Device for detecting vacuum ultraviolet spectrum

Abstract

The invention provides a vacuum ultraviolet spectroscopy detecting device, which belongs to the field of spectrum analysis. The device includes: an entrance slit (2), a concave grating (3), a optical fiber array (4) and a flat plate detector (5). The entrance slit (2) and concave grating (3) are fixed in the vacuum cavity (1), one head face of the optical fiber array (4) coincides with the Rowland circle determined by the entrance slit (2) and the concave grating (3). The head face of the optical fiber array (4) is painted with fluorescent substance which can transform vacuum ultraviolet light into visible light, the other end face bifurcates into a number of sub-optical fiber arrays, and the end face of the sub-optical fiber array is a plain face and is connected with one flat plate detector (5). The device can measure vacuum ultraviolet spectroscopy within a certain range of wavelength simultaneously, and achieve the optical spectrum and pixel resolution of glancing incidence grating vacuum ultraviolet spectrometer, the testing time responses well and the device has high sensitivity; the moveable component is not needed in the vacuum cavity, and the structure is simple and reliable.

Description

technical field [0001] The invention relates to a detection device for vacuum ultraviolet (VUV) radiation and VUV band atomic emission spectrum, which belongs to the detection instrument in the field of spectrum analysis. Background technique [0002] To understand the behavior of impurity components in fusion plasma, the most basic method is to study them through the characteristic lines of various nuclides in the emission spectrum. For a typical magnetic confinement nuclear fusion experimental device, the plasma discharge conditions are roughly 1019-1020m-3 electron density and 0.1-10keV electron temperature. At this time, most of the spectral lines emitted by impurity nuclides (ions) are vacuum ultraviolet light in the wavelength range of 1-200nm. Therefore, detection of emission spectra in this range is the main means for us to diagnose impurities under the premise of ensuring the following conditions: First, the simultaneous detection of spectra must be ensured, that i...

AI Technical Summary

Problems solved by technology

However, despite the advantages of high efficiency, the traditional grazing incidence spectrometer has some problems in cooperating with the flat panel detector: in fact, after the incident light is split and focused by the grating, its focal point is not on the same plane, but is distributed on the Rowland disk

However, as far as the ring grating detection system currently in use is concerned: its focal length is relatively short (typically no more than 250mm, while the grazing incidence system can reach more than 2000mm), which leads to lower resolution; its imaging area is also small , the spatial density of the detector unit cannot be very high, which in turn leads to lower pixel resolution; in addition, the wavelength range covered by each ring grating is also small, so that it takes about 4 ring gratings to cover the wavelength range of 1-200nm grating (grazing incidence system can use only one grating)

[0006] In addition, there is another way to move the detector along the Rowland circle to scan light of different wavelengths, such as the vacuum ultraviolet spectrometer used to study some low-temperature plasmas with long-term stable discharges, but this cannot meet the requirements of the fusion plasma research. Basic Time Response Requirements

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