KR101003337B1 - Micro actuator for depth of focus - Google Patents

Abstract

The present invention relates to a micro actuator for controlling depth of focus, comprising: a fixing part having a through hole formed therein; A movable part disposed in the through hole of the fixing part and having a light traveling path through hole formed therein; An elastic body installed at both ends of the fixing part and the movable part, respectively; A focusing lens installed in the light traveling path through hole of the movable part; Insulating resin or insulating ceramic surrounding the fixing part; A laminated coil embedded in the insulating resin or ceramic so as to surround the fixing part in a solenoid shape; A current control device for applying to the laminated coil; A magnetic body coupled to one end of the movable part; By providing a micro-actuator for controlling the depth of focus, comprising a micro-actuator for the depth of focus, the micro-actuator for the depth of focus can be reduced in size and compact by embedding the laminated coil portion inside the insulating resin, and changes the current direction applied to the laminated coil. It is possible to drive in both directions, and by manufacturing the lens moving device by micromachining technology, it is easy to mass production, improve the uniformity between each element, and increase the stroke length by adjusting the allowable displacement of the elastic body, The small mass of the moving parts reduces the response time.

Movable part, fixed part, elastic body, transparent substrate, laminated coil part

Description

MICRO ACTUATOR FOR CONTROLLING THE FOCAL LENGTH AND MANUFACTURING METHOD THEREOF

1 to 6 illustrate the structure and operation of a micro actuator for depth of focus according to an embodiment of the present invention.

1 is an exploded perspective view of a micro actuator for depth of focus adjustment

2 is a plan view of the lens driving apparatus of FIG.

3 is a plan view of the multilayer coil unit of FIG. 1;

4 is a cross-sectional view taken along the cutting line IV-IV of the micro actuator for depth of focus adjustment of FIG. 1.

5 is a conceptual diagram illustrating an operation of moving the movable part upward;

6 is a conceptual diagram illustrating an operation of moving the movable portion downward;

7A to 7C are cross-sectional views illustrating the lens driving apparatus of FIG. 1 according to a manufacturing step.

Description of the Related Art [0002]

110: lens moving device 111: moving part

113: elastic body 114: fixing part

115: magnetic material 116: transparent substrate                 

120: focusing lens 130: laminated coil portion

131: laminated coil 134: insulating resin or ceramic

140: optical disk 150: current control device

210: silicon substrate

The present invention relates to a micro-actuator for controlling depth of focus, and more particularly, to a micro-actuator for controlling depth of focus, capable of small size, light weight and low power, improving uniformity between elements, and enabling mass production at a low price.

In the case of an optical recording / reproducing apparatus using a rotating optical disk as a recording medium, the distance between the recording layer of the optical disk and the objective lens of the pickup optical system is due to the flatness error of the optical disk itself, the mechanical vibration and the eccentricity error caused by the driving unit for rotating the optical disk. Constantly changing, the signal-to-noise ratio for recording and reproducing becomes poor, thereby not only restricting the size of the unit bits that can be read and written, but also causing misreading and miswriting.

Accordingly, a focusing servo device that actively adjusts the focus of the input light to form the recording layer has been used, and the same principle is applied to measurement equipment such as a confocal microscope. .                         

Recent optical recording / reproducing apparatuses increase the recording density by reducing the size of data bits for storing optical information in order to increase the recording capacity, or form recording layers on both sides of the optical disk, or various recording surfaces of the optical disk. Methods of stacking recording films of layers and recording, reproducing and rewriting optical information on each recording film layer have been developed. In particular, in the case of a multi-layer recording film optical disc composed of a multi-layer recording film, not only the function of adjusting the fine depth of focus in the individual recording layer due to the disc flatness error, the vibration and eccentricity error, and the thickness error of the laminated films, It is essential to adjust the depth of focus so that the focus position can be moved between the individual recording film layers so that the laser beam can be focused between the respective recording films.

In view of these problems, conventionally, two cylindrical coils are arranged in a concentric manner so that the input light is focused on the recording layer of the optical disk, and the focusing position is adjusted by moving the focusing lens or the like in the optical axis direction with an electromagnetic driving force. It is used. However, such a conventional focus depth actuator is not only difficult to miniaturize, but also has a problem that it is difficult to adopt a small information storage device because of its large operating current.

