Immediate to near future, we are talking about single digit nanometer size transistor and light emitting diode. That's actually very small, you can't see it with a conventional microscope let alone magnifying glass. I need a pair of contact lenses that could allow me to browse the internet for at least 2 hours when exposed to a healthy wifi signal, the electronic components such as display, antenna, processor with embedded graphic, random access memory for storing working data etc will be fitted inside a gas permeable flexible polymer. I'm missing a power source to supply ultra low wattage current to drive the comfortable super energy-efficient internet enabled contact lenses, what available technology today can I use for my lenses?

Criteria/minimum specs:

  1. Compact and lightweight.

  2. It must not melt or explode under any normal circumstances.

  3. Must not obscure vision.

  4. Must be rechargeable.

  5. Built-in/ bonus points for exchangeable or support wireless charging!

Note: disregard energy consumption and handwave the antenna only.

  • 2
    $\begingroup$ What's wrong with using a tiny battery? $\endgroup$
    – Aify
    Jan 27 '17 at 6:52
  • $\begingroup$ @Aify: opacity and heating... $\endgroup$
    – user6760
    Jan 27 '17 at 7:05
  • 1
    $\begingroup$ you could use the lenses for only displaying; the computer can be outside of the lenses. Then you can use bluetooth or communication via electricity transported via the water on the skin, and the computer can connect to wifi or LTE or something else (even ordinary LAN). So your lenses do not need the power for wifi but only for the display $\endgroup$ Jan 27 '17 at 8:11
  • 4
    $\begingroup$ If you have advanced electronics in nano scale, then you shouldn't really limit yourself to modern tech power supply. Sure, we already now have developed single molecule oled, but it's not available in any actual tech. By the time we have the capability to shove a complete cellphone into a contact lens, then we will likely have better ways to power it too. I suggest induction from the neurons in the eye/face of the wearer, pyroelectricity, or a tiny battery hooked to some micro solar cells on the outside of the lens. $\endgroup$
    – Mrkvička
    Jan 27 '17 at 12:00
  • $\begingroup$ Because the eye cannot focus on the cornea, your "display" would need to aim highly collimated laser-like beams in different directions to strike different parts of the retina to form its images. It would be a holographic output very different from anything we've used so far, and comparable devices not placed in the eye would look quite remarkable. But the propensity of such displays to have all their elements abruptly focused in the same direction might make them quite hazardous when hacked. $\endgroup$ Nov 25 at 12:47

As Steve notes, the great Vernor Vinge postulates such contact lenses in the universe imagined in Hugo-winning novella Fast Times at Fairmont High and the Hugo-winning novel Rainbows End.

He describes smart contact lenses being powered by the thermal gradient between body/eye temperature and ambient air temperature. The lenses offer full augmented VR and have the added bonus of being instant protective shields from high-intensity light such as military laser weapons discharge. Vinge describes the unpowered contact lens as being foggy-white when not placed on the eye; and turns clear moments after being placed on the eye.

Miri didn't seem to notice the look. She leaned her head forward, and stuck a finger close to her right eye. "You already know about contacts, right? Wanna see one?" Her hand came away from her eye. A tiny disk sat on the tip of her middle finger. It was the size and shape of the contact lenses he had known. He hadn't expected anything more, but... he bent close and looked. After a moment, he realized that it was not quite a clear lens. Speckles of colored brightness swirled and gathered in it. "I'm driving it at safety max, or you wouldn't see the lights." The tiny lens became hazy, then frosty white. "Uk. It powered down. But you get the idea." She popped it back into her eye, and grinned at him. Now her right eye was fogged with an enormous cataract.

"You should get a fresh one, dear," said Alice.

"Oh no," said Miri. "Once it warms up, it'll be good for the rest of the day." And in fact the "cataract" was fading, Miri's dark brown iris showing through. "So what do you think, Robert?"

  • $\begingroup$ it sounds smart, with a little caveat: for various reasons (improve contrasts, focus only on the lens content, you name it) one may want to use the device with closed eye-lids. But then the temperature gradient would be gone or at least stongly reduced. $\endgroup$
    – L.Dutch
    Jan 27 '17 at 8:27
  • 1
    $\begingroup$ I'm pretty sure by "augmented VR" you mean augmented reality, or AR. I haven't read the story, but it sounds more like an overlay over vision than a full virtual reality. $\endgroup$
    – Nic
    Jan 27 '17 at 13:41
  • $\begingroup$ @qpaystaxes Vinge defined the terms for his story, before the categories were so well defined in real-life; he foresaw a continuum of virtual and real interplay without strong delineation. Visionaries of the future get a pass on such things. When you win the Hugo, you can redefine the terms, too. ;-) $\endgroup$
    – SRM
    Jan 27 '17 at 14:19
  • 1
    $\begingroup$ I am Steve, and I endorse this answer. BTW, how does one find complete quotes from the book? I would have of had to go to the library to check the book out and manually type in the section that JD provides here. $\endgroup$
    – Steve
    Jan 27 '17 at 18:06
  • 2
    $\begingroup$ @QPaysTaxes In the later novel, he has VR overlay on reality with haptic technology as well. So it’s not augmented reality but a full-body unobtrusive implementation of VR, which still has to cope with the physical reality of the space. You really should read it! $\endgroup$
    – JDługosz
    Jan 27 '17 at 22:01

We blink all the time. Maybe the motion of the eyelid over the contact could power it, either by magnetic induction planted in the eyelid (kind of like how those wireless charging pads work on phones or by parasite robbing some of the kinetic energy of the eye closing and opening and converting it to physical energy. Could pair this with solar recharging (if the system is designed to work with the eyes OPEN, not closed) to extend battery life.

You can also have a small battery slipped over behind the eye. I once participated in a research project that required me to have a thin silicone tube slid behind my eye (to see how well it would be tolerated for medications). Lived with it for a month and it wasn't very noticeable. Could easily have this be a battery pack that feeds power to the contact. Of course putting the contact in and taking it out would be more laborious, but hey, that's progress!


Since you rely on wi-fi communication, you can use RFID-like technology to power your circuits.

  • The wi-fi can supply energy and data to your wearable device
  • a tribologic generator powered by the bearer body can wireless power the device (you can use breathing movements, as they are constantly done)
  • a small phovoltaic panel can do the same (only during day).

You might want to extend the area of the lens, using the display part on the pupil area, while using the rest as energy absorber, so that you avoid concetrating too much energy flow (you don't want to cook the eye, right?)


You can power them through the use of a resonant coil to wirelessly transmit electricity produced by an external system. For better features, the coil can be made of a very thin tube of ionic solution, using a cooling container in the very middle of the lens to mitigate the heating effect.

Using a stable neutral pH solution will make it safe in case of leaking in the eye.

Since resonant magnetism is safe, transmission of the current could be done worldwide.

A small gel battery can be used to make the power sustain on main power loss.


Not the answer you're looking for? Browse other questions tagged or ask your own question.