| 摘要 |
PROBLEM TO BE SOLVED: To stably detect a conveyance object such as a circuit board to be conveyed by a conveyor.SOLUTION: A light projection section 14 is constituted so that upward and downward width of a detection area for projecting light to a passage area of a circuit board 11 conveyed by a conveyor covers upward and downward width of the passage area of the circuit board 11. A light reception section 17 is provided with split light reception sections 1, 2,..., n independently for each split detection area obtained by splitting the detection area into plural split detection areas in an upward and downward direction, and detection sections 21, 22,..., 2n for detecting light reception amounts respectively are provided to the respective split light reception parts 1, 2,..., n. Light reception amounts A1, A2,...,An detected by the detection sections 21, 22,..., 2n of the respective split light reception parts 1, 2,..., n are monitored. When reduction of the light reception amount of any split light reception part is detected, detection of the circuit board 11 is determined. |
