CN1556444A

CN1556444A - Preparation method of three dimensional photon crystal and its device

Info

Publication number: CN1556444A
Application number: CNA2004100030075A
Authority: CN
Inventors: 守刘; 刘守; 张向苏; 刘影
Original assignee: Xiamen University
Current assignee: Xiamen University
Priority date: 2004-01-09
Filing date: 2004-01-09
Publication date: 2004-12-22
Anticipated expiration: 2024-01-09
Also published as: CN100406931C

Abstract

The invention relates to a method and device of preparing 3D photon crystals by holography, making beam expansion and space filter on a laser light, then turning the laser light into a beam-expanded parallel light to irradiate a grating plate and then generate 4-beam optical interference on the grating plate, placing a recording dry plate in the optical interference region, and then exposing and developing. It is provided with a laser, a beam-expanding and space filtering apparatus, a collimating lens, a grating plate and a holographic recording dry plate, and the beam-expanded parallel light forms 4-beam optical interference on the grating plate. It only needs a single laser light beam and a grating plate to generate 4 light beams and the fourth light beams run in expected directions. The four light beams converge and mutually interfere in the space to generate a 3D figure with a periodically-varying optical strength. It uses a photosensitive material to generate a 3D lattice structure with a periodically-varying refractive index. As long as the ratio of two refractive indexes in the lattice structure is large enough, it can generate a photon forbidden band and thus this photosensitive material can act as photo crystals. If the photoetching hectograph acts as the recording material, it can also take the recorded structure as a template and use a high-refractive index material to make photo crystals.

Description

Method for manufacturing three-dimensional photonic crystal and device thereof

Technical field

The present invention relates to a kind of method and device thereof for preparing three-D photon crystal with holographic method.

Background technology

Photonic crystal is the artificial crystal that is formed by the dielectric substance periodic arrangement of different refractivity.Different with mineral crystal diffraction X ray, the photonic crystal diffraction be visible light and near infrared ray.Similar semiconductor material has the energy forbidden band to electronics, and photonic crystal has the optical band gap to light wave, and promptly the light wave of frequency in a certain scope can't pass through specific photonic crystal, and be reflected fully.This characteristic makes photonic crystal that many important use be arranged, for example prepare high efficient LED, photonic crystal fiber, photon crystal laser etc., and in systems such as optical communication, all-optical network, fiber laser, semiconductor laser and device, obtain important application.

The method for making of photonic crystal has multiple, as the method that is layering, colloid self-organization method, and various etching, plate-making technology, comprises technology such as the dull and stereotyped etching of X ray, ion beam etching, glancing angle deposition and light modulated electrochemical etching.These methods are the preparation process complexity not only, and is difficult to obtain the photonic crystal of multilayer.(seen document MCampbell, D N Sharp, M T Harrison what report, et al, Fabrication of photonic crystals for the visiblespectrum by holographic lithography, Nature, 2000,404:53-56.) in the holographic technique, the preparation process of four bundle interference of light technology is the fastest, but currently used four bundle laser are with many optical elements beam of laser to be divided into four the tunnel, through half-wave plate the polarization direction of each light path is changed into same direction again, and then each Shu Guang is expanded bundle, collimates.

Summary of the invention

Used a kind of device when the present invention aims to provide a kind of good stability, equipment method for preparing three-D photon crystal simple, easy and simple to handle and preparation thereof.

The said method for manufacturing three-dimensional photonic crystal of the present invention is through expanding bundle and spatial filtering with laser, become the directional light that expands bundle again, the directional light that expands after restrainting is shone on the grating version, after the grating version, produce the 4 bundle interference of light, place the holographic recording dry plate at interference region, behind exposure imaging, promptly get three-D photon crystal.

In order to prepare three-D photon crystal, the present invention provides a kind of device for preparing three-D photon crystal, it is provided with laser instrument, is provided with 1 successively and expands bundle and spatial filter, 1 collimation lens, 1 grating version and 1 holographic recording dry plate on the light path of laser instrument output laser.Said laser is to holographic recording dry plate sensitivity, and for example 442nm and 458nm wavelength are to photoetching hectograph sensitivity.Said grating version forms the 4 bundle interference of light to the directional light that expands after restrainting.

