Small, Steady Steps for AS Displays

The bulk of the 3D displays on the Display Week 2013 exhibit floor were small autostereoscopic (no glasses) LCDs.  Most were unsurprising, but left-right crosstalk is improving on average, and some of the displays were based on native-FHD (1920 x 1080), which does a lot for the quality of the autosteroscopic image if the other engineering details are taken care of properly.

Here are a couple of the more interesting small AS-3D displays on the show floor last week:

NLT Technologies, formerly NEC LCD Technologies,  was demonstrating its multiview AS-3D HxDP displays in which the horizontal sub-pixel density is x times that of the vertical subpixel density.  In addition, each of the red, green, and blue sub-pixels are arranged in rows instead of the traditional columns.  The arrangement, an extension of the company's HDDP (Horizontally Double-Density Pixels) arrangement, can display both 3D and 2D images simultaneously by simply changing the input data.  And, says NLT, it displays "perfect 2D images" without 3D/2D switching, as well as delivering multiple views without reducing the display's native resolution.

NLT showed a 7.2-inch HDDP 2D/3D prototype with viewing angles of 80/80 horizontally and 80/60 vertically, a contrast ratio of 600:1, and a luminance of 370 nits.  In addition, the display incorporated glass lenticular lenses instead of polymer.  The result, said Engineering Manager Bob Dunhouse, is less left-right cross-talk because glass is more dimensionally stable under prolonged heating by the backlight than is polymer.  The claim was supported by a side-by-side comparison and an analysis that showed that the Qualified Binocular Viewing Space (QBVS) of a display with the glass lens is twice that of conventional displays. 

Innolux showed a 4.5-inch 2D/3D display with 1280 x 720 pixels in 2D and 640 x 720 in 3D.  Luminance in 2D was 450 nits and 225 nits in 3D.  The interesting thing about the display was that it could show a 3D image in both landscape and portrait modes simply if you rotated it 90 degrees.  The display used a 2D/3D switchable barrier.

Next, on the Innolux counter, was a similar display with eye-tracking.  The angular range over which the eye-tracking 3D worked was rather limited, but an icon in the corner informed you when you had left the active range and the image had automatically defaulted to 2D.

It is clear that eye-tracking is the way to go for larger, single-user displays, but is it needed for a hand-held display in which the user can readily – even unconsciously – adjust the angle of view with a slight rotation of his or her hand? –Ken Werner

I-Zone Highlight: HoloVizio Lightfield Display

The most interesting 3D display at SID's Display Week was shown in the I-Zone, the area of juried table-top exhibits for prototypes and innovative demonstrations.  Space is free to the winning exhibitors, thanks to the sponsorship of E Ink and the efforts of the volunteers on the selection committee.

The device in question is the HoloVizio Model 80WLT lightfield display made by Holografika Kft. in Budapest, Hungary.  The display has 80 projection engines, each producing a 720p image, according to Holografika CTO Peter Tamas Kovacs, but the image appeared to have considerably less resolution than 720 lines. Kovacs said that may have been the result of misalignment produced in transit.

The display is driven by 4 GPUs contained in two computers that sit inside the display's pedestal, and that were connected to the display with 20 dual-DVI cables. Ideally, said Kovacs, you would like to have each of the 80 projection engines showing an independently captured image, but a studio session with 80 video cameras is not realistic.  So, the company uses four cameras and synthesizes the 80 separate views from them.

The result of this heavy-duty video processing is a 3D display with 180 degrees field of view and continuous motion parallax that permits the viewer to "look behind" elements of the image.  The 3D image is viewable from any position in front of the display; there are no dead zones.

The 80WLT is available for €60,000 by special order.  –Ken Werner

Wearable Touch

Certainly the usual suspects for impressive OLED products did not fail to deliver at this year’s Display Week exhibition, with LG’s OLED TVs and also a whole range of new Samsung Galaxy 4 devices at the show. However, there was also an unexpected exhibitor showing the audience in a very impressive setup what this technology can do.

The Japanese manufacturer Futaba showed various OLED devices that illustrate the broad potential of the technology. One demo showed an OLED watch based on a flexible passive matrix display, which also featured  touch functionality that visitors could try out themselves. But also some transparent PM OLED displays and other flexible display elements were on display and those devices will seemingly go into production in the near future.

Where will those products find their applications?  It seems Futaba is targeting automotive applications first, something that could make a lot of sense especially as the flexibility, transparency and touch features could enable some really interesting new solutions. The low information content of the PM technology should not have strong negative implications in the automotive environment. –Sven Murano

Renesas Brings Pro-Cap In-House

Earlier this week, ID roving reporter Geoff Walker posted here about the shifting relationship between display makers and touch module makers (“The Battle between the Display Makers and the Touch-Module Makers Intensifies.”) In short, many display makers are becoming touch-module makers as well, bringing the process of adding touch capability to their products in-house.

