| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a substrate detector, capable of detecting a light- transmittable substrate accurately over a long period of time. <P>SOLUTION: In a substrate detector, detecting that a glass substrate 1 has reached the predetermined location in the vicinity of an inlet and outlet for conveyance (7 and 8) outside a heat treatment furnace by a reflective photoelectric switch 4, a nozzle 5 blow out cleaned air (clean dry air) is provided, in such a manner such that it blows out through the part on the light-projecting/ receiving part 4a of the photoelectric switch 4. <P>COPYRIGHT: (C)2003,JPO</p> |
