Gas analyzer including a radiation source comprising a black-body radiator with at least one through-hole and a collimator

Patent metadata

Field	Value
Publication number	US-10466174-B2
Application number	US-201615376738-A
Country	US
Kind code	B2
Filing date	Dec 13, 2016
Priority date	Dec 13, 2016
Publication date	Nov 5, 2019
Grant date	Nov 5, 2019

Abstract

A gas analyzer may include: a gas chamber configured to receive a gas to be analyzed therein, a radiation source configured to emit electromagnetic radiation into the gas chamber, the electromagnetic radiation being adapted to selectively excite gas molecules of a specific type that is to be detected in the gas received in the gas chamber, a collimator configured to collimate the electromagnetic radiation emitted by the radiation source, and a sensor configured to detect a physical quantity indicative of a degree of interaction between the electromagnetic radiation emitted by the radiation source and the gas to be analyzed.

First claim

What is claimed is:

1. A gas analyzer, comprising:
a gas chamber configured to receive a gas to be analyzed therein;
a radiation source configured to emit electromagnetic radiation into the gas chamber, wherein the electromagnetic radiation is adapted to selectively excite gas molecules of a specific type that is to be detected in the gas received in the gas chamber, wherein the radiation source comprises a black-body radiator configured as an electrically heatable body;
a collimator configured to collimate the electromagnetic radiation emitted by the radiation source, wherein the collimator comprises a concave mirror positioned on a side of the electrically heatable body opposite the gas chamber, wherein the electrically heatable body comprises at least one through-hole formed therein to allow electromagnetic radiation reflected by the concave mirror towards the gas chamber to pass therethrough;
a plate-like carrier supporting the electrically heatable body and configured to transmit electromagnetic radiation emitted by the electrically heatable body towards the concave mirror; and
a sensor configured to detect a physical quantity indicative of a degree of interaction between the electromagnetic radiation emitted by the radiation source and the gas to be analyzed.

2. The gas analyzer of claim 1 ,
wherein the collimator has an optical axis, wherein the radiation source is positioned on the optical axis.

3. The gas analyzer of claim 2 ,
wherein the optical axis intersects the collimator.

4. The gas analyzer of claim 1 ,
wherein the collimator further comprises at least one of a group comprising: a convex lens, a Bragg reflector, and a Fresnel lens.

5. The gas analyzer of claim 1 ,
wherein the concave mirror has a reflectance in the infrared and/or in the visible and/or in the ultraviolet frequency range of at least 20%, or of at least 50%, or of at least 80%.

6. The gas analyzer of claim 1 ,
wherein the collimator has at least one focal point, wherein the radiation source is positioned in a focal point of the collimator.

7. The gas analyzer of claim 1 ,
further comprising a filter configured to selectively transmit electromagnetic radiation emitted by the radiation source.

8. The gas analyzer of claim 7 ,
wherein the filter is configured as a tunable filter the transmission characteristics of which are tunable.

9. The gas analyzer of claim 8 ,
wherein the tunable filter comprises or is configured as a plasmonic filter and/or a Fabry-Pérot interferometer.

10. The gas analyzer of claim 7 ,
wherein the filter comprises or is configured as a collimator filter in physical contact with the collimator.

11. The gas analyzer of claim 10 ,
wherein the collimator filter is configured as a filter layer deposited on a surface of the collimator.

12. The gas analyzer of claim 1 ,
further comprising a source unit comprising a holder supporting the radiation source and/or the collimator, wherein the source unit is configured as a pre-assembled unit.

13. The gas analyzer of claim 12 ,
further comprising a filter configured to selectively transmit electromagnetic radiation emitted by the radiation source, wherein the filter comprises or is configured as a source unit filter separated from the collimator and supported by the holder.

14. The gas analyzer of claim 12 ,
wherein the holder comprises a substantially annular base portion and the plate-like carrier supporting the radiation source.

15. The gas analyzer of claim 14 ,
wherein the carrier is made of a material having a thermal conductivity of less than 5 W/(m·K).

16. The gas analyzer of claim 1 ,
wherein the radiation source comprises at least one of a group comprising: a photodiode and a laser.

17. The gas analyzer of claim 1 ,
wherein the gas chamber is delimited by a reflector configured to reflect electromagnetic radiation emitted by the radiation source.

18. The gas analyzer of claim 17 ,
wherein the reflector has a reflectance in the infrared and/or in the visible and/or in the ultraviolet frequency range of at least 20%, or of at least 50%, or of at least 80%.

19. The gas analyzer of claim 1 ,
wherein the gas chamber is in permanent gas flow communication with the exterior of the gas analyzer.

20. The gas analyzer of claim 1 ,
wherein the radiation source is configured to selectively excite gas molecules of a specific type that is to be detected in the gas received in the gas chamber in a time-varying fashion, thereby generating acoustic waves as the physical quantity indicative of the degree of interaction between the electromagnetic radiation emitted by the radiation source and gas molecules of the type that is to be detected in the gas received in the gas chamber, wherein the sensor comprises or is configured as an acoustic-wave sensor adapted to detect acoustic waves generated by the electromagnetic radiation.

21. The gas analyzer of claim 20 ,
wherein the sensor is positioned inside of the gas chamber.

22. The gas analyzer of claim 20 ,
wherein the sensor is positioned in a reference-gas chamber gas-tightly separated from the gas chamber and filled with a reference gas containing a well-defined amount of gas molecules of the type that is to be detected in the gas chamber.

23. The gas analyzer of claim 1 ,
wherein the sensor comprises or is configured as an optical sensor adapted to detect electromagnetic radiation emitted by the radiation source.

Assignees

• Infineon Technologies Ag

Inventors

• Glacer Christoph
• Dehe Alfons
• Tumpold David
• Onaran Gueclue

Classifications

• G01N21/6404 Primary

  Atomic fluorescence · CPC title

• G01N21/84

  Systems specially adapted for particular applications · CPC title

• G01N2021/1704

  in gases · CPC title

• G01N21/3504

  for analysing gases, e.g. multi-gas analysis · CPC title

• G01N2201/0633

  Directed, collimated illumination · CPC title