US 11,709,299 B2
Optical assembly with protective coating
Gregg A. Ambur, San Clemente, CA (US); Benjamin G. Sonnek, Mahtomedi, MN (US); Jo A. Etter, Kirkland, WA (US); Timothy L. Wong, St. Paul, MN (US); Thomas P. Klun, Lakeland, MN (US); Richard J. Pokorny, Maplewood, MN (US); Benjamin R. Coonce, South St. Paul, MN (US); Douglas S. Dunn, Woodbury, MN (US); Henry A. Kostalik, IV, Minneapolis, MN (US); Christopher S. DeGraw, Eagan, MN (US); John R. Jacobson, Newport, MN (US); Chunjie Zhang, Shoreview, MN (US); and Jung-Sheng Wu, Woodbury, MN (US)
Assigned to 3M INNOVATIVE PROPERTIES COMPANY, St. Paul, MN (US)
Appl. No. 17/44,685
Filed by 3M INNOVATIVE PROPERTIES COMPANY, St. Paul, MN (US)
PCT Filed Jun. 7, 2019, PCT No. PCT/IB2019/054778
§ 371(c)(1), (2) Date Oct. 1, 2020,
PCT Pub. No. WO2019/239271, PCT Pub. Date Dec. 19, 2019.
Claims priority of provisional application 62/685,119, filed on Jun. 14, 2018.
Prior Publication US 2021/0364682 A1, Nov. 25, 2021
Int. Cl. G02B 5/28 (2006.01); G02B 1/04 (2006.01); G02B 1/14 (2015.01); G02B 5/30 (2006.01); G02B 5/08 (2006.01); B29D 11/00 (2006.01)
CPC G02B 5/285 (2013.01) [G02B 1/041 (2013.01); G02B 1/14 (2015.01); G02B 5/287 (2013.01); G02B 5/305 (2013.01); B29D 11/00548 (2013.01); G02B 5/0816 (2013.01); G02B 5/3025 (2013.01)] 17 Claims
OG exemplary drawing
 
1. An optical assembly, comprising an optical element insert molded directly onto an optical stack, the optical stack comprising an optical film and a liner, the optical film being disposed between the optical element and the liner,
wherein the optical film comprises a plurality of alternating polymeric layers reflecting or transmitting light primarily by optical interference, each location over at least 80% of a total area of the optical film having a reflectance greater than about 80% for normally incident light having a same predetermined wavelength and a same first polarization state,
wherein the liner is removable from the optical film,
wherein the optical film comprises a protective coating facing the liner and having an average thickness of no more than 30 micrometers, and
wherein the protective coating comprises an at least partially cured composition, the composition comprising:
a) 70 to 96 weight percent of urethane (meth)acrylate compound having an average (meth)acrylate functionality of 2 to 9.5, based on the total weight of components a) to d);
b) 2 to 20 weight percent of (meth)acrylate monomer having a (meth)acrylate functionality of 1 to 2, based on the total weight of components a) to d), wherein the (meth)acrylate monomer does not comprise a urethane (meth)acrylate compound;
c) optional 0.5 to 2 weight percent of silicone (meth)acrylate, based on the total weight of components a) to d);
d) optional effective amount of photoinitiator;
e) optional inorganic nanoparticles; and
f) optional solvent.