High-aperture focusing through a spherical interface has been employed in optical data storage, photolithography, and especially microscopy. This paper first forms an approximate model, based on geometrical optics and Fourier optics, for evaluating focal fields of the focusing systems. This approximate model helps to clarify some doubts existing in literature. We then propose a rigorous model that is applicable to more general systems. Our model is based on multipole theory, which expands the electromagnetic fields into spherical harmonics.
© 2013 Optical Society of America
Original Manuscript: April 17, 2013
Revised Manuscript: May 30, 2013
Manuscript Accepted: May 31, 2013
Published: June 28, 2013
Vol. 8, Iss. 8 Virtual Journal for Biomedical Optics
Thanh Xuan Hoang, Xudong Chen, and Colin J. R. Sheppard, "Rigorous analytical modeling of high-aperture focusing through a spherical interface," J. Opt. Soc. Am. A 30, 1426-1440 (2013)