Extended optimization of chromatic aberrations via a hybrid Taguchi–genetic algorithm for zoom optics with a diffractive optical element

In this research, we propose a new method, a hybrid Taguchi–genetic algorithm (HTGA), for optics and zoom optics with a diffractive optical element (DOE) in order to eliminate chromatic aberration more efficiently than traditional damped least squares (DLS) does. By researching and validating a set of optical designs using a DOE, we have derived an optimal theory for the specific elimination of chromatic aberrations. Following the advanced technology applied to microlenses and the etching process, precisely made microDOE elements may now be manufactured on a large scale. We adopted the genetic algorithm (GA) and incorporated the steady Taguchi method into it. Combining these two methods produced a new hybrid Taguchi–genetic algorithm (HTGA). Suitable glass combinations and best positions for the DOE, which could not be properly achieved with DLS, were carefully selected to minimize the chromatic aberration in the optical system. We used an optical system with a fixed-focus and complicated 4 × zoom optics with a DOE to compare the optimization results of traditional DLS for optics with a DOE. Experiments show that, whether the chromatic aberration was axial or longitudinal, the values of the measurements involving the chromatic aberration of the optical lens could be significantly reduced.