High accuracy nondestructive measuring of the thickness of transparent solid and liquid films

Polymer nanocomposite films can be made impenetrable to air, light, aromatic substances, steam. This stipulates their wide use for packaging, primarily food products. Such films thickness control is an important technological moment of their manufacturing, and it must be non-contact and non-destructive. Most of films made of nanocomposite polymers are transparent to visible and infrared light. In this article a new 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 permit to decrease the thickness determination uncertainty to 150 nm while measuring the film thickness in the range from 0,01 mm to 1,0 mm. (paper)