Most computer modeling methods for diffraction structures suffer from at least one of
the following problems:
- Excessive computational requirements
- Restrictions to certain geometrical configurations (such as rectangular shaped
structures)
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The Surface Impedence Method, as described by Hessel and Oliner*, overcomes these
problems. By finding the wave impedence at the surface of the structure, Zs,
one has essentially solved the diffraction problem.
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The problem is finding Zs for a particular periodic diffraction structure.
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Using the circuit theory anology we find
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The whole problem reduces to finding Zfilter, which may or may not be easy
to deduce.
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| * A. Hessel and A. A. Oliner, "A New Theory of Wood's Anomalies on
Optical Gratings", Applied Optics, 4, 1275-1298, October
1965. |
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