concave lenses

• Concave lens


  Thicker at the edges than the center
• How a concave lens forms an image

  1. Parallel rays of light hitting a concave lens spread out (diverge)

  2. The light rays appear to come from the principal focus (F) behind the lens
• Image formed by a concave lens

  • Diminished (smaller than the object)
  • Right way up
  • Virtual (the rays do not actually cross, they only appear to)
• A screen placed where the image appears will not show the image