阅读说明：本技术 一种用于太赫兹真空电子器件的宽带输能窗 (Broadband energy transmission window for terahertz vacuum electronic device ) 是由 苏思铭 张长青 潘攀 蔡军 冯进军 于 2021-08-09 设计创作，主要内容包括：本发明公开一种用于太赫兹真空电子器件的宽带输能窗,包括：由两端向内依次同中心轴设置的矩形波导、渐变段、圆波导和介质窗片；所述介质窗片与两侧的圆波导密封焊接；所述宽带输能窗关于介质窗片对称；其中,所述渐变段由矩形波导内腔和形成在矩形波导宽边中线外侧的金属槽组成；所述金属槽关于矩形波导宽边中线和中心轴所在的平面对称；所述金属槽的宽边长度小于折叠波导的宽边长,金属槽与中心轴的垂直距离小于圆波导的半径。该宽带输能窗具有较小的反射特性,能够满足宽频带需要,同时波导的结构参数敏感性低,对加工精度和装配精度要求小,加工成品率高,易于规模化生产。(The invention discloses a broadband energy transmission window for a terahertz vacuum electronic device, which comprises: the rectangular waveguide, the gradual change section, the circular waveguide and the dielectric window sheet are arranged from two ends inwards and sequentially share the central shaft; the dielectric window sheet is hermetically welded with the circular waveguides on the two sides; the broadband energy transmission window is symmetrical about the medium window sheet; the gradual change section consists of a rectangular waveguide inner cavity and a metal groove formed on the outer side of the central line of the wide side of the rectangular waveguide; the metal groove is symmetrical about a plane where a central line and a central axis of the wide side of the rectangular waveguide are located; the length of the wide side of the metal groove is smaller than that of the wide side of the folded waveguide, and the vertical distance between the metal groove and the central shaft is smaller than the radius of the circular waveguide. The broadband energy transmission window has a small reflection characteristic, can meet the requirement of a broadband, is low in structural parameter sensitivity of the waveguide, has low requirements on machining precision and assembly precision, is high in machining yield, and is easy for large-scale production.)

1. A broadband energy delivery window for terahertz vacuum electronic devices, comprising:

the rectangular waveguide, the gradual change section, the circular waveguide and the dielectric window sheet are arranged from two ends inwards and sequentially share the central shaft;

the dielectric window sheet is hermetically welded with the circular waveguides on the two sides;

the broadband energy transmission window is symmetrical about the medium window sheet;

the gradual change section consists of a rectangular waveguide inner cavity and a metal groove formed on the outer side of the central line of the wide side of the rectangular waveguide;

the metal groove is symmetrical about a plane where a central line and a central axis of the wide side of the rectangular waveguide are located;

the length of the wide side of the metal groove is smaller than that of the wide side of the folded waveguide, and the vertical distance between the metal groove and the central shaft is smaller than the radius of the circular waveguide.

2. The broadband energy delivery window for terahertz vacuum electronic devices as claimed in claim 1, wherein the shape of the metal groove is selected from square, rectangular or arc.

3. The broadband energy delivery window for terahertz vacuum electronic devices as claimed in claim 1, wherein the number of transition sections on one side of the dielectric window is one or more.

4. The broadband energy delivery window for terahertz vacuum electronic devices as claimed in claim 1, wherein when the number of the transition sections on one side of the dielectric window is plural, the shapes of the metal grooves in the plural transition sections are the same or different.

5. The broadband energy delivery window for terahertz vacuum electronic devices as claimed in claim 1, wherein the dielectric window piece is made of a material selected from CVD diamond, sapphire, beryllium oxide or aluminum nitride.

6. A terahertz vacuum electronic device, characterized by comprising the broadband energy transmission window for the terahertz vacuum electronic device as claimed in any one of claims 1 to 5.

Technical Field

The present invention relates to the field of vacuum electronic devices. And more particularly, to a broadband power transmission window for terahertz vacuum electronic devices.

Background

The vacuum electronic device has important application value in the fields of communication, imaging, detection and the like, and the main obstacle restricting the development of the vacuum electronic device is that the output power level is lower. The microwave energy transmission window is an important component of the vacuum electronic device. The energy transmission window can ensure that the vacuum electronic device works under a vacuum condition, and also ensures small reflection and low input and output loss. In the terahertz frequency band, the loss of electromagnetic waves passing through the window is large, the structural size is very small, and the requirements on the strength, the thermal property and the dielectric constant of materials of the window frame and the window are more strict.

