CN108332945A - A kind of diffraction efficiency of grating test system and method - Google Patents
A kind of diffraction efficiency of grating test system and method Download PDFInfo
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- CN108332945A CN108332945A CN201711430637.4A CN201711430637A CN108332945A CN 108332945 A CN108332945 A CN 108332945A CN 201711430637 A CN201711430637 A CN 201711430637A CN 108332945 A CN108332945 A CN 108332945A
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- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
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Abstract
The invention discloses a kind of diffraction efficiency of grating to test system, including flying to include Wavelength tunable laser, polarization control component, light-dividing device and the rotatable diffraction element sequentially placed on optical axis along light path, further include two light energy detectors, wherein one coordinates with light-dividing device so that the reference beam separated from light-dividing device is directly entered the first light energy detector, and another coordinates with diffraction element so that the test beams separated from light-dividing device are incident on diffraction element and enter the second light energy detector after diffraction.The optical maser wavelength precision height of the present invention, line width, polarization direction is adjustable, can obtain spectrum, angle, the polarization characteristic of grating high-precision diffraction efficiency；Configuration principle is simple, easy to operate, and environmental suitability is strong.Meet the application demand in high power laser light and spectrum analysis field, is suitable for Spectral beam combining and spectrum analysis field.
Description
Technical field
The present invention relates to the field of optical measurements of diffraction efficiency of grating test, and in particular to a kind of diffraction efficiency of grating test
System and method.
Background technology
Spectral beam combining technology by multichannel narrow linewidth semiconductor, optical fiber or is consolidated using synthesizers such as gratings (diffraction element)
Volumetric laser synthesizes single channel high power, high brightness laser output.Spectral beam combining technology is to ensure to realize work(while beam quality
The effective means of rate energy lift, grating (diffraction element) is the key components of Spectral beam combining, to the diffraction of different wave length
Efficiency determines final synthetic effect, with the increase of synthesis way, is proposed to the diffraction efficiency measuring accuracy of accurate wavelength
Higher requirement.On the other hand, in scientific research spectrum analysis field, different wave length is accurately controlled by grating, realizes spectrum
Analysis, is the Primary Component of spectrometric instrument equipment, diffraction efficiency accuracy is the key index of instrument and equipment.
Diffraction efficiency high precision measurement method cannot accurately control incident fine wavelength, incident polarization at present,
Diffraction efficiency (diffraction light energy ratio incident laser energy, related with wavelength) cannot accurately be tested, high power laser light cannot be met
And the application demand in spectrum analysis field.
Invention content
To solve the above problems, the present invention provides a kind of diffraction efficiency of grating to test system, including sequentially exist along light path
Wavelength tunable laser, polarization control component, light-dividing device and the rotatable diffraction element placed on optical axis, further include two
Platform light energy detector, wherein one coordinates with the light-dividing device so that the reference beam separated from light-dividing device is directly entered
First light energy detector, another coordinates with the diffraction element so that the test beams separated from light-dividing device are incident on and spread out
It penetrates element and enters the second light energy detector after diffraction.
Specifically, the Wavelength tunable laser, work constitution are one kind in semiconductor, optical fiber, solid.
Specifically, the laser work wavelength that the Wavelength tunable laser is exported can be but not limited to
It 1000nm-1100 μm, is determined with specific reference to grating test demand, is light beam；Optical maser wavelength precision is less than 1nm, 3dB line widths
Less than 1nm.
Preferably, the polarization control component is half-wave plate.
Specifically, the eyeglass or one kind in wedge mirror, sampled-grating that the light-dividing device is certain splitting ratio.
Specifically, the diffraction element is one kind in plane balzed grating, body grating.
The present invention also provides the test methods of above-mentioned test system, include the following steps：
Step 1: sequentially placed on optical axis along light path Wavelength tunable laser, polarization control component, light-dividing device and
Rotatable diffraction element also places two light energy detectors, wherein one coordinates with the light-dividing device so that from light splitting
The reference beam that equipment separates is directly entered the first light energy detector, and another coordinates with the diffraction element so that from light splitting
The test beams that equipment separates are incident on diffraction element and enter the second light energy detector after diffraction.
Step 2: opening Wavelength tunable laser, the continuously adjustable narrow linewidth of wavelength, polarized laser beam, warp are generated
After crossing polarization control component, the polarization state of laser is controlled by rotatory polarization control element, fixation is then divided by light-dividing device
Two beam laser of energy ratio, reflected light and transmitted light, reflected light are tested out as being directly entered light energy detector with reference to light beam
Reflected energy；
Step 3: the transmitted light in step 2 is incident on as test beams on rotatable diffraction element, pass through rotation
Diffraction element is realized under the conditions of arbitrary incident angle to the incidence of diffraction element, and light energy detector is entered after diffraction, is surveyed
The energy for trying diffraction light, to calculate grating diffration efficiency.
