JPH0450804A - Manufacture of mirolens array - Google Patents

Abstract

PURPOSE:To obtain the micro lens arranged like an array at low cost by providing a hollow substrate having plural columnar holes arranged like an array, dripping a resin having prescribed viscosity from one face side into each hole, and forming a state that the resin does not flow down and the spherical shape is held. CONSTITUTION:A hollow substrate 6 having plural columnar holes 5 arranged like an array is provided, a resin 7 having prescribed viscosity consisting of a monomer or a partially polymerized sol-like liquid is dripped from one face side into each hole 5 of this hollow substrate 6, and a state that the resin 7 does not flow down to the lower part of the hole and a spherical shape A is held is formed. In such a state that the spherical shape A is held, a transparent substrate 8 is allowed to adhere closely from the face of the side in which the resin 7 is poured, and in its state, the resin 7 having the spherical shape A is polymerized and hardened, and thereafter, the hollow substrate 6 is peeled off. In such a way, the micro lens arranged like an array on the transparent substrate 8 can be obtained at low cost.

Description

[Detailed description of the invention] Industrial applications The present invention relates to a method for manufacturing a microlens array.

2. Description of the Related Art As a conventional method for manufacturing a microlens array, there is a method as shown in FIG. 2, for example. in this case,
First, a polymer film 2 containing a photopolymerizable substance is spin-coded on a substrate 1 (a). Next, 100 μm diameter, 125 μm diameter
Ultraviolet rays (
irradiate with UV). As a result, the photopolymerizable substance in the exposed polymer film 2 increases, and monomer flows from the unexposed area to the exposed area, causing the exposed area to expand and become spherical, forming a lens. (b).

Next, in order to stop the changing shape of the polymer film 2 and fix the lens shape, the entire polymer film 2 is exposed to light to react all unreacted components and stabilize the film. A synthetic resin microlens 4 can be manufactured by the following steps (C).

Problems to be Solved by the Invention In general, the focal length of the manufactured Micro 1 Nons varies depending on the amount of monomer, exposure conditions, film thickness, concentration, etc., and therefore it is very difficult to control the setting conditions. In the case of plastic microlenses, it is possible to make many microlenses of the same shape by using a mold for boat fishing, but it is also possible to make microlenses by the method described above (see Figure 2). In the case of manufacturing, it becomes extremely difficult to control the manufacturing conditions in order to manufacture lenses with the same specifications. For this reason, it is unfortunate that the greatest advantage of plastic lenses, which is low cost, cannot be achieved.

In addition, in order to manufacture microlenses used in 1-bit, 1-microlens type image scanners, etc., the diameter of the convex portion of each lens is approximately 0.1 mm, and it is difficult to manufacture a mold with a fine shape on this scale. Have difficulty.

Means for Solving the Problems Therefore, in order to solve such problems, the present invention provides a hollow substrate having a plurality of cylindrical holes arranged in an array, and each of the holes of the hollow substrate A resin having a constant viscosity made of a monomer or a partially polymerized sol-like liquid is dropped from one side of the hole, and this dripping prevents the resin from flowing down to the bottom of the hole and maintains the spherical shape. While maintaining the spherical shape, a transparent substrate is brought into close contact with the side on which the resin is poured, and the resin having the spherical shape is polymerized and cured while the transparent substrate is in close contact with the transparent substrate, and after this curing, the hollow substrate is By peeling, microlenses arranged in an array on the transparent substrate were produced.

Function: Therefore, the shape of the microlens is determined by the surface tension caused by the viscosity of the monomer or partially polymerized sol-like liquid, resulting in extremely excellent sphericity, which makes it easy to utilize light in simple operations. It is now possible to manufacture lenses with very high efficiency. Also, since the hollow substrate is peeled off after polymerization and curing, it can be used in the same way as a conventional stamper. Furthermore, the resin with a certain viscosity can be used on the hollow substrate. A large number of microlenses of the same shape can be manufactured simultaneously by simply dropping a drop into a hole, making it possible to manufacture them with high work efficiency and at low cost.

Example An embodiment of the present invention will be described based on FIG.

FIG. 1 shows the manufacturing process of the microlens array in this example. Hereinafter, a case will be described in which microlenses having a pitch and a lens diameter of about 0.1 mm are manufactured.

