JP2004012850A - Three-dimensional periodic structure, method for manufacturing the same, high-frequency element, and high-frequency system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To constitute a three-dimensional periodic structure which is applicable to a function element of a small size even in a frequency band lower than an optical frequency, such as, for example, a microwave band, and a method for manufacturing the same, a high-frequency element, and a high-frequency system. <P>SOLUTION: The three-dimensional periodic structure 101 comprises a three-dimensional periodic structural section 100 in which two substances varying in dielectric constants are distributed with periodicity in three-dimensional axial directions and an object 3 of prescribed dimensions, such as a dielectric substance, which is embedded into the structural section 100 and is different from the two substances constituting the three-dimensional periodic structural section. Such structure is arranged within, for example, a waveguide 4. A transmission line or the like having a filter function is constituted by such a structure. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a three-dimensional periodic structure that can be used as a part of an electronic component, a method for manufacturing the same, a high-frequency element, and a high-frequency device.
[0002]
[Prior art]
In a solid crystal, a periodic potential distribution constituted by nuclei exhibits an interference effect on an electron wave having a wavelength corresponding to a lattice constant. That is, when the wavelength of the electron wave is very close to the potential period of the crystal, reflection occurs due to three-dimensional diffraction (Bragg diffraction). Due to this phenomenon, electrons contained in a specific energy region are prohibited from passing therethrough. This is the formation of an electronic band gap used for semiconductor devices and the like.
[0003]
Similarly, a three-dimensional structure in which the refractive index or the dielectric constant changes periodically exhibits an interference effect on electromagnetic waves, and blocks electromagnetic waves in a specific frequency region. In this case, the forbidden band is called a photonic band gap, and the three-dimensional structure is called a photonic crystal.
[0004]
Utilizing such an action of the photonic crystal, for example, it is used as a cutoff filter that blocks transmission of electromagnetic waves in a predetermined frequency band, or introduces a non-uniform portion that disturbs the period into the periodic structure, and It has been considered to be used as a waveguide or a resonator in which light or an electromagnetic wave is confined in a portion. Further, application to an ultra-low threshold laser of light, a highly directional antenna of electromagnetic waves, and the like is also considered.
[0005]
Generally, when Bragg diffraction of an electromagnetic wave occurs in a photonic crystal, two types of standing waves are formed. FIG. 18 shows the two types of standing waves. The standing wave A has high energy in the region where the vibration of the wave has a low dielectric constant, and the standing wave B has high energy in the region where the vibration of the wave has a high dielectric constant. A wave having energy between the standing waves split into the two different modes cannot exist in the crystal, thus creating a band gap. If it is desired to widen the band gap, the energy difference between the two standing waves may be widened. For that purpose, it is effective to increase the contrast of the dielectric constant between the two media or to increase the volume ratio of the medium having a high dielectric constant.
[0006]
This photonic crystal has a one-dimensional, two-dimensional, or three-dimensional structure, but a three-dimensional structure is necessary to obtain a complete photonic band gap.
[0007]
As a method for obtaining a three-dimensional structure, (1) Japanese Patent Application Laid-Open No. H10-335758, "A three-dimensional periodic structure, a method for manufacturing the same, and a method for manufacturing a film"; And (3) Japanese Patent Application Laid-Open No. 2000-258645 "3D periodic structure and 2D periodic structure and methods for producing them".
[0008]
[Problems to be solved by the invention]
These three-dimensional periodic structures have been invented with a view to being applied to various devices utilizing the photo band gap, but specific examples of functional elements such as filters in the microwave band are used. No application is shown.
[0009]
Further, these three-dimensional periodic structures are suitable for optical frequencies, but if they are applied to the microwave band as they are, their size will be increased as a whole.
[0010]
An object of the present invention is to provide a three-dimensional periodic structure that can be applied to a functional element in a frequency band lower than an optical frequency, such as a microwave band, a manufacturing method thereof, a high-frequency element, and a high-frequency device. .
