Physikalisch-Technische Bundesanstalt

Tasks

• Precision Interferometer
• High accuracy determination of thermal expansion coefficients and compressibility
• Investigation of the homogeneity of thermal expansion
• Investigation of length relaxation and long term stability

• Gas-Refractometry
• High accuracy determination of the air refractive index as a function of environmental parameters using refractometer cells
• Ultra high determination of air constituents using the "length refractometer"

• Further development of gauge block comparators
• Example: conversion of the PTB Kösters-Comparator to phase stepping interferometry