JP2006271052A - Driving device, optical path changing device using the same, image projection device using optical path changing device, optical equipment moving device using driving device, and focusing device using optical equipment moving device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a driving device, along with an applied device using the same, capable of driving an object with precision by small amount, in a simple structure. <P>SOLUTION: A movable plate 16 that supports a drive shaft 15 is caulked and fixed to an elastic piece 13 formed to a support plate 14. The movable plate 16 is arranged between an upper coil 11A and a lower coil 11B with short intervals from both of them. With this configuration, the structure of a driving device 10 is simplified. The drive shaft 15 can be precisely driven by a small amount only by changing the amount of current flowing the upper coil 11A and the lower coil 11B, simplifying a control mechanism as well. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention provides a driving device capable of accurately driving a driven object by a minute amount, an optical path changing device using the driving device, an image projecting device capable of improving the resolution of a projected image, and a lens assembly. The present invention relates to an optical device moving device that can be driven by a minute amount and a focusing device that can focus with high accuracy.

  Patent Document 1 below discloses an optical path changing unit that changes an optical path of light from an image display device and a driving device that drives the optical path changing unit.

  FIG. 12 is a diagram for explaining the operation of the optical path changing means. The LCD display device 400 is disposed above (in the Z1 direction) orthogonal to the optical axis direction of the eyepiece 401, and the LCD display surface 400a faces down (in the Z2 direction). The light L emitted from the LCD display surface 400 a is bent in the optical axis direction of the eyepiece 401 by the reflecting mirror 402.

  The reflecting mirror 402 is rotatably supported by a support bar 403 that extends in a direction parallel to the LCD display surface 400a. The reflecting mirror 402 is connected via a flexible hinge 406 to a driving piece 405 that is reciprocated in the vertical direction by a voice coil 404. The voice coil 404 is driven by a drive circuit 407.

When the driving piece 405 is moved upward, for example, by the voice coil 404, the reflecting mirror 402 rotates by a rotation angle Δθ in the direction of the arrow in the drawing with the support rod 403 as a rotation axis. Then, the optical path r of the emitted light L from the LCD display surface 400a is changed from the dotted line direction to the solid line direction, and an optical pixel shift is performed.
JP-A-6-324320

  In the invention described in Patent Document 1, the structure in which the drive piece 405 is reciprocated up and down is not clearly described.

  Further, when a general DC motor or stepping motor is used as a driving device for driving a driven object such as the driving piece 405 of Patent Document 1 by a minute distance, the rotational motion of these motors is reduced to a minute. A mechanism such as a plurality of gears for converting the linear motion into a long distance is required, and the mechanism of the driving device becomes complicated. And it becomes easy to produce the problem that it becomes difficult to drive only a minute distance with high accuracy.

  In addition, the optical path changing device using such a driving device has a complicated structure and causes a problem that the optical path cannot be changed with high accuracy.

  Further, when the image projection apparatus is configured using the optical path changing apparatus as described above, the accuracy of the optical path change of the light from the image display apparatus constituting the image projection apparatus is poor, and as a result, the resolution of the image from the image display apparatus It becomes difficult to improve.

  Alternatively, if an optical device moving device for moving an optical device such as a lens assembly is configured using the driving device, the accuracy when the optical device is moved by a small amount is deteriorated.

  In addition, the focus device using the optical device moving device has a complicated structure, cannot focus accurately, and the optical device moving device is driven through a gear or the like. There is a problem that occurs.

  The present invention solves the above-described conventional problems, and has a simple structure that can accurately drive a driven object by a minute amount, and a simple structure that can change an optical path with high accuracy. The optical path changing device using the driving device and the image projecting device using the optical path changing device capable of improving the resolution of the projected image, and driving the lens assembly by a minute amount with a simple structure. The optical device moving device using the driving device that can be used, and the optical device moving device that has a simple structure, can focus accurately, and can reduce sound during driving. The object is to provide a focusing device.

  The drive device of the present invention includes a housing, an upper coil and a lower coil that generate a magnetic field, a movable plate made of a magnetic material, and a support plate made of a nonmagnetic material, and the support plate has an elastic piece. Provided, the movable plate is fixed to the elastic piece, and the movable plate is separated from the upper coil side and the lower coil by a minute gap between the upper coil and the lower coil. It is provided to be movable to the side.

