| 摘要 |
PROBLEM TO BE SOLVED: To accurately measure the temperature of surface of a part which receives less influence of stray light component in a simple operation by locating a part of a minimum radiation luminousity through the measurement of radia tion luminousity distribution from the surface of molten liquid in a single crystal pull-up furnace, and measuring the temperature of the part by the use of a radiation temperature measurement means. SOLUTION: A CCD camera 21 is placed outside of an opening 19 of a single crystal pull-up furnace 10, and a wall 15 of an upper chamber reflected on the surface of molten liquid 17a is viewed in a visual field D. After a radiation luminuousity signal for every part in the visual field D is fed to a computation means, a minimum luminousity signal is selected from radiation luminousity signals, and a part A radiating the signal is detected. Outside of the opening 19 a monocolor radiation thermometer is placed, and the radiation part A is viewed in the relatively narrow visual filed D. A computation means computes and measures the temperature of the surface of molten liquid to transmit the signal to a power supply control portion. |
