| 摘要 |
The present invention provides a progressive-power lens affording superior wear comfort, even where a shallow base curve is employed in order to make the lens lighter and thinner, which is desirable in the terms of weight and aesthetic design. In the case of a progressive-power lens for correcting hyperopia whose distance portion has a positive refractive power, such lens is designed by giving preference to minimizing transmission astigmatism at each point on the principal sight line of the distance portion, but not giving preference to making the astigmatism of the lens surface zero at each point on the principal sight line. On the other hand, in the case of a myopia corrective progressive-power lens for correcting myopia whose distance portion has a negative refractive power, such lens is designed by giving preference to minimizing transmission average refractive power error at each point on the principal sight line of the distance portion, but not to making the astigmatism of lens surface zero at each point on the principal sight line.
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