Technology will benefit display companies in manufacturing low cost and light weight 2D/3D convertible displays for mobile applications
Convertible video displays that offer both 2D and 3D imaging without the need of any eyewear offer greater convenience to users who would otherwise have to keep track of yet another accessory. Such autostereoscopic displays have already hit the TV market, but the underlying technology reveals its limitations at close viewing distances. Viewers typically must view these displays from a distance of around one meter (about three feet), eliminating any practical applicability to the smaller screens of mobile devices.
Researchers at Seoul National University, South Korea, however, have developed a new method of making these convertible displays that not only achieved near-viewing capabilities, but also simplified and shrank the architecture of the technology. In a paper published this week in the journal Optics Express, from The Optical Society (OSA), researchers describe their novel design.
For eyewear-free displays, the only action is behind the screen where the images’ pixels and optics are layered together to produce the stereoscopic effect. 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.
The simplest example of this effect is found on a movie poster whose image appears to change as you walk by. Two (or more) images are interlaced and printed behind a plastic layer with grooves matching the interlaced pattern. The grooves act as distinct, interlaced arrays of lenses or filters, revealing one image as you approach the poster and another as you depart, viewing the same poster from a different angle.
In the case of 2D/3D convertible screens, these layers are active, meaning they can be (electronically) switched on or off. 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.
In their paper, Sin-Doo Lee, a professor of electrical engineering at Seoul National University, and his colleagues describe a monolithic structure that effectively combines the active parallax barrier, a polarizing sheet and an image layer into a single panel. Instead of two separate image and barrier panels, they use a polarizing 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.
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.
“The polarizing 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. “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.”
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.
Seoul National University (Acronym: SNU; Korean, 서울대학교, Seoul Daehakgyo, colloquially Seouldae) is a national research university located in Seoul, Korea.
Founded in 1946, Seoul National has served as a model for many national and public universities in the country. Today the university comprises sixteen colleges and six professional schools, and a student body of about 28,000. It has two campuses in Seoul: the main campus in Gwanak and the medical campus in Jongno. According to data compiled by KEDI, the university spends more on its students per capita than any other university in the country that enrolls at least 10,000.
The university maintains an undergraduate exchange program with the Harvard-Yenching Institute, Stanford University, and Yale University. SNU Law School and Harvard Law School students may study at the partner institution for credit. In addition, the university holds a memorandum of understanding with over 700 academic institutions in 40 countries, the World Bank, and the country’s first ever general academic exchange program with the University of Pennsylvania.
The Graduate School of Business offers dual master’s degrees with Duke University, ESSEC, and the Peking University, double-degrees at the MIT Sloan School of Management and Yale School of Management, and MBA-, MS-, and PhD-candidate exchange programs with universities in ten countries on four continents. The university’s international faculty headcount is 242 or 4% of the total. Nobel laureates Paul Crutzen, Thomas Sargent, and Fields Medal recipient Hironaka Heisuke are on the faculty roster.
The Latest Updated Research News:
Seoul National University research articles from Innovation Toronto
- Discovery Could Mean 5 times Longer-Lasting Batteries from Cell Phones to Car Batteries – May 24, 2016
- Bio-inspired robots move without batteries – November 24, 2015
- New optoelectronic probe enables communication with neural microcircuits – October 13, 2015
- Electronic nose can sniff out bacteria in drinking water – September 10, 2015
- Robotic insect mimics Nature’s extreme moves – August 1, 2015
- World’s Thinnest Light Bulb—Graphene Gets Bright! – June 16, 2015
- Scientists Reveal Underpinnings of Drought Tolerance in Plants – June 12, 2015
- QLEDs Meet Wearable Devices – June 4, 2015
- Used cigarette butts offer energy storage solution – May 16, 2015
- Elastic, Flexible Piezoelectric Energy Harvester for Stretchable Electronics – April 14, 2015
- A new kind of vibration sensor could give us ‘Spidey sense’ – December 13, 2014
- Researchers discover breakthrough technique that could make electronics smaller and better
- Korea shows off salad-tossing robot at Robot World 2012
- NEXT GENERATION 3-D THEATER: OPTICAL SCIENCE MAKES GLASSES A THING OF THE PAST
- Soft autonomous robot inches along like an earthworm
- 3-D, Hold the Glasses
- New Glasses-Free 3-D Approach Could Work on Thin, Flexible Displays
This breakthrough highlights new possibilities for integrating high-definition full color displays in wearable electronics.
The scientific team, from the Institute for Basic Science (IBS) and Seoul National University, has developed an ultra-thin wearable quantum dot light emitting diodes (QLEDs). The electronic tattoo is based on current quantum dot light emitting diode (QLED) technology. Colloidal quantum dot (QLED’s) have attracted great attention as next generation displays. The quantum dots (QDs) have unique properties such as the color tunability, photo/air stability, and are printability on various substrates. The device is paper thin and can be applied to human skin like a sticker.
The team developed the high performance red, green, and blue QLED array, whose resolutions approach 2,500 pixels per inch. This resolution is far superior to other light emitting devices and displays on the market today including ones used in the latest smartphones. The technique is readily scalable over large area. Devices are adaptable to deformed states and thereby built on the unconventional curvilinear substrates including surfaces of various objects. Further mechanical deformations, such as stretching or wrinkling, are also adopted in this technology, which enables QLEDs on the human skin. This breakthrough highlights new possibilities for integrating high-definition full color displays in wearable electronics.
Read more: QLEDs Meet Wearable Devices