Optical unit with shake correcting function

An optical unit may include a fixed body; a movable module which holds an optical element; a swing support point which swingably supports the movable module; a shake correction drive mechanism which swings the movable module with the swing support point as a swing center around two axial lines intersecting an optical axis direction of the optical element between an outer peripheral face of the movable module and the fixed body; a first photo reflector provided between a bottom part of the movable module and the fixed body at a position superposing on one of the two axial lines and that detects displacement of the movable module; and a second photo reflector provided between the bottom part of the movable module and the fixed body at a position superposing on the other of the two axial lines and that detects displacement of the movable module.

CROSS REFERENCE TO RELATED APPLICATION

This is a U.S. national stage of application No. PCT/JP2011/061815, filed on 24 May 2011. Priority under 35 U.S.C. §119(a) and 35 U.S.C. §365(b) is claimed from Japanese Application No. 2010-131389, filed 8 Jun. 2010, the disclosure of which are also incorporated herein by reference.

TECHNICAL FIELD

The present invention relates to an optical unit with a shake correcting function which is mounted on a cell phone with a camera or the like.

BACKGROUND

In recent years, an optical device such as a cell phone is structured on which an optical unit for photographing is mounted. In the optical unit, in order to restrain or reduce any disturbance of a photographed image due to a shake in the hand of a user, a technique has been proposed in which an angular velocity sensor, a photo reflector and a shake correction drive mechanism are disposed around a lens and, on the basis of a detection result for a shake by the angular velocity sensor, the shake correction drive mechanism is controlled and the position of the lens is monitored by the photo reflector (see Patent Literature 1).[PTL 1] Japanese Patent Laid-Open No. 2002-207148

However, like the structure described in Patent Literature 1, when the photo reflector and the shake correction drive mechanism are disposed around the lens, a size in a direction intersecting an optical axis direction becomes extremely large. This problem is not limited to a case that a shake of hand is corrected in an optical unit for photographing and is common to a case that a shake is corrected in an optical unit.

SUMMARY

In view of the problem described above, at least an embodiment of the present invention provides an optical unit with a shake correcting function in which the increase of size in the optical axis direction and the direction intersecting the optical axis direction can be restrained even when a photo reflector and a shake correction drive mechanism are provided on the movable module having an optical element.

In order to attain the above, at least an embodiment of the present invention provides an optical unit with a shake correcting function including a fixed body, a movable module which holds an optical element, a swing support point which swingably supports the movable module between a bottom part of the movable module and the fixed body, a shake correction drive mechanism which is structured to swing the movable module with the swing support point as a swing center around two axial lines intersecting an optical axis direction of the optical element between an outer peripheral face of the movable module and the fixed body, a first photo reflector which is provided between the bottom part of the movable module and the fixed body at a position superposing on one of the two axial lines in the optical axis direction and is structured to detect displacement of the movable module, and a second photo reflector which is provided between the bottom part of the movable module and the fixed body at a position superposing on the other of the two axial lines in the optical axis direction and is structured to detect displacement of the movable module.

In the optical unit with a shake correcting function (optical unit) in accordance with at least an embodiment of the present invention, a shake correction drive mechanism for swinging the movable module is provided and thus, when a shake such as a hand shake occurs in the optical unit, the movable module can be swung so as to cancel the shake. Therefore, even when the optical unit is shaken, inclination of the optical axis can be corrected. Further, in two axial lines when the movable module is to be swung, the first photo reflector is provided at the position superposing on one of the axial lines in the optical axis direction and the second photo reflector is provided at the position superposing on the other axial line in the optical axis direction and thus, respective shakes of the movable module for two axial lines are monitored and controlled by the first photo reflector and the second photo reflector. In addition, the shake correction drive mechanism is provided between the outer peripheral face of the movable module and the fixed body, and the first photo reflector and the second photo reflector are provided by utilizing a space where the swing support point is provided between the bottom part of the movable module and the fixed body. Therefore, even when the photo reflector and the shake correction drive mechanism are provided on the movable module, the increase of size in the optical axis direction and the direction intersecting the optical axis direction can be restrained.

In at least an embodiment of the present invention, it is preferable that the optical unit with a shake correcting function includes a flexible circuit board which is extended in a direction intersecting the optical axis direction between the bottom part of the movable module and the fixed body so as to avoid positions superposing on the first photo reflector and the second photo reflector in the optical axis direction. Each of the first photo reflector and the second photo reflector is provided with a rectangular planar shape and extended directions of long sides of the first photo reflector and the second photo reflector are parallel to an extended direction of the flexible circuit board. According to this structure, a region where the first photo reflector and the second photo reflector occupy in a widthwise direction of the flexible circuit board is narrow and thus the flexible circuit board can be extended with a wide width dimension.

In at least an embodiment of the present invention, it is preferable that the first photo reflector and the second photo reflector are disposed so that their respective light emitting parts are set close to each other or their respective light receiving parts are set close to each other. According to this structure, a sufficient distance is secured between the light emitting part of the first photo reflector and the light receiving part of the second photo reflector and between the light emitting part of the second photo reflector and the light receiving part of the first photo reflector and thus a cross talk between the first photo reflector and the second photo reflector can be prevented.

In at least an embodiment of the present invention, it is preferable that the optical unit with a shake correcting function includes a light shielding layer which is provided on at least two side faces of four side face parts of the first photo reflector in which the four side face parts are set in directions intersecting the optical axis direction, at least the two side faces being disposed on a side where the second photo reflector is located, and a light shielding layer which is provided on at least two side faces of four side face parts of the second photo reflector in which the four side face parts are set in directions intersecting the optical axis direction, at least the two side faces being disposed on a side where the first photo reflector is located. According to this structure, the light emitted from the light emitting part of the first photo reflector is prevented from being incident on the light receiving part of the second photo reflector and the light emitted from the light emitting part of the second photo reflector is prevented from being incident on the light receiving part of the first photo reflector and thus a cross talk between the first photo reflector and the second photo reflector can be prevented.

In at least an embodiment of the present invention, it is preferable that the optical unit with a shake correcting function includes a first reflection part which is provided in the fixed body so as to superpose on the first photo reflector in the optical axis direction, and a second reflection part which is provided in the fixed body so as to superpose on the second photo reflector in the optical axis direction. The first photo reflector and the second photo reflector are provided in the bottom part of the movable module, and the first reflection part and the second reflection part are recessed in a direction apart from the bottom part of the movable module with respect to a portion of the fixed body which is located around the first reflection part and a portion of the fixed body which is located around the second reflection part. According to this structure, even in a case that a sufficient distance is required to secure between the first photo reflector and the first reflection part and between the second photo reflector and the second reflection part, a portion close to the bottom part of the movable module can be provided in the fixed body. Therefore, when the swing support point is provided at the close portion, a region where the swing support point occupies is narrowed. Accordingly, a space for disposing the first photo reflector and the second photo reflector can be secured between the bottom part of the movable module and the fixed body.

In at least an embodiment of the present invention, it may be structured that the optical unit with a shake correcting function includes a first reflection part which is provided in the fixed body so as to superpose on the first photo reflector in the optical axis direction, and a second reflection part which is provided in the fixed body so as to superpose on the second photo reflector in the optical axis direction. The first photo reflector and the second photo reflector are provided in the bottom part of the movable module, and the first reflection part and the second reflection part are formed in the same plane with respect to a portion of the fixed body which is located around the first reflection part and a portion of the fixed body which is located around the second reflection part.

In at least an embodiment of the present invention, it is preferable that a portion of the fixed body which faces the bottom part of the movable module is structured of a metal member that is non-magnetized by heat treatment. In a case that a portion in the fixed body which faces the bottom part of the movable module is to be structured, when machine working is performed on metal material such as SUS304, the metal material may be provided with magnetic property. However, when the metal material is non-magnetized by heat treatment, attraction and the like to the permanent magnet can be prevented at the time of assembling the optical unit. Further, when heat treatment is performed on the metal material such as SUS304, its reflectance becomes high and thus the first reflection part and the second reflection part having high reflectance are obtained.

