# Some topics in extending the C method to multilayer gratings of different profiles

Li 1996: When the interfaces of a layered grating have different profiles, a single coordinate transformation no longer flattens them all. This paper…

Canonical: https://mcgrating.com/publications/li-1996-extending-the-c-method.html


Lifeng Li, G Granet, J P Plumey, J Chandezon

Lifeng Li, G Granet, J P Plumey and J Chandezon, “Some topics in extending the C method to multilayer gratings of different profiles”, Pure Appl. Opt. **5**, 141-156 (1996). [https://doi.org/10.1088/0963-9659/5/2/002](https://doi.org/10.1088/0963-9659/5/2/002)

When the interfaces of a layered grating have *different* profiles, a single coordinate transformation no longer flattens them all. This paper examines the assumption hidden in an earlier recipe for that case, shows where it is and is not justified, and proposes two alternative ways of extending the C method, one of which is as effective as the original recipe.

The distinction the Chandezon codes expose as **Classic** (identical corrugation at all interfaces) versus **Extended** (independent corrugation of every interface, same period, no intersections) is the distinction this paper draws.

**Implemented in**: [Chandezon Collinear](https://mcgrating.com/products.html#chandezon-collinear), [Chandezon Conical](https://mcgrating.com/products.html#chandezon-conical)

**Cited on**: [The C method (Chandezon)](https://mcgrating.com/features/c-method.html) · [Multicoated gratings: a differential formalism applicable in the entire optical region](https://mcgrating.com/publications/chandezon-1982-multicoated-gratings.html)

**Bibliography**: [Reference [4]](https://mcgrating.com/references.html#ref-4)

**Full text**: [Some topics in extending the C method to multilayer gratings of different profiles](https://mcgrating.com/references/ref04.pdf) (PDF, 182 KB)

© 1996 IOP Publishing. This copy is hosted for the convenience of MC Grating users; the version of record is the publisher's, at the DOI above.

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