US 7,009,189 B2 · Particle detection system and method

Abstract

An apparatus and method for detecting particles. A flow tube is surrounded by eight off-axis ellipsoidal mirrors all having a common first focus coincident with a portion of the flow tube and each having a distinct second focus. In one embodiment, sources of radiation are arranged coincident with exit ports in the mirrors that are also coincident with the respective distinct second foci. These radiation sources are momentarily energized in sequence (or simultaneously), causing light to illuminate a corresponding ellipsoidal mirror. This light strikes the common first focus within a portion of the flow tube. Any particles within the first focus will then scatter the light, and depending upon the source wavelength and the particle, may also provide some amount of fluorescence. This energy is captured by detectors and analyzed to determine the type, size and quantity of particles at the first focus.

Claims22

Dependent claims

An apparatus for detecting particles, comprising:

a passage through which particles to be detected travel;
a detector assembly through which the passage passes;
and
an analyzer in communication with the detector assembly,
the detector assembly comprising a waveguide that receives light emitted or scattered by the particles and at least two bandpass filters disposed inline with the waveguide;
at least two photodetectors, respectively arranged to detect light passing though each of the bandpass filters;
an ultraviolet (UV) light source for illuminating the particles;
and
a UV light transmitting mirror that allows UV light to reach the passage.

6 more elements

Dependencies are inferred from the claim text.

Particle detection system and method

Life of this patent

Particle detection system and method

Life of this patent

Abstract

Claims22