# Electromagnetic Waves & Optics: Lecture Notes

Notes from some random guy named Jacob that texts Lowa  
download to the original pdf  
https://cdn.discordapp.com/attachments/825759486936481856/1101510286374088795/EWO\_LNotes\_merged.pdf

# (pg 1) Preface.

<span class="markedContent" id="bkmrk-the-objective-of-the-1">  
<span dir="ltr" style="font-family:sans-serif;">The objective of the course is to provide an account of the study of optics taking up the</span>  
<span dir="ltr" style="font-family:sans-serif;">subject from where the study of electric and magnetic fields finished with the elucidation of</span>  
<span dir="ltr" style="font-family:sans-serif;">the Maxwell equations and developing these into a wave description of light. Some basics of</span>  
<span dir="ltr" style="font-family:sans-serif;">the properties of electromagnetic waves will be studied allowing an exploration of physical</span>  
<span dir="ltr" style="font-family:sans-serif;">optics.</span></span><span class="markedContent" id="bkmrk-"></span>

<span class="markedContent" id="bkmrk-as-with-any-subject%2C-1">  
<span dir="ltr" style="font-family:sans-serif;">As with any subject, it is necessary to begin by developing a language with which to discuss</span>  
<span dir="ltr" style="font-family:sans-serif;">the subject matter. In this case it is electromagnetic waves that are the subject of interest</span>  
<span dir="ltr" style="font-family:sans-serif;">and electromagnetic waves have several properties of interest in common with other waves;</span>  
<span dir="ltr" style="font-family:sans-serif;">sound, water, quantum mechanical etc. For the purposes of this study these include at the</span>  
<span dir="ltr" style="font-family:sans-serif;">top of the list the wave</span><span dir="ltr" style="font-family:sans-serif;"> </span><span dir="ltr" style="font-family:sans-serif;">amplitude</span><span dir="ltr" style="font-family:sans-serif;"> </span><span dir="ltr" style="font-family:sans-serif;">and</span><span dir="ltr" style="font-family:sans-serif;"> </span><span dir="ltr" style="font-family:sans-serif;">phase</span><span dir="ltr" style="font-family:sans-serif;">.</span></span><span class="markedContent" id="bkmrk--1"></span>

<span class="markedContent" id="bkmrk-the-module-outline-e-1">  
<span dir="ltr" style="font-family:sans-serif;">The</span><span dir="ltr" style="font-family:sans-serif;"> </span><span dir="ltr" style="font-family:sans-serif;">module</span><span dir="ltr" style="font-family:sans-serif;"> </span><span dir="ltr" style="font-family:sans-serif;">outline</span><span dir="ltr" style="font-family:sans-serif;"> </span><span dir="ltr" style="font-family:sans-serif;">eschews</span><span dir="ltr" style="font-family:sans-serif;"> </span><span dir="ltr" style="font-family:sans-serif;">traditional</span><span dir="ltr" style="font-family:sans-serif;"> </span><span dir="ltr" style="font-family:sans-serif;">development</span><span dir="ltr" style="font-family:sans-serif;"> </span><span dir="ltr" style="font-family:sans-serif;">of</span><span dir="ltr" style="font-family:sans-serif;"> </span><span dir="ltr" style="font-family:sans-serif;">the</span><span dir="ltr" style="font-family:sans-serif;"> </span><span dir="ltr" style="font-family:sans-serif;">subject</span><span dir="ltr" style="font-family:sans-serif;"> </span><span dir="ltr" style="font-family:sans-serif;">by beginning</span><span dir="ltr" style="font-family:sans-serif;"> </span><span dir="ltr" style="font-family:sans-serif;">with</span>  
<span dir="ltr" style="font-family:sans-serif;">physical optics before going on to geometric optics in keeping with its emphasis on the</span>  
<span dir="ltr" style="font-family:sans-serif;">electromagnetic wave nature of light. The development of the module will proceed as follows;</span></span><span class="markedContent" id="bkmrk--2"></span>

