KR20070024814A - Apparatus for manufacturing micro lens and method for manufacturing micro lens - Google Patents

Abstract

A micro lens manufacturing device and method are provided to produce micro lenses of various shapes or a micro lens array at low cost within a short time by making a second lens-shaped polymer from a first lens-shaped polymer. A micro lens manufacturing device(100) is composed of a lower electrode(120); an insulating layer(104) formed on the lower electrode; an upper electrode(110) disposed separately from the insulating layer to dispose a first lens-shaped polymer(102) on the insulating layer; and a support substrate(106) formed under the lower electrode to support the lower electrode and the insulating layer. The lower or upper electrode is a plate electrode having a rectangular or circular shape.

Description

Apparatus for manufacturing micro lens and Method for manufacturing micro lens

1 is a cross-sectional view of a microlens manufacturing apparatus according to an embodiment of the present invention.

2A and 2B are perspective views showing examples of an upper electrode or a lower electrode used in the microlens manufacturing apparatus of the present invention.

3 is a cross-sectional view of a microlens manufacturing apparatus according to another embodiment of the present invention.

4 is a perspective view showing another example of an upper electrode or a lower electrode used in the microlens manufacturing apparatus of the present invention.

5 is a cross-sectional view of a microlens manufacturing apparatus according to still another embodiment of the present invention.

6 is a perspective view showing still another example of the upper electrode used in the microlens manufacturing apparatus of the present invention.

7 is a perspective view showing still another example of the upper electrode used in the microlens manufacturing apparatus of the present invention.

<Description of the symbols for the main parts of the drawings>

102: lens-shaped polymer 103: lens substrate

104: insulating layer 106: support substrate

110, 110a, 110b, 110c, 110d, 110e: upper electrode

120, 120a, 120b, 120c: lower electrode

114: saliva

BACKGROUND OF THE INVENTION Field of the Invention The present invention relates to a manufacturing apparatus and a manufacturing method of a microlens or a microlens array, and in particular, it is possible to easily manufacture various types of microlenses such as a lens having a large numerical aperture or an aspheric shape, and to a device and a manufacturing method thereof. will be.

In recent years, as the compact imaging apparatus is widely used, there is a growing demand for micro lenses having high performance. Background Art A lens replication technique using a mold or the like is widely known as a method of producing a microlens array, which is a microlens or an arrangement thereof, at low cost. Conventional methods for manufacturing or replicating micro lenses include a method using a modified LIGA (Lithographic-Galvanic) process, a method using isotropic etching of silicon, a method using a gray scale mask, and an electron beam (E-beam). Alternatively, there is a method of directly writing using a laser, a method of using precision machining of a mold, and a method of using reflow of a photosensitive material. For example, Korean Patent Application No. 2003-0024597 discloses manufacturing a micro lens array using a reflow process of a photosensitive layer. U. S. Patent No. 5,310, 623 also discloses the preparation of microlens replicas from photoresist materials using gray scale masks.

However, in the case of manufacturing a microlens (or microlens array) using a conventional general method, it is relatively expensive and time-consuming to manufacture a lens having a precisely desired shape, and difficulty in reflow process or mold making Due to the difficulty of the image, there is a limit to the manufacture of micro lenses of various shapes such as a large numerical aperture (Numerical Aperture) or aspherical lens.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object thereof is to provide a microlens manufacturing apparatus capable of easily manufacturing microlenses having various shapes such as having a large numerical aperture or an aspherical surface.

It is another object of the present invention to provide a microlens manufacturing method that can easily manufacture microlenses of various shapes.

In order to achieve the above technical problem, the microlens manufacturing apparatus according to the present invention, the lower electrode; An insulating layer and the insulating layer formed on the lower electrode; And an upper electrode spaced apart from the insulating layer to dispose a polymer having a primary lens shape on the insulating layer.

According to an embodiment of the present invention, the lower electrode may further include a support substrate for supporting the lower electrode and the insulating layer.