  In the driving device of the present invention, the structure for driving the movable plate by a minute amount in the vertical direction is provided with the upper coil and the lower coil as described above, and the movable plate is provided with a minute gap between the two coils. It is the structure. For this reason, a structure can be simplified compared with the case where a general DC motor or a stepping motor is used. In addition, the movable plate can be accurately driven by a minute amount only by changing the amount of current flowing through the upper coil and the lower coil, and the control mechanism can be simplified.

  In the optical path changing device of the present invention, the fixing device is provided with the driving device and a mirror that is rotatably supported, and the driving shaft provided in the driving device is displaced from the rotating shaft of the mirror. It is connected to the position.

  Since the optical path changing device of the present invention has the above-described structure using the driving device having a simple structure, the structure is simple. Since the mirror is controlled only by changing the amount of current flowing through the upper coil and the lower coil, the mirror swing angle can be accurately changed by a minute amount, and as a result, the optical path can be changed accurately. can do.

The image projection device of the present invention includes the optical path changing device and an image display device.
In such an image projection apparatus, since the optical path changing device is used, the optical path is accurately changed, and the resolution of an image projected by the image display device can be reliably improved.

  In the optical apparatus moving device according to the present invention, a lens assembly is supported by the movable plate in the driving device.

  The structure for driving the lens assembly by a minute amount in the vertical direction in the optical apparatus moving apparatus of the present invention is provided with an upper coil and a lower coil, and supports the lens assembly with a minute gap between the two coils. The movable plate is provided. For this reason, the structure can be simplified as compared with the case of using a general DC motor or stepping motor as in the prior art.

  The movement amount of the lens assembly is also controlled by changing the amount of current flowing through the upper coil and the lower coil, similarly to the control of the movement amount of the drive shaft in the optical path changing device. Therefore, the lens assembly can be accurately driven by a minute amount only by changing the amount of current flowing through the upper coil and the lower coil, and the control mechanism can be simplified.

  The focus device of the present invention includes the optical device moving device, an image sensor that displays an image of an object, and a detection circuit that detects a contrast of an image displayed on the image sensor.

  Since the focus device of the present invention has the above-described structure using the optical device moving device having a simple structure, the structure is simple. Further, since the optical device moving device is not driven via a gear or the like as in the case of using a conventional stepping motor, the driving sound during driving can be reduced. Since the movement amount of the lens assembly is controlled by the control method, the movement amount of the lens assembly can be accurately changed by a minute amount, and as a result, the focus movement can be performed with high accuracy. .

  In the driving apparatus of the present invention, the driven object can be driven by a minute amount with high accuracy with a simple structure.

  In addition, the optical path changing device using the driving device of the present invention can change the optical path with a simple structure and with high accuracy.

  In addition, in the image projection apparatus using the optical path changing device of the present invention, the resolution of the projected image can be improved reliably.

  Alternatively, in the optical device moving device of the present invention, the lens assembly can be driven by a minute amount with high accuracy.

  In addition, in the focus device using the optical device moving device of the present invention, it is possible to focus with high accuracy with a simple structure and to reduce the sound during driving.

  FIG. 1 is a perspective view showing a drive device of the present invention, FIG. 2 is an exploded perspective view of the drive device shown in FIG. 1, and FIG. 3 is a partial sectional view taken along line 3-3 in FIG. In FIG. 3, since the inside of the drive device is symmetric with respect to the drive shaft, only the members on one side are denoted by reference numerals.

  In the driving device 10 of the present invention, as shown in FIGS. 1 to 3, an elastic piece 13 such as a plurality of leaf springs is formed in a housing 12 provided with an upper coil 11A on the lower side (Z2 direction in the drawing). The support plate 14 and the movable plate 16 that supports the drive shaft 15 at the center thereof are incorporated. A bottom plate 18 provided with a cover plate 17 and a lower coil 11B is attached to a housing 12 in which a support plate 14 and a movable plate 16 are incorporated by screws 19 or the like. An insertion hole 17a is formed at the center of the lid plate 17, and the drive shaft 15 is inserted into the insertion hole 17a and protrudes upward (in the Z1 direction in the drawing) from the lid plate 17 as shown in FIG. ing.

