Rigorous Modeling of Sensor Responses in Confocal Microscopy Using the 3D Boundary Element Method

To accurately predict the optical sensor response in confocal microscopy, we develop a digital twin of the system using the rigorous 3D boundary element method (BEM). This approach allows us to analyze and correct measurement errors arising from surfaces with varying shapes, slopes, and pitches. We systematically simulate a range of structures, including rectangular gratings and rough surfaces with varying roughness, and validate the results against experimental data. Additionally, simulations of gratings with edge rounding and substrate tilt provide valuable insights into experimentally observed phenomena.