CN112414566A - Terahertz wavelength double-path measuring device based on Michelson interference - Google Patents
Terahertz wavelength double-path measuring device based on Michelson interference Download PDFInfo
- Publication number
- CN112414566A CN112414566A CN202011228186.8A CN202011228186A CN112414566A CN 112414566 A CN112414566 A CN 112414566A CN 202011228186 A CN202011228186 A CN 202011228186A CN 112414566 A CN112414566 A CN 112414566A
- Authority
- CN
- China
- Prior art keywords
- terahertz
- light
- laser
- reflector
- wavelength
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000006073 displacement reaction Methods 0.000 claims description 7
- 238000012545 processing Methods 0.000 claims description 3
- 230000008859 change Effects 0.000 abstract description 10
- 238000000034 method Methods 0.000 abstract description 9
- 230000003287 optical effect Effects 0.000 abstract description 6
- 230000008569 process Effects 0.000 abstract description 2
- 238000005259 measurement Methods 0.000 description 11
- 230000005540 biological transmission Effects 0.000 description 3
- 238000001514 detection method Methods 0.000 description 3
- 238000011161 development Methods 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 2
- 238000000691 measurement method Methods 0.000 description 2
- 238000004891 communication Methods 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 230000007123 defense Effects 0.000 description 1
- 238000003384 imaging method Methods 0.000 description 1
- 230000001737 promoting effect Effects 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 230000001052 transient effect Effects 0.000 description 1
- 230000000007 visual effect Effects 0.000 description 1
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01J—MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
- G01J9/00—Measuring optical phase difference; Determining degree of coherence; Measuring optical wavelength
- G01J9/02—Measuring optical phase difference; Determining degree of coherence; Measuring optical wavelength by interferometric methods
- G01J9/0246—Measuring optical wavelength
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01J—MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
- G01J9/00—Measuring optical phase difference; Determining degree of coherence; Measuring optical wavelength
- G01J9/02—Measuring optical phase difference; Determining degree of coherence; Measuring optical wavelength by interferometric methods
- G01J2009/028—Types
- G01J2009/0284—Michelson
Landscapes
- Physics & Mathematics (AREA)
- Spectroscopy & Molecular Physics (AREA)
- General Physics & Mathematics (AREA)
- Investigating Or Analysing Materials By Optical Means (AREA)
Abstract
The invention relates to the technical field of optical metering, and provides a terahertz wavelength double-path measuring device based on Michelson interference. The terahertz light path module can measure the change number of interference fringes generated by terahertz light, the laser light path module can measure the change number of the interference fringes generated by laser, the movable platform can move the reflector in one dimension, and the computer can control the movable platform to move and process signals received by the detector to calculate terahertz wavelength. According to the invention, the measuring device has a simple structure, the method is convenient and fast, the reliability of the measuring result is high, and the terahertz wavelength can be traced conveniently.
Description
Technical Field
The invention relates to the technical field of optical metering, relates to detection and calibration of terahertz wavelength, and particularly relates to a terahertz wavelength double-path measuring device based on Michelson interference.
Background
Terahertz refers to electromagnetic waves with the frequency of 0.1-10THz and the wavelength of 0.03-3mm, and is just between microwave millimeter waves and infrared optics with relatively good scientific and technical development. Terahertz has the characteristics of transient property, broadband property, coherence, low energy and the like, and is often applied to important fields of substance component identification, high-speed communication, biomedicine, security imaging, military and national defense and the like as a new technical means.
Wavelength is one of important basic parameters of electromagnetic waves, but due to the lack of materials and devices suitable for terahertz frequency bands, the development of measurement methods and techniques is lagged compared with those of long-wave microwave bands and short-wave infrared bands, and therefore methods and tools for satisfying the measurement of terahertz band wavelength need to be explored. The method for researching the accurate terahertz wavelength measurement has very important significance for promoting the development of terahertz technology and expanding the application range of terahertz.
Terahertz wavelength measuring instruments can be classified into several types, such as fabry-perot interference type, fizeau interference type, michelson interference type, heterodyne mixing type, grating splitting type and the like according to the measuring principle. The michelson interference type is widely used for terahertz wavelength measurement due to the simple principle and compact structure and can be applied to free space.
Disclosure of Invention
The invention aims to provide a terahertz wavelength two-way measuring device based on Michelson interference, and aims to solve the problems in the background technology.
The technical scheme of the invention is as follows: the utility model provides a terahertz wavelength double-circuit measuring device based on michelson is interfered which is characterized in that, includes terahertz light path module, laser light path module, moving platform and computer.
