Nntypes of lenses physics pdf

Physics 208 lenses and the eye your ta will use this sheet to score your lab. Lens curvature, width, position, type of glass some can be fixed, other vary with focal length, focus e. Spherical lenses problems the physics hypertextbook. A lens which is thinner in the centerthan the edges is. In principle, electromagnetic waves may have any wavelength, from zero to arbitrarily long. Physics 208 lenses and the eye department of physics. This website and its content is subject to our terms and conditions.

They also enable millions of people to see clearly and read comfortably. Kids learn about lenses and light in the science of physics including concave, convex, converging, diverging, focal point, meniscus, and plano lenses. Ancient egyptians, babylonians, and greeks, all had a sense of basic optics. Lenses and depth of field prepared by behzad sajadi borrowed from fredo durands lectures at mit. A convex lens is also known as the converging lens as the light rays bend inwards and converge at a point which is known as focal length. For a converging lens, parallel light rays will converge to a point. These tensegrity structures are very easy to build if you understand the physics behind them. Illustrate the formation of images using the technique of ray tracking. The focal length f of a lens can be found quite accurately by moving an illuminated object infront of a lens so that an image is cast on a screen. There are two types of the lenses which are the convex lens and the concave lens.

Introduction to the different types of camera lenses. You can simply pull to release more string in order to achieve the right balance. After completing this lab, you will be able to explain how lenses work, explain the difference between convex and concave lenses, draw ray diagrams to analyze the image produced by a lens, and. The same sort of rules apply, just with a few modifications. This, too, i shall ignore, except for a brief foray in section 2.

That means we have been playing with lenses for a long time. A concave lens is flat in the middle and thicker at the edges. Another way to classify lenses is by the curve of the glass on each side of the lens. From last weeks lab, re ection and refraction, you should already be familiar with the following terms. The types and uses of lenses in our life science online. Lenses are found in a huge array of optical instruments, ranging from a simple magnifying glass to the eye to a cameras.

Lenses lenses and curved mirrors are optical instruments designed to focus light in predictable ways. Contact lenses work in the same way as glasses, by adding or subtracting wavefront curvature. A study of lenses is very similar to that of curved mirrors. Another name for this type of lens is a negative lens. We imagine that you are working for the xyz organisation, and the apparatus that you are using will be used in a production environment of the organisation by a technician to make measurements of the focal length of a large number of lenses. Three important instances of equation 1, depicted in figure 3, should be kept in mind.

Jun 01, 2011 this website and its content is subject to our terms and conditions. The convex lens is thick at the center and less thickness at the tips, it collects the light rays falling on it, so, it is called the converging lens. Mini physics is a participant in the amazon services llc associates program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to amazon. Keep in mind that for an object to be considered a lens it must be made of a transparent material that has an index of refraction higher than air. Experiments, as well as our own experiences, show that when light interacts with objects several times as large as its wavelength, it travels in straight lines and acts like a ray. They should try to describe any images they form in terms of magnification, upright or inverted, real or. Watch all the video tutorials in the waves topic at s. A telescope with an objective lens with a diameter with a wavelength of light can barely resolve two objects with an angular separation of using.

Image formation by lenses 10th class physics chapter 12. Optical bench, light box, lenses, lens holders, illu minated target object, white screen with scale, mirror. Convex lens and concave lens are two basic types of lenses. Optical bench, light box, lenses, lens holders, illu. Keep in mind that for an object to be considered a lens it must be made of a transparent material. Rays of light that pass through the lens are brought closer together they converge. If youre behind a web filter, please make sure that the domains. They should try to describe any images they form in terms of magnification, upright or inverted, real or virtual. Since f is measured in metres m the units of lens power are m1. A lens is a transmissive optical device that focuses or disperses light beams by means of refraction. Sep 24, 2015 the lenses are used in microscopes which are used for formation magnified images of the tiny bodies that can not be seen with the naked eye and they are used in making of medical glasses to treat the vision defects. Diverging lenses produce only virtual images of real objects. Lenses concave and convex apparatus selection of lenses, collimated light source, e. Tes global ltd is registered in england company no 02017289 with its registered office at 26 red lion square london wc1r 4hq.

