Currently, in addition to high accuracy requirements instrumentation not less severe demands put forward, and their miniaturization and expansion functionality. All this involves the use of instrumentation in industrial complexes and systems of various types. The most accurate is now a device that measures the velocity of the liquid and gas flow, a laser doppler anemometer (hereinafter LDA). Together with the possibility of the include into its structure fiber-optic communication line as a system of formation of the probe radiation, LDA becomes a very effective means of measuring flow rates at easily attainable variations of linear dimensions of the system. For practical implementation of circuits LDA needs a stable power and frequency of the radiation source. In order to ensure minimizing the size of the source and achieve the desired values of the parameters of the radiation it is possible to use semiconductor laser diodes (LD), optimized for the spectral and spatial characteristics of radiation.