In at least an embodiment of the present invention, it is preferable that the bottom part of the movable module includes a circuit board on which the first photo reflector and the second photo reflector are mounted, and a face of the circuit board on an opposite side to a face where the first photo reflector and the second photo reflector are mounted is mounted with an imaging element. According to this structure, the first photo reflector and the second photo reflector are mounted on the same circuit board for the imaging element and thus the number of part items is reduced.

In the optical unit with a shake correcting function (optical unit) in accordance with at least an embodiment of the present invention, a shake correction drive mechanism for swinging the movable module is provided and thus, when a shake such as a hand shake occurs in the optical unit, the movable module can be swung. Therefore, even when the optical unit is shaken, inclination of the optical axis can be corrected. Further, in two axial lines when the movable module is to be swung, the first photo reflector is provided at the position superposing on one of the axial lines in the optical axis direction and the second photo reflector is provided at the position superposing on the other axial line in the optical axis direction and thus, respective shakes of the movable module are controlled for the two axial lines. In addition, the shake correction drive mechanism is provided between the outer peripheral face of the movable module and the fixed body, and the first photo reflector and the second photo reflector are provided by utilizing a space where the swing support point is provided between the bottom part of the movable module and the fixed body. Therefore, even when the photo reflector and the shake correction drive mechanism are provided on the movable module, the increase of size in the optical axis direction and the direction intersecting the optical axis direction can be restrained.

DESCRIPTION OF EMBODIMENTS

Embodiments of the present invention will be described below with reference to the accompanying drawings. In the following description, a structure for preventing a hand shake in a photographing unit will be described as an example for an optical element unit. Further, in the following description, three directions perpendicular to each other are set to be an “X”-axis, a “Y”-axis and a “Z”-axis and a direction along an optical axis “L” (lens optical axis) is set to be the “Z”-axis. Further, in the following description, regarding swings of the respective directions, turning around the “X”-axis corresponds to a so-called pitching (vertical swing), turning around the “Y”-axis corresponds to a so-called yawing (lateral swing), and turning around the “Z”-axis corresponds to a so-called rolling. Further, “+X” is indicated on one side of the “X”-axis, “−X” is indicated on the other side, “+Y” is indicated on one side of the “Y”-axis, “−Y” is indicated on the other side, “+Z” is indicated on one side (opposite side to an object side) of the “Z”-axis, and “−Z” is indicated on the other side (object side).

First Embodiment

Entire Structure of Optical Unit for Photographing

FIG. 1is an explanatory view schematically showing a state in which an optical unit with a shake correcting function in accordance with a first embodiment of the present invention is mounted on an optical device such as a cell phone.FIGS. 2(a) and2(b) are perspective views showing an outward appearance of the optical unit with a shake correcting function and the like in accordance with the first embodiment of the present invention.FIG. 2(a) is a perspective view showing the optical unit which is viewed from an object side andFIG. 2(b) is a perspective view showing the optical unit which is viewed from an opposite side to the object side.

An optical unit100(optical unit with a shake correcting function) shown inFIG. 1is a thin camera used in an optical device1000such as a cell phone with a camera and is mounted in a supported state by a chassis1100(device main body) of the optical device1000. In the optical unit100, when a shake such as a hand shake is occurred in the optical device1000at the time of photographing, disturbance occurs in a photographed image. Therefore, in the optical unit100in this embodiment, as described below, a movable body3including a photographing unit1is supported within a fixed body200so as to be capable of being swung and the optical unit100is provided with a shake correction drive mechanism (not shown inFIG. 1) which swings the photographing unit1on the basis of a detection result for a hand shake by a gyroscope (not shown) mounted on the optical unit100or a gyroscope (not shown) mounted on a main body side of the optical device1000.

As shown inFIG. 1andFIGS. 2(a) and2(b), flexible circuit boards410and420are extended out from the optical unit100for supplying power to the photographing unit1and the shake correction drive mechanism. The flexible circuit boards410and420are electrically connected with a host control section or the like which is provided in a main body of the optical device1000through a common connector490or the like. Further, the flexible circuit board410is also provided with a function for outputting a signal from the photographing unit1. Therefore, the number of wiring lines in the flexible circuit board410is large and thus a relatively wide flexible circuit board410is used.

FIG. 3is a cross-sectional view schematically showing a structure of the photographing unit1which is mounted on the optical unit100with a shake correcting function in accordance with the first embodiment of the present invention.FIG. 4is an exploded perspective view showing the photographing unit1which is mounted on the optical unit100with a shake correcting function in accordance with the first embodiment of the present invention.

As shown inFIGS. 3 and 4, the photographing unit1is, for example, an optical element unit which moves a plurality of lenses1aas an optical element (seeFIG. 1) in both directions, i.e., in an “A”-direction (front side) approaching an object to be photographed (object side) along a direction of the optical axis “L” and in a “B”-direction (rear side) approaching an opposite side (imaging element side/image side) to the object to be photographed. The photographing unit1is formed in a substantially rectangular prism shape. The photographing unit1generally includes a movable body3which holds optical elements such as a plurality of the lenses1a(seeFIG. 1) and a fixed diaphragm on its inner side, a magnetic drive mechanism5for moving the movable body3along an optical axis “L” direction, and a support body2on which the magnetic drive mechanism5, the movable body3and the like are mounted. The movable body3is provided with a lens holder12in a cylindrical tube shape which holds the lenses1aand the fixed diaphragm (not shown) and a coil holder13which holds the lens holder12on its inner side. Lens drive coils30sand30tstructuring the lens drive mechanism5are held on an outer peripheral side face of the coil holder13.

The support body2includes a spring holder19which holds a spring described below on an opposite side to an object side (“−Z” side), a circuit board holder16in a rectangular plate shape which positions a circuit board15on an opposite side to the object side (“−Z” side) with respect to the spring holder19, a case18in a box shape which is fitted to the spring holder19from the object side, and a spacer11in a rectangular plate shape which is disposed on an inner side of the case18. An imaging element1bis mounted on a circuit board face152of the circuit board15which is directed to the object side. Further, a filter1csuch as an infrared filter is held on the spring holder19. Incident windows11aand18afor taking light from an object to be photographed into the lenses1aare respectively formed at the centers of the spacer11and the case18. Further, windows16aand19afor guiding the incident light to the imaging element1bare formed at the centers of the circuit board holder16and the spring holder19.

The case18is made of a ferromagnetic plate such as a steel plate and functions as a yoke. Therefore, the case18structures an interlinkage magnetic field generating body together with lens drive magnets17described below for generating a magnetic field interlinking with the lens drive coils30sand30t. The interlinkage magnetic field generating body structures the lens drive mechanism5together with the lens drive coils30sand30twhich are wound around an outer peripheral face of the coil holder13.

The support body2and the movable body3are connected with each other through metal spring members14sand14twhich are disposed at separated positions in the optical axis direction. In this embodiment, the spring member14sis used on the imaging element1bside and the spring member14tis used on an object to be photographed side. Basic structures of the spring members14sand14tare similar to each other and each of the spring members14sand14tis provided with an outer peripheral side connecting part141which is held by the support body2, a circular ring-shaped inner peripheral side connecting part142which is held by the movable body3, and arm parts143having a thinner width which are connected with the outer peripheral side connecting part141and the inner peripheral side connecting part142. The outer peripheral side connecting part141of the spring member14son the imaging element1bside is held by the spring holder19and its inner peripheral side connecting part142is connected with an imaging element side end part of the coil holder13of the movable body3. The arm part143of the spring member14sis extended in a circular arc shape in a circumferential direction. The outer peripheral side connecting part141of the spring member14ton the object side is held by the spacer11and its inner peripheral side connecting part142is connected with an object side end part of the coil holder13of the movable body3. The arm part143of the spring member14tis extended in a circular arc shape in the circumferential direction while meandering in a radial direction. In this manner, the movable body3is supported by the support body2through the spring members14sand14tso as to be movable in the direction of the optical axis. Each of the spring members14sand14tis made of nonmagnetic metal such as beryllium copper or nonmagnetic SUS steel material and is formed by performing press working or etching processing using photo lithography technique on a thin plate having a certain thickness. The spring member14sis divided into two spring pieces and respective coil ends of the lens drive coils30sand30tare connected with the respective spring pieces. Further, two spring pieces of the spring member14sare connected with terminals14aand14band thus the spring member14sfunctions also as a power supply member for the lens drive coils30sand30t.