  As shown in FIG. 2, a plurality of elastic pieces 13 are formed in a predetermined circumferential shape at an equal pitch, and can be elastically deformed in the vertical direction. The elastic piece 13 may be formed by cutting and raising a support plate 14 made of a nonmagnetic material such as stainless steel, or the elastic piece 13 made of a nonmagnetic material such as stainless steel is formed on the support plate 14. And may be provided separately.

  The movable plate 16 is made of a magnetic material such as iron and has a substantially circular shape, and a support hole 16a is formed at the center of the movable plate 16 as shown in FIGS. The drive shaft 15 has a substantially columnar shape, and a fitting groove 15a is formed on the outer periphery below the drive shaft 15. By fitting the fitting groove 15a into the support hole 16a, the drive shaft 15 extends from the support hole 16a. It is sandwiched and supported by the movable plate 16. A mounting piece 16 b is formed integrally with the movable plate 16 at a position corresponding to the protruding portion 13 a of the elastic piece 13 in the outer periphery of the movable plate 16. The attachment piece 16b may be provided separately from the movable plate 16. Each attachment piece 16b is fixed by caulking to the corresponding protrusion 13a.

  As shown in FIGS. 2 and 3, both the upper coil 11A and the lower coil 11B are wound in a donut shape in which a central portion is hollowed out from a disk shape, and have a predetermined width (the length in the Y1-Y2 direction in the drawing). ) W1 and thickness (length in the Z1-Z2 direction in the drawing) H1.

  The upper coil 11A is provided with an upper inner yoke 20A1 made of a magnetic material along its inner periphery and bent upward in the width direction so as to be substantially L-shaped. The upper outer yoke 20A2 is provided which is made of a magnetic material and whose upper portion is bent in the width direction to have a substantially L shape. The facing interval W2 between the bent portion 20A10 of the upper inner yoke 20A1 and the bent portion 20A20 of the upper outer yoke 20A2 is smaller than the width W1 of the upper coil 11A. The lower surface 20A12 of the vertical portion 20A11 of the upper inner yoke 20A1 and the lower surface 20A22 of the vertical portion 20A21 of the upper outer yoke 20A2 are both below the lower surface 11A1 of the upper coil 11A.

  An upper portion having a predetermined thickness between the bent portion 20A10 of the upper inner yoke 20A1 and the bent portion 20A20 of the upper outer yoke 20A2 and the upper coil 11A and having a width substantially the same as the width W1 of the upper coil 11A. A yoke 20a is provided along the upper surface 11A2 of the upper coil 11A. That is, as shown in FIG. 3, the upper yoke 20a is placed on the upper surface 11A2 of the upper coil 11A, the upper surface 20a1 of the upper yoke 20a is in contact with the bent portions 20A10 and 20A20, and the upper yoke 20a is fixed. Yes.

  Similarly to the case of the upper coil 11A, the inner and outer peripheries of the lower coil 11B are made of a magnetic material, and the upper part thereof is bent in the width direction so as to have a substantially L shape. An interval W2 between the bent portion 20B10 of the lower inner yoke 20B1 and the bent portion 20B20 of the lower outer yoke 20B2 facing each other is smaller than the width W1 of the lower coil 11B. The upper surface 20B12 of the vertical portion 20B11 of the lower inner yoke 20B1 and the upper surface 20B22 of the vertical portion 20B21 of the lower outer yoke 20B2 are both above the upper surface 11B1 of the lower coil 11B.

  A lower portion having a predetermined thickness between the bent portion 20B10 of the lower inner yoke 20B1 and the bent portion 20B20 of the lower outer yoke 20B2 and the lower coil 11B and having a width substantially the same as the width W1 of the lower coil 11B. A yoke 20b is provided along the lower surface 11B2 of the lower coil 11B. That is, as shown in FIG. 3, the lower yoke 20b is provided on the lower surface 11B2 of the lower coil 11B, the lower surface 20b1 of the lower yoke 20b is in contact with the bent portions 20B10 and 20B20, and the lower yoke 20b is fixed. .

