Laser interferometric oil manometer in gauge mode pressure measurement

摘要

A laser interferometric oil manometer is developed for use as a national primary standard in the pressure range up to 1000Pa. The heterodyne interferometer using a Zeeman stabilized He-Ne laser was used to detect the displacement of oil surfaces which reflect the laser beam directly. A phenyl ether diffusion-pump oil (NEOVAC-SY, Matsumura Oil Co. Ltd) with low vapor pressure, suitable density and viscosity is employed as the manometer fluid.