Sensitivity enhancement in off-axis integrated cavity output spectroscopy.
نویسندگان
چکیده
We report on a detailed model of an improved three mirror off-axis integrated cavity output spectroscopy (OA-ICOS) setup, which re-injects the light reflected by the optical cavity. The model simulates the impact of design parameters on instrument sensitivity and can be used for any off-axis configuration. We demonstrate the application of this model for the real-time detection of ethylene with a pulsed quantum cascade laser (QCL). The three mirror OA-ICOS scheme provides a 10 times increase in signal-to-noise ratio as compared to standard OA-ICOS, resulting in a noise equivalent absorption sensitivity of 1.5 x 10(-8) cm(-1) Hz(-1/2).
منابع مشابه
Off-axis integrated cavity output spectroscopy with a mid-infrared interband cascade laser for real-time breath ethane measurements.
Cavity-enhanced tunable diode laser absorption spectroscopy is an attractive method for measuring small concentrations of gaseous species. Ethane is a breath biomarker of lipid peroxidation initiated by reactive oxygen species. A noninvasive means of quickly quantifying oxidative stress status has the potential for broad clinical application. We present a simple, compact system using off-axis i...
متن کاملMid-infrared quantum cascade laser based off-axis integrated cavity output spectroscopy for biogenic nitric oxide detection.
Tunable-laser absorption spectroscopy in the mid-IR spectral region is a sensitive analytical technique for trace-gas quantification. The detection of nitric oxide (NO) in exhaled breath is of particular interest in the diagnosis of lower-airway inflammation associated with a number of lung diseases and illnesses. A gas analyzer based on a continuous-wave mid-IR quantum cascade laser operating ...
متن کاملDesign considerations in high-sensitivity off- axis integrated cavity output spectroscopy
Off-axis integrated cavity output spectroscopy (OA-ICOS) has generated much interest because it potentially allows highly sensitive field measurements with robust optical alignment. We discuss here design choices involved in design of an OA-ICOS instrument and how these choices impact instrument sensitivity, using as our example the design of the Harvard ICOS isotope instrument, which demonstra...
متن کاملOptimum signal-to-noise ratio in off-axis integrated cavity output spectroscopy.
The signal-to-noise ratio (SNR) in off-axis integrated cavity output spectroscopy (OA-ICOS) is investigated and compared to direct absorption spectroscopy using multipass absorption cells [tunable diode laser absorption spectroscopy (TDLAS)]. Applying measured noise characteristics of a near-IR tunable diode laser and detector, it is shown that the optimum SNR is not generally reached at the hi...
متن کاملReal-time, subsecond, multicomponent breath analysis by Optical Parametric Oscillator based Off-Axis Integrated Cavity Output Spectroscopy.
Breath analysis is an attractive field of research, due to its high potential for non-invasive medical diagnostics. Among others, laser-based absorption spectroscopy is an excellent method for the detection of gases in exhaled breath, because it can combine a high sensitivity with a good selectivity, and a high temporal resolution. Here, we use a fast-scanning continuous wave, singly-resonant O...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
- Optics express
دوره 22 23 شماره
صفحات -
تاریخ انتشار 2014