CN113739917B - Optical spectrum measuring system based on rotary optical fiber - Google Patents
Optical spectrum measuring system based on rotary optical fiber Download PDFInfo
- Publication number
- CN113739917B CN113739917B CN202111009157.7A CN202111009157A CN113739917B CN 113739917 B CN113739917 B CN 113739917B CN 202111009157 A CN202111009157 A CN 202111009157A CN 113739917 B CN113739917 B CN 113739917B
- Authority
- CN
- China
- Prior art keywords
- optical
- optical fiber
- light
- fiber
- analyzer
- 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.)
- Active
Links
- 239000013307 optical fiber Substances 0.000 title claims abstract description 52
- 230000003287 optical effect Effects 0.000 title claims abstract description 41
- 238000001228 spectrum Methods 0.000 title claims abstract description 25
- 238000005259 measurement Methods 0.000 claims abstract description 18
- 230000003595 spectral effect Effects 0.000 claims abstract description 17
- 238000009987 spinning Methods 0.000 claims abstract description 14
- 230000010287 polarization Effects 0.000 claims abstract description 13
- 230000009471 action Effects 0.000 claims abstract description 9
- 239000000835 fiber Substances 0.000 claims description 24
- 239000006185 dispersion Substances 0.000 claims description 16
- 230000005540 biological transmission Effects 0.000 claims description 4
- 230000007246 mechanism Effects 0.000 claims description 4
- 238000004611 spectroscopical analysis Methods 0.000 claims 4
- 230000000694 effects Effects 0.000 description 5
- 239000000463 material Substances 0.000 description 2
- 238000005070 sampling Methods 0.000 description 2
- 238000004458 analytical method Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000004364 calculation method Methods 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000003891 environmental analysis Methods 0.000 description 1
- 230000004907 flux Effects 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000011159 matrix material Substances 0.000 description 1
- 238000000691 measurement method Methods 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000009022 nonlinear effect Effects 0.000 description 1
- 230000000704 physical effect Effects 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 238000010183 spectrum analysis Methods 0.000 description 1
- 239000000126 substance Substances 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
- G01J3/00—Spectrometry; Spectrophotometry; Monochromators; Measuring colours
- G01J3/28—Investigating the spectrum
- G01J3/30—Measuring the intensity of spectral lines directly on the spectrum itself
-
- 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
- G01J3/00—Spectrometry; Spectrophotometry; Monochromators; Measuring colours
- G01J3/02—Details
- G01J3/0205—Optical elements not provided otherwise, e.g. optical manifolds, diffusers, windows
- G01J3/0218—Optical elements not provided otherwise, e.g. optical manifolds, diffusers, windows using optical fibers
-
- 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
- G01J3/00—Spectrometry; Spectrophotometry; Monochromators; Measuring colours
- G01J3/02—Details
- G01J3/0205—Optical elements not provided otherwise, e.g. optical manifolds, diffusers, windows
- G01J3/0224—Optical elements not provided otherwise, e.g. optical manifolds, diffusers, windows using polarising or depolarising elements
Abstract
The invention belongs to the related technical field of spectrometers, and discloses a spectral measurement system based on a spinning optical fiber. The measuring system comprises an optical filter, a polarizer, a rotary optical fiber, an analyzer and a power meter, wherein the optical filter enables light with a specific frequency spectrum in the light to be measured to pass through; the light passing through the optical filter is changed into linearly polarized light under the action of the polarizer, the optical fiber is arranged behind the optical filter, the linearly polarized light enters the optical fiber and is dispersed on the cross section of the optical fiber according to the polarization azimuth angle of the optical fiber, namely, the monochromatic light of each frequency component is dispersed and distributed along the circumferential direction in space; the analyzer is arranged behind the rotary optical fiber, rotates at a preset step angle, and couples light energy into a power meter arranged behind the analyzer, the power meter is used for measuring total optical power at each rotation angle, and the optical power meter is used for obtaining the spectrum of the light to be measured. The invention solves the problems of low measurement resolution and large size of the existing spectrometer.
