JPH11149030A - Lens driving device and lens barrel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To inexpensively provide a lens driving device which copes with even a different lens barrel by the same coil, magnet and yoke, is shared, highly accurately drives a moving lens at high speed and by which a lens barrel is miniaturized by a simple constitution. SOLUTION: One magnetic circuit is provided at the lens barrel and a coil 8 moving a moving lens group in an optical axis direction is provided at a position separated from the moving lens group of a lens holding means, so that they are integrally constituted with the lens holding means. Also, a driving means and a position detecting means are arranged in the vicinity of the sleeve 9 of the lens holding means by seeing from the optical axis direction, and the position of the center of gravity of a lens driving body is arranged in the vicinity of the driving means. Also, the driving source of a variator lens driving means and a diaphragm driving controlling part 25 are provided in a direction orthogonal with the magnetization direction of a magnet by seeing from the optical axis direction, and are constituted so as to be opposed to each other by holding an optical axis, so that they are attached to the lens barrel.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lens driving device and a lens barrel for driving a photographing lens in an image pickup device such as a video camera.

[0002]

2. Description of the Related Art In recent years, the technology of video cameras has been remarkably advanced, and many performance improvements have been made in various fields such as digital recording, miniaturization, lightening, long shooting, high speed, and high magnification zoom.

In a lens barrel serving as an image pickup unit, a so-called “inner focus method” in which focus adjustment is performed by changing the position of a focus lens group behind the zoom lens group in the optical axis direction is downsized. Since it is advantageous in terms of weight reduction, it is widely used at present, and because of the characteristic that the focal plane moves according to the zoom magnification, the focus lens group is generally based on the movement trajectory data for each subject distance stored in the microcomputer. Move in the direction of the optical axis in accordance with a change in the position of the zoom lens group, and form an object image on the imaging surface of the image sensor at the rear of the lens barrel.

In view of the characteristic of the movement trajectory data that the amount of movement of the focus surface on the telephoto side is large, to move the focus lens group so as to follow the zoom lens group, the focus is closer to the telephoto side than the zoom lens group. It is necessary to move the lens group quickly, and among the above items of performance improvement,
In order to realize high-speed zooming and long-time shooting, the driving part of this focus lens group is excellent in high-speed response and low power consumption that can follow the position change of the zoom lens group instead of the conventional stepping motor. A voice coil type linear actuator is employed.

As examples using this linear actuator, Japanese Patent Application Laid-Open Nos. 9-61692 and 9-12 are disclosed.
In the lens barrel described in Japanese Patent No. 7397, a rod magnet composed of a rod-shaped magnetic body and a magnet both ends of which are supported in the optical axis direction by a yoke, and a movable coil wound on a bobbin sliding along the rod magnet A lens driving device including the bobbin and a connecting means for holding a movable lens and connecting a movable lens holder along a guide means has been devised.

As another example, Japanese Patent Application Laid-Open No. H8-2482
In the lens barrel described in Japanese Patent Publication No. 90, a voice coil is provided around a lens holder that holds a focus lens and is slidable in the optical axis direction along a guide axis, and lenses on both sides of the voice coil. Focus lens driving means has been devised which includes a pair of yokes arranged on the lens barrel side and a pair of magnetic circuits composed of magnets joined and fixed to these yokes.

[0007]

However, in a lens barrel using a lens driving device described in JP-A-9-61692 and JP-A-9-127397, a linear actuator is provided separately from the lens barrel. Because it can be configured, the same linear actuator can be used even with lens barrels with different zoom magnifications and optical performances.In other words, there is an advantage that the components of the driving means can be shared, but the linear actuator and the lens holder are connected by a connecting member. Due to the coupling, there is a problem that mechanical backlash occurs and the lens holder cannot be driven at a high speed, and a space for a connecting member is required in the lens barrel, and thus the lens barrel cannot be downsized.

In the lens barrel described in Japanese Patent Application Laid-Open No. 8-248290, a voice coil is directly mounted around a lens holder, so that a lens drive described in Japanese Patent Application Laid-Open Nos. 9-61692 and 9-127397 is used. Although there is no backlash which is a problem of the device, the lens holder can be driven at high speed, but if the size of the focus lens changes, the size of the voice coil needs to be changed. There is a problem that it is necessary to provide linear actuators corresponding to different lens barrels, that is, it is not possible to share parts of the driving means.
Furthermore, since it is necessary to provide a sleeve fitted on the guide shaft outside the voice coil and a magnetic scale opposed to a magnetic sensor provided on the lens barrel which is a means for detecting the position of the lens holder, the lens barrel has a small size. There was also a disadvantage that it was difficult to achieve the formation.

