Laser dual-axis confocal Brillouin-Raman spectral measurement method and apparatus

Abstract

The invention relates to a laser dual-axis confocal Brillouin-Raman spectral measurement method and apparatus realizing integration of images and spectrums, belonging to the technical field of microscopic spectral imaging. According to the invention, dual-axis confocal microscopy and spectral detection technology are organically fused, Rayleigh light is used for assisted detection, Raman spectral detection technology and Brillouin spectral detection technology are cooperatively used to realize high spatial discrimination image-spectrum integrated detection of a system, and high spatial resolution is achieved. The apparatus has three modes, i.e., a three-dimensional chromatographic geometric imaging mode, a spectral detection mode and a micro-area image-spectrum chromatographic imaging mode, obtains basic properties and a plurality of crossing effects of substances by detecting abandoned Brillouin diffusion light in confocal Raman spectral detection, realizes acquisition of a plurality of parameters like the micro-area morphology, state, texture and attributes of a measured sample in virtue of the characteristic that advantages of confocal Raman spectral detection technology and confocal Brillouin spectral detection technology are complementary, and has wide application prospects in fields like biomedicine, high energy manufacturing and material chemistry.

Description

technical field [0001] The invention belongs to the technical field of micro-spectral imaging, combines biaxial confocal microscopic technology and spectral detection technology, and relates to a laser biaxial confocal Brillouin-Raman spectral measurement method and device of "map-spectrum integration", which can be used Multi-parameter comprehensive testing and high-resolution imaging of mechanical morphology properties of samples. technical background [0002] When light passes through the medium, the medium particles are affected by the light wave, transition from one quantum state to another quantum state, and radiate scattered waves at the same time. Different energy level transitions produce Rayleigh scattering and anti-Stokes scattering respectively. According to the degree of change with the wavelength of the incident light, light scattering is divided into: Rayleigh scattering (Rayleigh), Raman scattering (Raman) and Brillouin scattering (Brillouin). [0003] In Ra...

AI Technical Summary

Problems solved by technology

[0010] (1) The spatial resolution is not high, only about 1 μm

The intensity signal of the Raman spectrum excited by the laser is very weak, which is about 6 orders of magnitude lower than the intensity of the abandoned sharp beam. Therefore, in order to detect the extremely weak Raman signal, the aperture of the pinhole of the confocal Raman spectroscopy detection system is usually exist It is about 10 μm larger than the pinhole aperture value of the existing confocal microscope. As a result, the spatial resolution of the existing confocal Raman spectroscopy is only 1 μm, and it has been more than 20 years since the invention of the confocal Raman spectroscopy detection technology. has not fundamentally changed

[0011] (2) Poor ability to capture the Raman spectrum excited by the focal point

Confocal Raman spectroscopy detection system, due to the insensitive intensity response at the extreme point, it is difficult to capture the Raman spectrum information of the sample excited at the focal point, thus limiting the spatial resolution of the existing confocal Raman spectroscopy detection ability;

[0012] (3) Long detection time and large system drift

Because the confocal Raman spectrum signal is very weak, the detector needs to be integrated for a long time (often several hours) when performing spectral imaging. The drift of the optical system and the sample worktable often causes the sample to defocus, which in turn reduces the confocal Raman. Spatial resolution of spectral detection;

[0013] (4) The stray light of the sample is strong, which affects the signal-to-noise ratio of the Raman spectroscopy detection instrument

The existing confocal Raman spectroscopic detection instrument adopts the back reflection sample detection method and the incident excitation optical path and the scattered light detection optical path are completely in the same optical path, which is bound to have the problem of large stray light interference of the sample, which limits the existing Spectral detection capability of confocal microscopes for highly scattering samples;

[0014] (5) The ability to measure multiple performance parameters needs to be improved urgently

[0015] Usually the intensity of the Raman spectrum scattered by the sample is 10 times the intensity of the reflected Rayleigh beam. -3 ~10 -6 times, while the existing confocal Raman spectroscopy detection instruments all detect the weak Raman spectrum scattered by the sample and discard the Rayleigh beam and Brillouin beam which are stronger than the Raman scattered light

Images