[0011]
[Means for Solving the Problems]
In the three-dimensional periodic structure of the present invention, two substances having different dielectric constants are periodically distributed in a three-dimensional axial direction, and occupy a three-dimensional space having a predetermined external dimension. It is characterized in that an object of a predetermined size made of a substance different from the two substances is embedded.
[0012]
Further, in the three-dimensional periodic structure according to the present invention, one of the two substances is an air hole having a diamond crystal lattice structure, and a plurality of air holes among the plurality of air holes are formed of a material different from the two substances. It is characterized in that an object is arranged.
[0013]
Further, the three-dimensional periodic structure of the present invention is arranged such that two substances having different dielectric constants are distributed with periodicity in a three-dimensional axial direction and occupy a three-dimensional space having a predetermined outer dimension. A space of a predetermined size filled with one of the two substances is provided.
[0014]
Further, the three-dimensional periodic structure of the present invention is characterized in that the period is changed along an axis in a predetermined direction among the three-dimensional axes.
[0015]
The transmission line according to the present invention is characterized in that any one of the three-dimensional periodic structures is arranged in a waveguide.
[0016]
Further, a transmission line according to the present invention is characterized in that the three-dimensional periodic structure described in any one of the above is arranged on one or both surfaces of a substrate which is a part of the transmission line.
[0017]
Further, a transmission line according to the present invention is characterized in that a transmission line made of a conductive film is formed on the substrate.
[0018]
Further, the transmission line of the present invention is characterized in that the substrate has a multilayer structure including circuit elements such as capacitors, inductors, and interlayer connection conductors inside.
[0019]
In the filter of the present invention, the transmission path is provided in a part of the signal transmission path, and the transmission characteristic of the high-frequency element is used.
[0020]
An isolator according to the present invention includes the transmission path in a part of a signal transmission path.
[0021]
In the coupler of the present invention, the transmission path is provided in a part of a signal transmission path.
[0022]
An antenna according to the present invention includes the transmission path in a part of a signal transmission path.
[0023]
A high-frequency device according to the present invention includes any one of the filter, the isolator, the coupler, and the antenna.
[0024]
The method of manufacturing a three-dimensional periodic structure according to the present invention is a method of manufacturing a three-dimensional periodic structure, wherein the light irradiation of a cross-sectional pattern to be formed is repeated for each layer with respect to a photocurable resin. A structure is formed by the distribution of one of the substances, and an object having a predetermined size made of a substance different from the two substances is arranged during the stereolithography.
[0025]
BEST MODE FOR CARRYING OUT THE INVENTION
A three-dimensional periodic structure, a method for manufacturing the same, and a configuration of a transmission line according to the first embodiment will be described with reference to FIGS. 1, 2, and 15 to 17.
FIG. 1 is a cutaway perspective view of a transmission line. FIG. 2 is a sectional view thereof. Here, reference numeral 4 denotes a waveguide, and a three-dimensional periodic structure 101 is arranged in a space inside the waveguide. In FIG. 2, reference numeral 1 denotes a dielectric which is one substance of the three-dimensional periodic structure 100, and 2 denotes an air hole which is the other substance. The three-dimensional periodic structure of the dielectric 1 and the air holes 2 constitutes a three-dimensional periodic structure part 100. The portion indicated by 3 is a dielectric having a rectangular cross section extending along the signal transmission direction of the waveguide 4. The three-dimensional periodic structure 100 and the dielectric 3 constitute a three-dimensional periodic structure 101.
[0026]
The three-dimensional periodic structure 100 functions as a photonic crystal. In order for the photonic crystal to exhibit a sufficient electromagnetic wave reflection function, it is necessary to form a wide band gap in all crystal directions. The ideal crystal structure is a three-dimensional diamond structure. The diamond structure has eight lattice points in the unit cell, four of which form independent face-centered cubic lattices, one of which is parallel to the other along a solid diagonal by 1/4 of its length. Occupies the position moved to.
