Scientific paper ID 857 : 2013/3

In the presented work is discussed in terms of stabilized short-term fluctuations of the output radiation power He-Ne laser with a power of 1 mW and a wavelength of 632,8 nm. Such lasers are widely used in the field of laser sensors of physical quantities (noncontact measurements of vibrations and the like.), wherein the low level of optical noise is one of the main parameters determining the sensitivity of the system. At work it was determined that the main source of noise and transient instabilities in the power of the laser pulses are the noises arising from the supply voltage due to pulses of the laser supply. Switching power supply of the type of laser (LHN 101P) operating at a fundamental frequency about 20 kHz. For the stabilization of the output power and reduce the level of optical noise is developed two-tier high-voltage low-pass filter through which the supply current of the laser passes. Using this filter, allows the level of optical noise and short term fluctuations can be reduced to a very low level below the level of sensitivity of the opto-electronic registering apparatus, which is 1 mV. In the presented work is further conducted numerical modeling and analysis of such filters for the purpose of stabilized He-Ne lasers.