CN102522680A - Method for designing Brewster window - Google Patents
Method for designing Brewster window Download PDFInfo
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- CN102522680A CN102522680A CN2011104368131A CN201110436813A CN102522680A CN 102522680 A CN102522680 A CN 102522680A CN 2011104368131 A CN2011104368131 A CN 2011104368131A CN 201110436813 A CN201110436813 A CN 201110436813A CN 102522680 A CN102522680 A CN 102522680A
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Abstract
The invention discloses a method for designing a Brewster window. During preparation of substrate crystal of the Brewster window, the substrate crystal axis growing direction is accordant to the laser transmission direction, and the crystal cut surface normal direction and the crystal axis growing direction form a corresponding Brewster angle. By the method for designing the Brewster window, the problems of absorption and loss aggravation during laser transmission can be improved effectively while laser polarization is guaranteed, the service life of the Brewster window is prolonged, and stable long-effective operation of a whole system can be guaranteed.
Description
Technical field
The present invention relates to gas laser technology, relate to the method for designing of the Brewster window in a kind of gas laser particularly.
Background technology
Gas laser is the relevant work medium to extraordinary the application with the characteristic gas, produces population inversion through effective high-pressure discharge (or laser pumping) excitation gas, forms the laser emission output of corresponding optical maser wavelength.Especially in some particular application, the output of the laser of additional polarization characteristic has more important use and is worth.
As the simplest polarizing component; The effect that the Brewster window of cavity both sides plays air seal and produces laser polarization in the gas laser; Because inside, air seal chamber relates to the electrion process; Thereby cause the anisopleual temperature and pressure environmental impact of window, the Brewster window is plated film not usually, and is one of optical element of most important and easy damaged in the gas laser.Its design fundamentals are the Brewster effects that taken place when transmitting at different transmission mediums interface through random polarisation.
As shown in Figure 1, for catadioptric situation signal takes place at the different refractivity medium interface in light.Light is by n among Fig. 1
1Medium is to n
2Medium transmission, angle of incidence of light are θ
1, reflection ray is equally with θ
1The angle reflection gets into n
2Deviation takes place behind the medium interface, and the refraction angle is θ
2, light is followed Fresnel law, i.e. n in the situation of medium interface generation deflection of light
1Sin θ
1=n
2Sin θ
2Satisfying θ
1+ θ
2Under=90 ° the situation, so-called Brewster effect takes place, form the refracted ray output with certain polarization characteristic, the corresponding incidence angle of Brewster's angle when producing the Brewster effect (also for passing the angle of emergence that has behind the certain thickness optical material).
The effect of Brewster window is the sealing of in gas laser, serving as gaseous discharge cavity, produces the laser output with certain polarization characteristic according to the Brewster effect simultaneously.Because discharging chamber relates to the electrion process; Temperature, pressure change violent; So have bigger temperature, pressure gap in Brewster window both sides, the Brewster window is plated film not usually, and easily because many-sided reasons such as optics material, level of processing, absorption loss and Stress Release cause the window damage; Even it is broken; So how to solve the damage problem of Brewster window preferably, improve element useful life, be the prerequisite and the basis of realizing the gas laser good operation.
Brewster window normal and transmission ray direction angle are determined by the Fresnel law of interface light transmission.By Fresnel law: n
1Sin θ
1=n
2Sin θ
2(n
1, n
2Be media of both sides refractive index in interface under the laser wavelength of incidence effect, θ
1Be incidence angle, θ
2Be the refraction angle), Brewster effect θ
1+ θ
2=90 °, thereby by Fresnel law θ
1=arctg (n
2/ n
1).
In some gas laser technical application, Brewster window and be the CaF of cubic system with laserresonator chamber mirror substrate material
2Material,<111>The crystallographic axis direction of growth is its conventional crystal direction of growth, and the crystal-cut direction is usually along vertical<111>The plane of axle, minimum along the optical transmission loss of the crystallographic axis direction of growth, concrete condition is shown in Fig. 2 a.Because the restriction of Brewster window polarizing angle degree, the window normal direction becomes corresponding Brewster angle with the laser transmission direction usually, and the resonant cavity eyeglass is generally 0 ° of incident, thus use and the application of resonant cavity eyeglass compared to the Brewster window, because at CaF
2The difference of transmission direction in the crystal, for laser at CaF
2Transmission in the material and degree of impairment exist very big different.Concrete gas laser structure situation is shown in Fig. 2 b.
