Method for quantitative measurement of inhomogeneities of density in glasses, in particular optical glasses

摘要

The glass samples to be tested are transirradiated by divergent alternating light in each case. The emerging alternating light is scanned in a puncti-form fashion in an imaging plane using an optoelectric transducer. The alternating frequency is filtered out of the output signal of the optoelectric transducer by a narrow-band filter. The signal amplitude is recorded and/or displayed. The optoelectric transducer can preferably be set to a predetermined working point by means of a steady light source. <IMAGE>