Tes global ltd is registered in england company no 02017289 with its registered office. We shall supply a scenario for the lens optics experiment. F f a diverging lens is one that refracts and diverges parallel light which appears to come from a virtual focus in front of the lens. Electromagnetics, waves, and optics for most people, the nearest distance that objects can be located away from the eye and still seen clearly is. Lenses are one of the most important components in cameras. Use the lensmakers equation to determine the focal length of a thin lens. Lenses lenses are made of transparentmaterials, like glass or plastic. Weve talked a lot about mirrors, in particular parabolic mirrors, that reflect light.

After being given the radius of curvature for this lens, were asked to determine certain properties of the image. If youre seeing this message, it means were having trouble loading external resources on our website. Jun 05, 20 lenses lenses are made of transparentmaterials, like glass or plastic. Isaac physics a project designed to offer support and activities in physics problem solving to teachers and students from gcse level through to university. A more specialized form of lenses, spectacles appeared around the 12 th century, but it took until contemporaries of galileo and later newton to develop a decent telescope we should all like lenses. Since a virtual image cannot be obtained upon a screen, it is necessary to use some indirect method for obtaining the focal length of a diverging lens. Jan 11, 2018 the two main types of lenses in physics concave and convex lenses can be represented by the two symbols in this video tutorial. After passing through the lens the rays ap pear to come from the virtual focus at f. View lab report physics 2 lab report 7 focal length of lenses from physics 2 at howard university. A lens can focus light to form an image, unlike a prism, which refracts light without. Physics 30 lesson 9 optics thin lenses refer to pearson pages 677 to 681. Ray tracing is the technique of determining or following tracing the paths that light rays take. However, while mirrors involve reflection, lenses involve refraction. The two main types of lenses in physics concave and convex lenses can be represented by the two symbols in this video tutorial.

A very commonly used optical device is the thin lens. Rays parallel to the principal axis are diverged by the diverging lens. Nuclear reactions nuclear reactions involve two or more. In this question, were presented with a scenario in which an object is placed a certain distance in front of a thin convex lens. Chapter 36 lenses a powerpoint presentation by paul e. By taking readings of image and object distances for different positions, a graph can be drawn. Physics 2 lab report 7 focal length of lenses focal. Looking through both lenses, using the 10cm lens as an eyepiece lens, view a distant object through both lenses. What does a negative image distance indicate for a mirror and lens what does a negative focal point indicate for a mirror and lens what does a negative image height indicate for a mirror and lens what does a negative magnification indicate for a mirror and lens. Lenses remembering the basics of mirrors puts you half ways towards fully understanding lenses as well. In this section, we will use the law of refraction to explore the properties of lenses and how they form images. Gently adjust the eyepiece lens position until the image of the object is clear and focused.

A diverging lens will cause light rays from a specific focal point to be spread out. With a converging lens, paraxial rays that are parallel to the principal axis converge to the focal point, f. Start by measuring the properties of a thin perhaps biconvex lens. Physics lenses are curved glasses or transparent materials. I am having trouble understanding what signs mean in regards to lenses and mirrors. Physics lens physics education resources, simulations. Initially, i shall also make the approximation that lenses are thin. The term thin is, of course, qualitative, and just means in this sense that we can ignore. Each of a lens two faces is part of asphere and can be convex or concave if a lens is thicker at the center than theedges, it is a convex, or converging, lenssince parallel rays will be converged tomeet at the focus. A convex lens is a converging lens when parallel rays of light pass through a convex lens the refracted rays converge at one point called the principal focus. While light striking a curved surface is more complicated than the flat surfaces we have looked at already, the principle is the same.

