JP2005215290A - Light intensity adjusting device, optical device, and photographing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a light intensity adjusting device capable of preventing the deterioration of an MTF by small diaphragm diffraction, of enhancing the controllability of a diaphragm, and of saving a space, and provide an optical device and a photographic device having the light intensity adjusting device. <P>SOLUTION: In the light intensity adjusting device having: a plurality of diaphragm blades which form an opening; a diaphragm blade drive means for relatively moving the diaphragm blades; an ND filter which separately moves from the diaphragm blades; and an ND filter drive means for moving the ND filter to the opening, it includes a common actuator for driving the diaphragm blade drive means and the ND filter drive means and constituted so that the actuator operates only the ND filter drive means first and operates the diaphragm blade drive means so that the opening becomes from an opened state to a closed state at a stage that the opening is covered with the ND filter. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a light amount adjustment device suitable for a photographing device such as a video camera or a digital still camera, an optical device (lens barrel) having the light amount adjustment device, and a photographing device.

  A diaphragm device mounted on a conventional video camera or the like and used as a light amount adjusting device has two diaphragm blades that move relative to each other in the direction perpendicular to the optical axis, and the diaphragm blades are a seesaw type with a single rotary actuator. It is known to control a rotational position and an amount of rotation (rotation angle) by driving through a drive lever and detecting a magnetic pole change on the outer peripheral surface of the actuator rotor by a Hall element.

  As such a diaphragm device, for example, in Patent Document 1, if an ND filter is attached to one of the diaphragm blades and the subject is bright, if the aperture diameter becomes too small, image quality deterioration due to diffraction and the depth of focus are reduced. Since the movement of dust due to the increase becomes a problem, the ND filter attached to the aperture blade protrudes into the aperture diameter forming notch of the aperture blade so as to prevent an extremely small aperture. What has been proposed is proposed.

Further, as in Patent Document 2, using the diaphragm device described above, an ND filter that moves separately from the diaphragm blades is provided, and the position of the diaphragm of the seesaw type drive lever and the mounting position of the ND filter are set in the radial direction of the seesaw type drive lever. It has been proposed to change the moving speed of the diaphragm blades and the ND filter by changing them.
JP 04-345149 A Japanese Patent Application Laid-Open No. 08-17997

However, in the so-called guillotine type in which the two blades of the conventional example of Patent Document 1 are moved in the opposite directions, the diaphragm blades are simply adopted by adopting a diaphragm having an ND filter attached to the diaphragm blades. In the middle of the process of reaching the small aperture, there is a problem that the through portion where the ND filter does not cover the entire surface of the aperture aperture produces an effect like a small aperture and the image quality deteriorates.
In addition, since the ND filter and the diaphragm blades start to move simultaneously from the aperture opening diameter, the light amount change with respect to the rotation angle of the drive actuator rotor (change in output of the Hall element) is significant at the F number near the aperture opening diameter, and the light amount adjustment control Will become difficult.

On the other hand, there are devices that mount diaphragm blades and drive actuators for ND filters, enable independent drive, and limit the amount of light to prevent a significant change in the amount of light near the aperture diameter. The problem of enlargement and cost increase occurs.
Further, even in the conventional example disclosed in Patent Document 2 in which the moving speeds of the aperture blade and the ND filter are changed, the aperture blade and the ND filter start to move simultaneously from the vicinity of the optical open diameter. It is not possible to expect so much effect on suppression.

  Accordingly, the present invention solves the above problems, prevents the MTF from being deteriorated due to small aperture diffraction, improves the controllability of the aperture, and reduces the space, and the light amount adjustment device. An object of the present invention is to provide an optical device (lens barrel) and a photographing device.

