| 摘要 |
<p>The invention relates to a spectral sensor for inspecting value documents, said sensor having an illumination device for illuminating the value document, imaging optics and a detection device. The illumination device contains a plurality of light sources with emission spectra that differ from one another, said sources being switched on and off in succession, in order to illuminate a region of the value document with an illumination sequence consisting of light pulses with different emission spectra. One measured value is detected for each of the light pulses in order to record the spectral intensity distribution of the detected light. The plurality of light sources cover a section of the near infra-red spectral range and/or a section of the visible spectral range in such a way that the spectral sensor can record a spectral intensity distribution in the section of the near infra-red spectral range and/or in the section of the visible spectral range.</p> |
