Longitudal waves are those in which the displacement of the mediumor eld is in the direction of the wave. However, it slows somewhat when traveling through a medium. In particular, optics is concerned with the generation and. 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. Light and geometrical optics test 1 kaplan 3 passage i questions 16 figure 1 shows a simplified model of the eye that is based on the assumption that all of the refraction of entering light occurs at the cornea.
Under geometric optics, we express the geodesic equations in hamiltonian form and solve perturbatively for the e ect of gravitational waves. Wave theory of light by huygens, fresnel, young, etc in geometric optics we learnt light is a stream of straightgoing particles newton proposed that first then we learnt light is a form of em wave. Because light is an electromagnetic wave, other forms of electromagnetic radiation such as xrays, microwaves, and radio waves. Apr 11, 2020 chapter notes wave optics, class 12, physics class 12 notes edurev is made by best teachers of class 12. Geometrical optics in describing the propagation of light as a wave we need to understand. Geometric optics is discussed as an approximation to wave theory when the wavelength is very small compared to other lengths in the problem such as the size of openings. Wave optics, also termed as physic optics is the branch of optics which deals with various phenomenon including diffraction, polarization of light, interference pattern in optics and solved problems, youngs double slit experiment etc. Ray optics geometrical optics covered by lecture introduction to optical modeling the topic of ray optics geometrical optics is not covered in the course fundamentals of modern optics. Light and any other form of electromagnetic wave travels at a speed of c 300,000 kms in vacuum. It is useful to define a quantity called index of refraction n of the medium in which light propagates as the ratio of the speed of light in vacuum to the speed of light in this medium. Geometric optics is when we treat light as a single beam a ray and study the properties. In geometrical optics, light is considered to travel in straight lines, while in physical optics. Wave optics every one of us uses the camera to click photographs, we use sunglasses when we walk out of our house during daytime, also in our car, we have a mirror of a film. They are therefore ubiquitous in several areas of modern optics including polarization manipulations 4, 911, singular optics 1214, and the angular momentum am of light 1519.
In particular, optics is concerned with the generation and propagation of light and its interaction with matter. The most common of these, geometric optics, treats light as a collection of rays that travel in straight lines and bend when they pass through or reflect from surfaces. Splitting of white light containing all wavelengths into color spectrum by. An achromatic lens consists of several lenses made of di. Geometric, physical, and visual optics sciencedirect. Optics is the branch of physics that deals with the behavior of visible light and other electromagnetic waves. Or aan imaginary surface passing through particles oscillating with same phase is known as. Optics is the branch of physics that studies the behaviour and properties of light, including its. It is an experimental fact that light propagates as mutually perpendicular fluctuating electric and magnetic fields according to the mechanism of propogation of transeverse waves. Fermats principle light propagating between two points follows a path, or paths, for which the time taken is an extremum minimum ignoring the wave nature of light basic theory for optical instruments geometrical optics revision. These lessons have been designed to be used as a teaching tool, either as individual lessons or as a series, or they can be used as a revision tool. The speed of light in a medium depends upon the nature of medium.
The wave direction is specified by the normal to the equiphase planes rays 3. Controlling lightwave in riemann space by merging geometrical. What is the difference between physical optics and. Optics notes massachusetts institute of technology. Light waves can be bent and reflected to form new and sometimes altered images. The reason that geometric optics works well here is that a ray stands for essentially a plane wave i. A upright, magnified and real b upright, the same size and virtual c inverted, demagnified and real d inverted, magnified and virtual. In fact, the full description of light as a wave can be rather cumbersome. Recall that a wave front is a locus of points along which all phases and displacements are. As a becomes large, we see that the minima will merge together. Figure 41b shows the same disturbances traveling away from point a the cork as a series of successive wave fronts labeled crests and troughs.
