A CD is read by a semiconductor laser that emits a light with a wavelength of 798nm in air. The beam passes through a plastic substrate of refractive index 1.9. When half the beam illuminates a pit in the disc, part of the beam is reflected from the pit and the other part from the flat plateau between the pits, so that these two parts of the steel extinguish each other. What must the minimum pit depth be so that the part of the beam reflected from a pit extinguishes the part of the beam reflected from the flat plateau?

A CD is read by a semiconductor laser that emits a light with a wavelength of 798nm in air. The beam passes through a plastic substrate of refractive index 1.9. When half the beam illuminates a pit in the disc, part of the beam is reflected from the pit and the other part from the flat plateau between the pits, so that these two parts of the steel extinguish each other. What must the minimum pit depth be so that the part of the beam reflected from a pit extinguishes the part of the beam reflected from the flat plateau?

Principles of Physics: A Calculus-Based Text

5th Edition

ISBN:9781133104261

Author:Raymond A. Serway, John W. Jewett

Publisher:Raymond A. Serway, John W. Jewett

Chapter27: Wave Optics

Section: Chapter Questions

Problem 32P

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