KR20090014584A - Variable focus optical device using liquid optical material and fabrication methods thereof - Google Patents

Abstract

A variable focus optical device and a manufacturing method thereof are provided to manufacture a miniaturized optical device and improve optical characteristic and productivity by using liquid optical material enabling adjustment of volume without liquid injection/exhaust hole. A lens unit(100) includes a chamber containing liquid optical material(130). A plurality of holes(350a~350d) are formed at a cover frame(300) in order to change volume of the liquid optical material. The holes are arranged between the cover frame and the lens unit. An actuator(200) is located at a lower part of the holes and is used to adjust volume of the liquid optical material.

Description

Variable focus optical device using liquid optical body and manufacturing methods thereof

The present invention relates to a variable focusing optical device and a method for manufacturing the same, and more particularly, to a variable focusing optical device and a method for manufacturing the same, which can vary the focal length by using a liquid optical body.

Modern wireless mobile communication devices have evolved beyond simple phone functions and message transfer functions into versatile electronic devices capable of performing various functions such as cameras, games, music playback, and the Internet. In addition, in order to maximize the convenience and aesthetics of the user, it is increasingly smaller and slim.

Accordingly, attempts have been made to integrate many modules in increasingly smaller spaces. Among these, one of the most difficult modules to be miniaturized is a camera module. That is, the camera module generally uses a lens, and reducing the volume and thickness of the module in which the lens is embedded is considered the most difficult. In particular, in order to obtain a better image, an auto focus function, an anti-shake function, a zoom function, and the like must also be integrated, but at present, there is a problem in that it is difficult to add such a function due to size limitations.

In particular, the user can utilize the camera function in various ways. For example, you can take a picture of a distant subject, or try to take a close-up shot with a business card or card at a distance of 5 to 10 cm. However, unless a professional camera such as a digital camera is used, it is difficult to perform such close-up photography because the focal length is generally fixed. Therefore, there is a problem that the image is blurred when attempting close-up photography.

In order to solve these problems, there have been attempts to change the focal length by using a liquid optical body. This is a method in which the lens is composed of an optical body in a liquid state and the lens curvature is changed by adjusting an inflow or outflow amount of the optical body. In this case, various functions such as an auto focus or a zoom function can be implemented without a moving part, thereby minimizing the volume or thickness of the lens unit.

However, in order to manufacture an optical device using a liquid optical body, a process of injecting a liquid optical body is required. This injection process has a problem in that process difficulty is large. In particular, since a bubble is inevitably generated in the sealing process after the liquid injection and is present in the liquid optical body, there is also a problem that the optical properties are deteriorated. In addition, due to the small injection / discharge port, the physical properties such as density and viscosity of the liquid optical body is limited, there is also a difficulty in creating a liquid optical body having a high refractive index.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to provide a variable focusing optical device capable of miniaturization and slimming by changing the focus by adjusting the volume of a liquid optical body without a liquid inlet / outlet. have.

Another object of the present invention is to provide a variable focusing optical device using a liquid optical body that can be adjusted in volume without a liquid injection / discharge port in a very small size, to provide a manufacturing method that can improve the optical properties and productivity.

According to one or more embodiments of the present invention, a variable focus optical device includes a lens unit including a chamber containing a liquid optical material, and a volume change for the liquid optical body. A cover frame having a plurality of holes and an actuator disposed between the cover frame and the lens unit, the actuator capable of adjusting the volume of the liquid optical body located below the plurality of holes.

In this case, the lens unit may include a transparent wafer, a wall forming a chamber containing the liquid optical body on the transparent wafer, and a membrane covering the liquid optical body filling the chamber.

Here, the actuator may be coupled to the membrane in the lens unit.

The lens unit may further include a support part supporting the membrane in the chamber and allowing the liquid optical body to flow in a space between the bottom surface and a distance from the bottom surface of the chamber. have.

According to another embodiment, the lens unit is in contact with the chamber bottom surface in the chamber, spaced apart from the lower surface of the membrane by a certain distance to allow the liquid optical body to flow in the space between the membrane and the lower surface It may further include a support.