According to an embodiment of the present invention, the lower electrode or the upper electrode may be a plate-shaped electrode. In this case, the plate-shaped electrode may have a rectangular or circular planar shape.

According to an embodiment of the present invention, the lower electrode or the upper electrode may include a plurality of ring-shaped electrodes arranged concentrically. In this case, voltages of different potentials may be applied to the respective circular band electrodes.

According to an embodiment of the present invention, the lower surface of the upper electrode may be a concave curved surface having a curvature.

According to an embodiment of the present invention, pointed tips may be formed on the lower surface of the upper electrode. In this case, the needles can be configured to apply an electric field individually.

In order to achieve another object of the present invention, a method of manufacturing a micro lens according to the present invention comprises the steps of forming a polymer having a primary lens shape; Making the polymer into a secondary lens shape by applying a voltage to the lower electrode and the upper electrode while the polymer is disposed between the insulating layer formed on the lower electrode and the upper electrode; Curing the polymer of the secondary lens shape.

According to the method of manufacturing the microlens of the present invention, the lower electrode or the upper electrode may have a flat plate shape and a circular band shape as described in the microlens manufacturing apparatus described above, and the lower surface of the upper electrode may be a concave curved surface having a curvature. And needles may be formed on the bottom surface.

According to an embodiment of the invention, preferably, the primary lens-shaped polymer is formed by a reflow heat treatment process. Alternatively, the primary lens-shaped polymer may be formed by using droplets of polymer.

According to an embodiment of the invention, the secondary lens-shaped polymer can be used directly as a micro lens. According to another embodiment, the secondary lens-shaped polymer may be used in a circle for manufacturing a mold for forming a lens. In this case, the manufacturing method comprises the steps of: forming a mold by making the secondary lens-shaped polymer into a circle; The method may further include obtaining a micro lens using the mold. For example, the manufacturing method may include forming a plating layer on the polymer after the formation of the secondary lens shape polymer; Separating the plating layer from the polymer to obtain a mold; The method may further include obtaining a micro lens using the mold.

In the method of manufacturing a micro lens according to the present invention, a plurality of micro lens arrays (ie, micro lens arrays) are formed by forming a plurality of polymer patterns (polymer arrays) having a primary lens shape in the polymer forming step of the primary lens shape. ) Can be used to make.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. However, embodiments of the present invention may be modified in various other forms, and the scope of the present invention is not limited to the embodiments described below. Embodiments of the present invention are provided to more completely explain the present invention to those skilled in the art. Accordingly, the shape and size of elements in the drawings may be exaggerated for clarity, and the elements denoted by the same reference numerals in the drawings are the same elements.

1 is a cross-sectional view schematically showing a microlens manufacturing apparatus according to an embodiment of the present invention. Referring to FIG. 1, the apparatus 100 for manufacturing a microlens includes a lower electrode 120, an insulating layer 104 formed thereon, and an upper electrode 110 spaced apart from the insulating layer 104. The lower electrode 120 and the insulating layer 104 may be supported by the support substrate 106. The device 100 can be effectively used to make the polymer 102 having the primary lens shape into the desired secondary shape.

For example, the hemispherical polymer 102 obtained by reflow heat treatment of the polymer layer on the substrate 103 can be disposed between the insulating layer 104 and the upper electrode 110. After that, when voltage is applied to the upper electrode 110 and the lower electrode 120, the electrostatic force is generated in the polymer 102 by the upper electrode 110, the lower electrode 120, and the insulating layer 104. By this electrostatic force, the polymer 102 having the primary shape has a secondary shape having a different curvature or lens sag than before. In particular, since the polymer is attracted to the upper and lower electrodes by the electrostatic force, it is possible to easily produce a lens-shaped polymer (secondary lens-shaped polymer) having a large numerical aperture.

2A and 2B show examples of a plate-shaped upper electrode or lower electrode that can be used in a micro lens manufacturing apparatus. FIG. 2A shows a planar electrode having a rectangular planar shape that can be used as the upper electrode 110a or the lower electrode 120a. As shown in FIG. 2B, the upper electrode 110b or the lower electrode 120b may be a flat electrode having a circular planar shape. The upper electrode may be rectangular, and the lower electrode may be circular, or vice versa.