SUMMARY OF THE INVENTION In view of the above problems, an object of the present invention is to provide a small-sized drive component that can be used in common, can cope with different types of lens barrels, and can drive a lens holder holding a moving lens at high speed and with high accuracy. An objective is to provide a lens barrel with a simple configuration at a low cost.

[0010]

In order to solve this problem, a lens driving device according to the present invention comprises a first guiding means for guiding a moving lens group in an optical axis direction, and a moving lens group. And a lens holding means provided with a first sleeve that fits with the first guide means, and provided on each of the lens barrel and the lens holding means for moving the lens holding means. It has one functioning driving means and position detecting means provided and functioning so as to be opposed to the lens barrel and the lens holding means, respectively, for detecting the position of the moving lens group.

Further, in the lens driving device according to the present invention, as the driving means, one magnetic circuit comprising a magnet and a yoke magnetized perpendicular to the optical axis direction is provided in the lens barrel, By passing a current perpendicular to the magnetic flux generated by the magnet, the coil that moves the lens holding means in the driving direction is moved away from the moving lens group of the lens holding means. And a feature that is integrated with the lens holding means.

Further, in the lens driving device according to the present invention, as the driving means, the lens holding means includes one magnetic circuit including at least a magnet magnetized perpendicular to the optical axis direction. The lens holding means is provided at a position distant from the lens holding means, is formed integrally with the lens holding means, has a predetermined gap with the magnet, and is supplied with an electric current so as to be orthogonal to the magnetic flux generated by the magnet. It has a configuration in which a coil movable in the driving direction is provided in the lens barrel.

Further, in the lens driving device according to the present invention, the driving means and the position detecting means are arranged near the first sleeve of the lens holding means when viewed from the optical axis direction, and the moving lens group is provided. And the lens holding means;
The apparatus has a configuration in which the position of the center of gravity of the lens driving body constituted by the driving means and the position detecting means is arranged near the driving means or the position detecting means.

Further, the lens barrel of the present invention has, as the driving means, a magnetic circuit composed of the magnet and the yoke magnetized perpendicularly to the optical axis direction, and a predetermined gap between the magnet and the magnet. A focus lens comprising: a coil for moving the lens holding means in a driving direction by applying a current so as to be orthogonal to a magnetic flux generated by a magnet; and a magnetic sensor and a magnetic scale as the position detecting means. A driving device, second guide means for guiding movement of the variator lens group in the optical axis direction,
A variator lens holding means for holding the variator lens group and having a second sleeve fitted with the second guide means; a drive source for moving the variator lens holding means; and the variator lens holding means A variator lens moving means for moving the variator lens holding means in the optical axis direction by the driving source; a variator lens driving means attached to the lens barrel; And a drive control unit that drives the diaphragm unit body, and the entire lens barrel composed of a diaphragm unit attached to the lens barrel, as viewed from the optical axis direction. The drive source of the variator lens drive unit and the drive of the diaphragm unit in a direction orthogonal to the magnetization direction of the magnet. Is arranged to the control unit are relatively across the optical axis, and it has the characteristics attached to the lens barrel.

Further, the lens driving device according to the present invention has a configuration in which, when viewed from the optical axis direction, the position of the center of gravity of the lens driving member is provided outside two sides of the coil facing the magnetizing direction of the magnet. Have

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of a lens driving device and a lens barrel according to the present invention will be described below with reference to the drawings.

FIG. 1 is a longitudinal sectional view showing a front side of a rear section of a lens barrel according to an embodiment of the present invention, and FIG. 2 is a rear view of the lens barrel according to the embodiment of the present invention. FIG. 3 is a cross-sectional view of a main part showing an internal configuration of a lens barrel according to an embodiment of the present invention. FIG. 4 is a longitudinal sectional view of a main part showing an internal configuration of the lens barrel according to the embodiment of the present invention.
FIG. 5 is an internal perspective view of a focus lens driving portion of the lens barrel according to the embodiment of the present invention, and FIG. 6 is a diagram showing a flow of magnetic flux of a magnetic circuit of the focus driving portion of the lens barrel according to the embodiment of the present invention. It is.

