| 摘要 |
A progressive power lens having a positive vertex power in a distance portion is provided. At least a back surface of the progressive power lens is configured as a progressive surface. The progressive power lens satisfies a condition: <maths id="MATH-US-00001" num="00001"> <MATH OVERFLOW="SCROLL"> <MTABLE> <MTR> <MTD> <MROW> <MROW> <MI>Pf</MI> <MO>+</MO> <MFRAC> <MI>ADD</MI> <MN>3</MN> </MFRAC> </MROW> <MO><</MO> <MROW> <MI>D</MI> <MO></MO> <MSTYLE> <mspace width="0.3em" height="0.3ex"/> </MSTYLE> <MO></MO> <MN>1</MN> </MROW> <MO><</MO> <MROW> <MI>Pf</MI> <MO>+</MO> <MI>ADD</MI> </MROW> </MROW> </MTD> <MTD> <MROW> <MO>(</MO> <MN>1</MN> <MO>)</MO> </MROW> </MTD> </MTR> </MTABLE> </MATH> </MATHS> where Pf represents a vertex power in the distance portion along a vertical cross-section, ADD represents an addition power, and D 1 represents a surface power of a front surface.
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