3 shows a micro lens manufacturing apparatus 200 according to another embodiment. The microlens manufacturing apparatus 200 of FIG. 3 uses the lower electrode 120c as shown in FIG. 4. That is, as shown in detail in FIG. 4, the lower electrode 120c of the manufacturing apparatus 200 includes a plurality of ring-shaped electrodes arranged in concentric circles. By configuring the lower electrode 120c with a plurality of circular band electrodes as described above, a lens having a more complicated shape can be easily manufactured. In particular, by applying voltages of different potentials to the respective circular band electrodes, the electrostatic force applied to the polymer 102 can be controlled differently according to the position. By changing the electrostatic force distribution in this manner, the polymer 102 can be made to have a very complicated lens shape (secondary lens shape). For example, when the lower electrode of the circular band electrodes is used, an inflection point may be formed on a portion of the upper surface of the polymer. In FIG. 3, only the lower electrode 120c is formed of a circular band electrode, but an upper electrode 110c of a circular band electrode may be used. Both the upper and lower electrodes may be formed as circular band electrodes.

5 is a cross-sectional view illustrating a microlens manufacturing apparatus 300 according to still another embodiment. This manufacturing apparatus 300 uses the upper electrode 110d as shown in FIG. As shown in FIGS. 5 and 6, the lower surface 112 of the upper electrode 110d is a concave curved surface having a curvature. In this case, by selecting an appropriate curvature of the lower surface 112 of the upper electrode, a desired curvature or numerical aperture of the lens can be easily obtained. In particular, the upper electrode 110d having the concave bottom surface 112 may apply uniform electrostatic force to the polymer 102. Thereby, a change in lens curvature that is uniform throughout can be obtained, and the numerical aperture of the lens can be precisely adjusted.

7 is a perspective view illustrating still another example of the upper electrode. Referring to FIG. 7, a plurality of pointed tips, that is, pointed tips 114, are formed on the upper electrode 110e. In particular, the needles 114 are formed on the lower surface 112 of the upper electrode 110e having a concave curved surface. Such needles 114 may locally concentrate an electric field to generate a locally concentrated electrostatic force on the surface of the polymer 102. Thereby, the polymer (secondary lens-shaped polymer) which has an uneven surface can be made. In addition, the upper electrode 110e may be configured such that a voltage may be individually applied to each needle 114. By doing so, the needles 114 can apply an electric field individually. In this case, the electrostatic force concentrated by the needles can be generated only in a specific area. Thus, it is possible to make secondary lens-like polymers in which certain areas have uneven surfaces and other areas do not have uneven surfaces.

Next, the method of manufacturing a micro lens using the micro lens manufacturing apparatus as mentioned above is demonstrated.

In order to produce a microlens according to the present invention, a polymer having a primary lens shape is first formed. The polymer having the primary lens shape may be formed by various methods. For example, it may be formed by a method of using a reflow through heating of a polymer pattern, a method of using a droplet, a method of using a mold obtained by using silicon isotropic etching, and the like. Preferably, for reduced manufacturing cost and time, the primary lens-shaped polymer is formed by a method that uses reflow of the polymer. For example, a polymer layer is formed on a substrate 103 such as a silicon substrate, and then patterned to form a polymer pattern. Thereafter, the polymer pattern is formed into a hemispherical primary lens shape through a reflow heat treatment process.

Thereafter, the polymer 102 having the primary lens shape (or the substrate 103 on which the polymer 102 is formed) is formed on the insulating layer 104 of the micro lens manufacturing apparatus 100, 200, 300 as described above. Place it. Thereafter, a voltage is applied to the upper electrode 110 and the lower electrode 120 to generate an electrostatic force on the polymer 102. This allows the polymer 102 to have a secondary shape with a desired numerical aperture (relatively large numerical aperture) and shape.

