CN106772715B

CN106772715B - Preparation method of curved bionic compound eye

Info

Publication number: CN106772715B
Application number: CN201710080163.9A
Authority: CN
Inventors: 郝永平; 刁晓蕾; 李伦; 刘凤丽
Original assignee: Shenyang Ligong University
Current assignee: Shenyang Ligong University
Priority date: 2017-02-15
Filing date: 2017-02-15
Publication date: 2020-03-31
Anticipated expiration: 2037-02-15
Also published as: CN106772715A

Abstract

A method for manufacturing a curved bionic compound eye comprises the steps of injecting liquid photopolymer into a planar compound eye mold to be solidified, taking out the liquid photopolymer to obtain a micro-lens array mold, and forming a plurality of hemispherical pits on one side of a plane. The center of the upper surface of the plane compound eye mould is provided with a plurality of holes. Every is downthehole all places a upper surface and is the semicircle sphere recess formed part of semicircle ball, and the last semicircle ball of semicircle sphere recess formed part covers the hole. And injecting an organic silicon material into the spherical mould until the organic silicon material is solidified, and taking out the spherical mould to obtain the curved bionic compound eye. The spherical mould comprises a spherical front groove and a spherical front convex cover, and convex surfaces are arranged in parallel towards one side. The microlens array mould is provided with a plurality of semi-spherical concave pits, one surface of each semi-spherical concave pit is outwards fixed at the center of the spherical front groove, and the space between the spherical front groove and the spherical front convex cover is a curved surface bionic compound eye forming space. The invention greatly reduces the difficulty and cost of mould processing, and the mould casting method is simple and convenient to operate.

Description

Preparation method of curved bionic compound eye

Technical Field

The invention belongs to the technical field of optics, and particularly relates to a preparation method of a curved bionic compound eye, which is used for manufacturing an optical imaging system.

Background

With the continuous development of scientific technology, optical imaging systems are applied in various fields. The compound eye has the structural characteristics of simultaneous imaging of multiple channels and curved surface distribution of sub-eyes and high data centralized processing capacity of a neural network, so that the compound eye can complete the tasks of detection, positioning, super-resolution reconstruction, high-precision three-dimensional target measurement and the like of a high-sensitivity moving target under the conditions of short distance and large visual field, and the defects of small visual field, low reliability, high power consumption, inconvenience in operation and the like of binocular vision are overcome to a great extent, so that the compound eye has great potential application value in the fields of military, medical treatment, aviation and the like.

At present, most bionic compound eyes are of a planar structure, but the general defects of the planar bionic compound eyes are that the field angle is not large enough, the structure of the small-sized curved bionic compound eye is complex to manufacture, photoresist hot melting and laser direct writing photoetching methods are generally adopted, the methods not only need long time, but also have high cost and low success rate, and the manufactured samples have low precision.

Disclosure of Invention

The invention aims to provide a preparation method of a curved bionic compound eye, aiming at the defect that the existing bionic compound eye is of a planar structure, and the preparation method is simple to process, low in cost and capable of being used repeatedly.

The technical scheme is as follows:

the method for manufacturing the curved bionic compound eye comprises the following steps:

1) and injecting liquid photopolymer into the plane compound eye mould, irradiating the liquid photopolymer to be solidified by using a purple light lamp, and taking out the liquid photopolymer to obtain the micro-lens array mould, wherein a plurality of semi-spherical pits are formed in one side plane.

The upper surface of the plane compound eye mould is provided with a flat plane compound eye mould groove, the center of the plane compound eye mould groove is provided with a plurality of holes, the plurality of holes are divided into a plurality of concentric circular arrangement, and the center of the innermost circular ring is also provided with a hole;

the edge of each hole is circular, and a sphere is placed in each hole and used as a semi-sphere groove forming part. The diameter of the ball is equal to the diameter of the hole.

) And injecting an organic silicon material into the spherical mould, solidifying, and taking out to obtain the curved bionic compound eye.

The spherical mould comprises a spherical front groove and a spherical front convex cover, and convex surfaces are arranged in parallel towards one side.

The microlens array mold has a face of the plurality of semi-spherical depressions outwardly fixed at the center of the spherical front groove.

The space between the spherical front groove and the spherical front convex cover is a curved surface bionic compound eye forming space. The spherical front groove and the spherical front convex cover may have the same curvature.

The advantages are that:

the invention greatly reduces the difficulty and cost of die processing. Compared with the traditional photoresist hot melting method, the mold casting method has the advantages of simple and convenient operation, low cost, high success rate and capability of recycling the manufactured mold.

