Increasing the accuracy of the fast laser measurments transparent solid and liquid films thicknesses
- Ph.D., Dr.Sci. professor Saint-Petersburg Mining University
Abstract
Nondestructive optical methods for measuring of the «thick» films thickness of the order of 0,001-1,00 mm are analyzed. It is shown that using the laser beam radiation and modern optical and electronic schemes possible to decrease the time of single measurement to 1ms and less at the measuring frequency of 10-50 Hz. The possibility of measuring thickness and spreading coefficient and evaporation kinetics of liquid films is demonstrated. A new computer method of the data processing aimed to determine the film thickness from the angle dependence of the laser beam reflection coefficient by the film is offered. The offered procedure and the experimental technique realizing it permits to decrease the thickness determination uncertainty to the order of ten.