A method is proposed for transferring a unit of laser radiation power to power measuring instruments of kilowatt levels with the possibility of constant monitoring of the transmission process. A measuring optical laser power divider has been developed, which is structurally made in the form of a wedge and allows one to determine the radiation power of the beam delivered to the calibrated measuring instrument using the relatively small radiation power reflected from the enlightened surface of the front edge of the wedge. The proposed method is based on the application of the developed divider in the reference installation and provides for the implementation of three modes of operation of the installation: the mode of determining the equivalence coefficient; the mode of determining the division ratio of the optical divider; transmission mode of a power unit to measuring instruments and determination of a control parameter of an optical divider. The control of the transmission process is carried out by measuring the radiation power reflected from the rear edge of the wedge, and determining the control parameter. The conditions are given under which it is advisable to use the proposed mode for determining the division coefficient of the optical divider. A feature of the method under consideration is the possibility of operational control of the division coefficient of the optical divider, which allows real-time assessment of the accuracy of the calibration process of measuring instruments. The formula of metrological traceability of the results of power measurements to GET 28-2016 is obtained. The main components of the error in determining the radiation power supplied to the input of a calibrated measuring instrument are considered. The results of experimental studies of the method suggest that at a wavelength of 10,6 μm, the total error of power measurement, expressed as the standard deviation, does not exceed 2,0 %. The method can be used in the corresponding secondary power unit standards that receive a unit from the State Special Standard for Average Power GET 28-2016.
Creation of the national measurement standard of the units of average power and energy of laser radiation of the Republic of Belarus
