| 摘要 |
PROBLEM TO BE SOLVED: To provide a multifocal spectacles lens capable of advantageously securing clearness in the visual confirmation of a far point and a near point, restraining the occurrence of image jump and ghost and made excellent in feeling in usage. SOLUTION: In the multifocal spectacles lens, a vision correction area 12 is constituted of a central vision correction area 14 and an outer peripheral vision correction area 16, an intermediate area 18 and an intermediate distance vision correction area 30 positioned concentrically with respect to an optical center axis: P, and the frequency distribution in a radial direction in the areas 14 and 16 is set by a 0-th formula concerning a distance from the optical center axis: P. In the multifocal spectacles lens, the frequency distribution in the radial direction in the area 18 coupling the vision areas is set by two quadratic expressions, while the frequency distribution in the radial direction in the area 30 is set to draw a recessed or projecting smooth curve from the lens degree Pc of the area 16 to the lens degree Pc thereof by a radial direction inside degree variation area 32 and a radial direction outside degree variation area 34. COPYRIGHT: (C)2005,JPO&NCIPI
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