Specifically, it is as follows that grating diffration efficiency method is calculated in the step 3：
The laser of Wavelength tunable laser output, is incident on half-wave plate, passes through sampled-grating, sampling rate χ, reference
Light beam is directly entered the first light energy detector, test incident laser energy P1；Test beams are incident on plane balzed grating, warp
Enter the second light energy detector after diffraction, the second light energy detector tests the energy P of diffraction light2；
Pass through the output wavelength of adjusting wavelength tunable laser, you can obtain plane balzed grating, to different wave length laser
Diffraction efficiency, be represented by：
That is diffraction efficiency of grating spectral characteristic.
The Wavelength tunable laser that the present invention tests systems approach produces the continuously adjustable narrow linewidth of wavelength, polarization swashs
Light light beam is controlled the polarization state of laser by rotatable halfwave plate, is then divided into fixed energies ratio by beam splitter after half-wave plate
Two beam laser, reflected light and transmitted light, the reflected beams power energy, which is used as, refers to energy；Transmitted light is incident on grating, is surveyed
The energy for trying diffraction light, to calculate grating diffration efficiency.Grating is can get by rotatable halfwave plate to swash different polarization states
The diffraction characteristic of light；By adjusting wavelength tunable laser shoot laser, diffraction characteristic of the grating to different wave length is obtained；It is logical
The angle of turntable is overregulated, diffraction characteristic, that is, diffraction efficiency of the grating under incidence angles degree is can get.
The present invention, which tests systems approach, can realize grating to the laser of different wave length, different polarization states in arbitrary incident angle
Under the conditions of diffraction efficiency.
It is optical maser wavelength precision height, line width, inclined in short, test system and method the present invention provides diffraction efficiency of grating
The direction that shakes is adjustable, can obtain spectrum, angle, the polarization characteristic of grating high-precision diffraction efficiency；Configuration principle is simple, operation side
Just, environmental suitability is strong.Test method is accurately controlled by incident wavelength, laser polarization, power capability is accurately tested, and gives light extraction
Grid meet the application demand in high power laser light and spectrum analysis field to the accurate diffraction efficiency of fine wavelength, are suitable for spectrum
Synthesis and spectrum analysis field.
Description of the drawings
Fig. 1 is the diffraction efficiency of grating measurement system diagram of the present invention.
Wherein：1- lasers, 2- half-wave plates, 3- sampled-gratings (light-dividing device), 41- the first light energy detectors, 42-
Two light energy detectors, 5- turntables, 6- plane balzed grating,s.
Specific implementation mode
In order to make the purpose , technical scheme and advantage of the present invention be clearer, with reference to the accompanying drawings and embodiments, right
The specific implementation mode of the present invention is described further.It should be appreciated that specific embodiment described herein is used only for helping
Understand the present invention, does not constitute limitation of the invention.In addition, involved in the various embodiments of the present invention described below
To technical characteristic can be combined with each other as long as they do not conflict with each other.
As shown in Figure 1, a kind of diffraction efficiency of grating tests system, including the wavelength sequentially placed on optical axis along light path can
Tuned laser, polarization control component, light-dividing device and rotatable diffraction element further include two light energy detectors,
In one coordinate with the light-dividing device so that the reference beam that is separated from light-dividing device is directly entered the first light energy detector,
Another coordinate with the diffraction element so that the test beams that are separated from light-dividing device to be incident on diffraction element laggard through diffraction
Enter the second light energy detector.Diffraction efficiency of grating, that is, diffraction light energy ratio incident laser energy, it is related with wavelength.
Wavelength tunable laser, work constitution are optical fiber.
The laser work wavelength that Wavelength tunable laser is exported can be but not limited to 1000nm-1100 μm, specifically
Require to determine according to grating test, the use demand of different gratings is different, grating be for ultraviolet light wave band as
200-300nm, grating be such as 400-700nm for visible light wave range, concrete condition is true according to the demand of test gratings
It is fixed, it is light beam；Optical maser wavelength precision is less than 1nm, and 3dB line widths are less than 1nm.The present embodiment wavelength is 1050-1100nm.
Polarization control component is half-wave plate.
Light-dividing device is the sampled-grating of certain splitting ratio (can be arbitrary), plated film or without plated film lens.
Diffraction element is rotatable plane balzed grating, is placed on rotatable turntable.Can also be other dispersions
Element.
