US 12,135,407 B2
Optical lens having an enhanced interferential coating and a multilayer system for improving abrasion-resistance
Christophe Valenti, Charenton-le-pont (FR); Frédéric Guillain, Charenton-le-pont (FR); William Trottier-Lapointe, Charenton-le-pont (FR); and Xingzhao Ding, Singapore (SG)
Assigned to Essilor International, Charenton-le-Pont (FR)
Appl. No. 17/293,183
Filed by Essilor International, Charenton-le-pont (FR)
PCT Filed Nov. 18, 2019, PCT No. PCT/EP2019/081681
§ 371(c)(1), (2) Date May 12, 2021,
PCT Pub. No. WO2020/104388, PCT Pub. Date May 28, 2020.
Claims priority of application No. 18306522 (EP), filed on Nov. 19, 2018.
Prior Publication US 2022/0011469 A1, Jan. 13, 2022
Int. Cl. G02B 1/116 (2015.01); G02C 7/02 (2006.01)
CPC G02B 1/116 (2013.01) [G02C 7/022 (2013.01)] 23 Claims
OG exemplary drawing
 
1. An optical lens comprising:
a substrate having a front main face and a rear main face, at least one main face of which being successively coated with:
one or more functional coatings such as an abrasion and/or scratch resistant coating;
(A) a first high refractive index sheet having a refractive index higher than 1.55, which does not comprise any Ta2O5 layer;
(B) a second low refractive index sheet having a refractive index of 1.55 or less in direct contact with the former sheet;
(C) a third high refractive index sheet having a refractive index higher than 1.55 in direct contact with the former sheet;
a monolayer sub-layer having a thickness higher than or equal to 50 nm in direct contact with the former sheet (C);
a multilayer interferential coating comprising a stack of at least one high refractive index layer having a refractive index higher than 1.55 and at least one low refractive index layer having a refractive index of 1.55 or less, the refractive indexes being expressed for a wavelength of 550 nm; and
wherein said multilayer interferential coating exhibits the following characteristic:
the scotopic luminous reflection R on at least one main face is lower than or equal to 1.5% for an angle of incidence lower than 35°, Rs being defined by:

OG Complex Work Unit Math
where R(λ) is the reflectance at a given wavelength λ, V′(λ) is the eye sensitivity function for scotopic conditions defined in CIE 1951 and D65(λ) is a reference illuminant corresponding to the solar spectrum; or
the mean reflection factor RsNIR for near infrared light on at least one main face, calculated between 780 nm and 2000 nm and weighted by the function Illum (λ) defined in the ISO 13666:1998 standard, is lower than or equal to 5% for an angle of incidence lower than 35°; or
the mean light reflection factor as a function of incident angle Rv(θ) on at least one main face has a minimum value Rvmin for an angle of incidence θmin comprised in the range [20°-50°] and Rvmin/Rv(15°)<0.95, Rv(15°) being the mean light reflection factor for an angle of incidence θ of 15° on said main face, defined in the ISO 13666:1998 standard.