The present invention provides a light amount adjusting device configured as follows, an optical device (lens barrel) having the light amount adjusting device, and a photographing device.
That is, the light quantity adjusting device according to the present invention is configured to relatively align the diaphragm blades to adjust the light quantity by changing the size of the apertures by the relative movement of the diaphragm blades forming the opening and the relative movement of the diaphragm blades. In a light amount adjusting device, the diaphragm blade driving means for moving the ND filter, an ND filter that moves separately from the diaphragm blade, and an ND filter driving means for moving the ND filter to the opening,
A common actuator for driving the diaphragm blade driving means and the ND filter driving means is provided. The actuator first operates only the ND filter driving means, and the opening is covered by the ND filter. The diaphragm blade driving means is configured to operate so that the opening is changed from an open state to a closed state. As a result, the diaphragm starts operating after the ND filter is optically closed, so that it is possible to improve the degradation of MTF due to small aperture diffraction, and the ND filter starts operating the diaphragm blades from the optically closed state. The diaphragm and the ND filter do not operate simultaneously from the aperture opening diameter, and it is possible to suppress the change in the light amount with respect to the rotation angle (change in Hall element) of the actuator rotor.
Further, the light amount adjusting device of the present invention has a one-sided structure in which the ND filter driving means is provided directly connected to the actuator and is in contact with a one-sided part of the ND filter. The blade driving means is configured to be rotatable and is arranged coaxially with the diaphragm blade driving means, and is biased by a spring in a predetermined direction relative to the ND filter. This makes it possible to suppress changes in the amount of light in the vicinity of the aperture opening diameter compared to a type of diaphragm with an ND filter attached to the diaphragm blades, improving the diaphragm controllability and improving the degradation of MTF due to small diaphragm diffraction. In addition, it is not necessary to drive the ND filter with a separate actuator, and the space can be reduced.
Further, the ND filter driving means of the light quantity adjusting device of the present invention is configured to be able to continue the movement even after the movement of the ND filter is restricted at the stage where the ND filter covers the opening by the one-sided structure, The diaphragm blade is relatively moved in conjunction with the diaphragm blade driving means by continuing the movement. Accordingly, the diaphragm blade driving means can be driven by the common actuator depending on the ND filter driving means to which the generated force of the actuator is directly transmitted, and the space of the aperture unit can be reduced.
In the light amount adjusting apparatus of the present invention, the ND filter is an ND filter having a single density or two or more densities.
The optical device of the present invention is characterized by including an optical system having any one of the light amount adjusting devices described above.
In addition, a photographing apparatus according to the present invention is characterized by including a photographing optical system having any of the light amount adjusting apparatuses described above.

  According to the present invention, it is possible to prevent deterioration of the MTF due to small aperture diffraction, improve the controllability of the aperture, and reduce the space, and an optical device (lens mirror) having the light amount adjustment device. Tube) and an imaging device can be realized.

  The best mode for carrying out the present invention will be described by the following examples.

Embodiments in which the light amount adjusting device of the present invention is applied to a lens barrel will be described below with reference to the drawings.
FIG. 1 is a cross-sectional view showing a configuration example of a lens barrel having a four-group variable magnification optical system with convex and concave portions in an embodiment provided with a diaphragm device to which the light amount adjusting device of the present invention is applied.
Here, L1 is a first lens group, L2 is a second lens group that performs a zooming operation by moving in the optical axis direction, and L3 is a third lens that moves in a plane perpendicular to the optical axis and performs a camera shake correction operation. The lens group L4 is a fourth lens group that performs a focusing operation by moving in the optical axis direction.
2 to 4 are diagrams showing the configuration of the diaphragm device 9 of the present embodiment, which is fixed to the shift unit 3 with screws between the second lens group L2 and the third lens group L3 in FIG. 2 is an exploded perspective view of the diaphragm device 9, FIG. 3 is a front view of the diaphragm device 9, and FIG. 4 is a diagram continuously showing the movement of the diaphragm blades and the ND filter when the diaphragm is closed from the open state. is there.

Here, the specific configuration of the lens barrel will be described later. First, the diaphragm device 9 of this embodiment will be described.
2 and 3, reference numerals 95 and 96 denote diaphragm blades, and 97 denotes an ND filter. The diaphragm device 9 of the present embodiment moves the two diaphragm blades 95 and 96 around the optical axis in order to change the amount of incident light. It is configured as a so-called guillotine diaphragm that is moved to a position to change the aperture diameter.
Reference numeral 91 denotes a rotary electromagnetic actuator (motor), 94 denotes an ND drive lever, and the ND filter 97 is driven via the rotary electromagnetic actuator (motor) 91 and the ND drive lever 94.

