OPTICAL DETECTOR

摘要

OPTICAL DETECTOR The optical detector is particularly adapted for use with an apparatus for separating blood into its components and is of the type including a centrifuge for centrifuging whole blood to separate same into the components thereof and of the type wherein plasma is withdrawn from the centrifuge through a flexible, light transmitting tubing and the spillover of red blood cells into the plasma withdrawn is monitored by the optical detector. The optical detector comprises a block having a slot across the top face thereof, the inner portion of the slot having a width less than the outer diameter of the tubing which is received in the slot such that when the tubing is pressed into the slot, it is squeezed from a circular cross section to an oval cross section to present two flat portions of the tubing adjacent opposite sidewalls of the slot. A first cavity is situated in the block behind a first sidewall of the slot and a second cavity is situated in the block behind a second sidewall of the slot. Apertures are provided in the sidewalls and light from a light source is directed along the axis of the apertures, through lenses in the cavities which seal the cavities from the slot and through the tubing in the slot from the first cavity to the second cavity where a photosensor is located. The photosensor is operable to generate an electrical signal which is indicative of the light sensed and which can be utilized for measuring the optical density of the plasma flowing through the tubing.