In the above embodiments, the wafer, the wall and the support may be integrally formed.

In addition, the support part may be formed at a position corresponding to a partition portion formed to form the hole in the cover frame.

On the other hand, according to another embodiment, the lens unit further comprises a groove (groove) formed in the edge region on the upper surface of the wall, wherein the membrane is coupled to the wall through the groove, the liquid optical Can cover the sieve.

In addition, the UV bonding layer formed on the surface of the wall and the transparent wafer may be further included.

On the other hand, the method of manufacturing a variable focusing optical device according to an embodiment of the present invention, (a) forming a wall forming a chamber on one surface of the membrane, (b) dispensing a liquid optical body into the chamber, (c) vacuum bonding a transparent wafer on top of the chamber containing the liquid optics, and (d) an actuator for modifying the membrane on the other surface of the membrane and a plurality of variations for volume change of the liquid optics Forming a cover frame in which two holes are formed.

Here, the step (c), (c1) deforming the membrane forming the bottom surface of the chamber containing the liquid optical body, bonding the transparent wafer in a vacuum state, (c2) by releasing the vacuum state Restoring the modified membrane.

In this case, step (c1) may deform the membrane in a direction opposite to the transparent wafer using at least one of gravity and electrostatic force.

Alternatively, the manufacturing method may further include forming a UV bonding layer on the wall surface when the wall is formed on one surface of the membrane. In this case, the step (b) is to dispense the liquid optical body to the lower surface of the UV bonding layer, and the step (c), using the UV bonding layer in the state in which the liquid optical body is dispensed The transparent wafer may be vacuum bonded to the wall, and UV coating may be performed to shrink the UV bonding layer.

Alternatively, as described above, the method may further include forming a UV bonding layer on the wall surface even in an embodiment in which the membrane is deformed in the opposite direction to the transparent wafer using at least one of gravity and electrostatic force, and then restored. have. Even in this case, the step (c) may vacuum-bond the transparent wafer to the wall using the UV bonding layer and perform UV coating to shrink the UV bonding layer.

On the other hand, the step (a), (a1) etching the wafer to form a wall forming a chamber of a predetermined shape and (a2) by coupling the wafer to one surface of the membrane, to form a chamber on the membrane It may include a step.

In this case, in the step (a1), a support part allowing the liquid optical body to flow in a space between the bottom surface and a distance from the bottom surface of the chamber may be manufactured together with the wall.

Alternatively, in the step (a1), the support may be manufactured together with the wall to allow the liquid optical body to flow in a space between the one surface of the membrane and a distance from the one surface of the membrane.

On the other hand, the step (d), the step of forming the actuator in a predetermined area of the other surface of the membrane and the cover frame to the other surface of the membrane so that the actuator is located inside at least one of the plurality of holes Bonding in the direction.

Also, preferably, when the plurality of chambers are formed on the membrane, the manufacturing method may further include a step of dicing and separating the chambers into a plurality of variable focusing optical devices.

On the other hand, the variable focus optical device manufacturing method according to another embodiment of the present invention, forming a wall constituting at least one chamber on a transparent wafer, dispensing a liquid optical body in the chamber, than the liquid optical body Dispensing a liquid membrane having a low specific gravity on the liquid optical body and when the liquid membrane is cured to form a membrane, an actuator for deforming the membrane on the membrane and a plurality of volumes for volume change of the liquid optical body. Forming a cover frame in which two holes are formed.

In this case, the forming of the wall constituting the chamber on the transparent wafer, etching the wafer to produce the wall and bonding the wall to one surface of the transparent wafer, the bottom surface of the transparent wafer It may comprise the step of forming a chamber.

Meanwhile, in the manufacturing of the wall by etching the wafer, the wafer may be etched to support the liquid optical body to flow in a space between the bottom surface and a distance from the bottom surface of the chamber. It can be produced together with the month.

Alternatively, in the manufacturing of the wall by etching the wafer, the wafer may be etched so that the liquid optical body may flow in a space between the one surface of the membrane and a distance from the one surface of the membrane. May be produced together with the month.

