| 摘要 |
PROBLEM TO BE SOLVED: To provide a substrate detecting device capable of detecting a jumping out of a substrate stored in a cassette with a minimum number of sensors. SOLUTION: The substrate detecting device that detects substrates W stored horizontally in the cassette in multiple vertical stages includes sensor supports 6a, 6b, first sensors 9a, 9b disposed on the sensor supports so as to have axes horizontally, second sensors 9c, 9d installed on the sensor supports to have optical axes inclined at a certain angle from the horizontal, and a sensor support driving means 5 of moving the sensor supports in front-rear and up-down directions with respect to a peripheral edge of the substrate W. The optical axes of the first and the second sensors are moved up and down to block the optical axes H, S by the substrate W, thereby detecting at least whether the substrate is present, the slanting state of the substrate, and the substrate jumping out on the basis of the interval at which the optical axes of the first and the second sensors are blocked. COPYRIGHT: (C)2010,JPO&INPIT |
