CN103457009A

CN103457009A - Terahertz low-loss bent waveguide

Info

Publication number: CN103457009A
Application number: CN2013103609089A
Authority: CN
Inventors: 陈麟; 朱亦鸣; 高春梅; 徐嘉明
Original assignee: University of Shanghai for Science and Technology
Current assignee: University of Shanghai for Science and Technology
Priority date: 2013-08-16
Filing date: 2013-08-16
Publication date: 2013-12-18
Anticipated expiration: 2033-08-16
Also published as: CN103457009B

Abstract

The invention relates to a terahertz low-loss bent waveguide which comprises an outer waveguide plate and an inner waveguide plate. The outer waveguide plate and the inner waveguide plate are bent metal plates and bent portions of the plates are arc. The outer waveguide plate is parallel to the inner waveguide plate with a distance in between. Periodical grooves are formed in opposite surfaces of the outer waveguide plate and the inner waveguide plate. Terahertz waves are input from one end of the outer waveguide plate and one end of the inner waveguide plate in a horizontal magnetic wave mode and enter a gap between the outer waveguide plate and the inner waveguide plate so that surface waves can be transmitted in the gap, and are further transmitted to the other end of the outer waveguide plate and the outer end of the inner waveguide plate. Thus, low-loss bent transmission of the terahertz waves is achieved. According to the technical scheme, the bent loss of the terahertz waves is low and the terahertz low-loss bent waveguide is simple in structure, convenient to use and low in cost.

Description

Terahertz low-loss curved waveguide

Technical field

The present invention relates to a kind of Terahertz low-loss curved waveguide.

Background technology

Terahertz (THz) ripple is the electromagnetic wave between microwave and far infrared.In recent years, along with the development of ultrafast laser technique, make the generation of terahertz pulse that stable, reliable excitation source arranged, make people can study Terahertz.Terahertz has a wide range of applications in fields such as biomedicine, safety monitoring, nondestructive detecting, astronomy, spectrum and imaging technique and information sciences.Terahertz waveguide is a kind of basic transmission apparatus of Terahertz application and is the Primary Component of Terahertz communication system.In the world, the people such as Maier have studied propagation characteristic (the Nature Photonics of THz wave in the structuring metal surface in 2008,2,175-179,2008), Nahata equals to have studied in 2011 pseudo-surface plasma waveguide (the Optics Express on the rectangular recess array, 19,1072-1080,2011), but the transverse electric size of all these structures is larger, cause in the situation that crooked loss is larger.

Summary of the invention

The object of the invention is to overcome above-mentioned existing waveguide in the situation that the larger defect of crooked loss.

In order to realize this purpose, the invention provides a kind of Terahertz low-loss curved waveguide, it comprises outside waveguide plate and inboard waveguide plate, outside waveguide plate and inboard waveguide plate is crooked metallic plate and bend is circular-arc, outside waveguide plate and inboard waveguide plate are arranged in parallel each other apart, are respectively equipped with outside periodically groove on the surfaces opposite to each other of side wave guide plate and inboard waveguide plate.

Preferably, the metal material of outside waveguide plate and inboard waveguide plate is a kind of in aluminium, copper, silver, iron, nickel.

According to a preferred embodiment of the invention, the angle of bend of waveguide is right angle, and bending radius is greater than 500 μ m.

According to a preferred embodiment of the invention, wherein outside waveguide plate and inboard waveguide plate shape are similar, and size and the gap periods of the groove on the groove on the waveguide plate of the outside and inboard waveguide plate are all identical.

According to a preferred embodiment of the invention, the groove on the groove on the waveguide plate of the outside and inboard waveguide plate is about the center line symmetry between outside waveguide plate and inboard waveguide plate.

According to a preferred embodiment of the invention, the width of groove is 50～500 μ m, and the degree of depth is 50～500 μ m, and length is for being not less than 500 μ m; The width of its further groove is preferably 152 μ m, and the degree of depth is preferably 274 μ m.

