If youre behind a web filter, please make sure that the domains. This situation is typical for optical phenomena, components, and systems. Here v 1 and v 2 are the speed of light in media 1 and 2 with refractive index pp 12 and respectively. Basic principles of geometric optics, interference and diffraction, including fourier methods. We will instead spend most of this book making use of a simpler model of light, the ray model, which does a fine job in most practical situations. Knowing this, however, is not the same as knowing everything about eyes and telescopes. This demonstration visualizes the field, energy distribution, and propagation of light in step index fibers. While we cannot see these extremely rapid oscillations, their wave behavior is similar to that of water waves. Resonant nonlinear optics of backward waves in negativeindex metamaterials. Wave optics theory and 3d deconvolution for the light. An electromagnetic wave traveling along an x axis has an electric. It employs an array of microlenses to trade off spatial resolution against angular resolution, thereby allowing a 4d light field to be captured using a single photographic exposure without the need for scanning.
As we remember plane waves have the following structure. Its technological use by marconi and others led in due course to the revolution in communication that we are witnessing today. Light field microscopy is a new technique for highspeed volumetric imaging of weakly scattering or fluorescent specimens. If you are reading the documentation as a pdf file on your computer, the. Light or other electromagnetic waves can propagate through optical fibers. For simplicity, we will focus on the most commonly used solution the harmonic plane wave. Suppose that the wave is linearly polarized in the direction. Note that the observed laws of geometric optics follow from the assumption that light is a wave. Wave equation maxwells equations contain the wave equation for electromagnetic waves. This course will focus on waves and the interaction of light and matter as described with optics and quantum mechanics physics and astrophysics are really awesome. As a result, constructive inter ference occurs at this location, and a bright fringe is obser ved. In 1801, british physicist thomas young showed experimentally by interference experiment that light also has wave nature and thus wave optics came into existence. The recorded light field can then be used to computationally.
The electromagnetic wave equation is a second order partial differential equation. Let us call the direction in which the wave travels the x axis. Hertz, in 1885, experimentally demonstrated the existence of electromagnetic waves. According to huygens principle light emits in the form of waves and source of lights is a center of disturbance from which waves spread in all direction. The speed v of a wave is given by v t o where is the wavelength of the wave and t 1 is the period of oscillation. Maxwells equations contain the wave equation for electromagnetic waves.
Solutions to the wave equations can take different forms. In addition to the wave fronts from the source a graph depicting the time of emission and time of detection of. Furthermore, and are also perpendicular to each other and oscillate together, in phase with each other, as the wave travels along at speed c. Superposition of waves, group velocity, poynting vector 4. Hernandez department of physics and astronomy, university of north carolina, chapel hill the basic laws of geometrical optics can be deduced from energymomentum conservation for electromagnetic waves, without other wave concepts. Choose your answers to the questions and click next to see the next set of questions. Daviddarom, wikimedia commons learning objectives 24. Wave optics class 12 physics india science khan academy. The energy of the wave travels in a direction perpendicular to the wavefront. Electric field and magnetic induction for an elliptically polarized wave. Which travel in all directions with the velocity of light in the medium. Electromagnetic wave theory university of washington. When light crosses a boundary between two different optical media, its fre. Electromagnetics, waves, and optics college physics.
Electromagnetic waves an electromagnetic wave consists of oscillating electric and magnetic. E and b are perpendicular to each other in a manner such that e. Youve got half of the answer right when mentioning faradays law of induction, which tells us how electric fields can be generated from timevarying magnetic fields. Electromagnetic wave equation describes the propagation of electromagnetic waves in a vacuum or through a medium. You can skip questions if you would like and come back to them. Geometrical optics via electromagnetic wave quantization. Because light is a wave, the superposition principle is valid to determine the constructive and destructive interferences for light waves. While a mechanical wave such as a sound wave exists in a medium, waves of electromagnetic radiation including light can travel through vacuum, that is, without any medium. This book is downloadable in pdf, epub, kindle and txt format. Consider a single slit diffraction pattern for a slit of width d. Because both waves travel the same distance, they arrive at p in phase.
