KR101871046B1 - Liquid optical apparatus using electrowetting and electromagnetic force, and actuating method thereof - Google Patents

Abstract

A fluid optical apparatus using electrowetting and an electromagnetic force and a driving method thereof are disclosed. The fluid optical device includes a lens portion and a diaphragm portion coupled to an upper portion of the lens portion, wherein the lens portion includes an electromagnetic coil, an upper transparent conductive film coupled to the upper portion of the electromagnetic coil, A metal lens chamber having a liquid accommodation space formed therein and a transparent electroconductive liquid filled in the liquid accommodation space and serving as a lens, And a hydrophobic layer are sequentially stacked on the lower transparent conductive film and an insulating layer is formed between the lower transparent conductive film and the metal lens chamber. The diaphragm is filled in the rim of channels and channels through which the liquid flows, And a magnetic fluid having a light absorbing property to be performed.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluid optical apparatus using electrowetting and electromagnetism,

The present invention relates to a fluid optical apparatus using electrowetting and an electromagnetic force and a driving method thereof.

Electrowetting is a technique capable of artificially changing the contact angle by electrically generating an electric potential difference between an electrolyte and a solid surface by using an electrode coated with an insulating film to control the surface tension of the electrolyte. This technology is mainly used for developing liquid lenses and electronic displays.

On the other hand, auto focus is a camera optical system function that automatically focuses on a specific object. This function is largely divided into a contrast detection method and an infrared sensor method, and in recent years, a hybrid method combining infrared and contrast has been mainly used.

On the other hand, the iris is a device configured in the camera and controls the opening to control the amount of light passing through the lens. Adjusting the amount of light plays an important role in determining sharpness in shooting.

As demand for compact cameras has increased significantly, the development of fluid-based optics has become increasingly important. Fluid-based optics typically include a liquid lens and a liquid iris.

However, such a fluid-based optical apparatus has a problem that it is difficult to downsize and power consumption is high because an external separate driving member for driving is required.

Although the electrowetting method has a merit that the response speed is fast, since the conventional fluid-based optical device is combined with the fluid lens and the fluid irrigation made of separate elements, the size of the entire camera becomes large when the electrowetting technique is applied There is a problem.

The present invention provides a fluid optical device including both a fluid lens driven by electrowetting and a fluid stop driven by an electromagnetic force, and a driving method thereof.

According to an aspect of the present invention, a fluid optical apparatus using electrowetting and electromagnetic force is disclosed.

A fluid optical device according to an embodiment of the present invention includes a lens portion and a diaphragm portion coupled to an upper portion of the lens portion, wherein the lens portion includes an electromagnetic coil, a lower transparent conductive film A metal lens chamber coupled to an upper portion of the lower transparent conductive film and having a liquid accommodating space formed therein, and a transparent electroconductive liquid filled in the liquid accommodating space and serving as a lens, An insulating layer is formed between the lower transparent conductive film and the metal lens chamber, a dielectric layer and a first hydrophobic layer are stacked in this order from the inner peripheral surface of the lens chamber, A channel through which the liquid flows, and a light absorbing magnetic fluid which is filled in the rim of the channel and serves as a diaphragm. The.

The inner space of the lens chamber is formed to be inclined, and the area of the surface of the electroconductive liquid increases according to the inclination.

Wherein the lens chamber has a hollow cylindrical shape and the lens portion has a transparent insulating liquid filled in the remaining space of the space occupied by the electrically conductive liquid in the liquid containing space and a transparent insulating liquid between the lower transparent conductive film and the metal lens chamber And a voltage applying unit for applying a voltage to the lens.

When a voltage is applied between the lower transparent conductive film and the metal lens chamber, a curvature change occurs on the surface of the electroconductive liquid.

The magnitude of the voltage applied between the lower transparent conductive film and the metal lens chamber is adjusted to control the curvature change on the surface of the electroconductive liquid.

