Autostereoscopic displays provide 3D perception without the need for special glasses or other headgear. Drawing upon three basic technologies, developers can make two different types of autostereoscopic displays: a 2D/3D switchable display, head-tracked display for single-viewer systems and a time- multiplexed multiview display that supports multiple viewers. This study investigated the method of using an autostereoscopic display with a synchro-signal LED scanning backlight module to reduce the crosstalk of right eye and left eye images, enhancing data transfer bandwidth while maintaining image resolution. In the following we introduce how LED backlight and optical film elements are used in autostereoscopic 3D display designs including two-view and multi-view designs. Glasses-free 3D Display Technology, two ways of manufacturing a two-view spatially multiplexed autostereoscopic display. (a) Lenticular: An array of cylindrical lenslets is placed in front of the pixel raster, directing the light from adjacent pixel columns to different viewing slots at the ideal viewing distance so that each of the viewer's eyes sees light from only every second pixel column. (b) Parallax barrier: A barrier mask is placed in front of the pixel raster so that each eye sees light from only every second pixel column. Lenticular lens technology chiefly involves adding periodic arrays of lenticular lens to the outside of a general display. The design must be optimized in accordance with viewpoints and pixel size in order to produce images that can then be transmitted in varying directions. Since each sub-pixel occupies a different position, its off-axis distance to the lenticular lens will vary. With proper design, parts of the sub-pixels can appear in distinct viewpoints. 3D display can then be realized by employing pictures or images taken at these different viewpoints. Since this technology creates parallax through lens optics, which provides a very high optical efficiency, the only brightness loss comes from interface reflection, lens material transmittance, and light scattering. A parallax barrier is a device placed in front of an image source, such as a liquid crystal display, to allow it to show a stereoscopic image without the need for the viewer to wear 3D glasses. Placed in front of the normal LCD, it consists of a layer of material with a series of precision slits, allowing each eye to see a different set of pixels, so creating a sense of depth through parallax in an effect similar to what lenticular printing produces for printed products. A disadvantage of the technology is that the viewer must be positioned in a well-defined spot to experience the 3D effect. Another disadvantage is that the effective horizontal pixel count viewable for each eye is reduced by one half; however, there is research attempting to improve these limitations. A novel time-multiplexed autostereoscopic multi-view full resolution 3D display is proposed. This capability is important in applications such as cockpit displays or mobile, portable, or laptop systems where brightness must be maximized but power conserved as much as possible. The effects are achieved through the creation of light line illumination, by means of which autostereoscopic images are produced, and by simultaneously concentrating the light emitted by the display toward the area the viewer's head is. By turning different illumination sources on and off, it is possible to aim both the concentration area and the 3D viewing area at the observer's head as the observer moves. A variation on the system allows two or more persons to be tracked independently. Cross talk (ghosting) can be reduced to the point of imperceptibility can be achieved. © 2012 by Nova Science Publishers, Inc. All rights reserved.
|Title of host publication||Light-Emitting Diodes and Optoelectronics: New Research|
|Number of pages||33|
|Publication status||Published - Aug 1 2012|