US 12,258,658 B2
Method of manufacturing a linearly variable optical filter
Tobias Geldhauser, Wangs (CH); and Petra Greussing, Meiningen (CH)
Assigned to OPTICS BALZERS AG, Balzers (LI)
Appl. No. 17/415,960
Filed by Optics Balzers AG, Balzers (LI)
PCT Filed Nov. 22, 2019, PCT No. PCT/EP2019/025416
§ 371(c)(1), (2) Date Jun. 18, 2021,
PCT Pub. No. WO2020/126073, PCT Pub. Date Jun. 25, 2020.
Claims priority of application No. 10 2018 133 062.6 (DE), filed on Dec. 20, 2018.
Prior Publication US 2022/0074038 A1, Mar. 10, 2022
Int. Cl. C23C 14/04 (2006.01); C23C 14/00 (2006.01); G01J 3/12 (2006.01); G02B 5/28 (2006.01)
CPC C23C 14/042 (2013.01) [C23C 14/0021 (2013.01); G01J 3/12 (2013.01); G02B 5/285 (2013.01); G01J 2003/1234 (2013.01)] 12 Claims
OG exemplary drawing
 
1. Method for producing a spectral gradient filter on a substrate comprising the steps of:
providing the substrate with a first surface to be coated
providing a shadow mask that comprises at least one opening surrounded by an edge, wherein the geometry of the shadow mask is adjusted to a desired gradient profile of the gradient filter
creating a masked substrate by fixing the shadow mask on the first substrate surface to be coated in such a way that parts of the first substrate surface are covered, but the first substrate surface is exposed in the coating area,
inserting the masked substrate into a coating system which is based on physical deposition from the gas phase (PVD), and
carrying out the PVD coating,
wherein
at least parts of the shadow mask lie directly on the surface of the substrate so that no vapour migration occurs in an area of these parts during the coating and wherein the shadow mask is fixed to the substrate in a mechanically detachable manner so that the shadow mask can be used for several coatings.