Structure of spectacle lens for middle to advanced age

摘要

(57) Abstract Objective The middle aged adjustment power of the eye approximately 0.7 - 1dBecause (jioputori) it decreases to weakness, because of that, book-reading apparent businessWith glass lens frequency for the far viewing of the visibility depth which is visible with glass lens frequencyThe visibility depth which is visible and the visibility which is not visible clearly in center (45 -100cm) interval occurring, very much inconvenience to daily life the impressionSlyly it is the thing. To solve this trouble, at the same time book-reading easilyIn order to finish, devising is middle to advanced age of this plan the spectacle lensIt is structure. Constitution In upper half strongly part 2 of spectacle lens 5 upper partThe necessary inclination change where frequency augments from 1 facing toward the lower partTo administer glass lens processing of frequency, in the part 4 of half weakness of the lower partIt makes the configuration which administers single glass lens processing of the number of necessary book-reading apparent suppliesru.