**Compound
Lens**

This screen will let the user compute the characteristics of Conjoined and Separated Lens pairs.

For the **Conjoined
Lenses** the user enters any two of F1, F2 or Ft and the calculator will
compute the remaining field as well and the magnification of each and the total
magnification of the pair. Pressing the lower Calculate will perform the
computation.

For the **Separated
Pair** the user can enter any two values for each of the two lenses Aperture D1 and or D2, the Focal Length F1 and/or F2 or the Focal Ratios fr1 and/or fr2.
Pressing the upper “Calculate” will compute the remainder of the values.

Pressing “Clear” will clear all the values and allow the user to re-enter.