That's a very creative way of spicing up a boring old glass eye! I imagine such "wearable" tech could also be the ultimate version of those snapchat glasses.
Putting a battery inside your eye socket seems incredibly risky to me, though. Especially one that can power a bright light like this for a while...
I wonder what power laserpointer you could fit in there without going overboard with the battery... Imagine being able to light matches by looking at them for a bit.
On the other hand, every mirror would be a great chance to lose your other eye as well, so maybe disregard my ideas.
A low-power laser pointer would still be very interesting and perfectly safe. Star Trek/X-men/Superman/Star Wars dreams of stunning enemies with a beam of light from your eyes, there's no to have power levels that can light matches, pop balloons, or otherwise cause destruction.
One cool use, IMO, would be a time of flight distance-measuring laser: With only a single working eye, OP lacks binocular vision for distance measuring. With the equivalent to a Bushnell rangefinder, they could stare at an object, blink twice, and hear a tiny voice literally in their head say "37.84 meters".
Might not even need a voice. I wonder if you could “tap into” the remaining bits of the optic nerve and send a signal that way. The signal would vary based on distance. Maybe simulate intensity of light or something.
Would probably require some kind of crazy training for it to work. Plus I have no clue what I’m talking about!
> On the other hand, every mirror would be a great chance to lose your other eye as well, so maybe disregard my ideas.
At those power levels? Probably every surface in general. A beam powerful enough to light a match or burn through a balloon is powerful enough for the diffuse reflection off a table or wall to blind you.
If you're eyelids are closed, you can't be looking at what your aiming. Your chances of hitting the target increase infinitely if you keep your eyes open.
To provide more power to the led you probably need a bigger coil inside the eye, it should work if you hide the induction transmission loop inside a hat.
Honestly while a lithium battery might worry me I’d be more worried about heat dissapation. Of course the dude says it isn’t an issue, but still.
I guess it might not matter much because the battery is so small that you’d be lucky to get more than a handful of minutes running that LED at max power.
This is all speculation based on a 30 second video though.
The one in your pocket is dry, plus if it did somehow start conducting through you it'd zap your leg/wrist and hurt, maybe cause you to spasm and kick something, but that's it. If one on your heart/in your eye socket does it, it wouldn't take much for that to give you a heart attack or shock your optical nerves which is a very short wire into your brain, and as such I can only imagine it would be very very bad for you.
Pacemakers and implanted defibrillators are both, uh, implanted inside your body. Typically they stick them in the front side of your left shoulder. They run the leads into a vein (or artery) and anchor them into the wall of the heart.
They can implant basically under the fat layer or under the pectoral muscle. Beneath the fat layer is easier both from a surgery and recovery standpoint, but less secure.
The downside of that is that it's possible for the device to flip over. They usually try to avoid securing the device to anything because that can lead to discomfort or pain if the device wants to move around, but they can if they have to.
And yes, they do have to repeat surgery to replace the device when the battery gets low. The leads AIUI are usually a lifetime part (hopefully for all the right reasons). For defibrillators, battery life will be maximized if the device doesn't have to deliver shocks and can stick to just pacing. It turns out if they implant a defibrillator, you get a pacemaker for free.
But that's not true... A pacemaker goes inside your body. It's replaced during a surgery every 15-20 years and has enough battery lifetime to last that long.
There used to be nuclear-powered pacemakers that could last many lifetimes but nowadays the doctors say it's better to replace the whole thing every once in a while, so the nuclear option is overkill.
> Despite the often longer life-expectancies, nuclear pacemakers quickly became a part of the past when lithium batteries were developed. Not only did the technology improve, allowing for lighter, smaller, and programmable pacemakers, but doctors began to realize that this excessive longevity of nuclear pacemakers was excessive.
Good points. But a low-duty-cycle laser pointer eyeball could be more useful than a low-duty-cycle pacemaker.
You could use the 2μW to charge up a capacitor for 24 hours and then have a minute and a half of 2mW, which is enough for a visible laser pointer reaching a few meters. 2mW light output is quite a bit brighter than that but requires more like 20mW power input.
A 220 μF cap at 48 volts would hold 35 hours of 2μW, and there are ceramic caps that big that would easily fit into your eyeball.
The lightest weights 2.6 g, which is 1/2 the weight of the eyeball, so cuts the power generation to 1μW.
I think it's telling me there's a 10μA leakage current, which I think means the cap will power up to 0.1V before the leakage rate matches the power rate.
Now that you know my level of ignorance, what's your take?
Yeah, that's a wet tantalum cap, those have higher leakage currents. An X7R MLCC like https://www.digikey.com/en/products/detail/united-chemi-con/... will probably have lower leakage, though the datasheet doesn't specify. Digi-Key says it costs US$45, it's 20 mm × 28.5 mm × 10 mm which is 5.7 cc, and probably close to 15 grams.
Leakage current usually increases superlinearly with voltage, though. If the tantalum's DC leakage is 10 μA at 50 volts, it's probably closer to 0.1 μA at 5 volts.
In capacitors with a given dielectric, the maximum energy is proportional to the volume of the dielectric, so although a 47 μF cap charged to 108 volts stores the same energy as a 220 μF cap charged to 50 volts, it also needs the same volume.
(I'm not an EE either; I only play one on HN.)
https://en.wikipedia.org/wiki/Human_eye says an adult human eyeball is about 23.7 mm × 24.2 mm × 23.4 mm, and a spheroid like that is π/6 of the corresponding cuboid, so you only have about 7.03 cc to work with.
So probably you'd have to settle for under 1 cc of capacitor, which (in the case of X7R anyway) means storing more like 15 seconds of 2 mW.
But then this one could be lithium iodide too. A replacement eye can also be replaced more easily.
Anyway, your statement about the pacemaker sitting outside the body with probes going inside is not correct; maybe it once was, but that was decades ago.
Putting a battery inside your eye socket seems incredibly risky to me, though. Especially one that can power a bright light like this for a while...