USE OF OPTICAL FREQUENCY STANDARDS FOR MEASUREMENTS OF DIMENSIONAL STABILITY

The dimensional stability of glass ceramic materials has been investig ated using two interferometric methods and optical frequency standards . The most sensitive method uses the specimen as the spacer of an opti cal high-finesse Fabry-Perot interferometer. It is shown experimentall y that a relative length contraction of 2 x 10(-15) s(-1) due to agein g of the material can be determined within a measurement time of 2 min . The requirements and the limitations of the method are derived on th e basis of experimental data.