| 摘要 |
PROBLEM TO BE SOLVED: To provide a bifocal contact lens having a good wearing feel and having a clear visual field for both a distant vision and a near vision and satisfactory viewing quality. SOLUTION: The bifocal lens is characterized by that its central optical part of a circular shape has a degree of distant vision correction power, a peripheral optical part of an annular shape positioned on the outer periphery thereof has a degree of near vision correction power and, on the other hand, the lens outer peripheral portion which is a non-optical region positioned on the outer periphery is provided with an inflection part. The thickness Tj (mm) in the curvature direction of the juncture between the peripheral optical part and the lens outer peripheral part is within a range regulated by an equation: 0.15≤Tj≤0.25 P≥-6.00-0.018xP+0.0432≤Tj≤-0.018xP+0.1432 P<-6.00 in a range of each refracting power P (D: Diopter). COPYRIGHT: (C)2005,JPO&NCIPI
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