Description
Technical Field
The invention belongs to the related technical field of spectrometers, and particularly relates to a spectral measurement system based on a spinning optical fiber.
Background
A Spectrometer (Spectrometer) is an optical instrument for qualitatively and quantitatively analyzing the composition and content of a substance by an optical principle, and is used as an indispensable tool for spectral analysis, and is applied to various fields such as biosensing, medical analysis, gas sensing, environmental analysis, oil exploration, food quality detection and the like. The existing spectrometers can be classified into three types, i.e., visible light type, infrared type and ultraviolet type spectrometers according to the wavelength ranges of light waves measured by the existing spectrometers, and can be mainly classified into prism dispersion type, grating dispersion type, fourier transform type and the like according to the light splitting mode of the existing spectrometers. The spectrometer based on the prism light splitting mainly utilizes different refractive indexes of light rays with different wavelengths in a prism material to realize dispersion, the resolution of the spectrometer is limited by the refractive index and the diffraction limit of the material, and the spectrometer based on the grating light splitting utilizes a grating as a dispersion element, and the resolution of the spectrometer is also limited by the grating density and the diffraction limit. Compared with a prism dispersion type spectrometer and a grating dispersion type spectrometer, the Fourier spectrometer has the advantages of high luminous flux, high spectral resolution and the like, and the theoretical resolution is infinite, so that the Fourier spectrometer is widely applied to various fields.
However, the fourier spectrometer needs a long movement distance in order to achieve high resolution, so that the size of the fourier spectrometer is usually large and the fourier spectrometer includes a moving element, and it is difficult to simultaneously satisfy the requirements of high spectral resolution and a compact structure.
Disclosure of Invention
In view of the above drawbacks and needs of the prior art, the present invention provides a fiber-spinning-based optical spectrum measurement system, which solves the problems of low measurement resolution and large size of the existing spectrometer.
To achieve the above object, according to the present invention, there is provided a spin-fiber based spectral measurement system comprising a filter, a polarizer, a spin fiber, an analyzer, and a power meter, wherein,
the optical filter is used for receiving light to be measured and enabling light with a specific frequency spectrum in the light to be measured to pass through; the polarizer is arranged behind the optical filter, light passing through the optical filter is changed into linearly polarized light under the action of the polarizer, the optical fiber is arranged behind the optical filter, the linearly polarized light enters the optical fiber and is dispersed on the cross section of the optical fiber according to the polarization azimuth angle of the optical fiber, and the monochromatic light of each frequency component is dispersed and distributed along the circumferential direction in space; the analyzer is arranged behind the rotary optical fiber, rotates at a preset step angle, and couples light energy into a power meter arranged behind the analyzer, the power meter is used for measuring total optical power at each rotation angle, and the optical power meter is used for obtaining the spectrum of the light to be measured.
Further preferably, the optical filter, the polarizer, the optical fiber, the analyzer and the power meter are coaxially distributed.
Further preferably, the optical power of the light collected in the power meter is calculated according to the following relation:
wherein, theta i Total angle of rotation, g (θ), after i rotations of the rotating device i ) Is at the total rotation angle theta i Optical power of lambda is the wavelength in the spectral range to be measured, lambda 1 Is the wavelength, λ, of the left boundary of the measured spectrum m Is the right end boundary wavelength of the measured spectrum, k (lambda) z is the rotation angle of the polarization azimuth angle of monochromatic light with different wavelengths after the action of the optical fiber with the length of z, k (lambda) is the dispersion coefficient of the optical fiber, theta 0 The included angle between the polarization direction of the polychromatic light and the transmission axis of the analyzer.
Further preferably, the length of the spiral optical fiber is adjusted according to the desired dispersion degree of the monochromatic light on the circumference.
Further preferably, the light to be measured is a narrowband polychromatic light.
Further preferably, the analyzer is disposed on a rotating mechanism, and the analyzer is rotated by the rotation of the rotating mechanism.