Important dates biweekly exams will be on fridays, except for the last one. Geometrical optics, studied in the first year, ignored the wave nature of light and so, in this. But we had learnt all waves have common characteristic properties such as. However, 2in some of the answers, this value was rounded to 10 ms usually, for problems where the.
This wave nature of light is the basis of physical optics and describes the. Electromagnetic waves predicted and observed restate maxwells. Thus, we find it useful to picture waves and wave motion in terms of simple water waves, such as those. They should note that the pencil appears to bend at the airwater interface, and explain this apparent bending. Find the value of d if the angle between the first minimum and the central maximum is 4103 radians and the wavelength of the light is 633 nm. Goals for chapter 32 to do an overview of maxwells equations and electromagnetic waves to study sinusoidal electromagnetic waves to consider the passage of electromagnetic waves through matter to determine the energy and momentum of electromagnetic waves to observe wave addition, the formation of a standing. This section serves as motivation for the fact that light is an electromagnetic wave. Describe how electromagnetic waves are similar to and. When two waves of exactly same frequency coming from two coherent sources travels in a medium, in the same direction simultaneously then due to their superposition, at some points intensity of light is maximum while at some other points intensity is minimum. Workshop tutorials for physics waves and optics activities 185 bent pencil apparatus transparent container of water, for example a glass beaker, pencil action the students observe the pencil through side of the container.
In a plane wave, all points on the wavefront are in phase and oscillate together figure 22. The electromagnetic spectrum is formed by the various possible frequencies. Taylor and amnon yariv, fellow, ieee invited paper aavmcrphenomena associated with the propagation and manipula tion of light in thinfh dielectric waveguides are presently the object of qdenble reseuch effort, directed towrat possiile appliations in communications and information pmcesbg. This course will be challenging and will include lots of interesting material.
These phenomena cannot be adequately explained with the ray optics used in chapters 35 and 36. Consider a plane electromagnetic wave, linearly polarized in the direction, that propagates in the direction through a transparent dielectric medium, such as glass or water. Such idealized plane waves can be fairly well represented by a laser beam, as we show in chapter 25. Periodic waves are characterized by crests highs and troughs lows, as shown in figure 23. Geometrical optics via electromagnetic wave quantization john p. This book contains fundamentals of oscillations and waves and properties of electromagnetic waves. Substitute amperes law for a charge and currentfree region. Wave optics theory and 3d deconvolution for the light field. Here is the core radius and is the angular frequency. The total energy density for an electromagnetic wave is the sum of the two energy densities. An electromagnetic wave has an electric field e and a magnetic field b.
The simplest case we may consider is that of electrodynamics of isotropic media 2. Basic physical optics 121 figure 41 water waves and wave fronts the bobbing cork generates a series of surface disturbances that travel outward from the cork. Problems near the surface of the earth involve gravitational acceleration equal to 9. Dielectric waveguides, their understanding in terms of geometric optics, paraxial approximation, slowly varying amplitude approximation, analogy with the schrodinger equation 5. Describe the six properties of electromagnetic waves and give everyday examples. If youre seeing this message, it means were having trouble loading external resources on our website. If you are reading the documentation as a pdf file on your computer, the blue. Electromagnetic waves the electromagnetic wave consists of oscillating electric e and magnetic b fields. Physics of waves and wave motion wave optics treats light as a series of propagating electric and magnetic field oscillations. Electromagnetic waves and optics linkedin slideshare. This is the threedimensional wave equation in vector form. However, with the wave optics module you can do timeharmonic simulations of domains that are much larger than the wavelength. Resonant nonlinear optics of backward waves in negative. Electromagnetic waves consider a plane electromagnetic wave propagating through a vacuum in the direction.
Physical or wave optics is the study of such situations and includes all wave. We can write each of the magnitudes of the fields in the form of traveling waves as in section 3 of chapter 10 19. If we have a point source emitting waves uniformly in all directions, then the locus of points which have the same amplitude and vibrate in the same phase are spheres and we have what is known as a spherical wave as shown in fig. Calculate water wave displacement on a sinusoidlike waveform as a function of time and position. Waves and optics regular waves and optics worksheets and solutions wr1b.
