To compensate the degradation in the visual distance regulating power of a person of advanced age and to enable the person of advanced age to read all characters without replacing the spectacles by using auxiliary lenses simply when the person of advanced age wears only the spectacles for far and middle distances.
If the person of advanced age places the two auxiliary lenses of a focal length approximately equal to that of spectacle lenses for far and middle distances in front of the spectacles for far and middle distances, the person can read a newspaper of a close range. If one auxiliary lenses is half rotated around the axis of rotation between the lenses, the total three lenses with the lenses of the spectacles worn by the person overlap one another. As a result, the magnification equal to that of a magnifier can be obtained and further the reading of the fine characters is made possible.
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