Fiber Optics

[Music] so good morning everyone will continue from where we left off in the last lecture we said they were learning outcome for this week is actually identifying the fundamental principles of photon optics and quantify photon properties but before we understand photon properties we need to understand electromagnetic properties of light so that's what we started doing yesterday

we said okay light actually travels as electromagnetic waves so it has to satisfy Maxwell's equations and then we saw how Maxwell's equations would be satisfied for a particular structure we took this example of an optical fiber right so we said if you consider an optical fiber you can say that the light is essentially you know from a ray

picture you can say that light is confined within waveguide through total internal reflection but then we saw that you know you really have to consider them as waves and so you need it basically accumulates face as it's propagating and to satisfy Maxwell's equations you need to satisfy the boundary conditions and as far as the

boundary conditions are concerned we were saying that we will you will have to have a consistent pattern of interference that is traveling all along the waveguide so yesterday I wanted to actually show you this this is something that I experienced as a student and it stuck to my mind but but let's say this is one

plane wave you know we are trying to explain how this this interference happens and how all these different modes develop so let's say this is one plane wave at traveling from this direction from from here to here and now we have a reflection from another plane wave right and the reflection is such that you know