The lens barrel according to the embodiment of the present invention includes an electric zoom mechanism for changing magnification, an automatic aperture device for reproducing a subject with an appropriate exposure, and an autofocus mechanism for automatically focusing on the subject. A lens barrel for a general video camera of the inner focus type provided. Therefore, this lens barrel is composed of two fixed lens groups, one fixed lens group on the subject side and the third fixed lens group in the lens barrel, a variator lens group for zooming and the like, and a focus lens group for focus adjustment. It is composed of two moving lens groups and a diaphragm device.

First, a lens barrel according to an embodiment of the present invention will be described with reference to FIGS.

3 and 4, reference numeral 3a denotes a front portion of the lens barrel, 3b denotes a rear portion of the lens barrel, and 23 denotes a lens barrel 3.
a, a first fixed lens group fixed to the subject side, 22 a variator lens group for zooming or the like, 2 a focus lens group for focus adjustment, and 27 a variator lens group 3 and a focus lens group 4 And the lens barrel 3a
A third lens group fixed between the lens groups 3 and 3b, 24 is a diaphragm main body provided in front of the third lens group fixed lens group 27, 30
Is a solid-state imaging device such as a CCD, 31 is a CCD mounting plate for mounting the solid-state imaging device 30 to the rear of the lens barrel 3b, 29 is an optical filter which is placed in front of the solid-state imaging device 30 and is made of quartz or the like. It is.

A variator lens group 22 and a focus lens group 2 are held by a variator lens holder 21 and a focus lens holder 1, respectively, are arranged parallel to the optical axis, and are fixed at both ends to lens barrels 3a and 3b. It is configured to be independently slidable along the optical axis along each of 4a and 4b.

Since the variator lens group 22 must move in a wide range from the telephoto end to the wide-angle side in conjunction with the focus lens, controllability is required as a drive source for driving the variator lens holder 21. A stepping motor which has a high function as an encoder by counting the number of input pulses is generally used as the zoom motor 15.

The variator lens driving means is formed on a zoom motor 15 as a driving source, a bracket 16 to which the zoom motor 15 is assembled, and an output shaft of the zoom motor 15, and is rotatably supported on the bracket 16 and A feed screw 18 having a length dimension of a moving range of the variator lens, and a rack 19 which engages with the feed screw and converts a rotary motion into a linear motion;
The zoom motor 15 is fixed to the lens barrel 3 a via a bracket 16, and the rack 19 is fixed to a variator lens holder 21. Therefore, with this configuration, the variator lens holder 21 can be arbitrarily moved according to the number of steps of the zoom motor 15.

For detecting the reference position of the variator lens 22, a photo-interrupter 28 composed of a light-emitting element (not shown) such as an LED and a light-receiving element (not shown) such as a phototransistor passes between them and blocks light. A variance holder 21 is provided with a position detecting piece (not shown) integrally formed. When the power is turned on, the variator lens group 22 is moved to the photointerrupter 28, and this position is set as a reference position. Is calculated as the number of steps of the zoom motor 15.

The aperture unit extracts an average value or a peak value of a video signal output in order to reproduce a subject with an appropriate exposure, and a plurality of aperture blades (not shown) so as to obtain an appropriate exposure. A diaphragm main body portion 24, which is constituted by a so-called auto iris that automatically adjusts the optical aperture of the lens barrel by driving the lens barrel, and stores a plurality of diaphragm blades (not shown);
An arc tutor (not shown) for driving the plurality of aperture blades (not shown) and an aperture drive control unit 25 incorporating a control unit (not shown) are provided.

Since the diaphragm main body 24 needs to accommodate a plurality of diaphragm blades (not shown) even in the case of the maximum optical aperture, it has an outer dimension almost equal to the outermost dimension of the lens barrel 3a. When the aperture unit is attached to the lens barrel 3a, the aperture drive control unit 25 projects. Therefore, the size of the lens barrel is determined by the aperture unit.

Next, the focus lens driving means of the lens barrel according to the embodiment of the present invention will be described with reference to FIGS.

