Title:
粒子検出器
Document Type and Number:
Japanese Patent JP4750705
Kind Code:
B2
Abstract:
A smoke detector (10) is disclosed which uses a beam of radiation such as a laser (16), to monitor a region, such a room (12). A camera (14) is used to capture images of part of the room (12), including a path of the laser beam. Particles in the laser beam scatter light (30), and this is captured by the camera (14) for analysis. A processor (20) extracts data relating to the scattered light (30) to determine the density of particles in the beam, to determine the level of smoke in the region. The laser may have a modulated output (38) so that images captured without the laser can be used as a reference point and compared to images taken with the laser on, to assist in determining the level of scattered light (30) compared to ambient light. Filters (24, 26) may be used to decrease signals generated from background light.
Inventors:
Ron Knox
Karl Bettger
Peter Mickle
Brian alexander
Karl Bettger
Peter Mickle
Brian alexander
Application Number:
JP2006529439A
Publication Date:
August 17, 2011
Filing Date:
May 14, 2004
Export Citation:
Assignee:
BFS Technologies Limited
International Classes:
G01N15/02; G01N15/06; G01S17/89; G08B17/10; G08B17/103; G08B17/107
Domestic Patent References:
| JPH0520563A | 1993-01-29 | |||
| JPH0712724A | 1995-01-17 | |||
| JPH10154284A | 1998-06-09 | |||
| JPH11339150A | 1999-12-10 | |||
| JPS62197745A | 1987-09-01 | |||
| JPH0546878A | 1993-02-26 | |||
| JP2003099876A | 2003-04-04 |
Foreign References:
| US5696379A | 1997-12-09 | |||
| US3924252A | 1975-12-02 |
Attorney, Agent or Firm:
Takuji Yamada
Mitsuo Tanaka
Mikio Takeuchi
Mitsuo Tanaka
Mikio Takeuchi