Measuring data extracting from PbS detector signal in the NIR moisture meter
Mirko Filić, Venco Ćorluka · 2006
The reflectance at two, absorbing and not absorbing wavelengths in the near infrared (NIR) region from several wheat grain samples with different moisture content detected by the precise gravimetric instrument, has been measured. The periodical measuring signal given by the photoconductive PbS detector and amplified with a band pass analogue preamplifier cosists of both, beneficial and unfit information. The input radiation was assigned by the mechanical chopper with adequate optical filters and directed to the sample by the input and amplified output has been conducted by using the Fast Fourier transformation (FFT). The applied approach with all calculation and measurement results are presented in this paper.