| 摘要 |
PROBLEM TO BE SOLVED: To settle the situation that a user has a stiff neck and stiff shoulders when the user puts bifocal glasses on and looks at a thing situated above and near the user's face because the user lifts the glass lenses or raises the user's face and sees through lenses (3) for short distance arranged in the lower regions of the glasses lenses. SOLUTION: In bifocal glass lenses, lenses (2) for short distance through which the user looks at a thing situated above and near the user's face are arranged at suitable positions in the upper regions of the glass lenses (1), and lenses (4) for seeing objects at a long distance are arranged in the central regions. When the user looks at a thing situated above and near the user's face using the bifocal glass lenses, the user sees through the lenses (2) for short distance arranged in the the upper regions. COPYRIGHT: (C)2004,JPO
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