The invention relates to a method for measuring thicknesses of materials
of multilayered structure. This method includes transmitting one or more
ultrasound signals including different frequencies into a multilayered
structure consisting of two or more materials with one or more ultrasound
transducers, measuring materials, acoustic properties for which are
different at the frequencies in use, measuring ultrasound signals
reflected from the front surface and back surface of the multilayered
structure with one or more ultrasound transducer and determining
thicknesses of the materials within multilayered structure from the
reflected ultrasound signals.