CN104730040A

CN104730040A - Portable laser induced spectrum detection system

Info

Publication number: CN104730040A
Application number: CN201310695255.XA
Authority: CN
Inventors: 王宏
Original assignee: Individual
Current assignee: Individual
Priority date: 2013-12-18
Filing date: 2013-12-18
Publication date: 2015-06-24

Abstract

The invention relates to a novel portable laser induced spectrum detection system, and belongs to the technical field of laser detection. The ultrashort pulse laser of subnanosecond laser makes the material surface produce a plasma spectrum with certain intensity, and then spectrum analysis is employed to obtain the material composition. The system is characterized by comprising an optical fiber coupling of subnanosecond pulse laser, a signal acquisition fiber, a C-T structure grating spectrometer, a data processing and display system and a battery module. The system can realize contact type measurement of solids and powder materials, such as metals, minerals and soils, and accurate detection of the content of more than 20 elements including iron, nickel, copper, magnesium, phosphorus, sulfur and carbon. The invention does not need any laser pulse trigger delay design, realizes real-time composition detection of all kinds of solid and powder through simple optical path and structure, and has the advantages of simple operation and fast measurement.

Description

A kind of portability induced with laser spectrum detection system

Technical field

The present invention relates to a kind of Novel portable induced with laser spectrum detection system, be applicable to carry out contact type measurement and analysis to the constituent content of the materials such as all kinds of solid such as metal, mineral, soil, powder, belong to technical field of laser detection.

Background technology

Induced with laser spectroscopic methodology (LIBS) is a kind of method of test sample composition, laser pulse is used to produce plasma at sample surfaces, it comprises the plasma mixture representing this sample element composition, is obtained the element composition of this sample by the spectrum of analysis plasma.Traditional LIBS technology, use high energy pulse or continuous wave laser, irradiation is carried out to sample surfaces and produces high-temperature plasma, in plasma spectrometry except comprising sample elemental characteristic spectral line, further comprises strong continuous spectrum (about tens nanoseconds).So traditional LIBS just needs in detection system, use integrated delay to avoid the impact of continuous spectrum, but because the kind measuring sample is different with form, the time that continuous spectrum continues is also different, and therefore traditional LIBS technology is often difficult to realize trace and accurate quantitative analyses owing to being subject to the impact of laser light scattering and continuous spectrum.

Summary of the invention

The object of the invention is to propose a kind of Novel portable induced with laser spectrum detection system, by adopting a kind of ultra-short pulse laser of subnanosecond of coupling fiber, material surface is made to produce the lower plasma spectrometry of temperature, thus effectively inhibit intensity continuum spectra, substantially increase the signal to noise ratio (S/N ratio) of whole LIBS system, no longer need detection system to carry out any integrated delay design, just can be realized the real-time examination and analysb of all kinds of solid matter composition by the light path of simple miniaturization and structure.This detection system comprises:

1. ultrashort pulse laser, its effect is by fiber guides, by pulse laser beam direct irradiation on sample surfaces, produces the plasma of some strength;

2. light splitting and detection system, by the fiber guides of coupling, directly guides to miniature light splitting light chamber system by the plasma spectrum of light source activation, and by ccd detector receiving spectrum information;

3. control and data processing and display module, its effect controls the firing time of laser pulse and the integral time of detection system, and analyze the spectral information of high s/n ratio and intensity, thus obtain the constituent content information of sample, and show;

4. power supply, for pulsed laser and miscellaneous part provide stable power supply;

5. by the optical fiber that above-mentioned parts couple together, system adopts fiber optic conduction, contact type measurement, irradiates and remains in certain distance with sample surfaces all the time with the optical fiber head received, thus realize the relatively-stationary spatial relationship of various piece.

In order to realize the target of portability, by the weight limits of complete machine below 2 kilograms, use outside miniature pulsed laser module, we also use the beam splitting system of miniaturization, and adopt the light splitting of C-T structured light, high performance Li ion battery is as power supply.In one embodiment, flat field grating can also be used as the core of miniature beam splitting system.Thus, according to the portability induced with laser spectrum detection system of said method design, comprise following components: subnanosecond pulse laser instrument, optical path (optical fiber), light splitting and detection (grating spectrograph), to control and data processing and display, battery module etc. (as Fig. 1).

Accompanying drawing illustrates:

Fig. 1 is the enforcement structure sketch map of portability LIBS system.

1. subnanosecond laser device; 2. micro spectrometer; 3. fiber guides system; 4. control and data processing and display module; 5. battery module.

Embodiment

By the ultrashort pulse subnanosecond laser device 1, repetition frequency 5KHz of microminiaturization, pulse width 1.5 nanosecond, pulse energy 40uJ, produces the plasma of some strength at material surface, thus obtains the spectral signal of high s/n ratio.The micro spectrometer 2 of C-T structure then achieves the analysis and treament of the high s/n ratio spectral signal to specific band.Fiber guides system 3, by coupling link laser instrument and spectrometer, simultaneously with contact type measurement sample surfaces, this ensures that there the relative uniformity of whole optical path, the plasma intensity of acquisition is stablized, and very little by the influence factor of ambient atmosphere.Control to process the result of spectral analysis with data processing and display module 4 and by display screen show sample constituent content intuitively.Battery module 5 uses high-performance Li ion battery, is the power supply that whole system is stable, and the general assembly (TW) of system lower than 2 kilograms, thus can realize real Handheld laser ultimate analysis.

Claims

1. a portability induced with laser spectrum detection system, comprises

Ultrashort pulse laser;

Light splitting and detection system;

Control and data processing and display module;

Power module; And

By the optical fiber that above-mentioned parts couple together.

2. a kind of portability induced with laser spectrum detection system as claimed in claim 1, it is characterized in that described ultrashort pulse laser uses the subnanosecond pulse laser instrument of high repetition frequency, its pulse width is 1-2 nanosecond, and repetition frequency is 5-10KHz, and individual pulse energy is 30-50uJ.

3. a kind of portability induced with laser spectrum detection system as claimed in claim 1 or 2, is characterized in that described ultrashort pulse laser and light splitting and detection system all adopt coupling fiber design.

4. a kind of portability induced with laser spectrum detection system described in claim 1 or 2, it is characterized in that described light splitting and detection system use miniature sub-ray spectrometer, its effective spectral coverage scope is 200-400nm, adopts C-T structure light splitting or the light splitting of flat field raster mode.