Ask Hackaday: Why Don’t We Have Flexible Displays Yet?

A few times a month we receive extremely well crafted crowdfunding campaigns in our tip line that make us doubt our sense of reality. While this article therefore isn’t a hack, we felt it would be a good place to start a discussion around OLED flexible displays.

As the dedicated Wikipedia article states flexible displays have been around for a few years already. In 2013, the Samsung Galaxy Round was unveiled as the world’s first mobile phone with a 5.7″ flexible display. The phone (and the screen) were curved in shape but the phone itself was solid. The same goes for the recent Samsung Gear S smart watch.

Yet for only $350 in a $50k goal crowdfunding campaign the Portal flexible wearable smartphone seems to have all the answers. It is scratch & shatter proof, water-resistant, flexible, includes a ‘Portal proprietary flexible battery’, the ‘Fastest multi-core CPU’, gyro, compass, barometer, Bluetooth 4.0, NFC, GPS…. Specifications are even subject to change to ensure the best available components… and it is 89% funded. As they mention,

building a smartphone or a tech company isn’t rocket science.

We also found a 70% funded €100k crowdfunding campaign for a watch bracelet (right click to translate) that will include GPS, Bluetooth, NFS (not a typo), a uSD card, a 4 lines LED screen and a battery for a few days autonomy… how surprising that no major manufacturer thought of that.

This leads us to the title of this post: why don’t we have truly flexible displays yet? We’ll let our readers discussion this point in the comments section below…

90 thoughts on “Ask Hackaday: Why Don’t We Have Flexible Displays Yet?

  1. I was not aware actual flexible batteries with any sort of usable capacity exist …
    Also i have played with flexible displays at a convention once, there neat but the one i looked at (early in 2014) was not that bright and was transparent (tho futuristic it was super annoying) and you could only flex it so far before it “breaks” … i wonder of the ability of flexible capacitive touch …
    I can see flexible displays being useful to flex displays around a static object in production but some stuff i have heard like a roll-up-able game system and laptops and tablets and such just seems ridiculous to me

      1. The majority of capacitive panels are already quite flexible, however they are optically bonded to glass for a better tactile sensation. Thin LiPo batteries can all ready be flexed to varying degrees with no immediate ill effect ( not sure about the ramifications of long term flexing ) It is possible the creators of Portal are cheating a bit and using multiple tall/narrow cells or even a grid of narrow/short cells. Battery control ICs are tiny & feature rich; handling balancing and charging of even 6 or 8 cells would be trivial.

        1. i have worked in portable power management for almost 2 years and i have only heard 1mAh flexible batteries being created and not for resale just in labs … we have in the past used 10 50mah batteries lined up to create a horizontally flexible 500mAh battery before but charging was a massive bitch (power balancing)

  2. Most large companies seem unable to develop new products on a tight budget, when they think they might bring them to market. It appears as if they strive to ensure that they only have major disasters and not minor setbacks.

    Aside from OLEDs that roll up, into a cigar-size for portability, or wallpaper size… not sure what use flexible OLEDs are. Could make cool raincoats, maybe?

    1. They could for instance curve when worn on a watch then be flat if you take off that watch?

      Or just to have a larger display that you can carry in a small package instead of having to make a choice in either carrying a huge thing or having to deal with a tiny screen.

  3. Even if flexible displays get more robust and cheaper, I imagine there will be trade offs, eg, lower pixel density, lower contrast ratio, worse brightness, etc. How much more would you be willing to pay and how much quality are you willing to give up in order to get flexibility?

    1. Depends on the use scenario I would say. If lets say a military fieldcommander can unroll a larger display to plan tactics in the field, that might be worth some money to the people handling military budgets. Just to name an example of the top of my head.

          1. Imagine you get together with your platoon and you point “the enemy has mounted guns there and there, we can bypass those and initiate an assault *points again* here”. Then a scout says “no we can’t because I saw them plants explosives both *points* here and here”.

