Detection of chemicals
Abstract
Abstract A device for detecting the presence of a chemical material, such as a gas, amongst a number of incident chemical materials comprises a group of sensors (1,2,3) having overlapping broadband selectivities in respect of the incident materials, so that each sensor responds, to a greater or smaller extent, to each of the materials. The sensor outputs are fed to a signal processor (5) which produces, for each material, a notional vector. These vectors are compared with stored reference vectors to identify the material under investigation. The responses to the various materials have a time-varying portion (x,y,z) and a portion of constant value. Certain materials may produce the same constant value, but different time-varying portions. The latter portions are therefore also taken into account in identifying the materials. A chromatographic layer may be provided over the sensors to distinguish between chemical species in the materials under test. <IMAGE>
Inventors
- 👤 Donald J. Weir
Bibliographic Details
Claims Analysis
Total Claims: 7References Cited (Backward Citations)
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| 7.5 Years (Year 8) | 2000-08-23 | 2001-02-22 | 2001-08-24 | $3760.00 | Window Closed / Lapsed |
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