94a is a protrusion provided on the ND drive lever 94, 97b is an ND filter one-sided contact part formed on the ND filter 97, and this protrusion 94a is joined to the ND filter one-sided part 97b in a one-sided state, The driving force of the ND driving lever 94 is transmitted to the ND filter 97. The protrusion 92a of the diaphragm base plate 92 is fitted into the ND filter rotation center hole 97a. As a result, the ND filter can reciprocate around the ND filter rotation center hole 97a.
Here, the ND filter 97 has a single concentration, but may be an ND filter having two or more types of concentrations in order to prevent small aperture diffraction. In addition, a transparent portion having a transmittance of 100% may exist in the two or more types of concentrations.
Reference numeral 93 denotes a seesaw-type diaphragm drive lever, and the diaphragm blades 95 and 96 are driven via the seesaw-type diaphragm drive lever 93. The aperture drive lever 93 is arranged coaxially with the ND drive lever 94 and is rotatable. The protrusion 93 a of the diaphragm drive lever 93 is fitted into the long hole 95 a of the diaphragm blade 95, and the protrusion 93 b of the drive lever 93 is fitted to the long hole 96 a of the diaphragm blade 96. Reference numeral 92 denotes a base plate (that is, a casing) of the diaphragm base plate, but two projections (not shown) of the lid member 99 of the diaphragm base plate are fitted into the long hole portions 95b and 96b of the two diaphragm blades, respectively. Accordingly, the diaphragm blades 95 and 96 are guided by the protrusions of the lid member 99 and reciprocate in the vertical direction as the diaphragm drive lever 93 rotates.

Reference numeral 98 denotes a mechanical spring. The diaphragm drive lever 93 and the ND filter 97 are always urged in the closing direction by the mechanical spring 98. The ND filter 97 is closed, and the diaphragm drive lever 93 is an ND drive lever. Is always urged by the mechanical spring 98 in the closing direction.
As the actuator 91, an electromagnetic drive actuator having a rotor made of a permanent magnet configured in a cylindrical shape (or a rotor magnetized on an outer peripheral surface of a metal body configured in a cylindrical shape) is used. The actuator is controlled in rotation position and rotation amount (rotation angle) by detecting the movement change of the magnetic poles on the outer peripheral surface of the rotor by a Hall element. Note that a stepping motor may be used in place of the electromagnetic drive actuator. In this case, if a mechanism for determining the initial position is provided, the aperture shape of the diaphragm is determined by the number of steps, so the Hall element is not necessary.

Here, when the actuator 91 is rotated, the opening / closing operation is performed in the order of 9 (a) to 9 (c) from the aperture opening to the closing as shown in FIG.
In this operation, only the ND filter 97 operates from 9 (a) to 9 (b). That is, the diaphragm drive lever 93 is restricted from rotating by a mechanical stopper (not shown) provided on the main plate 92. On the other hand, since the ND filter 97 is always urged in the closing direction by the mechanical spring 98, the ND filter 97 is always in the one-sided contact state with the projection part 94a of the ND drive lever 94. When the driving force of the ND drive lever 94 is transmitted to the ND filter 97, only the ND filter 97 operates.

  Next, only the diaphragm blades operate from 9 (b) to 9 (c). That is, when the ND filter 97 hits an ND filter stopper (not shown) provided on the ground plate 92, the rotational movement of the ND filter 97 is restricted. At this time, since the ND filter 97 and the ND drive lever 94 have a one-sided structure, the ND drive lever 94 can perform the rotational motion even after the ND filter 97 restricts the rotational motion. At the same time as the filter 97 is optically closed, the diaphragm drive lever 93 and the ND drive lever 94 are configured to start mechanical interlocking. As a result, the ND drive lever 94 is interlocked with the rotational movement of the diaphragm drive lever 93, and the diaphragm blades 95 and 96 start a straight movement.