  As shown in FIG. 3, the support plate 14 is fixed at a predetermined position inside the housing 12, and the movable plate 16 has a lower surface 20A12 of the vertical portion 20A11 of the upper inner yoke 20A1 and a vertical portion 20A21 of the upper outer yoke 20A2. The lower surface 20A22 is disposed at a position slightly separated from the lower surface ha, and the upper surface 20B12 of the vertical portion 20B11 of the lower inner yoke 20B1 and the upper surface 20B22 of the vertical portion 20B21 of the lower outer yoke 20B2 are disposed at positions separated by a minute space hb. The drive shaft 15 is disposed at a predetermined interval between the opposed upper inner yokes 20A1 and 20A1, and moves up and down together with the movable plate 16 according to the drive principle described later.

Next, the driving operation of the driving device 10 of the present invention will be described.
FIG. 4 is a cross-sectional view similar to FIG. 3 for explaining the drive principle and drive operation of the drive device of the present invention. In FIG. 4, the yokes are not hatched.

In FIG. 4, the same members and the like as those in FIG.
First, in an initial state in which no current is passed through the upper coil 11A and the lower coil 11B, the movable plate 16 has a lower surface 20A12 of the vertical portion 20A11 of the upper inner yoke 20A1 and an upper outer yoke 20A2 as shown in FIG. The vertical portion 20A21 of the vertical portion 20A21 is at a position slightly spaced apart from the lower surface 20A22, and the upper surface 20B11 of the lower inner yoke 20B1 and the lower outer yoke 20B2 of the vertical portion 20B21 of the vertical portion 20B21 are spaced apart from the upper surface 20B22 by a small distance hb. .

  From this initial state, when the current Ia is applied only to the upper coil 11A in the direction shown in FIG. 4, an upper magnetic field Ga having a magnetic flux density B is generated, and the upper magnetic field Ga passes through the upper inner yoke 20A1 from below to above. Then, it passes through the upper yoke 20a in the width direction, and passes through the upper outer yoke 20A2 from above to below. That is, in the cross section on the Y1 side shown in FIG. 4, the upper magnetic field Ga passes through each yoke in the counterclockwise direction as shown by the arrow, and clockwise in the cross section on the Y2 side shown in the figure. Pass in the direction. Here, since the upper surface 20a1 of the upper yoke 20a is in contact with the bent portion 20A10 of the upper inner yoke 20A1 and the bent portion 20A20 of the upper outer yoke 20A2, the magnetic path of the upper magnetic field Ga is closed on the upper side. . On the other hand, since there is a minute gap ha between the lower surface 20A12 of the vertical portion 20A11 of the upper inner yoke 20A1 and the lower surface 20A22 of the vertical portion 20A21 of the upper outer yoke 20A2, and the movable plate 16, this portion. In FIG. 3, the magnetic path of the upper magnetic field Ga is not closed, and the upper magnetic field Ga leaks from the portion of the minute interval ha. The upper inner yoke 20A1, the upper outer yoke 20A2, and the movable plate 16 are all made of a magnetic material, and the upper inner yoke 20A1 and the upper outer yoke 20A2 are fixed inside the casing 12, so A magnetic force f1 proportional to the square of the magnetic flux density B acts on the portion facing the lower surfaces 20A12 and 20A22 in the upward direction.

  On the other hand, since the movable plate 16 is caulked and fixed to the protruding portion 13a of the elastic piece 13 via the mounting piece 16b, the movable plate 16 is urged downward by a downward urging force f2. Therefore, the resultant force F of the magnetic force f1 and the biasing force f2 acts on the movable plate 16 upward. Then, the movable plate 16 moves upward, that is, toward the upper coil 11A through which the current Ia flows, and the drive shaft 15 also moves upward together with the movable plate 16.

  The magnetic force f1 is proportional to the square of the magnetic flux density B, and the magnetic flux density B is proportional to the current value of the current Ia. Therefore, when the current value of the current Ia is changed, the magnetic force f1 applied to the movable plate 16 can be changed. As a result, the resultant force F can be changed, and the upward movement amount s1 of the movable plate 16, that is, the upward movement amount s1 of the drive shaft 15 can be changed. That is, by controlling the current value of the current Ia flowing through the upper coil 11A, the upward movement amount s1 of the drive shaft 15 can be accurately controlled. The direction in which the current Ia flows may be opposite to the direction shown in FIG.

