Image Formation (Cont.)

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Chapter 36

• Image Formation (Cont.)

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Outline

• Images formed by refraction
• Spherical refracting surfaces
• Flat refracting surfaces
• Sign conventions for refracting surfaces

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Images formed by refraction

• Consider only paraxial rays Rays that diverge
  from the object and make a small angle with the
  principal axis.
• It can be shown that
• Note we must use the sign conventions when
  applying the above equation in different
  situations.

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Sign conventions for refracting surfaces

• Front and back side of the refracting surface
  The front side is the side of the surface in
  which light rays originate. The other side is the
  back side.

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Flat refracting surfaces

• If a refracting surface is flat, then R??, and we
  have
• Note the sign of q is opposite that of p. So,
  the image formed by a flat refracting surface is
  virtual and on the same side of the surface as
  the object.
• If n1 gtn2, the image is formed between the object
  and the refracting surface.
• If n1 ltn2, the image is formed to the left of the
  object.

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Example 36.7

• A set of coins is embedded in a spherical plastic
  paperweight having a radius of 3.0 cm. The index
  of refraction of the plastic is n1 1.50. One
  coin is located 2.0 cm from the edge of the
  sphere. Find the position of the image of the
  coin.

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Example 36.8

• A small fish is swimming at a depth d below the
  surface of a pond. What is the apparent depth of
  the fish?

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Homework

• Ch. 36, P. 1170, Problems 22, 25.