Description of the drawings:

FIG. 1 is a schematic structural diagram of a curved bionic compound eye according to the present invention.

Fig. 2 is a flow chart of a fabrication process of the present invention.

Fig. 3 is a schematic structural view of a planar compound eye mold.

FIG. 4 is a schematic structural diagram of a plane compound eye mould for placing steel balls.

Fig. 5 is a schematic structural view of a planar compound eye mold placed in an auxiliary mold.

Fig. 6 is a schematic view of the structure of a spherical front groove.

Fig. 7 is a schematic structural view of a pressure injector used in cooperation with a spherical mold.

FIG. 8 is a schematic view of a structure with edges on the substrate removed.

The specific implementation mode is as follows:

example 1

1) drawing the structure diagrams of the plane compound eye mould 1, the spherical mould 8 and the auxiliary mould 5 by using three-dimensional modeling software.

The plane compound eye mould 1 is cylindrical, a flat plane compound eye mould groove 2 is formed in the upper surface of the plane compound eye mould 1, a plurality of holes 3 are formed in the center of the plane compound eye mould groove 2, the edge of each hole 3 is circular, the lower portion of each hole 3 is cylindrical, and the axes of the plurality of holes 3 are parallel to the axis of the plane compound eye mould 1. The plane compound hole mould groove 2 is circular.

The plurality of holes 3 are divided into a plurality of concentric circular arrangements, and a hole 3 is also provided in the center of the innermost circular ring. In this example, 225 holes 3 are uniformly distributed. The plurality of holes 3 are blind holes.

The spherical mould 8 comprises a spherical front groove 6 and a spherical front convex cover 9 which have the same curvature and are fixedly connected in an edge sealing manner, and convex surfaces are arranged in parallel towards one side.

The space between the spherical front groove 6 and the spherical front convex cover 9 is a curved surface bionic compound eye forming space.

Can be fixed with supplementary mould 5 in the plane compound eye mould 1 outside, supplementary mould 5 is the disc that has supplementary mould recess 14, and plane compound eye mould 1 sets up in supplementary mould recess 14, and the upper edge of plane compound eye mould recess 2 is the parallel and level with supplementary mould recess face 14, because the diameter of plane compound eye mould 1 is 1cm, is equipped with great supplementary mould 5 in the outside and conveniently pours into NOA61 (liquid photopolymer).

) Placing a metal material, aluminum in the embodiment, on a precision machine tool, and machining a plane compound eye mould 1 and an auxiliary mould 5 according to the method 1).

And (3) printing the spherical mould 8 by using a 3D printer, wherein the spherical mould 8 can be made of PLA material.

) All place a hemisphere recess formed part 4 that the upper surface is the hemisphere in every hole 3, the last hemisphere of hemisphere recess formed part 4 can cover hole 3, and the diameter of last hemisphere in this embodiment is the same with the diameter of hole 3, and hemisphere recess formed part 4 is the steel ball of ball shape, and diameter 0.5mm, the diameter of hole 3 also is 0.5 mm.

The NOA61 was poured into the plane fly-eye mold 1 and the auxiliary mold 5 in which the steel balls were arranged, and the liquid NOA61 was irradiated with the UV lamp 10, and the curing was repeated several times.

Carefully removing the cured NOA61 with tweezers, and removing the molded part of the auxiliary mold 5 to leave only the film of the molded part on the planar fly-eye mold 1, wherein the film is the microlens array mold 7, one side of the microlens array mold 7 is a plane, and the plane on the other side of the microlens array mold 7 is provided with 225 hemispherical pits.

One side of the plane of the micro lens array mould 7 is stuck in the center of the bottom of the spherical front groove 6 prepared in advance by using an instant curing adhesive (epoxy resin AB glue), and 225 semi-spherical pits on the other side of the micro lens array mould 7 are upward.

) Fully mixing the PDMS body (organic silicon material) and the curing agent according to the mass ratio of 10:1, completely discharging bubbles by adopting vacuum pumping, transferring the mixture into a pressure injector, and slowly injecting the PDMS body and the curing agent into the spherical mold 8 from an injection hole of the spherical front convex cover 9. The PDMS body (organic silicon material) and the curing agent are produced by Dow Corning USA.

The bubbles are completely discharged by vacuumizing, so that the imaging quality of a finished product is prevented from being influenced by the bubbles, and the curing time of the PDMS body is saved.

Curing the mixture in a constant temperature oven at 65 ℃ for 10 hours until the PDMS body and the curing agent are completely cured.

