| 摘要 |
<p>PURPOSE:To prevent the damage of ends of an optical fiber, by providing a projection projected from the ends with a plane opened with the ends of an optical fiber opposing to a recording medium. CONSTITUTION:Ends of optical fiber bundles 4, 5 at light projection and reception side are opened at a card contact surface 10 of a case 1. Near the optical fiber end on a card contact surface 10, a spacer 9 made of material having hard quality and wear resistance is fixed. The spacer 9 is projected from the surface 10 by minute height DELTAL. This minute gap DELTAL is decided within a range kept for the accuracy for mark read-in. Through the gap DELTAL, foreign matter 13 such as sand stuck on a card 6 for the surface of the card 6 are not allowed to contact with the ends of the optical fiber bundles 4, 5, allowing to prevent wear of the end of optical fiber.</p> |
