阅读说明：本技术 一种实时波长匹配单色仪与波长监控系统 (Real-time wavelength matching monochromator and wavelength monitoring system ) 是由 余德良 陈文锦 于 2018-07-27 设计创作，主要内容包括：本发明公开了一种实时波长匹配单色仪与波长监控系统,窄带干涉滤光片设在高速旋转台上,光平行透镜和非球面成像透镜分别设置在窄带干涉滤光片的两侧,光平行透镜的外侧设置有入射端光纤,非球面成像透镜的外侧设置有雪崩二极管探测器,入射端光纤与光谱仪连接,雪崩二极管探测器与信号采集与存储系统连接,旋转台与旋转台控制器连接,中性束能量信号通过一个隔离放大器连接到旋转台控制器,远程控制平台与光谱仪和旋转台控制器连接。其优点是：可靠性好,稳定性高；不仅可以满足不同轮次实验中性束能量变化的波长匹配,而且在同一轮实验中可以使用中性束能量信号对滤光片中心波长进行实时匹配。(The invention discloses a real-time wavelength matching monochromator and a wavelength monitoring system.A narrow-band interference filter is arranged on a high-speed rotating platform, a light parallel lens and an aspheric imaging lens are respectively arranged at two sides of the narrow-band interference filter, an incident end optical fiber is arranged at the outer side of the light parallel lens, an avalanche diode detector is arranged at the outer side of the aspheric imaging lens, the incident end optical fiber is connected with a spectrometer, the avalanche diode detector is connected with a signal acquisition and storage system, the rotating platform is connected with a rotating platform controller, a neutral beam energy signal is connected with the rotating platform controller through an isolation amplifier, and a remote control platform is connected with the spectrometer and the rotating platform controller. The advantages are that: the reliability is good, and the stability is high; the method not only can meet the wavelength matching of the energy change of the neutral beam in different experiments, but also can match the central wavelength of the optical filter in real time by using the energy signal of the neutral beam in the same experiment.)

1. The utility model provides a real-time wavelength matching monochromator and wavelength monitored control system which characterized in that: the device comprises an incident end optical fiber (1), a light parallel lens (2), a narrow-band interference filter (3), a high-speed rotating platform (4), an aspheric imaging lens (5), an avalanche diode detector (6), a signal acquisition and storage system (7), a neutral beam energy signal (8), an isolation amplifier (9), a rotating platform controller (10), a spectrometer (11) and a remote control platform (12), wherein the narrow-band interference filter (3) is arranged on the high-speed rotating platform (4), the light parallel lens (2) and the aspheric imaging lens (5) are respectively arranged on two sides of the narrow-band interference filter (3), the incident end optical fiber (1) is arranged on the outer side of the light parallel lens (2), the avalanche diode detector (6) is arranged on the outer side of the aspheric imaging lens (5), the incident end optical fiber (1) is connected with the spectrometer (11), the avalanche diode detector (6) is connected with the signal acquisition and storage system (7), the rotating platform (4) is connected with a rotating platform controller (10), the neutral beam energy signal (8) is connected with the rotating platform controller (10) through an isolation amplifier (9), and the remote control platform (12) is connected with the spectrometer (11) and the rotating platform controller (10).

2. The real-time wavelength matching monochromator and wavelength monitoring system of claim 1, wherein: the narrow-band interference filter (3) is arranged on a high-speed rotating platform (4) with a grating ruler for positioning.

3. The real-time wavelength matching monochromator and wavelength monitoring system of claim 1, wherein: the remote control platform (12) is connected with the spectrometer (11) and the rotating platform controller (10) through the Ethernet.

4. The real-time wavelength matching monochromator and wavelength monitoring system of claim 1, wherein: the half-width of the narrow-band interference filter (3) is only 0.12-0.18 nm.

5. The real-time wavelength matching monochromator and wavelength monitoring system of claim 1, wherein: the incident end optical fiber (1) is connected with the spectrometer (11) through an optical fiber.

Technical Field

The invention belongs to the field of spectral measurement, and particularly relates to a real-time wavelength matching monochromator and a wavelength monitoring system for solving random Doppler frequency shift, which are mainly applied to visible spectrum diagnosis of neutral beam emission.

Background

In the controlled nuclear fusion experimental research of the straight line, the magnetic confinement device for confining plasma is mainly a Tokamak device. A dynamic stark polarimeter, one of the systems for plasma diagnostics based on Neutral Beam (NBI), can be used to measure the magnetic field structure inside the plasma, a parameter that is of great importance for the physical study of the plasma. The dynamic stark polarimeter has a filtering system for filtering the target spectral line. Monochromator systems with optical filters as the core are widely used internationally.

The target spectral line is characterized by doppler shift, a very narrow spectral line, and interference of many other spectral lines nearby. This requires that the filter center wavelength be much more accurate than the target spectral line wavelength matching for a typical monochromator. Due to the Doppler effect, the energy change of the neutral beam causes the wavelength of the target spectral line to change, and the central wavelength of the optical filter must change at the moment so as to ensure that the central wavelength of the optical filter is matched with the wavelength of the target spectral line.

