CN214844827U - 90-degree Raman signal collection plane optical path system based on dove prism - Google Patents

Abstract

A90-degree Raman signal collection plane optical path system based on a dove prism comprises an excitation optical path and a light scattering imaging optical path, wherein the excitation optical path is sequentially provided with a laser, a laser focusing lens and a sample cell, and the light scattering imaging optical path is sequentially provided with an achromatic collimating lens, an edge or notch filter, the dove prism, the achromatic focusing lens, a spectrometer slit and a spectrometer; all the optical elements are positioned on the same plane, and collimated light beams emitted by the laser are focused on a sample from one side of the sample cell after being converged by the laser focusing lens; the other side of the achromatic collimating lens sample cell forms a 90-degree angle with the laser incidence direction to collect scattered signal light; the edge or the notch filter filters out laser Rayleigh lines in the Raman scattering signal light, and the Raman scattering signal light is introduced into the dove prism; and focusing the image by an achromatic focusing lens to form a strip-shaped image, and enabling the image and the slit of the spectrometer to be overlapped in parallel to enter the spectrometer by adjusting the dove prism. The optical fiber coupler has the characteristics of compact and stable structure and small optical signal loss.

Description

90-degree Raman signal collection plane optical path system based on dove prism

Technical Field

The utility model relates to a raman of gas, liquid detects the field, especially relates to a 90 degrees raman signal collection plane light path systems based on dove prism.

Background

The Raman spectrum technology is one of methods for researching molecular structures, can obtain various molecular information of substances, has obvious advantages in qualitative and quantitative identification of the substances and the like, and is very wide in application. Besides the detection of solid samples, the method is also applicable to the detection of gas and liquid samples.

The signal collection of the Raman spectrometer system mainly comprises two collection modes of 180 degrees and 90 degrees, wherein the 180 degree mode is more suitable for a collection light path of a micro-region light-tight sample signal and is commonly used for confocal microscopy. The 90 degree approach is suitable for use in signal collection optical paths for macroscopic samples, particularly for transparent liquid or gas samples. The device can collect signals with longer laser penetration distance, so that the device has higher detection sensitivity. However, the signal collection of the long-distance laser penetration on the light path requires that the penetration direction of the laser is parallel to the slit of the spectrometer, and for the light splitting path of the spectrometer, the direction of the slit needs to be perpendicular to the incident surface of the grating, so the excitation and collection light path of the raman signal and the light splitting path of the spectrometer are respectively in two mutually perpendicular planes, and the whole light path system forms a spatial structure of two orthogonal planes, which is not beneficial to the miniaturization of the instrument structure and brings adverse effects on the stability of the instrument.

Disclosure of Invention

An object of the utility model is to solve the above-mentioned problem among the prior art, provide a 90 degrees raman signal collection plane optical path systems based on dove prism, through introducing the dove prism that can rotate the image in the light scattering imaging light path, realize collecting more raman scattering light from the vertical direction, be applicable to the design of the miniaturized portable raman spectroscopy of high detection sensitivity.

In order to achieve the above purpose, the utility model adopts the following technical scheme:

a90-degree Raman signal collection plane optical path system based on a dove prism comprises an excitation optical path and a light scattering imaging optical path which are arranged at 90 degrees, wherein a laser, a laser focusing lens and a sample cell are sequentially arranged on the excitation optical path, and an achromatic collimating lens, an edge or notch filter, the dove prism, the achromatic focusing lens, a spectrometer slit and a spectrometer are sequentially arranged on the light scattering imaging optical path; all optical elements of the light path are positioned in the same plane, the laser emits collimated light beams, and the light beams are focused on a sample from one side of the sample cell after being converged by the laser focusing lens; the other side of the achromatic collimating lens sample cell forms a 90-degree angle with the laser incidence direction to collect scattered signal light; the edge or the notch filter filters out laser Rayleigh lines in the Raman scattering signal light, and the Raman scattering signal light is introduced into the dove prism; and focusing the image by an achromatic focusing lens to form a strip-shaped image, and enabling the image and the slit of the spectrometer to be overlapped in parallel to enter the spectrometer by adjusting the dove prism.

The dove prism enables the image to rotate 90 degrees around the optical axis, and the superposition of the Raman scattering signal light image and the slit of the spectrometer is achieved in a two-dimensional plane light path.

The dove prism is placed at a 45 degree rotation and allows fine tuning to achieve parallel registration of the scattered signal light image with the spectrometer slit.

The sample cell has at least two mutually perpendicular optical window sides, and laser is incident from one side and raman scattering signal light is collected at the other 90-degree side.

Compared with the prior art, the utility model discloses technical scheme obtains beneficial effect is:

1. the utility model discloses an introduce the dove prism that can rotate the image in the scattered light collection imaging light path, realize the bar image of scattered signal light and the parallel coincidence of spectrum appearance slit and adjust to can obtain the collection of the extremely high 90 degrees raman scattering signal light of light throughput in the light path system of a two-dimensional plane.

2. Compare in the optical path system of other 90 degrees collection raman scattering light, the utility model discloses a light path is simple, and compact structure and stability, optical signal loss are little, and optical element in the light path all keeps on same two-dimensional horizontal plane, vertically reduces the shared space of system, and this light path has fine application prospect in miniaturized portable raman spectroscopy.

