Method for creating a design of a prescription surface of a multifocal lens and multifocal lens comprising such a prescription surface

Patent metadata

Field	Value
Publication number	US-10831041-B2
Application number	US-201615563390-A
Country	US
Kind code	B2
Filing date	Jan 26, 2016
Priority date	Mar 30, 2015
Publication date	Nov 10, 2020
Grant date	Nov 10, 2020

Abstract

In a method for creating a design of a prescription surface of a multifocal lens, in particular for a progressive spectacle lens, at first data and second data for describing at least one aberration of an eye of a proband for a first situation of use and a second situation of use, respectively, are obtained, and then a first set of parameters and a second set of parameters of a predetermined prescription surface equation are determined from the first and second data, wherein the prescription surface equation is assigned to a first reference point of the prescription surface for the first set of parameters, and is assigned to a second reference point of the prescription surface for the second set of parameters.

First claim

The invention claimed is:

1. A method for producing a design of a prescription surface of a multifocal lens comprising:
obtaining first data for describing at least one aberration of an eye of a proband for a first situation of use and second data for describing the at least one aberration of the eye of the proband for a second situation of use different from the first situation of use;
providing a prescription surface equation describing the prescription surface using a set of parameters that are changing in a controlled manner at the different coordinates of the prescription surface;
determining a first set of parameters and a second set of parameters of the predetermined prescription surface equation from the first and second data;
assigning the first set of parameters to a first reference point of the prescription surface for the first set of parameters, and assigning the second set of parameters to a second reference point of the prescription surface different from the first reference point for the second set of parameters;
obtaining further sets of parameters of the prescription surface equation at further coordinates of the prescription surface, respectively, by interpolating the first set of parameters and the second set of parameters; and
determining, by using the prescription surface equation, prescription surface values of the multifocal lens at the first reference point on the basis of the first set of parameters, at the second reference point on the basis of the second set of parameters, and at the further coordinates of the prescription surface on the basis of the further sets of parameters, respectively, wherein the prescription surface values are determined in a u/v coordinate system using arrow heights of the prescription surface according to the following equation:

z
⁡

(

u
,
v

)

=

r
2

⁢
c

1
+

1
-

r
2

⁢

c
2

with
⁢

⁢
c

=

c
u

⁢

cos
2

⁢
α

+

c
v

⁢

sin
2

⁢
α

=

c
u

⁢

u
2

r
2

+

c
v

⁢

v
2

r
2

⁢

⁢
and
⁢

⁢

r
2

=

u
2

+

v
2

where
z is an arrow height
u is the direction of a first main section
v is the direction of a second main section
C u is the curvature of a main section along the u axis
C v is the curvature of a main section along the v axis
α is the axial position of a meridional section at the coordinate u, v.

2. The method according to claim 1 , wherein the prescription surface equation is a toroidal equation.

3. The method according to claim 1 , wherein the interpolation of the further sets of parameters of the prescription surface equation in is performed in a parameter space of power vectors.

4. The method according to claim 1 , wherein the interpolation of the further sets of parameters of the prescription surface equation is performed in a power vector notation of the parameters.

5. The method according to claim 4 , wherein the interpolation of the further sets of parameters of the prescription surface equation is performed by means of the following power vector equation:
{right arrow over (P)} c ( x,y )=ƒ( x, y ) {right arrow over (P)} cF +(1−ƒ( x, y )) {right arrow over (P)} cN

wherein:
P c (x,y): power vector

P
->

c

=

(

M

J
0

J
45

)

=

(

0
,

Assignees

• Rodenstock Gmbh

Inventors

• Altheimer Helmut
• Becken Wolfgang
• Esser Gregor
• Müller Werner
• Muschielok Adam
• Zimmerman Martin

Classifications

• G02C7/065 Primary

  Properties on the principal line · CPC title

• G02C7/028

  Special mathematical design techniques · CPC title