| 摘要 |
<p>A pencil has a pencil casing made of a sharpenable casing material and a core held in a central receiving bore in the casing material that extends in the longitudinal direction of the pencil. One or more optical fibers made of a sharpenable material is/are arranged in the pencil casing. The optical fiber or optical fibers extends in the longitudinal direction as well and are at least partially surrounded by the material of the pencil casing. A light entry surface of the at least one optical fiber is arranged at the rear end of the pencil casing such that a light source, which is present there, can be used to inject light to said light entry surface. The light exit surface of the optical fiber exits at the forward end of the pencil casing.</p> |
