SMS freeforms for illumination

Benitez Gimenez, Pablo and Miñano Dominguez, Juan Carlos and Chaves, Julio and Santamaria Galdon, Maria Asuncion (2013). SMS freeforms for illumination. "Advanced Optical Technologies", v. 2 (n. 4); pp. 323-329. ISSN 2192-8576.


Title: SMS freeforms for illumination
  • Benitez Gimenez, Pablo
  • Miñano Dominguez, Juan Carlos
  • Chaves, Julio
  • Santamaria Galdon, Maria Asuncion
Item Type: Article
Título de Revista/Publicación: Advanced Optical Technologies
Date: August 2013
ISSN: 2192-8576
Volume: 2
Freetext Keywords: étendue; freeform; optical design; SMS
Faculty: E.T.S.I. Telecomunicación (UPM)
Department: Electrónica Física
Creative Commons Licenses: Recognition - No derivative works - Non commercial

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SMS 3D (simultaneous multiple surfaces in their three-dimensional version) is a well-known design method comprising two freeform surfaces that allow the perfect coupling of two wavefronts with another two. The design algorithm provides a collection of line pairs on both surfaces (called SMS spines), whose three-dimensional shape seems arbitrary at first sight. This paper shows that the shapes of the spines are partially governed by applying the étendue conservation theorem to the biparametric bundle of rays linking the paired spines, which is one lesser known étendue invariants found by Poincaré. The resulting formulae for the spines in three-dimensional space happen to coincide with the conventional étendue formulas of two-dimensional geometry, like for instance, the Hottel formula.

More information

Item ID: 25896
DC Identifier:
OAI Identifier:
DOI: 10.1515/aot-2013-0025
Official URL:
Deposited by: Memoria Investigacion
Deposited on: 17 May 2014 10:25
Last Modified: 22 Sep 2014 11:38
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