In addition, as in the invention disclosed in Korean Patent Publication No. 2002-0014486, an actuator for adjusting the depth of focus driven by static electricity has been developed and utilized, but it is impossible to drive in both directions in the vertical direction and has a short stroke and high driving. There is a problem that a voltage is required.

 The present invention has been made to solve the above problems, small size, light weight and low power, can improve the uniformity between devices, mass production at a low price, the depth of focus that can be driven in both directions It is an object of the present invention to provide an adjustable micro actuator.

The present invention and the fixing portion formed through holes therein to achieve the object as described above; A movable part disposed in the through hole of the fixing part and having a light traveling path through hole formed therein; An elastic body installed at both ends of the fixing part and the movable part, respectively; A focusing lens installed in the light traveling path through hole of the movable part; Insulating resin or insulating ceramic surrounding the fixing part; A laminated coil embedded in the insulating resin or ceramic so as to surround the fixing part in a solenoid shape; A current control device for applying a current to the laminated coil; A magnetic body coupled to one end of the movable part; It provides a micro-actuator for the depth of focus characterized in that it comprises a.

By providing the micro-actuator for the depth of focus adjustment as described above, it is possible to drive in both directions, to improve the uniformity between devices by mass production, to increase the stroke distance, and to reduce the response time due to the small mass of the movable part.

Here, the insulating resin is preferably formed of a multi-layer PCB.

On the other hand, the insulating resin may be formed of a low temperature sintered laminated ceramic circuit board (LTCC; Low Temperature Co-fired Ceramic)

In addition, it is effective that the through-hole for assembly having a predetermined clearance with the outer surface of the fixing part is formed so that the insulating resin is assembled by fitting to facilitate alignment and assembly.

On the other hand, the insulating resin may be formed through holes for assembly having a predetermined gap with the outer surface of the fixing portion to be assembled by bonding by an adhesive to facilitate alignment and assembly.

The elastic body may be freely deformed with respect to the direction of the electromagnetic driving force, and is formed to have great rigidity with respect to the other directions.

In addition, the magnetic body is effectively configured to be integrated in the form of an annular or segmented annular portion in the outer peripheral portion of the optical path through hole.

In addition, it is preferable that the movable part has a lens mounting jaw formed in the light traveling path through hole formed in the movable part in order to easily align and assemble the focusing lens.

In addition, it is effective to further comprise a transparent substrate spaced apart from the lower end of the movable portion by a certain distance and coupled to the lower end of the fixed portion so as not to interfere with the movement of the movable portion by the electromagnetic drive.

In addition, an anti-reflective coating is preferably formed on the surface of the transparent substrate so as to minimize light loss due to light reflection.                     

The apparatus may further include an electrode pad formed on one surface of the transparent substrate protruding from one side of the insulating resin so as to protrude from the outer periphery of the insulating resin in order to apply current from the current controller, and connected to an end of the multilayer coil. It is effective to be configured.

In addition, the electrode pad may be connected to the end of the multilayer coil in order to apply current from the current control device, and may be formed on the top of the insulating resin.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

However, in describing the present invention, a detailed description of known functions or configurations will be omitted in order not to disturb the gist of the present invention.

1 to 6 show the configuration and operation of the micro-actuator for the depth of focus according to an embodiment of the present invention, Figure 1 is an exploded perspective view of the micro-actuator for focus depth adjustment, Figure 2 is a lens moving device of Figure 1 3 is a plan view of the multilayer coil unit of FIG. 1, FIG. 4 is a cross-sectional view taken along the cutting line IV-IV of the micro-actuator for controlling the depth of focus of FIG. 1, FIG. 5 is a conceptual diagram illustrating an operation of moving the movable part upward; 6 is a conceptual diagram illustrating an operation of moving the movable part downward.

As shown in the drawing, the micro-actuator for depth of focus adjustment includes a focusing lens 120 that forms a focus so that the laser beam is focused, and a lens moving device 110 that is coupled to the focusing lens 120 to precisely drive in the direction of the light path. ), The laminated coil unit 130 surrounding the lens movable device 110 to generate an induction magnetic field in the lens movable device 110, and the current control device 150 applying a current to the laminated coil part. It is composed.

The lens driving device 110 is manufactured by a semiconductor processing process and has an integrated form. The lens driving device 110 has a fixed portion 114 having a through hole 114a formed therein, and vertical movement in the light traveling path direction by an electromagnetic driving force. The movable part 111 provided in the inside of the fixed part through-hole 114a, the through-hole 112 which penetrates along the optical path in the center of the movable part 111, and the upper end of the optical path path through-hole 112 Opposite ends of the fixing portion 114 and the movable portion 111 to have a restoring force in a direction opposite to the displacement direction of the movable portion 111 and the lens mounting jaw 112a formed to easily assemble and align the focusing lens 120 in the And a magnetic body 115 integrally coupled to an upper end of the movable part 111 near the outer circumference of the optical path through hole through an elastic body 113 installed to be fixed to each other, and a ring shape or a segmented ring shape. , The number of the movable parts 111 by the electromagnetic drive Includes a transparent substrate 116 is bonded is provided to be spaced apart by a predetermined distance from the lower end of the movable portion 111 so that movement does not interfere with the high in the lower section (114).

At this time, the elastic body 113 is manufactured in a plate shape using a silicon substrate as a material by a semiconductor processing process, and rigidity is formed small so that free deformation is possible in the up-down direction, which is the direction of electromagnetic driving force, and in other directions. It is preferable that rigidity is formed large so that deformation may be suppressed.

In addition, the transparent substrate 116 serves to prevent contaminants from reaching the focusing lens 120 from the optical disk 140, and is processed to a predetermined thickness in consideration of the degree of refraction of light by the transparent substrate 116. On the surface, an antireflective coating should be formed to minimize light loss due to light reflection.

The multilayer coil unit 130 inserts the insulating resin 134 surrounding the fixing unit 114 and the lens moving device 110, and bonds the adhesive between the lens moving device 110 and the laminated coil part 130 by an adhesive. Coupling through hole 135 formed in the center of the insulating resin 134 so as to have a gap enough to be made, and a coil having a small diameter inside the insulating resin 134 to surround the fixing part 114 in a solenoid shape The multilayer coil 131 is formed of a metal conductor and two electrode pads 132 and 133 formed on the top of the insulating resin 134 to apply a driving current to the multilayer coil 131.

 In this case, the electrode pads 132 and 133 are formed on the upper end of the insulating resin 134 as described above, and the transparent substrate 116 is processed so that the transparent substrate 116 protrudes from one side of the insulating resin 134. It may be formed on one side of.

In addition, in order to minimize the size of the multilayer coil unit 130, the insulating resin 134 is formed of a multilayer printed circuit board or a low temperature cofired ceramic (LTCC) unit. More stacked coils 131 per area are formed to be embedded therein.

By such a configuration, as shown in FIGS. 5 and 6, the operation of the micro actuator for focus depth adjustment applies a current to the laminated coil 131 from the current controller 150, and surrounds the laminated coil 131. A magnetic field is formed in accordance with Ampere's law so that a magnetic field is integrated in the center of the lens driving device 110, and generates an electromagnetic driving force in the magnetic body 115 according to the direction of the magnetic field, and the magnetic body 115 by the electromagnetic driving force. When a displacement occurs in a predetermined direction of the movable part 111 which moves integrally with the), a resilient force is applied to the movable part 111 in proportion to the displacement in the opposite direction, and the restoring force and the electromagnetic driving force are parallel to each other. At this point, the displacement of the movable part 111 is determined, and since the electromagnetic driving force is proportional to the magnitude of the current applied from the current control device 150, the movable part 111 is adjusted by adjusting the magnitude of the applied current. It is implemented to adjust the displacement freely.

FIG. 5 is an operation conceptual view showing that the focusing lens 120 moves upward with respect to the optical disk 140 having the multilayer recording film structure. The magnetic force magnetized to the magnetic body 115 is illustrated as being downwardly magnetized. . The optical disk 140 having a multi-layer recording film structure includes an upper recording film 142 and a lower recording film 144 for data storage, a protective film 141 for protecting the recording film from the outside of the optical disk, and an upper portion to separate the recording film. And a separator 143 distributed between the recording film 142 and the lower recording film 144, and the substrate 145 of the optical disk.

Here, in the operation of moving the focus of the focusing lens 120 upward, the current is applied to the laminated coil 131 in the counterclockwise direction (when viewed from above) by the current control device 150, and according to the magnitude of the current Since the magnetic field B _u is upwardly distributed in the movable device 110 and the magnetic force of the magnetic body 115 is magnetized downward, the electromagnetic driving force F _u acts upward, so the movable part 111 moves upward. As a result, the focus of the focusing lens 120 is shortened by a depth l _u , and thus is formed on the upper recording film 142 of the optical disk 140.

In the same principle, FIG. 6 is an operation conceptual view showing that the focusing lens 120 moves downward with respect to the optical disc 140 having the multilayer recording film structure. The magnetic force magnetized on the magnetic body 115 is magnetized downward. Is illustrated. Here, in the operation of moving the focus of the focusing lens 120 downward, the current is applied to the laminated coil 131 in the clockwise direction (when viewed from above) by the current controller 150, and the lens moves according to the magnitude of the current. Since the magnetic field B _d is distributed downward in the apparatus 110, and the magnetic force of the magnetic body 115 is magnetized downward, the electromagnetic driving force F _d acts downward, so that the movable part 111 moves downward. Therefore, the focus of the focusing lens 120 is realized by making the depth l _d longer and confining the lower recording film 144 of the optical disk 140. At this time, the distance g _d between the lower end of the movable part 111 and the transparent substrate 116 should have a predetermined value or more so that mutual interference does not occur.

Therefore, the micro actuator for depth of focus adjustment of the present invention can increase the stroke length by adjusting the allowable displacement of the elastic body 113 to adjust the depth of focus, and according to the direction of the current applied to the laminated coil 131, I) It is possible to drive in the direction, and the response time can be reduced due to the small mass of the movable part, and the laminated coil part can be miniaturized by embedding more laminated coils per unit area in the insulating resin 134, and the smaller current Even when applied, the same electromagnetic driving force can be obtained, thereby reducing power consumption.                     

In the drawing, the operation of the fine focus correction in the same recording film is not separately shown, but the focus shifting operation and the driving principle between the recording films are the same, and there is only a difference that the displacement caused by the driving is minute.

7A to 7C are cross-sectional views illustrating the lens driving apparatus of FIG. 1 according to a manufacturing step. In the drawing, for convenience, one lens movable apparatus 110 is illustrated, but the actual process is performed in the form of a wafer-type substrate in which a plurality of elements shown in the figures are formed, and is manufactured in large quantities at the same time. ) Is implemented through the following steps by a semiconductor processing process.

As shown in FIG. 7A (a), etching mask thin films 211 and 212 are formed on the upper and lower surfaces of the silicon substrate 210 using the wafer-shaped silicon substrate 210 as a starting material. The etching mask thin film is formed of a material having high etching selectivity with silicon, such as a silicon oxide film, a silicon nitride film, or the like by a semiconductor device manufacturing process such as coating, vapor deposition, and plating.

Next, as shown in FIG. 7A (b), the metal thin film to be used as a seed of the electrolytic plating process by a thin film deposition method such as sublimation or sputtering on the upper surface of the silicon substrate 210. 213 is formed and the plating mold photoresist 214 is applied, and then a plating mold 214a is formed on the photoresist 214 through photolithography.

Subsequently, as shown in FIG. 7A (c), a magnetic material 115 such as nickel and ferrite is formed in the plating mold 214a by electroplating, and then used as the plating mold 214a. The photosensitive film 214 is removed.

Next, as shown in FIG. 7A (d), the metal thin film 213 of the portion other than the magnetic body 115 pattern is removed by etching.

Then, as shown in Figure 7a (e), the magnetic body 115 is applied to the photosensitive film on the patterned surface, by the photo-drawing process, the top of the fixing portion 114, the top of the elastic body 113 and In addition, the first etching mask pattern 215a is formed on a portion of which the upper end of the movable part 111 is formed except for the lens mounting jaw.

Next, as shown in FIG. 7B (f), the dry etching method such as reactive ion etching (RIE) or hydrofluoric acid may be performed on the etching mask thin film 211 on which the first etching mask pattern 215a is not formed. It is removed by etching using a chemical etching solution such as (Hydrofluoric Acid; HF).

Next, as shown in FIG. 7B (g), after the photosensitive film is coated on the lower surface of the silicon substrate 210, a double-sided alignment technique using an alignment mark already formed on the upper surface of the silicon substrate 210 ( The second etching mask pattern 216a is formed on a portion of the lower surface of the silicon substrate 210 to form the lower end of the fixing part 114 by double side alignment.

Next, as shown in FIG. 7B (h), the etching mask thin film 212 on which the second etching mask pattern 216a is not formed is subjected to dry etching such as reactive ion etching (RIE), hydrofluoric acid (HF), or the like. After removal by etching using the etchant solution, the silicon portion where the second etching mask pattern 216a is not formed is etched by silicon deep reactive ion etching (Silicon Deep RIE) technology to the depth that reaches the bottom of the movable part 111. Then, the photoresist remaining on the upper and lower surfaces of the silicon substrate 210 is removed.

Next, as shown in FIG. 7B (i), the third etching mask pattern 217A is formed on the bottom surface of the movable part 111 on the bottom surface of the silicon substrate 210 by a photo drawing process.

Next, as illustrated in FIG. 7B (j), reactive ion etching (RIE) is performed on the portion of the silicon on which the third etching mask patterns 212a and 217A formed on the bottom surface of the silicon substrate 210 are not formed. Or by etching using a silicon deep reactive ion etching technique to remove the third etching mask patterns 212a and 217A. In this process, the thickness of the silicon remaining after etching is the thickness of the elastic body 113.

Next, as shown in FIG. 7C (k), the third etching mask thin films 212a and 217A are removed and the transparent substrate 116 is bonded to the bottom surface of the exposed silicon substrate 210. When the material of the transparent substrate 116 is glass containing a predetermined sodium (Na), the bonding of the transparent substrate 116 is made by silicon-glass anodic bonding, which is one of microfabrication techniques.

Next, as shown in FIG. 7C (l), a portion of the silicon on which the first etching mask pattern 215a is not formed on the upper surface of the silicon substrate 210 may be formed using reactive ion etching (RIE) or silicon deep reactive ion etching. The silicon substrate 210 may be penetrated by etching through the same. In this process, the light traveling path through hole 112 and the lens mounting jaw 112a are completed.

Next, as shown in FIG. 7C (m), the movable part 111, the elastic body 113, and the fixing part 114 are completed by removing the etch mask thin film 211 exposed on the upper surface of the silicon substrate 210. In addition, the lens movable apparatus 110 of the present invention is completed by separating the transparent substrate 116 into individual chips having a predetermined size by a dicing method or the like in a wafer form substrate.

When the insulation resin 134 is formed of a ceramic circuit board, the multilayer coil unit 130 is formed by filling a ceramic circuit board with a plated metal coil and stacking each substrate, and the insulation resin 134 is a printed circuit. In the case where the substrate is formed as a substrate, the plated metal coils are formed together by molding and then laminated.

Meanwhile, the multilayer coil unit 130 in which the focusing lens 120 is mounted and assembled in the optical path path through hole 112 of the completed lens moving device 110, and the insulation resin is formed of a multilayer printed circuit board or a multilayer ceramic substrate. ) Into the assembling through-hole 135, and attaching the inner surface of the assembling through-hole 135 and the outer surface of the fixing part 114 of the lens moving device 110 with an adhesive, or fitting by a certain tolerance. By combining the fitting and connecting the current control device to the electrode pads (132, 133), the micro-actuator for controlling the depth of focus of the present invention is completed.

Since the lens moving device 111 is manufactured by a semiconductor manufacturing process and a micromachining technology, which is a precision processing technology, mass production is easy, and uniformity between elements can be improved, and the multilayer coil part 130 is formed inside the insulating resin 134. Since the multilayer coil 131 formed of a coil metal conductor having a smaller diameter per unit area can be embedded, it contributes to miniaturization, and the same electromagnetic driving force can be obtained at a lower current, thereby reducing power consumption.

Although the preferred embodiments of the present invention have been described above by way of example, the scope of the present invention is not limited to these specific embodiments, and may be appropriately changed within the scope described in the claims.

As described above, according to the present invention, the depth of focus micro-actuator can be miniaturized and light-weighted by embedding the laminated coil part inside the insulating resin, and bidirectional driving is possible by changing the current direction applied to the laminated coil. By manufacturing the movable device by micromachining technology, mass production is easy and the uniformity between elements can be improved. In addition, by adjusting the allowable displacement of the elastic body 113, the stroke length can be increased, and the response time can be reduced due to the small mass of the movable part.

Claims (24)

A fixing part having a through hole formed therein; A movable part disposed in the through hole of the fixing part and having a light traveling path through hole formed therein; An elastic body fixed at both ends of the fixing part and the movable part; A focusing lens installed in the light traveling path through hole of the movable part; An insulating resin surrounding the fixing portion; A coil-shaped metal conductor having a first diameter embedded in said insulating resin so as to surround said fixing portion; A laminated coil embedded in the insulating resin to surround the fixing part in a solenoid shape; A current control device configured to apply a current to the laminated coil; A magnetic body coupled to one end of the movable part; Micro actuator for depth of focus, characterized in that it comprises a. The method of claim 1, The insulating resin is a micro actuator for depth of focus, characterized in that the multilayer printed circuit board. The method of claim 1, The insulation actuator is a micro actuator for depth of focus, characterized in that the laminated ceramic circuit board. The method of claim 1, The insulated resin micro-actuator for controlling the depth of focus, characterized in that the through-hole for assembly located at a predetermined distance from the outer surface of the fixing portion is formed so that the fixing portion is inserted. The method of claim 1, And a through hole for assembly located at a predetermined distance from an outer surface of the fixing part so that the fixing part is attached to the insulating resin by using an adhesive. The method of claim 1, The elastic body is deformable in the direction of the electromagnetic drive force, and the rigidity for the depth of focus micro-actuator characterized in that (rigid) for the other directions. The method of claim 1, The magnetic body is ring-shaped, the depth of focus micro-actuator, characterized in that located on the outer peripheral portion of the optical path through hole. The method of claim 1, And the movable unit includes a lens mounting unit formed in a light traveling path through hole formed in the movable unit to align and assemble the focusing lens. The method according to any one of claims 1 to 8, A micro actuator for depth of focus, characterized in that it further comprises a transparent substrate coupled to the bottom of the fixed portion spaced apart from the bottom of the movable portion. The method of claim 9, The surface of the transparent substrate is a micro-actuator for controlling the depth of focus, characterized in that the anti-reflective coating is formed to minimize the light loss due to light reflection. The method of claim 9, The first side surface of the transparent substrate further includes an electrode pad protruding from an outer circumference of the insulating resin and formed on a protruding surface of the transparent substrate so as to be connected to one end of the multilayer coil in order to apply current from the current control device. A micro actuator for depth of focus, characterized in that. The method of claim 1, And an electrode pad formed on the first end of the insulating resin so as to be connected to one end of the multilayer coil to apply current from the current control device. A lens for forming a focus by focusing light incident from the light source; A lens mounting unit mounted inside the lens and moving the lens in an axial direction; And An electromagnetic force generating device including a stationary magnetic field generating member having a magnetic field in a predetermined direction and a variable magnetic field generating member whose direction and intensity of the magnetic field change in accordance with the direction and amount of current. The lens mounting unit may include a fixing part having a through hole therein; A movable part positioned in a through hole of the fixing part and having an optical path formed therein so that the lens is mounted therein; And a plurality of elastic supports for elastically suspending the movable portion to the fixed portion. And the electromagnetic force generating device is installed around the lens mounting unit and moves the lens in the direction of the electromagnetic force generated by the interaction of the two magnetic field generating members. The method of claim 13, The stator magnetic field generating member is a magnetic body positioned near the lens and installed on one side of the movable part. The method of claim 14, The magnetic actuator is a depth of focus micro-actuator characterized in that it has an annular or annular divided into several parts. The method of claim 13, And the variable magnetic field generating member is a stacked coil installed to surround the fixing part. The method of claim 16, The laminated coil, An insulating resin having a through hole for assembly with the fixing part; And And a coil-shaped metal conductor having a small diameter embedded in the insulating resin so as to surround the fixing part. The method of claim 17, The multilayer coil is a micro-actuator for depth of focus, characterized in that formed of a multilayer printed circuit board. The method of claim 17, The lens mounting unit is a micro-actuator for the depth of focus characterized in that it comprises a transparent substrate which is located at a predetermined distance from the plurality of elastic support and the movable portion, coupled to one side of the fixing portion. The method of claim 19, An anti-reflective coating film is formed on the surface of the transparent substrate. The method of claim 19, One side of the transparent substrate is protruded relative to the outer peripheral surface of the insulating resin, an electrode pad is formed on the protruding surface of the transparent substrate to be connected to the metal conductor and electrically connected to the current regulator, the metal conductor is a coil A micro actuator for depth of focus, characterized in that the metal conductor of the shape. The method of claim 19, An electrode pad is connected to one end of the metal conductor so as to be formed on top of the insulating resin and electrically connected to the current control device, and the metal conductor is a coil-shaped metal conductor. The method of claim 17, The multilayer coil is a micro actuator for depth of focus, characterized in that the laminated ceramic circuit board. 24. The method of claim 23, The multilayer ceramic circuit board is a low-temperature co-fired ceramic (LTCC) substrate, characterized in that the depth of focus micro-actuator.

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