The present invention adopts optical element seldom, only needs single beam laser and a grating version just can produce four bundle light, and the direction operation to expect.Four bundle light converge the back and interfere with each other at free space, have produced the periodically variable three-dimensional picture of light intensity.With photochromics graphic recording is got off, just in material, produced the three-dimensional lattice structure of refractive index cycle variation.As long as the ratio of two kinds of refractive indexes in the crystalline network is big (as reaching more than 2.1) enough, just can produce forbidden photon band, this material just can be used as photonic crystal.If with photoresist dry plate (the being called for short the photoetching hectograph) material that keeps a record, also the structure of noting can be used as masterplate, turn over high-index material and make photonic crystal.And its preparation process is simple.

Description of drawings

Fig. 1 is the structural representation of three-D photon crystal preparation facilities embodiment.

Fig. 2 is the structural representation of the grating version of three-D photon crystal preparation facilities embodiment.

Fig. 3 is 4 beam interferometer light direction synoptic diagram.

Embodiment

As shown in Figure 1, a branch of wavelength of laser instrument 1 output is to the laser of record dry plate 5 sensitivities (as 442nm and 458nm wavelength to photoetching hectograph sensitivity), after expanding bundle wave filter 2 and expanding bundle and spatial filtering, by lens 3 collimations, shines then on the grating version 4.As shown in Figure 2, three gratings 41 have been made above the grating version 4.At the center of grating version 4 white space 42 is arranged, shape is fixedly requirement not, can be square, circle or triangle etc.Three gratings 41 differ 120 ° round the central area between each grating.The light that sees through the grating version has formed four bundles (referring to Fig. 3), and a branch of central light beam sees through and propagates along optical axis from the white space 42 at grating version 4 centers (as Fig. 2 square), and traffic direction is without any change; Three-beam is formed by the first-order diffraction light of three gratings 41 respectively in addition, and traffic direction and optical axis form an angle theta, and this angle is the first order angle of diffraction of grating.Because the identical and symmetric offset spread of grating constant of three gratings, the three beams diffraction light departs from original traffic direction with identical angle θ, turns the direction to central light beam.The four bundle light (central light beam and three diffracted beams) that see through the grating version converge after the grating version, produce in confluence area and interfere.Interference figure has the three-dimensional periodic structure, and this structure is relevant with three grating diffration angles (being central light beam and other three angle of beams).Place the holographic recording dry plate 5 (as the photoetching hectograph) of photoresists thicker (more than several microns) in producing the zone of three-dimensional structure pattern, exposure is developed then to dry plate, promptly is made into three-D photon crystal.Exposure is identical with the method for developing with making hologram usually.

The grating version can adopt photochemigraphy material or hologram recording material, and preferably the grating version must have transparency preferably, to allow more light pass through.Grating on the grating version can be made of the method for photochemigraphy, also can make of hologram recording method.When making of holographic method, material therefor is the holographic recording dry plate, record be transmission-type grating.Because crystalline network is relevant with the grating diffration angle, and the grating diffration angle is relevant with the fringe spacing of grating,, make that the first-order diffraction angle of grating is desired angle so when making grating, must select suitable fringe spacing.Area to three gratings 41 and central space zone 42 is not strict with, but preferably the area of the first-order diffraction light of grating is approaching with the area of the light that sees through from the center white space, can make full use of light source like this, make four bundle interference of light zones reach maximum, help making the large-area three-dimensional photonic crystal.

Claims

1, method for manufacturing three-dimensional photonic crystal, it is characterized in that laser through expanding bundle and spatial filtering, become the directional light that expands bundle again, the directional light that expands after restrainting is shone on the grating version, after the grating version, produce the 4 bundle interference of light, place the holographic recording dry plate at interference region, behind exposure imaging, promptly get three-D photon crystal.

2, three-D photon crystal preparation facilities, it is characterized in that being provided with laser instrument, be provided with 1 successively and expand bundle and spatial filter, 1 collimation lens, 1 grating version and 1 holographic recording dry plate on the light path of laser instrument output laser, said grating version forms the 4 bundle interference of light to the directional light that expands after restrainting.

3, three-D photon crystal preparation facilities as claimed in claim 2 is characterized in that laser is to holographic recording dry plate sensitivity.

4, three-D photon crystal preparation facilities as claimed in claim 2 is characterized in that said grating version is provided with three gratings, and a white space is arranged at the center of grating version, and three gratings differ 120 ° round the central area between each grating.

5,, it is characterized in that said grating version is photochemigraphy material or hologram recording material as claim 2 or 4 described three-D photon crystal preparation facilities.

6, as claim 2 or 4 described three-D photon crystal preparation facilities, it is characterized in that said original screen panel white space be shaped as square, circle, triangle or other shape.