PURPOSE: To make it possible to correctly detect the border surface of double-layer liquid by causing the tip of an optical fiber to enter the double-layer liquid, and varying the set value of the reflected light receiving output on the basis of the output of the light receiving element when the tip of the optical fiber has entered the upper layer of the double-layer liquid.
CONSTITUTION: An optical probe comprises a projecting element 22, a receiving element 23, and an optical fiber 21, one-ends of which are introduced to the projecting element and receiving element. Another end of the optical fiber 21 is caused to enter the double-layer liquid such as blood specimen or the like, and the output of the light receiving element 23 when the above described another end has advanced in the upper layer of the double-layer liquid is set as an initial value, the set value of the output of the receiving element 23 due to the reflected light on the border surface BK of the double-layer liquid. By this procedure, even when an outer disturbance factor absorbing or reflecting the reflected light from the optical fiber exists in the upper layer of the double-layer liquid, the border surface of the double- layer liquid can be detected correctly.
KONUMA FUMIO
KIMURA SHIYOUJI
| JPS53132391U | 1978-10-20 |