Diffraction, Reflection and Refraction

Diffraction
1. Waves pass through a gap and spread out
  1. Most pronounced when wave length is similar to the gap size
Reflection
1. Angle of incidence = angle of reflection
2. All angles measured from the normal
3. Average uncertainty
  1. If you have two different degrees for the same angle
    1. 80 and 82 the average is 81
      1. Can only be out by 1
        so 1/81 is the average uncertainty
Refraction
1. When light passes from one substance to another it changes speed
  1. This can cause the light beam to change direction
2. Refractive indicies
  1. n = sin(bigger angle)/ sin(smaller angle)
3. When light travels from higher to lower refractive index it bends away from the normal
Total internal reflection and the critical angle
1. Below the critical angle
  1. Reflected ray gets brighter as i increases
2. At the critical angle
  1. The refracted ray disperses into a spectrum with blue closest to the face
    1. Blue Bends Best
3. Above the critical angle
  1. All light reflected from boundary- TIR
4. Uses of TIR
  1. Optical Fibres
  2. Endoscope
  3. Cat's eyes
  4. Reflective clothing

Resource summary

	Created by Bizzie Ascham over 9 years ago