In FIGS. 1 and 5, a focus lens holder 1 holds a focus lens group 2 and is arranged parallel to the optical axis, and both ends are fitted with a guide shaft 4a fixed to lens barrels 3a and 3b. The guide shaft 4 is provided with a sleeve 9 to be
It is configured to be slidable in the optical axis direction along a and 4b. In order to drive the lens holder 1 in the direction of the optical axis, a magnetic circuit composed of a magnet 5 magnetized perpendicular to the driving direction, a U-shaped main yoke 6 and a plate-shaped side yoke 7 is a lens. A coil 9 is provided in the focus lens holder 1 at a position slightly away from the focus lens group 2, and is provided in the lens barrel 3 b.
Is fixed so as to have a predetermined gap, and a current flows through the coil 9 so as to be orthogonal to the magnetic flux generated by the magnet 5, whereby the focus lens holder 1 is driven in the optical axis direction.

As a means for detecting the position of the focus lens holder 1, a magnetic sensor 1 is provided on the lens barrel 3b.
Reference numeral 0 denotes a magnetic scale in which a ferromagnetic material such as ferrite is moved at a constant speed with respect to a magnetic head in a focus lens holder 1 so that S poles and N poles are alternately magnetized at a predetermined pitch along a driving direction. 11 is attached so as to face the detection surface of the magnetic sensor 10 at a predetermined distance. The magnetic sensor 10 is composed of an MR element (not shown) made of a ferromagnetic thin film such as NiFe or NiCo having a characteristic of changing a resistance value by a magnetic field.
This MR element (not shown) is a phase type magnetoresistive sensor.
Are provided in the driving direction at an interval of 1/4 of the magnetization pitch between the S pole and the N pole of the magnetic scale 11.

When the focus lens holder 1 moves and the position of the magnetic scale 11 with respect to the magnetic sensor 10 changes, the resistance value of the MR element (not shown) changes in response to the change in the magnetic field intensity. The output signal of the voltage applied to the input signal (not shown) has two sinusoidal waveforms having phases different from each other by 90 °, and the two signal waveforms are subjected to modulation interpolation processing by a signal processing circuit (not shown) to obtain a focus. The position and the driving direction of the lens holder 1 are detected, and the focus lens group 2 is moved by the control circuit (not shown) based on the movement trajectory data for each subject distance stored in the microcomputer (not shown) in advance. By moving in the optical axis direction according to the change in the position of the group 22, an object image is formed on the image forming plane of the image sensor 30 provided at the rear of the lens barrel 3b.

When viewed from the optical axis direction, the coil 8 is disposed near the sleeve 9 fitted with the guide shaft 4a. The magnetic scale 11 is also a magnetic sensor in which the magnetic sensor 10 is composed of the magnet 5 and the yoke 6. The coil 8, the sleeve 9, the magnetic scale 11, and the magnetic sensor 11 are arranged in a position opposite to the magnetic circuit and closest to the sleeve 9 so as to be hardly affected by magnetic flux leakage from the circuit. 10 are arranged in a straight line.

The center of gravity 14 of the focus lens driving body composed of the focus lens group 2, the focus lens holder 1, the coil 8 and the magnetic scale 11 is arranged near the coil 8. Therefore, the drive center point 12 at the center of the gap 32 of the coil 8 and the position detection point 13 on the magnetic scale 11 opposed to the magnetic sensor 10 are located near the sleeve 9 supporting the focus lens holder 1 and the center of gravity 14 Are also located near the drive center point 12, and the center of gravity 14 of the lens driver and the sleeve 9
Is provided outside the space between two opposing sides of the coil 8 in the magnetization direction of the magnet 5.

Therefore, when viewed from the optical axis direction, the magnet 5
The magnetic circuit including the focus lens group 2, the coil 8, the magnet 5, the main yoke 6, and the side yoke 7 is arranged in a direction orthogonal to the magnetization direction of the lens barrel 3b.
In the height direction becomes larger. Therefore, the aperture drive control unit 25 of the aperture unit is arranged in a direction orthogonal to the magnetization direction of the magnet 5 and in an empty space in front of the focus lens driving means on the subject side so that the aperture main body 24 does not interfere with the guide shafts 4a and 4b. And the guide shaft 4 is swung at an angle to the vertical direction of the lens barrel.
a, 4b. Further, the zoom motor 15 serving as a variator lens driving unit is moved to the stop main body 24.
And the bracket 16 is located at a position opposite to the diaphragm drive control unit 25 with the optical axis interposed therebetween so as not to interfere with the lens barrel 3.
a.

The effects of the lens driving device and the lens barrel according to the embodiment of the present invention described above will be described.

