Design of Ghost-free Aerial Display by Using Polarizing Plate and Dihedral Corner Reflector Array

A dihedral corner reflector array (DCRA) is an optical system that displays images in the air. It faces a drawback of reduced visibility of the aerial image due to stray light, which is referred to as a ghost. The formation of a ghost can be suppressed by providing a louver; however, this reduces the viewing angle of the aerial image. This study proposes a design of a ghost-free aerial display using polarizing plates and a DCRA. The experimental results verify that the proposed method suppressed the brightness of the ghost to approximately 23% or less compared to using only the DCRA. Additionally, at an observation angle of 45°, the proposed method obtained a brighter aerial image and ghost than the louver method.