BG105117A - Photometer - Google Patents

Abstract

The photometer is used for measuring of absorption and luminescence. It has improved reliability and better signal/noise ratio, wide range of measuring the intensity of light, reduced power consumption, high efficiency and improved heat exchange. The photometer comprises a luminaire (1), connected across first filter (2) and pattern (1) to first photoreceiver (4) where pattern (0) is also optically connected by a second filter (3) to a second photoreceiver (5). The photometer comprises a generator (6), coupled to voltage-controlled source of light (7) and by means of a synchronous detector (8) - to a low frequency filter (9). Each photoreceiver comprises a photodiode (10 and 11) and transimpedance amplifier (12 and 13), wherein photoreceivers (4 and 5) are connected in parallel across switch (K) to the input of a high frequency filter (16), which is connected across amplifier/attenuator (14) to the synchronous detector (8), and the current source (7) is connected to the luminaire (1) which contain n-number of light emitting diodes (C1-Cn), optically connected across the respective optical filters ("1-"n) to an optical unit (15) for forming a light spot on the pattern with a 1-2 mm diameter. 6 claims, 4 figures