A ring-shaped magnetic piece61is held at an object side end part of the coil holder13and the position of the magnetic piece61is held at a position on the object side with respect to the lens drive magnets17. Therefore, the magnetic piece61applies an urging force in the direction of the optical axis “L” to the movable body3by an attraction force acted between the lens drive magnets17and the magnetic piece61. Accordingly, at a non-energization time (home position), the lens holder12is set stationary on the imaging element1bside by the attraction force between the lens drive magnets17and the magnetic piece61. Further, the magnetic piece61acts as a yoke and thus a leakage flux from a magnetic path structured between the lens drive magnets17and the lens drive coils30sand30tcan be reduced. The magnetic piece61may be formed in a bar shaped magnetic body or a spherical shaped magnetic body. In a case that the magnetic piece61is formed in a ring shape, when the lens holder12is to be moved in the optical axis direction, an attraction force acted between the lens drive magnets17and the magnetic piece61becomes isotropic. In addition, at the time of energization to the lens drive coils30sand30t, the magnetic piece61is moved in a direction separated from the lens drive magnets17and thus an unnecessary force pressing the lens holder12to the imaging element1bside may not act. Therefore, the lens holder12can be moved in the optical axis direction with small electric power.

In the photographing unit1in this embodiment, when viewed in the direction of the optical axis “L”, the lens1a(seeFIG. 1) is formed in a circular shape but the case18used in the support body2is formed in a rectangular box shape. Therefore, the case18is provided with a rectangular tube-shaped body part18cand an upper plate part18bformed with the incident window18ais provided on an upper face side of the rectangular tube-shaped body part18c. The lens drive magnets17are fixed to inner side face parts corresponding to the corners of a quadrangle of the rectangular tube-shaped body part18cand the lens drive magnets17are respectively comprised of a triangular prism-shaped permanent magnet. Each of four lens drive magnets17is divided into two pieces in the direction of the optical axis and is magnetized so that a magnetic pole of its inner face and a magnetic pole of its outer face are different from each other. Therefore, winding directions of the two lens drive coils30sand30taround the coil holder13are opposite to each other. The movable body3which is structured as described above is disposed on an inner side of the case18. As a result, the lens drive coils30sand30trespectively face the lens drive magnets17which are fixed to the inner face of the rectangular tube-shaped body part18cof the case18to structure the lens drive mechanism5.

In the photographing unit1structured as described above, the movable body3is normally located on the imaging element side (one side in the “Z”-axis direction) and, in this state, when an electric current is supplied to the lens drive coils30sand30tin a predetermined direction, an electro-magnetic force directing to the object side (the other side in the “Z”-axis direction) is applied to the respective lens drive coils30sand30t. Therefore, the movable body3to which the lens drive coils30sand30tare fixed begins to move to the object side (front side). In this case, an elastic force restricting movement of the movable body3is generated between the spring member14tand the front end of the movable body3and between the spring member14sand the rear end of the movable body3. Therefore, when the electro-magnetic force for moving the movable body3to the front side and the elastic force for restricting the movement of the movable body3are balanced with each other, the movable body3is stopped. In this case, when an amount of an electric current supplied to the lens drive coils30sand30tis adjusted depending on the elastic force acting on the movable body3by the spring members14sand14t, the movable body3can be stopped at a desired position.

(Structure of Optical Unit100)

FIGS. 5(a) and5(b) are cross-sectional views showing an internal structure of the optical unit100with a shake correcting function in accordance with the first embodiment of the present invention.FIG. 5(a) is a “YZ” cross-sectional view of the optical unit100andFIG. 5(b) is an “XZ” cross-sectional view of the optical unit100. InFIGS. 5(a) and5(b), only the case18, the circuit board holder16and the circuit board15of the photographing unit1are shown and other members are not shown.FIG. 6is an exploded perspective view showing the optical unit100with a shake correcting function in accordance with the first embodiment of the present invention which is viewed from an object to be photographed side.FIG. 7is an exploded perspective view showing the optical unit100with a shake correcting function in accordance with the first embodiment of the present invention which is viewed from an opposite side to an object to be photographed side.

InFIGS. 5(a) and5(b), andFIGS. 6 and 7, the optical unit100includes a fixed body200, the photographing unit1, a spring member600through which the photographing unit1is supported by the fixed body200so as to be capable of displacing, and a movable module drive mechanism500which generates a magnetic drive force for relatively displacing the photographing unit1with respect to the fixed body200between the photographing unit1and the fixed body200. An outer peripheral portion of the photographing unit1is structured of the case18which is used in the support body2in the photographing unit1.

The fixed body200is provided with an upper cover250, a spacer280and a lower cover700and the upper cover250is provided with a rectangular tube-shaped body part210which surrounds the photographing unit1and an end plate part220which closes an opening part on the object side of the rectangular tube-shaped body part210. The end plate part220is formed with a window220athrough which light from an object to be photographed is incident. In the upper cover250, an end part on the opposite side (“+Z” side) to the object side (side to which the optical axis is extended) of the rectangular tube-shaped body part210is formed to be opened. Further, cut-out portions219are formed at two positions of the rectangular tube-shaped body part210which are faced in the “Y”-axis direction. The cut-out portion219on one side “+Y” in the “Y”-axis direction is utilized when the flexible circuit board420is to be connected with terminal parts of the sheet-shaped coil550described below. Further, cut-out portions218which are utilized for engaging with the spacer280described below are formed in four faces of the rectangular tube-shaped body part210. Two of the four cut-out portions218located in the “Y”-axis direction are connected with the cut-out portion219to structure one cut-out portion. Further, a cut-out portion217connected with the cut-out portion218is formed at two positions facing in the “Y”-axis direction on the lower end side of the rectangular tube-shaped body part210. The cut-out portion217on one side “+Y” in the “Y”-axis direction is utilized for extending the flexible circuit board410to an outer side.

The spacer280is provided with a frame part281in a quadrangular shape, which is sandwiched between the rectangular tube-shaped body part210of the upper cover250and the lower cover700, columnar shaped parts283which are protruded toward an object side from corner portions of the frame part281, and engaging protruded parts285which are slightly protruded from side portions of the frame part281toward outer sides. When the upper cover250is fitted to the spacer280, the engaging protruded part285is engaged with the cut-out portion218which is cut off in a quadrangular shape in the rectangular tube-shaped body part210of the upper cover250and, as a result, positioning of the spacer280to the upper cover250is performed.

The lower cover700is a press-worked product made of a metal plate and is provided with a bottom plate part710in a substantially rectangular shape and four side plate parts720which are stood up toward an object side from an outer circumferential edge of the bottom plate part710. When the spacer280and the upper cover250are superposed on the lower cover700, the frame part281of the spacer280is sandwiched between the side plate part720and the rectangular tube-shaped body part210of the upper cover250.

The side plate part720located on one side “+Y” in the “Y”-axis direction is formed with a cut-out portion728and a part of the side plate part720is left as a plate-shaped projection729at a center part of the cut-out portion728. Further, a window-shaped cut-out portion726is formed in the side plate part720located on the other side “−Y” in the “Y”-axis direction and a part of the side plate part720is left as a crosspiece part727at a center part of the cut-out portion726. The cut-out portion728is, as described below, utilized to extend the flexible circuit board410to an outer side and the cut-out portion726is utilized to prevent a folded-back portion413from interfering with the side plate part720of the lower cover700.