For the sake of simplicity and increase comparativity, with CaF
2The Brewster window of substrate material and uncoated resonant cavity output eyeglass are the example explanation.Shown in Fig. 2 c, Fig. 2 d, traditional Brewster window sheet crystallographic axis direction of growth is vertical each other with the crystal-cut direction, and promptly the optical normal line direction of window becomes corresponding Brewster angle (to the specific laser wavelength transmission) simultaneously with the laser transmission direction; And uncoated resonant cavity output eyeglass (0 ° of incident) the crystallographic axis direction of growth is vertical each other with the window cut direction; But be parallel to each other with the laser transmission direction; So to backing material of the same race; Because the difference of the crystallographic axis direction of growth that difference caused of practical application and laser transmission direction must cause the absorption that laser caused in the transmission course and the difference of damage effect in crystal (window or eyeglass); Thereby will quicken the wearing and tearing of Brewster window to a certain extent, reduce optical element useful life, and then influence the stability of light quality and system works.
Summary of the invention
The object of the present invention is to provide a kind of method for designing of Brewster window,, improve optical element useful life, the stability of enhanced system work with absorption and the degree of impairment that improves laser transmission in the Brewster window.
For realizing above-mentioned purpose; The method for designing of Brewster window provided by the invention; Be that substrate crystal at the Brewster window prepares in the process; Make the substrate crystallographic axis direction of growth and laser transmission direction consistent, substrate crystal cut surface normal direction becomes corresponding Brewster angle with the substrate crystallographic axis direction of growth.
Shown in Fig. 2 b; The laser transmission direction is a horizontal direction; The resonant cavity window plays sealing gas and plays a part inclined to one side; According to real-world operation optical maser wavelength, resonant window sheet crystal refractive index (under the real-world operation optical maser wavelength condition), according to the Fresnel law of interface light transmission and cloth like that special efficacy should (as previously mentioned) confirm the special like that angle of cloth of window normal direction and laser transmission direction jointly, thereby the angle design of realization Bu Shi window.
Brewster window design method provided by the invention has improved effectively in the past that laser transmission absorbs the problem of aggravating with loss, has improved this special window of scholar useful life, for the long stable effect of total system provides safeguard.
Description of drawings
Fig. 1 is light interface transmission Fresnel law sketch map.
Fig. 2 a is the crystal structure sketch map of cubic system.
Fig. 2 b is the gas laser structural representation.
Fig. 2 c is traditional Brewster window sketch map.
Fig. 2 d is plated film resonant cavity outgoing mirror sketch map not.
The Brewster window sketch map that Fig. 3 designs for the present invention.
Embodiment
To the design and the application mode of traditional Brewster window optical element, the invention provides the method for designing of Brewster window.Method for designing of the present invention is as shown in Figure 3; Make the crystallographic axis direction of growth and laser transmission direction consistent; And crystal-cut face normal direction becomes corresponding Brewster angle with the crystallographic axis direction of growth; The absorption and the degree of impairment of laser transmission in the Brewster window be will improve so to a certain extent, optical element useful life, the stability of enhanced system work improved.
The present invention is through the crystallographic axis direction of growth, crystal-cut direction and the laser transmission direction three relation each other of adjustment Brewster window backing material; Change the deviation of Brewster angle between the laser transmission direction and the crystallographic axis direction of growth in the past; Make laser along the minimum crystallographic axis direction of growth transmission of absorption loss; Farthest reduce transmission absorption and the damage problem of laser in crystalline material, the useful life of improving optical element, the overall operation usefulness of enhancing gas laser.
For more advancing explanation technical scheme of the present invention, below lift CaF commonly used in the current gas laser technology
2The Brewster window of material be designed to example.Other substrate crystal materials designs that are used to make the Brewster window also can be used for reference similar method.
As shown in Figure 1, for catadioptric situation signal takes place at the different refractivity medium interface in light.Light is by n among Fig. 1
1Medium is to n
2Medium transmission, angle of incidence of light are θ
1, reflection ray is equally with θ
1The angle reflection gets into n
2Deviation takes place behind the medium interface, and the refraction angle is θ
2, light is followed Fresnel law, i.e. n in the situation of medium interface generation deflection of light
1Sin θ
1=n
2Sin θ
2Satisfying θ
1+ θ
2Under=90 ° the situation, so-called Brewster effect takes place, form the refracted ray output with certain polarization characteristic, the corresponding incidence angle of Brewster's angle when producing the Brewster effect (also for passing the angle of emergence that has behind the certain thickness optical material).
