| 摘要 |
<p>A particle detector is designed to detect particles such as cells and blood corpuscles. The particle detector includes means for passing and recovering, through an orifice, a multilayer flow consisting of an inner layer of a conductive liquid specimen, a middle layer of conductive first sheath liquid, and an outer layer of nonconductive second sheath liquid surrounding them. A pair of electrodes disposed on opposite sides of the orifice contact the conductive liquid. A particle detecting apparatus incorporates this particle detector, and a detector circuit connected to the pair of electrodes detects a particle signal on the basis of differences in the electric impedance between the electrodes. An electric current flows from one electrode to the other electrode through the conductive liquid portions, that is, the inner layer A and middle layer B. Since the outer layer C is nonconductive, the current does not flow in it. Accordingly, the diameter of the orifice effectively is substantially the same as the diameter of the middle layer. The diameter of the middle layer. may be freely changed by varying the flow rate balance of the conductive liquids and nonconductive liquid. Accordingly, the apparent diameter of the orifice may be changed as desired.</p> |