First, in the focus lens driving means,
By forming the movable coil 8 integrally with the focus lens holder 1 at a position distant from the focus lens group 2, there is no need to provide a connecting means between the driving means and the lens holding means, and high-speed driving is possible. In addition, downsizing can be achieved. In addition, since the magnetic circuit including the coil 8 and the magnet 5, the main yoke 6, and the side yoke 7 is not restricted by the size of the focus lens group 2,
Even for lens barrels with different zoom magnification and optical performance,
Since the same coil and magnetic circuit can be used, the driving member can be shared. Further, a connecting member or the like is not required, which is advantageous in reducing the number of parts and cost.

Further, since the focus lens holder 1 is configured to be slidable along the guide shafts 4a and 4b, there is a minute gap in the fitting portion between the sleeve 9 and the guide shaft 4a, Holder 1
Has some play with respect to the guide shaft 4a. When a current is applied to the coil 8 to drive the focus lens group 2 and a rotational moment is generated, the focus lens holder 1 slides in the optical axis direction while slightly rotating. As a result, the relative position between the drive center point 12 of the coil 8 and the position detection point 13 on the magnetic scale slightly changes.
In other words, a phase shift occurs between the drive center point 12 and the position detection point 13, and as a result, control responsiveness is deteriorated. In severe cases, an oscillation state is caused. .

Further, there is a problem that a lens deviation occurs due to the rotation behavior of the focus lens holder 1. On the other hand, in the embodiment of the present invention, the coil 8
The drive center point 12 and the position detection point 13 on the magnetic scale 11 are located near the sleeve 9, and the center of gravity 14 is also located near the drive center point 12.
Since the distance between the drive center point 12 with respect to the sleeve 9 and the center of gravity 14 is small, when the focus lens group 2 is driven,
At startup and during driving, a rotational moment hardly occurs.

Even if the rotation behavior occurs, the control error is minimized because the distance between the drive center point 12 and the position detection point 13 to the sleeve 9 is small. Therefore, control responsiveness is improved, and highly accurate drive control can be achieved.

In the embodiment of the present invention, a voice coil type linear actuator is applied to the focus lens driving means. However, the present invention is not limited to this, and an ultrasonic motor, a stepping motor or the like may be used as the driving means. Therefore, the same effect as described above can be obtained in the focus lens driving means having a configuration in which the position detecting means is provided in the focus lens holder 1 and the lens barrel 3b.

In the embodiment of the present invention, the fixed lens barrel 3b is provided with a magnetic circuit including the magnet 5, the main yoke 6 and the side yoke 7, and the focus lens holder 1 is provided with the coil 8 integrally. Although the configuration is adopted, conversely, even if the magnet 5 is joined and fixed to the focus lens holder 1 and the coil 8 is arranged in the lens barrel 3b, the effects of the present invention are not hindered at all.

The focus lens group 2 and its driving means are arranged in a direction orthogonal to the magnetization direction of the magnet 5 when viewed from the optical axis direction, and the size of the lens barrel 3b is increased. Is disposed in an empty space in the direction perpendicular to the magnetization direction of the magnet 5 and in front of the focus lens driving means, the diaphragm main body 24 is obliquely swung, and disposed inside the guide shafts 4a and 4b, and the zoom motor 15 is arranged at a position opposite to the diaphragm drive control unit 25 with the optical axis interposed therebetween, so that the longitudinal direction of the constituent members is aligned in the direction in which the size of the lens barrel becomes larger, so that the space of the entire lens barrel is Efficiency can be improved and downsizing can be realized.

As shown in FIG. 6, the leakage magnetic flux from the magnet 5 slightly acts on the three sides of the coil outside the gap 32 to generate a force in the direction opposite to the driving direction. Coil 8 with 5 magnetization directions
When there is a fulcrum inside the, a rotational moment is generated around the fulcrum in the driving direction. In the embodiment of the present invention, when viewed from the optical axis direction, the center of gravity 14 of the lens driver and the sleeve 9 are provided outside the two sides of the coil 8 in the magnetization direction of the magnet 5. As a result, the moment force generated by the force acting in the direction opposite to the driving direction is canceled, and the rotation behavior of the focus lens holder 1 is less likely to occur.

In the embodiment of the present invention, the magnetic sensor 10 is provided on the fixed lens barrel 3b and the magnetic scale 11 is provided on the movable focus lens holder 1. On the contrary, the fixed lens barrel 3 is provided. Even when the magnetic scale 11 is provided on the movable lens holder 3b and the magnetic sensor 10 is provided on the movable lens holder 1, the same effect as described above can be obtained.

