JPS5679238A - Detector for trace of blood - Google Patents

Abstract

PURPOSE:To accurately measure the leakage quantity of blood by allowing two light-emitting members to intermittently emit light with different periods, receiving the light passing through a tube for passing a liquid therethrough by means of a light-receiving member, and separating the light into those corresponding to the light-emitting members to compare one with another. CONSTITUTION:A light-emitting element 12 emits light having a wavelength absorbed by blood, while a light-emitting element 13 emits light having a wavelength not absorbed by blood. These lights are received by a light-receiving element 17 through a dialytic-solution exhaust tube and the dialytic solution. The output of the light-receiving element 17 is added through an amplifier 18 to detectors 19 and 20, from which two signals corresponding to intermittent lights from the light- emitting elements 12 and 13 respectively are obtained. These two signals are inputted to an operational amplifier 21 to detect the difference between the two signals. From the difference, the quantity of blood contained in the dialytic solution is detected.