Meanwhile, in the forming of the wall constituting the chamber on the transparent wafer, a groove may be manufactured at the edge of the upper surface of the wall. In this case, in the dispensing of the liquid membrane, the liquid membrane may be dispensed up to the groove portion to cover the liquid optical body.

The manufacturing method may further include, when the plurality of chambers are formed on the transparent wafer, dicing and separating the chambers for each chamber to collectively manufacture the plurality of variable focusing optical devices.

The variable focusing optical apparatus according to the present invention can be miniaturized and slimmed by using a liquid optical body, and can have excellent optical properties without generating voids. Particularly, since it is manufactured in a structure that does not require a liquid injection or discharge port, a liquid optical body having excellent hermetic properties, high density and viscosity may be used, and liquid optical during liquid injection and discharge. The sieve can be prevented from moving locally unstable. In addition, according to the present invention, it is possible to easily manufacture such a variable focusing optical device in a simple manner, which can reduce the process failure rate, manufacturing cost, processing time, etc., and enables high product reliability and mass production.

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

1 is a schematic diagram showing the configuration of a variable focus optical device according to an embodiment of the present invention. According to FIG. 1, the present variable focusing optical apparatus includes a lens unit 100, an actuator 200, and a cover frame 300.

The lens unit 100 refers to a portion including a liquid optical material to perform a lens role. In detail, the lens unit 100 includes a transparent wafer 110, a wall 120, a support 125, a liquid optical body 130, and a membrane 140.

The transparent wafer 110 is a wafer made of a material such as glass to allow light to pass therethrough. The transparent wafer 110 may be manufactured using Pyrex glass. The wall 120 forms a chamber of a predetermined size and shape on one surface of the transparent wafer 110, and the liquid optical body 130 is contained in the chamber.

The liquid optical body 130 is introduced into the chamber by a dispensing method, and thus does not require a separate liquid inlet. In this case, as the liquid optical body 130, a product having low vacuum volatility (boiling point at 5 mmHg vacuum degree of about 210 to 250 degrees Celsius) and having a large refractive index or specific gravity (refractive index of 1.555 or more and specific gravity of 1.9 or more) may be used. . For example, HIVAC F-4, HIVAC F-5 manufactured by ShinEtsu Silicon, or LS-5241-10, manufactured by Nusil Technology, may be used as the liquid optical body 130.

On the other hand, the support part 125 is located inside the chamber and supports the membrane in contact with it. The space below the support 125, ie, the space between the support 125 and the bottom of the chamber, serves as a moving passage in the chamber of the liquid optical body 130. The position of the support 125 may vary depending on the embodiment, which will be described later.

The membrane 140 is formed on the liquid optical body 130 contained in the chamber. The membrane 140 is easily deformed and made of a transparent material. As the membrane 140 is deformed, the thickness of the lower liquid optical body 130 is adjusted, and as a result, the focus may be changed. As the membrane 140, polydimethylsiloxane (PDMS) or Poly Ethylene glycol (PEG) such as Sylgard 184 may be used.

An actuator 200 is formed on the membrane 140. The actuator 200 is configured to cause deformation of the membrane 140. Specifically, the actuator 200 may be manufactured in a form in which the first electrode, the piezoelectric layer, and the second electrode are sequentially stacked. Accordingly, the piezoelectric phenomenon may occur when the driving power is applied to deform the membrane 140.

The actuator 200 may be formed in the remaining portion of the membrane 140 except for the predetermined region 360. The region 360 from which the actuator 200 is excluded may be a portion that substantially acts as a lens. The actuator 200 may deform the lower membrane 140 to change the volume of the liquid optical body 130 under the membrane 140.

The cover frame 300 is formed on the actuator 200. The cover frame 300 fixes the chamber, which is an isolated space in which the liquid optical body 130 is filled, and serves to stabilize the flow of the liquid optical body 130. That is, the solidified cover frame 300 supports the actuator 200 and the lens unit 100, so that the thickness of the liquid optical body 130 can be stably adjusted. To this end, the cover frame 300 includes a plurality of holes (350a, 350c, 360). The cover frame 300 may be made of silicon or glass wafer.

