Mr. Keegan McWilliams-Ward Profile

Keegan McWilliams-Ward

Engineer at HORIBA

SPIE Involvement:

Author

Publications (1)

This will count as one of your downloads.

You will have access to both the presentation and article (if available).

DOWNLOAD NOW

This content is available for download via your institution's subscription. To access this item, please sign in to your personal account.

Email or Username Forgot your username?

Password Forgot your password?

Show

Keep me signed in

No SPIE account? Create an account

Proceedings Article | 5 March 2021 Presentation + Paper

Compact and robust mid-infrared laser-based gas sensor for portable and real-time measurements

Kyoji Shibuya, Shota Hamauchi, Keegan McWilliams-Ward, Junichi Aoyama, Shigeru Nakatani

Proceedings Volume 11685, 116850G (2021) https://doi.org/10.1117/12.2578836

KEYWORDS: Gas sensors, Mid-IR, Gas lasers, Prototyping, Feature extraction, Detection and tracking algorithms, Temperature metrology, Signal processing, Sensors, Quantum cascade lasers

Read Abstract +

We propose a gas sensor using quantum cascade lasers which achieves high sensitivity and gas selectivity using a compact configuration and simple signal processing. This sensor features a small-volume Herriott cell and a simple concentration quantification algorithm. Our invented Herriott cell offers 5 m optical path length with only 40 mL internal volume. To preform concentration determination, feature quantities are extracted from an absorption signal by correlating the measured absorption signal with predetermined reference signals. The extracted feature quantities are used for the determination of target and interfering gas concentrations with simple simultaneous linear equations. The method is also capable of correcting for various disturbances, such as spectral shift due to laser wavelength drift and spectral broadening due to partial pressure changes of coexisting gases, by extracting additional, appropriate, feature quantities. This concentration quantification algorithm dramatically reduces calculation time compared to conventional spectral curve fitting methods because hundreds of spectral data points are replaced with a small number of feature quantities used during calculation. This approach allows the construction of a compact, fast-responding and robust gas sensor. We demonstrate a multicomponent and real-time measurement with a prototype of the proposed gas sensor. The prototype showed sub-ppm detection limits for NO, NO₂ and N₂O with 0.1 s integration time, and the interferences from high concentrations of H₂O and CO₂ could be removed completely. Furthermore, it was also shown that the prototype demonstrates excellent robustness against ambient temperature changes and spectral broadening effects caused by coexisting gases.

My Library

You currently do not have any folders to save your paper to! Create a new folder below.

Folder Name

Folder Description

View contact details

UPDATE YOUR PROFILE

Is this your profile? Update it now.

Sign into your SPIE.org account

Don’t have a profile and want one?

Create an account on SPIE.org

Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks. You are receiving this notice because your organization may not have SPIE eBooks access.*

*Shibboleth/Open Athens users─please sign in to access your institution's subscriptions.

To obtain this item, you may purchase the complete book in print or electronic format on SPIE.org.

ORGANIZATIONAL
Sign in with credentials provided by your organization.

Organizational Username

Organizational Password

Show/Hide Password

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available

Members:

Non-members: ADD TO CART

Keywords/Phrases

Search In:

Publication Years