Reflection of Light in Mirrors

• Mirror - a highly polished surface that is usually made of glass coated with silver or aluminum on one surface.
• Two Types of Mirrors:

  1. Plane Mirrors - flat surface.
  2. Spherical Mirrors - curved mirror.
• Reflection - bouncing back of light into the same medium it had been traveling after striking a surface.
• Incident Ray - ray that stikes the surface.
• Reflected Ray - the ray that rebound from the surface.
• Normal - line perpendicular to the surface at the point of incidence.
• The Angles of Incidence (Øi) - the angle between the incidence ray and the normal.
• The Angle of Reflection (Øf) - the angle between the reflected ray and the normal.
• Types of Reflection:

  1. Specular Reflection - off a smooth surface.
  2. Diffuse Reflection - off an irregular or dull surface.
• Image - reproduction of an original object through the use of light.
• Types of Image:

  1. Real Image - appears in front of the mirror.
  2. Virtual Image - appears behind the mirror.
• Size of Images:

  1. Enlarged - larger than the object.
  2. Reduced - smaller than the object.
  3. The Same - same size as the object.
• Attitude or Orientation of Images:

  1. Upright - right side up.
  2. Inverted (Vertical) - upside down.
  3. Laterally Inverted - flipped horizontally.
• Location of Images:

  1. Behind the mirror.
  2. The same distance.
  3. In front of the mirror.
• Properties of Plane Mirror using S.A.L.T

  S (Size): same size.

  A (Attitude): upright.

  L (Location): behind the mirror at the same distance that the object is in front of the mirror.

  T (Type): virtual image.
• Lens - transparent piece of glass with two refracting surfaces.
• Types of Lens:

  1. Converging or Convex Lenses - thicker at the center.
  2. Diverging or Concave Lenses - thinner at the center.
• Some Common Eye Defects:

  1. Myopia - nearsighted, concave lens.
  2. Hyperopia - farsighted, convex lens.
  3. Astigmatism - a type of refractive error.