Further, in the present embodiment, the magnetoresistive magnetic sensor 10 equipped with the MR element is used. However, other magnetic sensors such as a Hall element, and an optical LED
Or a combination of an optical sensor comprising a light emitting element such as a phototransistor and a light receiving element such as a phototransistor, and an optical scale in which light transmitting portions and light shielding portions are alternately formed at a fine pitch, or i
Use of any type of position detection sensor, such as a combination of a light emitting element such as an RED and a photoelectric conversion element such as a PSD, does not hinder the effects of the present invention.

Further, in the embodiment of the present invention, the lens barrel is provided with an auto-focus mechanism mounted on a video camera for automatically performing focusing on a subject and an electric zoom mechanism for changing a magnification. The invention is not limited to such a lens barrel for a video camera,
The movable lens structure is movably supported in the lens barrel by the guide means, and is also applicable to various lens barrels having lens driving means for moving the movable lens structure, such as a lens barrel for a still camera. can do.

[0046]

As described above, the lens driving device of the present invention functions by providing the driving means for moving the lens holding means provided with the position detecting means in the lens barrel and the lens holding means, respectively. The use of two driving means eliminates the need for connecting means for transmitting driving force from the driving means to the lens holding means, and enables a small-sized lens barrel capable of high-speed driving without mechanical play with a reduced number of parts. It can be realized at a low cost with a simple configuration.

Also, one magnetic circuit comprising a magnet and a yoke is provided in the lens barrel, and a coil for moving the moving lens group in the optical axis direction is provided at a position distant from the moving lens group of the lens holding means. By integrating it with the means, it is possible to respond to lens barrels with different zoom magnification and optical performance with the same coil, magnet and yoke, so it can be easily driven without impairing high speed driving performance The means can be shared.

Here, as a driving means, a lens holding means is provided integrally with at least one magnetic circuit including at least a magnet, and a coil for moving the lens holding means in the driving direction is arranged on the lens barrel side in the same manner as described above. The effect of can be raised.

The driving means and the position detecting means are arranged near the sleeve of the lens holding means when viewed from the optical axis direction, and the center of gravity of the lens driving body is arranged near the driving means. Since the distance to the drive center point with respect to the point is small, when driving the focus lens group, it is difficult for a rotational moment to occur during startup or during driving, and even if rotational behavior occurs,
Because the distance from the drive point and the position detection point to the bearing is small,
Control errors are minimized, and a lens barrel having excellent control response can be realized at a low cost with a simple configuration.

Also, a focus lens driving device including a magnetic circuit and a coil comprising a magnet and a yoke magnetized perpendicular to the optical axis direction as driving means and a magnetic sensor and a magnetic scale as position detecting means. A lens source comprising: a driving source for moving the variator lens holding unit; a variator lens driving unit including the driving unit; and a diaphragm unit including a diaphragm unit main body and a drive control unit driving the diaphragm unit main body. A driving source for a variator lens driving unit and a driving control unit for a diaphragm unit are provided in the cylinder in a direction orthogonal to the magnetization direction of the magnet when viewed from the optical axis direction, and a driving source for the variator lens driving unit and a diaphragm unit; By configuring the drive control units to face each other across the optical axis, the size of the lens barrel increases. By aligning the longitudinal direction of the forming member,
Space efficiency can be improved, and a small lens barrel with little unevenness can be realized.

By providing the position of the center of gravity of the lens driver or the sleeve outside the coil on the two sides facing the magnetization direction of the magnet when viewed in the optical axis direction, Cancel the moment force generated by the force acting in the opposite direction to the driving direction,
The effect of making the rotation hard to occur can be obtained.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a front side of a rear barrel portion of a lens barrel according to an embodiment of the present invention.

FIG. 2 is a rear view of the lens barrel.

FIG. 3 is a cross-sectional view of a main part showing an internal configuration of the lens barrel.

FIG. 4 is a longitudinal sectional view of a main part showing an internal configuration of the lens barrel.

FIG. 5 is an internal perspective view of a focus lens driving portion of the lens barrel.

FIG. 6 is a diagram showing a flow of a magnetic flux of a magnetic circuit of a focus driving portion of the lens barrel.

