A need exists to develop a smaller, lighter, more efficient and more reliable clinical as analyzer for respiratory and anesthetic gas monitoring. Existing laser Raman based nstrumentation uses a large, heavy and extremely inefficient (0.1 %) argon ion laser with an intracavity gas cell. The long term objective of this study is to implement a solid state alternative to the existing ion laser. Such a laser is smaller, lighter, much more efficient and has lifetimes greatly exceeding that of the present laser.
The specific aims are: (1) build a prototype utilizing the solid state laser which pumps a passive external cavity containing a multi-channel gas cell, selected specific dielectric interference filters for rejection of the elastic scattered laser light and transmission of gas specific Raman lines, and solid state photodetectors, (2) evaluate the prototype for accuracy, linearity, sensitivity, precision, stability and interference between various anesthetic and respiratory gases, and (3) validate the prototype feasibility by comparing the signal levels for pure gases to those caluculated on the basis of a system modelling equation.