The test method of the test system of the present invention, includes the following steps：
Step 1: sequentially placed on optical axis along light path Wavelength tunable laser, polarization control component, light-dividing device and
Rotatable diffraction element also places two light energy detectors, wherein one coordinates with the light-dividing device so that from light splitting
The reference beam that equipment separates is directly entered the first light energy detector, and another coordinates with the diffraction element so that from light splitting
The test beams that equipment separates are incident on diffraction element and enter the second light energy detector after diffraction.
Step 2: opening Wavelength tunable laser, the continuously adjustable narrow linewidth of wavelength, polarized laser beam, warp are generated
After crossing polarization control component, the polarization state of laser is controlled by rotatory polarization control element, fixation is then divided by light-dividing device
Two beam laser of energy ratio, reflected light and transmitted light, reflected light are tested out as being directly entered light energy detector with reference to light beam
The energy (power) of reflected light, energy (power) is the statement for continuous laser in the present invention；
Step 3: the transmitted light in step 2 is incident on as test beams on rotatable diffraction element, pass through rotation
Diffraction element is realized under the conditions of arbitrary incident angle to the incidence of diffraction element, and light energy detector is entered after diffraction, is surveyed
The energy (power) for trying diffraction light, to calculate grating diffration efficiency.
It is as follows to calculate grating diffration efficiency method：
The laser of Wavelength tunable laser output, is incident on polarization beat length element, passes through light-dividing device, sampling rate
For χ, reference beam is directly entered the first light energy detector, tests incident laser energy (power) P1；Test beams are incident on flat
On the balzed grating, of face, the second light energy detector is entered after diffraction, the second light energy detector tests the light energy of diffraction light
(power) P2；
Pass through the output wavelength of adjusting wavelength tunable laser, you can obtain plane balzed grating, to different wave length laser
Diffraction efficiency, be represented by：
That is diffraction efficiency of grating spectral characteristic.
Pass through rotatable half-wave plate, you can diffraction efficiency of the plane balzed grating, to different polarization state laser is obtained,
That is diffraction efficiency polarization characteristic.
The test system of the present invention further includes turntable, and plane balzed grating, is placed on a spinstand, is revolved by rotating
The angle of turntable changes the laser angle being incident on plane balzed grating, you can obtains plane balzed grating, to different incidences
The diffraction efficiency of multi-angle laser, i.e. diffraction efficiency angular characteristics.
The present invention is not only limited to above-mentioned specific implementation mode, and persons skilled in the art are according to disclosed by the invention interior
Hold, other a variety of specific implementation modes may be used and implement the present invention, therefore, every design structure using the present invention and think of
Road does some simple designs changed or change, both falls within the scope of protection of the invention.
Claims (8)
1. a kind of diffraction efficiency of grating tests system, it is characterised in that including the Wavelength tunable sequentially placed on optical axis along light path
Humorous laser, polarization control component, light-dividing device and rotatable diffraction element further include two light energy detectors, wherein
One coordinates with the light-dividing device so that the reference beam separated from light-dividing device is directly entered the first light energy detector, separately
One coordinates with the diffraction element so that the test beams that are separated from light-dividing device are incident on diffraction element enters after diffraction
Second light energy detector.
2. test system according to claim 2, it is characterised in that the Wavelength tunable laser, work constitution are
One kind in semiconductor, optical fiber, solid.
3. test system according to claim 3, it is characterised in that the Wavelength tunable laser was exported swashs
Light operation wavelength can be but not limited to 1000nm-1100 μm, require to determine with specific reference to grating test, be light beam；Swash
Optical wavelength precision is less than 1nm, and 3dB line widths are less than 1nm.
4. test system according to claim 1, it is characterised in that the polarization control component is half-wave plate.
5. test system according to claim 1, it is characterised in that the light-dividing device is the eyeglass of certain splitting ratio,
Or one kind in wedge mirror, sampled-grating.
6. test method according to claim 1, it is characterised in that the diffraction element is plane balzed grating, body light
One kind in grid.
7. the test method of the test system according to any one of claim 1~6, it is characterised in that including walking as follows
Suddenly：
Step 1: Wavelength tunable laser, polarization control component, light-dividing device are sequentially placed on optical axis along light path and can be revolved
The diffraction element turned also places two light energy detectors, wherein one coordinates with the light-dividing device so that from light-dividing device
The reference beam separated is directly entered the first light energy detector, and another coordinates with the diffraction element so that from light-dividing device
The test beams separated are incident on diffraction element and enter the second light energy detector after diffraction；
Step 2: opening Wavelength tunable laser, the continuously adjustable narrow linewidth of wavelength, polarized laser beam are generated, by inclined
It shakes after control element, the polarization state of laser is controlled by rotatory polarization control element, fixed energies are then divided by light-dividing device
Two beam laser of ratio, reflected light and transmitted light, reflected light test out reflection as being directly entered light energy detector with reference to light beam
Energy；
Step 3: the transmitted light in step 2 is incident on as test beams on rotatable diffraction element, pass through rotating diffraction
Element is realized under the conditions of arbitrary incident angle to the incidence of diffraction element, and light energy detector is entered after diffraction, and test is spread out
Penetrate the energy P of light2, to calculate grating diffration efficiency.