Further preferably, the filter is a band pass filter.
Further preferably, the length of the spiral pipeline is selected according to actual needs, and the required spiral fiber is in a linear or curved shape, so that light is ensured to enter from one end of the spiral fiber and output from the other end of the spiral fiber.
Generally, compared with the prior art, the technical scheme of the invention has the following beneficial effects:
1. the dispersion element adopted in the spectral measurement system provided by the invention is a spin high fiber (spin high fiber) and the theoretical resolution is almost infinite by using the polarization mode dispersion effect of the spin fiber after neglecting the physical effects such as polarization-related loss, transmission power loss, nonlinear effect and the like, more importantly, the spectral resolution capability can be continuously improved by increasing the length of the spin fiber, and the increase of the length of the spin fiber is very easy to realize in the manufacturing of an actual spectrometer; therefore, compared with the existing spectrometer, the spectral measurement system of the invention has high measurement precision, and the measurement precision can be adjusted by adjusting the length of the optical rotary fiber;
2. when the required optical fiber is long, the middle part of the optical fiber can be bent, and only the light is required to enter from one end of the optical fiber and output from the other end of the optical fiber, so that the whole measuring system occupies a small space even for the required long optical fiber, and compared with a Fourier spectrometer, the space size of the optical fiber is greatly reduced;
3. each part adopted in the invention has simple structure, does not need a larger moving element, and does not need longer movement distance in the measurement process, so that compared with the existing Fourier spectrometer, the Fourier spectrometer has more compact structure and smaller size.
Drawings
FIG. 1 is a schematic block diagram of a spin-fiber based spectral measurement system constructed in accordance with a preferred embodiment of the present invention;
fig. 2 is a schematic illustration of the effect of an optical fiber constructed according to a preferred embodiment of the present invention on polychromatic light.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention. In addition, the technical features involved in the embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.
As shown in fig. 1, a spectral measurement system based on a spin high fiber (optical fiber). The narrow-band polychromatic light source to be measured for the first time passes through a band-pass filter, light with a specific frequency spectrum passes through the band-pass filter, the light after the filter is converted into linearly polarized light through the polarizer, the linearly polarized light is coupled into the optical fiber, and the monochromatic components of the polychromatic light are distributed on the cross section of the output end of the optical fiber in a spatial circumferential manner through the dispersion effect of the optical fiber. Then the dispersed polychromatic light passes through an analyzer which is placed on a fixed rotating device, and the rotating device drives the analyzer to rotate at equal intervals with a certain step angle. Finally, the light energy after the action of the analyzer is coupled into an optical power meter, the total optical power under each rotation angle is measured, and the spectral details of the incident light source can be obtained after mathematical calculation.
The optical fiber spinning-based spectrometer and the spectral measurement method can realize the high-resolution measurement of the spectrum under a compact structure, have almost infinite resolution theoretically, and are particularly suitable for the measurement of narrow-band spectrum.
When the rotating device drives the analyzer to rotate at equal intervals with a fixed step angle, the step angle is set to be delta theta rad, and the polarization azimuth angle of the polarized light subjected to dispersion action of the optical fiber changes relative to the analyzer, so that the optical power detected by the optical power meter changes finally. If the spectral function of the incident light source is f (λ) and the spectral function after dispersion by the optical fiber is g (λ), the emergent light power after the action of the analyzer has the following functional relationship with the spectral function and the step angle of the incident light source:
wherein theta is 0 Is the angle theta between the polarization direction of the polychromatic light and the transmission axis of the analyzer i For the total angle of rotation of the rotary device after i times of rotation, i.e. theta i I Δ θ. k (λ) z is the rotation angle of polarization azimuth angle of monochromatic light with different wavelengths after the action of the optical fiber with length z, k (λ) is the dispersion coefficient of the optical fiber, the size of k (λ) is determined by the characteristic parameters of the optical fiber and the wavelength λ of the light wave, and k (λ) ═ k under a narrow spectrum width 0 + a λ. When the rotating device rotates once, the total optical power data, namely the number of sampling points, is equal to 2 pi/delta theta.