  Next, the current Ia is stopped from flowing through the upper coil 11A, and the current Ib is passed through the lower coil 11B only in the direction shown in FIG. Then, a lower magnetic field Gb (not shown) is generated as in the case where the current Ia is passed through the upper coil 11A. Since there is a small gap hb between the upper surface 20B12 of the vertical portion 20B11 of the lower inner yoke 20B1 and the upper surface 20B22 of the vertical portion 20B21 of the lower outer yoke 20B2, and the movable plate 16, a current is passed through the upper coil 11A. Based on the same principle as when Ia is passed, the movable plate 16 moves downward, that is, toward the lower coil 11B through which the current Ib is passed, and the drive shaft 15 also moves downward together with the movable plate 16. . The downward movement amount s2 of the drive shaft 15 is also accurately controlled by controlling the current value of the current Ib flowing through the lower coil 11B. The direction in which the current Ib flows may be opposite to the direction shown in FIG.

  By switching the current Ia through the upper coil 11A and the current Ib through the lower coil 11B by the control unit (not shown), the drive shaft 15 is moved between the minute intervals ha and hb. It can be moved up or down.

  In the driving apparatus of the present invention, the structure for driving the drive shaft 15 by a minute amount in the vertical direction is provided with the upper coil 11A and the lower coil 11B as described above, and the minute intervals ha and hb are provided between the two coils. Thus, the movable plate 16 that supports the drive shaft 15 is provided. For this reason, a structure can be simplified compared with the case where a general DC motor or a stepping motor is used. Further, the drive shaft 15 can be accurately driven by a minute amount only by changing the amount of current flowing through the upper coil 11A and the lower coil 11B, and the control mechanism can be simplified.

  5 is a perspective view showing an optical path changing device using the driving device of the present invention, FIG. 6 is a partial sectional view seen from the Y2 side, illustrating the operation of the light reflecting device shown in FIG. 5, and FIG. It is a fragmentary sectional view seen from illustration X1 side explaining operation | movement of the light reflection apparatus shown. 5 to 7, the shape of the drive shaft is schematically shown, and the thickness is shown constant. In FIG. 6, the magnet and the Hall element are not hatched.

  In FIG. 5, members similar to those in FIGS. 1 to 3 are denoted by the same reference numerals, and description thereof is omitted.

  The optical path changing device 100 reflects light L emitted from an image display device K such as an LCD (liquid crystal display device) by a mirror M to project an image K0 at a predetermined position. Then, by swinging the mirror M by a minute angle, the optical path r of the light L, particularly the reflected optical path, is slightly changed, and the position of the pixel of the image K0 to be projected is apparently slightly moved, and the apparent number of pixels To increase the resolution of the image K0.

  The optical path changing device 100 has a fixing device 101, and the driving device 10 shown in FIG. 1 is placed on the X1 side in the drawing and on the Y1 side from the center of the bottom plate 101a of the fixing device 101. Above the inside of the fixing device 101, a mirror M having a predetermined thickness and a predetermined area is provided on a support member 102a provided on the side wall 101b on the Y1 side of the fixing device 101 and on the Y2 side of the fixing device 101 in the Y2 side. The support member 102b provided on the side wall 101c can swing in the α1 direction and the α2 direction shown in the figure, that is, in the clockwise direction and the counterclockwise direction when viewed from the Y2 side as an axis passing through the support members 102a and 102b. It is supported by. The mirror M is also supported by a support portion (not shown) provided on the side wall 101e on the X1 side of the fixing device 101. The mirror M is supported by the support part by, for example, fitting the mirror M and the support part into an uneven shape. The support members 102a and 102b are provided so as to be movable up and down, and are pressed downward from above by elastically deformable pressing members 103 and 103 in order to restrict the amount of upward movement. The mirror M is supported by the support part provided on the side wall 101e on the X1 side of the fixing device 101, and the support members 102a and 102b can move up and down. Therefore, the mirror M passes through the support part. The shaft extending in the X1-X2 direction can be swung in the β1 and β2 directions shown in the drawing, that is, in the clockwise and counterclockwise directions as viewed from the X1 side. The lower surface of the mirror M is joined to the upper surface of the drive shaft 15 by a joining means.

  As shown in FIG. 6, the end of the mirror M on the X2 side, that is, the end opposite to the portion joined to the drive shaft 15 is magnetized with an N pole on the upper surface of the mirror M. A magnet 103a is provided, and a magnet 103b magnetized to an S pole is provided on the lower surface of the mirror M. A magnet magnetized to the S pole may be provided on the upper surface of the mirror M, and a magnet magnetized to the N pole may be provided on the lower surface of the mirror M.