[0027]
A photonic crystal having a diamond structure is a crystal in which a spherical dielectric is arranged at a lattice point of the diamond structure, or a crystal that simulates atomic bonds of the diamond structure by a combination of dielectric columns.
[0028]
The three-dimensional periodic structure portion 100 shown in FIG. 1 is one in which air holes having a diamond-type lattice structure are periodically distributed in a resin. Such a structure can be called an inverted diamond structure. Here, the lattice portion is cylindrical, the ratio of the diameter to the length of the cylindrical portion is 2: 3 (aspect ratio 1.5), and the lattice constant is 10 mm.
[0029]
FIG. 15 shows an apparatus for manufacturing the three-dimensional periodic structure 101 shown in FIG. Here, reference numeral 15 denotes a container that fills an epoxy photocurable resin 18 that is cured by ultraviolet rays. Reference numeral 16 denotes an elevator table that moves up and down inside the container 15, and 19 denotes an object formed on an upper portion of the elevator table 16. Reference numeral 17 denotes a squeegee for applying the photocurable resin 18 to the upper surface of the object 19 by a predetermined thickness.
[0030]
Reference numeral 10 denotes a laser diode, 11 denotes a harmonic generation element (LBO) for converting the wavelength of the laser light from the laser diode 10 to generate ultraviolet light, 12 denotes an acousto-optic element (AOM) as a wavelength selection element, and 13 denotes The scanning mirror 14 is an fθ lens. These constitute an optical system.
[0031]
The procedure for manufacturing a photonic crystal using such an optical shaping apparatus is as follows.
First, the elevator table 16 is lowered from the liquid surface of the photo-curable resin 18 to a predetermined depth, and the squeegee 17 is moved in a direction along the liquid surface. A resin film is formed. In this state, the liquid surface is irradiated with an ultraviolet laser having a wavelength of 355 nm as a beam having a spot diameter of 50 μm at an output of 110 mW by the above optical system. At this time, by modulating the laser diode 10 while controlling the scanning mirror 13, the laser beam is irradiated to a position where the photo-curable resin 18 is to be cured, and control is performed so as not to irradiate other regions.
[0032]
On the liquid surface of the photocurable resin 18 irradiated with the laser beam, a spherical cured phase having a diameter of 120 μm is formed by the polymerization reaction. At this time, when the laser beam is scanned at a speed of 90 m / s, a cured phase having a thickness of 150 μm is formed.
Thus, the object 19 corresponding to the first-layer cross-sectional pattern is formed by raster-scanning the laser beam.
[0033]
Next, the elevator table 16 is lowered by about 200 μm, and the squeegee 17 is moved to form a photocurable resin film having a thickness of about 200 μm on the surface of the object 19.
[0034]
After that, by scanning and modulating the laser beam in the same manner as in the first layer, a sectional pattern of the second layer is formed on the first layer. At this time, the upper and lower layers are joined by polymerization curing. The third and subsequent layers are the same as the second layer. The object 19 is formed by repeating this process.
[0035]
FIG. 16 is a perspective view showing the shape of the object at each stage when a large number of layers are formed. However, here, for ease of illustration, a pattern of a portion which is not cured without being irradiated with a laser beam, that is, an air hole portion is shown. (A) shows a state where only one unit is formed in the crystal axis <111> direction of the diamond structure. (B) shows a state in which this is molded into about 4 units. (C) shows a state where the above process is repeated for a predetermined unit to form a model.
[0036]
In the apparatus shown in FIG. 15, a CAD / CAM process is used to cure the photocurable resin 18 in a predetermined sectional pattern with respect to the liquid surface of the photocurable resin 18. That is, the pattern as shown in FIG. 16 is designed in advance by CAD that handles three-dimensional data, and the data of the three-dimensional structure is temporarily converted into STL (Stereolithography) data, and this is converted into two-dimensional data at a predetermined position by slice software. Convert to a set of two-dimensional section data. Finally, data for modulating the laser diode when raster-scanning the laser beam is created from the two-dimensional cross-sectional data. Based on the data thus prepared, the laser diode is scanned and the laser diode is modulated.