The effect of Brewster window is the sealing of in gas laser, serving as gaseous discharge cavity, produces the laser output with certain polarization characteristic according to the Brewster effect simultaneously.Because discharging chamber relates to the electrion process; Temperature, pressure change violent; So have bigger temperature, pressure gap in Brewster window both sides, the Brewster window is plated film not usually, and easily because many-sided reasons such as optics material, level of processing, absorption loss and Stress Release cause the window damage; Even it is broken; So how to solve the damage problem of Brewster window preferably, improve element useful life, be the prerequisite and the basis of realizing the gas laser good operation.
Below through CaF commonly used in the gas laser technology
2The material optical element is an example explanation relevant design situation.Shown in Fig. 2 a, CaF
2Material is a cubic crystal structure, and crystallographic axis direction of growth multiselect is selected as<111>Axle, promptly along cubic crystal body diagonal direction,, minimum along crystallographic axis direction of growth loss in the direction that the identical point of corresponding three-dimensional coordinate datum level projection is constituted; The crystal-cut direction usually adopt with<111>Cut direction also can be selected according to actual needs in the plane that axle is perpendicular.
Fig. 2 b is the gas laser structural representation, and gas laser mainly is made up of gas discharge chamber 1, Brewster window 2, high reflection mirror 3, outgoing mirror 4.The Brewster window is put according to real-world operation wavelength and medium refraction index situation characteristic, guarantees that laser outbound course and Brewster window normal direction form Brewster's angle, thereby forms the refracted ray output with certain polarization characteristic; High reflection mirror is parallel with the laser transmission direction with the outgoing mirror normal; I.e. 0 ° of angle; The two constitutes laserresonator, swashs to the formed energy of the counter-rotating transition of the gas medium under electrion (or laser pumping) condition to inject capable resonance amplification, finally produces laser output.
Fig. 2 c is depicted as the correlation of laser transmission direction, the crystallographic axis direction of growth and the crystal-cut direction of Brewster window in the gas laser.By just finding out that the crystallographic axis direction of growth and the window normal of Brewster window are parallel to each other, and be vertical each other with the crystal-cut direction among the figure, become Brewster's angle with the laser transmission direction simultaneously; Fig. 2 d is depicted as the correlation of laser transmission direction, the crystallographic axis direction of growth and the crystal-cut direction of outgoing mirror in the gas laser (can select plated film outgoing mirror not-unified mutually with the Brewster window).By can just finding out that the crystallographic axis direction of growth and the outgoing mirror normal of outgoing mirror are parallel to each other, and be vertical each other with the crystal-cut direction among the figure, also be parallel to each other with the laser transmission direction simultaneously.Obviously under these circumstances; Compare the Brewster window with outgoing mirror and will produce bigger laser transmission loss; Consider the special environment for use (influences such as temperature, pressure) of Brewster window simultaneously; This will produce influence greatly for the Brewster window useful life, and then reduce the running usefulness of overall gas Optical Maser System.
The method for designing of Brewster window of the present invention is as shown in Figure 3; The crystallographic axis direction of growth and the laser transmission direction of Brewster window are parallel to each other; The crystal-cut direction is vertical each other with Brewster window normal, will ensure to a certain extent that like this laser through the low-loss transmission in the Brewster window process, reduces damage; Increase the service life, improve the task performance of system.
Claims (2)
1. the method for designing of a Brewster window; Be that substrate crystal at the Brewster window prepares in the process; Make the substrate crystallographic axis direction of growth and laser transmission direction consistent, substrate crystal cut surface normal direction becomes corresponding Brewster angle with the substrate crystallographic axis direction of growth.
2. method for designing according to claim 1, wherein, said substrate crystal is a calcium fluoride crystal.