According to a preferred embodiment of the invention, the periodic intervals of groove is preferably 475 μ m.

According to a preferred embodiment of the invention, the arc radius on two surfaces of bend of outside waveguide plate is respectively 0.8mm and 1.2mm, and the arc radius on two surfaces of bend of inboard waveguide plate is respectively 0.2mm and 0.6mm.

According to a preferred embodiment of the invention, the spacing between outside waveguide plate and inboard waveguide plate is 0.1～0.5mm, and reaching medium in groove between plate is air.

Compared with prior art, according to technical scheme of the present invention, not only reduced the THz wave bending loss, and simple in structure, easy to use, with low cost.

The accompanying drawing explanation

Fig. 1 shows the structure of Terahertz low-loss curved waveguide according to one preferred embodiment of the present invention with stereogram signal property;

Fig. 2 has further schematically shown the structure of Terahertz low-loss curved waveguide according to one preferred embodiment of the present invention with end view.

Embodiment

Describe Terahertz low-loss curved waveguide of the present invention in detail below in conjunction with accompanying drawing.It will be appreciated by those skilled in the art that the embodiment the following describes is only to exemplary illustration of the present invention, but not for it being made to any restriction.

As shown in Figure 1, in according to a preferred embodiment of the invention, Terahertz low-loss curved waveguide comprises two metallic plates i.e. outside waveguide plate 1 and inboard waveguide plate 2, these two metallic plates are all crooked metallic plates, bend (corner) is circular-arc, between outside waveguide plate 1 and the parallel placement of inboard waveguide plate 2 and outside waveguide plate 1 and inboard waveguide plate 2, certain gap is arranged, the relative surface of side wave guide plate 1 and inboard waveguide plate 2 is provided with periodically groove outside, namely the inner surface of side wave guide plate 1 is provided with periodicity groove 11 and is provided with periodically groove 21 on the outer surface of inboard waveguide plate 2 outside.In addition, be understandable that, the transmission length that the quantity of groove can be required according to reality determines, the transmission length here refers to the transmission length of terahertz signal in practical application, the length of namely waveguide.

Wherein, the shape of outside waveguide plate 1 and inboard waveguide plate 2 can be similar, and the groove 11 on outside waveguide plate 1 and the size of the groove 21 on inboard waveguide plate 2 and gap periods can be all identical.Preferably, groove 11 and groove 21 are the symmetry status distribution about the center line between outside waveguide plate 1 and inboard waveguide plate 2.

THz wave is the end input from outside waveguide plate 1 and inboard waveguide plate 2 with the transverse magnetic wave pattern, after entering the gap between outside waveguide plate 1 and inboard waveguide plate 2, the formation surface wave transmits in this gap, and then be sent to the other end of outside waveguide plate 1 and inboard waveguide plate 2, thereby realize the low bend loss transmission of THz wave.

The angle of bend that it is pointed out that crooked metallic plate (namely outside waveguide plate 1 and inboard waveguide plate 2) can be for arbitrarily angled, for example 90 °.

The bending radius of waveguide is preferably greater than 500 μ m, and here, the center line outside the bending radius of waveguide refers between waveguide plate 1 and inboard waveguide plate 2 is in the bending radius of sweep.

This Terahertz curved waveguide can change to low-loss the transmission direction of THz wave.In addition, it will be appreciated by persons skilled in the art that and can realize by the distance between plates between adjustment groove size and outside waveguide plate 1 and inboard waveguide plate 2 transmission of the THz wave of different-waveband.

Below, further describe the structure of Terahertz low-loss curved waveguide according to one preferred embodiment of the present invention with reference to Fig. 2.As shown in Figure 2, distance B between outside waveguide plate 1 and inboard waveguide plate 2 is 200 μ m, groove 11, 21 depth H are 274 μ m, groove 11, 21 width W are 152 μ m, groove 11, 21 cycle T that occur are 475 μ m, the long L1 of plate is 3mm, the long L2 of plate is 3mm, thickness of slab S is 0.4mm, plate is wide is 2mm, arc radius R1 is 0.2mm, arc radius R2 is 0.6mm, arc radius R3 is 0.8mm, arc radius R4 is 1.2mm, the bending radius of this waveguide is 700 μ m, the length of groove is identical with the waveguide plate width, outside waveguide plate 1 and inboard waveguide plate 2 angle of bend are 90 °, reaching medium in groove between plate is air.

