# US 10,309,898 B2 · Particle detection > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,309,898 B2 - Document ID: US10309898B2 - Status: Granted - Kind: B2 - Application number: 15/456,246 - Filed: 2017-03-10 - Published: 2017-06-29 - Granted: 2019-06-04 - Earliest claimed: 2008-06-10 - Assignees: Garrett Thermal Systems Limited - Applicants: Garrett Thermal Systems Limited - Inventors: Ronald Knox; Kate Cooper; Kemal Ajay - Web page: https://patentgrep.com/patent/US10309898B2 ## CPC - G01N 21/53: within a flowing fluid, e.g. smoke - G01N 15/0205: by optical means - G01N 15/0227: using imaging; using holography - G01N 15/1434: Optical arrangements - G01N 21/49: within a body or fluid - G01N 21/538: {for determining atmospheric attenuation and visibility} - G08B 17/107: for detecting light-scattering due to smoke - G01N 2201/0621: Supply - G01N 2201/0696: Pulsed - G08B 17/113: Constructional details - G01N: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES (measuring or testing apparatus or processes other than immunoassay, involving enzymes or microorganisms C12M, C12Q) - G08B: SIGNALLING SYSTEMS, e.g. PERSONAL CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS ## Abstract A particle detection system including; at least one light source adapted to illuminate a volume being monitored at at least two wavelengths; a receiver having a field of view and being adapted to receive light from at least one light source after said light has traversed the volume being monitored and being adapted to generate signals indicative of the intensity of light received at regions within the field of view of the receiver; a processor associated with the receiver adapted to process the signals generated by the receiver to correlate light received at at least two wavelengths in corresponding regions within the field of view of the receiver and generate an output indicative of the relative level of light received at the two wavelengths. ## Claims ### Claim 1 A receiver for a particle detection system, the receiver including: a light sensor having field of view and being capable of distinguishing light received from a plurality of regions within the field of view and determining a level of light received at each of two or more wavelengths in each of said regions; and a processor adapted to receive, from the light sensor, data representing received light and to identify a region of the plurality of regions in which said light is received and to generate a signal indicative of particles in the monitored region on the basis of a reduction in received light using the relative level of light received at said at least two wavelengths in the identified region. ### Claim 2 (depends on 1) The receiver as claimed in claim 1 wherein the processor is adapted to update said identification of the identified region from the plurality of regions over time. ### Claim 3 (depends on 1) The receiver as claimed in claim 1 wherein the light sensor includes a plurality of light sensor elements which correspond to a respective region of the field of view. ### Claim 4 (depends on 2) The receiver as claimed in claim 2 wherein the processor is adapted to identify a subset including one or more light sensor elements at which light from the light source is received. ### Claim 5 (depends on 4) The receiver as claimed in claim 4 wherein the processor processes received data in a plurality of time periods and track changes in the subset of the sensor elements corresponding to one or more light sources over time. ### Claim 6 (depends on 1) A particle detection system including a receiver as claimed in claim 1 and at least one light source for cooperating with the receiver to define at least one beam detector. ### Claim 7 (depends on 6) The particle detection system as claimed in claim 6 further including at least one other light source and defining at least one other beam detector. ### Claim 8 (depends on 7) The particle detection system as claimed in claim 7 and including a processor configured to: detect particles using the first beam detector; determine if particles are detected by at least one other beam detector; and determine the location of the detected particles on the basis of said determination and the relative positions of first the first beam detector and the at least one other beam detector. ### Claim 9 (depends on 8) The particle detection system as claimed in claim 8 wherein the at least two beam detectors are defined by two light sources cooperating with a common receiver. ### Claim 10 (depends on 8) The particle detection system as claimed in claim 8 wherein in the event that particles are also detected by the at least one other beam detector the location of the particles is determined to be a region monitored by both beam detectors. ### Claim 11 (depends on 8) The particle detection system as claimed in claim 8 wherein in the event that particles are not detected by the other beam detectors, the location of the particles is determined to be a region monitored by the first beam detector but not the other beam detectors. ### Claim 12 (depends on 8) The particle detection system as claimed in claim 8 wherein the beam detectors are arranged such that at a plurality of locations in the region being monitored by the system are monitored by at least two beam detectors. ### Claim 13 (depends on 8) The particle detection system as claimed in claim 8 wherein the particle detection system includes beam detectors having beam paths that are arranged next to each other such that their lengths overlap to enable a location of particle detection, along the length of the beam of the first detector, to be determined.