[0037]
FIG. 17 shows a procedure for manufacturing the three-dimensional periodic structure 101 using the above-described optical shaping apparatus. First, as shown in (A), the three-dimensional periodic structure part 100 is optically formed to a predetermined height, and thereafter, as shown in (B), the three-dimensional periodic structure part 100 is optically formed so that a groove d is formed. Thereafter, as shown in (C), the dielectric 3 preformed is inserted into the groove d. Subsequently, the three-dimensional periodic structure 100 is formed also on the upper part of the dielectric 3, and the three-dimensional periodic structure 101 in which the dielectric 3 is embedded in the three-dimensional periodic structure 100 is formed as shown in FIG. obtain.
[0038]
By disposing the three-dimensional periodic structure 101 manufactured as described above in the waveguide 4, the transmission path has a transmission characteristic in which a predetermined frequency due to the photonic band gap of the three-dimensional periodic structure 100 is greatly attenuated. Will be shown.
[0039]
On the other hand, the electromagnetic field of the predetermined transmission mode concentrates on the dielectric 3 existing at the center of the waveguide 4, and the entire transmission line acts as a dielectric line.
[0040]
The pass band of the dielectric line is matched with the signal frequency band to be transmitted, and at the same time, the attenuation band by the three-dimensional periodic structure unit 100 is matched with the frequency band to be cut off. Thus, it can be used as a transmission line having a filter function of transmitting only a signal component of a frequency band to be transmitted.
[0041]
Next, a configuration of a transmission line according to the second embodiment will be described with reference to FIG.
FIG. 3 is a sectional view of the transmission line. Here, 1 is a dielectric, 2 is an air hole, and the dielectric 1 and the air hole 2 form a three-dimensional periodic structure. Reference numeral 3 'denotes a dielectric (dielectric piece) buried in a predetermined portion of the plurality of portions to be the air holes 2. The three-dimensional periodic structure 101 including the dielectric 1, the air hole 2, and the dielectric 3 'is arranged inside the waveguide 4.
[0042]
This three-dimensional periodic structure 101 uses a stereolithography apparatus similar to that shown in FIG. 15 to stereolithographically form the dielectric 1 and the air hole 2 portion, and fits inside the air hole 2 into the air hole. It is manufactured by repeating the step of dropping the dielectric 3 ′ of the size to be dropped.
[0043]
As described above, since the dielectrics 3 'made of a material different from the dielectric 1 are distributed in the lattice of the three-dimensional periodic structure, the three-dimensional periodic structure 101 has Pass / cut characteristics of different frequency bands can be provided.
[0044]
Note that a conductor film may be formed in advance on the surface of the dielectric 3 '. In addition, an object made of a conductive material such as a metal may be distributed instead of the dielectric material. As a result, the transmission characteristic of the transmission path can be determined by the distribution.
[0045]
Next, a transmission path according to the third embodiment will be described with reference to FIGS.
FIG. 4 is a sectional view of the transmission line. Here, reference numeral 5 denotes a substrate on which the three-dimensional periodic structure 100 is arranged. The dielectric constant of the substrate 5 is higher than the dielectric constant of either of the two substances constituting the three-dimensional periodic structure 100. A three-dimensional periodic structure including the substrate 5 and the three-dimensional periodic structure 100 is provided in the waveguide 4.
[0046]
In FIG. 4, the three-dimensional periodic structure unit 100 has the same structure as the three-dimensional periodic structure unit 100 shown in the first and second embodiments. The substrate 5 is a dielectric ceramic substrate or a resin substrate. The three-dimensional periodic structure unit 100 may be arranged independently above and below the substrate 5 or may be configured such that the substrate 5 is embedded in one continuous three-dimensional periodic structure unit.
