| 摘要 |
PURPOSE:To make drift compensation of a photoelectric detector without bisecting irradiating light by storing the outputs from the photoelectric detector when no photometric cells exist in an optical path and when the cells exist therein via a moving mechanism and calculating absorbancy therefrom. CONSTITUTION:A turntable 2 to which plural photometric cells 1 are attached stops in the position where irradiating light 3 passes between the two photometric cells 1 and 1'. The output from a photomultiplier 4 which receives the irradiating light enters a control circuit 8 for voltage of a negative high voltage power source via an amplifier 5, a switch 6 and a holding circuit 7. The power source voltage is controlled by said circuit to maintain the specified output of the amplifier 5. The output V0 of the amplifier 5 is stored via an AD converter 9 into a computer 10. The switch 6 is opened by the command from the computer 10 to rotate the turntable 2 so that the cell 1 is moved into the optical path. The output of the amplifier 5 is stored via the converer 9 into the computer 10. Concn. is determined by using a calibration curve from -logVt/V0. |