The terahertz light path module comprises a terahertz source, a diaphragm, an off-axis parabolic mirror, a first beam splitter, a lens, a first detector, a first reflector and a second reflector; the terahertz source emits terahertz light, the intensity of the light beam is adjusted through the diaphragm, collimation is achieved after the terahertz light reaches the off-axis parabolic mirror, the terahertz light is divided into transmission light and reflection light at the first beam splitter, the transmission light and the reflection light reach the first beam splitter after being reflected by the first reflecting mirror and the second reflecting mirror respectively to achieve beam combination, and the light beam is converged at the lens and then directly enters the first detector.
The laser light path module comprises a laser, a collimating mirror, a second beam splitter, a second detector, a third reflector and a fourth reflector; laser emitted by the laser is divided into reflected light and transmitted light at the second beam splitter after the collimation of the light beam is optimized by the collimating mirror, and the reflected light and the transmitted light reach the second beam splitter after being reflected by the third reflecting mirror and the fourth reflecting mirror respectively to realize beam combination and are received by the second detector.
The moving platform is moved in one dimension by the fixed second reflector and the fixed third reflector.
And the computer is used for controlling the mobile platform to move and processing signals received by the first detector and the second detector, and calculating to obtain the terahertz wavelength.
Optionally, the moving platform drives the two fixed reflecting mirrors to move along the x axis of the horizontal direction of the guide rail at the same time, and the displacement of the two reflecting mirrors is the same.
Wherein, terahertz wavelength is obtained by mobile platform displacement volume and laser wavelength:
wherein N is0Number of stripe changes of laser beam path module, NTIs the fringe variation number, lambda, of the terahertz light path module0The wavelength of the laser emitted.
The invention provides a device for measuring and calibrating terahertz wavelength by improving, compared with the prior art, the following improvements and advantages:
1. the terahertz wavelength measuring device based on the Michelson interference type has the remarkable characteristics of low price, low use cost, simple and compact structure, simple light path and the like, realizes accurate measurement of terahertz wavelength, and is suitable for terahertz wavelength measurement with high stable frequency and narrow line width.
2. When the terahertz wavelength is measured, the position of the mobile platform is changed to drive the reflector to displace, so that interference signals generated by the combined beam on the detector periodically change along with the movement displacement of the reflector, and wavelength data can be obtained through calculation according to the Michelson interference principle. The terahertz wavelength measuring method can detect interference signals of laser and terahertz light simultaneously during working, can determine the terahertz wavelength according to the laser wavelength, the displacement of the mobile platform and the change number of interference fringes, and provides a novel terahertz wavelength measuring method.
3. When a laser transmitter with higher precision is used, the accuracy and the reliability of the measurement result can be further improved, so that the terahertz source can be traced.
Drawings
The invention is further explained below with reference to the figures and examples:
FIG. 1 is a diagram of a Michelson interference terahertz wavelength measurement optical system of the present invention;
Detailed Description
In order to explain the invention in detail, the technical solution in the embodiment of the invention will be clearly and completely explained below with reference to fig. 1. It should be understood that the described embodiments are only some of the embodiments of the present invention, and are not intended to limit the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Fig. 1 is a diagram of a michelson interference method terahertz wavelength two-way measurement optical system, specifically describing the position arrangement of each element and the construction of a light path, including a terahertz wavelength measurement module, a laser calibration module, a mobile platform and a computer. The terahertz light path module comprises a terahertz source 1, a diaphragm 2, an off-axis parabolic mirror 3, a first beam splitter 4, a lens 5, a first detector 6, a first reflector 7 and a second reflector 8; the terahertz source 1 emits terahertz light, the intensity of the light beam is adjusted through the diaphragm 2, collimation is achieved after the terahertz light reaches the off-axis parabolic mirror 3, the terahertz light is divided into transmitted light and reflected light at the first beam splitter 4, the transmitted light and the reflected light are reflected through the first reflecting mirror 7 and the second reflecting mirror 8 respectively and then reach the first beam splitter 4 to achieve beam combination, and the light beam is converged at the lens 5 and then directly enters the first detector 6.
The laser light path module comprises a laser 9, a collimating mirror 10, a second beam splitter 11, a second detector 12, a third reflector 13 and a fourth reflector 14; laser emitted by the laser 9 is divided into reflected light and transmitted light at the second beam splitter 11 after the collimation of the laser beam is optimized by the collimator 10, the reflected light and the transmitted light reach the second beam splitter 11 after being reflected by the third reflector 13 and the fourth reflector 14 respectively to realize beam combination, and the combined beams are received by the second detector 12.
The moving platform 15 is moved in one dimension by the fixed second reflector 7 and the fixed third reflector 13.
The computer is used for controlling the movement of the measuring moving platform 15, recording the displacement, processing signals received by the first detector 6 and the second detector 12, respectively recording the number of interference fringe change cycles generated by the terahertz light and the laser, and further calculating the terahertz wavelength.