According to the above operation sequence, the ND filter performs a single operation, and after closing the ND filter optical, the diaphragm blades start to operate, so that the aperture opening is not completely covered by the ND filter 97, so-called “ND half-hanging” state Is only when the optical is open, otherwise the ND filter 97 completely covers the aperture. This is shown in (a) to (f) in the driving sequence of the diaphragm device having the structure in which the ND filter is attached to the diaphragm blades shown in FIG. 6 in the conventional diaphragm device shown in the exploded perspective view of FIG. In contrast to the “ND half hook” driving state, the “ND half hook” in the vicinity of the small stop can be eliminated in this embodiment. In other words, in this embodiment, by adopting such a driving mechanism, it is possible to drive the diaphragm blades and the ND filter with one actuator, and to suppress the deterioration of the MTF due to the small diaphragm diffraction.
Further, in this embodiment, it is possible to avoid simultaneous driving of the aperture blade and the ND filter from the optical open position, and it is possible to suppress the change in the Hall element output with respect to the light amount change in the vicinity of the optical open. Can be facilitated. That is, in this embodiment, the aperture control can be facilitated for the aperture device having a structure in which the ND filter is attached to the aperture blade of the conventional example shown in FIG.
In this embodiment, the diaphragm blades 95 and 96 and the ND filter 97 can be driven by one actuator 91, and the diaphragm drive lever 93 and the ND drive lever 94 are coaxially arranged. It is not necessary to provide a motor for driving alone, and an extra space for disposing the ND drive lever can be eliminated, thereby making it possible to achieve compactness.

Specifically, the diaphragm device of the present embodiment can be configured as the lens barrel diaphragm device 9 shown in FIG. A specific configuration of the lens barrel will be described below. In FIG. 1, 1 is a front lens barrel unit that holds the first lens unit L1, 2 is a moving frame that holds the second lens unit L2, and 3 is a third lens unit L3 that moves in a plane perpendicular to the optical axis. A shift unit 4 enables a moving frame for holding the fourth lens unit L4, and 5 denotes a rear lens barrel to which an image pickup device such as a CCD is attached. Here, the two guide bars are positioned and fixed by the front lens barrel unit 1 and the rear lens barrel 5. In addition, a guide bar different from the guide bar is positioned and fixed by the shift unit 3 and the rear barrel 5.
The moving frame 2 is supported by two guide bars that are positioned and fixed by the front lens barrel unit 1 and the rear lens barrel 5 so as to be movable in the optical axis direction. The moving frame 4 is supported by a guide bar positioned and fixed by one of the two guide bars, the shift unit 3 and the rear barrel 5 so as to be movable in the optical axis direction. The shift unit 3 is positioned on the front lens barrel unit 1 and is sandwiched between the rear lens barrel 5 and the front lens barrel unit 1.

Here, 9 is a stop device that changes the amount of light incident on the optical system, and is configured as a so-called guillotine stop that changes the aperture diameter by moving two stop blades around the optical axis. Between L2 and the third lens unit L3, screws are fastened to the shift unit 3 with screws.
The rear lens barrel 5 is positioned on the front lens barrel unit 1 and, at the same time, is sandwiched between the shift unit 3 as described above, and is fastened together from behind by three screws.
Reference numeral 10 denotes a lead screw which is a driving means for moving the fourth lens unit L4 in the optical axis direction to perform a focusing operation. The lead screw has a bearing shape at the front and rear, and is magnetized with multiple poles at the rear. The rotor magnet 10a is fixed.

  Reference numeral 11 denotes a stepping motor stator unit for rotating the rotor magnet 10a, and the lead screw 10 is supported by a bearing unit provided in the shift unit 3 and the stepping motor stator unit 11. The lead screw 10 meshes with a rack 4a attached to the moving frame 4, and moves the fourth lens unit L4 by the rotation of the rotor magnet 10a. Further, the backlash of the moving frame 4, the guide bar, the rack 4a, and the lead screw 10 is offset by the torsion coil spring 4b.

A lead screw 12 is a driving means for moving the second lens unit L2 in the optical axis direction to perform a zooming operation. The lead screw has a bearing shape at the front and rear, and is magnetized with multiple poles at the rear. The rotor magnet 12a is fixed.
Reference numeral 13 denotes a stepping motor starter unit for rotating the rotor magnet 12a. The lead screw 12 is supported by a bearing portion provided in the shift unit 3 and the stepping motor starter unit 13. The lead screw 12 meshes with a rack 2a attached to the moving frame 2, and moves the second lens unit L2 by the rotation of the rotor magnet 12a. Further, the play of the moving frame 2, the guide bar, the rack 2 a, and the lead screw 12 is offset by the torsion coil spring 2 b. The stepping motor stator units 11 and 13 are each fixed to the rear barrel 5 with two screws.

