Samsung prototypes with flex screens

Samsung has perfected the OLED/AMOLED technology to create flexible screens on a plastic support. They expect a revolution in the cellular phone design starting next year, when the new screens will show up in latest cell phone models at the end of first half 2013.

This technology is not new, at least 10 years old, but so far only prototypes have been made. The big challenge is to mass produce this kind of screens. Now it seems that Samsung has managed to find a way to do this.

Based on Samsung reports the screens will fit a smart phone form factor, bigger screens that might be used for tablets are not planned for the time being.

Flexibility in the screen decreases the possibility of damaging it when your cell phone hits the floor, are lighter than screens made of glass and may help in lowering production cost,  but it also enables a whole new set of design. So I am really curious to see what designer will come up with ….

The display market is flooded today by LCD, with a limited share of Plasma and an even more limited share of OLED. The dimension of the pixel in plasma screens limits their application to very large display and the production cost (and limited life span) of OLED limits their use in some top of the line cell phones.

NED, Nano Emissive Display are ready, in the labs, but are still years away and probably they will have their time as 4k screens will come to be an object of desire with an affordable price, probably in the second part of this decade.

The Quantum Dot display engineered by Samsung

Now Samsung has shown that the Quantum Dot technology can be transformed into real display, as reported in a recent paper in Nature Photonics, summarized by Technology Review.

Quantum Dot displays promise to be brighter than current LCD (therefore better to see in a lighted environment) and to consume 1/10 of the energy.

Presently their life time is estimated around 10,000 hours (a bit too short, however remember that the first plasma screens had a lifetime of 5,000 hours) and their consumption is about the same of today’s LCD.

One interesting aspect is that they can be created on plastic film, therefore can be bendable. Imagine using them as labels on tomato cans! Quite away in time but we have seen how fast technology can progress.

The real challenge, as experience shows, is the huge volume of LCD production that is leading to continuous, even though linear, innovation. They keep getting better and it is difficult for any underdog technology to take their place.

Organic Light Emitting Displayis a technolgoy that has been around for some time. It provides bright colors using a fraction of the energy required by LED. BUT…it is very difficult to fabricate large screens and therefore, so far, it has only found application in cell phones displays.

Bright colors visible under the Sun light: a dream coming true?

Now a start up company, QD Vision, is starting to market a new technology based on Quantum Dot that promises to be as cost efficient as OLED, to deliver even brighter colors and to support large screens fabrications. An agreement with LG has just been announced: http://www.qdvision.com/content1438.

Quantum Dot technology creates nanoparticle that are sensitive to light at different frequences and that behaves as conversion filters. Infrared emission, that accounts for 80% of a classic light bulb emission (and for the generated heath) can be converted through quantum dot to red, visible light. Depending on the size of the “dot” a specific light frequency is emitted. This allows a dramatic increase in brilliance (no energy is wasted) and lower consumption. The trick is the accurate fabrication of dots with exactly the right size to produce the desired color. This is what QD Vision has managed to achieve.

Take a look at this video explaining it. It is lengthy, 7 minutes, but interesting.

In this decades we are going to see a tremendous increase in the use of screens, we will find them everywhere and on most objects. This will change the way we relate to objects and as a side effect it will increase the bandwidth demand on telecommunications networks.

Researchers at the Fraunhofer Institute, http://www.ipms.fraunhofer.de/en/, have developed a screen technology that is able to display images (as you would expect from a screen) and also detect what is going on in front of the screen. Click on the link for details:

http://www.technologyreview.com/computing/22754/

OLED has made the progress it promised in terms of production yield: it is now economically feasible to produce large OLED screen, up to 42” at a reasonable cost. OLED delivers much better colour quality, has lower energy consumption than a normal LDC (and Plasma) and it is much brighter. So why is it that we find OLED screens on some cell phones but very little in television screens?

The reason is similar to the failure of NED to reach the market. The explosion of flat screens has driven production cost down much more than expected (only 4 years ago the forecast was for a 40” LCD to have a market price around 3000$, now it is down to 1000 $); besides, several innovations have led to bettering of colour (by extensive use of software), better contrast and brightness and at the same time solutions to decrease power consumption are appearing. The new line of backlight illumination based on LEDs is driving energy consumption down since illumination is provide just where it is required (like in Plasma screens) and at the same time this delivers higher contrast.

The other advantage of OLED, a thinner screen, has also been met by conventional LCD screen. The new Sony is just 9.9 mm thick (if calling it thick still makes any sense…)-

There is simply very little incentive for a manufacturer to invest huge amount of money to deploy the infrastructure that would surely deliver a better product but may not lead to significantly greater revenues.  Infrastructures… sound familiar, doesn’t it?

There are also other technologies ready on the labs’ benches that can deliver better image quality and much better resolution. One is the quantum dot display. Here the colour of the pixel is given by the different size of the nano-particle (9nm for a red colour, compare this size with the 300,000 nm of an LCD pixel!  Notice however that we need several of this quantum dots to achieve a comparable brightness, still the gain in resolution is obvious…).

Electronic paper, on the contrary, is very far to compete with the other technologies for high resolution display. It is an interesting technology for reading eBooks on the beach, since it reflects the sun light and the more ambient light available the better the contrast and reading ease. It is not suited for providing a large colour gamut nor high resolution.

On photographic paper the minimum resolution depends on the smallest droplets of ink that can be deposited on the paper (inkjet, thermal, laser,….they use different techniques but for the sake of defining resolution we can stick to the droplets of ink…).

Resolution on video depends on the smallest size that a single pixel can have. Plasma has relatively bigger pixel size than LCD. This is why we don’t have plasma used in screen below 30”. 6 million pixels (what is needed for an HD TV- 2 million per red, blue and green) simply won’t fit.

New technologies like OLED and Nano Emissive Display (NED) can have much smaller pixel size (NED can be as small as 1/300 of an LCD and would be ok for  delivering much higher resolution than today’s screen.

Although OLED technologies can increase resolution to over 150 dot per inch it is only with nanotech that we can get closer to paper resolution (we can reach 500 dots per inch, whilst with paper we can exceed 1000 dots per inch; however since our eye is not able to appreciate any resolution over 300 dots per inch we can say that nanotech would be indistinguishable to us from paper).

When will we see NED screens?  The first screen based on this technology was a 5” prototype produced by Motorola in 2005.

Samsung and Sharp have been working on this technology, originally slated to appear on the mass market this year. Why it is not here as promised?

The reason is simple: the main motivation to produce NED screen was not resolution but lower production cost. The diffusion of LCDs and Plasma has driven cost down so much that this incentive is no longer there.

Higher resolution screens would be of interest to the market but we are missing the transmission technology that would bring content in Ultra High resolution to the screen.

Now the situation may change, thanks to multimegapixel digital camera but the market is too small, today, to convince video manufactures to invest billions of $ in this area.