| 摘要 |
<p>Pair of spectacles has a pair of lenses made from e.g. polystyrene which include an X-ray image simulating device comprising linear, identical grooves provided in a planar surface of each lens. Each groove has first and second walls. The grooves of both lenses extend in a parallel manner and are transversely contiguous such that in two adjoining grooves in each of the lenses the first wall of one groove and the second wall of the other groove extend in common intersecting relation. Each first wall extends transversely of the planar surface of each lense, and each second wall is inclined at an acute angle =5 degrees. The grooves in one of the lenses extend transversely of the grooves in the other lens.</p> |
