Other Elements of Optical Gas Sensors

Common to refractive elements in both wavelength ranges is the problem of chromatic aberration. Therefore, mirror optics is usually applied in particular in the mid-lR. Reflecting coatings applied to a surface for operation in the visible and near-infrared ranges can be silver, aluminum, chromium. 

Planar couplers, polarizers, and phase modulators required for integrated optical gas sensors can easily be realized as a single chip on Uthium niobate. A planar LiNbOj phase modulator consists of a 

14 Materials for Optical, Fiber Optic, and Integrated Optical Sensors 

Allen MG (1998) Diode laser absorption sensors for gas-dynamic and combustion flows. Meas Sci Technol 9 545-562 Anderson MS, Andringa JM, Carlson RW, Conrad P, Hartford W, Shafer M, Soto A, Tsapin AI, Dybwad JP, Wadsworth W, Hand K (2005) Fourier transform infrared spectroscopy for Mars science. Rev Sci Instrum 76 034101 Ashizawa H, Yamaguchi S, Endo M, Ohara S, Takahashi M, Nanri K, Fujioka T (2003) Development of a nitrogen dioxide gas sensor based on mid-infrared absorption spectroscopy. Rev Laser Eng 31 151-155 Baldini F, Chester AN, Homola J, Martellucci S (eds) (2006) Optical chemical sensors. Springer, Dordrecht Bansal L (2004) Development of a fiber optic chemical sensor for detection of toxic vapors. Ph.D. thesis, Drexel University, Philadelphia, PA 

Bass M, Van Stryland EW (eds) (2002) Fiber optic handbook fiber, devices, and systems for optical communications. McGraw-Hill, New York 

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