You can easily remember the directions if you curl e into h with the fingers of the right hand. Geometrical optics please remember to photocopy 4 pages onto one sheet by going a3a4 and using back to back on the photocopier contents. Fermats principle leads to principle of reversibility. R is the radius of curvature and is the distance c from the mirror.
Optics 567 optics formulas light righthand rule light is a transverse electromagnetic wave. Fermats principle is the basis of geometrical optics which ignores the wave nature of light. Introduction to geometric optics geometric optics light from this page or screen is formed into an image by the lens of your eye, much as the lens of the camera that made this photograph. The results determined from the ray diagrams will be compared to the mathematical formulas. A light ray from a source goes in a straight line through the air, but when it encounters a lens, prism, or mirror it bends or changes direction.
We have already studied that the geometric centre of a spherical mirror is called its pole while. Archimedes and other ancient greek thinkers made original contributions but we mention here heron of alexandria c. The electric e and magnetic m fields are perpendicular to each other and to the propagation vector k, as shown below. Use the lensmakers equation to determine the focal length of a thin lens. This workbook is designed to supplement optics textbooks and covers all the traditional topics of geometrical optics. Geometrical optics, or ray optics, is to study the geometry of paths of lights and their imagery through optical systems. As a result, radio telescopes can use sheet metal or even. The wave fronts are spherical, and the direction of motion of the wave is perpendicular to the wave front, as depicted in figure. In most introductory texts, geometrical optics appears after maxwells equations and theory of light. This mirror is a portion of a sphere of radius r whose center is at c.
Light waves can be bent and reflected to form new and sometimes altered images. Set a rightangle prism on one of its parallel sides on a sheet of 11. Geometrical optics a light source emits light uniformly in all directions of the three. Hechts optics not used in this class object distances are positive to the left, negative to the right.
The ray in geometric optics is an abstraction useful for approximating the paths along which light propagates under certain circumstances. When an object is placed in front of a plane mirror the image is. Light 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 action of a simple lens, similar to many of those used in the microscope, is governed by the principles of refraction and reflection and can be understood with the aid of a few simple rules about the geometry involved in tracing light rays through the lens. Learn exactly what happened in this chapter, scene, or section of geometric optics and what it means. It also contains a few examples and practice problems along with the equations needed to solve it. On top of the boring subject that is geometrical optics this book, is the easily the worst text book ive ever had to use, not only are many of the answers wrong, there are numerous typos, the book has little to no examples, its format and setup are very poorly done and on top of all that the index is also terribly lacking.
Three phenomena reflection, refraction, and diffraction help you predict where a ray or rays of light will go. This equation allows you to calculate the focal length of a lens if all you know is the curvature of the two surfaces. Geometrical optics geometrical optics is the treatment of the passage of light through lenses, prisms, etc. Arithmetic and geometricprogressions mctyapgp20091 this unit introduces sequences and series, and gives some simple examples of each.
Types of lenses and mirrors consider reection from a concave spherical mirror, as shown in figure 2. The electric e and magnetic m fields are perpendicular to each other and to the propagation vector k, as shown below power density is given by poyntings vector, p, the vector product of e and h. Geometrical optics, or ray optics, is a model of optics that describes light propagation in terms of rays. In geometrical optics we represent light rays with arrows with straight lines. Deviation, measured in degrees, is the angle an incident ray is turned through after passing through a prismor other optical component. Optics describe the light propagation in terms of the light ray. The part of optics dealing with the ray aspect of light is called geometric optics. There is a certain logic to this, first introducing a basic theory. These lecture notes on geometrical optics is an opportunity to present my experiences.
Prisms, geometrical optics from alevel physics tutor. An optical image may be regarded as the apparent reproduction of an object by a lens or mirror system, employing light as a carrier. A ray of light gives the direction of propagation of light. A upright, magnified and real b upright, the same size and virtual c inverted, demagnified and real d inverted, magnified and virtual. Perfect for acing essays, tests, and quizzes, as well as for writing lesson plans. Understanding how light rays can be manipulated allows us to create better contact lenses, fiber optic cables, and high powered telescopes.
Some of the reasons put forward by students behind this thought were, no. Light rays tend to bend at the interface of two different medium where the refractive index changes. Geometric optics electricity and magnetism heat and thermodynamics physical optics max fairbairns planetary photometry integrals and differential equations. Concave mirrors and convex mirrors ray diagram equations. A summary of geometrical optics in s geometric optics. There are formulas and rules that tell how much the change in direction will be for any circumstance of a ray passing into or out of a medium, lens, prism, etc. Eele 481582 optical design montana state university s15 j. In this module, you will learn about one of the two main divisions of basic opticsgeometrical ray optics. During my interaction with engineering and medical aspirants i, realized that most feared topics in physics is geometrical optics. That is, the normal is along the radius, the line joining the centre of curvature of the mirror to the point of incidence. Light will be treated as a form of energy which travels in straight lines called rays.
Some geometric formula are rather complicated and few you might hardly ever seen them, however, there are some basic formulas which are used in our daily life to calculate the length, space and so on. Optics is the cornerstone of photonics systems and applications. Light can behave in many ways like a wave or a packet of photons which travel in a straight line exhibiting the property of rectilinear propagation. Lenses and geometrical optics florida state university. An object placed a certain distance away from a lens will produce an image at a certain distance from the lens, and the thin lens equation relates the image location to the object distance. Fermats principle is a unifying principle of geometric optics that can be used to derive laws of reflection and refraction, and to find the equations that describe ray. In the module to follow, you will learn about the other physical wave optics. Refraction problems in geometric optics springerlink. Geometrical optics deals with the propagation of light in a straight line and phenomena such as reflection, refraction, polarization, etc. We present a description of the far field and the near field problems for refraction when the source of energy is located at one point.
Reflection and refraction are two processes that change the direction light travels. To read more, buy study materials of ray optics and optical instruments comprising study notes, revision notes, video lectures, previous year solved questions etc. How changing the lens radius, index and diameter effects where the image appears and how it looks magnification, brightness and inversion. This physics video tutorial provides the ray diagrams for a concave and convex mirror. In the figure, a point object at o emits a ray of light along the optical axis, and. To get answer to any question related to iit jee ray optics study material click here.
When a light ray travels from one medium to another, part of the incident. The subject of geometrical optics is the study of the behavior of light. In optics the definite integral is integral of the time required for the transit of the light ray from starting to finishing proper value of x that minimizes the optical path length and keeps it stationary at the vicinity. Chapter 1 handbook of optics photonics research group. In order to quantify the variation of light speed in different medium, we introduce of an index of refraction n.
With these rules and a little geometry, one can construct the whole path of a ray, hence the name geometrical optics. Physical optics lecture notes pdf 44p this note covers the following topics. Mirrors, like lenses, can also form images that in turn are captured by your eye. Based on rectilinear propagation of light valid only if. Ray optics and optical instruments 311 this case is to be taken as normal to the tangent to surface at the point of incidence.
The light ray in geometrical optics is an instrument which is used to approximate models of how the light will propagate. The goal of the experiment is to be able to analyze ray diagrams so as to determine fundamental properties of image formation. Concept questions for physics using phet inquiry based algebrabased physics semester one lessons, clicker questions, and schedule in pdf inquiry based. In the module to follow, you will learn about the otherphysical wave optics. An entire image is generally produced simultaneously, as by the lens in a camera. Other important optics topics include interference, polarization, and fiber optics. It also explores particular types of sequence known as arithmetic progressions aps and geometric progressions gps, and the corresponding series. Light rays are lines which are perpendicular to the lights wavefronts.
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