The title Optics 2, which is aimed at high school as well as university students, begins by introducing the index of a transparent medium calculated from the speed of light in the medium where it propagates. The subject of the phase of an electromagnetic wave, introduced in Optics 1, is covered once again. This follow-up allows us to prove the laws of reflection and refraction, in particular the Snell-Descartes Law.
After studying the images formed by a plane mirror, we move on to the study of refraction, in particular the study of plane diopter, spherical diopter and thick lenses. Throughout this chapter, we use the coordinates of Newton's formula XX'=ff', which is easy to memorize and use. This approach, which can be considered university-level, enables is to show that the lens formulas result from the laws of refraction.
The study and graph of the Snell-Descartes Law enables the introduction of the critical angle of refaction and its use in fiber optics.
Two important applications are covered in the course and in the form of exercises :
. The prism and its uses, in particular the measure of index n,
. Reflections-refractions by a spherical drop of water and the calculations which give the positions of the rays of a single or double rainbow.
The applications of reflection are studied in three chapters devoted to concave, convex and parabolic mirrors, with the introdution of Fermat's Pricipal.
As an example of the principal application of mirrors, the Hubble Space Telescope is studied in the form of a problem with the diagram drawn to scale and the calculations based on Newton's relations. Extraordinary images taken by the telescope are presented with commentary.Chapter 14 covers the study of lenses, the definitions of linear and angular magnification. The association of two lenses is applied to vision correction. The microscope is studied in the form of courses and exercises. An exercise is devoted to astronomical telescopes.
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It’s easy to think that all you need to carry with you these days is a smartphone and you’re ready for anything. But some extended periods away from my desk have discovered four things that are ‘must-haves’ for the traveller.