First, a hollow substrate 6 having a plurality of cylindrical holes S arranged in an array is provided (a). In this case, the diameter of the hole S is matched to the diameter of the microlens to be manufactured.

The material of the hollow substrate 6 is resin 7, which will be described later.
Use an inorganic material such as glass or metal that has excellent removability.

Next, resin 7 having a certain viscosity is poured into the holes 5 of the hollow substrate 6 (b). As the resin 7, a monomer or a partially polymerized sol liquid is used. The resin 7 is preferably made of a material that has high transparency and exhibits little volume shrinkage during polymerization; for example, acrylic resin can be used.

In this case, depending on the relationship between the diameter of the hole 5 and the viscosity of the resin 7,
A spherical surface A with a certain radius is generated. Since the spherical shape is determined only by surface tension, it is possible to obtain a material with extremely excellent sphericity. Then, the resin 7 does not flow down to the bottom of the hole 5 and maintains a constant spherical shape.

Next, while maintaining such a spherical shape, the transparent substrate 8 is
The spherical resin 7 is brought into close contact with the resin 7 from the poured side surface, and the spherical resin 7 is polymerized and cured using heat or light (C). By this polymerization and curing, the resin 7 having a spherical shape is bonded to the transparent substrate 8. In this case, as the transparent substrate 8, a material with good adhesion to the resin 7 is selected, and if necessary, the resin 7 and the transparent substrate 8
An adhesive layer (not shown) is provided between the two.

Finally, after the polymerization and curing, the hollow substrate 6 is peeled off from the transparent substrate 8, thereby making it possible to produce microlenses 9 arranged in an array on the surface of the transparent substrate 8 (d).

As mentioned above, the lens shape of the microlens 9 is determined by the surface tension due to the viscosity of the monomer or partially polymerized sol liquid, so the manufacturing conditions for the lens are simple and easy to control. Since the spherical shape of a lens created only by surface tension has excellent sphericity, it is possible to further improve the light utilization efficiency of the lens. Furthermore, since the hollow substrate 6 is peeled off after polymerization and hardening, it can be used in the same manner as a so-called conventional stamper.This allows the hollow substrate 6 to be used as a stamper as it is, which simplifies the work process. becomes possible. Further, by dropping a certain amount of resin 7 having a certain viscosity, a large number of microlenses having the same shape can be manufactured, so that work efficiency can be improved and costs can be reduced. Furthermore,
By providing the microlens 9 with the resin 7 having a constant viscosity, it is possible to change the focal length of the lens by changing its viscosity even if the lens diameter is constant.

Effects of the Invention The present invention provides a hollow substrate having a plurality of cylindrical holes arranged in an array, and injects a certain amount of monomer or partially polymerized sol-like liquid into each hole from one side of the hollow substrate. A resin having a viscosity of microlenses arranged in an array on the transparent substrate by polymerizing and curing the resin having the spherical shape while the transparent substrate is in close contact with the surface of the substrate, and peeling off the hollow substrate after the curing; Since the lens shape of the microlens is determined by the surface tension due to the viscosity of the monomer or partially polymerized sol-like liquid, it has extremely excellent sphericity. It is possible to produce lenses with extremely high light utilization efficiency through simple operations, and since the hollow substrate is peeled off after polymerization and curing, it can be used in the same way as a conventional stamper.
Furthermore, a large number of microlenses of the same shape can be simultaneously produced by simply dropping a resin having a certain viscosity into a hole in a hollow substrate, resulting in high working efficiency and low cost production.

[Brief explanation of the drawing]

FIG. 1 is a process diagram showing an embodiment of the present invention, and FIG. 2 is a process diagram showing a conventional example. 5... Hole, 6... Hollow board, 7... Resin, 8...
・Transparent substrate, 9...microlens

Claims (1)

[Claims] A hollow substrate having a plurality of cylindrical holes arranged in an array is provided, and a resin having a constant viscosity made of a monomer or a partially polymerized sol-like liquid is dropped into each hole of the hollow substrate from one side. By this dripping, the resin does not flow down to the bottom of the hole and maintains a spherical shape, and while maintaining this spherical shape, the transparent substrate is brought into closer contact with the surface on the side into which the resin has been poured, and the transparent substrate is Microlenses arranged in an array on the transparent substrate are manufactured by polymerizing and curing the resin having the spherical shape while the substrate is in close contact with each other, and peeling off the hollow substrate after the curing. A method for producing a microlens array characterized by.