There are two general methods internationally. The method comprises the following steps: and a plurality of optical filters with different central wavelengths are adopted, and when the energy change of the neutral beam causes the target spectral line to move, the optical filters with the central wavelengths consistent with the wavelength of the target spectral line are selected to be installed for filtering. The method 2 comprises the following steps: according to the characteristic that the central wavelength of the optical filter can move along with the temperature change, the aim of matching the central wavelength of the optical filter with a target spectral line is achieved by changing the temperature.

The method 1 adopts mechanical replacement of the optical filter, and the method can only solve the problem of the change of the neutral beam energy in different experiments but cannot solve the problem of the change of the neutral beam energy in the period of one experiment, so that the continuity of the one experiment is damaged. Meanwhile, the narrow-band filters are expensive, and manufacturing multiple filters increases the cost of the system [ document 1 ].

Secondly, the experimental process of the conventional magnetic confinement device only lasts for about 2-10 seconds, so that the relaxation time of the central wavelength of the temperature control optical filter is longer, and is about in the magnitude of minutes. Therefore, this method can only solve the problem of the change of the energy of the neutral beam in different experiments, but cannot solve the problem of the change of the energy of the neutral beam in one experiment, and cannot achieve the real-time wavelength matching [ document 2 ].

Document 1[ The master mechanical Stark effect diagnostic, Rev. Sci. Instrum.81,10D738(2010) ] is a dynamic Stark polarimeter on The MAST fusion device of The Kalam polytropic energy research centre, great Britain. The filtering system adopts a method of replacing the filter. The MAST fusion device only aims at the energy change of neutral beams in different experiments, and meanwhile, the paper also indicates that the development of a multi-channel system is limited by expensive optical filters.

Document 2[ A mechanical Stark effect Instrument to measure q (R) on the C-modtokamak, Rev. Sci. Instrument.72, 1012(2001) ] is a dynamic Stark polarizer on the C-MOD fusion device of the national institute of technology and technology. The filtering system adopts a method of controlling the central wavelength of the filter by temperature.

Disclosure of Invention

The invention aims to provide a real-time wavelength matching monochromator and a wavelength monitoring system, which can realize the real-time matching of the central wavelength of a narrow-band filter and the wavelength of a target spectral line under the condition that the target spectral line has random Doppler frequency shift, and meanwhile, the real-time monitoring system can monitor the matching condition.

The technical scheme of the invention is as follows: a real-time wavelength matching monochromator and wavelength monitoring system comprises an incident end optical fiber, an optical parallel lens, a narrow band interference filter, a high-speed rotating platform, an aspheric imaging lens, an avalanche diode detector, a signal acquisition and storage system, a neutral beam energy signal, an isolation amplifier, a rotating platform controller, a spectrometer and a remote control platform, wherein the narrow band interference filter is arranged on the high-speed rotating platform, the optical parallel lens and the aspheric imaging lens are respectively arranged at two sides of the narrow band interference filter, the incident end optical fiber is arranged at the outer side of the optical parallel lens, the avalanche diode detector is arranged at the outer side of the aspheric imaging lens, the incident end optical fiber is connected with the spectrometer, the avalanche diode detector is connected with the signal acquisition and storage system, the rotating platform is connected with the rotating platform controller, the neutral beam energy signal is connected with the rotating platform controller, the remote control platform is connected with the spectrometer and the rotating platform controller.

The narrow-band interference filter is arranged on a high-speed rotating platform with a grating ruler for positioning.

The remote control platform is connected with the spectrometer and the rotating platform controller through the Ethernet.

The half-height width of the narrow-band interference filter is only 0.12-0.18 nm.

The incident end optical fiber is connected with the spectrometer through the optical fiber.

The invention has the beneficial effects that: 1. the system has good reliability and high stability; 2. the wavelength matching of the energy change of the neutral beam in different experiments can be met, and the energy signal of the neutral beam can be used for matching the central wavelength of the optical filter in real time in the same experiment; 3. the system is additionally provided with a wavelength monitoring system, and the accuracy of the measured data is ensured.

Drawings

FIG. 1 is a schematic diagram of a real-time wavelength matching monochromator and wavelength monitoring system according to the present invention;

FIG. 2 is a flow chart of a real-time control system for a monochromator.

In the figure, 1 an incident end optical fiber, 2 optical parallel lenses, 3 narrow-band interference filters, 4 a high-speed rotating platform, 5 aspheric imaging lenses, 6 avalanche diode detectors, 7 a signal acquisition and storage system, 8 neutral beam energy signals, 9 an isolation amplifier, 10 a rotating platform controller, 11 a spectrometer and 12 a remote control platform.

Detailed Description

The invention is described in further detail below with reference to the figures and the embodiments.

