| 摘要 |
PURPOSE:To carry out detection accurately and rapidly, by providing an absorbing cell through which a liquid containing a component to be measured is flowed, light emitting parts for emitting two kinds of colors, a light receiving part, a change-over switch and an integrator are provided so as to obtain a pulse width signal corresponding to the concn. of the component to be measured. CONSTITUTION:When the output of a comparator 14 is made low by the output of an integrator consisting of a capacitor C1 and an operation amplifier 13, change-over switches 5-7 are connected to the upper side and, when said output is made high, they are connected to the lower side. In addition, light emitting elements 8, 9 having green light and red light are alternately operated to emitt lights and, after said lights transmit through an absorbing cell (not shown in drawing), output corresponding to the concn. of a component to be measured is generated from a light receiving element 10 while said lights are permitted to alternately pass points (c), (b) to output a pulse width signal from the comparator 14 through an integrator. In this case, an integration of VG for time t is equal to an integration of VR for time T-t, and the ratio of (t) or (T-t) relative to T corresponds to the concn. of a component to be measured. |
