| 摘要 |
PURPOSE:To improve efficiency of detecting level for a member to be detected, by enabling a light, emitted from a light-emitting section and reflected upon the objective member, to be converged into a light-receiving section with a directivity. CONSTITUTION:A material 3 to be detected, such as a sheet-like manuscript, is fed into a conveying passage 13 from an entering section 11, and it is conveyed between inner and outer arcuate guiding members 4 and 6 by an entry-side feeding roller 9. Before the member 3 enters an opening section 5 for detection, a light emitted from a light-emitting section 1 is absorbed by a non-reflective disposing section 7 and does not reach a light-receiving section 2. When the member 3 entered the opening section 5 and was bent into an arch-like shape, the light emitted from the light-emitting section 1 is reflected upon the arch-like surface of the member 3 to be turned into a light having been converged with a directivity and reaches a light-receiving section 2 allowing existence of the member 3 to be detected. When the member 3 was carried over to an exit 12 by an exit feeding roller 10 and therefore the opening section 5 became devoid of the member 3, the light from the light-emitting section 1 is made unable to reach the light-receiving section 2. |
