Method for reducing the thickness of a lens shape and uncut lens blank

Patent metadata

Field	Value
Publication number	US-9864212-B2
Application number	US-201514719039-A
Country	US
Kind code	B2
Filing date	May 21, 2015
Priority date	May 22, 2014
Publication date	Jan 9, 2018
Grant date	Jan 9, 2018

Abstract

The current invention is directed to a method, in particular a computer-implemented method, for providing a modified lens design for an uncut lens blank, in particular through the use of a non-transitory computer readable medium. Further, a method, in particular a computer-implemented method, for reducing a thickness of an original lens design of an uncut lens blank, in particular through the use of a non-transitory computer readable medium, is provided. Furthermore, a method for manufacturing an uncut lens blank and an uncut lens blank are provided.

First claim

What is claimed is:

1. A computer-implemented method for providing a modified lens shape for an uncut lens blank comprising the following steps:
a) providing an original lens shape of an uncut lens blank having a front surface and a back surface, wherein the original lens shape comprises an original shape of the front surface and an original shape of the back surface of the uncut lens blank, wherein the uncut lens blank has predetermined optical properties;
b) determining a boundary line on the back surface, wherein a curvature profile of the original shape of the back surface is to be preserved within the boundary line;
c) determining a boundary curvature of the back surface at the boundary line;
d) determining a new curvature profile of the back surface between the boundary line and an outer edge of the uncut lens blank, wherein a curvature of the new curvature profile at the boundary line equals the boundary curvature and transitions monotonically and continuously towards the outer edge from the boundary curvature towards a predefined curvature value; and,
e) determining a modified lens shape of the uncut lens blank, wherein the modified lens shape comprises the original shape of the front surface, and a modified shape of the back surface, wherein the modified shape of the back surface is determined by an optimization procedure based on the new curvature profile towards a target shape, and wherein the target shape includes the preserved curvature profile of the original lens shape within the boundary line and a thickness requirement for the outer edge of the uncut lens blank; and,
f) manufacturing the uncut lens blank according to the modified lens shape.

2. The method according to claim 1 , wherein the curvature of the back surface is continuous.

3. The method according to claim 1 , wherein the uncut lens blank is a unitary element made of a single material.

4. The method according to claim 1 , wherein the original lens shape provides for a positive focal power, wherein the predefined curvature value is a predetermined upper threshold curvature value, and wherein, as the thickness requirement, a predefined value for a smallest thickness of the outer edge of the uncut lens blank is applied as a mandatory condition.

5. A computer-implemented method for providing a modified lens shape for an uncut lens blank comprising the following steps:
a) providing an original lens shape of an uncut lens blank having a front surface and a back surface, wherein the original lens shape comprises an original shape of the front surface and an original shape of the back surface of the uncut lens blank, wherein the uncut lens blank has predetermined optical properties;
b) determining a boundary line on the back surface, wherein a curvature profile of the original shape of the back surface is to be preserved within the boundary line;
c) determining a boundary curvature of the back surface at the boundary line;
d) determining a new curvature profile of the back surface between the boundary line and an outer edge of the uncut lens blank, wherein a curvature of the new curvature profile at the boundary line equals the boundary curvature and transitions monotonically and continuously towards the outer edge from the boundary curvature towards a predefined curvature value; and,
e) determining a modified lens shape of the uncut lens blank, wherein the modified lens shape comprises the original shape of the front surface, and a modified shape of the back surface, wherein the modified shape of the back surface is determined by an optimization procedure based on the new curvature profile towards a target shape, and wherein the target shape includes the preserved curvature profile of the original lens shape within the boundary line and a thickness requirement for the outer edge of the uncut lens blank;
wherein the original lens shape provides for a positive focal power, wherein the predefined curvature value is a predetermined upper threshold curvature value, and wherein, as the thickness requirement, a predefined value for a smallest thickness of the outer edge of the uncut lens blank is applied as a mandatory condition; and,
wherein the mandatory condition is applied so that, during the optimization process, a sagittal height of the preserved curvature profile of the original lens shape of the back surface within the boundary line is adjusted while the preserved curvature profile is maintained; and,
f) manufacturing the uncut lens blank according to the modified lens shape.

6. A computer-implemented method for providing a modified lens shape for an uncut lens blank comprising the following steps:
a) providing an original lens shape of an uncut lens blank having a front surface and a back surface, wherein the original lens shape comprises an original shape of the front surface and an original shape of the back surface of the uncut lens blank, wherein the uncut lens blank has predetermined optical properties;
b) determining a boundary line on the back surface, wherein a curvature profile of the original shape of the back surface is to be preserved within the boundary line;
c) determining a boundary curvature of the back surface at the boundary line;
d) determining a new curvature profile of the back surface between the boundary line and an outer edge of the uncut lens blank, wherein a curvature of the new curvature profile at the boundary line equals the boundary curvature and transitions monotonically and continuously towards the outer edge from the boundary curvature towards a predefined curvature value; and,
e) determining a modified lens shape of the uncut lens blank, wherein the modified lens shape comprises the original shape of the front surface, and a modified shape of the back surface, wherein the modified shape of the back surface is determined by an optimization procedure based on the new curvature profile towards a target shape, and wherein the target shape includes the preserved curvature profile of the original lens shape within the boundary line and a thickness requirement for the outer edge of the uncut lens blank;
wherein the original lens shape provides for a positive focal power, wherein the predefined curvature value is a predetermined upper threshold curvature value, and wherein, as the thickness requirement, a predefined value for a smallest thickness of the outer edge of the uncut lens blank is applied as a mandatory condition; and,
wherein a second optimization is conducted subsequent to step e), wherein the second optimization uses the modified shape of the back surface as an initial shape and optimizes only the curvature profile within the boundary line towards the predetermined optical properties of the uncut lens blank; and,
f) manufacturing the uncut lens blank according to the modified lens shape.

7. A computer-implemented method for providing a modified lens shape for an uncut lens blank comprising the following steps:
a) providing an original lens shape of an uncut lens blank having a front surface and a back surface, wherein the original lens shape comprises an original shape of the front surface and an original shape of the back surface of the uncut lens blank, wherein the uncut lens blank has predetermined optical properties;
b) determining a boundary line on the back surface, wherein a curvature profile of the original shape of the back surface is to be preserved within the boundary line;
c) determining a boundary curvature of the back surface at the boundary line;
d) determining a new curvature profile of the back surface between the boundary line and an outer edge of the uncut lens blank, wherein a curvature of the new curvature profile at the boundary line equals the boundary curvature and transitions monotonically and continuously towards the outer ed

Assignees

• Zeiss Carl Vision Int Gmbh
• Zeiss Carl Vision Inc

Inventors

• Spratt Ray Steven
• Kratzer Timo
• Ellinger Philipp

Classifications

• G02C7/024

  Methods of designing ophthalmic lenses · CPC title

• G02C2202/22

  Correction of higher order and chromatic aberrations, wave front measurement and calculation · CPC title

• G02C2202/08

  Series of lenses, lens blanks · CPC title

• G02C7/028

  Special mathematical design techniques · CPC title

• G02C7/027 Primary

  considering wearer's parameters · CPC title