US 9,810,822 B2
Angular optical filtering element for angular filtering having controlled angular selectivity
Emilie Sakat, Gometz-la-Ville (FR); Riad Haïdar, Paris (FR); Jean-Luc Pelouard, Paris (FR); Patrick Bouchon, Verrières-le-Buisson (FR); and Grégory Vincent, Massy (FR)
Assigned to CENTRE NATIONAL DE LA RECHERCHE SCIENTIFIQUE—CNRS, Paris (FR); and Office National d'Etudes et de Recherches Aérospatiales—ONERA, Palaiseau (FR)
Appl. No. 14/899,438
Filed by CENTRE NATIONAL DE LA RECHERCHE SCIENTIFIQUE, Paris (FR); and OFFICE NATIONAL D'ETUDES ET DE RECHERCHES AÉROSPATIALES, Châtillon (FR)
PCT Filed Jun. 17, 2014, PCT No. PCT/EP2014/062766
§ 371(c)(1), (2) Date Dec. 17, 2015,
PCT Pub. No. WO2014/202636, PCT Pub. Date Dec. 24, 2014.
Claims priority of application No. 13 55653 (FR), filed on Jun. 17, 2013.
Prior Publication US 2016/0146989 A1, May 26, 2016
Int. Cl. G01J 5/20 (2006.01); G02B 5/20 (2006.01); G02B 5/00 (2006.01); G02B 5/18 (2006.01); G01J 1/04 (2006.01); G02B 5/22 (2006.01); G02B 5/26 (2006.01); G02B 5/28 (2006.01)
CPC G02B 5/208 (2013.01) [G01J 1/0492 (2013.01); G01J 5/20 (2013.01); G02B 5/008 (2013.01); G02B 5/1809 (2013.01); G02B 5/201 (2013.01); G02B 5/203 (2013.01); G02B 5/22 (2013.01); G02B 5/26 (2013.01); G02B 5/281 (2013.01); G02B 5/288 (2013.01); G01J 2005/202 (2013.01)] 16 Claims
OG exemplary drawing
 
1. An angular optical filtering element (Ei) optimized for the angular filtering about a given angle of incidence of operation (θi, φi), within a given spectral band, comprising:
a first nanostructured band-pass spectral filter (11i, 301), comprising, within said spectral band, a first filtering central wavelength which exhibits a first angular dispersion curve, the angular dispersion curve representing the variation of the first filtering central wavelength determined as a function of the angle of incidence on the optical filtering element (Ei);
a second nanostructured band-pass spectral filter (12i, 302), comprising, within said spectral band, a second filtering central wavelength which exhibits a second angular dispersion curve representing the variation of the second filtering central wavelength determined as a function of the angle of incidence on the optical filtering element (Ei), the second angular dispersion curve being secant with the first angular dispersion curve around the angle of incidence of operation (θi, φi).