The principle in the measurement process is as follows:
according to the Michelson interference principle, the position change of the second and third reflectors can change the optical path difference between the beam and the other beam when the beam reaches the beam splitter, so that the combined interference signal shows the change of intensity, and a waveform diagram is obtained by recording the position information of the reflectors and the voltage signal of the detector. The calculation formula of terahertz and laser wavelength is as follows:
where d is the moving distance of the mirror, and N is the number of cycles of the interference fringe variation.
In particular, there is a phenomenon that the interference fringes are incomplete at the start or end of the acquisition of the number of cycles of the variation of the interference fringes. In order to obtain accurate terahertz wavelength measurement data, incomplete stripes need to be counted in proportion, if a complete stripe needs to be obtained after a time t, and the time for an incomplete stripe is delta t, the corresponding incomplete stripe is counted as
The sum of the complete and incomplete fringe variations is N.
Known as λ0The computer can measure the number of the stripe changes of the laser light path module to be N for the laser wavelength emitted by the laser0The number of stripe changes of the terahertz light path module is NTThen, it can be deduced that the corresponding terahertz wavelength is:
preferably, the laser used in the present embodiment has a wavelength of 1550nm and a terahertz wavelength of 3mm, and has the characteristics of low loss and high transmission efficiency.
Through computer calculation, the measured number of the change cycles of the interference fringes of the laser is 2036.50, the number of the change cycles of the interference fringes of the terahertz is 1, and finally, the value of the terahertz wavelength is deduced to be
The instrument used in the invention has simple structure and few optical components; the stepping motor is utilized to drive the mobile platform to displace, so that automatic detection of the wavelength of the light beam is realized, and compared with manual detection, experimental errors are reduced, and the result is more visual and accurate; the method for measuring the terahertz wavelength through the laser provides a new mode for tracing the terahertz wavelength.
The above-described embodiments are merely illustrative of the principles and main advantages of the present invention, and the scope of the present invention is not limited thereto. All changes and substitutions based on the invention are included in the protection scope of the invention.
Claims (3)
1. A terahertz wavelength two-way measuring device based on Michelson interference is characterized by comprising a terahertz light path module, a laser light path module, a mobile platform and a computer;
the terahertz light path module comprises a terahertz source (1), a diaphragm (2), an off-axis parabolic mirror (3), a first beam splitter (4), a lens (5), a first detector (6), a first reflector (7) and a second reflector (8); the terahertz source (1) emits terahertz light, the intensity of the light beam is adjusted through the diaphragm (2), collimation is achieved after the terahertz light reaches the off-axis parabolic mirror (3), the terahertz light is divided into transmitted light and reflected light at the first beam splitter (4), the transmitted light and the reflected light reach the first beam splitter (4) after being reflected by the first reflector (7) and the second reflector (8) respectively to achieve beam combination, the light beam at the lens (5) is converged and then directly enters the first detector (6), and real-time interference fringes are collected;
the laser light path module comprises a laser (9), a collimating mirror (10), a second beam splitter (11), a second detector (12), a third reflector (13) and a fourth reflector (14); laser emitted by a laser (9) is divided into reflected light and transmitted light at a second beam splitter (11) after the collimation of a light beam is optimized by a collimating mirror (10), the reflected light and the transmitted light reach the second beam splitter (11) after being reflected by a third reflector (13) and a fourth reflector (14) respectively to realize beam combination, and a second detector (12) receives generated interference fringes;
the moving platform (15) moves in one dimension by using the fixed second reflecting mirror (7) and the fixed third reflecting mirror (13);
the computer is used for controlling the moving platform (15) to move and processing signals received by the first detector (6) and the second detector (12), and terahertz wavelength is obtained through calculation.
2. The device for measuring terahertz wavelength in two ways based on michelson interference according to claim 1, wherein the moving platform (15) drives the two fixed mirrors to move along x axis of the horizontal direction of the guide rail at the same time, and the displacement of the two mirrors is the same.
