| 摘要 |
An additional lens which can be applied to the rear face of a spectacles frame and is characterised by its thin elastic meniscus shape, the convex face of which is applied by means of pressure to the concave rear face of the main lens in order to remain in place simply by adhesion, or held by the lateral pressure which it exerts over its perimeter against the suitable asperities of the frame. <IMAGE>
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