[0047]
FIG. 5 shows transmission characteristics of the transmission line when the substrate 5 is provided and when it is not provided. By arranging the substrate 5 having an effective dielectric constant higher than the three-dimensional periodic structure portion 100, the cutoff frequency band is shifted to a lower frequency side as a whole, and the attenuation is increased. This is due to the fact that the cutoff frequency of the transmission line has shifted to a lower frequency due to the dielectric constant of the substrate, or a change in the cutoff condition due to the shape and size of the substrate.
[0048]
Next, a configuration of a transmission line according to a fourth embodiment will be described with reference to FIG.
(A) and (B) are cross-sectional views of the transmission line. Basically, three-dimensional periodic structures 100a and 100b are arranged above and below a substrate 5 in the same manner as shown in FIG. 4, and a three-dimensional periodic structure composed of the substrate 5 and the three-dimensional periodic structures 100a and 100b. The body is located inside the waveguide 4.
[0049]
In the example shown in FIG. 6A, a gap 7 extending in the signal transmission direction is provided in one of the three-dimensional periodic structures 100a. In the example shown in (B), the three-dimensional periodic structures 100a and 100b have different three-dimensional periods in the predetermined axial direction. In this manner, different frequency band cutoff characteristics can be provided for each location in the waveguide, and the electrical characteristics of the entire waveguide can be reduced as compared with the case where a uniform three-dimensional periodic structure is provided. Can be variously determined.
[0050]
Note that the structure of the three-dimensional periodic structure unit 100 may be a periodic tilt structure in which the period changes sequentially along a predetermined axis.
[0051]
Next, a configuration of a transmission line according to a fifth embodiment will be described with reference to FIGS.
FIG. 7 is a partial perspective view of a transmission line cut along a plane perpendicular to the signal transmission direction and having a predetermined length in the signal transmission direction. In FIG. 7, reference numeral 5 denotes a substrate constituting a main part of the transmission line. The three-dimensional periodic structure 101 is arranged above and below the main part of the substrate 5. That is, the substrate 5 is sandwiched between the three-dimensional periodic structures 101.
[0052]
FIG. 8 is a perspective view in a state where upper and lower three-dimensional periodic structures 101 are removed from the state shown in FIG. On the upper and lower surfaces of the substrate 5, electrodes 6 extending in the signal transmission direction are formed. The substrate 5 and the electrodes 6 formed on its surface constitute various transmission lines such as a strip line, a slot line, and a coplanar line. Further, a suspended line may be formed by providing a shield around the substrate 5.
[0053]
FIG. 9 is an exploded perspective view of a substrate having another structure. In the example shown in FIG. 8, the transmission line is formed by forming the electrode 6 on a single-layer (single-plate) dielectric substrate. However, in the example shown in FIG. 9, the transmission line is composed of five layers indicated by 5a to 5e. This is a multilayer substrate. 5a has a coil pattern, 5b has a capacitor pattern, 5c has a shield pattern, and 5d has a trimming pattern. In addition, a conductor for interlayer connection is formed in a cross section or inside of the substrate by using what is called LTCC technology. As described above, a multi-layer substrate provided with circuit elements such as capacitors, inductors, and interlayer connection conductors inside may be used. Thereby, a plurality of electrical performances of the substrate and a cutoff characteristic of the three-dimensional periodic structure 101 can be simultaneously exhibited.
[0054]
Next, a configuration of a filter according to a sixth embodiment will be described with reference to FIG. (A) is a perspective view and (B) is a longitudinal sectional view thereof. Here, reference numeral 21 denotes a rectangular cylindrical cavity whose two openings are covered by panels 22a and 22b. The panels 22a and 22b are provided with coaxial connectors 23a and 23b and coupling loops 24a and 24b connected to their center conductors, respectively. A three-dimensional periodic structure 101 is disposed inside the cavity 21. The three-dimensional periodic structure 101 is any one of the three-dimensional periodic structures described in the first to fifth embodiments. Basically, the inside of the cavity 21 acts as a cavity resonator, but the presence of the three-dimensional periodic structure 101 attenuates the frequency corresponding to the photo band gap. By matching the resonance frequency of the spurious mode to its attenuation frequency, this filter acts as a band-pass filter that passes the fundamental frequency band of the cavity resonator and attenuates a predetermined frequency band out of the attenuation band more. .
