Chromatic aberration correction in bi-focal augmented reality display by the multi-layer Pancharatnam-Berry phase lens

Chromatic aberration is a main obstacle for the commercial application of augmented reality displays. The current digital and optical compensation methods of reducing the chromatic aberration suffer from processing time, power consumption or complex design. Here, a simple strategy of chromatic aberration correction in bi-focal augmented reality near-eye display based on multi-layer Pancharatnam-Berry phase lens has been demonstrated and verified by experimental results. The multi-layer Pancharatnam-Berry phase lens, as a part of optical combiner, is fabricated by three liquid crystal polymer phase lenses with central wavelength in red, green, and blue, respectively. The multi-layer Pancharatnam-Berry phase lens can effectively reduce the chromatic aberration in both convex and concave mode of bi-focal augmented reality system, where the color breakup of virtual images captured in bi-focal augmented reality display is significantly alleviated. Comparing to the value of Delta K = 1.3 m(-1) in single green Pancharatnam-Berry phase lens, the multi-layer Pancharatnam-Berry phase lens system significantly reduce the Delta K to 0.45 m(-1) with reduction of 65.4%, which finally decreases the longitudinal chromatic aberration and improve the quality of images. The proposed broadband multi-layer Pancharatnam-Berry phase lens can benefit augmented reality displays and find widespread application in the near-eye displays. (C) 2022 Optica Publishing Group under the terms of the Optica Open Access Publishing Agreement