摘要：An optimized design of laser range finding system using the self-mixing effect in a single-mode verticalcavity surface-emitting laser （VCSEL） is proposed. In order to improve the ranging accuracy and expand dynamic measurement range, we apply difference frequency analog phase-locked loop （PLL） instead of fast Fourier transform （FFT） to process signal, and choose the optimum triangular wave frequency .fm= 500 Hz and small modulation current △Ip p = 0.28 mA to modulate single-mode VCSEL. The experiment results show that, without controlling the laser＇s temperature, the ranging accuracy is better than 2 mm and the measurement dynamic range is as large as 50-500 mm when the sampling time is 0.1 s and the room temperature is 0--55℃.

摘要：A laser-induced chemical vapor deposition (LICVD) nanometer equipment is designed and fabricated. The design conception of key parts is expatiated. The energy threshold of SiH4 decomposing is studied. In the condition of same reactive gas flux, the laser energy threshold decreases with the increase of SiH4 concentration. In the condition of same SiH4 concentration, with the increase of reactive gas flux, the laser energy threshold which induces SiH4 decomposition increases linearly at the beginning, and when the flux is more than 100 ml/min, it turns to increase slowly. The factors which influence the laser threshold are analyzed.