IP Library Granted Patent US 6,964,478
Granted Patent B2
US 6,964,478 · App. 10/279,040 · Granted Nov 15, 2005

Progressive spectacle lens

View Patent ↗
Loading inventors, assignments & file history…
Monitor This Case
Get email alerts when status or documents change.
Order Certified Copies
Most orders are placed with the USPTO same day — all within 24 business hours.
Order via The Patent Place →
Pre-filled with this patent's details
Quick Facts
Patent No.
US 6,964,478
App. No.
10/279,040
Granted
Nov 15, 2005
Kind
B2
Abstract

A spectacle lens is provided with a region (distance portion) designed for viewing at greater distances and, in particular, “to infinity”, a region (near portion) designed for viewing at short distances and, in particular, “reading distances”, and a progression zone disposed between the distance portion and the near portion, in which the power of the spectacle lens increases from the value in the distance reference point located in the distance portion to the value at the near reference point located in the near portion along a line (principal meridian) curving towards the nose. The invention is marked by specific conditions for the astigmatic deviation and/or the mean “as worn” power being observed.

Claims (37)

1. Spectacle lens comprising:

a region (distance portion) designed for viewing at greater distances and, in particular, “to infinity”;

a region (near portion) designed for viewing at short distances and, in particular, “reading distances”;

a progression zone disposed between the distance portion and the near portion, in which the power of the spectacle lens increases from the value at the distance reference point located in the distance portion to the value at the near reference point located in the near portion along a line (principal meridian) curving towards the nose;

wherein the astigmatic deviation along the principal meridian, i.e. the difference between the prescribed and the actual astigmatism, is less than 0.2 dpt;

the maximum astigmatic deviation is less than 1.2 times the addition power (add) which is defined as the difference between the mean “as worn” powers at the distance reference point (D BF ) and the near reference point (D BN );

the maximum astigmatic deviation occurs on the nasal side of the principal meridian; and

the value of the maximum astigmatic deviation on the nasal side is at most 0.15 dpt greater than the value of the maximum astigmatic deviation on the temporal side

wherein

the mean “as worn” power D f in the region above the centration point B Z , i.e. for y>y(BZ), is given by

D f ≦0.4·(add)+ D BF ;

the “as worn” power DN in the region for which y<<(BZ)−7 mm is given by

D f ≧0.25·(add)+ D BF ;

the spacing xA (B F ) of the iso-lines for an astigmatic deviation of 0.5 dpt at the level of the distance reference point, i.e. for y=y(B F ), is given by

  xA ( B F )≧0.06/(add);

the spacing xD (B F ) of the iso-lines for a deviation of 0.25 dpt from the mean “as worn” power in the distance reference point is given at the level of the distance reference point, i.e. for y=y(B F ), by

xD ( B F )≧0.04/(add);

the spacing xA (B F ) of the iso-lines for an astigmatic deviation of 0.5 dpt at the level of the near reference point, i.e. for y=y(B N ), is given by

xA ( B N )≧0.015/(add);

the spacing xA (B F ) of the iso-lines for a deviation of 0.25 dpt from the mean “as worn” power in the near reference point is given at the level of the near reference point, i.e. for y=y(B F ), by

xD ( B F )≧0.015/(add).

2. Spectacle lens wherein:

a region (distance portion) designed for viewing at greater distances and, in particular, “to infinity”;

a region (near portion) designed for viewing at short distances and, in particular, “reading distances”;

a progression zone disposed between the distance portion and the near portion, in which the power of the spectacle lens increases from the value at the distance reference point located in the distance portion to the value at the near reference point located in the near portion along a line (principal meridian) curving towards the nose;

wherein the mean “as worn” power D f in the region above the centration point B Z , i.e. for y>y(BZ), is given by

D f ≦0.4·(add)+ D BF ;

the “as worn” power DN in the region for which y<<(BZ)−7 mm is given by

D f ≧0.25·(add)+ D BF ;

the spacing xA (B F ) of the iso-lines for an astigmatic deviation of 0.5 dpt at the level of the distance reference point, i.e. for y=y(B F ), is given by

xA ( B F )≧0.06/(add);

the spacing xD (B F ) of the iso-lines for a deviation of 0.25 dpt from the mean “as worn” power in the distance reference point is given at the level of the distance reference point, i.e. for y=y(B F ), by

xD ( B F )≧0.04/(add);

the spacing xA (B F ) of the iso-lines for an astigmatic deviation of 0.5 dpt at the level of the near reference point, i.e. for y=y(B N ), is given by

xA ( B N )≧0.015/(add);

the spacing xA (B F ) of the iso-lines for a deviation of 0.25 dpt from the mean “as worn” power in the near reference point is given at the level of the near reference point, i.e. for y=y(B F ), by

xD (B F )≧0.015/(add).