[0055]
Next, a configuration of an isolator according to a seventh embodiment will be described with reference to FIG.
FIG. 11 is a cross-sectional view in a plane perpendicular to the signal transmission direction. In this isolator, a ferrite plate 25 is inserted into a rectangular waveguide 4 at an asymmetric position with respect to a tube axis, and a three-dimensional periodic structure 100 is arranged in a space around the ferrite 25. A DC magnetic field Hdc is externally applied to the ferrite plate 25. In the TE10 mode rectangular waveguide, there are oscillating magnetic fields Hx and Hz having phases different from each other by 90 °, and at any one point, the combined rotating magnetic field has an elliptical knitted wave in the yz plane. The direction of rotation of this polarization is opposite on both sides of the yz plane including the tube axis. The waves traveling in the positive z direction and the waves traveling in the negative z direction are also opposite to each other. Therefore, by appropriately selecting the DC magnetic field Hdc, a wave propagating in the positive direction of the z-axis generates a positive rotating magnetic field and is attenuated by resonance absorption, and a wave traveling in the negative direction is not attenuated. This acts as an isolator. At this time, since the unnecessary frequency band propagating in the waveguide 4 is attenuated by the presence of the three-dimensional periodic structure 100, this isolator can be used as an isolator having a filter function.
[0056]
The right and left three-dimensional periodic structure portions 100 of the ferrite 25 may be formed separately, but the ferrite 25 is embedded in the three-dimensional periodic structure portion 100 to integrate them, and the whole is three-dimensionally structured. It may be configured as a periodic structure.
[0057]
Next, a configuration of a coupler according to an eighth embodiment will be described with reference to FIG.
In this coupler, two transmission lines are arranged, and a coupling element for coupling the waves in both transmission lines is provided on the tube wall. In this example, holes ha and hb are provided as coupling elements at a distance of 1/4 wavelength of the guide wavelength. With this structure, a signal transmitted in the direction from port # 1 to port # 2 is added and output in the same phase toward port # 4, but is canceled and not output because it is added in the opposite phase toward port # 3.
[0058]
These two transmission lines have any of the structures shown in the first to fifth embodiments. Therefore, this coupler functions as a coupler having a filter function of transmitting only a frequency band to be transmitted and cutting off an unnecessary frequency band.
[0059]
Next, the configuration of the antenna according to the ninth embodiment will be described with reference to FIG.
FIG. 13 is a partial perspective view of the slot antenna. Here, reference numeral 4 denotes a waveguide, in which the three-dimensional periodic structure 101 shown in the first to fifth embodiments is arranged. A plurality of slots s are provided on one side of the waveguide 4. These slots s are excited in phase to obtain maximum radiation transverse to the waveguide 4. The unnecessary frequency band of the signal transmitted through the waveguide 4 is attenuated by the presence of the three-dimensional periodic structure 101, so that antenna characteristics with less spurious can be obtained.
[0060]
Next, the configuration of a radar according to a tenth embodiment will be described with reference to FIG.
In FIG. 14, 31 is an oscillator, 32 is an amplifier for amplifying the oscillation signal, 33 is an isolator for blocking a return signal to the amplifier 32, and 34 is a coupler for extracting a part of the transmission signal as a local signal. 36 is an antenna, and 37 is a mixer. A circulator 35 outputs a transmission signal to the antenna 36 and outputs a reception signal from the antenna 36 to the mixer 37 side. Mixer 37 mixes the received signal and the local signal to generate a beat signal. The filter 38 extracts a necessary frequency component from the beat signal and outputs it as a reception intermediate frequency signal IF.
[0061]
An isolator having the structure shown in FIG. 11 is used as the isolator 33, a coupler having a structure shown in FIG. 12 is used as the coupler 34, and an antenna having a structure shown in FIG. The transmission path shown in FIG. 1 to FIG. 9 is used for each transmission path.