3. The utility model discloses but wide application in the raman detection of gas, liquid, laser is from sample cell one side incidence, collects the raman scattered light from sample cell vertically opposite side, and scattered light bar image and spectrum appearance slit coincidence increase the optical path that laser arouses the sample, and more sample molecules are aroused by laser, enlarge the total scattering cross-section of sample molecule effectively, obtain more raman scattered light signal from this.

Drawings

Fig. 1 is a schematic structural diagram of the present invention.

Reference numerals: the device comprises a laser 1, a laser focusing lens 2, a sample cell 3, an achromatic collimating lens 4, an edge or notch filter 5, a dove prism 6, an achromatic focusing lens 7, a spectrometer slit 8 and a spectrometer 9.

Detailed Description

In order to make the technical problem, technical solution and beneficial effects to be solved by the present invention clearer and more obvious, the following description is made in detail with reference to the accompanying drawings and embodiments.

As shown in fig. 1, the present embodiment includes an excitation optical path and a light scattering imaging optical path, the excitation optical path and the light scattering imaging optical path are at 90 degrees, all optical elements of the optical paths are in the same plane, and specifically, the present embodiment includes the following components:

a laser 1 capable of outputting a light source for exciting a Raman signal of a sample;

a sample cell 3, at least two mutually perpendicular sides of which are transparent;

a laser focusing lens 2 for focusing laser light into the sample cell 3;

an achromatic collimating lens 4 for collecting the Raman signal light emitted from the side of the sample cell 3 and forming a collimated beam;

an edge or notch filter 5 for filtering out the laser rayleigh lines;

a dove prism 6 placed in the collimated light beam of the signal light and rotated by 45 degrees around the optical axis to rotate the image of the signal light by 90 degrees;

an achromatic focusing lens 7 for focusing the signal light and introducing it into a spectrometer slit 8;

and a spectrometer 9 for splitting and recording the signal light and converting the signal light into an electronic digital signal to obtain a Raman spectrogram.

In this embodiment, the dove prism 6 is placed at an angle of 45 degrees of rotation and fine adjustment is allowed to realize parallel coincidence of the scattered signal light image and the spectrometer slit 8; the sample cell 3 has at least two mutually perpendicular optical window sides, laser light is incident from one side, and Raman scattering signal light is collected at the other 90-degree side.

The working principle of the utility model is as follows:

collimated light beams emitted by a laser 1 are focused into a sample cell 3 through a laser focusing lens 2, and a sample is excited to generate Raman scattered light; the achromatic collimating lens 4 collects and collimates scattered light from the other side of the sample cell 3 at 90 degrees to the laser incidence direction, and after the laser rayleigh lines in the scattered signal light are filtered by the edge or notch filter 5, the collimated raman signal light beam is introduced into the dove prism 6. Because the dove prism 6 rotates 45 degrees around the optical axis, the signal light strip-shaped image on the focal plane of the achromatic focusing lens 7 rotates 90 degrees around the optical axis, the signal light strip-shaped image is vertically converted from horizontal to parallel to the slit 8 of the spectrograph, and the spectrograph 9 performs light splitting photoelectric signal conversion on the signal light and outputs a spectrum spectrogram.

The utility model discloses introduce the dove prism that can rotate the image in the light scattering imaging light path, when realizing that the light path keeps on same two-dimensional horizontal plane, the bar type image and the slit coincidence of scattered light, the spectrum appearance obtains the shared space of more raman scattered light signal greatly dwindle simultaneously from this, more is applicable to the high demand of miniaturized portable raman spectrum appearance to signal luminous flux.

Claims (3)

1. A90-degree Raman signal collection plane optical path system based on dove prism is characterized in that: the laser spectrometer comprises an excitation light path and a light scattering imaging light path which are arranged at 90 degrees, wherein a laser, a laser focusing lens and a sample cell are sequentially arranged on the excitation light path, and an achromatic collimating lens, an edge or notch filter, a dove prism, an achromatic focusing lens, a spectrometer slit and a spectrometer are sequentially arranged on the light scattering imaging light path; all optical elements of the optical path are in the same plane; the laser is used for outputting a light source for exciting a Raman signal of the sample; the laser focusing lens is used for focusing laser into the sample cell; the achromatic collimating lens is used for collecting the Raman signal light transmitted from the side surface of the sample cell and forming a collimated light beam; the edge or notch filter is used for filtering laser Rayleigh lines; the dove prism is arranged in the signal light collimated light beam to enable the signal light image to rotate 90 degrees around the optical axis; the achromatic focusing lens is used for focusing the signal light and introducing the signal light into a slit of a spectrometer; the spectrometer is used for splitting and recording the signal light and converting the signal light into an electronic digital signal to obtain a Raman spectrogram.

2. The dove prism-based 90-degree raman signal collection planar optical path system of claim 1, wherein: the dove prism is placed at a 45 degree rotation and allows fine tuning to achieve parallel registration of the scattered signal light image with the spectrometer slit.

3. The dove prism-based 90-degree raman signal collection planar optical path system of claim 1, wherein: the sample cell has at least two mutually perpendicular optical window sides, and laser is incident from one side and raman scattering signal light is collected at the other 90-degree side.

Images