| 摘要 |
<p>Spectacles permitting adjustment of the distance between the lens frames have a hollow slide holder (7,7a) fixed to the top of each lens frame (1,2). A bridge (8) passes through both slide holders. The lens frames can be moved towards or away from one another and fixed in required positions by fixing the slide holders to the bridge by suitable means, e.g., the bridge has a series of threaded holes formed along its length, e.g., at 3 mm intervals and stop screws (93) are screwed in these holes. Alternatively, a single slide holder projects from one frame, a bridge projects from the other frame and into this holder, and the frames are supported by and individually adjustable on a main frame. Fitting of spectacles and selection of lenses are easier when an extra wide or extra narrow inter-frame gap is needed.</p> |