If playback doesnt begin shortly, try restarting your device. A lens is a curved piece of glass or plastic designed to refract light in a specific. First, when p q, then both the object and image are 2f from the lens. Some examples of using the thin lens equation with multiple lenses. Another name for this type of lens is a positive lens. The aim of this package is to provide a short self assessment programme for students. Tippens, professor of physics southern polytechnic state university a powerpoint presentation by. Multiple lens systems geometric optics physics khan academy. Alevel physics advancing physicslenses wikibooks, open. Lecture 18 geometric optics ii thin lenses unm physics and. Convex converging lenses can form either real or virtual images cases 1 and 2, respectively, whereas concave diverging lenses can form only virtual images always case 3. The focal length, f, is the distance between f and the lens. Table 1summarizes the three types of images formed by single thin lenses. The lenses are used in microscopes which are used for formation magnified images of the tiny bodies that can not be seen with the naked eye and they are used in making of medical glasses to treat the vision defects.

May 09, 2017 hello guys our lesson today about types of lenses enjoy with physics. Investigate the relationship between power and focal length. From last weeks lab, reflection and refraction, you should already be familiar with the following terms. We will see that lenses can form virtual or real images. When you focus a camera, you adjust the distance of the lens from the film. Lenses in optics applications types of lenses physics. Any given light ray only strikes an infinitesimally small portion of the lens or mirror, and this. Lenses of many different types are used in optical devices such as cameras, eyeglasses, microscopes, telescopes, and projectors. These two types of lenses a double convex and a double concave lens will be the only types of lenses that will be discussed in this unit of the physics classroom tutorial. A simple lens consists of a single piece of transparent material while compound lenses consist of several simple lenses arranged along with a common axis. Use one of the red lenses as the microscope objective to form an image of the light. To avoid this, cancel and sign in to youtube on your computer.

Videos you watch may be added to the tvs watch history and influence tv recommendations. A convex lens is a converging lens when parallel rays of light pass through a convex lens the refracted rays converge at one point called the principal focus the distance between the principal focus and the centre of the lens is called the focal length. In fact, for lenses there are two refractions one when the light ray enters the lens and one when the light ray exits the lens. The apparatus will be in the classic configuration of object, lens and image. Lenses lenses refract light in such a way that an image of the light source is formed.

Overall, then, the formula relating the curvature of the wavefronts leaving a lens to the curvature of the wavefronts entering it is. The focus of convex lenses is where rays parallel to principal axis go. What i want to do now is talk about lenses, or talk about what a lens is. Lenses are found in a huge array of optical instruments, ranging from a simple magnifying glass to the eye to a cameras zoom lens. Convex lens converging concave lens diverging convex lenses are thick in the middle and thinner at the edges. This basically adjusts where the focal point of light entering the eye is, glasses and contact lenses are designed to adjust it so that the focal point of the light lies on the retina. Then repeat the measurements for the spherical and hemispherical lenses. A more specialized form of lenses, spectacles appeared around the 12 th century, but it took until contemporaries of galileo and later newton to develop a decent telescope. Two prisms can bend light toward the principal axis acting like a crude converging lens but. To measure and compare the focal lengths of some lenses using different methods, and to determine the magnification of a simple telescope. The physics convex lenses are converging lenses, and concave lenses are diverging lenses. Even though the image making happens inside the camera body and on the film itself, the lens is what handles the light and determines the quality of the resulting image. Using a ruler or other straight edge and the ray tracing methods described in this section, locate and draw the image of the pencil. This lab closely follows lab l4 in the physics 208 printedonline.

Make the two strings exerting the downward tensions easy to adjust by using technic pins to stick them into bricks with holes. And think about how they transmit or refract light. The separation distance between the two objects, we will call this, and the distance to the objects from the telescope objective can be related to the tangent of that angle, you are far away from the lights and this angle is very. Convex lenses, geometrical optics from alevel physics tutor.