            All that kind of thing is needlessly complicated trying to do it on a HUD, you would need a complex gesture capturing system and send it interactively to others and what not. or use a voice recognition and people would have to say coordinates but as the location is zoomed the coordinates would have to be increasingly precise. Seems silly to overengineer really.

            And I’ve seen the real deal where they have screens in their vehicles, so it seems so far they go with screens and save the HUD for aircraft. Although admittedly I have heard they did some field test with some sort of HUD. But if I were a soldier I would find it distracting I expect unless it’s very very well designed, unusually well.

    2. A lot if the use case suits.
      Id much rather have a simple “band” on my wrist then these big smartphone things they are trying to sale us.
      I dont need a color screen, fancy graphics or even that much processing.
      Just enough to read the time, possible text updates, and let it work for NFC and possible health monitoring. Link it to my phone and Id be happy.

  4. Around 2002, I had an idea for a product that would have benefited from a small, flexible display. It didn’t need to flex while bring used, but the ability to wrap around a curved surface was necessary. I did some research and found out that Texas Instruments (i think it was TI) was working on a display technology called Organic Light Emitting Diode and there were videos online showing small, monochrome displays being twisted in someone’s hand while video was playing. I was super excited.

    I was showing those “amazing” video clips to people, I was telling family members how, “you watch, within 10 years, you will be able to carry your TV around in a tube like a poster and unroll it onto the wall.”

    Then a few years ago, (I think it was Sony) debuted a small, 13″ or so OLED TV at CES and it was super thin, but not flexible. I was again, explaining how *that* was the tech I had been telling people about, but it wasn’t flexible yet… now the LG curved OLED display is out, but still not flexible. Lately when people I know tell me how much they want a new, or just got a new “LED display” I have to explain how it is still really an “LCD” display with an LED back light… But real “OLED” displays that are flexible will be coming out within the next 2-5 years. I guess I just sound like a know-it-all, idiot. They will come… but when? What’s the holdup? I’m guessing it may have to do with just how flexible they can be made without breaking. Perhaps is a simple problem with a complex solution like tiny metal wires that form the electrodes that can’t flex that much without tearing apart or something??

    J

    1. The hold up is the encapsulation. Glass is not as flexible as plastic but plastic is a very bad barrier for oxygen and moisture for which oled materials are highly sensitive.

    2. i don’t understand the craze over oled. i don’t like the tech at all.. it has too short of a lifespan imo. i had an autopage rs-1000 car alarm that had an oled display on it, within 2 years, i could barely make out the display in a dimly lit room..

        1. I’m not aware of any OLED-based smartphones out there. Every smartphone I’ve seen has had an LCD display, with one brand having an e-paper display on the opposite side of the case

  5. The format: a “scroll”. Two kickstand style legs hold the shape when the screen is unrolled, the screen can be hand-wound or spring driven (like a venetian blind).
    Conventional batteries are held in one tube of the scroll, smart electronics in the second tube. Navigation buttons on second tube as well.

  6. I don’t believe they can ship the UI alone in just one year with this many people, and I doubt they can get the hardware for so cheap in such a small volume order (and I’m still talking about a regular custom made phone, not a flexible one). The Neo900 which was a simple replacement PCB for the Nokia N900 was gonna cost twice as much (I’m not sure if they did manage to get the Neo900 to production in the end or not).

  7. I think the biggest problem with OLEDs so far, is the blue light material, that is very reactive when being exposed to Oxigen. That’s why the displays are already working, but normally not for very long, cause the material just oxidizes.

  8. One hitch is that a flexible display unfolded or unrolled typically isn’t that flat. It often remains awkwardly curved or even wrinkled. That introduces distortions that users don’t like particularly in handheld gadgetry and for uses such as reading. No matter how you orient it, parts are reflecting light.

    To work, a flexible display needs to snap into a flat or smoothly curved position. It can’t be just ‘kinda flat.’ And it can’t introduce needless weight and complication in what keeps it in that more usable position.

    Think of the frustrations of a rolled up map that, when you try to use it, keeps wanting to roll itself up. Yeah, you can use weights to hold it open on a table, but remember for these displays we’re talking about gadgets that are supposed to be light and compact. The equivalent of weights and a table defeat that purpose.

