Coulter Electronics, Inc.

Mack J Fulwyler

C William Hatcher

Uniform particles are produced by introducing a laminar stream of a core liquid into a laminar flowing body of an immiscible sheath liquid. The core liquid or the sheath liquid, or both liquids, can contain one or more materials dispersed (dissolved or suspended) in them from which the uniform particles are formed. The two liquids and the dispersed material are expelled from a nozzle to form a liquid jet. The liquid jet is disturbed at a uniform, periodic rate to form liquid droplets which contain a uniform amount of the core liquid, the sheath liquid and the dispersed material. The droplets are collected and held in a catch liquid until the core and the sheath liquid in each droplet have diffused into the catch liquid leaving the uniform particles formed from the dispersed materials. There can be more than one sheath liquid which can also contain one or more materials dispersed in it.

Droplet forming apparatus for use in producing uniform particles

A method and apparatus for forming a separate single drop wherein a fluid stream is formed in air and an electrical charge or radiant energy is applied to the stream at a particular location in order to disturb the stream and create a single drop. The drop may be formed surrounding a particle and the drop may be charged when formed, then deflected for separate collection.

Single drop separator

Method for producing uniform particles

A background light filter for use in an optical particle analysis system operates to attenuate light coupled thereto and pass an attenuated intensity light signal. If the light coupled to the filter takes the form of discrete beams or areas forming a pattern, the filter will selectively attenuate in only those portions of the filter struck by the light beams forming the pattern. The optical filter is substantially insensitive to short term variations in light coupled thereto so that changes in the received light pattern which may, for example, be produced by passage of a particle through the light beam producing the pattern, will be passed through the optical filter with substantially no attenuation.

Particle analysis system with photochromic filter

An optical chamber for use in an apparatus for measuring characteristics of small particles such as blood cells while the particles are suspended in a liquid includes a housing which defines the optical chamber. An entrance and exit are formed in the chamber for allowing entry and exit of the particle suspending liquid. The chamber itself is formed to allow passage of the particle suspending liquid therethrough in a thin stream with the particles in the stream passing through the chamber in sequence. A portion of the housing is formed from light transmitting material for allowing a beam of light to be transmitted into the chamber where it intersects the thin stream of particle suspending liquid at a junction point and produces resultant light upon intersecting said particles. A spherical shaped portion is formed in the housing and is concave into the chamber with the radial center of the spherical shaped portion located substantially at the junction point. The concave surface is reflective to reflect the resultant light coupled thereto. An apparatus including the optical chamber is also disclosed.

Growing community of inventors

Los Alamos, NM, United States of America

Mack J Fulwyler