When a voltage is applied between the lower transparent conductive film and the metal lens chamber, the electroconductive liquid changes from a convex lens shape to a concave lens shape.

The diaphragm portion includes a disc-shaped intermediate transparent conductive film coupled to the upper portion of the metal lens chamber, a circular ring-shaped spacer coupled to the upper portion of the intermediate transparent conductive film, and a disc-shaped upper transparent conductive film coupled to the upper portion of the spacer Wherein the channel is formed in a space between the intermediate transparent conductive film and the upper transparent conductive film by a combination of the intermediate transparent conductive film, the spacer, and the upper transparent conductive film.

The diaphragm includes a second hydrophobic layer laminated on the inner surface of the upper transparent conductive film, and a voltage applying unit for applying a voltage to the electromagnetic coil.

When a voltage is applied to the electromagnetic coil, the magnetic fluid moves toward the center of the channel by the electromagnetic force of the electromagnetic coil.

The magnitude of the voltage applied to the electromagnetic coil is adjusted so that the distance of movement of the magnetic fluid in the direction of the center of the channel is controlled so that the size of the opening through which the light flows is adjusted.

According to another aspect of the present invention, there is provided an electro-optical device including an electromagnetic coil, a lower transparent conductive film, a metal lens chamber having a liquid containing space formed therein, a lens portion including a transparent electroconductive liquid filled in the liquid containing space, And a diaphragm including a channel through which the liquid flows, a magnetic fluid filled in the rim of the channel, and a light absorbing magnetic fluid serving as a diaphragm, is disclosed.

A method of driving a fluid optical device according to an embodiment of the present invention includes: receiving a lens change request signal; applying a voltage between the lower transparent conductive film and the metal lens chamber in response to input of the lens change request signal Receiving an iris adjustment request signal, and applying a voltage to the electromagnetic coil in response to the iris adjustment request signal.

The fluid optical device using electro-wetting and electromagnetic force according to the embodiment of the present invention includes both a fluid lens driven by electrowetting and a fluid stop driven by an electromagnetic force, It is possible to improve the performance of the optical device mounted on the optical device and to downsize the size of the optical device.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a schematic illustration of a structure of a fluid optical device using electrowetting and electromagnetic force according to an embodiment of the present invention.
2 is a diagram illustrating an ultra-small camera module to which the fluid optical device of FIG. 1 is applied.
3 is a diagram illustrating curvature variation of a lens of a fluid optical device according to an embodiment of the present invention.
4 is a diagram illustrating a diaphragm drive of a fluid optical device according to an embodiment of the present invention.
5 is a flowchart illustrating a method of driving a fluid optical device using electrowetting and electromagnetic force according to an embodiment of the present invention.

As used herein, the singular forms "a", "an" and "the" include plural referents unless the context clearly dictates otherwise. In this specification, the terms "comprising ", or" comprising "and the like should not be construed as necessarily including the various elements or steps described in the specification, Or may be further comprised of additional components or steps. Also, the terms "part," " module, "and the like described in the specification mean units for processing at least one function or operation, which may be implemented in hardware or software or a combination of hardware and software .

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

FIG. 1 is a schematic view illustrating a structure of a fluid optical device using electrowetting and electromagnetic force according to an embodiment of the present invention, and FIG. 2 is a view illustrating an ultra-small camera module to which the fluid optical device of FIG. 1 is applied. Hereinafter, the structure of the fluid optical device 100 using the electrowetting and electromagnetic force according to the embodiment of the present invention will be described with reference to FIG. 1, with reference to FIG.

Referring to FIG. 1, a fluid optical device 100 according to an embodiment of the present invention includes a lens unit 110 and a diaphragm unit 150. For example, as shown in FIG. 2, a fluid optical device 100 according to an embodiment of the present invention includes a cylindrical lens portion 110 and a disk-like diaphragm portion 150 coupled to the lens portion 110, And may be formed in a cylindrical shape. The fluid optical device 100 may be coupled to the housing 200 as shown in FIG. 2 in order to apply the ultra-small camera module.

