Laser excitation spectrum detection probe and spectrum detection method

Abstract

The invention discloses a laser excitation spectrum detection probe and a spectrum detection method with the probe. The probe comprises a laser for outputting laser beams with different divergence angles in the long shaft direction and the short shaft direction, a light path converting device arranged on an output light path of the laser beams and used for changing a transmission path of incident light, a focusing collecting device for focusing beams reflected by the light path converting device to a focus containing with a sample and a coupling light-filtering device arranged between the light path converting device and a spectrograph and used for optical coupling the collected beams and then focusing the formed strip-type faculae at a slit of the spectrograph. By means of the laser excitation spectrum detection probe and the spectrum detection method with the probe, the coupling efficiency of the spectrograph can be improved, and the collecting efficiency of a system is improved; the cost of devices and the cost of instruments are reduced, and the tolerance performance of the system is improved; the power density of converging laser faculae is reduced, and heat accumulation and sample firing are prevented; the sampling range is widened, and the laser excitation spectrum detection probe is more suitable for sampling solid mixture samples and sparse samples.

Description

technical field [0001] The invention relates to the technical field of laser excitation spectrum detection, in particular to a laser excitation spectrum detection probe and a spectrum detection method. Background technique [0002] Laser excitation spectroscopy detection technology includes Raman spectroscopy, fluorescence spectroscopy, and plasma spectroscopy. Laser light sources are used as excitation light sources for these optical phenomena. comprehensive performance of the device. Spectrum analyzers based on gratings / prisms are currently the most widely used spectral detection equipment, and their optical structures mainly include: slits, collimating optical systems, gratings / prisms, collection optical systems, detectors / detector arrays; various types of lasers , there are semiconductor lasers, solid-state lasers, fiber lasers, etc.; and the laser output from the laser is mostly axisymmetric parallel light after various treatments and finally converges into a circular ...

AI Technical Summary

Problems solved by technology

Spectrum analyzers based on gratings / prisms are currently the most widely used spectral detection equipment, and their optical structures mainly include: slits, collimating optical systems, gratings / prisms, collection optical systems, detectors / detector arrays; there are many types of lasers , there are semiconductor lasers, solid-state lasers, fiber lasers, etc.; and the laser output from the laser is mostly axisymmetric parallel light after various treatments and finally converges into a circular spot. The energy of the excitation signal that is finally coupled into the spectrometer is limited. slit, such as figure 1 As shown, most of the energy is blocked by the slit and cannot enter the subsequent analysis system, which greatly reduces the collection efficiency of the system

[0003] In order to achieve higher efficiency, the usual practice is to strictly control the divergence angle of the laser, so that it can be converged at a very small divergence angle to achieve the smallest possible converging spot, which will lead to an increase in the manufacturing cost of the laser, and a very small converging spot. If the energy density is too high, it is easy to ignite the sample to be tested, and the small sampling range is not conducive to the measurement of mixed solids, and the focus depth of the system is small, and the system tolerance is small, etc.

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