    If flexible displays start to have uses, I suspect that it’ll be in contexts where they can are wrapped around a permanent fixed surface like the band of a watch or the displays on a car. The benefit won’t be roll-up, roll-out. It’s be simplicity in installation.

  9. 1. Because the display isn’t the only thing that needs to be flexible.

    2. Because when you have something electronic that is also malleable, the life expectancy and reliability plummets through the ground. Nobody wants to buy a gadget that lasts 3 months.

    So while some may ask “why haven’t we seen bendable gadgets yet?”…. I’m asking “why do people expect this is even possible, and still have it work long enough?”

    1. Hey Hack-a-day, you mentioned in another thread that you are now only providing one hack link each day. Is there any way you can provide us with a way to view just that one hack and none of this stupid bullshit?

  10. TIL: screws are obsolete.

    On another note: according to the article from 2013 they linked, they were planning to release “the One-by-One, an ultra-slim, wireless-charging phone with its own operating system” this January. There is no reference to such a phone anywhere on their site…

  11. I had a look at this, the main problem isn’t the OLED but the control circuitry.
    Its been possible to make a passive matrix display for close to 10 years but as e-ink companies found out to their co$t the backplane does not like being bent repeatedly.

    I did have a thought about making each pixel have its own nanosized CPU and sending the data via infrared, this would get around many of the problems AND animations would then be easy.
    The cost would be slightly higher but 14nm ICs are simple enough and spherical chips have been around for a while (google “Spheral solar cells”)

    A related modification is to integrate the RGB OLED serially so only a single top contact is needed in a similar way to the Sony BRIR diodes, the colours are then produced by shorting one or more of the emitters to its neighbour to dim it down.

    Other advantages of my design are: can be painted onto a surface using the red OLED as the sensor on top for power and microencapsulated in tiny 0.1mm UV cured resin spheres so it would be very nearly indestructible.

    As the chips are identical the brightness should be very uniform and even if the paint is lumpy the workaround is to use a camera to feed back to the system processor.

    1. You can do IC’s with a 14nm process, but you’ll not get a complete IC at that scale. Heck, the package size is going to have to be larger than a standard pixel just for manipulability on anything other than the most expensive lines. I suppose you don’t have to package each nano CPU individually, but printing them in a flexible medium also isn’t presently an option due to the physical limitations of terminal/pin bonding. An iR rx module for each nano CPU isn’t presently feasible either. Even if scale were possible, the sheer number of interconnects on a flexible backplane completely hose the possibility of successful production at present, and certainly the possibility of selling such a thing (if it were possible) would result in per unit costs higher than the budgets of some 3rd world nations. Your only buyer would be a few militaries, and those buyers would want such units for R&D, not deployment. Flexible layers are brutal to pull-off as a prototype, never mind as a product. Between individual layers each wanting to flex individually, the shear forces and distortion, and dissimilar properties between portions of even single layers, we’re going to need several more generations of progress before such a thing can ever jump over the production hurdles.

    1. I think this is more (or also) a ‘trick’ to get some people in the tech industry to take notice and start to do something about getting flexible displays in the circuit. Which then yes the company can do things with too.

  12. Apart from the trouble of making an entire device flexible, I think that due to the various layers required for displays and the smallness of the pixels and connects the failure rate would just be too large to make it a viable enterprise to sell them.

    The real question is why aren’t there more devices with some constrained flexibility, like that TV that can be flat or somewhat curved but then for smaller devices,I think that would prevent issues but still be useful in some designs.

    Maybe it’s the same thing as the question “why does apple have to make something obvious before the others also do it.” and it just needs some sensible person who also has some design talent to get in play before we start seeing it.

  13. Imo, it would be nice to have a larger screen that you could fold into something that fits inside your pocket, a screen which could be folded together twice over without cracking or leaving a mark or dent or fold.

