With a converging lens, paraxial rays that are parallel to the principal axis converge to the focal point, f. The same sort of rules apply, just with a few modifications. When it hits an object, one that is not smooth, the rays will bounce at many different angles. Pdf optical images due to lenses and mirrors researchgate.
Two prisms can bend light toward the principal axis acting like a crude converging lens but cannot create a sharp focus. Surface shape of perfect lens lens material has index of refraction n. However, if the surface is very smooth, the rays will all reflect obeying the law of reflection. Ray 3 passes straight through the center of the lens. This video contains the properties of concave mirror, concave lens, convex mirror and convex lens and also the types of questions, which could be asked fro. 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. With light, if one thinks of light bouncing off an object, it travels in all directions. Use the lensmakers equation to determine the focal length of a thin lens. The purpose of this lab is to introduce students to some of the properties of thin lenses and mirrors. The m ray passes through the middle of the lens with no deflection. In a plane mirror the image is the same size as the object and the same. The focal length, f, is the distance between f and the lens.
Notice that the lines that converge to form the image point are all drawn solid. The refraction at the first surface is balanced by the refraction at the second surface. Now apply the thin lens equation to determine focal length. The primary goals are to understand the relationship between image. Lenses remembering the basics of mirrors puts you half ways towards fully understanding lenses as well. Recall that if the image is on the same side of the lens as the object, then image distance is negative. Concaveconvex mirror and lenses for ssc cgl, chsl, mts. The vision may be corrected in the diagram above by using a a.
It is proven in introductory physics textbooks1 that the image and. The f ray passes through the focal point on the near side of the lens, then leaves the lens parallel to the principal axis. A ray passing through the center of any lens continues in a straight line. Lenses 1 of 5 lens combinations two converging lenses duration. Just as for mirrors we use three rays to find the image from a lens. Find the distance from the object to the lens, and the distance of the image to the lens, by subtracting out the distance from the lens to the eye.
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