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| CN201110436813.1A CN102522680B (en) | 2011-12-23 | 2011-12-23 | A kind of method for designing of Brewster window |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105846302A (en) * | 2016-06-02 | 2016-08-10 | 中国科学院物理研究所 | Novel Kerr-lens mode-locking Cr: ZnS femtosecond laser |
| CN106154396A (en) * | 2016-07-05 | 2016-11-23 | 北京大学 | A kind of ultra broadband Terahertz Brewster vacuum window and preparation method thereof |
| CN106392816A (en) * | 2016-11-03 | 2017-02-15 | 福建福晶科技股份有限公司 | Machining method of Brewster window sheet |
| CN111308583A (en) * | 2020-04-02 | 2020-06-19 | 湖州中芯半导体科技有限公司 | CVD diamond Brewster window structure and preparation method thereof |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5670519A (en) * | 1979-11-15 | 1981-06-12 | Kokusai Denshin Denwa Co Ltd <Kdd> | Light isolator |
| CN101276126A (en) * | 2008-04-23 | 2008-10-01 | 清华大学 | Double Brewster's angle nonlinear optical crystal and cutting method thereof |
| CN101539703A (en) * | 2009-01-22 | 2009-09-23 | 福州高意通讯有限公司 | Frequency multiplier |
| CN101719626A (en) * | 2009-11-06 | 2010-06-02 | 华中科技大学 | Electric-optically Q-switched laser resonator |
| JP2010278289A (en) * | 2009-05-29 | 2010-12-09 | Toshiba Corp | Laser oscillation apparatus |
-
2011
- 2011-12-23 CN CN201110436813.1A patent/CN102522680B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5670519A (en) * | 1979-11-15 | 1981-06-12 | Kokusai Denshin Denwa Co Ltd <Kdd> | Light isolator |
| CN101276126A (en) * | 2008-04-23 | 2008-10-01 | 清华大学 | Double Brewster's angle nonlinear optical crystal and cutting method thereof |
| CN101539703A (en) * | 2009-01-22 | 2009-09-23 | 福州高意通讯有限公司 | Frequency multiplier |
| JP2010278289A (en) * | 2009-05-29 | 2010-12-09 | Toshiba Corp | Laser oscillation apparatus |
| CN101719626A (en) * | 2009-11-06 | 2010-06-02 | 华中科技大学 | Electric-optically Q-switched laser resonator |
Non-Patent Citations (1)
| Title |
|---|
| 郑玮等: "20MHz自启动克尔透镜锁模飞秒钛宝石激光器", 《中国激光》, vol. 29, no. 6, 30 June 2002 (2002-06-30), pages 481 - 484 * |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105846302A (en) * | 2016-06-02 | 2016-08-10 | 中国科学院物理研究所 | Novel Kerr-lens mode-locking Cr: ZnS femtosecond laser |
| CN106154396A (en) * | 2016-07-05 | 2016-11-23 | 北京大学 | A kind of ultra broadband Terahertz Brewster vacuum window and preparation method thereof |
| CN106154396B (en) * | 2016-07-05 | 2019-05-14 | 北京大学 | A kind of ultra wide band Terahertz Brewster vacuum window and preparation method thereof |
| CN106392816A (en) * | 2016-11-03 | 2017-02-15 | 福建福晶科技股份有限公司 | Machining method of Brewster window sheet |
| CN111308583A (en) * | 2020-04-02 | 2020-06-19 | 湖州中芯半导体科技有限公司 | CVD diamond Brewster window structure and preparation method thereof |
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| CN102522680B (en) | 2015-08-12 |
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Inventor after: Zhao Jiangshan Inventor after: Li Hui Inventor after: Sha Pengfei Inventor after: Bao Yang Inventor after: Song Xingliang Inventor after: Zhou Yi Inventor after: Wang Yu Inventor before: Zhao Jiangshan Inventor before: Li Hui Inventor before: Sha Pengfei Inventor before: Song Xingliang Inventor before: Zhou Yi Inventor before: Wang Yu |
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Free format text: CORRECT: INVENTOR; FROM: ZHAO JIANGSHAN LI HUI SHA PENGFEI SONG XINGLIANG ZHOU YI WANG YU TO: ZHAO JIANGSHAN LI HUI SHA PENGFEI BAO YANG SONG XINGLIANG ZHOU YI WANG YU |
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Effective date of registration: 20160909 Address after: 100176, Yizhuang economic and Technological Development Zone, Beijing, Daxing District Hai Industrial Park, No. 10 building Patentee after: Beijing science and Technology Co., Ltd. Address before: 100094 Haidian District, Deng Zhuang Road, No. 9, Beijing Patentee before: Inst of Photoelectrics, C.A.S |