Photometer examining sample for colour, colouring, absorption reflection etc. - directs radiation from LED's onto sample with measurer intercepting reflected or transmitted light for evaluation in several spectral ranges

摘要

LEDs (2, 2') are placed on opposite sides at the top of the photometer and inclined so that their radiation impinges on the sample (5) at the base. The measurer (3) intercepts the reflected or transmitted radiation which is split into several spectral evaluation ranges. The number of light emitters corresponds to the number of spectral ranges for evaluation, their max. radiation in each case at least approx. coinciding with the centre of concn. of the wavelength of the associated evaluation range. The latter pref. lie between u.v. and i.r. ranges. Electroluminescent plates or fluorescent lamps can replace the LEDs. ADVANTAGE - Reduced equipment and loss of energy since filters are not required for splitting the radiation into several spectral ranges. Filters are only applied for special applications, esp. high selectivity requirement, to give additional correction.