US 12,485,633 B2
Method for manufacturing an optical lens by additive manufacturing and corresponding intermediate optical element
Alexandre Gourraud, Charenton le Pont (FR)
Assigned to Essilor International, Charenton-le-Pont (FR)
Appl. No. 17/279,875
Filed by ESSILOR INTERNATIONAL, Charenton le Pont (FR)
PCT Filed Sep. 24, 2019, PCT No. PCT/EP2019/075741
§ 371(c)(1), (2) Date Mar. 25, 2021,
PCT Pub. No. WO2020/064754, PCT Pub. Date Apr. 2, 2020.
Claims priority of application No. 18306258 (EP), filed on Sep. 26, 2018.
Prior Publication US 2021/0394471 A1, Dec. 23, 2021
Int. Cl. B29D 11/00 (2006.01); B29C 64/188 (2017.01); B29C 64/393 (2017.01); B33Y 10/00 (2015.01); B33Y 40/20 (2020.01); B33Y 50/02 (2015.01); B33Y 80/00 (2015.01); G02C 7/02 (2006.01)
CPC B29D 11/00432 (2013.01) [B29C 64/188 (2017.08); B29C 64/393 (2017.08); B33Y 10/00 (2014.12); B33Y 40/20 (2020.01); B33Y 50/02 (2014.12); B33Y 80/00 (2014.12); G02C 7/027 (2013.01)] 17 Claims
OG exemplary drawing
 
1. A method for manufacturing an optical lens by additive manufacturing, comprising steps of:
depositing a first layer having a first thickness,
depositing a second layer, having a second thickness, onto the first layer, said second layer forming a first asperity with the first layer,
depositing a third layer having a third thickness,
depositing a fourth layer having a fourth thickness onto the third layer, thereby forming an intermediate optical element, said fourth layer forming a second asperity with the third layer,
smoothing the first asperity and the second asperity on the intermediate optical element thereby forming the optical lens,
wherein said second thickness and said fourth thickness are different, and wherein a cross sectional area of the first asperity is equal to a cross sectional area of the second asperity,
wherein the method is performed to produce the intermediate optical element with a first end layer, a second end layer and a plurality of layers situated between the first end layer and the second end layer, each of the layers having a thickness and an exposed length,
wherein the thickness increases with the layers from the first end layer to the second end layer and wherein the exposed length decreases from the first end layer to the second end layer, and
wherein, for each of the layers situated between the first end layer and the second end layer, a product of the thickness of the concerned layer by the exposed length of the layer on which the concerned layer is deposited is equal to a product of the thickness of the first end layer by the exposed length of the layer on which the first end layer is deposited.