    1. People don’t even want their phones in their pocket anymore. Don’t ask, I don’t know why, but there are millions of people using happily their Galaxy Notes and iPhablet 6es. If there were an iMac with GSM support and a battery, they would find reasons to justify dragging around 15 pounds of metal in the trunk as a “phone”.

  14. Because look inside a phone or tablet, what part can bend? The 10+ layer PCB that is completely covered in chips? The battery? The antennas? The speaker box? How about trying to press a button on a flexible phone? Now look for a nice display that wasn’t made as a phone/tablet part…. They really don’t exist.

        1. I meant that they probably exist as version not designed for tablets and phones there. The japanese for instance have tons of interest in electronics and you have various markets like industrial and medical devices and such, markets where they have displays we are not likely to stumble across in daily life.

  15. I really wonder who’s naive enough to give those indiegogo campaigns their money.
    I also wonder why hackaday is always giving them free advertisements without warning people, that they are most likely cheated out of a bunch of money.

    It’s the same story over and over again. Just include some “free energy” campaign, at least the people contributing to those are already suckers, not just innocently unknowing technophiles.

  16. Its a scam. They dont offer any watch, only discounts or gift certificates if you purchase the watch when available. There is even a tier that offers you extended gifts if you convince other people to join.

  17. “how surprising that no major manufacturer thought of that.”

    While the reliability/plausibility of any single crowd-funding venture should be question, “major manufacturers” typically are very conservative in their ambitions. Content to sale us small variations rather then big changes.

    It was the Pebble that introduced the smart watch to the world at large, not Samsung and certainly not Apple.
    Meanwhile HP has only just started looking at consumer level 3d printers. The techs been there at least a decade if they wanted to touch it, but it was smaller companies proving a market first.

    Very few big companies are willing to have failures – Googles the only one that comes to mind. (specifically with their “10 times better not 10% better” ideology).

      1. https://gigaom.com/2013/09/03/what-microsoft-got-right-with-its-smartwatch-nearly-a-decade-ago-more-than-you-think/

        There have been other smart watches. I think the open question was whether the market was ready for them. Personally, I think the open question is whether the broader market really wants a smart watch. A lot of companies trying to beat each other, but it’s too new of a market to see if consumers in general are buying them in notable numbers. The people I know that have Pebbles and such are the early adopter types.

    1. Actually, the Motorola Moto Activ sports watch came out before the Pebble (i think). It never gets mentioned with “smart watches” yet it’s a full fledged (albeit) low-ish powered, Android smart watch (especially if you root it). sorry. off topic.

    2. Hate to say it, but a few big companies already tried smartwatches before pebble, sony for instance had a miserably failed watch like that. (And I hate sony, hence why I hate to say it :)

  18. There’s so many possible issues, and getting a durable flexible and often-flexed display probably

    Just take a look at how long it took for OLED to take hold, it’s been an “upcoming” technology for very long time, while researchers worked to address its drawbacks that would have prevented consumer acceptance. And we still don’t have large format OLED screens readily available.

  19. I think the problem has been, how do you allow flexibility while also limiting it. If the example phone is real, their solution is the squares on the back of the phone. As the phone flexes, those squares will touch, distribute the flexing and stiffen the phone as it’s flexed. If that is a fake, it’s a well thought out one.

  20. Kodak (I think) had a flexible dot matrix LCD display 15 or more years ago . It was a custom (anything you wanted) and could be wrapped around a 2.0 dia. They used an iron connector, flexible of course, and the cost was under 10.00 in qty. The problem with LCDs is they don’t last very long. The project I was on reqd about 10 pieces and they advised me to buy 100.

    Wrist worn devices present one big problem, the antenna. Since everyone is a bag of water, some bigger, some smaller there is a capacitance problem to solve.

  21. Hmm Interesting, How can you sell the first 0-100 serial numbered units twice? They offer it at the $349 tier which they sold out 100 units of. but they also offer the the first 0-100 serial numbered units again at the $449 tier. Plus, and correct me if I’m wrong here but wouldn’t 0-100 actually be 101 units. It would concern me that a supposed cell phone designer and programmer can’t understand 3rd grade math…… point-to-ponder.

