A miniature laser ablation nonaxial time-of-flight mass spectrometer for in situ elemental measurement of extraterrestrial planets

Abstract

To meet the requirements of in situ planetary surface analysis, this research designed a miniature laser ablation nonaxial time-of-flight (TOF) mass spectrometer, which enables qualitative and semi-quantitative analysis of the samples' elemental and isotopic compositions. To achieve high performance under a compact architecture, a compact non-axial configuration was designed and comprehensive integrated simulations of the mass analyzer were performed. Simulation results indicated that the system can achieve a mass resolution of 1025 (FWHM) and an ion transmission efficiency of 15.15% while maintaining a compact design with a volume of ϕ58 mm × 172 mm. Experimental verification has shown that the mass resolution of aluminum alloy samples can reach 300 (FWHM) and the dynamic range can be extended over five orders of magnitude. In the semi-quantitative analysis of the isotopic abundance ratios of different samples, the relative accuracy was within 5%. Leveraging the advantages of pulsed lasers, the system can complete up to 1000 single spectrum measurements per second, with a spatial resolution of 15 µm. In addition, the system does not require complex sample preparation and has the advantages of miniaturization, low power consumption, and rapid full-spectrum scanning, making it suitable for on-orbit elemental measurement and in situ measurement of extraterrestrial planets.