| 摘要 |
PROBLEM TO BE SOLVED: To provide a mirror surface cooling type dew point meter which requires no cleaning of a mirror surface by manpower, requires no separately provided apparatus for removing condensed materials, and shortens interruption of dew point temperature measurement.SOLUTION: After control such that supply power to a thermoelectric cooling element becomes in an equilibrium state is interrupted (step S601), it is determined whether a state of a mirror surface is normal or abnormal (steps S602-S604). When it is determined that the state of the mirror surface is abnormal (the step S604), a gate valve is closed and a suction pump continues to be driven (step S606). Accordingly, pressure in a sampling chamber is reduced, and, when a condensed material adheres to the mirror surface, the condensed material vapors or sublimes at a high speed to be removed. Regardless of whether the state of the mirror surface is normal or abnormal, pressure in the sampling chamber may be reduced, in response to operator's instruction or periodically. |
