A novel (to the best of our knowledge) Fresnel lens array is proposed to realize a uniform directional backlight with two-dimensional directionality. Autostereoscopic display with the proposed lens array improves image output quality and relieves the viewer’s posture restriction without the need for any additional eye aid. In the proposed lens array, tiny prisms composing two adjacent linear Fresnel lenses are interleaved so that the two lenses may be virtually overlapped and work independently. The widths of the elemental prisms vary depending on the distance from the center of each lens. Thus, the light passing through the two lenses is mixed, which results in higher and more uniform luminance intensity. A prototype of an autostereoscopic display based on the time-multiplexed directional backlight method and made with the proposed lens array attained uniform luminance as well as low cross–talk between left-eye and right-eye images.

A novel autostereoscopic display with a directional backlight unit using a pair of inclined interleaved linear Fresnel lens arrays is designed and evaluated. Different high-resolution stereoscopic image pairs are provided to each of the two viewers simultaneously by applying time-division quadruplexing. The viewing zone is enlarged in the horizontal direction by inclining the lens array, which enables two viewers to have specific views corresponding to the positions of their own eyes without interfering with each other’s view. Thus, two viewers with no special goggles on can share the same 3D world, which enables direct-manipulation style interaction and collaboration maintaining eye contact with each other.

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In this paper, an autostereoscopic display system based on a time-multiplexed directional backlight using a large aperture Fresnel lens is proposed. High-resolution stereoscopy for multiple viewers positioned at different distances from the screen is achieved in the proposed system by layering polymer dispersed liquid crystal screens behind the Fresnel lens. The screens with segmented electrodes are electrically controlled to change the position of light diffusion, while the time-multiplexed backlight is projected by a digital mirror device projector at a high refresh rate. The light is diffused at the conjugate focal points of the observers’ eyes to deliver directional light to each eye. The right-eye image and the left-eye image are alternated on the LCD panel in front of the lens to synchronize with the backlight.