Equation (1) can be expressed in matrix form as:
the rotation-transposed pitch angle Δ θ is given during the measurement, and the unknowns in equation (2) above are k (λ #) 1 )z+θ 0 -k(λ m )z+θ 0 、f(λ 1 )-f(λ m ) And m determines the subdivision multiple of the incident light source spectrum, the total unknown number is 2m, and the equation theoretically has least square solution only by satisfying the total rotation times, namely the total sampling times n is more than 2m, and finally realizes the m-time subdivision of the light source spectrum.
The effect of the spin fiber on the polychromatic light is shown in fig. 2, the polarized polychromatic light is dispersed according to the polarization azimuth angle of the polarized polychromatic light on the cross section of the optical fiber through the effect of the spin fiber, that is, the monochromatic light of each frequency component is dispersed and distributed along the circumferential direction in space, and the longer the length of the spin fiber is, the more the spectrum of each frequency component is dispersed, so that even the spectrum with very narrow spectrum width can be dispersed through the enough long spin fiber, thereby detecting the spectrum.
It will be understood by those skilled in the art that the foregoing is only a preferred embodiment of the present invention, and is not intended to limit the invention, and that any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the scope of the present invention.
Claims (8)
1. The optical spectrum measuring system based on the spinning optical fiber is characterized by comprising an optical filter, a polarizer, the spinning optical fiber, an analyzer and a power meter, wherein,
the optical filter is used for receiving light to be measured and enabling light with a specific frequency spectrum in the light to be measured to pass through; the polarizer is arranged behind the optical filter, light passing through the optical filter is changed into linearly polarized light under the action of the polarizer, the optical fiber is arranged behind the optical filter, the linearly polarized light enters the optical fiber and is dispersed on the cross section of the optical fiber according to the polarization azimuth angle of the optical fiber, and the monochromatic light of each frequency component is dispersed and distributed along the circumferential direction in space; the analyzer is arranged behind the rotary optical fiber, rotates at a preset step angle, and couples light energy into a power meter arranged behind the analyzer, the power meter is used for measuring total optical power at each rotation angle, and the optical power meter is used for obtaining the spectrum of the light to be measured.
2. The optical rotary fiber-based spectrometry system of claim 1, wherein the optical filter, the polarizer, the optical rotary fiber, the analyzer and the power meter are coaxially disposed.
3. A spinning fiber based spectrometry system according to claim 1 or 2, wherein the optical power of the light collected in the power meter is calculated according to the following relationship:
wherein, theta i Total angle of rotation, g (θ), after i rotations of the rotating device i ) Is at the total rotation angle theta i Optical power of lambda is the wavelength in the spectral range to be measured, lambda 1 Is the wavelength, λ, of the left boundary of the measured spectrum m Is the right end boundary wavelength of the measured spectrum, k (lambda) z is the rotation angle of the polarization azimuth angle of monochromatic light with different wavelengths after the action of the optical fiber with the length of z, k (lambda) is the dispersion coefficient of the optical fiber, theta 0 The included angle between the polarization direction of the polychromatic light and the transmission axis of the analyzer.
4. A spinning-fiber based spectroscopic measurement system as set forth in claim 2 wherein the length of the spinning fiber is adjusted according to the desired degree of dispersion of the monochromatic light around the circumference.
5. The optical fiber spinning-based spectroscopic measurement system of claim 1 or 2 wherein the light to be measured is a narrowband polychromatic light.
6. The optical rotary fiber-based spectrometry system of claim 3, wherein the analyzer is disposed on a rotation mechanism, and the rotation of the rotation mechanism rotates the analyzer.