  A Hall element 104 is provided between the height position of the magnet 103a and the height position of the magnet 103b inside the side wall 101d on the X2 side of the fixing device 101 in the figure.

Next, the operation of the optical path changing device 100 will be described.
In the initial state where the drive shaft 15 is not moving, the mirror M is parallel to the XY plane, that is, horizontal, as shown by the solid line in FIG. At this time, the light L travels on an optical path r0 as shown by a solid line in FIG. 6, and an image K0 is displayed at a predetermined position. In the following, the light L enters from the obliquely upper side of the optical path changing device 100 on the X1 side in the figure, is reflected in the X2 direction by the mirror M, and the image K0 is further provided on the X2 side of the optical path changing apparatus 100 in the figure. A case where the image is displayed on Sc will be described as an example.

  From the initial state, for example, when the current Ia is supplied only to the upper coil 11A of the drive device 10, the drive shaft 15 moves upward according to the drive principle. Then, as shown in FIG. 6, the drive device 10, that is, the drive shaft 15 is joined to the mirror M on the X1 side of the mirror M from the rotation axis m <b> 1, so the mirror M attaches the support members 102 a and 102 b. It swings in the α1 direction shown in the figure as a fulcrum. At this time, the optical path r of the light L is changed from the optical path r0 to the optical path r1 indicated by the dotted line in FIG. As a result of this optical path change, the pixel position of the image K0 moves slightly downward from the initial position when the driving device 10 is in the initial state, as shown by the arrow in FIG. Further, as shown in FIG. 7, since the drive shaft 15 is joined to the mirror M on the Y1 side of the rotation axis m2 of the mirror M, the mirror M moves upward and the support member 102a. Through the downward movement of 102b, it swings also in the β1 direction shown in the figure. At this time, the optical path r of the light L is changed from the optical path r0 to the Y2 side (right direction) in the figure. Then, by this optical path change, the pixel position of the image K0 moves slightly to the right from the initial position. Accordingly, when the drive shaft 15 moves upward, the pixel position of the image K0 moves slightly downward and to the right from the initial position. For this reason, the apparent number of pixels of the image K0 is increased, and the resolution of the image K0 is improved.

  When the drive shaft 15 is moved downward, the mirror M swings in the illustrated α2 direction and the illustrated β2 direction, the optical path r of the light L is changed accordingly, and the pixel position of the image K0 is changed to the initial position. Move slightly up and left. Also in this case, the apparent number of pixels of the image K0 is increased, and the resolution of the image K0 is improved.

  The oscillating angle θα in the α direction and the oscillating angle θβ in the β direction of the mirror M, that is, the moving amount s1 upward or the downward moving amount s2 of the drive shaft 15 are the magnets 103a and 103b and the holes. It is controlled by the element 104. When the mirror M swings in the illustrated α1 or α2 direction, the magnets 103a and 103b swing in the illustrated α1 or α2 direction, and when the mirror M swings in the illustrated β1 or β2 direction, the magnets 103a and 103b are also illustrated. Swings in the β1 or β2 direction. Then, the magnetic flux density Bh passing through the Hall element 104 changes from the magnetic flux density Bh0 when the driving device 10 is in the initial state. The Hall element 104 detects the change in the magnetic flux density Bh as a change in voltage, detects the swing angles θα and θβ of the mirror M based on the change in voltage, detects the position of the mirror M, and sends the detection signal to the above-mentioned detection signal. Send to the control unit. The controller controls the upper coil so as to achieve desired swing angles θα, θβ based on the sent detection signal, that is, to move the drive shaft 15 by a desired movement amount s1 or s2. The amount of current Ia flowing through 11A or current Ib flowing through the lower coil 11B is controlled. With this control method, the drive shaft 15 can be accurately moved by a minute amount, and the swing angles θα and θβ of the mirror M can be accurately changed by a minute amount.

  Contrary to the above, the Hall element 104 is provided on the upper surface or the lower surface of the end portion on the X2 side of the mirror M, and the magnets 103a and 103b are disposed on the inner side of the side wall 101d on the X2 side of the fixing device 101. The Hall element 104 may be provided between the height positions 103a and 103b.

