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Using a laser to wirelessly charge a smartphone safely across a room
- Yaggo 9y agoNice demo but way too complex and limited (requires line-of-sight) for practical use. I would rather take a MagSafe-style zero-force dock.
- svantana 9y agoI can't believe true effortless phone charging still isn't solved. The capacity of a phone battery is about 8 Wh, which would mean that an "ambient" charging solution in a bedroom would need to provide 1W of charging to be feasible. We already know that we can put decent antennas for microwaves inside phones at low cost (e.g. WiFi), so what's needed is some form of tracking beamforming from the transmitter to get reasonable efficiency. Even if only 10% efficiency can be achieved, that should be a viable product (leaving aside the moral/environmental aspect of energy waste). I guess part of the reason why it doesn't exist is non-technical hurdles, FCC and radiation fears.
- isfield 9y agoI see what you're saying. We all want to improve technology here right. But I don't find it a great deal of effort to leave my phone on a charging mat when I go bed already. I think we're already at an efficient cost of effort over financial cost of an even more effortless technology already.
- rickycook 9y agofor me, it’s not about when i go to bed. that part’s easy already; it’s about when you’re at a friends house, or work, etc for longer than you expect and your battery starts to go flat. in this case, you think “i should have just charged my phone; i was next to a USB port all day”. it totally eliminates these situations once lightbulbs with charging become common place because you just show up and your phone starts charging without thinking about it
- mseebach 9y agoIt's very likely that the low-tech alternative just catches up way sooner than the (objectively better) high tech solution becomes viable. The low tech in this case is that your friend probably has a compatible charger, and it's probably even already lying around so you can just plug in without even breaking conversation. (There are a number of incompatible standards out there, but wireless charging would also be beset by competing standards)
- mnx 9y agoReally there are only three standards I can think of - micro usb, covering probably 80%+ of devices, whatever the current becoming popular. That's way better than it used to be.
- stordoff 9y agoI suspect ubiquitous charge pads will get us most of the way there a long time before any sort of long distance wireless (especially if e.g. the EU mandate a single charging standard as they did with micro USB). If they are everywhere, it's relatively easy to remember to put your device there, and forgetting to do so doesn't matter most of the time if/when you can get a meaningful amount of charge in just a few minutes.
- svantana 9y agoFirst off, I'm not saying I want this tech, I'm saying it would do well in the marketplace if it existed. Second, the 'effort' is not the physical act of plugging in, but rather the mental act of remembering to. Plus the potentially huge downside of running out of battery in a precarious situation.
- willvarfar 9y agoThere are lightbulbs that form mesh networks using lasers. I forget the name but I recall it being on HN last year so it must be true! A quick googling finds something similar https://techcrunch.com/2015/09/14/linux-light-bulbs-allow-devices-to-talk-to-each-other-with-flashes-of-brilliance/ https://techcrunch.com/2015/09/14/linux-light-bulbs-allow-de... If lightbulbs can provide wireless power to devices in the room that would be awesome and have practical applications even if it can't charge something as power-hungry as a phone very quickly.
- varjag 9y agoThey don't use lasers.
- sandworm101 9y agoLightbulbs already do this: solar panels work perfectly well under bulbs of many type.
- Yaggo 9y agoTypical 5 watt solar panel is 25x25 cm. That 5 watt is generated under ideal conditions, i.e. in sunlight, measuring about 100 kilolux. Bright indoor lightning is 1 kilolux, i.e. the "indoor solar panel charger" would take ~6 m² (assuming ideal spectrum).
- taneq 9y agoEven just wireless contact charging. Battery life isn't a real issue on phones these days, as long as you plug it in when it's not in use.
- nathan_long 9y agoDefinitely. Especially since in either case, you have to put the device in a predetermined place. > the emitter could be aimed at a wider charging surface, such as a counter or tabletop, and charge a smartphone placed anywhere on that surface. And because in order to notice that the device is there, they have to also make it emit chirps > The researchers programmed the smartphone to signal its location by emitting high-frequency acoustic "chirps." These are inaudible to our ears, but sensitive enough for small microphones on the laser emitter to pick up. End result: a phone that chirps all the time (you can't hear it, but maybe your dog is annoyed or your security system is triggered), in order to let the charging system notice that it's sitting in a predetermined location, so that it can fire a laser at it, which needs safeguards to keep from hurting you. Also this method is apparently inefficient, given that they need a heatsink for the laser. How about no chirping, no lasers, and we just make plugs that are easy to use? (The old round barrel-style plug on my ancient flip phone was easy to plug in, even in the dark.)
