| 摘要 |
PROBLEM TO BE SOLVED: To provide a progressive refracting power lens which has a wide bright viewing region while realizing the thickness reduction of the lens by using a shallow base curve. SOLUTION: The lens has a a progressive surface at its rear surface and is provided continuously with a region where the surface refracting power in a main gaze line direction is smaller than the surface refracting power in the direction perpendicular thereto, a point where the surface refracting power in the main gate line is equal to the surface refracting power perpendicular thereto and a region where the surface refracting power in the main gaze line direction is greater than the surface refracting power in the direction perpendicular thereto, the furtherer upward from the fitting point (origin) along the main gaze line direction in the far sight region. The lens satisfies the following conditions: Pm(25)<Ps(25)Pm(35)>Ps(35), where Pm(Y): The surface refracting power (unit: D) in the main gaze line direction at the point on the main gaze line of Y (unit: mm) upward from the origin, and Ps(Y): The surface refracting power (unit: D) in the direction perpendicular to the main gaze line direction at the point on the main gaze line of Y (unit: mm) upward from the origin. COPYRIGHT: (C)2005,JPO&NCIPI
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