Most of the energy transmission windows used at present are box-shaped windows. The box-shaped window has the advantages of simple structure, mature process, wide cold measurement bandwidth and the like, and the electric field on the surface of the window sheet is weak, so that the box-shaped window can bear high peak power and is easy to cool structurally. The device is widely used in the fields of vacuum electronic devices, magnetrons, gyrotrons, klystrons, accelerators and the like. The basic structure of the conventional box window is shown in fig. 1A and 1B. The two ends of the window are connected with the standard rectangular waveguide, and the center of the middle circular waveguide is hermetically welded with the medium window sheet.

Although the electrical parameters such as bandwidth, loss and the like of the traditional box-shaped window can meet the actual requirements, the welding is difficult, the structural strength is weak and the vacuum airtightness reliability is low due to the adoption of the side wall sealing process. Especially in the terahertz frequency band, the structure size is very small, and the sealing is more difficult. In practice, therefore, a standard box window is generally used, and its basic structure is shown in fig. 2A and 2B. The dielectric window sheet of the standard box-shaped window has a larger diameter than the circular waveguide, and the edge of the window sheet is sealed with the circular waveguide, so that the structural strength and the air tightness reliability are greatly improved.

At present, the bandwidth of the standard box-shaped window with reflection less than-20 dB can reach 49.5GHz, and the requirement of 190-240GHz frequency band is met, but the sensitivity of the diameter and the length of the circular waveguide is too high, the processing error of +/-0.01 mm can cause the great deterioration of the window performance, the yield is low, and the standard box-shaped window is not suitable for batch production.

Therefore, it is desirable to provide an energy delivery window that is easy to manufacture and meets the frequency band requirements.

Disclosure of Invention

The invention aims to provide a broadband energy transmission window for a terahertz vacuum electronic device, which has the advantages of low structural parameter sensitivity of a waveguide, low requirements on processing precision and assembly precision, high processing yield and easiness in large-scale production under the conditions of meeting the frequency band requirement and excellent reflection characteristic.

Another object of the present invention is to provide a terahertz vacuum electronic device including the above broadband energy transmission window.

In order to achieve the purpose, the invention adopts the following technical scheme:

a broadband energy delivery window for terahertz vacuum electronic devices, comprising:

the rectangular waveguide, the gradual change section, the circular waveguide and the dielectric window sheet are arranged from two ends inwards and sequentially share the central shaft;

the dielectric window sheet is hermetically welded with the circular waveguides on the two sides;

the broadband energy transmission window is symmetrical about the medium window sheet;

the gradual change section consists of a rectangular waveguide inner cavity and a metal groove formed on the outer side of the central line of the wide side of the rectangular waveguide;

the metal groove is symmetrical about a plane where a central line and a central axis of the wide side of the rectangular waveguide are located;

the length of the wide side of the metal groove is smaller than that of the wide side of the folded waveguide, and the vertical distance between the metal groove and the central shaft is smaller than the radius of the circular waveguide.

Preferably, the shape of the metal groove is selected from square, rectangular or arc.

Preferably, the number of transitions on one side of the media pane is one or more.

Preferably, when the number of transitions on one side of the dielectric pane is plural, the shapes of the metal troughs in the plural transitions are the same or different.

Preferably, the dielectric louver material is selected from CVD diamond, sapphire, beryllium oxide or aluminum nitride.

A terahertz vacuum electronic device comprising the broadband energy transmission window.

The invention has the following beneficial effects:

the invention provides a broadband energy transmission window for a terahertz vacuum electronic device, which is compared with a standard box-shaped window in the prior art, wherein a gradual change section is arranged between a rectangular waveguide and a circular waveguide, the broadband energy transmission window has smaller reflection characteristic and can meet the frequency band requirement, meanwhile, the structural parameter sensitivity of the waveguide is low, the requirements on processing precision and assembly precision are low, the processing yield is high, and the large-scale production is easy.

Drawings

The following describes embodiments of the present invention in further detail with reference to the accompanying drawings.

Fig. 1A and 1B illustrate a structural schematic view of a conventional box window.

Fig. 2A and 2B illustrate a structural schematic view of a standard box window.

Fig. 3 shows a schematic 45-degree side view of a broadband power transmission window structure according to the present invention.

Fig. 4 is a schematic front view of a broadband power transmission window structure according to the present invention.

Detailed Description

In order to more clearly illustrate the invention, the invention is further described below with reference to preferred embodiments and the accompanying drawings. Similar parts in the figures are denoted by the same reference numerals. It is to be understood by persons skilled in the art that the following detailed description is illustrative and not restrictive, and is not to be taken as limiting the scope of the invention.