A photo interrupter 14 is a focus for detecting the reference position of the fourth lens unit L4 by electrically detecting the switching between light shielding and light transmission due to movement of the light shielding portion formed in the moving frame 4 in the optical axis direction. A reset switch, which is fixed to the rear barrel 5 with a single screw through the substrate.
A photo interrupter 15 is a zoom for detecting the reference position of the second lens unit L2 by electrically detecting the switching between light shielding and light transmission due to movement of the light shielding part formed in the moving frame 2 in the optical axis direction. It is a reset switch and is fixed to the front lens barrel unit 1 with one screw through the substrate.

Here, an example of the configuration of the shift unit 3 will be described in detail. A configuration of the shift unit 3 that allows the third lens unit L3 to move within a plane perpendicular to the optical axis will be described. The third lens unit L3 has a vertical direction for correcting image blur in the PITCH direction (camera vertical angle change) and a horizontal direction for correcting image blur in the YAW direction (camera horizontal angle change). In order to change, each of the vertical direction and the horizontal direction is independently driven and controlled by dedicated drive means and position detection means, and is positioned at an arbitrary position around the optical axis.
Since the vertical and horizontal drive means and the position detection means have the same configuration at an angle of 90 degrees, only the vertical direction (represented in the cross-sectional view of FIG. 2) will be described.
Reference numeral 3b denotes a shift base that is a fixing member that is integrated with the lens barrel and serves as a base for a fixed portion of the shift unit. Reference numeral 3d denotes a compression coil spring that is an urging means, which will be described later. For example, a phosphor bronze wire is suitable so that the magnet is not attracted to the detection and drive magnets.
Reference numeral 3a denotes a shift barrel that is a movable member that holds a third lens group L3 that is a shifting lens group. In the shift barrel 3a, the front end of the compression coil spring 3d is connected to the optical axis of the third lens group L3. The coil is fitted substantially coaxially, and one end of the coil is fitted and fixed in a V-shaped groove (not shown) provided in the shift barrel 3a.

  3l is a ball sandwiched between the shift base 3b and the shift lens barrel 3a. Although only one ball is shown in the figure, three balls are arranged in a plane perpendicular to the optical axis direction. For example, SUS304 (austenitic stainless steel) is suitable for the material so as not to be attracted by a driving magnet, which will be described later, disposed in the vicinity. The surfaces with which the ball 3l is in contact are the shift base side and three locations, and the shift lens barrel side and three locations, and each of the three contact surfaces is a surface perpendicular to the optical axis of the optical system. When the nominal diameters of the three balls are the same, the holding and moving guidance can be performed while keeping the shift lens group L3 at a right angle to the optical axis by suppressing the difference between the positions of the three surfaces in the optical axis direction. It becomes possible. Reference numeral 3c denotes a sensor base which is a fixing member on the rear side. The position is determined by two positioning pins and is coupled to the shift base 3b by three screws. The rear end of the compression coil spring 3d is fitted to the sensor base 3c substantially coaxially with the optical axis of the lens barrel. The compression coil spring 3d is compressed between the shift lens barrel 3a and the sensor base 3c, and urges the shift lens barrel 3a including three balls including the ball 3l to the shift base 3b.

  Further, the viscosity is such that the balls do not easily fall off the contact surfaces even when the three balls including the balls 3l are not sandwiched between the shift base 3b and the shift lens barrel 3a between the three contact surfaces. By applying the lubricant having the above, it is possible to prevent the position of the ball from easily deviating even if the inertial force exceeding the urging force of the compression coil spring 3d is applied to the shift barrel 3a and the ball is not clamped. .

Next, driving means for the shift barrel 3a will be described.
3j is a driving magnet magnetized in two radial directions with respect to the optical axis, 3k is a yoke for closing the magnetic flux on the front side of the driving magnet 3j in the optical axis direction, and 3i is fixed to the shift barrel 3a by bonding. The coil 3h is a yoke for closing the magnetic flux on the rear side in the optical axis direction of the driving magnet 3j. The driving magnet 3j is a magnet for the shift base 3b so as to form a space in which the coil 3i moves. The magnetic circuit is fixed by the magnetic force. When a current is passed through the coil, a Lorentz force is generated in the direction substantially perpendicular to the magnetization boundary of the two-pole magnetization of the driving magnet 3j due to the repulsion between the magnetic lines generated in the magnet and the coil. Move. This is a so-called moving coil type driving means. Since the said structure is arrange | positioned in the vertical and horizontal direction, a movable member can be driven to two directions substantially orthogonal. At this time, as described above, the shift barrel 3a is urged while holding the three balls with respect to the shift base 3b by the compression coil spring 3d, and therefore becomes a load when the shift barrel 3a is driven. The friction force is only rolling friction of the ball. Since the frictional force is extremely small, the shift driving unit 3a can be finely controlled.

