17 Jun 2002
A gas sensor system based on quantum cascade laser technology promises sensitivities of below 10 ppb.
The first ever integrated gas sensors based on quantum cascade laser (QCL) technology have been launched by US company Physical Sciences Incorporated (PSI).
Using QCL technology licensed from Federico Capasso's group at Bell Labs and PSI's proprietary ultra-sensitive detection methods, the systems have sensitivities below 10 ppb at atmospheric pressure.
The first two sensors are for NO and CO detection. Using a 5.2 µm, distributed-feedback room-temperature QCL operating with over 1 mW average power, the QCL-NO-1001 sensor provides continuous detection of NO with 10 ppb sensitivity in a 10 Hz bandwidth at atmospheric pressure and temperature.
The model QCL-CO-1001 sensor achieves the same specifications for CO detection using a 4.6 µm QCL.
In both sensors, the QCL is mounted in a custom-fabricated housing, complete with thermo-electric cooler, beam-shaping optics and pulsed current supply. The systems feature fully-integrated software control and sufficient electro-optic components to setup a complete absorption measurement.
Additional sensors for SO2, SO3, and formaldehyde are presently under development and will be available commercially before the end of 2002.
Nadya Anscombe is editor of Optics.org and Opto & Laser Europe magazine.