The invention provides a gradient section broadband energy transmission window for a terahertz vacuum electronic device, which is compared with a standard box-shaped window in the prior art as shown in FIGS. 2A and 2B, a gradient section is arranged between a rectangular waveguide and a circular waveguide, and therefore, the structure of the broadband energy transmission window is shown in FIGS. 3 and 4. Specifically, the broadband energy transmission window of the present invention includes: the rectangular waveguide 1, the gradual change section 2, the circular waveguide 3 and the dielectric window 4 are arranged from two ends inwards and are sequentially concentric with a central shaft 5; the dielectric window sheet 4 is hermetically welded with the circular waveguides 3 on the two sides, so that the vacuum property of the energy transmission window is guaranteed; the broadband energy transmission window is symmetrical about the dielectric window 4, namely, the waveguides on two sides of the dielectric window 4 are symmetrically distributed; whereinThe gradual change section 2 consists of a rectangular waveguide 1 and a metal groove 21 formed outside a central line 6 of the wide side of the rectangular waveguide; the metal slot 21 is symmetrical about the plane where the center line 6 and the center line 5 of the rectangular waveguide broadside are located, and the broadside length a of the metal slot 21₁Is less than the width side length a of the rectangular waveguide 1₂Perpendicular distance R of metal groove 21 from central axis 5₂Smaller than the radius R of the circular waveguide 3₁。

In a specific implementation, the shape of the metal groove in the small transition section includes, but is not limited to, a square, a rectangle, an arc, etc., and the metal groove in fig. 3 and 4 is an arc. When the metal groove is arc-shaped, the vertical distance between the metal groove and the central axis refers to the radius of the arc of the cross section of the arc-shaped metal groove.

It will be understood by those skilled in the art that the number of transition sections on one side of the dielectric window in the energy transmission window may be one or more for different frequency bands, different powers, different sizes of folded waveguide vacuum electronic devices; when the number of the transition sections is multiple, the shapes of the metal grooves in the multiple transition sections can be the same or different; and the adjustment of the size of each structural parameter of the broadband energy transmission window are all within the protection scope of the invention.

In specific examples, the dielectric louver material includes, but is not limited to, CVD diamond, sapphire, beryllium oxide, aluminum nitride, or the like.

In the specific implementation process, the smaller the reflection coefficient at two ports of the energy transmission window and the rectangular waveguide are connected, the better the matching is, and the wider the frequency band is, the better the matching is. For example, when the target reflection characteristics S11, S22 < -20dB and the bandwidth is more than 40GHz, the broadband energy transmission window structure provided by the invention has the advantage that the processing error is +/-0.02 mm, and the target reflection characteristics and the bandwidth can be ensured.

The technical scheme of the invention is further illustrated by combining specific comparative examples and examples.

Comparative example

The standard box-shaped window in comparative example 1 is shown in fig. 2A and 2B, the dielectric window of the standard box-shaped window is a CVD diamond window, the center frequency is 200 to 260GHz, the rectangular waveguide is a standard waveguide of a 220GHz band, the radius R of the circular waveguide is 0.85 to 0.95mm, the length h of the circular waveguide is 0.25 to 0.35mm, and by analyzing a waveguide parameter sensitivity curve, it can be known that the tolerance of the radius R of the circular waveguide is ± 0.005mm, the tolerance of the length h is ± 0.01mm, the sensitivity of the structural parameter is extremely high, and the realization is extremely difficult in the process.

Examples

The structure of the broadband energy transmission window with the gradual change section is shown in figures 3 and 4, a dielectric window sheet of the broadband energy transmission window is a CVD diamond window sheet, one side of the window sheet is provided with the gradual change section, and a metal groove is arched. For a broadband energy transmission window with the center frequency of 200-260 GHz, the rectangular waveguide is a standard waveguide of a 220GHz frequency band, and the radius R of the circular waveguide₁0.85-0.95 mm in length h₁0.25-0.35 mm; height R of the metal bath₂0.25-0.35 mm in length h₂0.45-0.55 mm. The height R of the metal groove can be known by analyzing the waveguide parameter sensitivity curve₂The tolerance is-0.04 mm- +0.06mm, the length h₂The tolerance of (2) is +/-0.1 mm; radius R of circular waveguide₁And length h₁The tolerance of (3) is +/-0.02 mm. Therefore, the broadband energy transmission window has low structural parameter sensitivity, has low requirements on processing precision and assembly precision, and is easy to realize in process. Meanwhile, the reflection characteristic S of the broadband energy transmission window₁₁<-30dB, which can meet the requirements.

Compared with the prior art, the broadband energy transmission window provided by the invention has the advantages that on the basis of meeting the requirements of reflection characteristics and frequency bandwidth, the sensitivity of the waveguide structure parameters is lower, the process is easier to realize, the batch processing can be realized, and the broadband energy transmission window has wider application prospect.

It should be understood that the above-mentioned embodiments of the present invention are only examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention, and it will be obvious to those skilled in the art that other variations or modifications may be made on the basis of the above description, and all embodiments may not be exhaustive, and all obvious variations or modifications may be included within the scope of the present invention.