Ghost Reduction and Brightness Enhancement of Aerial Images Using Lens Diffusers in MMAPs

This paper proposes a new method for improving the image quality of ASKA3D, a product with a micro-mirror array plates (MMAPs) structure that is relatively easy to implement among devices that can image in the air. Conventional technologies have improved visibility by shading ghost light rays generated by stray light, but the shading causes a decrease in luminance. In this study, we proposed a method to reduce ghosting without shading by using collimated light and a lens diffuser. Experimental results showed that the luminance of the aerial image was improved, and the luminance of ghosting was reduced at all angles in the ASKA3D operating range of 0° to 25°, compared with the conventional method using louvers. This enables high-luminance ghost reduction without light shielding.