CN103994973A - Raman spectrum detection head and detection method - Google Patents

Abstract

The invention provides a Raman spectrum detection head and a detection method, including: a light shield, the light shield includes a slit and a detection mirror, the slit is used to let the Raman scattered light emit to the sample, and let the signal light generated on the surface of the sample emit In, the detection mirror is used to emit signal light; the hood also includes: laser line light source, used to emit linear laser light; filter filter, used to filter Rayleigh scattered light in the linear laser, and the remaining Raman scattered light ; The beam splitting filter is used to reflect the Raman scattered light to the scanning mirror, and the signal light reflected back by the scanning mirror is emitted through the detection mirror; the scanning mirror, the scanning mirror is reflected through the beam splitting filter by reciprocating vibration Reflected Raman scattered light, in order to obtain uniform linear Raman scattered light, make it exit to the sample surface through the slit, and reflect the signal light of Raman detection generated by the sample surface incident through the slit to the beam splitter filter. The invention can perform fast moving detection and signal collection on samples.

Description

A Raman spectrum detection head and detection method

technical field

The invention relates to the field of optical detection, in particular to a Raman spectrum detection head and a detection method.

Background technique

Raman scattering is the scattering of frequency changes caused by the interaction between incident light and molecular motion when light passes through a medium. Raman spectroscopy is often used to characterize the structural characteristics of molecules, also known as the "fingerprint" of molecules. The analysis methods of Raman spectroscopy mainly include techniques such as Fourier transform, high temperature, resonance, surface enhancement, confocal microscopy, and solid-state photoacoustics. Raman spectroscopy has a wide range of applications in many fields, especially it can provide fast, simple, non-destructive, repeatable qualitative and quantitative analysis techniques, without cumbersome pretreatment steps, avoiding damage to samples, and achieving screening speed Speed up. Of course, Raman technology also has some shortcomings, such as the peaks are easy to overlap, and it is easy to be affected by factors such as instrument parameters. When measuring fluorescent substances, there will be fluorescence interference, and the Raman effect is too weak, about 10-6 times. Although the rapid development of nanotechnology provides a new direction for Raman spectroscopy detection, the limitation of using nanotechnology to enhance the weak Raman signal remains to be further studied.

In the prior art, Raman technology can only be used for point spectrum detection. Since the Raman signal is relatively weak and the fluorescence background signal is relatively strong, although Raman spectroscopy has great advantages in identifying the chemical bonds of substances, it is often due to The detection limit cannot reach the standard method, that is, the minimum content detection limit determined by gas spectrometry and liquid spectrometry, resulting in obvious deficiencies and disadvantages in quantitative analysis. Moreover, the detection device of Raman spectroscopy is relatively complicated, has high requirements on the optical path, and is not easy to move, which has caused certain obstacles to the practical application of Raman detection.

Contents of the invention

(1) Technical problems to be solved

The invention provides a Raman spectrum detection head and a detection method to solve the technical problem in the prior art that the Raman technology can only perform point spectrum detection and the detection device is not easy to move.

(2) Technical solutions

In order to solve the above technical problems, the present invention provides a Raman spectroscopy detection head, comprising: a shading cover, the shading cover includes a slit and a detection mirror, the slit is used to let the Raman scattered light exit to the sample, and make the The signal light generated on the surface of the sample is incident, and the detection mirror is used to emit the signal light;

The hood also includes:

Laser line light source, used to emit line laser;

filter filter, used to filter the Rayleigh scattered light in the linear laser, and the remaining Raman scattered light;

A beam splitting filter, used to reflect the Raman scattered light passing through the filter filter to the scanning mirror, and make the signal light reflected back by the scanning mirror exit through the detection mirror;

A scanning mirror, the scanning mirror reflects the Raman scattered light reflected by the beam splitting filter by reciprocating vibration, so as to obtain uniform linear Raman scattered light, which is emitted to the sample surface through the slit , and reflect the Raman detection signal light generated on the sample surface incident through the slit to the beam splitting filter.

Further, between the laser line light source and the filter filter also includes:

The collimating lens is used for collimating and converging the linear laser light emitted by the laser line light source into uniform parallel light.

Further, the laser line light source is:

785nm laser line light source, maximum output power 5w, maximum output 1mm×20cm long laser line.

further,

The laser line light source includes a plurality of laser point light sources arranged in a row.

further,

The laser line light source includes 9 laser point light sources arranged in a row.

further,

The laser line light source, collimating lens, filtering filter and beam splitting filter are sequentially distributed on a straight line;

The scanning mirror, the beam splitting filter and the detecting mirror are sequentially distributed on another straight line perpendicular to the straight line;

The scanning mirror and the beam splitting filter are parallel to each other and form an angle of 45 degrees with the two straight lines respectively.

Further, the hood also includes:

Handle for moving and carrying the detection head.

