Identification system for bodies containing luminous material - uses intensity-wavelength distribution in emission spectrum for testing

摘要

The identification system for bodies containing luminous or fluorescent material uses an induction radiation source for directing this onto a body in the testing station. The luminous material is induced to emit light radiation which in the event of different wave lengths is picked up at the same time by numerous optical systems (24, 25, 26) and passed to relevant photodetectors (18, 19, 20). Each optical system is associated with an optical filter (21, 22, 23) so as to transfer to the associated photodetector a different selected wavelength or range of wavelengths from those wavelengths which are sent to a different photodetector. Each photodetector produces an output signal which linearly changes its level according to the intensity of the emitted light ray which falls on this. The signal level of a photodetector is altered by attenuation or amplification and the altered signal level is compared with the signal level derived from a different photodetector.