A bottom plate part710of the lower cover700is formed with a hole711at its center position and recessed parts716and717which are recessed in a rectangular shape are formed at a position adjacent to the hole711on the other side “−X” in the “X”-axis direction and a position adjacent to the hole711on the other side in the “Y”-axis direction. As described below, inner faces of the bottom parts716aand717aof the recessed parts716and717are a substantially mirror surface and the bottom parts716aand717aare utilized as reflection faces for a first photo reflector580and a second photo reflector590which are mounted on a circuit board face151of the circuit board15on an opposite side to an object side.

The lower cover700is formed of a metal member which is non-magnetized by heat treatment. Specifically, the lower cover700is a metal member in which metal material such as “SUS 304” is performed with a bending work or a drawing work in a predetermined shape. When a bending work or a drawing work is performed on “SUS 304” or the like, a part of austenite is transferred to martensite to provide with a magnetic property. However, in this embodiment, heat treatment is performed on the lower cover700after a bending work or a drawing work. Therefore, when the optical unit100is to be assembled, attraction between the permanent magnets520and the lower cover700is prevented. Further, when heat treatment is performed on metal material such as “SUS 304”, its reflectivity becomes higher and thus the lower cover700is provided with a sufficient reflectivity for utilizing as a reflection surface for the first photo reflector580and the second photo reflector590.

(Structure of Swing Support Point)

On one side “+Z” in the “Z”-axis (opposite side to the object side) with respect to the photographing unit1, a swing support point180when the photographing unit1is to be swung is provided between the photographing unit1and the lower cover700of the fixed body200. The photographing unit1is urged toward the lower cover700by the spring member600through the swing support point180. In this embodiment, the swing support point180is structured of a steel ball181, which is positioned by a hole711formed in the bottom plate part710of the lower cover700, and a support plate183which is fixed to a circuit board face151of the circuit board15. The photographing unit1is capable of swinging with an abutted position of the steel ball181with the support plate183as a swing center.

(Structure of Spring Member600)

The spring member600is a plate-shaped spring member which is provided with a fixed side connecting part620sandwiched between the side plate part720of the lower cover700and the frame part281of the spacer280in the fixed body200, a movable side connecting part610connected with the photographing unit1, and a plurality of arm parts630which are extended between the movable side connecting part610and the fixed side connecting part620. Both ends of the arm part630are respectively connected with the movable side connecting part610and the fixed side connecting part620. In this embodiment, the movable side connecting part610of the spring member600is fixed to a stepped part168which is formed on an outer peripheral side of a circuit board holder16on a rear end side of the photographing unit1. The spring member600is made of nonmagnetic metal such as beryllium copper or nonmagnetic SUS steel material and is formed by performing a press working or etching processing using a photo lithography technique on a thin plate having a certain thickness.

In this embodiment, when the photographing unit1is disposed on an object side with respect to the steel ball181in a state that the fixed side connecting part620of the spring member600is sandwiched between the side plate part720of the lower cover700and the frame part281of the spacer280in the fixed body200, the photographing unit1becomes in a state that the photographing unit1is pushed up to an object side by the steel ball181. Therefore, the movable side connecting part610of the spring member600is set in a state that the movable side connecting part610is pushed to the object side with respect to the fixed side connecting part620and thus the arm parts630of the spring member600urges the photographing unit1to an opposite side to the object side. Accordingly, the photographing unit1is set in a state that the photographing unit1is urged toward the bottom plate part710of the lower cover700through the swing support point180by the spring member600and thus the photographing unit1is set in a supported state by the fixed body200so as to be capable of being swung through the swing support point180.

(Structure of Shake Correction Drive Mechanism)

As shown inFIG. 5(a) throughFIG. 7, in the optical unit100in this embodiment, the shake correction drive mechanism500is structured of a coil part560and a permanent magnet520for generating a magnetic field interlinking with the coil part560. Specifically, four outer faces18e,18f,18gand18hof the rectangular tube-shaped body part18cof the case18of the photographing unit1are fixed with a flat plate-shaped permanent magnet520and the coil part560is disposed on inner faces211,212,213and214of the rectangular tube-shaped body part210of the upper cover250. The permanent magnet520is magnetized so that the pole of its outer side and the pole of its inner side are different from each other. Further, the permanent magnet520is comprised of two magnet pieces disposed in the optical axis “L” direction and the magnet pieces are magnetized so that the poles of faces oppositely disposed to the coil part560are different from each other in the optical axis direction. Further, the coil part560is formed in a quadrangular frame shape and its upper and lower long side portions are utilized as an effective side.

In the permanent magnets520and the coil parts560, the permanent magnets520and the coil parts560disposed at two positions so as to interpose the photographing unit1from both sides in the “Y”-axis direction structure a “Y”-side shake correction drive mechanism500yand, as shown by the arrows “X1” and “X2” inFIG. 5(a), the photographing unit1is swung with the axial line “X0” extending in the “X”-axis direction passing through the swing support point180as a swing center. Further, the permanent magnets520and the coil parts560disposed at two positions so as to interpose the photographing unit1from both sides in the “X”-axis direction structure an “X”-side shake correction drive mechanism500xand, as shown by the arrows “Y1” and “Y2” inFIG. 5(b), the photographing unit1is swung with the axial line “Y0” extending in the “Y”-axis direction passing through the swing support point180as a swing center.

In order to structure the “Y”-side shake correction drive mechanism500yand the “X”-side shake correction drive mechanism500x, in this embodiment, a sheet-shaped coil550is used so as to be extended along the four inner faces211,212,213and214of the upper cover250and four coil parts560are integrally formed in the sheet-shaped coil550with a predetermined distance therebetween. Further, when developed, the sheet-shaped coil550is provided with a shape extended in a belt shape and is fixed to the four inner faces211,212,213and214of the upper cover250by a method such as surface bonding in a state that the sheet-shaped coil550is bent along the inner faces211,212,213and214of the upper cover250. In this state, both end parts551and552of the sheet-shaped coil550are brought close to each other through a slit555.

The sheet-shaped coil550is structured so that the coil part560made of a minute copper wiring line is formed on a printed circuit board by utilizing an electric conduction wiring technique. A plurality of copper wiring layers (coil part560) is formed in multi-layer through an insulation film. Further, the surface of the copper wiring line (coil part560) is covered with an insulation film. For example, an FP coil (fine pattern coil (registered mark)) made by ASAHI KASEI ELECTRONICS CO., LTD. may be used as the sheet-shaped coil550.

In this embodiment, an end part551of the sheet-shaped coil550is formed with a protruded part553which is protruded in a rectangular shape to an opposite side to the object side and the protruded part553is formed with a plurality of terminal parts565which are made of electrically conducting layers extended from the four coil parts560. In this embodiment, the terminal parts565are disposed on an outer side of the sheet-shaped coil550which is opposite to the inner side facing the permanent magnet520. Further, as shown inFIGS. 2(a) and2(b), andFIGS. 6 and 7, the cut-out part219is formed in the portion of the upper cover250which is overlapped with the terminal parts565. Therefore, since the terminal parts565(protruded part553) of the sheet-shaped coil550are exposed to the outer side, the sheet-shaped coil550and an end part425of the flexible circuit board420which is bent toward the direction of the optical axis “L” are electrically connected with each other in the cut-out part219by soldering or the like.

In the optical unit100which is structured as described above, the photographing unit1is supported by the fixed body200in a state that the photographing unit1is capable of swinging through the swing support point180. Therefore, when a large force is applied from the outside to swing the photographing unit1largely, the arm parts630of the spring member600may be plastically deformed. In this embodiment, the sheet-shaped coil550and the permanent magnet520are faced each other through a narrow gap space. Further, in a case of the sheet-shaped coil550, different from an air-core coil, a wound coil is not loosened even when the coil is abutted with the permanent magnet520. Therefore, in the optical unit100in this embodiment, moving ranges of the photographing unit1in the “X”-axis direction and the “Y”-axis direction intersecting with the optical axis “L” are restricted by abutting of the sheet-shaped coil550with the permanent magnet520and thus another stopper mechanism for preventing the swing of the photographing unit1is not provided.