7. The optical rotary fiber-based spectrometry system of claim 3, wherein the filter is a bandpass filter.
8. The optical fiber spinning-based spectrum measuring system as claimed in claim 1 or 2, wherein the length of the spinning optical fiber is selected according to actual needs, and the required spinning optical fiber is in a linear or curved shape, so as to ensure that light enters from one end of the spinning optical fiber and is output from the other end of the spinning optical fiber.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111009157.7A CN113739917B (en) | 2021-08-31 | 2021-08-31 | Optical spectrum measuring system based on rotary optical fiber |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111009157.7A CN113739917B (en) | 2021-08-31 | 2021-08-31 | Optical spectrum measuring system based on rotary optical fiber |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113739917A CN113739917A (en) | 2021-12-03 |
| CN113739917B true CN113739917B (en) | 2022-08-05 |
Family
ID=78734075
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111009157.7A Active CN113739917B (en) | 2021-08-31 | 2021-08-31 | Optical spectrum measuring system based on rotary optical fiber |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113739917B (en) |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP3749646B2 (en) * | 2000-02-21 | 2006-03-01 | 独立行政法人科学技術振興機構 | Polarization mode dispersion measuring apparatus and polarization mode dispersion measuring method |
| JP3734667B2 (en) * | 2000-03-14 | 2006-01-11 | アンリツ株式会社 | Polarization mode dispersion measurement method and polarization mode dispersion measurement system |
| CN201368771Y (en) * | 2009-03-05 | 2009-12-23 | 谭成忠 | Broadband spectrometer |
| CN101493357B (en) * | 2009-03-05 | 2010-06-09 | 谭成忠 | Boradband spectrometer |
| CN103558157B (en) * | 2013-11-19 | 2015-10-28 | 上海理工大学 | Based on digital robotization optical rotational activity spectrum instrument and the method for testing of DSP |
-
2021
- 2021-08-31 CN CN202111009157.7A patent/CN113739917B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN113739917A (en) | 2021-12-03 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101105446B (en) | Differential optical absorption spectroscopy air quality detection system | |
| US8542357B2 (en) | Method and device for measuring circular dichroism spectra | |
| GB2254415A (en) | An optical sensor | |
| CN113654661B (en) | Spectrometer based on super-surface lens | |
| JPH01124723A (en) | Spectrograph | |
| CN107917680A (en) | Minute angle method for quickly identifying based on balzed grating, | |
| Chen et al. | Dual-resonance sensing for environmental refractive index based on quasi-BIC states in all-dielectric metasurface | |
| KR20080091002A (en) | Apparatus for measuring phase difference using spectrometer | |
| CN203719771U (en) | Spectral measurement apparatus based on elasto-optical effect | |
| CN113739917B (en) | Optical spectrum measuring system based on rotary optical fiber | |
| CN105911015B (en) | Broadband dielectric parameter acquisition methods based on multiple-beam interference effect | |
| CN105136299A (en) | Novel infrared spectrum inversion method based on PEM and device thereof | |
| CN114152339A (en) | Spectrum sensor based on geometric phase super-surface structure and spectrum reconstruction method | |
| CN101493357B (en) | Boradband spectrometer | |
| CN106940291B (en) | High-resolution double-grating monochromator light path device | |
| US11530955B2 (en) | Method for measuring gas temperature in plasma | |
| US11346778B1 (en) | Method for detecting petroleum with a staggered toroidal chip | |
| CN202195882U (en) | Fourier spectrometer without movable mechanical part | |
| CN201368771Y (en) | Broadband spectrometer | |
| CN103759831A (en) | Spectral measurement device and spectral measurement method based on elasto-optical effect | |
| CN110702230B (en) | Fourier transform spectrometer | |
| CN210863099U (en) | Device for measuring performance of broadband wave plate by using AOTF monochromatic light | |
| CN114812809A (en) | Broadband spectrum shaping device and calculation type spectrum measuring device | |
| Goncharenko et al. | Recording and analysis of the radiation spectrum in the infrared band by means of Bragg waveguide gratings | |
| Agarwal et al. | All Dielectric High Q-Factor Metasurface Refractive Index Sensor based on Dual Fano Resonances in THz Region |
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 | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |