PHYSICS C10 Lecture Notes - Lecture 16: The Sharper Image, Plane Wave, Near-Sightedness
Document Summary
Visible light: when light goes through a rectangular prism that is tilted at an angle, the light exits parallel to its original direction, but displaced. The incoming and outgoing rays are parallel because the light is refracted at the same angle at each edge. Diffraction: when a plane wave goes through an aperture, it spreads out on the other side, light diffracts just like other waves. Angle at which the light diffracts = /d: resolution is calculated the same way as diffraction. Cameras and telescopes achieve a high resolution by having a very large diameter (d) of the mirror. Wave nature of light: light rays are transverse waves, light is a combination of waves in electric and magnetic fields, which are 90 degrees to each other. Magnification: a positive/converging/convex lens can act as a magnifying glass, a magnifier refracts light from an object into parallel rays that then reach the eye, telescopes and microscopes both use combinations of positive lenses.