  In the above, the drive shaft 15 is joined to the mirror M on the X1 side in the drawing with respect to the rotation axis m1 of the mirror M and on the Y1 side in the drawing with respect to the rotation shaft m2, but is not limited thereto. If the mirror M can be swung in the illustrated α1 direction or α2 direction and the illustrated β1 direction or β2 direction by the drive shaft 15, the drive device 10 is closer to the illustrated X1 side than the center of the bottom plate 101a of the fixing device 101, and Mounted on the Y2 side in the figure, on the X2 side in the figure and on the Y1 side in the figure, or on the X2 side in the figure and on the Y2 side in the figure, the drive shaft 15 rotates on the X1 side in the figure with respect to the rotation axis m1 of the mirror M. The Y2 side in the drawing from the moving shaft m2, the X2 side in the drawing from the rotating shaft m1, and the Y1 side in the drawing from the rotating shaft m2, or the X2 side in the drawing from the rotating shaft m1 and the rotating shaft m2. Mirror M on the Y2 side It may be joined. That is, the drive shaft 15 only needs to be joined to the mirror M at a position shifted from the rotation axes m1 and m2 of the mirror M.

  Since the optical path changing device 100 of the present invention has the above-described structure using the driving device 10 having a simple structure, the structure is simple. Since the mirror M is controlled by the control method, the swing angles θα and θβ of the mirror M can be accurately changed by a minute amount, and as a result, the optical path r can be changed with high accuracy.

  Further, the optical path changing device 100 can be incorporated into the image projection device T that projects the image K0 at a predetermined position together with the image display device K. In the image projection device T, since the optical path changing device 100 is used, the optical path is changed with high accuracy, and the resolution of the image K0 can be reliably improved.

  8 is a perspective view showing the optical device moving apparatus of the present invention, FIG. 9 is an exploded perspective view of the optical apparatus moving device shown in FIG. 8, and FIG. 10 is a cross-sectional view taken along line 1-1 in FIG. In FIG. 10, since the inside of the driving device is symmetric with respect to the lens module, only the members on one side are denoted by reference numerals.

  8 to 10, members similar to those in FIGS. 1 to 3 are denoted by the same reference numerals, and description thereof is omitted.

  Unlike the driving device 10 shown in FIGS. 1 to 3, the optical device moving device 200 supports a lens module (lens assembly) 22 having a lens 21 at the center of the movable plate 16. The cover plate 17 is made of a magnetic material, and a through hole 17b is formed at the center thereof. A position corresponding to the through hole 17b on the lower surface 17A of the cover plate 17 is smaller than the radius of the through hole 17b. A cylindrical guide cylinder 17c having a large radius is also provided. The upper inner yoke 20A1 and the upper outer yoke 20A2 are integrally formed with the cover plate 17, and the upper inner yoke 20A1 and the upper outer yoke 20A2 are connected together by a connecting portion 20A3 which is a part of the cover plate 17 and integrated therewith. It has become. Similarly, the lower inner yoke 20B1 and the lower outer yoke 20B2 are integrally formed with the bottom plate 18 made of a magnetic material, and the lower inner yoke 20B1 and the upper outer yoke 20B2 are below and a connecting portion that is a part of the bottom plate 18. It is connected and united by 20B3. These points are different from the driving device 10, and other members and the like are the same as the members of the driving device 10 although some of them have different shapes. Note that a plurality of lenses may be incorporated in the lens module 22.

  The driving operation of the optical device moving device 200 is performed according to the same driving principle as that of the driving device 10 described above, and the lens module 22 is moved in the vertical direction as the movable plate 16 moves.

  In the optical apparatus moving apparatus 200, the lens module 22 is driven by a minute amount in the vertical direction, as described above, the upper coil 11A and the lower coil 11B are provided, and the minute gaps ha and hb are provided between the two coils. Thus, the movable plate 16 that supports the lens module 21 is provided. For this reason, the structure can be simplified as compared with the case of using a general DC motor or stepping motor as in the prior art.

  Further, the movement amount of the lens module 22 is also controlled by changing the amount of current flowing through the upper coil 11A and the lower coil 11B, similarly to the control of the movement amount of the drive shaft 15 of the drive device 10. Therefore, the lens module 22 can be accurately driven by a minute amount only by changing the amount of current flowing through the upper coil 11A and the lower coil 11B, and the control mechanism can be simplified.