[Explanation of symbols]

 1 Focus Lens Holder 2 Focus Lens Group 3a, 3b Lens Barrel 4a, 4b Guide Shaft 5 Magnet 6 Main Yoke 7 Side Yoke 8 --- Coil 9 --- Sleeve 10 --- Magnetic sensor 11 --- Magnetic scale 12 --- Drive center point 13 --- Position detection point 14 --- Center of gravity 15 --- Zoom motor 16 ---- Zoom motor bracket 24--Aperture main body 25 ---- Aperture drive controller

Claims (10)

[Claims] A first guide means for guiding movement of the movable lens group in the direction of the optical axis; and a first sleeve for holding the movable lens group and fitting with the first guide means. A lens holding means for moving the lens holding means, the lens holding means being provided in each of the lens barrel and the lens holding means.
A lens driving device, comprising: one driving unit; and a position detecting unit provided to function relative to each of the lens barrel and the lens holding unit to detect the position of the moving lens group. . 2. A magnetic circuit comprising a magnet and a yoke magnetized perpendicularly to an optical axis direction is provided in said lens barrel as said driving means, said magnet having a predetermined gap with said magnet. By passing a current perpendicular to the magnetic flux generated by the magnet, a coil that moves the lens holding unit in the driving direction is provided at a position away from the moving lens group of the lens holding unit, and the lens holding unit and The lens driving device according to claim 1, wherein the lens driving device is integrally formed. 3. As the driving means, one magnetic circuit including at least a magnet magnetized perpendicular to the optical axis direction is provided in the lens holding means at a position away from the moving lens group of the lens holding means. A coil configured to be integral with the lens holding means, having a predetermined gap with the magnet, and passing a current perpendicular to the magnetic flux generated by the magnet, thereby moving the lens holding means in the driving direction. 2. The lens driving device according to claim 1, wherein the lens driving device is provided in the lens barrel. 4. The moving lens group, wherein the driving means and the position detecting means are arranged near the first sleeve of the lens holding means when viewed from the optical axis direction. 4. The apparatus according to claim 2, wherein a center of gravity of a lens driving body including the lens holding unit, the driving unit, and the position detecting unit is arranged near the driving unit. Lens drive. 5. A magnetic sensor provided on the lens barrel and a magnetic scale provided on the lens holding means as the position detecting means, or the magnetic scale provided on the lens barrel and the magnetic sensor provided on the lens holding means. The lens driving device according to claim 4, wherein the lens driving device is provided. 6. The focus lens driving device according to claim 5, wherein said movable lens group is a focus lens group. 7. A second guide means for guiding movement of the variator lens group in the optical axis direction, and a second sleeve which holds the variator lens group and is fitted with the second guide means. A variator lens holding means, a driving source for moving the variator lens holding means, and a variator lens moving means coupled to the variator lens holding means and moving the variator lens holding means in the optical axis direction by the driving source. A variator lens driving means attached to the lens barrel; a diaphragm main body disposed in the lens barrel for controlling the aperture; and a drive control unit for driving the diaphragm main body. A lens mirror comprising: an aperture unit attached to a lens barrel; and the focus lens driving device according to claim 6. Tube. 8. The variator lens driving means, wherein the drive source of the variator lens driving means and the drive control unit of the diaphragm unit are provided in a direction orthogonal to the magnetization direction of the magnet when viewed from the optical axis direction. The lens barrel according to claim 7, wherein the drive source and the drive control unit of the aperture unit are configured to face each other with an optical axis interposed therebetween, and are attached to the lens barrel. 9. The apparatus according to claim 3, wherein the position of the center of gravity of the lens driving member is provided outside of between two sides of the coil facing the magnetizing direction of the magnet when viewed from the optical axis direction. Lens driving device. 10. The first guide means for guiding movement of the movable lens group in the optical axis direction, and the first guide means for holding the movable lens group and fitting with the first guide means.
The lens holding means provided with a sleeve, and a function provided to each of the lens barrel and the lens holding means to move the lens holding means.
A lens driving device comprising: a plurality of the driving units; and a position detecting unit that functions to detect the position of the moving lens group and that is provided to face the lens barrel and the lens holding unit. Disposing the driving unit and the position detecting unit near the first sleeve of the lens holding unit when viewed from the optical axis direction, and by moving the moving lens group and the lens holding unit when viewed from the optical axis direction. A lens driving device, wherein a position of a center of gravity of the lens driving body including means, the driving means, and the position detecting means is arranged near the driving means.