MEMS-based portable confocal Raman spectroscopy rapid imaging system.

Aiming at the miniaturization and rapid imaging requirements of a portable confocal Raman system, a MEMS-based portable confocal Raman spectroscopy rapid imaging method is proposed in this study. This method combines the dual 2D MEMS mirror scanning method and the grid-by-grid scanning method. The dual 2D MEMS mirror scanning method is used for the miniaturization design of the system, and the grid-by-grid scanning method is used for rapid imaging of Raman spectroscopy. Finally, the rapid imaging and miniaturization design of a portable confocal Raman spectroscopy system are realized. Based on this method, a portable confocal Raman spectroscopy rapid imaging system with an optical probe size of just 98m m×70m m×40m m is constructed. The experimental results show that the imaging speed of the system is 45 times higher than that of the traditional point-scan confocal Raman system, and the imaging speed can be further improved according to the requirements. In addition, the system is used to swiftly identify agate ore, and the material composition distribution image over a 126µm 2×126µm 2 region is obtained in just 16 min. This method provides a new solution for the rapid imaging and miniaturization design of the confocal Raman system, as well as a new technical means for rapid detection in deep space exploration, geological exploration, and field detection.

Laser confocal vibration measurement method with high dynamic range.

A new laser confocal vibration measurement method (LCVM) is proposed to meet the requirements of high precision and high dynamic range measurements in micro and nano electromechanical systems. The proposed method uses different measurement modes to ensure that the amplitude solution interval of the out-of-plane is always in the optimal test interval of a confocal curve with the highest sensitivity to axial displacement, and thereby achieving the high-precision extraction of large-scale frequency and the high-precision measurement of large-scale amplitude. Using a 100×, NA=0.9 objective lens with a working distance of 1 mm, the theoretical analysis and preliminary experimental results indicate that the maximum measurable amplitude is 500 µm, the displacement resolution of the amplitude is 4 nm, and the measurable frequency range limited by electrical design is 0-120 MHz. The LCVM provides a novel approach for out-of-plane vibration measurements.