Each hole provides a space in which the thickness of the liquid optical body 130 can be adjusted. That is, in FIG. 1, an actuator 200 may be disposed in both holes 350a and 350c to bend the membrane 140 below or upward. Accordingly, the liquid optical body 130 may move in the chamber to increase or decrease the thickness of the liquid optical body 130 in the center hole 360. Accordingly, the focus of the lens can be changed.

The variable focus optical apparatus of FIG. 1 operates in a manner in which the liquid optical body 130 is introduced into the chamber by a dispensing method, and the liquid optical body 130 is adjusted in volume by deformation of the membrane 140. There is no need to have a configuration such as an inlet and a liquid outlet.

2 and 3 are schematic diagrams for describing a focus adjustment process of the variable focus optical device of FIG. 1. First, as shown in FIG. 2, when the membrane 140 is bent downward in both holes 350a and 350c, the membrane 140 in the center hole 360 is upward by the lower liquid optical body 130. Will be bent. Accordingly, it can be seen that the thickness of the liquid optical body 130 in the center hole 360 is increased.

3 is a schematic diagram three-dimensionally illustrating the focus adjustment process of FIG. For convenience of description, the illustration of the cover frame 300 is omitted. According to FIG. 3, the downward force is applied to the peripheral holes 350a, 350b, and 350c except for the center hole 360, such that the liquid optical body 130 is moved below the center hole 360. Accordingly, it can be seen that the thickness d2 of the liquid optical body 130 below the center hole 360 is greater than the thickness d1 of the liquid optical body 130 below the peripheral holes 350a, 350b, and 350c.

4 and 5 are schematic diagrams illustrating a configuration of a variable focus optical device according to various embodiments of the present disclosure. According to the embodiment of Figure 4, the support 125 is manufactured in the form in contact with the chamber bottom surface. Accordingly, the moving passage of the liquid optical body 130 is formed between the support 125 and the membrane 140 so that the liquid optical body 130 can move in both directions within the moving passage.

Alternatively, as shown in FIG. 5, the support 125 and the wall 120 may be integrally formed with the transparent wafer 110. That is, by etching the surface of the transparent wafer 110 in the form of a chamber, the support 125 and the wall 120 can be manufactured at once.

Meanwhile, in FIGS. 1 to 5, the support part 125 may be formed under the partition wall 310 in the cover frame 300. In order to form a plurality of holes in the cover frame 300, the partition wall 310 is formed inside the outer frame, and the support part 125 may be formed at a position corresponding to the lower part of the partition wall 310 in the chamber. In this way, by adjusting the position and size of the support 125, the moving speed of the liquid optical body 130 can be adjusted.

6A to 6H are schematic views for explaining an embodiment of a manufacturing method for manufacturing the variable focusing optical device.

First, the wall 120 and the support 125 are manufactured as shown in FIG. 6A. That is, the wafer is etched and patterned in the form of the wall 120 and the support 125. Specifically, the wall 120 and the support part 125 can be manufactured by the double side DRIE method using a silicon wafer.

Next, the wall 120 and the support 125 are bonded onto the membrane 140 as shown in FIG. 6B. In this case, it is preferable to perform pretreatment for hermetic bonding on the surface of the wall 120 and the support 125 prior to bonding with the membrane 140. Accordingly, when bonding is performed, a chamber is formed in which the membrane 140 is the bottom surface and the wall 120 is the side surface.

Next, as shown in FIG. 6C, the liquid optical body 130 is dispensed into the chamber.

In this case, as shown in FIG. 6D, gravity or the like acts to cause the membrane 140 in the chamber containing the liquid optical body 130 to sag downward, thereby forming a convex shape. As a result, the liquid optic body 130 may be contained in a larger amount than the original chamber size. In this case, when the force of gravity acting on the membrane 140 is not large, the degree of sagging of the membrane 140 may be adjusted by additionally applying an electrostatic force in the downward direction of the membrane 140. Specifically, the membrane 140 may be convexly elastically deformed downward by using an electrostatic chuck including a jig. At this time, it is preferable to adjust the dispensing amount of the liquid optical body 130 to a level slightly lower than the upper surface of the wall 120 so that the liquid optical body 130 contained in the chamber does not exceed the upper surface of the wall 120. .