On the other hand, the present invention also provides a Raman spectrum detection method, using the Raman spectrum detection head as described in any one of the above to perform Raman spectrum detection, including:

Emit a linear laser through a laser line light source;

Using a filter filter to filter the Rayleigh scattered light in the linear laser, and the remaining Raman scattered light;

The filtered Raman scattered light is reflected to the scanning mirror by a beam splitting filter;

Using the scanning mirror to reflect the Raman scattered light by reciprocating vibration to obtain uniform linear Raman scattered light, and emit the uniform linear Raman scattered light to the sample surface through the slit of the light shield;

Let the uniform linear Raman scattered light irradiate on the surface of the sample, and the signal light of Raman detection generated by the Raman detection enters the scanning mirror through the slit, and the signal light is reflected by the scanning mirror, passes through the beam splitting filter, and then passes through the detection on the light shield. mirror out.

(3) Beneficial effects

It can be seen that in the Raman spectrum detection head and detection method provided by the present invention, the laser line light source, filter filter, beam splitting filter and scanning mirror are integrated in the hood of the Raman spectrum detection head, providing a A portable, integrated Raman spectroscopy detection head that enables rapid mobile detection and signal acquisition of samples. Moreover, the present invention detects the sample by using a linear laser, which solves the technical problem that only point spectrum detection can be performed in the prior art Raman detection technology, and has high application value.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description These are some embodiments of the present invention. Those skilled in the art can also obtain other drawings based on these drawings without creative work.

1 is a schematic diagram of the basic structure of a Raman spectrum detection head according to an embodiment of the present invention;

2 is a schematic diagram of a preferred structure of a Raman spectrum detection head according to an embodiment of the present invention;

Fig. 3 is a schematic flow chart of a Raman spectroscopy detection method according to an embodiment of the present invention.

Detailed ways

In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments It is a part of embodiments of the present invention, but not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without creative efforts fall within the protection scope of the present invention.

The embodiment of the present invention firstly provides a Raman spectrum detection head, referring to FIG. 1 , including: a light shield 1, the light shield 1 includes a slit 2 and a detection mirror 3, and the slit 2 is used to let the Raman scattered light exit to the sample 4 , and the signal light generated on the surface of the sample 4 is incident, and the detection mirror 3 is used to emit the signal light;

The hood 1 also includes:

Laser line light source 5, used to emit line laser;

filter filter 6, used to filter the Rayleigh scattered light in the linear laser, and the remaining Raman scattered light;

The beam splitting filter 7 is used to reflect the Raman scattered light passing through the filter filter 6 to the scanning mirror 8, and make the signal light reflected by the scanning mirror 8 exit through the detection mirror 3;

The scanning mirror 8, the scanning mirror 8 reflects the Raman scattered light reflected by the beam splitting filter 7 by reciprocating vibration, so as to obtain uniform linear Raman scattered light, so that it is emitted to the surface of the sample 4 through the slit 2, And reflect the Raman detection signal light generated on the surface of the sample 4 incident through the slit 2 to the beam splitting filter 7 .

In order to obtain a more uniform linear laser, preferably, between the laser line light source 5 and the filter filter 6, a collimating lens 9, as shown in FIG. Converge straight into a uniform parallel light.

Preferably, the laser line light source 5 can be: a 785nm laser line light source with a maximum output power of 5w, and the laser outputs a laser line with a length of 1mm (MAX)×20cm.

Preferably, the laser line light source 5 can be excited and converged into a line light source by a plurality of laser point light sources arranged in a row, wherein the number of laser point light sources can be nine.

Preferably, as shown in Figure 2, the laser line light source 5, the collimating lens 9, the filter filter 6 and the beam splitting filter 7 can be distributed on a straight line in turn; and the scanning mirror 8, the beam splitting filter 7 And the detection mirror 3 can be distributed in turn on another straight line perpendicular to the above straight line; wherein the scanning mirror 8 and the beam splitting filter 7 are parallel to each other and form an angle of 45 degrees with the two straight lines respectively. Moreover, since the Raman scattered light reflected by the scanning mirror 8 needs to exit on the sample 4 through the slit 2, the signal light on the surface of the sample 4 also needs to be incident on the scanning mirror 8 through the slit 2. Therefore, the scanning mirror 8, the slit 2 and sample 4 are also sequentially distributed on a straight line, and the scanning mirror 8 vibrates cyclically around a 45-degree angle with the straight line.

In order to make the Raman spectrum detection head in the embodiment of the present invention easy to carry and move, preferably, the light shield 1 can also include a handle, so that the integrated Raman spectrum detection head can be used for fast mobile detection of samples in different occasions and signal acquisition.

