Methods and devices for the detection of odorous substances and applications

• US 5,918,257 A
• Filed: 01/22/1998
• Issued: 06/29/1999
• Est. Priority Date: 09/17/1993
• Status: Expired due to Term

• Current Assignee: Alpha M.O.S.
• Original Assignee: Alpha M.O.S.
• Inventors: Moy, Laurent, Mifsud, Jean Christophe
• Primary Examiner(s): LARKIN, DANIEL SEAN
• Application Number:
  US09/010,705
• Time in Patent Office: 523 Days
• Field of Search: 73/23.34, 73/31.01, 73/31.02, 73/31.03, 73/31.05, 73/31.06
• US Class Current: 73/23.34
• CPC Class Codes: G01N 33/0031 comprising two or more sensors, e.g. a sensor array
• CPC Class Codes: G01N 33/14 Beverages

Abstract

Device for carrying out a method of odor detection comprising, in particular, a plurality of chambers, each including a plurality of semiconductor gas sensors, conductive polymer gas sensors, and surface acoustic wave gas sensors, as detection devices, a variable flow gas pump for forming a gas flow in said chambers, measurement electronic device for operating the detection devices, a data processing unit for recording in a file the olfactory prints obtained using the detection means, and for comparing the detected impressions with those in the file so that odors may be identified and recognized. Applications exist, especially to drugs, explosives, body odors and food seals.

Claims

1. A process for analyzing odorous or volatile substances using an apparatus including;

a first enclosure having a first detection means, said first detection means comprising a plurality of gas sensors using a same first technology selected from semiconductor gas sensor technology, conductive polymer gas sensor technology, or surface acoustic wave gas sensor technology,

a second enclosure having a second detection means, said second detection means comprising a plurality of gas sensors using a same second technology selected from semiconductor gas sensor technology, conductive polymer gas sensor technology, or surface acoustic wave gas sensor technology, said second technology being different from said first technology,

said semiconductor gas sensors, conductive polymer gas sensors and surface acoustic wave sensors having electrical or piezoelectric properties sensitive to molecules of the odorous or volatile substances, said process comprising the steps of;

determining electrical or piezoelectric properties of the first and second detection means by contacting the first and second detection means with a variable gas discharge to initialize the first and second detection means;

transporting the odorous or volatile substances of a first sample to the first and second enclosures by a variable controlled gas discharge;

measuring electrical or piezoelectric properties of the first and second detection means, during a determined measurement time interval, in the presence of a variable controlled gas discharge containing the odorous or volatile substances of the first sample, wherein relative to the electrical or piezoelectric properties during initialization, to obtain qualitative data and quantitative data for the odorous or volatile substances of the first sample;

comparing said qualitative data of the first sample with a file of odorous or volatile substances, simultaneously with the step of measuring or after the step of measuring, the comparison occurring during the measurement time interval, to identify or recognize the odorous or volatile of substances of the first samples; and

cleaning the first and second detection means with a gas, in order to re-initialize the first and second detection means.

2. A process according to claim 1, characterized in that said apparatus includes at least a third enclosure having a third detection means, said third detection means comprising a plurality of gas sensors using a same third technology selected among semiconductor gas sensor technology, conductive polymer gas sensor technology, or surface acoustic wave gas sensor technology, said third technology being different from said first and second technologies.

3. A process according to claim 2, wherein said first, second, and third enclosures are arranged in series.

4. A process according to claim 2, wherein said first, second, and third enclosures are arranged in parallel.

5. A process according to claim 1, wherein said first and second enclosures are arranged in series.

6. A process according to claim 1, wherein said first and second enclosures are arranged in parallel.

7. A process according to claim 1, wherein the odorous or volatile substances are separated by means of a gas chromatography device.

8. A process according to claim 1, wherein the odorous or volatile substances are analyzed to detect or recognize drugs and/or explosives.

9. A process according to claim 1, wherein the odorous or volatile substances are perfumes and/or cosmetics, and are analyzed to evaluate the sensory characteristics of the perfumes and/or cosmetics.

10. A process according to claim 1, wherein said first technology is semiconductor gas sensor technology and said second technology is conductive polymer gas sensor technology.

11. A process according to claim 1, wherein said first technology is semiconductor gas sensor technology and said second technology is surface acoustic wave gas sensor technology.

12. An apparatus for analyzing odorous or volatile substances, comprising:

a first enclosure including a first detection means having electrical and/or piezoelectric properties sensitive to molecules of the odorous or volatile substances, said first detection means comprising a plurality of gas sensors using a same first technology selected from semiconductor gas sensor technology, conductive polymer gas sensor technology, or surface acoustic wave gas sensor technology;

a second enclosure including a second detection means having electrical and/or piezoelectric properties sensitive to molecules of the odorous or volatile substances, said second detection means comprising a plurality of gas sensors using a same second technology selected among semiconductor gas sensor technology, conductive polymer gas sensor technology, or surface acoustic wave gas sensor technology, said second technology being different from said first technology;

pump means for variably discharging a gas;

means for testing and measuring the electrical and/or piezoelectric properties of said first and second sensing means to obtain qualitative and quantitative data on the odorous or volatile substances; and

means for comparing the qualitative data with a file of odorous or volatile substances, to identify or recognize the odorous or volatile substances.

13. An apparatus according to claim 12, further comprising at least a third enclosure, said third enclosure including a third detection means, said third detection means comprising a plurality of gas sensors using a same third technology selected from semiconductor gas sensor technology, conductive polymer gas sensor technology, or surface acoustic wave gas sensor technology, said third technology being different from said first and second technologies.

14. An apparatus according to claim 12, wherein means for comparing the qualitative data with a file of odorous or volatile substances, to identify or recognize the odorous or volatile substances, is a neural network.