ABSTRACT

Up to the late 1940s, all optical designs had to be made by hand calculation, tracing rays with a logarithmic table. This method was extremely tedious and slow. Tracing only one ray through an optical system took many hours of work and patience. Lens optimization programs need a starting design to make several iterations until a good design is found. The main problem in lens design is that the functions forming the merit function are not linear. Then, the solution very much depends on the starting point. To approach the solution, several mathematical methods have been used. Even when all the individual damping factors are equal, it is logical to expect that different variables have different effects on the search for a solution. The definition of the merit (or error) function and the boundary conditions are two very important steps in lens design.