Semester 1 Extra Credit for Unit 1 Test: Ch. 31 Diffraction and Interference The idea that wave fronts from light are made up of tinier wave fronts was originated from the Dutch mathematician and scientist Christian Huygens. Every point acts like a new source of waves from the light. Huygens’ principle states that every point on any wave front can be regarded as a new point source of light. The laws of reflection and refraction can be shown using Huygens’ principle as well. The concept of diffraction occurs when a wave bends in a way other than reflection or refraction. Diffraction occurs to some degree in every shadow. The amount of diffraction depends on the wavelength and the size of the obstruction that casts …show more content…
The experiment used a light of a single color, or monochromatic light, and two closely spaced slits or pinholes. He realized that the bright fringes of light resulted from light waves from both holes arriving crest to crest, creating a constructive interference. He also realized that the dark areas resulted from light waves coming from trough to crest, creating a destructive interference. The interference fringes made were straight lines. This interference experiment demonstrated the wave nature of light idea generated by Huygens 200 years earlier. Interference patterns are not only found as double-slit arrangements, but also as a multitude of closely spaced parallel slits making a diffraction grating. A prism separates the colors of light by refraction while a diffraction grating separates colors by interference. Common diffraction gratings are visible in things like costume jewelry and feathers of …show more content…
This also causes for many different frequencies. The waves of an incoherent light are rampant and out of phase causing them to interfere with one another. On the other hand, a beam of light with the same frequency, phase, and direction is called a coherent light. In this form of light, there is no interference of waves within the beam, and only a beam of coherent light will not spread and diffuse. Coherent light is produced by a laser, or light amplification by stimulated emission of radiation. Many people believe that a laser is a source of energy; however, it is only a converter of energy. Lasers are used in many different fields and can be used in many applications. One of the most impressive versions of the laser is the hologram. A hologram is a three-dimensional version of a photograph produced by the interference patterns of two laser light beams. It contains the whole message or entire picture in every portion of its surface. The two laser beams are actually part of one beam; one part illuminates the object and is reflected from the object to the film and the second part is reflected from a mirror to the film, called the reference beam. It may appear to be an imageless piece of transparent film to a normal person, but its entire surface is made up of a pattern of tiny interference fringes. The diverging