Задача 40386.

A thin layer of a transparent substance with a refractive index n=1.3 is applied to a glass plate. The plate is illuminated by a parallel beam of monochromatic light with a wavelength of 640 nm, incident normally on the plate. What minimum thickness must the layer have in order for the reflected beam to have the lowest brightness?

Detailed solution with a brief record of the conditions, formulas and laws used in the solution, derivation of the calculation formula and answer.
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