The opinion of the court was delivered by: WILLIAM C. CONNER
This action alleging infringement by defendant of two United States patents owned by plaintiff and covering apparatus and methods for photoanalysis of small particles such as blood cells entrained in a thin stream of liquid is before the Court on defendant's motion for summary judgment on the ground of noninfringement. For the reasons stated below, the motion is denied.
The two patents in suit are U.S. Patent No. 3,705,771 issued December 12, 1972 on Photoanalysis Apparatus ("the '771 patent") and U.S. Patent No. 3,785,735 issued January 15, 1974 on Photoanalysis Method ("the '735 patent"). Both derive from the same original application, Serial No. 2,750, filed January 14, 1970 in the names of three inventors, Mitchell Friedman, Louis A. Kamentsky and Isaac Klinger. On January 19, 1972, that application was divided, with the apparatus claims being retained in the original application and a divisional application Serial No. 219,187 being filed containing the method claims. Both patents in suit have expired so that this action is for damages only.
The specification and drawings of the two patents, which are respectively identical, describe and show an apparatus for focusing a beam of light from a source, such as a heliumneon laser, on the liquid containing the particles, such as blood cells, to be analyzed, said liquid flowing within the cylindrical bore of a glass tube oriented perpendicularly to the axis of the beam. The bore of the glass tube is of such fine diameter as to permit the particles to cross the beam axis only one at a time and the light beam is focused in an area so fine as to illuminate only one particle at a time. Depending upon certain characteristics of the particles, for example, whether they are white or red blood cells, whether they are living or dead, and how they react to certain dyes, they selectively absorb the incident light or refract or scatter it to different angles from the beam axis. The light transmitted through or from the particles is simultaneously detected by several photoresponsive devices, each including a lens and a photovoltaic cell, respectively arranged to receive light at different angular positions relative to the beam axis. Analysis of the output of these detectors permits a determination of the characteristics of the particles.
The '771 patent contains 38 claims, of which only Claims 1, 9, 16 and 38 are independent claims. Although Claim 9 is in most respects the broadest Claim of the patent, both parties have discussed Claim 1 as representative. It reads:
1. Apparatus for simultaneous optical measurement of several characteristics of each particle of a group of small particles such as blood cells while the particles are suspended in a liquid,
comprising a source of light
a housing comprised of a material which transmits light from said source and defining an optical chamber,
means for moving the particle suspending liquid through said housing in a thin narrow stream to convey the particles in sequence through the stream one by one,
means for directing light from said light source into one side of said housing to intersect with the thin stream of particles in a narrow beam substantially converging at the intersection with the stream of particles and operable to intersect the entire particle stream,
and at least two photoresponsive pick-up elements positioned outside the housing at different angular positions with respect to the direction of said beam when measured from the intersection of the beam with the stream of particles,
said photoresponsive pick-up elements being effective to simultaneousely detect different optical reactions of each ...