| 摘要 |
An ophthalmic device having rim members for securing a pair of primary lenses thereto for distant vision, the upper portion of the rim members being located above eye level when worn, at least one pair of auxiliary lenses being tensionally and releasably attached to the device in a piggy-back arrangement, and extending over the primary lenses, preferrably over the rear thereof, and of such a prescription so that the prescription of the combined lenses, primary and auxiliary, provides a bifocal or multifocal lens arrangement, the means for releasably attaching the auxiliary lenses to the rim member being a pair of bracket members attached to the side portions of the rim members, at least one of the bracket members being resilient and capable of spring action, so that at least one of the bracket members will yield relative to the other bracket member, the auxiliary lenses having notches formed in the side portions thereof, the bracket members and the notches in the auxiliary lenses being arranged so that the auxiliary lenses can be snapped onto the bracket members, the bracket members releasably engaging the notched portions of the auxiliary lenses whereby the auxiliary lenses can be interchanged with other lenses for different purposes by the wearer of the device and by removing the auxiliary lenses from the device, the primary lenses become full field distant lenses.
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