Wherein, when the Raman spectroscopy detection head in the embodiment of the present invention detects a sample, the sample 4 can be placed on a two-dimensional translational sample stage, so as to perform two-dimensional laser line scanning on the entire surface of the sample 4 by moving the sample 4 in the two-dimensional direction , to obtain the spectrum information of the entire sample surface, and obtain more comprehensive and accurate Raman spectrum detection data.

The embodiment of the present invention also provides a Raman spectrum detection method, using the Raman spectrum detection head in the embodiment of the present invention to perform Raman spectrum detection, as shown in Figure 3, the specific steps include:

Step 301: emit a linear laser through a laser line light source;

Step 302: Using a filter filter to filter the Rayleigh scattered light in the linear laser, leaving the remaining Raman scattered light;

Step 303: Reflect the filtered Raman scattered light to the scanning mirror by using a beam splitting filter;

Step 304: using the scanning mirror to reflect the Raman scattered light by reciprocating vibration to obtain uniform linear Raman scattered light, and emit the uniform linear Raman scattered light to the sample surface through the slit of the light shield;

Step 305: irradiating the uniform linear Raman scattered light on the surface of the sample, the signal light of Raman detection generated by the Raman detection is incident on the scanning mirror through the slit, and the signal light is reflected by the scanning mirror, passes through the beam splitting filter, and then passes through the hood The detection mirror on the exit.

It can be seen that the embodiments of the present invention have at least the following beneficial effects:

In the Raman spectroscopy detection head and detection method provided in the embodiments of the present invention, the laser line light source, filter filter, beam splitting filter and scanning mirror are integrated in the hood of the Raman spectroscopy detection head, providing a A portable, integrated Raman spectroscopy detection head that enables rapid mobile detection and signal acquisition of samples. Moreover, the embodiment of the present invention detects the sample by using a linear laser, which solves the technical problem that only point spectrum detection can be performed in the prior art Raman detection technology, and has high application value.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: it can still be Modifications are made to the technical solutions described in the foregoing embodiments, or equivalent replacements are made to some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims (8)

1. A Raman spectrum detection head, it is characterized in that, comprises: light shield, described light shield comprises slit and detection mirror, and described slit is used for making Raman scattered light go out to sample, and makes described sample The signal light generated on the surface is incident, and the detection mirror is used to emit the signal light; The hood also includes: Laser line light source, used to emit line laser; filter filter, used to filter the Rayleigh scattered light in the linear laser, and the remaining Raman scattered light; A beam splitting filter, used to reflect the Raman scattered light passing through the filter filter to the scanning mirror, and make the signal light reflected back by the scanning mirror exit through the detection mirror; A scanning mirror, the scanning mirror reflects the Raman scattered light reflected by the beam splitting filter by reciprocating vibration, so as to obtain uniform linear Raman scattered light, which is emitted to the sample surface through the slit , and reflect the Raman detection signal light generated on the sample surface incident through the slit to the beam splitting filter. 2. Raman spectrum detection head according to claim 1, is characterized in that, also comprises between described laser line light source and described filtering filter: The collimating lens is used for collimating and converging the linear laser light emitted by the laser line light source into uniform parallel light. 3. The Raman spectroscopy detection head according to claim 1, wherein the laser line light source is: 785nm laser line light source, maximum output power 5w, maximum output 1mm×20cm long laser line. 4. Raman spectrum detection head according to claim 1, is characterized in that: The laser line light source includes a plurality of laser point light sources arranged in a row. 5. Raman spectrum detection head according to claim 4, is characterized in that: The laser line light source includes 9 laser point light sources arranged in a row. 6. The Raman spectroscopy detection head according to claim 2, characterized in that: The laser line light source, collimating lens, filtering filter and beam splitting filter are sequentially distributed on a straight line; The scanning mirror, the beam splitting filter and the detecting mirror are sequentially distributed on another straight line perpendicular to the straight line; The scanning mirror and the beam splitting filter are parallel to each other and form an angle of 45 degrees with the two straight lines respectively. 7. The Raman spectroscopy detection head according to any one of claims 1 to 6, wherein the light shield further comprises: Handle for moving and carrying the detection head. 8. A Raman spectrum detection method, is characterized in that, utilizes the Raman spectrum detection head as described in any one in claim 1 to 7 to carry out Raman spectrum detection, comprising: Emit a linear laser through a laser line light source; Using a filter filter to filter the Rayleigh scattered light in the linear laser, and the remaining Raman scattered light; The filtered Raman scattered light is reflected to the scanning mirror by a beam splitting filter; Using the scanning mirror to reflect the Raman scattered light by reciprocating vibration to obtain uniform linear Raman scattered light, and emit the uniform linear Raman scattered light to the sample surface through the slit of the light shield; Let the uniform linear Raman scattered light irradiate on the surface of the sample, and the signal light of Raman detection generated by the Raman detection enters the scanning mirror through the slit, and the signal light is reflected by the scanning mirror, passes through the beam splitting filter, and then passes through the detection on the light shield. mirror out.