| 摘要 |
The invention relates to methods and devices for testing the colour fastness of objects, such as bank notes, security, identification or value documents for instance, by measuring the light that is issued from an object to be verified and is especially reflected or transmitted, whereby said objects are imprinted with security printing colour. The aim of the invention is to guarantee a particularly reliable colour fastness test. The light that is issued from the object to be verified is detected in spectral regions which are situated outside a visible spectral region. The aim of the invention is also to obtain a user-friendly and secure colour fastness test. The light that is issued from the object is detected in several points of the object and in at least two selected spectral regions and a series of measurements is produced for each spectral region respectively. Two series of measurements are adapted to each other and the colour fastness test is subsequently carried out by comparing the two series of measurements, which are adapted to each other. A particularly compact and user-friendly device which is easy to adjust is characterised in that at least one screen is provided between the object and the detector for adjusting the size of the area that is to be tested on the object.
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