To enhance foveal fixation detection while bypassing the deleterious effects of corneal birefringence in retinal
birefringence scanning (RBS), we developed a new RBS design introducing a double-pass spinning half wave plate
(HWP) and a fixed double-pass retarder into the optical system. Utilizing the measured corneal birefringence from a data
set of 300 human eyes, an algorithm and a related computer program, based on Mueller-Stokes matrix calculus, were
developed in MATLAB for optimizing the properties of both wave plates. Foveal fixation detection was optimized with
the HWP spun 9/16 as fast as the circular scan, with the fixed retarder having a retardance of 45° and fast axis at 90°.
With this new RBS design, a significant statistical improvement of 7.3 times in signal strength, i.e. FFT power, was
achieved for the available data set compared with the previous RBS design. The computer-model-optimized RBS design
has the potential not only for eye alignment screening, but also for remote fixation sensing and eye tracking applications.