1, the fluid optical device 100 includes an electromagnetic coil 120, a lower transparent conductive film 130, a metal lens chamber 140, an intermediate transparent conductive film 160, A spacer 165, and an upper transparent conductive film 170 may be combined.

That is, the lower transparent conductive film 130 is coupled to the upper portion of the electromagnetic coil 120. Here, the electromagnetic coil 120 is configured to move a magnetic fluid (FerroFluid) 151 to be described later. The electromagnetic coil 120 has a disk-shaped lower transparent conductive film (Not shown). That is, when a voltage is applied to the electromagnetic coil 120, an electromagnetic field is generated in the electromagnetic coil 120, so that the magnetic fluid 151 can react. In order to apply a voltage to the electromagnetic coil 120, the fluid optical device 100 may include a voltage applying unit (not shown) for applying a voltage to the electromagnetic coil 120. The lower transparent conductive film 130 may be an ITO (Indium Tin Oxide) glass having electrical conductivity.

A cylindrical metal lens chamber 140 having a metal material and hollow is coupled to the upper portion of the lower transparent conductive film 130. Here, the metal lens chamber 140 has a liquid accommodation space formed inside the hollow, which becomes wider as it goes from the lower part to the upper part. The liquid containing space is filled with a transparent insulating liquid (e.g., oil) 111 occupying the remaining space of the space occupied by the transparent electrically conductive liquid (for example, water) 111 and the electrically conductive liquid 111, ) 112 may be filled. 1, an insulating layer 141 and a hydrophobic layer 142 are sequentially formed on the inner peripheral surface of the metal lens chamber 140 from the inner peripheral surface of the lens chamber 130 And the insulating layer 141 may be formed between the metal lens chamber 140 and the lower transparent conductive layer 130 for insulation from the lower transparent conductive layer 130. A voltage may be applied between the metallic lens chamber 140 of the metallic material and the lower transparent conductive film 130 having electrical conductivity and the fluid optical device 100 may include a metal lens chamber 140 and a lower transparent conductive film 130 And a voltage application unit 115 for applying a voltage between the electrodes. With such a configuration, the lens portion 110 of the fluid optical device 100 according to the embodiment of the present invention can be formed.

A disk-shaped intermediate transparent conductive film 160 is coupled to an upper portion of the lens unit 110, that is, an upper portion of the metal lens chamber 140, and a circular ring-shaped spacer 160 is formed on the intermediate transparent conductive film 160. The upper transparent conductive film 170 is bonded to the upper surface of the spacer 165. The upper transparent conductive film 170 is formed on the upper surface of the spacer 165, At this time, the upper edge of the metal lens chamber 140 and the edge of the intermediate transparent conductive film 160 may be attached by attaching the optical adhesive to the metal lens chamber 140 and the intermediate transparent conductive film 160. The space between the intermediate transparent conductive film 160 and the upper transparent conductive film 180 formed by the combination of the intermediate transparent conductive film 160, the spacer 165 and the upper transparent conductive film 170 And a ferrofluid 151 having a light absorbing function to serve as a diaphragm can be filled in the rim of the channel 155. [ 1, a hydrophobic layer 193 may be laminated on the upper surface of the channel 155, that is, the inner surface of the upper transparent conductive film 170. At this time, the magnetic fluid 151 can move in the center direction from the rim of the channel 155 by the electromagnetic field generated by the electromagnetic coil 120 to which the voltage is applied, as described above. With this configuration, the diaphragm 150 of the fluid optical device 100 according to the embodiment of the present invention can be formed.

Up to now, the structure of the fluid optical device 100 according to the embodiment of the present invention has been described with reference to Figs. 1 and 2. Fig. A method of driving the fluid optical device 100 shown in FIG. 1 will be described with reference to FIGS. 3 and 4. FIG.

FIG. 3 is a diagram illustrating curvature change of a lens of a fluid optical device according to an embodiment of the present invention. FIG.