[0062]
In this manner, by using a high-frequency element having a filter function, a radar having a small size, high sensitivity, and low spurious characteristics is configured.
[0063]
【The invention's effect】
According to the present invention, two substances having different dielectric constants are periodically distributed in a three-dimensional axial direction, and occupy a three-dimensional space having a predetermined external dimension. Embedded in an object of a predetermined size made of different materials, compared with a three-dimensional periodic structure in which two materials having different dielectric constants are distributed periodically in a three-dimensional axial direction, have a lower optical frequency, for example, a microscopic structure. Even when applied to a waveband, a three-dimensional periodic structure that can be applied to a functional element in a frequency band lower than the optical frequency without increasing the size as a whole is obtained.
[0064]
According to the invention, one of the two substances is an air hole having a diamond crystal lattice structure, and an object of a substance different from the two substances is arranged in a plurality of air holes among these air holes. This facilitates the positioning of the object.
[0065]
According to the present invention, two substances having different dielectric constants are periodically distributed in a three-dimensional axial direction, and occupy a three-dimensional space having a predetermined outer dimension. By providing a space of a predetermined size to be filled with one of the substances, compared to a three-dimensional periodic structure in which two substances having different dielectric constants are periodically distributed in a three-dimensional axial direction, the optical frequency is higher. Even when applied to a lower band, for example, a microwave band, a three-dimensional periodic structure that can be applied to a functional element in a frequency band lower than the optical frequency without increasing the overall size can be obtained.
[0066]
Further, according to the present invention, by changing the period along the axis in the predetermined direction among the three-dimensional axes, the number of design parameters is increased as compared with the case where the period is constant, and more functionality is achieved. A high three-dimensional periodic structure is obtained.
[0067]
According to the present invention, by arranging any one of the three-dimensional periodic structures in the waveguide, for example, a transmission line having a filter function for a signal in a microwave band can be configured.
[0068]
Further, according to the present invention, by arranging the three-dimensional periodic structure according to any one of the above on one or both surfaces of a substrate which is a part of a transmission line, for example, for a signal in a microwave band. Thus, a transmission line having a filter function can be configured.
[0069]
Further, according to the present invention, since the transmission line is formed by the conductive film on the substrate, the characteristics as a transmission line formed by the conductive film and the substrate and the electrical characteristics by the three-dimensional periodic structure are combined. A transmission path having characteristics can be obtained.
[0070]
Further, according to the present invention, the substrate has a multilayer structure including circuit elements such as capacitors, inductors, and interlayer connection conductors therein, thereby providing a multifunctional device having electric characteristics of a circuit formed on the substrate. A transmission path is obtained.
[0071]
According to the present invention, since the transmission path is provided in a part of the signal transmission path, a filter having transmission characteristics of the transmission path can be obtained.
[0072]
According to the present invention, since the transmission path is provided in a part of the signal transmission path, an isolator having a filter characteristic can be obtained.
[0073]
According to the present invention, by providing the transmission path in a part of the signal transmission path, a coupler having a filter characteristic can be obtained.
[0074]
According to the present invention, since the transmission path is provided in a part of the signal transmission path, an antenna having filter characteristics can be obtained.
[0075]
According to the present invention, a high-functional high-frequency device including any one of the filter, the isolator, the coupler, and the antenna can be obtained.
[0076]
According to the present invention, the structure based on the distribution of one of the two substances of the three-dimensional periodic structure is obtained by a stereolithography method in which light irradiation of a cross-sectional pattern to be formed is repeated for each layer on the photocurable resin. Since a body is formed and an object having a predetermined size made of a substance different from the two substances is arranged in the course of the stereolithography, a three-dimensional periodic structure can be easily manufactured.
[Brief description of the drawings]
FIG. 1 is a partial perspective view of a transmission line according to a first embodiment.
FIG. 2 is a sectional view of the transmission line.
FIG. 3 is a cross-sectional view of a transmission line according to a second embodiment.
FIG. 4 is a sectional view of a transmission line according to a third embodiment.