Both the rf and the wave optics module can handle highfrequency electromagnetic wave simulations. An asterisk is used to designate a problem that does not have an answer at the back of the book. Classical electromagnetism and optics c y x z e h figure 2. Dec 07, 2011 goals for chapter 32 to do an overview of maxwells equations and electromagnetic waves to study sinusoidal electromagnetic waves to consider the passage of electromagnetic waves through matter to determine the energy and momentum of electromagnetic waves to observe wave addition, the formation of a standing. Figure 41b shows the same disturbances traveling away from point a the cork as a series of successive wave fronts labeled crests and troughs. With 272 selected problems and answers, this study aid is a powerful supplement to the study of wave optics. Ray optics is based on rectilinear propagation of light, and deals with mirrors, lenses, reflection, refraction, etc. Wave motion occurs when a disturbance at point a, at time to, is related to what happens at point b, at time t t0. Monday, 25th may is a holiday memorial day final exam will be between 6 and 12th june commencement will be on the following weekend 14 june. A clear understanding of em wave propagation depends on a grasp of what waves are in general. As is wellknown fitzpatrick 2008, the electric component of the wave causes the neutral molecules making up the medium to polarize. The periodic solution of the wave equation for the modes and has to be axisymmetrical. A step index fiber is composed of a core and cladding that have different refractive indices and, respectively.
Interference in light waves is not easy to observe because the wavelengths are so short. Electromagnetic waves or em radiation has two constituents. Recall that a wave front is a locus of points along which all phases and displacements are. In fact, the full description of light as a wave can be rather cumbersome. The sound wave of our speech has a wavelength of about 5. Covering the basics of wave propagation, reflection, refraction, anisotropic media, interference, diffraction, and coherence, this questionandanswer collection provides the opportunity to solve problems chosen by a mentor with decades. One uses a planar waveguide setup, where enhanced transmission. The wave phenomenon itself is an oscillation where the variations of magnetic field create and induced electric field, and conversly the variation of the electric field induce a magnetic field. Geometric optics vs electromagnetic waves physics forums.
The wave optics module users guide comsol documentation. The fields e and b and are perpendicular to the direction of propagation v em. Explain how the energy and amplitude of an electromagnetic wave are related. Find the value of d if the angle between the first minimum and the central maximum is 4103 radians and the wavelength of the light is 633 nm solution. The planes of the fields are at right angles to each other and to the direction in which the wave is travelling. Lecture 21 reminderintroduction to wave optics program. Electromagnetic waves, the electromagnetic spectrum and photons opens a modal electromagnetic waves and the electromagnetic spectrum opens a modal red shift opens a modal. A diffraction grating is an optical component that serves to periodically. The doppler effect model displays the detection of sound waves from a moving source and the change in frequency of the detected wave via the doppler effect. Farfield support in the electromagnetic waves, frequency domain. Here in chapter 37 and in the next chapter, we are concerned with wave optics or physical optics, the study of inter ference, diffraction, and polarization of light. Transverse electromagnetic wave tem 6 with the refractive index n v r and the free space impedance r zf0. Electromagnetics, waves, and optics for most people, the nearest distance that objects can be located away from the eye and still seen clearly is.
The frequency remains the same as light travels from one medium to another. This is a property of a wave in general, and can be seen in sound waves too. At an interface between two media, the file quantities must satisfy. Then you come to the chapter on wave optics, and you are told that light travels as a wave, that it can bend around objects, it can diffract and interfere, etc. Abstract the extraordinary properties of resonant four wave mixing of backward and ordinary electromagnetic waves in doped negativeindex materials are investigated. Chapter 2 classical electromagnetism and optics the classical electromagnetic phenomena are completely described by maxwells equations. Electromagnetic optics optics is a branch of electromagnetism electromagnetic optics include both wave optics scalar approximation ray optics limit when. The various possible frequencies of electromagnetic waves form a spectrum, a small part of which is visible light. Incidentally, electromagnetic waves are the only commonly occurring waves that do not require a medium through which to propagate. Maxwells work thus unified the domain of electricity, magnetism and light. Electromagnetism and optics a complete set of lecture notes for a lowerdivision undergraduate electromagnetism and optics course.
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