METHOD AND DEVICE FOR VERIFYING THE TRANSMITTANCE OF A FLAT GLASS SUBSTRATE

The invention relates to a method and an associated device for verifying the transmittance of a flat-glass substrate (40) with a measuring device (10), with which light of at least one light source (20) is guided from one side of the flat-glass substrate (40) through the flat-glass substrate (40) to the opposite side of the flat-glass substrate (40), where it is captured by at least one receiving unit (30) and the transmittance of the flat-glass substrate (40) is determined by means of a comparison between the intensity of the light emitted by the light source (20) and the light incident upon the receiving unit (30). In a first measurement, a light source (20) generates polychromatic light in the process, wherein the transmittance is determined at a point of the flat-glass substrate (40), and in at least one further measurement, a light source (20) generates monochromatic light of a defined wavelength, the transmittance also being determined at the same point of the flat-glass substrate (40), if possible. By comparing the at least two measurements, it is determined whether the transmittance is approximately the same or not the same in all measurements, in order thus to be able to better narrow down the cause for a reduced transmittance.