Measurement of (12)CO(2):(13)CO(2) ratios for medical diagnostics with 1.6-µm distributed-feedback semiconductor diode lasers.
We have observed some of the absorption lines from the molecules (12)CO(2) and (13)CO(2)in the 1.6-µm spectral region with the use of specially fabricated single-mode InGaAsP distributed-feedback semiconductor diode lasers. Using a 23.6-m-long multipass absorption cell in combination with radio-frequency modulation and detection techniques, we measured the (12)CO(2):(13)CO(2) isotopic ratio of two specific lines at 6253.73 and 6253.90 cm(-1) with sufficient precision for diagnostic medical tests that analyze CO(2) on human breath.
Cooper
D E
DE
Martinelli
R U
RU
Carlisle
C B
CB
Riris
H
H
Bour
D B
DB
Menna
R J
RJ