- <span class="markedContent" id="bkmrk-i%29-the-module-begins-1"><span dir="ltr" style="font-family:sans-serif;">i)</span><span dir="ltr" style="font-family:sans-serif;"> </span><span dir="ltr" style="font-family:sans-serif;">The module begins by exploring the meaning of the amplitude of the EM wave, in</span>  
    <span dir="ltr" style="font-family:sans-serif;">terms of the electric field (and in terms of the accompanying magnetic field) and its</span>  
    <span dir="ltr" style="font-family:sans-serif;">relationship to the intensity (power per unit area) carried by that wave. This will enable</span>  
    <span dir="ltr" style="font-family:sans-serif;">the development of an understanding of how transmission and reflection at a dielectric</span>  
    <span dir="ltr" style="font-family:sans-serif;">interface may be described and evaluated.</span></span><span class="markedContent" id="bkmrk--3"></span>
- <span class="markedContent" id="bkmrk-ii%29-the-module-will-"><span dir="ltr" style="font-family:sans-serif;">ii)</span><span dir="ltr" style="font-family:sans-serif;"> </span><span dir="ltr" style="font-family:sans-serif;">The module will then focus on the phase of the wave and how this is to be used in</span>  
    <span dir="ltr" style="font-family:sans-serif;">circumstances (the most general ones) where the overall optical effect is produced by</span>  
    <span dir="ltr" style="font-family:sans-serif;">a superposition of many waves; specifically in interference and diffraction effects.</span></span><span class="markedContent" id="bkmrk--4"></span>
- <span class="markedContent" id="bkmrk-iii%29-geometric-optic"><span dir="ltr" style="font-family:sans-serif;">iii)</span><span dir="ltr" style="font-family:sans-serif;"> </span><span dir="ltr" style="font-family:sans-serif;">Geometric optics will then, ignoring the wave properties</span><span dir="ltr" style="font-family:sans-serif;"> </span><span dir="ltr" style="font-family:sans-serif;">of the light, provide an</span>  
    <span dir="ltr" style="font-family:sans-serif;">understanding of simple optical components and the use of such components in some</span>  
    <span dir="ltr" style="font-family:sans-serif;">common optical instruments.</span></span><span class="markedContent" id="bkmrk--5">  
    </span>
- <span class="markedContent" id="bkmrk-iv%29-the-course-will-"><span dir="ltr" style="font-family:sans-serif;">iv)</span><span dir="ltr" style="font-family:sans-serif;"> </span><span dir="ltr" style="font-family:sans-serif;">The</span><span dir="ltr" style="font-family:sans-serif;"> </span><span dir="ltr" style="font-family:sans-serif;">course will end</span><span dir="ltr" style="font-family:sans-serif;"> </span><span dir="ltr" style="font-family:sans-serif;">by exploring some of the quantum aspects of light and</span><span dir="ltr" style="font-family:sans-serif;"> </span><span dir="ltr" style="font-family:sans-serif;">in</span>  
    <span dir="ltr" style="font-family:sans-serif;">particular a simple description of the interaction of light with matter by describing that</span>  
    <span dir="ltr" style="font-family:sans-serif;">interaction in terms of a basic two (quantum) level system.</span></span>

# (pg 2) Maxwells Equations & the Wave Equation (draft)

<span class="markedContent" id="bkmrk-maxwell%E2%80%99s-equations--1"><span dir="ltr" style="font-family:sans-serif;">Maxwell’s equations in free space.</span></span><span class="markedContent" id="bkmrk-the-starting-point-o">  
<span dir="ltr" style="font-family:sans-serif;">The starting point of this course is where the first year electromagnetism course ended,</span>  
<span dir="ltr" style="font-family:sans-serif;">namely with the four Maxwell’s equations and the electromagnetic wave equation.</span><span dir="ltr" style="font-family:sans-serif;"> </span><span dir="ltr" style="font-family:sans-serif;">A review</span>  
<span dir="ltr" style="font-family:sans-serif;">of these equations is therefore a good place to start.</span></span><span class="markedContent" id="bkmrk-beginning-with-the-s">  
<span dir="ltr" style="font-family:sans-serif;">Beginning with the simplest situation of Maxwell’s equations in</span><span dir="ltr" style="font-family:sans-serif;"> </span><span dir="ltr" style="font-family:sans-serif;">a vacuum (no charges or</span>  
<span dir="ltr" style="font-family:sans-serif;">currents ). There are a set of four equations, established by Maxwell, that relate the magnetic</span>  
<span dir="ltr" style="font-family:sans-serif;">fields and the electric fields. These equations may be written in differential form as:</span></span>

[![image.png](https://library.naruzkurai.tk/uploads/images/gallery/2023-04/scaled-1680-/LFOCh1p3rucOE0Le-image.png)](https://library.naruzkurai.tk/uploads/images/gallery/2023-04/LFOCh1p3rucOE0Le-image.png)

<span class="markedContent" id="bkmrk--2"></span>