Optical fiber sensing-based laser excitation heat wave signal detection device

Abstract

The invention provides an optical fiber sensing-based laser excitation heat wave signal detection device, comprising a pumping laser light source, a detection laser light source, a focusing lens and optical fiber. The optical fiber is used to transmit a pumping laser beam and a detection laser light beam, the same focusing lens is used to converge the two beams, and the detection laser light beam reflected or transmitted by a sample is received by also using the optical fiber at a detection end, so that the structure of a whole light path system is greatly simplified, instrument microminiaturization and portability can be realized, instrument cost is greatly reduced, and the popularization and application of a laser excitation heat wave signal detection technology are facilitated.

Description

Technical field [0001] The invention relates to the technical field of laser-excited heat wave detection, in particular to a laser-excited heat wave signal detection device based on optical fiber sensing. Background technique [0002] Laser-induced thermal wave technology is an effective detection method with high sensitivity, non-contact, and diverse measurement methods. It can be used for detection and analysis of different material properties (including material absorption characteristics, thermophysical characteristics, defects, etc.). A common detection method for detecting the laser-excited heat wave signal is: when the pump laser interacts with the material and is excited to generate the heat wave signal, a weaker detection laser is also used to pass the heat wave signal in the material. Area, the detection laser beam can have a certain angle with the pump laser beam, or it can be coaxial. [0003] When the detection laser is excited by the pump laser to generate the therm...

AI Technical Summary

Problems solved by technology

[0005] The purpose of the present invention is to provide a laser-excited thermal wave signal detection device based on optical fiber sensing, which uses the characteristics of the optical fiber itself to have a small core diameter and spatial filtering capability, and at the same time combines the chromatic aberration characteristics of the optical focusing lens to realize laser detection. Stimulate the detection of thermal wave signals, thereby greatly simplifying the structure of the entire detection device, which can solve the problems of cumbersome, bulky, expensive, and unfavorable for carrying and transportation in current photothermal detection devices

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