Then, the transparent wafer 110 is bonded in a vacuum state as in FIG. 6E to close the chamber. Specifically, under an environment such as a vacuum chamber, one surface of the transparent wafer 110 and the upper surface of the wall 120 are press-bonded. UV curable adhesives may be used for bonding. In addition, a thermal curable adhesive or a material capable of photolithography, such as a dry film resistor, may be used.

After the transparent wafer 110 is bonded, the vacuum is released as shown in FIG. 6F. Accordingly, while the membrane 140 is returned to the horizontal state by the atmospheric pressure, vacuum spaces existing in the transparent wafer 110, the wall 120, and the membrane 140 are removed, and the liquid optical body 130 is removed. Only the chamber will be filled. In this case, it is desirable to remove the electrostatic force so that the membrane 140 can return well to the horizontal state. As such, as the compression bonding is performed in a vacuum state, void formation such as bubbles can be prevented.

Next, UV (Ultra Violet) is irradiated onto the transparent wafer 110 as shown in FIG. 6G to cure the adhesive present between the transparent wafer 110 and the upper surface of the wall 120. Accordingly, the transparent wafer 110 may be firmly bonded to the upper portion of the wall 120.

Next, as shown in FIG. 6h, the actuator 200 and the cover frame 300 are attached to the surface of the membrane 140. The cover frame 300 may be manufactured separately by etching a separate wafer and forming a plurality of holes. When the cover frame 300 is attached, it is preferable to arrange the holes so that the holes are located at the portion of the surface of the membrane 140 where actual deformation should occur. Accordingly, since the remaining portion except for the portion where the actual deformation occurs is fixed by the cover frame 300, a robust variable focusing optical device may be formed.

7A to 7D are schematic views for explaining the present production method in three dimensions. First, according to FIG. 7A, a frame including a wall 120 and a support part 125 is manufactured, and then bonded to the membrane 140. The vertical cross-sectional view cut in the I direction shown in FIG. 7A corresponds to FIG. 6A.

Next, as shown in FIG. 7B, the liquid optical body 130 is dispensed into the chamber. Accordingly, the liquid optical body 130 fills the chamber region and the upper portion of the support 125 at positions corresponding to the holes 350a to 350d and 360 of the cover frame 300.

Then, the transparent wafer 110 is bonded in a vacuum state as shown in FIG. 7C, and the vacuum is released as shown in FIG. 7D to fill the chamber only with the liquid optical body 130.

8A to 8D are schematic views for explaining still another embodiment of the method of manufacturing the variable focus optical device. First, as shown in FIG. 8A, a frame formed of the wall 120 and the support 125 is bonded to the transparent wafer 110 to form a chamber. Bonding of the frame and the transparent wafer 110 may be performed according to an airtight bonding method or an anodical bonding method. In this case, the groove 121 is formed in the inner edge region of the upper surface of the wall 120.

Next, as shown in FIG. 8B, the liquid optical body 130 is dispensed to fill the inside of the chamber. In this case, the liquid optical body 130 is preferably filled to the bottom level of the groove 121. In addition, prior to dispensing the liquid optical body 130, pre-treatment may be performed on the support 125 and the wall surface to improve wetting. As the liquid optical body 130, LS-5241-10 manufactured by Nusil Technology, which has a specific gravity of about 1.9, may be used.

Next, as shown in FIG. 8C, the liquid membrane 140 ′ is dispensed to cover the upper portion of the liquid optical body 130. The liquid membrane 140 ′ fills up to the groove 121 and is dispensed to a level close to the top surface of the wall 120. In this case, the liquid membrane 140 ′ having a specific gravity lower than that of the liquid optical body 130 is selected so as not to be mixed with the liquid optical body 130. Accordingly, the liquid membrane 140 ′ is suspended above the liquid optical body 130. In such a state, heat treatment or the like is performed to solidify the liquid membrane 140 ', thereby forming the membrane 140. As such, by dispensing the liquid membrane 140 ′ on the primarily dispensed liquid optical body 130, voids may occur between the liquid optical body 130 and the membrane 140. There is no room left.

