The purpose of this text is to show you how to design of an optical system, using the optical design program, CODE V. The complete design process (from lens definition to the description and evaluation of lens errors and onto the improvement of lens performance) will be developed and illustrated using the program. The text is organized so that a student will be able to (1) reproduce each step of the process including the plots for evaluating lens performance and (2) understand their significance in producing a final design.

We chose CODE V because it is a well-regarded, full-featured optical design program that has a command line interface. This text is not a user's manual for CODE V. Synopsys has a set of online reference books for that. Rather, the text starts with a single lens to demonstrate the laws of optics and illustrate the basic optical errors (aberrations) using CODE V. Then, through a series of examples, demonstrations, and exercises, you can follow each step in the design process using the CODE V commands to analyze and optimize the system to meet the required performance specifications. Once the nominal design meets these specs, you can determine a set of tolerances that permits a large fraction of them to be manufactured with an acceptable as-built performance.

Although it is assumed that readers will follow the examples in the text and reproduce the results, you are encouraged to use them as jumping off points for an exploration of the designs. In addition to exercises with answers, we have added toward the end of the text what we call "Explorations": open-ended problems with several possible directions to explore the design space. But this exploration needn't be confined to the final chapters. If there is a design feature or strategy that piques your curiosity and you want to find out what happens when you make a change in the design, go ahead and explore the consequences. You can't break anything. However, remember to save your lens before you begin to tinker with things.

This text is written for a student to continually interact with CODE V. Although any commercial software can provide the tools to enter and modify designs, each program has its own interface and command syntax, and it is not possible to demonstrate important optical principles with every worthwhile program in a single text. For those who do not have immediate access to CODE V, there are two possible ways to use this text. If you're connected with a college or university, there are arrangements for students to use CODE V for a modest fee for a limited time. For those who have access to other design programs, the operations and data entry may differ, but most of them will contain the same plotting, evaluation, and optimization functions as CODE V. So, with some translation, it should be possible to demonstrate the same operations as those used in this text.

We hope that this text will engage your curiosity and provide directions that will encourage you to work through all of our examples and then continue exploring optical design on your own. Designing optics is much like a game, where the rules are laid down by the laws of physics; the pieces are surfaces, air spaces, and glass; aberrations are obstacles to be overcome; and the goals are set by the practical requirements of a design. Have fun playing!