<p>You could soon watch 3D videos on your smartphone without any special eyewear, thanks to scientists who have developed a way to make displays for small screen devices that offer both 2D and 3D imaging.<br /><br /></p>.<p>For eyewear-free displays, the only action is behind the screen where the image's pixels and optics are layered together to produce the stereoscopic effect.<br /><br />The two primary ways of producing these optically illusive effects are by using either an array of micro-lenses, called lenticular lenses, or an array of micro-filters, called parallax barriers, in front of the image to make its appearance depend on the angle at which it is being seen.<br /><br />The simplest example of this effect is found on a movie poster whose image appears to change as you walk by.<br /><br />Two or more images are interlaced and printed behind a plastic layer with grooves matching the interlaced pattern.<br /><br />The grooves act as distinct, interlaced arrays of lenses or filters, unveiling one image as you approach the poster and another as you depart.<br /><br />In the case of 2D/3D convertible screens, these layers are active, meaning they can be switched on or off.<br /><br />The gap distance between the image layer and the barrier layer is a key determinant of the viewing distance. Closer stacking of these layers together allows for a closer viewing distance.<br /><br />Sin-Doo Lee, professor at Seoul National University in South Korea, and colleagues developed a monolithic structure that effectively combines the active parallax barrier, a polarising sheet and an image layer into a single panel.<br /><br />Instead of two separate image and barrier panels, they use a polarising interlayer with the image layer in direct contact with one side of the interlayer, while the active parallax barrier of a liquid crystal layer is formed on the other side as an array of periodically patterned indium-tin-oxide (ITO) electrodes.<br /><br />The use of this interlayer allows the minimum separation of the image and barrier layers, thus providing the short viewing distance required for the smaller screens of mobile devices.<br /><br />"The polarising interlayer approach here will allow high resolution together with design flexibility of the displays, and will be applicable for fabricating other types of displays such as viewing-angle switchable devices," Lee said.<br /><br />"Our technology will definitely benefit display companies in manufacturing low cost and light weight 2D/3D convertible displays for mobile applications. Under mobile environments, the weight is one of the important factors," Lee added.<br /><br />This concept not only applies to LC-based 2D/3D displays, but also to OLED-based 2D/3D displays, offering application to a broad range of present and future device designs.<br />The research appears in the journal Optics Express.</p>
<p>You could soon watch 3D videos on your smartphone without any special eyewear, thanks to scientists who have developed a way to make displays for small screen devices that offer both 2D and 3D imaging.<br /><br /></p>.<p>For eyewear-free displays, the only action is behind the screen where the image's pixels and optics are layered together to produce the stereoscopic effect.<br /><br />The two primary ways of producing these optically illusive effects are by using either an array of micro-lenses, called lenticular lenses, or an array of micro-filters, called parallax barriers, in front of the image to make its appearance depend on the angle at which it is being seen.<br /><br />The simplest example of this effect is found on a movie poster whose image appears to change as you walk by.<br /><br />Two or more images are interlaced and printed behind a plastic layer with grooves matching the interlaced pattern.<br /><br />The grooves act as distinct, interlaced arrays of lenses or filters, unveiling one image as you approach the poster and another as you depart.<br /><br />In the case of 2D/3D convertible screens, these layers are active, meaning they can be switched on or off.<br /><br />The gap distance between the image layer and the barrier layer is a key determinant of the viewing distance. Closer stacking of these layers together allows for a closer viewing distance.<br /><br />Sin-Doo Lee, professor at Seoul National University in South Korea, and colleagues developed a monolithic structure that effectively combines the active parallax barrier, a polarising sheet and an image layer into a single panel.<br /><br />Instead of two separate image and barrier panels, they use a polarising interlayer with the image layer in direct contact with one side of the interlayer, while the active parallax barrier of a liquid crystal layer is formed on the other side as an array of periodically patterned indium-tin-oxide (ITO) electrodes.<br /><br />The use of this interlayer allows the minimum separation of the image and barrier layers, thus providing the short viewing distance required for the smaller screens of mobile devices.<br /><br />"The polarising interlayer approach here will allow high resolution together with design flexibility of the displays, and will be applicable for fabricating other types of displays such as viewing-angle switchable devices," Lee said.<br /><br />"Our technology will definitely benefit display companies in manufacturing low cost and light weight 2D/3D convertible displays for mobile applications. Under mobile environments, the weight is one of the important factors," Lee added.<br /><br />This concept not only applies to LC-based 2D/3D displays, but also to OLED-based 2D/3D displays, offering application to a broad range of present and future device designs.<br />The research appears in the journal Optics Express.</p>