April 23, 2004 Ossining, NY -- RSoft Design Group, Inc. has released DiffractMOD, a new design tool for diffractive optical structures such as surface normal gratings, photonic bandgap crystals, and subwavelength periodic structures. It simulates electromagnetic wave diffraction from periodic structures.
DiffractMOD is well-suited to a variety of photonic applications including diffractive optical elements, narrow wavelength filters, DWDMs, polarization sensitive devices, optical interconnects, optical data storage, microlens arrays, and beam splitters and shapers. It can also be used in semiconductor manufacturing process for optical profilometry and nano-metrology.
DiffractMOD is based on the rigorous coupled wave analysis (RCWA) method and implements several advanced algorithms including a fast converging formulation of Maxwell equations and a numerical stabilization scheme. The RCWA method uses the concept of a unit cell to handle both 2D and 3D periodic structures and is specifically tailored for multilayer structures. The unit cell definition can have arbitrary geometry and the index distribution can consist of both standard dielectric materials and dispersive or lossy materials such as metals. The input or incident plane wave can have arbitrary direction and polarization. Various simulation results can be output including diffraction efficiency, each vectorial field component, and both near and far fields.
DiffractMOD also shares the same RSoft Photonic CAD Layout interface as the company's other component tools. The CAD interface allows the accurate definition of an arbitrary profile without limitations associated with a piecewise approximation. Optimized results can be found quickly as the design and modeling process is fully parameterized, which enables batch simulations.
A significant advantage of a shared CAD interface is that once designers create and analyze the diffractive structure in DiffractMOD, the same design layout can be directly simulated in the company's FullWAVE and BandSOLVE for other aspects of the same structure, such as time-domain response with finite-difference time domain method or band structure analysis with plane wave expansion method.
DiffractMOD can also be easily used with RSoft's BeamPROP, BandSOLVE, FullWAVE and GratingMOD for hybrid simulation of a multiple component module.