[1] [1] I. Linnerud, P. Kaspersen, T. Jaeger. Gas monitoring in the process industry using diode laser spectroscopy. Appl. Phys. B, 1998, 67(3):297～305

[2] [2] H. Riris, C. B. Carlisle, L. W. Carr et al.. Design of an open path near-infrared diode laser sensor: application to oxygen, water, and carbon dioxide vapor detection. Appl. Opt., 1994, 33(30):7059～7066

[3] [3] K. C. Harvey, C. J. Myatt. External-cavity diode laser using a grazing-incidence diffraction grating. Opt. Lett., 1991, 16(12):910～912

[4] [4] D. B. Oh, D. C. Hovde. Wavelength-modulation detection of acetylene with a near-infrared external-cavity diode laser. Appl. Opt., 1995, 34(30):7002～7005

[5] [5] Q. V. Nguyen, R. W. Dibble. High-resolution oxygen absorption spectrum obtained with an external-cavity continuously tunable diode laser. Opt. Lett., 1994, 19(24):2134～2136

[6] [6] J. A. Silver. Frequency modulation spectroscopy for trace species detection: theory and comparison among experimental methods. Appl. Opt., 1992, 31(6):707～717

[7] [7] E. I. Moses, C. L. Tang. High-sensitivity laser wavelength-modulation spectroscopy. Opt. Lett., 1977, 1(4):115～117

[8] [8] A. N. Dharamsi, A. M. Bullock. Applications of wavelength-modulation spectroscopy in resolution of pressure and modulation broadened spectra. Appl. Phys. B, 1996, 63(3):283～292

[9] [9] A. N. Dharamsi, Y. Lu. Sensitive density-fluctuation measurements using wavelength-modulation spectroscopy with high-order-harmonic detection. Appl. Phys. B, 1996, 62(3):273～278

[10] [10] D. M. Bruce, D. T. Cassidy. Detection of oxygen using short external cavity GaAs semiconductor diode lasers. Appl. Opt., 1990, 29(9):1327～1332

[11] [11] D. T. Cassidy, D. M. Bruce, B. F. Ventrudo. Short-external-cavity module for enhanced single-mode tuning of InGaAsP and AlGaAs semiconductor diode lasers. Rev. Sci. Instrum., 1991, 62(10):2385～2388