| 摘要 |
<p>In a method of forming a contrast mask of a photographic original (17) in a photochromic body (11) by illuminating the body through the original, the body (11) is associated with a surface (20) which reflects into the body (11) radiation which has passed through the original and the body. The surface (20) may be a surface coating on a substrate (19), or may be on the body (11), the latter being particularly suitable for a lens in spectacles or sunglasses. The mask may be cleared using non-liquid heating means, for example microwave, hot air, infrared radiation, or an electrically conductive coating on at least one surface of the body.</p> |