Further, in this embodiment, since the sheet-shaped coil550is used, in comparison with a case that a discrete air-core coil is separately used, a distance between the photographing unit1and the fixed body200can be narrowed and thus the size of the optical unit100can be reduced. Further, in a case of the sheet-shaped coil550, a plurality of coil parts560is integrally formed with the terminal parts565and thus, even when the coil parts560are disposed at plural positions around the optical axis “L”, it is sufficient that the sheet-shaped coil550is extended around the optical axis “L”. Therefore, different from a case that a discrete air-core coil is separately used, discrete air-core coils are not required to be disposed at plural positions around the optical axis “L” and the respective air-core coils are not required to be electrically connected and thus, according to this embodiment, assembly man-hours are reduced. Further, the terminal parts565of the sheet-shaped coil550are disposed so as to face the outer side which is an opposite side to a side facing the permanent magnet520and thus electrical connection with the coil parts560, in other words, connection of the flexible circuit board420with the terminal parts565can be performed easily.

In the optical unit100in this embodiment, when the optical device1000shown inFIG. 1is shaken, the shake is detected by a gyroscope and the host control section controls the shake correction drive mechanism500based on a detection result by the gyroscope. In other words, a drive current for cancelling the shake which is detected by the gyroscope is supplied to the coil parts560of the sheet-shaped coil body550through the flexible circuit board410and the flexible circuit board420. As a result, the “X”-side shake correction drive mechanism500xswings the photographing unit1around the “Y”-axis with the swing support point180as a swing center. Further, the “Y”-side shake correction drive mechanism500yswings the photographing unit1around the “X”-axis with the swing support point180as the swing center. Further, when the swing around the “X”-axis and the swing around the “Y”-axis of the photographing unit1are combined with each other, the photographing unit1is displaced over the entire “XY” plane. Accordingly, all shakes occurred in the optical unit100can be corrected surely. When the photographing unit1is to be driven, the displacement of the photographing unit1is monitored by the first photo reflector580and the second photo reflector590as described below with reference toFIGS. 8(a),8(b),9(a),9(b) and9(c).

(Structure of Flexible Circuit Board410)

In the optical unit100in this embodiment, one end part of the flexible circuit board410is connected with the circuit board15of the photographing unit1. In a case that the photographing unit1is to be swung, when the flexible circuit board410applies a load to the photographing unit1, an appropriate swing of the photographing unit1may be obstructed.

The main body portion415of the flexible circuit board410which is located on an outer side of the optical unit100is formed in a wide width so as to be capable of mounting a connector490and being connected with the flexible circuit board420. However, in order to prevent the above-mentioned problem, a portion of the flexible circuit board410which is located on an inner side of the optical unit100is formed in two strip-shaped portions411whose width dimension is narrower than the main body portion415. Further, the strip-shaped portion411is extended from one side “+Y” in the “Y”-axis direction toward the other side “−Y” and then, the strip-shaped portion411is folded back toward the one side “+Y” and, after that, an end part of the strip-shaped portion411is folded back along an edge of the circuit board15so as to be faced toward a circuit board face on the object side of the circuit board15and fixed. Therefore, since the flexible circuit board410is provided with the folded-back portion413between the main body portion415disposed on the outer side and the portion fixed to the circuit board15and thus its dimension is long. Accordingly, the strip-shaped portion of the flexible circuit board410is capable of following a shake of the photographing unit1smoothly and thus a large load is not applied to the photographing unit1.

Further, the strip-shaped portion411of the flexible circuit board410is formed at a midway portion in its length direction with a slit418which is extended along an extended direction (“Y”-axis direction) of the strip-shaped portion411and the midway portion of the strip-shaped portion411is divided into two thinner width portions416and417in a widthwise direction. Therefore, the rigidity of the strip-shaped portion411is relaxed. Accordingly, the strip-shaped portion of the flexible circuit board410is capable of following a shake of the photographing unit1smoothly and thus a large load is not applied to the photographing unit1.

In this embodiment, the strip-shaped portion411of the flexible circuit board420is superposed on the photographing unit1in the optical axis “L” direction. However, the portion of the strip-shaped portion411which is superposed on the swing support point180is formed with a circular hole414connected with the slit418. Therefore, even when the strip-shaped portion411of the flexible circuit board420is disposed at a position superposed on the photographing unit1in the optical axis “L” direction, the swing support point180is provided without a problem.

Further, in the side plate part720of the lower cover700, the side plate part720located on one side “+Y” in the “Y”-axis direction is formed with the cut-out portion728for extending the strip-shaped portion411of the flexible circuit board420and a part of the side plate part720is left as a plate-shaped projection729at the center part of the cut-out portion728. However, a hole419in an elliptic shape is formed in a portion of the strip-shaped portion411of the flexible circuit board420which is superposed on the plate-shaped projection729. Therefore, when the strip-shaped portion411of the flexible circuit board420is extended to an outer side through the cut-out portion728of the side plate part720, the plate-shaped projection729is inserted into the hole419and thus the strip-shaped portion411of the flexible circuit board420is extended to the outer side without a problem. Further, since the plate-shaped projection729is fitted to the hole419, positioning of the strip-shaped portion411of the flexible circuit board420can be performed.

In addition, in the side plate part720of the lower cover700, the side plate part720located on the other side “−Y” in the “Y”-axis direction is formed with the cut-out portion726in a window shape. Therefore, even when the folded-back portion413of the flexible circuit board410is located in the vicinity of the side plate part720, the folded-back portion413and the side plate part720are not interfered with each other. Accordingly, when the photographing unit1is swung, an unnecessary load due to interference of the folded-back portion413with the side plate part720is not applied to the photographing unit1.

In addition, the folded-back portion413of the flexible circuit board410is located at the same height position as the swing center of the photographing unit1in the swing support point180(abutting position of the steel ball181with the support plate183). Therefore, when the photographing unit1is swung, the displacement of the strip-shaped portion411is restrained small. Accordingly, affection of the flexible circuit board410applied to the photographing unit1is reduced and thus the photographing unit1is swung with a high degree of accuracy.

(Structure of Photo Reflector)

FIGS. 8(a) and8(b) are explanatory views showing photo reflectors which are provided in the optical unit100with a shake correcting function in accordance with the first embodiment of the present invention.FIG. 8(a) is an exploded perspective view showing an opposite side portion of the optical unit100to the object side andFIG. 8(b) is an explanatory view showing a positional relationship between the photo reflectors and reflection faces.FIGS. 9(a),9(b) and9(c) are explanatory views showing a positional relationship between photo reflectors and a flexible circuit board in the optical unit100with a shake correcting function in accordance with the first embodiment of the present invention.FIG. 9(a) is a bottom view showing a positional relationship between reflection parts of the lower cover700and the swing support point,FIG. 9(b) is a bottom view showing a positional relationship between the strip-shaped portion411of the flexible circuit board410and a photo reflector (a first photo reflector580and a second photo reflector590), andFIG. 9(c) is a bottom view showing a positional relationship between the photo reflector and the swing support point.FIG. 10is an explanatory view showing a layout of two photo reflectors in the optical unit100with a shake correcting function in accordance with the first embodiment of the present invention. InFIGS. 9(b) and9(c), a light emission center and a light reception center of a photo reflector is indicated with a small circle and, inFIG. 10, a light emission center and a light reception center of a photo reflector is indicated with a “+” mark.

