A case study is presented to illustrate some of the performance and cost driving tradeoffs involved in the design and
tolerancing of optics and optomechanics, where simple lens barrels are concerned. A double Gauss lens was designed,
along with two variations of lens barrel designs for mounting the lenses. The two lens barrel designs are compared, and
one is selected for further analysis. Tolerance selection guidelines are given and discussed for the optics, as well as the
optomechanics. It is shown how the optomechanical tolerances (axial spacing, element decenter, and element tilt) are
derived from their primary parameters for the selected lens barrel design. Finally, Monte Carlo analysis is used, along
with the provided tolerancing guidelines, to determine reasonable tolerances in order to satisfy the optical performance
and yield requirements.