Color transparent screen using planar glass combined with lens array holographic optical elements

摘要

A color transparent screen was designed in this paper, utilizing a planar glass combined with lens array holographic optical elements (HOEs). The lens array HOEs were exposed using two coherent beams, one of which was the reference wave directly illuminating on the holographic material and the other was modulated by the micro lens array. The lens array HOEs can display the images with see-through abilities. Unlike the conventional ones that used the lens array HOEs as the screen solely, planar glass was adopted here as the waveguide. The projecting light was totally internal-reflected in the planar glass to eliminate undesired zero-order diffracted light and realize high system compactness. Colorful display can be realized in our system as the holographic materials were capable for multi-wavelength display. To verify the effectiveness of this method, a color transparent screen incorporating the lens array HOEs and waveguide was designed. Results showed the circular display area with 20mm in diameter and the pixel resolution of 100μm were achieved in the system. This simple and effective method could be an alternative in the augment reality (AR) applications, such as transparent phone and television.