Inking the Deal on Low Power
Why low power is on display in markets including transportation, medical, wearables and digital signage.
Sometimes applications find themselves at the intersection of Has Information and Lacks Power. That intersection is a sweet spot for E Ink, whose electronic ink display technology only consumes energy when the particles are moving (familiar for its use in Amazon Kindle devices).
In addition to its feature of ultra low power on the order of 5 micro-watts per cm2, E Ink also stands out from LCD and LED displays, because the ink pigments it uses, similar to those used in print, allow displays to be reflective. “Our displays reflect the ambient light in the room in the same way as a printed page,” notes E Ink’s Head of Global Marketing, Giovanni Mancini. He adds, “During the day, we require a lot less power because we don’t require a very strong light to overcome bright sunlight.”
With so many different markets clamoring to do more with less power, there is no shortage of diversity in the company’s customer and potential customer base—everything from the wearable Withings Go activity tracker introduced at the most recent CES to retail shelf tags to body-mount applications. In a recent interview Mancini spoke with me about a number of applications where E Ink solutions are at work.
EECatalog: You mentioned that the display can be plastic, which helps with weight. Is the E Ink display technology one which mil-aero applications, with their need to address size, weight and power challenges, would find helpful?
Giovanni Mancini, E Ink: [Typically] the requirements in mil-aero are beyond the temperature range that we would normally operate on. [However] we have been engaging with some mil-aero customers that are looking for body-mounted applications. For such applications a display providing information that won’t shatter—because it’s plastic, not glass—and which is readable under all conditions, is of interest.
EECatalog: An article we published recently contributed by E Ink’s partner Global Display Solutions pointed out some of the benefits of E Ink/e-paper for transportation. It said this solution could make it unnecessary to run power lines out to remote locations.
Mancini, E Ink: Yes. There are places such as remote bus stops, where deploying digital signage would mean digging trenches and bringing power out there. Contrast that with the trials that we are running in London and the U.S. with bus stops, where it’s possible to simply attach the bus stop to the ground. And you are done. The bus stop connects with WiFi or some other radio frequency Communication protocol, and, because of our low power consumption, the bus stop is powered exclusively with solar cells that charge a rechargeable battery that sits on top of the bus stop.
And in Sydney, Australia with the Roads and Maritime Service (RMS) we have run trials, and they are now deploying display technology using E Ink in traffic signs that tell you when you can park in certain areas and when you can’t park there. Some of the traffic regulations in certain areas are becoming so complex that it’s becoming impossible for drivers to figure out when they can park there and when they can’t. What RMS is looking to do is replace the parking signs with a very simple E Ink based sign that says, “Yes, you can park here” or “No, you can’t park here.” The sign is totally powered by solar cells that sit in the back of it.
EECatalog: Can you describe healthcare areas where E Ink display technology has applicability?
Mancini, E Ink: We’re working with the Palladio Group in Italy to provide smart packaging targeting pharmaceutical applications for healthcare. With them, we have developed a display, about 1.4 inches on the diagonal. Attached to this display is an ARM Cortex-M0 embedded processor, a temperature sensor, some sort of activity sensor, and a very thin, very small battery—that gets laminated into the thin posterboard that the package comes in.
PhutureMed, the prototype product, is simple. It consists of a box with a display on it. The sensor is connected to buttons, so every time you take your medication, you press on the button, and now you have a record of when you took your medication. The temperature sensor can keep track of the medication’s ambient temperature and indicate exposure to temperatures outside the range they are supposed to be in—something very critical for vaccines that become non-viable if exposed to the wrong temperature range.
For some individuals answering the questions, “When did I take my medication and when do I need to take my medication again?” is very difficult. This very simple solution addresses that problem. Also, that same module can be integrated into a tri-fold blister pack, and now, what you have is a much more complete solution made possible by a very small embedded system. This is because in the tri-fold you now have two RFID signatures.
One of the two RFID signatures identifies the medication, so the embedded system knows when you are supposed to take that medication, and it has all the information about it. The second RFID signature is on the part of the blister pack that has the pill compartments. Every time you pop the pill the RFID signature can identify exactly which pill you popped, so now the system knows which pill and when you took it, and it keeps a log of that.
Statistics show that even for very critical medications there is as much as 30 percent noncompliance or nonadherence to the required regimen, and studies have also shown that simply providing the patient with reminders, essentially alarms to indicate “you were supposed to take your medication, you haven’t” improves compliance. And just that level of “nudginess” increases adherence to the regimen. It’s possible because our embedded module uses very little power, so a very simple, flexible battery can be laminated to the cardboard, and it can last more than a year.