphragm adjusting function is stopped from the operating state will be described. The automatic iris adjustment function
Generally, since the function is to control the diaphragm so that the amount of light incident on the camera becomes a preset value, the diaphragm constantly changes even if the position of the knob itself does not change, as described above. . In the present embodiment, similarly to the above, even if the knob itself does not move visually, it means that it always corresponds to the aperture amount under automatic control, so when this is stopped from the operating state of the automatic aperture adjustment function. Is associated with the knob position by the aperture amount controlled at the moment when the automatic aperture adjustment function stops. The aperture control from there can be performed in the same manner as when the aperture is controlled by the above-mentioned means.

Although the arm, gear, stopper, rotation inhibiting lever, plunger, solenoid, tension spring, etc. are used in the above embodiment, stopping the rotation of the knob in one direction is the limit setting amount of the diaphragm. Other mechanism may be used as long as it can be performed at any position when it is reached and does not restrain the movement in the opposite direction. Further, the determination of opening / closing of the diaphragm may not be based on electric control.
Further, the detector to which the knob and the first gear 1 are connected has no limitation on the mechanical rotation angle, and the specifications are not limited to those other than the rotary encoder as long as the rotation direction and the rotation amount can be obtained. Absent.

Further, when the aperture reaches the limit set amount by the one-way operation of the knob, the operation is restricted in the same direction as in the above embodiment, and the operation torque is stepwise. It may be configured to increase rapidly.

[Brief description of drawings]

FIG. 1 is a mechanism diagram showing an embodiment of a diaphragm control device for a television camera of the present invention, particularly a diagram showing an initial state.

FIG. 2 is a mechanical view showing an embodiment of a diaphragm control device for a television camera according to the present invention, and particularly showing a state in which a knob is rotated to the right.

FIG. 3 is a mechanical view showing an example of an embodiment of a diaphragm control device for a television camera of the present invention, in particular showing a state in which a knob is prevented from rotating to the right.

FIG. 4 is a mechanical view showing an example of an embodiment of a diaphragm control device for a television camera of the present invention, particularly a view showing a state in which the knob is rotated to the left from the position in which the knob is restrained.

[Explanation of symbols]

1st gear 2 spindles Three arms 4 second gear 5 stopper 6 stopper 7 spindle 8 rotation restraint lever 9 Extension spring 10 stopper 11 stopper 12 Plunger 13 Suction solenoid

Claims (5)

(57) [Claims] 1. The amount of diaphragm of a lens of a television camera is changed.
Knob and operation restriction means for restricting operation of the knob
And, by operating the knob, before the operation of the knob
Based on the amount of aperture
Of the TV camera that controls the aperture amount according to the direction and amount
In the aperture control device, the operation restricting means is a knob in at least one operation direction.
The limit setting amount that corresponds to the same operation direction
It is driven when it is detected that the
Mechanically restricts operation in the same operation direction, but in the opposite direction
The operation of is engaged with the knob to allow it, and the knob is moved in the direction in which the throttle amount decreases from the limit setting amount.
When the return operation is performed, the engagement is released and both knob operations are performed.
A iris control device for a television camera, wherein the iris control device performs a return operation so that a directional operation is permitted . 2. The aperture control device for a television camera according to claim 1, wherein the operation restricting means is provided for each of two operation directions of the knob which are opposite to each other. 3. An automatic aperture control device for controlling the aperture amount so as to perform feedback control of the incident light amount to a target value, and when the automatic aperture control by the automatic aperture control device is switched to the manual aperture control, immediately before the switching. The aperture control device for a television camera according to claim 1, wherein the aperture amount is controlled to be increased or decreased by a knob operation with reference to the aperture amount controlled by the automatic aperture control. 4. An automatic aperture control device for controlling the aperture amount so as to perform feedback control of an incident light amount to a target value, and by performing the knob operation during the automatic aperture control by the automatic aperture control device, before the knob operation. The aperture control device for a television camera according to any one of claims 1 to 3, wherein the target value is increased or decreased with respect to the target value of the incident light amount. 5. The operation restricting means includes a first gear connected to a knob that is rotationally operated, an arm whose one end is swingably supported, and the other end of the arm. A second gear that is axially supported by the first gear and a second gear that meshes with the first gear and a second gear that meshes with the first gear by a rotational operation in a direction in which the operation of the knob is restricted. A stopper that regulates the amount of swinging of the arm that swings in the same direction, and a position where the arm is restrained by the stopper are freely switchable between a position where the arm meshes with the teeth of the second gear and a position where the arm disengages. Therefore, at the meshing position, the rotation of the second gear that is interlocked with the rotation operation in the direction in which the operation of the knob is restricted is restricted to restrict the rotation operation of the knob in the same direction, and For rotation operation in the opposite direction to the above 5. A rotation restraining lever arranged so that the second gear swings together with the arm to disengage from the second gear. A diaphragm control device for a television camera according to any one of 1.