) And shaking up the release agent (Japanese tricolor SP-751 anilox roller cleaning agent), standing for 3-5 minutes, slowly pouring the release agent into the spherical mold 8, and standing for 15-20 minutes to ensure that the mold and the release agent are fully contacted.

In this example, the mixture was shaken up and allowed to stand for 3 minutes, and then a mold release agent was slowly poured into the mixture and allowed to stand for 15 minutes.

The film made of PDMS and curing agent is removed from the spherical mold 8 with tweezers, and the edges of the microlens array mold 7 are carefully removed, so as to obtain a uniform curved bionic compound eye 15.

The curved bionic compound eye 15 comprises a substrate and a micro-lens array 11 (compound eye) on the front surface of the substrate, and an excessive edge 12 which is flush with the micro-lens array 11 on the front surface of the substrate can be removed. The thickness of the formed substrate after removal of the excess edge 12 was 1 mm.

The present invention is suitable for making miniature homogeneous arrays, so that the imaging quality is not greatly affected, and the microlens arrays 11 are uniformly arranged on the forming substrate 13 in an annular arrangement. The uniform curved surface micro-lens array structure has a wider field angle range than that of a uniform plane micro-lens array structure.

Has good light transmission, elasticity and chemical inertness. The manufactured curved microlens array sample is a uniform and transparent film.

The steel ball fills the plane compound eye mould 1, and fills the blank that the small-size spherical groove can not be machined.

The liquid NOA61 is a clear, colorless, liquid photopolymer that is curable under uv light. The use of the NOA61 glue eliminates the need for pre-mixing, drying or heat curing operations that are typically required in other optical bonding systems.

The liquid release agent was a japanese tricolor SP-751 anilox roll cleaner. The purpose is to be able to easily peel off the NOA61 mold from the PDMS, resulting in a complete microlens array mold 7.

Example 2

Example 2 is substantially the same as example 1 except that: and shaking the release agent uniformly, standing for 5 minutes, slowly pouring the release agent into the spherical mold 8, and standing for 20 minutes.

Example 3

Example 3 is essentially the same as example 1, except that: and shaking the release agent uniformly, standing for 4 minutes, slowly pouring the release agent into the spherical mold 8, and standing for 18 minutes.

Claims

1. The method for manufacturing the curved bionic compound eye is characterized by comprising the following steps of:

1) injecting liquid photopolymer into the plane compound eye mould (1) to solidify and take out to obtain a micro-lens array mould (7), wherein a plurality of semi-spherical pits are formed in the plane on one side;

the upper surface of the plane compound eye mould (1) is provided with a smooth plane compound eye mould groove (2), and the center of the plane compound eye mould groove (2) is provided with a plurality of holes (3);

a semi-sphere groove forming piece (4) with a semi-sphere upper surface is arranged in each hole (3), and a semi-sphere of the semi-sphere groove forming piece (4) covers the hole (3);

2) injecting an organic silicon material into the spherical mould (8), solidifying, and taking out to obtain a curved bionic compound eye (15);

the spherical mould (8) comprises a spherical front groove (6) and a spherical front convex cover (9), and convex surfaces are arranged in parallel towards one side;

the side of the micro lens array mould (7) with a plurality of semi-spherical concave pits is fixed at the center of the spherical front groove (6) outwards,

the space between the spherical front groove (6) and the spherical front convex cover (9) is a curved surface bionic compound eye forming space.

2. The method for manufacturing the curved bionic compound eye according to claim 1, characterized by comprising the following steps:

the plurality of holes (3) are divided into a plurality of concentric circular arrangements.

3. The method for manufacturing the curved bionic compound eye according to claim 2, characterized by comprising the following steps: a hole (3) is also provided in the centre of the innermost ring.

4. The method for manufacturing the curved bionic compound eye according to claim 1, characterized by comprising the following steps:

the edges of the holes (3) are circular, the semi-sphere groove forming piece (4) is a sphere, and the diameter of the sphere is equal to that of the holes (3).

5. The method for manufacturing the curved bionic compound eye according to claim 1, characterized by comprising the following steps:

the liquid photopolymer is NOA 61;

the silicone material is PDMS.

6. The method for manufacturing the curved bionic compound eye according to claim 1, characterized by comprising the following steps:

the curvature of the spherical front groove (6) is the same as that of the spherical front convex cover (9).

7. The method for manufacturing the curved bionic compound eye according to claim 4, characterized by comprising the following steps:

225 holes (3) are formed, the diameter of the round ball is 0.5mm, and the planar compound eye die (1) is cylindrical and has the diameter of 1 cm.