3, a transparent electroconductive liquid 111 serving as a lens filled in a liquid containing space is first formed on the surface (that is, an insulating liquid) by the surface tension of the liquid, (I.e., the interface between the substrate 110 and the substrate 112) is rounded. That is, the electrically conductive liquid 111 corresponds to the lens of the fluid optical device 100 according to the embodiment of the present invention, and has the form of a convex lens in a natural state.

1, the inner space of the metal lens chamber 140 is inclined so that the inner space of the metal lens chamber 140 is widened from the lower part to the upper part. 3, the surface of the electrically conductive liquid 111 may have a larger area, and the area of the surface of the electrically conductive liquid 111 may be changed depending on the inclination angle of the inner circumferential surface of the metal lens chamber 140, Can vary. Of course, this is only one embodiment, and the inner peripheral surface of the metal lens chamber 140 may be formed vertically so as not to be inclined.

Thereafter, when a voltage is applied between the metal lens chamber 140 and the lower transparent conductive film 130, a curvature change occurs on the surface of the conductive liquid 111. 2, as the voltage is applied between the metal lens chamber 140 and the lower transparent conductive film 130, the convex lens-shaped electroconductive liquid 111 is subjected to the electro-wetting principle It can be changed into a concave lens shape. Of course, this is only one example. For example, the magnitude of the voltage applied between the metal lens chamber 140 and the lower transparent conductive film 130 may be finely adjusted, so that the electroconductive liquid 111, The curvature of the surface of the substrate may be finely adjusted.

4 is a diagram illustrating the diaphragm driving of the fluid optical device according to the embodiment of the present invention.

4, when a voltage is applied to the electromagnetic coil 120 described above with reference to FIG. 1, the magnetic fluid 151 having a light absorbing property, which functions as a diaphragm filled in the rim of the channel 155, , The size of the opening of the fluid optical device 100 into which light is introduced can be gradually reduced by moving toward the center of the channel 155 as shown on the right side of Fig.

1, when a voltage is applied to the electromagnetic coil 120 coupled to the lower portion of the lens unit 110, the magnetic fluid 151 filled in the rim of the channel 155 is discharged to the outside of the electromagnetic coil 120 It can move a certain distance in the direction of the center of the channel 155 by the electromagnetic force. Thereafter, when the voltage applied to the electromagnetic coil 120 is released, the magnetic fluid 151 can move to the rim of the in-situ channel 155.

For example, the magnitude of the voltage applied to the electromagnetic coil 120 is finely adjusted so that the distance by which the magnetic fluid 151 moves toward the center of the channel 155 is finely adjusted, The size of the opening of the optical device 100 can be adjusted.

5 is a flowchart illustrating a method of driving a fluid optical device using electrowetting and electromagnetic force according to an embodiment of the present invention. 5, the fluid optical device 100 may include functional components of a general camera, such as a user input means such as a shutter, a photographing mode setting button, etc. Hereinafter, the fluid optical device 100 will be described, A flow chart will be described.

In step S510, the fluid optical device 100 receives the lens change request signal through the user input means.

In step S520, the fluid optical device 100 applies a voltage between the metal lens chamber 140 and the lower transparent conductive film 130 according to the input of the lens change request signal.

At this time, as a voltage is applied between the metal lens chamber 140 and the lower transparent conductive film 130, a curvature change occurs on the surface of the electrically conductive liquid 111 serving as a lens. For example, the magnitude of the voltage applied between the metal lens chamber 140 and the lower transparent conductive film 130 can be finely adjusted, and thus the curvature of the surface of the electrically conductive liquid 111 can be finely adjusted .

In step S530, the fluid optical apparatus 100 receives the iris adjustment request signal through the user input means.

In step S540, the fluid optical device 100 applies a voltage to the electromagnetic coil 120 coupled to the lower portion of the lens unit 110 according to the input of the iris adjustment request signal. For example, the iris adjustment request signal may include electromagnetic force magnitude information corresponding to the aperture size selected by the user.