- deleted 9y ago[deleted]
- jeena 9y agoI'm using a Qi charger instead which I put on the table. Ikea has them build in to tables, night stands, lamps http://www.ikea.com/us/en/catalog/categories/departments/wireless_charging/ http://www.ikea.com/us/en/catalog/categories/departments/wir... they are really safe because there is no laser involved.
- Baeocystin 9y agoI use Qi chargers as well, and they do work, but man... They would be so much better if they had even a few more millimeters of leeway in their positioning. As it is, each Qi device I have needs to be just so or it won't work. The fast wireless charger I got for my S8 is better than most, but still picky. I genuinely do think this needing to pay close attention to positioning is their biggest limitation to wider adoption. (that, and android's insistence on turning on the screen to announce full charge, turning off, then turning back on again...)
- bayindirh 9y agoI use Belkin's charging mat for iPhone X, and it's not picky about the location. Just putting it approximately centered is enough to start charging.
- stordoff 9y agoI purchased one recently, and ended up sending it back the second time I woke up and found the phone to have <10% charge. I found because my phone is right next to my bed, the slightest nudge of the table it was on was often enough to misalign the phone (and it would usually start an endless cycle of charger recognised -> screen turns on because the phone thinks it's charging -> charging doesn't work -> connection broken, draining the battery in the process). Definitely convenient, but also really finicky.
- rsynnott 9y agoApple's forthcoming qi charger mat is supposed to be less finicky than most, though it'll be quite expensive. Being super-fussy about positioning doesn't seem to be intrinsic to the technology, though.
- sschueller 9y agoWhat was/is the name of the company claiming they can do that but have not produced any documentation proving it? Yet they have been collecting a substantial amount of investment.
- TeMPOraL 9y agoYou mean the possibly longest running joke of Silicon Valley? That's uBeam, but they're the ultrasound people.
- avian 9y agoI would never be comfortable having an exposed, multi-watt laser in my living room. One failure of the (most likely software) safety device and it will burn a new blind spot on your retina in a fraction of a second. Having had a brief working experience in a lab involving high-powered lasers, I have an unreasonable fear of these things. A random beam reflection can hurt your eyes in a painless way. You only notice the damage later when things start disappearing from your field of view (similarly to how you're not normally aware of your natural blind spot). I've been told that everyone that retires from that field of research has had holes burned into their retinas despite strict safety procedures.
- userbinator 9y agoThe article makes brief mention of this... the emitter detects this within a fraction of a second and deploys a shutter to block the charging beam before the person can come in contact with it A mechanical shutter also seems strange --- cutting power to the laser would probably be faster by at least an order of magnitude if not more, if it's a solid-state type. As the memorable sign says, "Warning: Do not look into beam with remaining eye."
- TheOtherHobbes 9y agoThis project screams lack of imagination and downright incompetence. You need case-by-case legal paperwork to do high power (i.e. more than a few tens of mW) laser shows in the US if there's any chance of the beams scanning the audience. The idea that you can set up a 2W laser in your living room and make it 100% safe by adding mechanical movement detection is outstandingly stupid and ill-advised.
- throwaway413 9y agoOssia demoed this type of tech at CES this year. I believe they have a very solid offering. Source - my colleague works there. https://www.ossia.com https://www.ossia.com
- borgchick 9y agohttps not working for me, http did though
- throwaway413 9y agoWoops, thanks - typed it by hand and made the assumption. Going to tell my buddy to have that fixed!
- walrus01 9y agothis is a cool thing to build in the lab but I think will have just about zero real world practical uses. interestingly enough there exists a small, but real market for power over fiber. usually used for things like electronic sensors embedded inside the fuel tanks of $50m+ aircraft. or in certain very sensitive parts of an oil/gas refinery. basically a laser, a fat plastic fiber optic cable (way bigger than 62.5/125) not very dissimilar from TOSLINK type stuff, and a triple-junction GaAs concentrator-focused photovolatic cell, with the cell wired to a dc-dc converter. https://www.fiberopticlink.com/products-item/power-over-fiber-system-pof/ https://www.fiberopticlink.com/products-item/power-over-fibe...
- xchaotic 9y agoDo not look into the laser with the remaining eye
- jlebrech 9y agoWe could do this with cars: Laserroadways
- didip 9y agoCan’t the laser be contained inside fiber optic cables? If so, then it’s much safer than direct beam. This also means fiber can now deliver power.
- Retric 9y agoThe problem with power over fiber is not the fiber, it's the sensors you put on the other end of the fiber.