The technical problem to be solved by the invention is as follows: the target spectral line wavelength is doppler shifted due to the neutral beam energy. Particularly in one round of experiment, random change of neutral beam energy causes random Doppler shift of target spectral line wavelength, which can cause the central wavelength of the optical filter not to match with the target spectral line wavelength. Therefore, a monochromator system which guides the movement of the central wavelength of the optical filter in real time by using a neutral beam energy signal and ensures the real-time matching of the central wavelength of the optical filter and the wavelength of a target spectral line needs to be developed, and a system which monitors the matching of the wavelengths in real time is provided.

As shown in fig. 1, a real-time wavelength matching monochromator and wavelength monitoring system includes an incident end optical fiber 1, a light parallel lens 2, a narrow-band interference filter 3, a high-speed rotary stage 4, an aspheric imaging lens 5, an avalanche diode detector 6, a signal acquisition and storage system 7, a neutral beam energy signal 8, an isolation amplifier 9, a rotary stage controller 10, a spectrometer 11, and a remote control platform 12.

The narrow-band interference filter 3 is installed on a high-speed rotating platform 4 with a grating ruler for positioning, the optical parallel lens 2 and the aspheric imaging lens 5 are respectively arranged on two sides of the narrow-band interference filter 3, the outer side of the optical parallel lens 2 is provided with an incident end optical fiber 1, the outer side of the aspheric imaging lens 5 is provided with an avalanche diode detector 6, the incident end optical fiber 1 is connected with a spectrometer 11 through an optical fiber, the avalanche diode detector 6 is connected with a signal acquisition and storage system 7, the rotating platform 4 is connected with a rotating platform controller 10, a neutral beam energy signal 8 is connected with the rotating platform controller 10 through an isolation amplifier 9, and a remote control platform 12 is connected with the spectrometer 11 and the rotating platform controller 10 through an Ethernet.

The filtering part of the monochromator adopts a narrow-band interference filter 3, and the full width at half maximum is only 0.12-0.18 nm. The central wavelength of the filter is shifted by changing the included angle between the narrow-band interference filter and the incident light. The narrow-band interference filter is arranged on a one-dimensional rotating platform 4, and the rotating platform drives the filter to rotate, so that the included angle between the filter and incident light is changed. The rotating platform is provided with a grating ruler part, and the included angle between the optical filter and incident light can be accurately obtained through the grating ruler, so that the central wavelength of the optical filter can be obtained.

The system directly controls a rotating platform controller through a neutral beam energy signal to guide the central wavelength of the optical filter to move in real time according to a specific relation. The specific relationship is the relationship between the energy signal of the neutral beam and the rotation angle, and needs to be calibrated by experiments. The neutral beam energy signal is led out from a high-voltage platform of the accelerator with the voltage of about 40 kilovolts, the high-voltage signal needs to be converted into a collectable-5 volt analog signal, and meanwhile, an isolation amplifier with specific parameters is adopted for isolation, so that the rotating table controller is prevented from being influenced or even damaged because the signal does not have a common grounding end in the transmission process.

The neutral beam energy signal directs the controller of the rotating platform, and the remote control is implemented by a remote system. The system adopts MATLAB language to compile and connect through Ethernet to communicate. This can be done away from fusion radiation injury.

The system pulls an optical fiber out of an incident end optical fiber and connects the optical fiber to a spectrometer for wavelength monitoring. The accuracy of data during each experiment is ensured by comparing the set wavelength of the controller with the position information of the target spectral line during the experiment.

The working process of the invention is as follows:

the target spectral line is input from the incident end optical fiber 1 and forms a beam of parallel light through the light parallel lens 2. The parallel light is filtered by a narrow-band interference filter 3. The narrow-band interference filter 3 is arranged on a high-speed rotating platform 4 with a grating ruler for positioning. The target spectral line filtered by the narrow-band interference filter 3 is converged to an avalanche diode detector 6 through an aspheric imaging lens 5 for photoelectric conversion, and finally data is stored by a signal acquisition and storage system 7.

The high-voltage signal of the neutral beam accelerator is converted into a signal of-5 to +5V, namely a neutral beam energy signal 8, which can be acquired by adopting a voltage-frequency voltage VF-FV conversion technology. The neutral beam energy signal 8 is connected to a rotary table controller 10 via an isolation amplifier 9. The turntable controller 10 guides the turntable 4 to rotate the optical filter 3. And the incident end optical fiber 1 is drawn to form an optical fiber which is connected with the spectrometer 11 to monitor the target spectral line. The remote control platform 12 performs remote control and data detection on the spectrometer 11 and the turntable controller 10 through ethernet.

Real-time wavelength matching monochromator the real-time control system flow diagram for the monochromator shown in figure 2. The system is triggered by a TTL signal, and the neutral beam energy signal is input into the rotating platform controller in real time. The neutral beam energy signal has a specific relationship to the angle of rotation. The rotating platform is guided to rotate the optical filter through the specific relation, and the central wavelength of the optical filter is matched with the target spectral line in real time. And if the experiment is finished in the current round, returning the real-time control system to the initial position, and waiting for triggering of the next round of TTL signals.