Exemplary main procedure of processing (following step 1-2) and the loss test (following step 3-4) of Terahertz low-loss curved waveguide according to one preferred embodiment of the present invention then, are described in the lump.

1) first with size out two of the metallic plates (outside waveguide plate 1 and inboard waveguide plate 2) of certain thickness and 90 ° of bendings of the method for machining, then process groove 11,21 by mechanical micro-machined method on the respective surfaces of metallic plate, as shown in Figure 2.

2) by outside waveguide plate 1 and the relatively parallel placement of the reeded face of inboard waveguide plate 2, and further make groove 11,21 corresponding, guarantee two plate opposing parallel simultaneously.

3) open time domain THz wave spectra system (TDS system), the above-mentioned Terahertz low-loss curved waveguide as shown in Figure 2 of making is linked into to position suitable in the TDS system, makes the slit incident of terahertz signal from Terahertz low-loss curved waveguide one end.

4) image data: the photoconductive receiver of use TDS system is gathered the output signal of Terahertz low-loss curved waveguide.

Test result show this Terahertz low-loss curved waveguide output signal at 0.4THz to the signal transmissivity of 0.6THz higher than 95%, this obviously is better than the loss of curved waveguide of the prior art.

Terahertz low-loss curved waveguide of the present invention is simple in structure, easy to use, with low cost.

Claims

1. a Terahertz low-loss curved waveguide, it is characterized in that: comprise outside waveguide plate and inboard waveguide plate, described outside waveguide plate and described inboard waveguide plate are crooked metallic plate and bend is circular-arc, described outside waveguide plate and described inboard waveguide plate are arranged in parallel each other apart, are respectively equipped with periodically groove on the surfaces opposite to each other of described outside waveguide plate and described inboard waveguide plate.

2. Terahertz low-loss curved waveguide according to claim 1, the metal material of wherein said outside waveguide plate and described inboard waveguide plate is a kind of in aluminium, copper, silver, iron, nickel.

3. Terahertz low-loss curved waveguide according to claim 1, the angle of bend of wherein said waveguide is right angle, bending radius is greater than 500 μ m.

4. Terahertz low-loss curved waveguide according to claim 1, wherein said outside waveguide plate and described inboard waveguide plate shape are similar, and size and the gap periods of the groove on the groove on the waveguide plate of the described outside and described inboard waveguide plate are all identical.

5. Terahertz low-loss curved waveguide according to claim 1, the groove on the groove on the waveguide plate of the wherein said outside and described inboard waveguide plate is about the center line symmetry between described outside waveguide plate and described inboard waveguide plate.

6. Terahertz low-loss curved waveguide according to claim 1, the width of wherein said groove is 50～500 μ m, and the degree of depth is 50～500 μ m, and length is for being not less than 500 μ m.

7. Terahertz low-loss curved waveguide according to claim 6, the width of wherein said groove is 152 μ m, the degree of depth is 274 μ m.

8. Terahertz low-loss curved waveguide according to claim 1, the periodic intervals of wherein said groove is 475 μ m.

9. Terahertz low-loss curved waveguide according to claim 1, the arc radius on two surfaces of bend of wherein said outside waveguide plate is respectively 0.8mm and 1.2mm, and the arc radius on two surfaces of bend of described inboard waveguide plate is respectively 0.2mm and 0.6mm.

10. according to the described Terahertz low-loss of any one curved waveguide in claim 1-9, the spacing between wherein said outside waveguide plate and described inboard waveguide plate is 0.1～0.5mm, and reaching medium in described groove between plate is air.