As shown inFIG. 5(a) throughFIG. 9(c), in the optical unit100with a shake correcting function in this embodiment, the swing support point180is structured between the circuit board15which structures the bottom part of the photographing unit1and the lower cover700of the fixed body200and a first photo reflector580and a second photo reflector590are mounted on the circuit board face151of the circuit board15facing the lower cover700. Further, two recessed parts716and717are formed in the bottom plate part710of the lower cover700and inner faces of the bottom parts716aand717aof the recessed parts716and717are a first reflection part716cand a second reflection part717cfor the first photo reflector580and the second photo reflector590.

As shown inFIGS. 9(a),9(b) and9(c) andFIG. 10, each of the first photo reflector580and the second photo reflector590is formed in a rectangular planar shape when viewed in the optical axis “L” direction and, as shown inFIG. 10, is provided with short sides581,582,591and592and long sides583,584,593and594. Further, the first photo reflector580and the second photo reflector590are respectively provided with light emitting parts586and596at end parts on one side in the longitudinal direction and light receiving parts587and597at end parts on the other side in the longitudinal direction. Further, in the first photo reflector580and the second photo reflector590, light intercepting parts585and595are formed between the light emitting parts586and596and the light receiving parts587and597.

In this embodiment, the first photo reflector580is disposed at a position superposing the axial line “X0” described with reference toFIG. 5(b) in the optical axis “L” direction and the light emission center and the light reception center of the first photo reflector580are disposed at a linear symmetrical position with respect to the axial line “X0” in the direction perpendicular to the optical axis “L”. Further, the second photo reflector590is disposed at a position superposing the axial line “Y0” described with reference toFIG. 5(a) in the optical axis “L” direction and the light emission center and the light reception center of the second photo reflector590are superposed on the axial line “Y0” in the optical axis “L” direction.

Further, the first photo reflector580and the second photo reflector590are disposed so that the long sides583,584,593and594are extended in the “Y”-axis direction and are parallel to the extended direction of the strip-shaped portion411of the flexible circuit board410. Therefore, the short sides581,582,591and592of the first photo reflector580and the second photo reflector590are extended in the widthwise direction of the flexible circuit board410. Therefore, even when the second photo reflector590is disposed at a position superposing on the slit418of the flexible circuit board410so that the second photo reflector590and the flexible circuit board410are not superposed on each other in the optical axis “L” direction, the width dimension of the slit418is not required to be increased. Further, in the strip-shaped portion411of the flexible circuit board410, even in a case that a cut-out portion416ais formed on an outer side edge portion of the thinner width portion416and the first photo reflector580is disposed at a position superposing on the cut-out portion416aso that the first photo reflector580and the flexible circuit board410are disposed so as not to superpose on each other in the optical axis “L” direction, a width dimension of the cut-out portion416acan be narrowed. Therefore, even when the strip-shaped portion411of the flexible circuit board410is extended in the “Y”-axis direction so as to avoid the position superposing on the first photo reflector580and the second photo reflector590in the optical axis “L” direction between the bottom part (circuit board15) of the photographing unit1and the lower cover700of the fixed body200, the width dimension of the strip-shaped portion411is comparatively large.

Further, the first photo reflector580and the second photo reflector590are disposed so that their light emitting parts586and596are located on one side “+Y” in the “Y”-axis direction and their light receiving parts587and597are located on the other side “−Y” in the “Y”-axis direction.

In the first photo reflector580and the second photo reflector590structured as described above, in a state that the circuit board15and the bottom plate part710of the lower cover700are parallel to each other, as shown inFIG. 8(b), light emitted from the light emitting part586of the photo reflector580is reflected by the first reflection part716cto be received by the light receiving part587of the first photo reflector580with a high intensity and light emitted from the light emitting part596of the second photo reflector590is reflected by the second reflection part717cto be received by the light receiving part597of the second photo reflector590with a high intensity. On the other hand, in a state that the circuit board15and the bottom plate part710of the lower cover700are not parallel to each other, light-receiving intensity in the light receiving part587of the first photo reflector580and light-receiving intensity in the light receiving part597of the second photo reflector590are lowered. Further, the light-receiving intensity in the light receiving part587of the first photo reflector580and the light-receiving intensity in the light receiving part597of the second photo reflector590are varied according to a direction of inclination of the photographing unit1with respect to the fixed body200. Therefore, inclination of the photographing unit1is detected when the photographing unit1is swung around the axial lines “X0” and “Y0” for correcting a shake of hand in the optical unit1. Accordingly, the swing of the photographing unit1by the shake correction drive mechanism500is appropriately performed by utilizing the detection result.

In this embodiment, the first photo reflector580is disposed at a position superposing on the axial line “X0” in the optical axis “L” direction and the second photo reflector590is disposed at a position superposing on the axial line “Y0” in the optical axis “L” direction. Therefore, displacement in the “X”-axis direction of the photographing unit1is monitored by the detection result of the first photo reflector580when the photographing unit1is turned around the axial line “Y0”. Further, displacement in the “Y”-axis direction of the photographing unit1is monitored by the detection result of the second photo reflector590when the photographing unit1is turned around the axial line “X0”. Therefore, displacement of the photographing unit1when turned around the axial line “X0” and displacement of the photographing unit1when turned around the axial line “Y0” are independently monitored and thus the turning around the axial line “X0” of the photographing unit1and the turning around the axial line “Y0” are controlled independently.

Principal Effects in this Embodiment

As described above, in the optical unit100in this embodiment, the shake correction drive mechanism500for swinging the photographing unit1as a movable module is provided and thus, when a shake such as a hand shake occurs in the optical unit100, the photographing unit1can be swung to cancel the shake. Therefore, even when the optical unit100is shaken, inclination of the optical axis “L” can be corrected.

Further, in two axial lines “X0” and “Y0” when the photographing unit1is to be swung, the first photo reflector580is provided at the position superposing on the axial line “X0” in the optical axis “L” direction and the second photo reflector590is provided at the position superposing on the axial line “Y0” in the optical axis “L” direction. Therefore, shakes of the photographing unit1for the two axial lines “X0” and “Y0” are independently monitored and controlled by the first photo reflector580and the second photo reflector590.

In addition, the shake correction drive mechanism500is provided between the outer peripheral face of the photographing unit1and the fixed body200(upper cover250), and the first photo reflector580and the second photo reflector590are provided by utilizing a space between the bottom part (circuit board15) of the photographing unit1and the fixed body200(lower cover700) in which the swing support point180is provided. Therefore, even when the photo reflector (the first photo reflector580and the second photo reflector590), the swing support point180and the shake correction drive mechanism500are provided for the photographing unit1, the increase of size in the optical axis “L” direction and the direction intersecting the optical axis direction (“X”-axis direction and “Y”-axis direction) can be restrained.

Further, the flexible circuit board410is extended in the “Y”-axis direction between the bottom part of the photographing unit1and the fixed body200so as not to superpose on the first photo reflector580and the second photo reflector590in the optical axis “L” direction. However, the extended directions of the long sides583,584,593and594of the first photo reflector580and the second photo reflector590and the extended direction of the flexible circuit board410are parallel to each other. Therefore, the regions occupied by the first photo reflector580and the second photo reflector590are narrow in the widthwise direction (“X”-axis direction) of the flexible circuit board410and thus the flexible circuit board410are extended in a wide width dimension. Accordingly, a number of wiring patterns can be provided in the strip-shaped portion411.

