90-degree Raman signal collection planar light path system based on Dove prism

Abstract

The 90-degree Raman signal collection plane light path system based on the Dove prism comprises an excitation light path and a light scattering imaging light path, and the excitation light path is sequentially provided with a laser, a laser focusing lens and a sample pool. The light scattering imaging light path is sequentially provided with an achromatic collimating lens, an edge or notch filter, a Dove prism, an achromatic focusing lens, a spectrograph slit and a spectrograph; all the optical elements are located on the same plane, and a collimated light beam emitted by the laser is focused on a sample from one side of the sample pool after being converged by the laser focusing lens; the achromatic collimating lens is placed on the other side of the sample cell and forms a 90-degree angle with the incident direction of the laser to collect scattered signal light; laser Rayleigh lines are filtered out by an edge or notch filter, and Raman scattering signal light is introduced into a Dove prism; and a strip-shaped image is formed after being focused by the achromatic focusing lens, and the image and the slit of the spectrograph are enabled to parallelly coincide and enter the spectrograph by adjusting the Dove prism. The device has the characteristics of compact and stable structure and small optical signal loss.

Description

technical field [0001] The invention relates to the field of Raman detection of gas and liquid, in particular to a 90-degree Raman signal collection plane optical path system based on a Dove prism. Background technique [0002] Raman spectroscopy is one of the methods to study molecular structure, and can obtain various molecular information of substances. This method has obvious advantages in qualitative and quantitative identification of substances, and is widely used. In addition to the detection of solid samples, it is also applicable to the testing of gas and liquid samples. [0003] The signal collection of the Raman spectrometer system is mainly divided into two collection methods: 180° and 90°. The 180° method is more suitable for the collection optical path of micro-opaque sample signals, and is often used in confocal Raman microscopy. The 90-degree mode is suitable for the signal collection optical path of macroscopic samples, especially for transparent liquid or ...

AI Technical Summary

Problems solved by technology

However, to achieve this kind of long-distance laser penetration signal collection on the optical path requires that the laser penetration direction be parallel to the slit of the spectrometer, and for the spectrometer’s splitting optical path, the direction of the slit needs to be perpendicular to the incident surface of the grating, so pulling The excitation and collection optical path of the Mann signal and the spectroscopic optical path of the spectrometer are located in two mutually perpendicular planes, and the entire optical path system forms a spatial structure of two orthogonal planes, which is not conducive to the miniaturization of the instrument structure, and also affects the stability of the instrument. bring adverse effects

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