Nonlinear micro imaging method of multiphoton ionization induced by ultrashort pulse laser

Abstract

The invention relates to an ultrashort-pulse laser-induced multi-photon ionization nonlinear microscopic imaging method and system and application thereof. The converging ultrashort pulse laser is used to induce the ionization of the gas on the local surface of the measured object or the small area inside the measured object to form a micro-area plasma. The photodetector is used to detect the electromagnetic wave radiation intensity of the plasma in the visible light band, and is recorded by recording The plasma radiation intensity at different positions of the measured object is used to obtain a microscopic image reflecting the spatial variation of the material properties of the measured object. This method has high detection sensitivity, and the identification rate of small changes in material components is much higher than that of linear imaging microscopes; it has micron or submicron spatial resolution, which can reach or exceed the diffraction limit; the degree of damage to the measured object is low, It can be used for surface detection of various materials such as metals, semiconductors, ceramics, etc. It can also be used for the detection of the surface and internal structure of transparent materials, and it can also be used for precise diagnosis of biological, human and animal diseased tissues.

Description

【Technical field】 [0001] The invention relates to the technical field of material analysis and microscopic imaging, in particular to a new method and system of nonlinear microscopic imaging based on the multi-photon ionization process of atoms and molecules and its application. 【Background technique】 [0002] In the development of science and technology in the human world, microscopic imaging of microscopic objects and microscopic material analysis have always been an extremely important scientific research field, and breakthroughs in this field often have a significant role in promoting the development of other disciplines and technologies. From the earliest optical magnifying glass to modern super microscopes, such as scanning electron microscopes, atomic force microscopes and tunneling scanning microscopes, it can be said that the emergence of every new imaging technology is an important milestone in the development of science and technology. With the emergence of lasers ...

AI Technical Summary

Problems solved by technology

However, LIBS needs to use a relatively complex spectral analysis system, so it is often accompanied by problems such as insufficient utilization of the overall optical signal, large amount of test data, and long time

In addition, when the sensitivity of the spectral analysis system cannot meet the requirements, it is necessary to increase the intensity of the plasma signal by increasing the intensity of the irradiated laser, which increases the degree and scope of damage to the measured object, and serious damage will also cause causing a decrease in spatial resolution

Therefore, the application of LIBS has great limitations in microscopic imaging and material analysis in micro-regions on the micron or sub-micron scale.

Images