Further, the first photo reflector580and the second photo reflector590are provided in the bottom part of the photographing unit1and the first reflection part716cand the second reflection part717cfor the first photo reflector580and the second photo reflector590are formed of inner bottom faces of the recessed parts716and717provided in the bottom plate part710of the lower cover700which face the bottom part of the photographing unit1. According to this structure, the first reflection part716cand the second reflection part717care recessed from their surrounding portions in a direction away from the bottom part of the photographing unit1. Therefore, even in a case that a sufficient distance is required to secure between the first photo reflector580and the first reflection part716cand between the second photo reflector590and the second reflection part717c, a portion close to the bottom part of the photographing unit1can be provided in the lower cover700and thus the swing support point180can be provided at this close portion. Accordingly, the region where the swing support point180occupies is narrowed. In other words, when the lower cover700and the bottom part of the photographing unit1are set to be close to each other, a steel ball181having a small diameter may be used and thus the region where the swing support point180occupies can be narrowed. Accordingly, a space for disposing the first photo reflector580and the second photo reflector590can be secured between the bottom part of the photographing unit1and the lower cover700. In accordance with an embodiment of the present invention, even in a case that a projection is utilized to structure the swing support point180instead of using the steel ball181, when the lower cover700and the bottom part of the photographing unit1are set close to each other, the height dimension of the projection can be made small and thus the region where the projection occupies is narrowed. Therefore, a space for disposing the first photo reflector580and the second photo reflector590can be secured between the bottom part of the photographing unit1and the lower cover700.

Further, the lower cover700is a metal member which is structured of metal material such as SUS304 on which a bending work or a drawing work are performed in a predetermined shape and is non-magnetized by heat treatment. Therefore, when the optical unit100is to be assembled, attraction and the like between the permanent magnet520and the lower cover700can be prevented. Further, when heat treatment is performed on metal material such as SUS304 and the like, its reflectivity becomes higher and thus the lower cover700is provided with a sufficient reflectivity for utilizing as a reflection face for the first photo reflector580and the second photo reflector590. Therefore, reflection tape is not required to put on the lower cover700for providing the first reflection part716cand the second reflection part717cfor the first photo reflector580and the second photo reflector590.

In addition, the bottom part of the photographing unit1is the circuit board15whose circuit board face151is mounted with the first photo reflector580and the second photo reflector590and the imaging element1bis mounted on the circuit board face152on the opposite side of the circuit board15. Therefore, the first photo reflector580and the second photo reflector590are mounted on the same circuit board15for the imaging element1band thus the number of part items is reduced.

Second Embodiment

FIG. 11is an explanatory view showing a layout of two photo reflectors in an optical unit100with a shake correcting function in accordance with a second embodiment of the present invention. A basic structure in the second embodiment is similar to the first embodiment and thus the common portions are shown with the same reference sign and their descriptions are omitted. As shown inFIG. 11, also in the optical unit100with a shake correcting function in this embodiment, similarly to the first embodiment, the first photo reflector580is disposed at a position superposing on the axial line “X0” in the optical axis “L” direction and the second photo reflector590is disposed at a position superposing on the axial line “Y0” in the optical axis “L” direction. Further, the first photo reflector580and the second photo reflector590are disposed so that their long sides583,584,593and594are extended in the “Y”-axis direction and are parallel to the extended direction of the strip-shaped portion411of the flexible circuit board410as described with reference toFIGS. 6 through 9(c). Further, the first photo reflector580and the second photo reflector590are disposed so that their light emitting parts586and596are located on one side “+Y” in the “Y”-axis direction and their light receiving parts587and597are located on the other side “−Y” in the “Y”-axis direction.

In the first photo reflector580and the second photo reflector590structured as described above, the light emitted from the light emitting part596of the second photo reflector590may be incident on the first photo reflector580through a space between the first photo reflector580and the second photo reflector590. Further, in a case that the circuit board15has translucency like a glass-epoxy circuit board, the light emitted from the light emitting part596of the second photo reflector590may be incident on the first photo reflector580through the circuit board15.

In order to prevent this problem, in this embodiment, in four side face parts of the first photo reflector580disposed in directions intersecting the optical axis “L” direction, light shielding layers588and589are provided on two side faces which face the second photo reflector590. Further, in four side face parts of the second photo reflector590disposed in directions intersecting the optical axis “L” direction, light shielding layers598and599are provided on two side faces which face the first photo reflector580. Specifically, the light shielding layers588and589are provided on the side faces corresponding to the short side582and the long side583of the first photo reflector580which are located on the second photo reflector590side and the light shielding layers598and599are provided on the side faces corresponding to the short side591and the long side594of the second photo reflector590which are located on the first photo reflector580side. Therefore, the light emitted from the light emitting part596of the second photo reflector590is not incident on the light receiving part587of the first photo reflector580.

In this embodiment, a separated distance between the light emitting part586of the first photo reflector580and the light receiving part597of the second photo reflector590is longer than the separated distance between the light receiving part587of the first photo reflector580and the light emitting part596of the second photo reflector590. Therefore, there is a little possibility that the light emitted from the light emitting part586of the first photo reflector580is incident on the light receiving part597of the second photo reflector590. However, in this embodiment, the light shielding layers588and589are formed on the entire two side faces of the first photo reflector580which face the second photo reflector590and the light shielding layers598and599are provided on the entire two side faces of the second photo reflector590which face the first photo reflector580. Therefore, the light emitted from the light emitting part586of the first photo reflector580is surely prevented from being incident on the light receiving part597of the second photo reflector590.

As a result, according to this embodiment, a cross talk does not occur between the first photo reflector580and the second photo reflector590and thus displacement of the photographing unit1when turned around the axial line “X0” and displacement of the photographing unit1when turned around the axial line “Y0” can be monitored surely.

Third Embodiment

FIGS. 12(a) and12(b) are explanatory views showing a layout of two photo reflectors in an optical unit100with a shake correcting function in accordance with a third embodiment of the present invention.FIG. 12(a) is an explanatory view showing an embodiment where respective light emitting parts are set close to each other andFIG. 12(b) is an explanatory view showing an embodiment where respective light receiving parts are set close to each other. A basic structure in the third embodiment is similar to the first embodiment and thus the common portions are shown with the same reference sign and their descriptions are omitted. As shown inFIG. 12(a), also in the optical unit100with a shake correcting function in this embodiment, similarly to the first embodiment, the first photo reflector580is disposed at a position superposing on the axial line “X0” in the optical axis “L” direction and the second photo reflector590is disposed at a position superposing on the axial line “Y0” in the optical axis “L” direction. Further, the first photo reflector580and the second photo reflector590are disposed so that their long sides583,584,593and594are extended in the “Y”-axis direction and are parallel to the extended direction of the strip-shaped portion411of the flexible circuit board410as described with reference toFIGS. 6 through 9(c).

In this embodiment, the first photo reflector580and the second photo reflector590are disposed so that the light emitting parts586and596are set close to each other and the light receiving parts587and597are set apart from each other. In other words, the light emitting part586of the first photo reflector580is disposed on a side where the second photo reflector590is located and the light emitting part596of the second photo reflector590is disposed on a side where the first photo reflector580is located. Further, the light receiving part587of the first photo reflector580is disposed on an opposite side with respect to the second photo reflector590and the light receiving part597of the second photo reflector590is disposed on an opposite side with respect to the first photo reflector580.

Also in the first photo reflector580and the second photo reflector590structured as described above, there is a possibility that the light emitted from the light emitting part596of the second photo reflector590is incident on the first photo reflector580and the light emitted from the light emitting part596of the second photo reflector590is incident on the first photo reflector580. However, in this embodiment, the first photo reflector580and the second photo reflector590are disposed so that the light emitting parts586and596are set close to each other and the light receiving parts587and597are set away from each other. Therefore, in this embodiment, in comparison with the embodiment described with reference toFIG. 10, a distance from the light emitting part596of the second photo reflector590to the light receiving part587of the first photo reflector580is long. Accordingly, even when the light emitted from the light emitting part586of the first photo reflector580is directed toward the second photo reflector590as shown by the arrow “S1”, the light is hard and difficult to be incident on the light receiving part597of the second photo reflector590. Further, even when the light emitted from the light emitting part596of the second photo reflector590is directed toward the first photo reflector580as shown by the arrow “S2”, the light is hard and difficult to be incident on the light receiving part587of the first photo reflector580. Accordingly, a cross talk does not occur between the first photo reflector580and the second photo reflector590and thus displacement of the photographing unit1when turned around the axial line “X0” and displacement of the photographing unit1when turned around the axial line “Y0” can be monitored surely.