If the lm is close to i, the blurring will be small, and if its far away, there will be a. The ray aspect of light list the ways by which light travels from a source to another location. Wave optics wave front the wave front at any instant is defined as the locus of all the particles of the medium which are in the same state of vibration. All these are nothing but the applications of the wave optics. According to wave theory of light, the light is a form of energy which travels through a medium in the form of transverse wave motion. Splitting of white light containing all wavelengths into color spectrum by a prism. But when size of obstacle or opening is comparable. Geometrical optics for over 100 years, from the time of newton and huygens in the late 1600s, until 1801 when thomas young demonstrated the wave nature of light with his two slit experiment, it was not clear whether light consisted of beams of particles as proposed by newton, or was a wave phenomenon as put forward by huygens. Pdf controlling lightwave in riemann space by merging. However, by merging to and geometrical optics, we present a concept of space wave channeling metamaterial swcm to manipulate backward and forward scattered waves simultaneously. In our discussions of geometric optics we completely ignored the fact that light can also behave as an electromagnetic wave. Object and image the source will produce a circle of light on the lm.
Geometric and wave optics by introduce the basic principles of geometric and wave optics and appreciate the usefulness of these principles to make our life simpler and convenient. 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. The frequency remains the same as light travels from one medium to another. If you capture sunlight in a mirror or lens you can feel the heat where the sunlight is reflectedrefracted as a real image but you cannot feel the heat where the sunlight is. 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. Before we look more closely at the use of light rays in geometrical optics, we need to say a brief word about. Physical optics lecture notes pdf 44p this note covers the following topics. Aberration not included in final exam, supplement pedrotti chapter 20, and for your study only very few optical systems give images that are free from all defects. Damped oscillations when the object is allowed to oscillate in air it takes a long time to stop, and the amplitude decreases very slowly. May 29, 2015 geometric optics is when we treat light as a single beam a ray and study the properties. When an object is placed in front of a plane mirror the image is. Geometrical optics a light source emits light uniformly in all directions of the three. Chapter on chapter on geometrical optics geometrical optics for over 100 years, from the time of newton and huygens in the late 1600s, until 1801 when thomas young demonstrated the wave nature of light with his two slit experiment, it was not clear whether light consisted of beams of particles as proposed by newton, or was a wave phenomenon as. The frequency stays the same as the wave travels from one medium to the other v.
The main propagation direction of the light wave is in the zdirection. When light interacts with smaller objects, it has very prominent wave characteristics, such as constructive and destructive interference. State the principle of superposition and show how it is used to combine two. Geometric and wave optics are two different ways of looking at the phenomenon of light propogation. Sep 28, 2008 geometric and wave optics are two different ways of looking at the phenomenon of light propogation. Eikonal equations, gradient index lenses, hamiltonian optics pdf 11. The energy of the wave travels in a direction perpendicular to the wavefront. What is the difference between physical optics and geometric. Authored by a highly regarded international researcher and pioneer in the field, an introduction to quantum optics.
Plane waves incident on a grating give rise to a set of plane waves, one for each integer solution in. A guide to geometric optics teaching approach in this series we explain geometric optics. Wave can be classified into three types, which are mechanical wave. The course is an introduction to geometrical optics. Optics usually describes the behaviour of visible, ultraviolet, and infrared light. Week 14 rayoptics approach snells law, geometric optics, thin lens, matrix method and light. Problems and solutions for sk2300 optical physics v. Geometrical optics, or ray optics, is a model of optics that describes light propagation in terms of rays. We nd that the wellknown timedelay formula for light generalizes trivially to massive particles. Knowing this, however, is not the same as knowing everything about eyes and telescopes. We only consider the propagation of rays through optical. Towards the end of this book, there is a comprehensive bibliography of books and a few.
This document is highly rated by class 12 students and has been viewed 6068 times. Geometric optics post university of california, berkeley. Physical optics lecture notes pdf 44p download book. Superposition of waves, interference, optical interferometry pdf 1. Physical optics is also the name of an approximation commonly used in optics, electrical engineering and applied physics. Find materials for this course in the pages linked along the left.
