Abstract: A detector assembly for analysis of light emitted form a fluorescent material, an optical alignment assembly for introducing an output beam into a detector array or demultiplexer, and methods of demultiplexing a beam of light into wavelength bands. The detector assembly generally includes an optical alignment assembly to introduce an output beam having a projected optical axis into an array of filters. The optical alignment assembly is mounted substantially orthogonally to a plane of reflective light defined by the path of the output beam through the filter array. The array includes filters arranged in two rows in parallel. Each filter transmits a particular band of the output beam and reflects the remaining bands to the next filter in the opposite row of filters. The array further includes a plurality of detectors mounted in detector ports.

Abstract: A method and apparatus for selectively sorting individual particles, such as blood cells of a particular type of interest, from a plurality of particles of different types. Particles of interest are individually differentiated from other particles in a known manner, and a discrete control signal is produced in response to having identified a particle of interest. An impulse generator, acting in response to such control signal, applies a focused impulsive force on the identified particle of interest, such force serving to eject such particle from the plurality of particles of which it is a part. The ejected particles of interested are then collected in a separate container. The apparatus of the invention is preferably embodied in a flow cytometric instrument.

Abstract: A method and apparatus for selectively sorting individual particles, such as blood cells of a particular type of interest, from a plurality of particles of different types. Particles of interest are individually differentiated from other particles in a known manner, and a discrete control signal is produced in response to having identified a particle of interest. An impulse generator, acting in response to such control signal, applies a focused impulsive force on the identified particle of interest, such force serving to eject such particle from the plurality of particles of which it is a part. The ejected particles of interested are then collected in a separate container. The apparatus of the invention is preferably embodied in a flow cytometric instrument.

Abstract: A droplet travel path monitoring mechanism for a flow cytometer is operative to adjust the droplet break-off point back to an initially calibrated spatial location, in the event of the departure from calibrated timing of gaps in the unsorted fluid droplet stream that have been created by the deflection of charged droplets. In addition, the flow cytometer is operative to monitor prescribed characteristics of deflected droplet streams, and to controllably adjust drop-sorting deflection parameters, so as to maintain the deflected travel path of sorted droplets coincident with the opening into a sorted droplet collection container, thereby maximizing collection of all sorted droplets.