  22. Hmm Interesting, How can you sell the first 0-100 serial numbered units twice? They offer it at the $349 tier which they sold out 100 units of. but they also offer the the first 0-100 serial numbered units again at the $449 tier. Plus, and correct me if I’m wrong here but wouldn’t 0-100 actually be 101 units. It would concern me that a supposed cell phone designer and programmer can’t understand 3rd grade math…… point-to-ponder.

  23. Reminds me of Ginsu knives. Yes, you can cut through a nail, and it will still be sharp enough to slice a tomato with ease. And doing so makes for a great demo. Just don’t expect to do it repeatedly, and have the product last.

    Perhaps then the best use of flexible screens is to put them in applications where they won’t normally be flexed. But would better survive occasional shocks and impacts that might crack a traditional screen.

  24. We do have flexible displays that are flexible enough to roll-up with a small radius, they just don’t work that well:
    http://www.sony.net/SonyInfo/News/Press/201005/10-070E/

    The display here was only tested to 1000 cycles and it appears in the video that contrary to what sony says there is most certainly degradation of the display. 1000 cycles is not much, this is scrolling and un-scrolling the display twice a day for about a year. Ideally, these things should last around 8000 cycles, because that translates to about 2 years of heavy use, which should be about the length of a typical cell contract.

    Making displays that are flexible enough to roll up is hard to do because you need to make everything in it capable of strecthing by a factor of a lot. Pretty much everything that is conductive enough for electronics can’t be stretched all that much. Copper and aluminum also have really bad fatigue properties. Whereas if you build something out of steel the right way, you can stretch it and unstretch it repeatedly practically forever. With copper and aluminum, no matter how you build it, any oscillating stress at all, will eventualy cause them to fail.

    Now making displays that fold would be even harder, in order to get a sheet of material to fold, you have to stretch far enough that it won’t stretch back(plastically deform it). For electronics doing so is really bad, if you plastically deform an electric circuit, you may have unintentionally put some new resistors in your circuit. Some of which might have absurdly high resistance values.

    Now there are some really clever ways around this, like using circuits made of liquid metal, but they aren’t really ready to be mass produced:
    http://rogers.matse.illinois.edu/

  25. Conspiracy theory explanation : The government is using these in large scale form to cloak planes and tanks and other vehicles. By allowing the technology to further advance in the private sector would allow other countries to do so as well. I’m not being sarcastic, I really have this weird feeling that it might be happening. Maybe.

    1. the problem with this idea is that would make horrible camo. that kind of active camo only works for one pov while for any one even a little outside of that angle would see this obvious image flouting in space.

  26. It doesn’t matter if it has new technology. They are claiming they can build 100 of a modern cell phone for $350 each. Custom PCB, custom case. There is no way they can get anywhere close to that on any element of the build on its own.

    Add to that they are claiming to make 100 new custom displays for significantly less than $350 a piece.

    Oh, and its going to be significantly thinner than all the other smartphones on the market (4.8mm). And waterproof, and have 4 cameras. No bezels.

  27. Re. ideas.
    I have a website, see http://www.cwgsy.net/private/mandoline
    Also working on superconductors, have actually made samples of a possible candidate for a room temp. (281K or 7.8C) material based on lead doped pyrographite.
    Seeing 15% resistance drop when immersed in a solvent and it slowly recovers when out (presumably the drying pores force the lead back out) so a composite material with the right ratio of lead or other heavy metal to carbon ie 1:700 would probably work.
    This was six months ago and it just occured to me this week what was going on, as thought it was measurement error.

  28. Small runs of flexible OLEDs are actually closer to $50 than $350 as they are handy for calibrating the system for larger displays.
    Think about it, would you rather waste $1000 worth of OLED to find the display is misaligned and useless or $20 for the ink and $30 for the substrate?
    Same reason why they make test wafers using the masks with alignment points and ye olde 8088’s at the edges: if those fail after the first few steps they scrap the whole wafer rather than wasting MOCVD time on it.

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