| 摘要 |
PROBLEM TO BE SOLVED: To provide a progressive refracting-power lens in which distortion aberrations are suppressed and to provide the manufacturing method thereof. SOLUTION: The progressive refracting-power lens is constituted by forming a progressive refracting surface which is provided with a first region arranged in the upper part of the lens for viewing relatively far, a second region which is arranged lower than the first region and has the refracting power greater than that of the first region and a progressive zone which is arranged between these regions and has the progressively changing refracting power on the inside surface of the lens. When the far-slight diopter and the near-sight diopter are both minus, the progressive refracting-power lens is so formed as to gradually increase the curvature of the curve on the external surface of the lens with separation from the virtual horizontal line passing through the geometric center of the lens relating to the upper part practical area of the curve in the perpendicular direction of the external surface of the lens and to gradually reduce the curvature of the curve on the external surface of the lens with separation from the virtual horizontal line relating to the horizontal line of the lower part practical area. COPYRIGHT: (C)2007,JPO&INPIT
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