Optical Design Study 3

Double Gauss lens

See Double-Gauss example as a model double-Gauss design.

  1. Design a 50-mm focal length f/2.8 double gauss lens with a half-field of view of 24°. Your merit function shoud use standard wavelengths and fractional fields of 0, 0.7, and 1.

  2. Using the design above as a starting point, design a 50-mm focal length f/1.4 double gauss lens with a half-field of view of 24°.

  3. Using the first lens as a starting point, redesign the lens for a minimum back focal distance of 38.5 mm, required for a 35-mm format SLR camera mirror return mechanism. Compare the change in optical performance (spot size vs field) from the original lens.

  4. Optional: Design a triplet lens in ZEMAX with zero fourth-order aberrations.

For each lens, provide

  1. a full listing of lens data
  2. a drawing of the lens
  3. rms spot size vs. field
  4. focal length vs. wavelength
  5. ray fans
  6. field plot
  7. spot diagrams

Also generate MTF plots at all fields. Compare the MTF plots of the double-gauss to the corresponding triplet lens.

Maintained by John Loomis, last updated 1 July 2011