The secondary lens-shaped polymer thus formed can be used as a lens as long as the polymer material has light transmitting properties. However, as an alternative, the secondary lens-shaped polymer may be used in a circle for mold making. That is, after a mold is manufactured using a secondary lens-shaped polymer in a circle, the mold can be used to manufacture various types of micro lenses or an array thereof (micro lens array).

For example, after the formation of the secondary lens-shaped polymer, a Cr / Au layer is deposited several hundred micrometers thick on the secondary lens-shaped polymer to form a plating seed film for nickel plating. Thereafter, nickel plating is performed to form a nickel plating layer on the polymer. Then, the nickel plating layer is separated from the polymer to obtain a mold made of nickel. By carrying out the injection molding or hot embossing process of the polymer using this mold, a micro lens having a secondary lens shape of the above various forms is obtained. According to this, it is possible to easily manufacture a micro lens of a complicated shape such as a large numerical aperture or an aspherical surface at a reduced cost and a reduced process time.

In the method of manufacturing a micro lens according to the present invention, a plurality of micro lens arrays (ie, micro lens arrays) are formed by forming a plurality of polymer patterns (polymer arrays) having a primary lens shape in the polymer forming step of the primary lens shape. Can be readily used to make.

The present invention is not limited by the above-described embodiment and the accompanying drawings, but is intended to be limited by the appended claims, and various forms of substitution, modification, and within the scope not departing from the technical spirit of the present invention described in the claims. It will be apparent to those skilled in the art that changes are possible.

As described above, according to the present invention, a large numerical aperture lens or aspherical lens is formed by forming a secondary lens-shaped polymer from a primary lens-shaped polymer using a manufacturing apparatus having an upper electrode, a lower electrode, and an insulating layer. The microlenses or microlens arrays of various and complicated shapes can be easily manufactured at reduced time and cost.

Claims (16)

A lower electrode; An insulating layer and the insulating layer formed on the lower electrode; And an upper electrode spaced apart from the insulating layer to dispose a polymer having a primary lens shape on the insulating layer. The method of claim 1, And a support substrate for supporting the lower electrode and the insulating layer under the lower electrode. The method of claim 1, The lower electrode or the upper electrode is a microlens manufacturing apparatus, characterized in that the electrode of the flat plate shape. The method of claim 3, The flat plate-shaped electrode has a rectangular or circular plane shape, characterized in that the microlens manufacturing apparatus. The method of claim 1, And the lower electrode or the upper electrode includes a plurality of circular band-shaped electrodes arranged concentrically. The method of claim 5, A device for manufacturing a micro lens, wherein a voltage of a different potential is applied to each of the circular band electrodes. The method of claim 1, And a lower surface of the upper electrode is a concave curved surface having a curvature. The method of claim 1, Microneedle manufacturing apparatus, characterized in that a plurality of needles are formed on the lower surface of the upper electrode. The method of claim 8, And the needles are configured to apply an electric field individually. Forming a polymer having a primary lens shape; Making the polymer into a secondary lens shape by applying a voltage to the lower electrode and the upper electrode while the polymer is disposed between the insulating layer formed on the lower electrode and the upper electrode; And curing the polymer of the secondary lens shape. The method of claim 10, The forming of the polymer having a primary lens shape may include forming a polymer having a curved upper surface by reflow heat treatment of the polymer layer. The method of claim 10, The secondary lens-shaped polymer is a micro lens manufacturing method, characterized in that used directly as a micro lens. The method of claim 10, The secondary lens-shaped polymer is a micro lens manufacturing method, characterized in that used as a circle for manufacturing a mold for forming a lens. The method of claim 13, Forming a mold by making the secondary lens-shaped polymer into a circular shape; Micro lens manufacturing method comprising the step of obtaining a micro lens using the mold. The method of claim 13, Forming a plating layer on the secondary lens-shaped polymer; Separating the plating layer from the polymer to obtain a mold; Micro lens manufacturing method comprising the step of obtaining a micro lens using the mold. The method of claim 10, And forming a plurality of polymer patterns having a primary lens shape in the polymer forming step of the primary lens shape.

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