3. Colored films and "black" films

3.1 Water drainage

Let us now examine water drainage in a soap film. The first studies on soap films date back more than three centuries; the pioneers were Robert Hooke, an English physicist, father of the multi-lens microscope and biologist (1635-1703), Isaac Newton, an English philosopher, mathematician, physicist and astronomer (1643-1727), and Gibbs (1839-1903). I. Newton described his observations in detail, but also very poetically, in his treatise on optics.

Soap films appear colored (Figure ) as they thin under the effect of gravity, once their thickness falls below one-tenth of a micrometer [2] .

When a vertical film is formed...