Study of 18.2 nm Schwarzschild microscope for plasma diagnostics

摘要

A Schwarzschild microscope at 18.2 nm for ultra-fast laser plasma diagnostics has been developed. Based on the third-order aberration the microscope is designed for numerical aperture of 0.1 and magnification of 10. Spatial resolution of the objective can achieve 1250 lp/mm within the field of ±1 mm. Mo/Si multilayer films with peak throughout at 18.2 nm is designed and deposited by magnetron sputtering, and the measured reflectivity of optical elements is 45%. The 600 lp/inch copper grid backlit by laser produced plasma is imaging via Schwarzschild microscope on CCD. The spatial resolution is measured as 3 |im approximately in the field of 1.2 mm.