Next, as shown in FIG. 8D, the actuator 200 and the cover frame 300 are formed on the membrane 140. Accordingly, except that a part of the membrane 140 is formed on a part of the upper surface of the wall 120, the same variable focus optical device as that of FIG. 1 can be manufactured.

In each of the manufacturing methods described with reference to FIGS. 6A to 6H and FIGS. 8A to 8D, the wall 120, the support 125, the transparent wafer 110, and the like may be integrally manufactured. The location can also be changed. Accordingly, the variable focus optical device of the structure shown in FIGS. 4 and 5 can be manufactured in the same manner.

On the other hand, when dispensing in excess of a predetermined level during the dispensing process of the liquid optical body 130 or the liquid membrane 140 ', by applying a tool such as a needle (needle) to the liquid surface by using a capillary phenomenon Can be lowered.

9A and 9B are schematic diagrams showing various initial states of the variable focus optical device manufactured according to the manufacturing method illustrated in FIGS. 6A to 6H. That is, the amount of the liquid optical body 130 entering the chamber may be adjusted by appropriately adjusting the electrostatic force applied to the membrane 140 during the manufacturing process illustrated in FIGS. 6A to 6H. Specifically, as shown in FIG. 6A, a large amount of the liquid optical body 130 may be dispensed so as to be able to operate as a convex lens in an initial state. Alternatively, as shown in FIG. 6B, the liquid optical body 130 may be dispensed with a small portion to operate as a concave lens in an initial state.

On the other hand, the fabrication methods may be used to fabricate a plurality of variable focusing optics in a batch. 10 is a schematic view for explaining a process of manufacturing a plurality of variable focus optical devices.

That is, each of the manufacturing methods shown in FIGS. 6A to 6H and 8A to 8D may produce a plurality of chambers in the manufacturing process. Accordingly, the liquid optical body 130 may be dispensed for each chamber, the membrane 140 and the actuator 200 may be formed, and then fixed with one cover frame 300. Accordingly, when the varifocal optical device is configured for each chamber, as shown in FIG. 10, dicing is performed to separate the varifocal optical devices so that a plurality of varifocal optical devices can be manufactured at once. do.

In addition, the present variable focusing optical device is formed of a transparent wafer 110 on one side and a cover frame 300 on the other side, and integrating one of the two sides into an external wafer such as a PCB according to a design purpose. Can be used with other chips.

That is, as shown in FIG. 11A, the variable focus optical device 700 may be wafer-to-wafer bonded to the external wafer 800 in the direction of the transparent wafer 110. Accordingly, it may be integrated with a CMOS or other lens provided in the external wafer 800.

Alternatively, as shown in FIG. 11B, the cover frame 300 side of the variable focus optical device 700 may be integrated in the direction of the wafer 800 to implement an integrated circuit.

12A to 12C and 13 are schematic views for explaining various modified examples of the manufacturing method illustrated in FIGS. 6A to 6H.

First, in the case of FIGS. 12A to 12C, a method of removing the empty space in the chamber using the UV bonding layer 150 will be described. That is, when the chamber is formed on the membrane 140 as shown in Figure 6b, the UV bonding layer 150 is formed on the surface of the wall 120 constituting the chamber. In this case, after forming a groove by etching a portion of the surface of the wall 120, the UV bonding layer 150 may be formed based on the groove. The UV bonding layer 150 means an adhesive having a curable property by UV.

As such, when the UV bonding layer 150 is formed, the liquid optical body 130 is dispensed as shown in FIG. 12B. In this case, the liquid optical body 130 is preferably dispensed only to the lower portion of the upper surface of the UV bonding layer 150. Specifically, it is preferable to dispense while calculating only the amount of space of the UV bonding layer 150 to be contracted by calculating the degree of shrinkage of the UV bonding layer 150.

