Various rigorous methods have been developed for the efficient analysis of diffractive optical elements (DOEs). We apply a gradient algorithm of synthesis to design two-dimensional DOEs, with the diffraction of the electromagnetic wave of TE polarization using a hybrid finite element - boundary element method. The hybrid method is capable of modeling inhomogeneous DOEs in unbounded free space in a computationally efficient manner. In this paper we discuss the application of the gradient optimization method to the matrix notation of the hybrid method. Such an application makes it possible to analyze DOE profiles with a large number of features. This allows one to overcome the limitations of calculation time dependent on the amount of the DOE modifications. We use the gradient method to design binary-phase lenses with subwavelength features. Although we have considered only binary-phase lenses, the gradient method presented is also suitable for designing continuous-relief DOEs.

Date Published: 21 December 2001
PDF: 8 pages
Proc. SPIE 4436, Wave-Optical Systems Engineering, (21 December 2001); doi: 10.1117/12.451297

Published in SPIE Proceedings Vol. 4436:
Wave-Optical Systems Engineering
Frank Wyrowski, Editor(s)