Spherical retroreflectors have a much greater acceptance angle than conventional retroreflectors such as corner cubes. However, the optical performance of known spherical reflectors is limited by spherical aberration. It is shown that third-order spherical aberration may be corrected by using two or more layers of homogeneous optical media of different refractive indices. The performance of the retroreflector is characterized by the scattering (or radar) cross section, which is calculated by using optical design software. A practical spherical reflector is described that offers a significant increase in optical performance over existing devices. No gradient index components are required, and the device is constructed by using conventional optical materials and fabrication techniques. The experimental results confirm that the device operates correctly at the design wavelength of 690 nm.
© 2007 Optical Society of America
Original Manuscript: July 11, 2006
Revised Manuscript: October 6, 2006
Manuscript Accepted: October 17, 2006
Published: February 12, 2007
John P. Oakley, "Whole-angle spherical retroreflector using concentric layers of homogeneous optical media," Appl. Opt. 46, 1026-1031 (2007)