FIG. 5 is a diagram showing transmission characteristics of the transmission line.
FIG. 6 is a sectional view of a transmission line according to a fourth embodiment.
FIG. 7 is a partial perspective view of a transmission line according to a fifth embodiment.
FIG. 8 is a partial perspective view of a substrate used for the transmission line.
FIG. 9 is an exploded perspective view showing the configuration of another substrate.
FIG. 10 is a perspective view and a cross-sectional view of a filter according to a sixth embodiment.
FIG. 11 is a sectional view of an isolator according to a seventh embodiment.
FIG. 12 is a schematic sectional view of a coupler according to an eighth embodiment.
FIG. 13 is a partial perspective view of an antenna according to a ninth embodiment.
FIG. 14 is a block diagram illustrating a configuration of a radar according to a tenth embodiment.
FIG. 15 is a diagram showing a configuration of an optical shaping apparatus.
FIG. 16 is a view showing a state in which the object is being formed by the optical forming apparatus;
FIG. 17 is a diagram showing a manufacturing process of a three-dimensional periodic structure by a stereolithography method.
FIG. 18 is a diagram showing two standing waves when substances having different dielectric constants are distributed with periodicity.
[Explanation of symbols]
1- Dielectric
2- air hole
3,3'-dielectric
4-waveguide
5-substrate
6-electrode
7-void
10-Laser diode
11-harmonic generation element (LBO)
12-Acoustic-optic element (AOM)
13-scanning mirror
14-fθ lens
15-container
16-elevator table
17-Squeegee
18-Photocurable resin
19-Object
21-cavity
22-panel
23-coaxial connector
24--joining loop
25-ferrite
100-3D periodic structure
101-3D periodic structure
d-groove

Claims (14)

A three-dimensional periodic structure in which two substances having different dielectric constants are periodically distributed in a three-dimensional axial direction and occupy a three-dimensional space having a predetermined outer dimension;
A three-dimensional periodic structure, wherein an object having a predetermined size made of a substance different from the two substances is embedded in the three-dimensional space. One of the two substances is an air hole having a diamond crystal lattice structure, and an object made of a substance different from the two substances is arranged in a plurality of air holes among the air holes. Item 3. The three-dimensional periodic structure according to item 1. A three-dimensional periodic structure in which two substances having different dielectric constants are periodically distributed in a three-dimensional axial direction and occupy a three-dimensional space having a predetermined outer dimension;
3. A three-dimensional periodic structure, wherein a space of a predetermined size filled with one of the two substances is provided in the three-dimensional space. 4. The three-dimensional periodic structure according to claim 1, wherein the three-dimensional periodic structure changes a period along an axis in a predetermined direction among the three-dimensional axes. 5. A transmission line comprising the three-dimensional periodic structure according to claim 1 arranged in a waveguide. A transmission line in which the three-dimensional periodic structure according to claim 1 is arranged on one or both surfaces of a substrate that is a part of the transmission line. 7. The transmission line according to claim 6, wherein a transmission line made of a conductive film is formed on the substrate. The transmission line according to claim 7, wherein the substrate has a multilayer structure including a circuit element such as a capacitor, an inductor, and an interlayer connector inside. A filter that partially includes the transmission path element according to claim 5 and that uses transmission characteristics of the transmission path. An isolator partially provided with the transmission line according to claim 5. A coupler partially provided with the transmission line according to claim 5. An antenna partially provided with the transmission path according to claim 5. A high-frequency device comprising: the filter according to claim 9, the isolator according to claim 10, the coupler according to claim 11, or the antenna according to claim 12. 3. The three-dimensional periodic structure according to claim 1, wherein the light irradiation of a cross-sectional pattern to be formed is repeated for each layer on the photocurable resin by a stereolithography method. A three-dimensional periodic structure for manufacturing the three-dimensional periodic structure according to claim 1 or 2 by forming a structure and arranging the object according to claim 1 or 2 during the stereolithography. Manufacturing method.

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