At this time, as the voltage is applied to the diaphragm electromagnetic coil 120, the magnetic fluid 151 acting as a diaphragm moves in the channel 155. For example, when a voltage is applied to the electromagnetic coil 120 coupled to the lower portion of the lens unit 110, the magnetic fluid 151 filled in the rim of the channel 155 is attracted by the electromagnetic force of the electromagnetic coil 120, In the direction of the center of FIG.

It will be apparent to those skilled in the art that various modifications, additions and substitutions are possible, without departing from the spirit and scope of the invention as defined by the appended claims. Should be regarded as belonging to the following claims.

100: Fluid optical device
110:
120: electromagnetic coil
130: lower transparent conductive film
140: metal lens chamber
150:
160: intermediate transparent conductive film
165: spacer
170: upper transparent conductive film

Claims (11)

A fluid optical device using electrowetting and electromagnetic force,
A lens portion; And
And a diaphragm coupled to an upper portion of the lens unit,
The lens unit includes:
Electromagnetic coil;
A lower transparent conductive film coupled to the upper portion of the electromagnetic coil and having electrical conductivity;
A metal lens chamber coupled to an upper portion of the lower transparent conductive film and having a metallic material in which a liquid containing space is formed;
A transparent electroconductive liquid filled in the liquid containing space and serving as a lens;
A transparent insulating liquid filled in the remaining space of the space occupied by the electrically conductive liquid in the liquid containing space; And
And a voltage application unit for applying a voltage between the lower transparent conductive film and the metal lens chamber,
A dielectric layer and a first hydrophobic layer are stacked in this order from the inner circumferential surface of the metal lens chamber,
The insulating layer is formed between the lower transparent conductive film and the metal lens chamber,
The diaphragm portion,
An intermediate transparent conductive film in the form of a disk and coupled to an upper portion of the metal lens chamber;
A circular ring-shaped spacer coupled to an upper portion of the intermediate transparent conductive film;
An upper transparent conductive film in the shape of a disk coupled to the upper portion of the spacer;
A channel formed in a space between the intermediate transparent conductive film and the upper transparent conductive film by a combination of the intermediate transparent conductive film, the spacer, and the upper transparent conductive film, the channel through which the liquid flows;
A light absorbing magnetic fluid filled in the rim of the channel and serving as a diaphragm;
A second hydrophobic layer laminated on the inner surface of the upper transparent conductive film; And
And a voltage applying unit for applying a voltage to the electromagnetic coil.
The method according to claim 1,
Wherein the liquid accommodation space is formed so as to be wider from the lower part to the upper part in the inside of the metal lens chamber, the inner circumferential surface of the metal lens chamber is inclined, and the surface area of the electrically conductive liquid increases according to the inclination Lt; / RTI >
The method according to claim 1,
Wherein the metal lens chamber has a hollow cylindrical shape.
The method according to claim 1,
Wherein when a voltage is applied between the lower transparent conductive film and the metal lens chamber, a curvature change occurs on the surface of the electroconductive liquid.
The method according to claim 1,
Wherein a magnitude of a voltage applied between the lower transparent conductive film and the metal lens chamber is adjusted to control a curvature change on a surface of the electroconductive liquid.
The method according to claim 1,
Wherein when the voltage is applied between the lower transparent conductive film and the metal lens chamber, the electroconductive liquid changes from a convex lens shape to a concave lens shape.
delete delete The method according to claim 1,
Wherein when the voltage is applied to the electromagnetic coil, the magnetic fluid moves toward the center of the channel by the electromagnetic force of the electromagnetic coil.
The method according to claim 1,
Wherein the magnitude of the voltage applied to the electromagnetic coil is adjusted so that the distance of movement of the magnetic fluid in the direction of the center of the channel is adjusted so that the size of the opening through which the light is introduced is adjusted.



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