3. The device according to claim 1, wherein the terahertz wavelength is obtained from the displacement of the movable platform and the laser wavelength:
wherein N is0Number of stripe changes of laser beam path module, NTIs the fringe variation number, lambda, of the terahertz light path module0The wavelength of the laser emitted.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011228186.8A CN112414566A (en) | 2020-11-06 | 2020-11-06 | Terahertz wavelength double-path measuring device based on Michelson interference |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011228186.8A CN112414566A (en) | 2020-11-06 | 2020-11-06 | Terahertz wavelength double-path measuring device based on Michelson interference |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN112414566A true CN112414566A (en) | 2021-02-26 |
Family
ID=74827940
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011228186.8A Pending CN112414566A (en) | 2020-11-06 | 2020-11-06 | Terahertz wavelength double-path measuring device based on Michelson interference |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112414566A (en) |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2010117255A (en) * | 2008-11-13 | 2010-05-27 | Denso Corp | Spectroscopic device and spectroscopy method |
| US20170010162A1 (en) * | 2014-02-07 | 2017-01-12 | Hitachi High-Technologies Corporation | Terahertz Wave Phase Difference Measurement Device |
-
2020
- 2020-11-06 CN CN202011228186.8A patent/CN112414566A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2010117255A (en) * | 2008-11-13 | 2010-05-27 | Denso Corp | Spectroscopic device and spectroscopy method |
| US20170010162A1 (en) * | 2014-02-07 | 2017-01-12 | Hitachi High-Technologies Corporation | Terahertz Wave Phase Difference Measurement Device |
Non-Patent Citations (7)
| Title |
|---|
| 刘楚等: "迈克尔逊干涉法精确测量太赫兹频谱及目标速度", 《红外与激光工程》, vol. 47, no. 11, pages 1117006 - 2 * |
| 吕涛等: "一种光纤组量程扩增的激光频率 扫描干涉绝对测距系统", 《西安交通大学学报》, vol. 47, no. 9, pages 79 * |
| 林晓艳等: "用于面形测量的光纤投影器相移和频移特性", 《光学技术》, vol. 35, no. 01, pages 27 * |
| 王利强,左爱斌,彭月祥: "光波长测量仪器的分类、原理及研究进展", 科技导报, no. 06 * |
| 邓忠文等: "新型可调谐外腔半导体激光器光频扫描干涉测距方法", 《西安交通大学学报》, vol. 47, no. 5, pages 2 - 3 * |
| 陈本永等: "一种新型的干涉条纹软件计数方法及其实现研究", 《传感技术学报》, no. 03, pages 372 * |
| 陈本永等: "激光频率(波长)测量技术研究现状及发展", 《激光杂志》, vol. 30, no. 2, pages 2 * |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| EP2606311B1 (en) | Apparatus and method for measuring distance | |
| CN101832821B (en) | Method and device for measuring laser wavelength based on bound wavelength | |
| CN110411335A (en) | Differential type sinusoidal phase modulation laser interference surface nanometer-displacement device and method | |
| CN106247954B (en) | A kind of femtosecond laser measuring motion and method based on frequency conversion principle of interference | |
| US4969736A (en) | Integrated fiber optic coupled proximity sensor for robotic end effectors and tools | |
| CN1333230C (en) | Laser feedback nano displaycement measuring device | |
| CN103364775A (en) | Optical frequency comb calibration-based dual-color laser scanning absolute distance measuring device and method | |
| CN101413783A (en) | Double-frequency laser interference measuring device | |
| CN107576285B (en) | Laser mixes micro angle measurement system and measurement method certainly | |
| CN109239726B (en) | Non-cooperative target ranging system based on single double-comb femtosecond laser | |
| CN105203031A (en) | Quadruple optical subdivision two-axis heterodyne grating interferometer | |
| CN103439010A (en) | Wavelength measurement method and device based on laser synthesized wavelength interference principle | |
| CN105044035A (en) | Spectral domain interferometer-based refractive index and thickness synchronous measurement method and system thereof | |
| CN105333815A (en) | Super lateral resolution surface three-dimensional online interference measuring system based on spectral dispersion line scanning | |
| US5394240A (en) | High-accuracy air refractometer utilizing two nonlinear optical crystal producing 1st and 2nd second-harmonic-waves | |
| CN205003080U (en) | Refracting index and thickness synchronous measurement system based on spectral domain interferometer | |
| CN106370111A (en) | Variable frequency phase measurement principle-based femtosecond laser length measuring device and method | |
| CN201637492U (en) | Laser wavelength measuring device based on synthetic wavelength | |
| CN112414566A (en) | Terahertz wavelength double-path measuring device based on Michelson interference | |
| CN114894123B (en) | High-precision optical wedge angle measuring device and measuring method thereof | |
| CN100451581C (en) | Method and apparatus for measuring laser wave-length using heterodyne in interference method | |
| Wei et al. | Measurement accuracy of the pulse repetition interval-based excess fraction (PRIEF) method: an analogy-based theoretical analysis | |
| Sokolov et al. | Femtosecond laser-based absolute rangefinder with the possibility of traceability to the time and frequency standard | |
| CN110006356B (en) | Real-time calibration device and method based on SS-OCT (SS-OCT) distance measurement system | |
| CN204757922U (en) | Comparison type anti -interference fine motion cascading ladder corner reflection mirror laser interferometer |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20210226 |