A 3D display with switchable optimal view distances

Conventional 3D displays have only one optimal view distance (OVD). When observers stay away from the OVD, crosstalk occurs. Therefore, a 3D display with switchable optimal view distances is proposed. The proposed 3D display consists of a scattering modulator, a directional light source array, and a 2D display panel. The 2D display panel is used to provide parallax images. The directional light source array light up the scattering modulator to form a postpositive backlight. The scattering modulator is formed by stacking at least two polymer dispersed liquid crystal (PDLC) layers. One layer in the stack can be set in a scattering state. The others are set in a transparent state. So the scattering PDLC layer will become a postpositive backlight and project parallax images into different spatial directions. Because the PDLC layers in the stack have different distances to the 2D display panel, different OVDs can be provided. A prototype of the proposed display is developed. Experimental results show the proposed 3D display is helpful for crosstalk reduction by switching to suitable OVD.