Method For Determining The Feasibility Of An Ophthalmic Lens

Patent metadata

Field	Value
Publication number	US-2016274376-A1
Application number	US-201314442590-A
Country	US
Kind code	A1
Filing date	Nov 13, 2013
Priority date	Nov 14, 2012
Publication date	Sep 22, 2016
Grant date	—

Abstract

Method for determining the feasibility of an ophthalmic lens by an ophthalmic lens manufacturing process comprising: an ophthalmic lens data providing step, a set of surface parameters providing step, an optical parameters providing step during which a set of n optical parameters (P 1 , P 2 , . . . , P n ) is provided, n being an integer greater than or equal to 1, each optical parameter P i being provided with a tolerance value ε i , —a feasibility check determining step, during which the feasibility of the ophthalmic lens by the ophthalmic lens manufacturing process is determined by determining if for i from 1 to n:

-

ɛ
i

≤

[

∑

j
=
1

m



(

∂

P
i

∂

α
j

)

0

×
Δ




α
j

]

+

A
i

≤

ɛ
i

with




(

∂

P
i

∂

α
j

)

0

the value of the derivative of P i with respect to the jth surface parameter α j on the nominal surface and Δα j the value of the jth surface parameter and A i a combination of terms of order greater or equal to 2 for each P i .

First claim

1 . A method implemented by computer means, for determining the feasibility of an ophthalmic lens by an ophthalmic lens manufacturing process, the ophthalmic lens being adapted for a wearer and comprising at least two optical surfaces at least one of which is to be manufactured by the ophthalmic lens manufacturing process based on a corresponding surface of a nominal ophthalmic lens also named “nominal surface”, the method comprising:
an ophthalmic lens data providing step during which data representing the surfaces of the nominal ophthalmic lens is provided;
a set of surface parameters providing step during which a set of m surface parameters (α 1 , α 2 , . . . , α m ) is provided, m being an integer greater than or equal to 1, the surface parameters representing the differences in position and/or shape of the at least one manufactured surface of an ophthalmic lens with the nominal surface;
an optical parameters providing step during which a set of n optical parameters (P 1 , P 2 , . . . , P n ) is provided, n being an integer greater than or equal to 1, each optical parameter P i being provided with a tolerance value ε i defined in reference to a nominal value P i,0 being the value of the optical parameter P i of the nominal ophthalmic lens; and
a feasibility check determining step, during which the feasibility of the ophthalmic lens by the ophthalmic lens manufacturing process is determined by determining if for i from 1 to n:

-

ɛ
i

≤

[

∑

j
=
1

m





(

∂

P
i

∂

α
j

)

0

×

Δα
j

]

+

A
i

≤

ɛ
i




with




(

∂

P
i

∂

α
j

)

0

the value of the derivative of P i with respect to the jth surface parameter α j on the nominal surface and Δα j the value of the jth surface parameter and A i a combination of terms of order greater or equal to 2 for each P i .

2 . The method according to claim 1 , wherein during the feasibility check determining step at least part, for example all, of the feasibility checks are determined by setting for i from 1 to n:

A
i

=

1
2



[

∑

j
,

k
=
1

m





(

∂
2



P
i

∂

α
j



∂

α
k

)

0

×

Δα
j

×

Δα
k

]




with




(

∂
2



P
i

∂

α
j



∂

Assignees

• Essilor Int

Inventors

• Allione Pascal
• Chauveau Jean-Pierre
• Steigelman Daniel

Classifications

• G02C13/005

  Measuring geometric parameters required to locate ophtalmic lenses in spectacles frames (apparatus for testing or instruments for examining the eyes per se A61B3/00; machines or devices and accessories for grinding the edges of lenses using spectacles as a template B24B9/144) · CPC title

• G02C7/028 Primary

  Special mathematical design techniques · CPC title

• G02C7/027

  considering wearer's parameters · CPC title

• G02C7/024 Primary

  Methods of designing ophthalmic lenses · CPC title