Patent ID: 6808263
Filing Date: 2004-10-26
Classification: G02C

Abstract:
Spectacle lens comprisinga region (distance portion) designed for viewing at large distances and in particular â€œto infinityâ€ ; a region (near portion) designed for viewing at short distances and in particular â€œreading distancesâ€ ; and a progressive zone disposed between the distance portion and the near portion, in which the power of the spectacle lens increases from a value at a distance reference point located in the distance portion to a value at the near reference point located in the near portion along a curve (principal line) veering towards the nose; wherein to minimize a dynamic distortion, track curves (trajectories relative to a stationary point at (0, 0)) formed by connecting points of intersection of image-side principal rays passing through a center of rotation of an eye with a projection plane at a distance s from an object-side vertex of the spectacle lens, when horizontally moving objects having coordinates (xâˆ’dx, y, s) at a beginning of a movement and (x+dx, y, s) at an end of a movement are imaged through the progressive spectacle lens with r=0 mm, s=âˆ’40 mm and dx=35 mm, satisfy the following condition: the absolute value of a difference between a minimum and a maximum y coordinate of a trajectory is smaller than a value H given in the following table: Sph = âˆ’4.0 dpt, Add = 1.0 dpty = âˆ’5 mmx[mm]âˆ’30.0000âˆ’20.000020.000030.0000H[mm]0.18560.12330.09170.1602y = âˆ’10 mmx[mm]âˆ’30.0000âˆ’20.000020.000030.0000H[mm]0.52940.36390.26810.4506Sph = âˆ’4.0 dpt, Add = 2.0 dpty = âˆ’5 mmx[mm]âˆ’30.0000âˆ’20.000020.000030.0000H[mm]0.05780.03200.00320.0354y = âˆ’10 mmx[mm]âˆ’30.0000âˆ’20.000020.000030.0000H[mm]0.36010.24960.13340.2765Sph = âˆ’4.0 dpt, Add = 3.0 dpty = âˆ’5 mmx[mm]âˆ’30.0000âˆ’20.000020.000030.0000H[mm]0.07640.06480.09190.0754y = âˆ’10 mmx[mm]âˆ’30.0000âˆ’20.000020.000030.0000H[mm]0.14250.10880.02970.0702Sph = 0.5 dpt, Add = 1.0 dpty = âˆ’5 mmx[mm]âˆ’30.0000âˆ’20.000020.000030.0000H[mm]0.23990.16450.14940.2164y = âˆ’10 mmx[mm]âˆ’30.0000âˆ’20.000020.000030.0000H[mm]0.42500.28870.26840.3859Sph = 0.5 dpt, Add = 2.0 dpty = âˆ’5 mmx[mm]âˆ’30.0000âˆ’20.000020.000030.0000H[mm]0.45350.30590.29450.4156y = âˆ’10 mmx[mm]âˆ’30.0000âˆ’20.000020.000030.0000H[mm]0.71020.47170.48020.6734Sph = 0.5 dpt, Add = 3.0 dpty = âˆ’5 mmx[mm]âˆ’30.0000âˆ’20.000020.000030.0000H[mm]0.70380.46460.45080.6353y = âˆ’10 mmx[mm]âˆ’30.0000âˆ’20.000020.000030.0000H[mm]1.06530.68460.76211.0458Sph = +5.0 dpt, Add = 1.0 dpty = âˆ’5 mmx[mm]âˆ’30.0000âˆ’20.000020.000030.0000H[mm]0.86070.58280.49440.7478y = âˆ’10 mmx[mm]âˆ’30.0000âˆ’20.000020.000030.0000H[mm]11.62231.24401.03751.5808Sph = +5.0 dpt, Add = 2.0 dpty = âˆ’5 mmx[mm]âˆ’30.0000âˆ’20.000020.000030.0000H[mm]1.19210.79030.71061.0740y = âˆ’10 mmx[mm]âˆ’30.0000âˆ’20.000020.000030.0000H[mm]11.32041.51191.35122.0477Sph = +5.0 dpt, Add = 3.0 dpty = âˆ’5 mmx[mm]âˆ’30.0000âˆ’20.000020.000030.0000H[mm]1.62901.05240.99971.4771y = âˆ’10 mmx[mm]âˆ’30.0000âˆ’20.000020.000030.0000H[mm]10.96371.86001.81102.6494