| 摘要 |
PURPOSE:To make possible taking of plural signals with one AD converter by making the times of the AD conversion of zero signal less than the normal times, leading another signal to the AD converter with an analog switch in place, and taking this in a processing unit. CONSTITUTION:Luminous flux LB of single light color from a spectroscope is divided to a reference side luminous flux RB and sample side luminous flux SB by a chopper 1. After both luminous fluxes pass through respective samples 14, 15, they are combined to one luminous flux by a half mirror 6. The luminous flux is then converted to an electric signal in a photoelectric transducer 7. The signal is converted to a digital signal in an AD converter 9 through an amplifier 8 and analog switch 21 and is taken in a processing unit 10. At this time, the signals from the photoelectric transducer 7 and temperature detector 11 are alternately led to the AD converter 9 by dividing the timing signal TS3 for zero signal out of 3 kinds of timing signals from a timing generator 3 to two kinds of timing signals TS31, TS32 by a pulse divider 22 and at the same time changing over the analog switch 21 by one of said signals. |
