The sector's activities aim to improve knowledge and develop instruments and methods in length metrology applied to the research world, the industry world, and space research.

The sector is organised into the following projects

• Dimensional metrology and the Standard of the Metre
• Nano-metrology and surface metrology
• Coordinate metrology and long distances
• Combined optical and X-ray interferometry (COXI)
• The realisation of the kilogram through the Planck constant
• Metrology for space missions.