RECENT ADVANCES OF VACUUM METROLOGY TECHNIQUES AND APPLICATIONS WITH OPTICAL METHODS

The research and development works with optical methods are considered to be one emerging area in the field of vacuum metrology. Typical examples of these kinds of techniques for primary and secondary standards are presented, such as the fixed-length, Fabry-Pérot optical cavity for the rough vacuum regime, Tunable Diode Laser Absorption Spectroscopy(TDLAS) for its use as a primary standard for partial pressure measurement, dynamic vacuum calibration with Michelson interferometer and determination of the gas micro-flow by the optical interferometric technique. It can be convinced that the measurement uncertainties of the current vacuum standards will be reduced substantially by the optical methods. At the same time, the future of vacuum measurement will rely on quantum-based primary standard which represents a disruptive change in the way of realizing and disseminating the SI unit of pressure, the pascal.