Pinhole camera wave optics geometric 12 fermats principle light propagating between two points follows a path, or paths, for which the time taken is an extremum minimum ignoring the wave nature of light basic theory for optical instruments geometrical optics revision geometric. Photon and biphoton physics is a straightforward overview of basic principles. It explained the laws of reflection and refraction of light at an interface. The wave fronts are spherical, and the direction of motion of the wave is perpendicular to the wave front, as depicted in figure. There are problems in which light must be treated as a wave with interference effects.
Optics is the branch of physics that studies the behaviour and properties of light, including its interactions with matter and the construction of instruments that use or detect it. Nasa goddard photo and video, via flickr learning objectives 25. Archimedes and other ancient greek thinkers made original contributions but we mention here heron of alexandria c. Physical optics is a more comprehensive model of light, which includes wave effects such as diffraction and interference that cannot be accounted for in geometric optics. Waves and optics regular waves and optics worksheets and solutions wr1b. But, in physical optics, we consider the wave like. Fortunately, certain defects can be tolerated in a particular application, if the produced images. Geometrical optics can be treated as the limiting case of wave optics when size of obstacle is very much large as compared to wavelength of light under such conditions the wave nature of light can be ignored and light can be assumed to be travelling in straight line rectilinear propagation. In this case, the wavelike properties of light become insignificant as the objects we deal with are very huge as compared to the wavelength of light. Geometric phases, recognized as a universal phenomenon 35 years ago by michael berry 1, 2, play a fundamental role in the interference of vector waves, especially monochromatic optical fields 38. A dynamical theory of the electromagnetic field pdf. But we had learnt all waves have common characteristic properties such as. The cornea is a converging lens located at the outer surface of the eye with fixed focal length approximately equal to 2 cm.
Understanding how light rays can be manipulated allows us to create better contact lenses, fiber optic cables, and high powered telescopes. In geometric optics, we neglect the diffraction effects. Wave optics describes the connection between waves and rays of light. Colors such as these are direct evidence of the wave character of light. So light focusing at a single point is an artifact of the geometric approximations moreover, especially in microscopy, we are interested in resolving object features at distances comparable to to understand light behavior at scales we need to graduate from geometric to the wave description of light propagation, i. The wave packet picture of photons introduced in section 5 of chapter 19 is compatible with treating light as a collection of particlelike photons that follow the rules of geometric optics only as long as the. Spread of the components of a light ray through a prism. Script fundamentals of modern optics, fsu jena, prof.
Properties of light waves light waves are transverse we already know this from em waves amplitude of light wave can mean amplitude of electric or magnetic field component, because they are always proportional ecb but when we speak about amplitude of light waves we generally have electric field component in mind. Nature of light, geometrical optics, optical instrumentation, dispersion, prisms, and aberrations, wave equations, em waves, polarization, fresnel equations, production of polarized light, superposition of waves interference of light, coherence, fraunhofer diffraction, fourier optics, characteristics. We also recover, by way of a hamiltonjacobi equation, the phase. In geometric optics, the following statements are true for real and virtual images. However, people cannot design fantastical optical devices such as invisibility cloaks, optical wormholes, etc. Here v 1 and v 2 are the speed of light in media 1 and 2 with refractive index pp 12 and respectively. Geometric phases are a universal concept that underpins numerous phenomena involving multicomponent wave fields.
Geometric optics problems and solutions in university. Reflection at plane surfaces, reflection at curved surfaces, refraction at plane surface file type. Optics notes topics in these notes are wave properties polarization focal lengths geometrical optics i. In this context, it is an intermediate method between geometric optics, which ignores wave effects, and full wave electromagnetism, which is a precise theory. 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. These polarizationdependent phases are inherent in interference effects, spinorbit interaction phenomena, and topological properties of vector wave fields. It deals with lenses, mirrors, phenomenon of total internal reflection, formation of rainbows, etc etc. Geometrical optics 1 geometrical optics go refers to the simple ray tracing techniques that have been used for centuries at optical frequencies.
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