In accordance with an embodiment of the present invention, contrary to the structure shown inFIG. 12(a), as shown inFIG. 12(b), it may be structured that the light receiving parts587and597of the first photo reflector580and the second photo reflector590are set close to each other and the light emitting parts586and596are set apart from each other. Also in this case, similar effects to the embodiment shown inFIG. 12(a) can be obtained.

Fourth Embodiment

FIGS. 13(a) and13(b) are explanatory views showing a layout of two photo reflectors in an optical unit100with a shake correcting function in accordance with a fourth embodiment of the present invention.FIG. 13(a) is an explanatory view showing an embodiment where respective light emitting parts are set close to each other andFIG. 13(b) is an explanatory view showing an embodiment where respective light receiving parts are set close to each other. A basic structure in the fourth embodiment is similar to the first embodiment and thus the common portions are shown with the same reference sign and their descriptions are omitted. As shown inFIG. 13(a), also in the optical unit100with a shake correcting function in this embodiment, similarly to the first embodiment, the first photo reflector580is disposed at a position superposing on the axial line “X0” in the optical axis “L” direction and the second photo reflector590is disposed at a position superposing on the axial line “Y0” in the optical axis “L” direction. Further, the first photo reflector580and the second photo reflector590are disposed so that their long sides583,584,593and594are extended in the “Y”-axis direction and are parallel to the extended direction of the strip-shaped portion411of the flexible circuit board410as described with reference toFIGS. 6 through 9(c).

In the embodiment shown inFIG. 13(a), similarly to the third embodiment, the first photo reflector580and the second photo reflector590are disposed so that the light emitting parts586and596are set close to each other and the light receiving parts587and597are set apart from each other.

Further, in this embodiment, similarly to the second embodiment, in four side face parts of the first photo reflector580, two side faces located on a side which face the second photo reflector590are provided with light shielding layers588and589and, in four side face parts of the second photo reflector590, two side faces located on a side which face the first photo reflector580are provided with light shielding layers598and599. Therefore, the light emitted from the light emitting part586of the first photo reflector580is not incident on the light receiving part597of the second photo reflector590. Further, the light emitted from the light emitting part596of the second photo reflector590is not incident on the light receiving part587of the first photo reflector580. Accordingly, a cross talk does not occur between the first photo reflector580and the second photo reflector590and thus displacement of the photographing unit1when turned around the axial line “X0” and displacement of the photographing unit1when turned around the axial line “Y0” can be monitored surely.

Further, in this embodiment, different from the second embodiment, the positions of the light shielding layers588,589,598and599in the first photo reflector580and the second photo reflector590are set in a point symmetrical relationship. Therefore, a photo reflector having the same structure can be used for the first photo reflector580and the second photo reflector590and thus the photo reflector can be used in common.

Contrary to the structure shown inFIG. 13(a), as shown inFIG. 13(b), it may be structured that the light receiving parts587and597of the first photo reflector580and the second photo reflector590are set close to each other and the light emitting parts586and596are set apart from each other. Also in this case, similar effects to the embodiment shown inFIG. 13(a) can be obtained.

(Modified Examples of First Reflection Part716cand Second Reflection Part717c)

In the embodiment described above, the first reflection part716cand the second reflection part717cfor the first photo reflector580and the second photo reflector590are formed of the inner bottom faces of the recessed parts716and717which are provided in the bottom plate part710of the lower cover700. However, it may be structured that the first reflection part and the second reflection part are formed in the same plane as the surrounding portion around the first reflection part and the surrounding portion around the second reflection part of the lower cover700. Also in the case having this structure, in comparison with a case that the first reflection part and the second reflection part are protruded toward the bottom part of the photographing unit1, a portion close to the bottom part of the photographing unit1can be provided in the lower cover700and the swing support point180can be provided in the close portion. Therefore, the region where the swing support point180occupies is narrowed and thus a space for disposing the first photo reflector580and the second photo reflector590is secured.

Other Embodiments

In the embodiment shown inFIG. 11andFIGS. 13(a) and13(b), in order to prevent a cross talk between the first photo reflector580and the second photo reflector590, the light shielding layer is provided on two side faces located on a side facing the second photo reflector590in four side face parts of the first photo reflector580and the light shielding layers are provided on two side faces located on a side facing the first photo reflector580in four side face parts of the second photo reflector590. However, the light shielding layer may be provided all of four side face parts of the first photo reflector580and the second photo reflector590.

Further, in the embodiment shown inFIG. 11andFIGS. 13(a) and13(b), the light shielding layer is provided on the side faces of both of the first photo reflector580and the second photo reflector590. However, in order to prevent a cross talk between the first photo reflector580and the second photo reflector590, the light shielding layer may be provided on only the side face parts of one of the first photo reflector580and the second photo reflector590.

In the embodiments described above, the present invention is, as an example, applied to the optical unit100which is used in a cell phone with a camera. However, at least an embodiment of the present invention may be applied to the optical unit100which is used in a thin type digital camera or the like. Further, in the embodiment described above, the lens drive mechanism5which magnetically drives the movable body3including the photographing unit1having the lens1aand the imaging element1bin the optical axis direction is supported on the support body2. However, at least an embodiment of the present invention may be applied to a fixed focus type optical unit in which the lens drive mechanism5is not mounted on the photographing unit1.

In addition, other than a cell phone, a digital camera and the like, the optical unit100with a shake correcting function to which at least an embodiment of the present invention is applied may be fixed in an apparatus such as a refrigerator in which vibration is occurred in a certain interval and mounted so as to be capable of being remote controlled. According to the apparatus, a service can be provided in which information in the inside of the refrigerator is obtained at a visit place, for example, at the time of shopping. According to this service, the camera system is provided with an attitude stabilizing device and thus a stable image can be transmitted even when vibration may occur in the refrigerator. Further, this device may be fixed to a device such as a bag, a satchel or a cap of a child and a student which is carried at a time of commuting or attending school. In this case, states of surroundings are photographed at a constant interval and, when the image is transmitted to a predetermined server, the parent or the like watches the image at a remote place to secure security of the child. In this application, without conscious of a camera, a clear image is photographed even when vibration occurs at the time of moving. Further, when a GPS is mounted in addition to a camera module, the position of a target person can be obtained simultaneously and thus, when an accident occurs, its position and situation can be confirmed immediately. In addition, when the optical unit100with a shake correcting function to which at least an embodiment of the present invention is applied is mounted at a position which is capable of photographing toward a front side in a car, it can be used as a drive recorder. Further, it may be structured that the optical unit100with a shake correcting function to which at least an embodiment of the present invention is applied is mounted at a position which is capable of photographing toward a front side in a car and a front side image is photographed automatically at a constant interval and is automatically transmitted to a predetermined server. Further, when this image is distributed while interlocking with traffic jam information in the VICS (Vehicle Information and Communication System) of a car navigation system, the situation of a traffic jam can be provided further in detail. According to this service, similarly to a drive recorder mounted on a car, the situation when an accident has occurred can be recorded by a third person of passer-by without intention to utilize an inspection of the situation. Further, a clear image can be acquired without affected by vibration of a car. In a case of the application, when a power supply is turned on, a command signal is outputted to the control section and the shake control is started on the basis of the command signal.

Further, the optical unit100with a shake correcting function to which at least an embodiment of the present invention is applied may be applied to shake correction of an optical device from which a light beam is emitted such as a laser beam pointer, a portable or on-vehicle projection display device and direct viewing type display device. Further, in an observation system with a high magnification such as an astronomical telescope system or a binocular system, the optical unit100may be used to observe without using an auxiliary locking device such as three-legged supports. In addition, when at least an embodiment of the present invention is applied to a rifle or a turret of a tank, its attitude can be stabilized against vibration at the time of trigger and thus hitting accuracy can be enhanced.