| 摘要 |
PROBLEM TO BE SOLVED: To make an easily visible visual field larger even when a user views both far and near with bifocal spectacles formed by largely cutting out the lower edges of lenses for near sight in such a manner that the user views a short-distance object, such as a book, with the naked eyes from the lower side of the lenses at the time of viewing such object. SOLUTION: Recessed parts 15 exist downward and inward from optical axes L and open diagonally downward on the inner side are formed at a pair of the right and left lenses for near sight so that the user views the short- distance object with the naked eyes through these recessed parts 15.
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