| 摘要 |
PURPOSE:To perform sensitivity correction at high speed and high accuracy by digitally controlling the lighting time of a light source based on standard sample measurement values via memory, shift register, etc. to which the addresses corresponding to scanning wavelength light are written. CONSTITUTION:Writing in the addresses corresponding to the waelengths of scanning write is accomplished in the memory M of a correction circuit C during outputting of the scanning light through a read-write control circuit LR cooperating with the wavelength scanning of a spectroscope 1, and the bits of a shift register SR are shifted at every wavelength scanning of the spectroscope 1. The shift output of said register SR controls the lighting time of a light source 10 such as light emitting diode, etc. via latch circuit Ra, D/A converter DA. On the other hand, writing of the memory M by the circuit LR is accomplished by the output of a comparator 18 only when the measurement integrated value from the light source 10 is smaller than that of the specstroscope 1 at the measuring of a white standard smple 6 of flat spectral reflection characteristics, and the addition time is added according to the shift bits of the register SR, whereby the lighting time of the light source 10 is controlled. Hence, highly accurate sensitivity correction is completed within a short time of one scanning period of the spectroscope. |
