Length Metrology and Calibration Systems

Abstract

One of the most sophisticated challenges for science and the high technologies engineering is the growing need to address real industrial problems rather than the ideal measurement situation and embed the traceable length metrology directly into technological processes by performing precise dynamic measurements in more demanding environments than those of calibration laboratories. This chapter will present a synopsis and analysis of literature and existing scientific and technical solutions of precision length calibration. It covers analysis of laser interferometers, line detection systems, measurement signals and algorithms, as well as measurement capabilities of state-of-the art calibration systems worldwide. The contribution also addresses a thorny issue of achieving reliable measurements and meeting contradictory requirements of accuracy and productivity of line scale calibration in non-ideal environmental conditions, under the influence of many external influencing factors. The problems will be also upon the anvil of the development of an interferometer-controlled comparator that is operated in dynamic mode and enables to trace the calibration of line scale of up to L ≤ 3.5 m long to the wavelength standard.