8. the test method of test system according to claim 7, it is characterised in that calculate grating in the step 3
Diffraction efficiency method is as follows：
The laser of Wavelength tunable laser output, is incident on polarization control component, passes through light-dividing device, sampling rate χ, ginseng
It examines light beam and is directly entered the first light energy detector, test incident laser energy P1；Test beams are incident on plane balzed grating,
Enter the second light energy detector after diffraction, the second light energy detector tests the energy P of diffraction light2；
Pass through the output wavelength of adjusting wavelength tunable laser, you can obtain plane balzed grating, and spread out to different wave length laser
Efficiency is penetrated, is represented by：
That is diffraction efficiency of grating spectral characteristic.
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Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN109407365A (en) * | 2018-12-13 | 2019-03-01 | 中国科学院上海光学精密机械研究所 | The measuring device and method of liquid crystal grating device diffraction efficiency under laser action |
| CN109883655A (en) * | 2019-01-31 | 2019-06-14 | 中国科学院上海光学精密机械研究所 | The measuring device and its measurement method of the DOE angle of diffraction |
| CN111766048A (en) * | 2020-07-28 | 2020-10-13 | 深圳先进技术研究院 | Automatic grating diffraction angle spectrum measuring system |
| CN112072457A (en) * | 2020-09-16 | 2020-12-11 | 中国科学院半导体研究所 | Intermediate infrared quantum cascade laser and difference frequency terahertz external cavity feedback light path structure |
| CN112097900A (en) * | 2020-11-10 | 2020-12-18 | 中国工程物理研究院激光聚变研究中心 | High-energy laser beam quality testing method and system |
| CN113218627A (en) * | 2021-03-26 | 2021-08-06 | 歌尔股份有限公司 | Grating diffraction efficiency testing device and method |
| CN113639860A (en) * | 2021-07-19 | 2021-11-12 | 中国科学院上海光学精密机械研究所 | Measuring device and measuring method for chirp volume grating frequency spectrum diffraction curve |
| CN113899533A (en) * | 2021-12-08 | 2022-01-07 | 杭州拓致光电科技有限公司 | Device and method for measuring performance of reflective volume grating |
| CN118090161A (en) * | 2024-03-27 | 2024-05-28 | 中国航天三江集团有限公司 | Grating diffraction efficiency and tolerance testing device and method |
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Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109407365A (en) * | 2018-12-13 | 2019-03-01 | 中国科学院上海光学精密机械研究所 | The measuring device and method of liquid crystal grating device diffraction efficiency under laser action |
| CN109883655A (en) * | 2019-01-31 | 2019-06-14 | 中国科学院上海光学精密机械研究所 | The measuring device and its measurement method of the DOE angle of diffraction |
| CN111766048A (en) * | 2020-07-28 | 2020-10-13 | 深圳先进技术研究院 | Automatic grating diffraction angle spectrum measuring system |
| CN111766048B (en) * | 2020-07-28 | 2022-04-22 | 深圳先进技术研究院 | Automatic grating diffraction angle spectrum measuring system |
| CN112072457A (en) * | 2020-09-16 | 2020-12-11 | 中国科学院半导体研究所 | Intermediate infrared quantum cascade laser and difference frequency terahertz external cavity feedback light path structure |
| CN112097900A (en) * | 2020-11-10 | 2020-12-18 | 中国工程物理研究院激光聚变研究中心 | High-energy laser beam quality testing method and system |
| CN113218627A (en) * | 2021-03-26 | 2021-08-06 | 歌尔股份有限公司 | Grating diffraction efficiency testing device and method |
| CN113639860A (en) * | 2021-07-19 | 2021-11-12 | 中国科学院上海光学精密机械研究所 | Measuring device and measuring method for chirp volume grating frequency spectrum diffraction curve |
| CN113899533A (en) * | 2021-12-08 | 2022-01-07 | 杭州拓致光电科技有限公司 | Device and method for measuring performance of reflective volume grating |
| CN113899533B (en) * | 2021-12-08 | 2022-04-01 | 杭州拓致光电科技有限公司 | Device and method for measuring performance of reflective volume grating |
| CN118090161A (en) * | 2024-03-27 | 2024-05-28 | 中国航天三江集团有限公司 | Grating diffraction efficiency and tolerance testing device and method |
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Application publication date: 20180727 |