Then, in the vacuum state, the transparent wafer 110 is bonded to the upper side of the wall 120 using the UV bonding layer 150, and then irradiated with UV to cure the UV bonding layer 150. In this process, since the UV bonding layer 150 shrinks as shown in FIG. 12C, the space between the membrane 140 and the transparent wafer 110 is completely filled only with the liquid optical body 130.

Meanwhile, as illustrated in FIG. 6D, the membrane 140 may be deformed and restored by using gravity or electrostatic force, and the shrinkage phenomenon of the UV bonding layer 150 may also be used to remove the empty space in the chamber.

That is, as shown in FIG. 13, when the liquid optical body 130 is dispensed after the UV bonding layer 150 is formed, gravity and electrostatic force are applied to the lower side of the membrane 140 to induce deformation of the membrane 140. . Then, when bonding of the transparent wafer 110 is made, the vacuum is released to restore the membrane 140, and the UV bonding layer 150 is shrunk by irradiating UV to completely fill the chamber with only the liquid optical body 130. It becomes possible.

While the above has been shown and described with respect to preferred embodiments of the invention, the invention is not limited to the specific embodiments described above, it is usually in the technical field to which the invention belongs without departing from the spirit of the invention claimed in the claims. Various modifications can be made by those skilled in the art, and these modifications should not be individually understood from the technical spirit or the prospect of the present invention.

The varifocal optical device according to the present invention can be applied to an ultra-small multifunctional electronic device such as a mobile phone, a PDA, etc. having a camera function.

1 is a schematic diagram showing the configuration of a variable focus optical device according to an embodiment of the present invention;

2 is a schematic diagram illustrating a state in which a focus is changed in the variable focus optical device of FIG. 1;

3 is a schematic diagram three-dimensionally showing a state in which the focus is changed in the variable focus optical device of FIG.

4 and 5 are schematic diagrams illustrating a configuration of a variable focus optical device according to various embodiments of the present disclosure;

6A to 6H are schematic views showing one embodiment of a manufacturing method for manufacturing the variable focusing optical device;

7A to 7D are schematic views for explaining three-dimensionally the manufacturing method shown in FIGS. 6A to 6H;

8A to 8D are schematic views showing another embodiment of a manufacturing method for manufacturing the variable focus optical device;

9A and 9B are schematic diagrams showing various initial states of the present varifocal optical device;

10 is a schematic diagram for explaining a process of collectively manufacturing a plurality of variable focus optical devices;

11A and 11B are schematic views for explaining various applications of the variable focus optical device, and

12A to 12C and FIG. 13 are schematic diagrams showing various modifications of the manufacturing method shown in FIGS. 6A to 6H.

Explanation of symbols on the main parts of the drawing

110: transparent wafer 120: month

130: liquid optical body 125: support

140: membrane 200: actuator

300: Cover frame 350a ~ 350d, 360: Hole

Claims (25)

A lens unit including a chamber containing a liquid optical material; A cover frame having a plurality of holes for changing the volume of the liquid optical body; And, And an actuator disposed between the cover frame and the lens unit and capable of adjusting a volume of the liquid optical body positioned below the plurality of holes. The method of claim 1, The lens unit, Transparent wafers; A wall forming a chamber containing the liquid optical body on the transparent wafer; And, And a membrane covering the liquid optical body filling the chamber. The method of claim 2, The actuator is, And a variable focusing optical device coupled to the membrane in the lens portion. The method of claim 2, The lens unit, And a support for supporting the membrane in the chamber and allowing the liquid optical body to flow in a space between the bottom surface and a spaced distance from the bottom surface of the chamber. Device. The method of claim 2, The lens unit, And a support part in contact with the chamber bottom surface in the chamber and spaced apart from the lower surface of the membrane by a predetermined distance to allow the liquid optical body to flow in a space between the membrane and the lower surface of the membrane. Focusing optics. The method according to claim 4 or 5, And the wafer, the wall and the support are integrally formed. The method according to claim 4 or 5, The support portion, And a focal point formed at a position corresponding to a partition portion formed to form the hole in the cover frame. The method of claim 2, The lens unit, A groove formed in an edge region on the surface of the wall; And the membrane is coupled to the wall through the groove and covers the liquid optical body. The method of claim 2, And a UV bonding layer formed on the surface of the wall and the transparent wafer. In the manufacturing method of a varifocal optical device, (a) forming a wall forming a chamber on one surface of the membrane; (b) dispensing liquid optics into the chamber; (c) vacuum bonding a transparent wafer on top of the chamber containing the liquid optics; And, (d) forming a cover frame having an actuator for deforming the membrane on the other surface of the membrane and a plurality of holes for changing the volume of the liquid optical body. The method of claim 10, In step (c), (c1) deforming the membrane forming the bottom surface of the chamber containing the liquid optical body and bonding the transparent wafer in a vacuum state; And, (c2) releasing the vacuum to restore the deformed membrane. The method of claim 11, Step (c1), And at least one of gravity and electrostatic forces to deform the membrane in the opposite direction to the transparent wafer. The method of claim 10, When the wall is formed on one surface of the membrane, forming a UV bonding layer on the wall surface; In the step (b), dispensing the liquid optical body to the lower surface of the UV bonding layer, In the step (c), the transparent wafer is vacuum-bonded to the wall using the UV bonding layer while the liquid optical body is dispensed, and UV coating is performed to shrink the UV bonding layer. How to make. The method of claim 12, Applying a UV bonding layer on the surface of the wall; In the step (c), vacuum bonding the transparent wafer to the wall using the UV bonding layer and performing UV coating to shrink the UV bonding layer. The method of claim 10, In step (a), (a1) etching the wafer to produce a wall forming a chamber of a predetermined shape; And, (a2) coupling the wafer to one surface of the membrane to form a chamber on the membrane. The method of claim 15, Step (a1), And a support part manufactured together with the wall to allow the liquid optical body to flow in a space between the bottom surface and a predetermined distance from the bottom surface of the chamber. The method of claim 15, Step (a1), And a support part which is spaced apart from a surface of the membrane by a predetermined distance to allow the liquid optical body to flow in a space between the membrane and one surface thereof together with the wall. The method of claim 10, In step (d), Forming the actuator in a predetermined region of the other surface of the membrane; And, Bonding the cover frame toward another surface of the membrane such that the actuator is positioned inside at least one of the plurality of holes. The method of claim 10, And when the plurality of chambers are formed on the membrane, dicing and separating the chambers for each chamber to collectively fabricate a plurality of variable focusing optical devices. In the manufacturing method of a varifocal optical device, Forming a wall constituting at least one chamber on the transparent wafer; Dispensing liquid optics in the chamber; Dispensing a liquid membrane having a specific gravity lower than that of the liquid optic onto the liquid optic; And, And when the liquid membrane is cured to form a membrane, forming a cover frame having an actuator for deforming the membrane and a plurality of holes for changing the volume of the liquid optical body. The method of claim 20, Forming a wall forming a chamber on the transparent wafer, Etching the wafer to produce the wall; And Bonding the wall to one surface of the transparent wafer to form a chamber having one surface of the transparent wafer as a bottom surface. The method of claim 21, Etching the wafer to produce the wall, And etching the wafer to collectively fabricate a support part together with the wall to allow the liquid optical body to flow in a space between the bottom surface and a distance from the bottom surface of the chamber. The method of claim 21, Etching the wafer to produce the wall, And etching the wafer to collectively fabricate a support part together with the wall to allow the liquid optical body to flow in a space between the membrane surface and a distance from the surface of the membrane. The method of claim 20, Forming a wall forming a chamber on the transparent wafer, Making grooves at the edges of the upper surface of the wall, Dispensing the liquid membrane, And dispensing the liquid membrane to the groove portion to cover the liquid optical body. The method of claim 20, And when the plurality of chambers are formed on the transparent wafer, dicing and separating the chambers for each chamber to collectively manufacture the plurality of variable focusing optical devices.

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