Progressive spectacle lens with regionally varying refractive index and method for the design of same

Patent metadata

Field	Value
Publication number	US-11086142-B2
Application number	US-202117153581-A
Country	US
Kind code	B2
Filing date	Jan 20, 2021
Priority date	Jul 20, 2018
Publication date	Aug 10, 2021
Grant date	Aug 10, 2021

Abstract

A progressive spectacle lens includes a substrate which has a front face and a rear face and is made from a material with a regionally varying refractive index, wherein the front face and/or the rear face has/have a free-form surface geometry. The progressive spectacle lens complies with the following optical requirements: (1) a prescribed dioptric power in the distance reference point within the permissible limit deviations in accordance with EN ISO 8980-2:2004 and a prescribed dioptric power in the near reference point within the permissible limit deviations in accordance with EN ISO 8980-2:2004, (2) a monotonically steady increase in the dioptric power between the distance reference point and near reference point along a principal line of vision, and (3) a progression channel. The progressive spectacle lens has a free-form surface geometry of the front face and/or rear face.

First claim

The invention claimed is:

1. A product comprising:
a progressive power spectacle lens having a substrate with a front surface and a back surface, the substrate including a material with a spatially varying refractive index,
wherein the front surface has a front surface geometry and the back surface has a back surface geometry,
wherein at least one of the front surface geometry or the back surface geometry is a free-form surface geometry,
wherein the progressive power spectacle lens has a distance design reference point and a near design reference point,
wherein the progressive power spectacle lens is configured to satisfy the following optical requirements:
(1) a prescribed dioptric power at the distance design reference point within an admissible limit deviation pursuant to DIN EN ISO 8980-2:2004 and a prescribed dioptric power at the near design reference point within an admissible limit deviation pursuant to DIN EN ISO 8980-2:2004;
(2) a monotonically increasing gradient of the dioptric power between distance design reference point and near design reference point on a principal line of sight; and
(3) an intermediate corridor, which is defined by virtue of the residual astigmatism lying below a value selected from the group consisting of:
(a) 0.25 diopters,
(b) 0.38 diopters, or
(c) 0.50 diopters,
and wherein the front surface geometry and the back surface geometry are configured such that, compared to a substrate made of a material with a spatially non-varying refractive index of between 1.5 and 1.8, for which at least one of the optical requirements (1) to (3) is not satisfied, the spatial variation of the refractive index of the material of the substrate of the progressive power spectacle lens is configured such that all optical requirements (1) to (3) are satisfied and, wherein in relation to the substrate made of the material with the spatially non-varying refractive index of between 1.5 and 1.8, there is a reduction in the residual astigmatism to the side of the intermediate corridor such that a width of the intermediate corridor increases, wherein the width is defined by a bound of the residual astigmatism in a range between 0.25 diopters and 0.50 diopters.

2. A product comprising:
a representation of a progressive power spectacle lens situated on a non-transitory data medium as computer-readable data with instructions for the production thereof by an additive method or a representation of the progressive power spectacle lens with instructions for the production thereof by an additive method in the form of a computer-readable data signal, wherein:
the progressive power spectacle lens has a substrate with a front surface and a back surface, the substrate including a material with a spatially varying refractive index,
wherein the front surface has a front surface geometry and the back surface has a back surface geometry,
wherein at least one of the front surface geometry or the back surface geometry is a free-form surface geometry,
wherein the progressive power spectacle lens has a distance design reference point and a near design reference point,
wherein the progressive power spectacle lens is configured to satisfy the following optical requirements:
(1) a prescribed dioptric power at the distance design reference point within an admissible limit deviation pursuant to DIN EN ISO 8980-2:2004 and a prescribed dioptric power at the near design reference point within an admissible limit deviation pursuant to DIN EN ISO 8980-2:2004;
(2) a monotonically increasing gradient of the dioptric power between distance design reference point and near design reference point on a principal line of sight; and
(3) an intermediate corridor, which is defined by virtue of the residual astigmatism lying below a value selected from the group consisting of:
(a) 0.25 diopters,
(b) 0.38 diopters, or
(c) 0.50 diopters,

and wherein the front surface geometry and the back surface geometry are configured such that, compared to a substrate made of a material with a spatially non-varying refractive index of between 1.5 and 1.8, for which at least one of the optical requirements (1) to (3) is not satisfied, the spatial variation of the refractive index of the material of the substrate of the progressive power spectacle lens is configured such that all optical requirements (1) to (3) are satisfied and, wherein in relation to the substrate made of the material with the spatially non-varying refractive index of between 1.5 and 1.8, there is a reduction in the residual astigmatism to the side of the intermediate corridor such that a width of the intermediate corridor increases, wherein the width is defined by a bound of the residual astigmatism in a range between 0.25 diopters and 0.50 diopters.

3. A product comprising:
a progressive power spectacle lens having a substrate with a front surface and a back surface, the substrate including a material with a spatially varying refractive index,
wherein the front surface has a front surface geometry and the back surface has a back surface geometry,
wherein at least one of the front surface geometry or the back surface geometry is a free-form surface geometry,
wherein the progressive power spectacle lens has a distance design reference point and a near design reference point,
wherein the progressive power spectacle lens is configured to satisfy the following optical requirements:
(1) a prescribed dioptric power at the distance design reference point within an admissible limit deviation pursuant to DIN EN ISO 8980-2:2004 and a prescribed dioptric power at the near design reference point within an admissible limit deviation pursuant to DIN EN ISO 8980-2:2004;
(2) a monotonically increasing gradient of the dioptric power between distance design reference point and near design reference point on a principal line of sight; and
(3) an intermediate corridor, which is defined by virtue of the residual astigmatism lying below a value selected from the group consisting of:
(a) 0.25 diopters,
(b) 0.38 diopters, or
(c) 0.50 diopters,

wherein
wherein, in a case where the front surface of the progressive power spectacle lens has a free-form surface geometry, the free-form surface geometry of the front surface is modified in relation to a comparison progressive power spectacle lens with a same back surface geometry, with the same dioptric power profile, and with a same residual astigmatism for the spectacle beam paths through a principal line of sight and with a substrate made of a material with a spatially non-varying refractive index, which has a value that corresponds to a value of the spatially varying refractive index of the material of the substrate of the progressive power spectacle lens at the point of the principal line of sight on the front surface at which the progressive power spectacle lens with the substrate made of the material with a spatially varying refractive index experiences half of an entire dioptric power increase, and the modified free-form surface geometry of the front surface of the progressive power spectacle lens and the spatial variation of the refractive index are adapted to one another such that, for the progressive power spectacle lens, a first value of the surface astigmatism of the front surface, ascertained by calculation, at a point through which the associated spectacle wearer beam path extends through the location of the principal line of sight, at which the progressive power spectacle lens experiences half of the entire mean power increase, is greater than a second value of the surface astigmatism of the front surface with a free-form surface geometry, ascertained by calculation for the comparison progressive power spectacle lens from a material with a spatially non-varying refractive index, at the point at which the associated spectacle wearer beam path extends throug

Assignees

• Zeiss Carl Vision Int Gmbh

Inventors

• Kelch Gerhard
• Menke Christoph
• Wietschorke Helmut

Classifications

• G02C7/063 Primary

  Shape of the progressive surface · CPC title

• G02C2202/12

  Locally varying refractive index, gradient index lenses · CPC title

• G02C7/065 Primary

  Properties on the principal line · CPC title

• G02C7/068

  Special properties achieved by the combination of the front and back surfaces · CPC title