A case in point is Renesas Electronics America, which introduced an extensive line of pro-cap-enabled modules at this year’s Display Week. This is the first time that Renesas has offered in-house pro-cap, for which it performs its own optical bonding and develops its own sensors. The company’s customers, with applications including medical, industrial, kiosk, and in-flight, have been asking for this capability, according to Renesas representatives, and there’s an obvious financial benefit to the do-it-yourself approach. – Jenny Donelan

Silver Nano 2.0

Cima NanoTech made the first public announcement this week of what I like to think of as “silver nano 2.0.” By that I mean that Cima’s product is a “second generation” of silver-based transparent conductor, potentially surpassing Cambrios Technologies’ original (1.0) silver nanowires that were first shipped in 2011. Except that it’s not nanowires; it’s a self-assembling silver mesh made from a liquid containing silver nanoparticles.

Cima’s product, named SANTE, is an entirely new form of transparent-conductor film aimed at replacing ITO in p-cap touchscreens. (SID named it one of four Best in Show winners on Wednesday, May 22.) It starts with an opaque liquid that’s coated on PET, PC, glass, or any other substrate using industry-standard roll-to-roll film-coating equipment. Within 30 seconds, the liquid dries into a mesh consisting of 200-300 micron open spaces with 3-to-5 micron connecting conductors (see the figures below). The transparency and sheet resistivity of the film are fairly competitive with those of (typically) copper-based metal mesh, which means the film offers better performance in both areas than silver nanowires. Since the mesh openings are randomly shaped, there is no relationship between the LCD pixel structure and the silver mesh pattern. This means that unlike with metal mesh, there is no possibility of moiré patterns and the sensor layout can be designed (or modified) by the touchscreen module-supplier rather than the touchscreen controller-supplier. The mesh can be patterned into drive and sense electrodes using conventional wet (chemical) or dry (laser) etching.

In addition to the touchscreen market, Cima is also planning to use different formulations of the product to address the EMI shielding, transparent heater, photovoltaic, OLED lighting, and flexible-electronics markets. First shipments of the touchscreen film are planned for 3Q-2013. – Geoff Walker

There’s More Than One Way to Roll a Display

Few display prospects are more tantalizing than a flexible display that you could roll up like a window shade. It would be like having a projector and retractable screen, except that you don’t need the projector. And while we see enticing demonstrations of displays on plastic films and other novel designs, the prospect of a commercial product always seem to recede just out of reach.

But you don’t need to have a display that is flexible in both directions in order to roll it up. Consider the SHiPLA from Shinoda Plasma of Japan. This is a product that is already commercially available, and it was on display in the I-Zone in the Exhibit Hall at Display Week. (In fact on Wednesday May 22 it won SID’s award for Best Prototype.)

How can you roll up a plasma screen? This would be difficult with a traditional flat panel design. The SHiPLA is actually made of tiny tubes of glass that are individual plasma displays. The module shown in the I-Zone has tubes that are just 1 mm in diameter, though a company representative indicated that 0.5 mm tubes are in development. The tubes are filled with red, green, or blue phosphor and grouped side-by side in threes to create white pixels.

The tubes are arranged horizontally. While the tubes cannot bend, the carrier on which they are mounted is flexible, so the entire mat of tubes can be rolled, just like a bamboo window shade.

This display runs counter to preconceived notions about plasma in other ways. Plasma panels are heavy, not that bright, and power hungry, right? Not this one. The screen weighs less than 2.2 pounds per square meter and is surprisingly bright. A portion equivalent to a 42-in. flat panel consumes only 100 watts of power.

Currently, the display is marketed for large commercial display installations, but the company’s road map includes plans for smaller roll-up models intended for consumer use in the home. -- Alfred Poor

Photo by Alfred Poor

Building a Better Bathroom Mirror

Several years ago, backlighting manufacturer Global Lighting Technologies (GLT) realized that its expertise in LED edge lighting might be extended to the growing market of general lighting. The company now has a foot each industry, and is showing examples from both at Display Week.

One of its general lighting demos is a ring (looking somewhat like a halo) that uses two LEDs in a circular guide with a diffuser to produce a bright, white light. Possible applications include vanity mirrors, and in researching this product category, GLT’s Brett Shriver found himself in a variety of home goods stores, checking out the potential competition. What he found was generally of “terrible quality,” he says, with cheap diffusers and suboptimal engineering. Backlighting requirements are more stringent than those of general lighting, of course. Still, GLT and other display companies expanding into general lighting ought to be able to raise the standard of living for those of us just trying to get a close shave or apply eyeliner in the morning. – Jenny Donelan