FIG. 11 is a perspective view showing a focus device using the optical device moving device shown in FIG.
The focus device 300 includes an optical device moving device 200, an image sensor 301 such as a CMOS (Complementary Metal-Oxide Semiconductor), and a detection circuit (not shown) that detects contrast data of an image displayed on the image sensor 301. For example, it is used as a focus device for so-called autofocus of a small camera or a general digital camera mounted on a mobile phone.

  In the focusing device 300, the lens module 22 is first moved upward from the initial position (initial position) where no current is passed through the upper coil 11A and the lower coil 11B according to the driving principle of the optical device moving apparatus 200. Move to the uppermost position, move downward from the uppermost position to move to the lowermost position, move upward from the lowermost position, and return to the initial position. That is, the distance between the lens 21 of the lens module 22 and the image sensor 301 is changed. During this series of movements, when the lens module 22 is at a predetermined position, that is, when the distance between the lens 21 and the image sensor 301 is a predetermined distance, a subject (object) displayed on the image sensor 301. The contrast is detected by the detection circuit. Thereafter, the lens module 22 is moved to the position where the contrast value of the subject is the highest by the driving principle. Then, the subject is photographed by the camera. Contrary to the above, the lens module 22 is moved from the initial position to the lowermost position and moved to the lowermost position, and moved from the lowermost position to the uppermost position. To the initial position by moving downward from the uppermost position.

  Since the focus apparatus 300 of the present invention has the above-described structure using the optical device moving apparatus 200 having a simple structure, the structure is simple. Moreover, since the optical apparatus moving apparatus 200 is not driven via a gear or the like as in the case of using a conventional stepping motor, the driving sound during driving can be reduced. Since the movement amount of the lens module 22 is controlled by the control method, the movement amount of the lens module 22 can be accurately changed by a minute amount, and as a result, the focus movement of the camera is accurately performed. be able to.

The perspective view which shows the drive device of this invention, 1 is an exploded perspective view of the drive device shown in FIG. FIG. 1 is a partial cross-sectional view taken along line 3-3 in FIG. FIG. 3 is a cross-sectional view similar to FIG. 3 for explaining the driving principle and driving operation of the driving device of the present invention; The perspective view which shows the optical path changing apparatus using the drive device of this invention, FIG. 5 is a partial cross-sectional view illustrating the operation of the light reflecting device shown in FIG. FIG. 5 is a partial cross-sectional view illustrating the operation of the light reflecting device shown in FIG. The perspective view which shows the optical apparatus moving apparatus of this invention, The disassembled perspective view of the optical apparatus moving apparatus shown in FIG. Arrow sectional drawing in the 1-1 line of FIG. The perspective view which shows the focus apparatus using the optical apparatus moving apparatus shown in FIG. The figure explaining operation | movement of the conventional optical path change means

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Drive apparatus 11A Upper coil 11B Lower coil 12 Case 13 Elastic piece 14 Support plate 15 Drive shaft 16 Movable plate 22 Lens module 100 Optical path changing apparatus 103a, 103b Magnet 104 Hall element 200 Optical apparatus moving apparatus 300 Focus apparatus 301 Imaging element K Image display device M Mirror T Image projection device f1 Magnetic force ha, hb Minute spacing

Claims (5)

  A housing, an upper coil and a lower coil that generate a magnetic field, a movable plate made of a magnetic material, and a support plate made of a nonmagnetic material, an elastic piece is provided on the support plate, It is fixed to the elastic piece, and the movable plate is movably provided on the upper coil side and the lower coil side with a small space between the upper coil and the lower coil. A drive device characterized by that.   The driving device according to claim 1 and a mirror that is rotatably supported are provided in the fixing device, and the driving shaft provided in the driving device is connected to a position shifted from the rotating shaft of the mirror. The optical path changing device.   An image projection apparatus comprising the optical path changing apparatus according to claim 2 and an image display apparatus.   2. The optical apparatus moving device according to claim 1, wherein a lens assembly is supported on the movable plate.   5. A focus device comprising: the optical device moving device according to claim 4; an image sensor that displays an image of an object; and a detection circuit that detects a contrast of the image displayed on the image sensor.

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