High Stability of Temperature Control Using Vacuum Insulated Wall for Gauge Block Measurement

Abstract

The temperature has a critical effect on long gauge block measurement by interferometry. To reduce this effect, we developed a vacuum insulated wall for long gauge block measurement system. The long gauge block chamber has the dimension of 1.2 m x 2 m. The vacuum insulating walls are mainly composed of 8-mm and 10-mm thick Aluminum plates as the chamber walls and a rotary pump. Using this technique, the vacuum insulator is treated to have the pressure of 0.9 mbar. This technique can reduce heat transfer from outside environment to the chamber due to low heat conductivity of the system. The temperature stability of the chamber had been continuously investigated using 5 Pt100 probes and their temperature stability are below 15 mK at 17 OC, 20 OC and 23 OC