Photoacoustic sensor with replacement gas and detection process using such a sensor

US11555780B2 · kind B2 · utility

Assignee

• DRÄGERWERK AG & CO. KGAA · DE

Inventors

• Ralf Buchtal · Lübeck, DE
• Gerd Peter · Lübeck, DE
• Bernd-Michael DICKS · Damlos, DE
• Björn Spilker · Lübeck, DE
• Robert JAHNS · Lübeck, DE
• Martin KROH · Lübeck, DE

Key dates

• Filing date: Jul 20, 2021
• Grant date: Jan 17, 2023
• Expiry date: Aug 2, 2041

Classification

• Technology area (CPC G): Physics
• CPC primary: G01N2021/1704
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A photoacoustic sensor (100) is capable of detecting a predefined target gas in an area (Um). A process is capable of detecting the target gas with the use of such a sensor (100). A sample chamber (3) holds a gas sample (Gp) to be tested. Electromagnetic waves (eW) from a radiation source (1) pass through the sample chamber (3) and the detection chamber (4). The waves elicit in the detection chamber (4) an acoustic effect, which is measured by an acoustic sensor (7). The acoustic effect is correlated with the concentration of the target gas in the sample chamber (3). The detection chamber (4) is fluid-tightly sealed, is free from target gas and is filled with a replacement gas (Eg). The transmission of the replacement gas (Eg) has a spectral response similar to that of the transmission of the target gas in a predefined target gas wavelength range.