Next, the position detection means of the shift barrel 3a will be described.
3f is a detection magnet magnetized in two radial directions with respect to the optical axis, 3g is a yoke for closing the magnetic flux on the front side of the detection magnet 3f in the optical axis direction, and both are fixed to the shift barrel 3a. Has been. Reference numeral 3e denotes a Hall element that converts the magnetic flux density into an electric signal, and is positioned and fixed to the sensor base 3c. The position detection means is constituted by the above configuration. When the shift barrel 3a is driven in the vertical or horizontal direction, the magnetic flux density detected by the Hall element 3e changes, and the third magnetic flux density is detected as an electrical signal from the Hall element by appropriate signal processing. It becomes possible to detect the position of the lens unit L3.

  As described above, the configuration example in which the aperture device to which the light amount adjusting device of the present invention is applied is used for the lens barrel has been described. Even if it is applied, the MTF deterioration at the time of small aperture can be prevented or the aperture can be easily controlled as in the case of the above embodiment, and the space can be reduced.

Sectional drawing which shows the structural example of the lens barrel in the Example provided with the aperture device to which the light quantity adjustment apparatus of this invention is applied. 1 is an exploded perspective view of a diaphragm device in an embodiment of the present invention. The front view of the aperture_diaphragm | restriction apparatus in the Example of this invention. The figure which showed continuously the operation | movement of the aperture blade and ND filter at the time of closing the aperture_diaphragm | restriction in the Example of this invention. The disassembled perspective view of the diaphragm | throttle device in a prior art example. The figure which showed continuously the operation | movement of the aperture blade and the ND filter at the time of closing the aperture stop in the aperture device of a prior art example from open.

Explanation of symbols

1: Front lens barrel unit 2: Moving frame 3: Shift unit 4: Moving frame 5: Rear lens barrel 9: Aperture device L1: First lens unit L2: Second lens unit L3: Third lens unit L4: Fourth Lens group 91: Actuator
92a: Ground plate projection 93: Diaphragm drive lever 94: ND drive lever 94a: ND drive lever projection 95, 96: Diaphragm blade 97: ND filter 97a: ND filter rotation center hole 97b: ND filter single contact portion 98: Mechanical spring

Claims (6)

A plurality of aperture blades forming an aperture, and aperture blade drive means for relatively moving the aperture blades to change the size of the aperture and adjust the amount of light by relative movement of the aperture blades;
In a light amount adjusting device having an ND filter that moves separately from the diaphragm blades, and an ND filter driving means that moves the ND filter to the opening,
A common actuator for driving the diaphragm blade driving means and the ND filter driving means is provided. The actuator first operates only the ND filter driving means, and the opening is covered by the ND filter. A light quantity adjusting device having a configuration in which the aperture blade driving means is operated so that the opening is changed from an open state to a closed state.   The ND filter driving means is provided directly connected to the actuator, and has a one-sided structure in which the ND filter driving means is in contact with a one-sided portion of the ND filter, while the diaphragm blade driving means is configured to be rotatable. The light quantity adjusting device according to claim 1, wherein the light quantity adjusting device is arranged coaxially with the diaphragm blade driving means and is biased by a spring in a predetermined direction relative to the ND filter.   The ND filter driving means is configured to be able to continue the movement even after the movement of the ND filter is restricted at the stage where the ND filter covers the opening by the one-sided structure, and the diaphragm blade driving means by the continued movement. The light quantity adjusting device according to claim 2, wherein the diaphragm blades are moved relative to each other.   The light quantity adjusting device according to any one of claims 1 to 3, wherein the ND filter is an ND filter having a single density or two or more densities.   An optical device comprising an optical system having the light amount adjusting device according to claim 1.   A photographing apparatus comprising a photographing optical system having the light amount adjusting device according to any one of claims 1 to 4.

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