Skip to comments.Want to see at night? Here comes the infrared CONTACT LENS
Posted on 04/02/2014 3:26:37 AM PDT by markomalley
University of Michigan boffins have created a tiny light detector that reaches into the infared, and is already small enough to be delivered as a contact lens.
The key trick, the researchers say, is that they've created an infrared detector that doesn't need the cooling demanded by most devices that currently operate at the mid-to-far infrared wavelengths.
As UoM assistant professor of electrical and computer engineerings Zhaohui Zhong says, the design can be built so thin that It can be stacked on a contact lens or integrated with a cell phone.
The university's release explains that while the near infrared (that is, wavelengths closest to visible light) isn't too hard to deal with, medium- and far-infrared sensors typically need to be at low temperatures.
Their work, published in Nature Nanotechnology (abstract), started with graphene because it is sensitive to a broad range of wavelengths (including the infrared).
However, graphene is quite insensitive as a photodetector, yielding tens of milliamps per watt because it's only offering a single layer of carbon atoms to the incoming light. That, Zhong said, is a hundred to a thousand times lower than what a commercial device would require.
To overcome this, the researchers integrated an amplifier into design based on two layers of graphene separated by a thin insulating layer, and ran a current through the bottom layer. When light hit the top layer, electrons were released to pass through the barrier, and the positively-charged holes left behind in the top layer altered the flow of electricity through the bottom layer.
The variation in the current in the bottom layer, rather than the electrons released, is what indicates the light hitting the detector, and the researchers claim that they achieved mid-infrared responsivity higher than 1A per Watt, making the device comparable with commercial detectors. ®
Matter of time before we have Geordi style contact lenses. Control it with your cell phone and click through the spectrum.
Doesn’t say if it is a starlight device or if an infrared source light is needed
Sounds like a wonderful thing to have for long walks in the woods at night; anybody know if this will be as good as/better than a next-generation Night Vision Device (NVD)?
That’s what’s confusing. Is it detecting photon emission or thermal radiation variance?
Current hand held mid wave imagers cost between 50k to 100k. If it can see into mid wave IR, it’s a real technology leap.
The sensor may be contact sized, but not the power supply.
It’s all fun and games until someone turns the lights on.
so, would have to be a “lens cap” on the front of a rifle scope...
Since you’ve already got a battery in there.....
(and I’m too cheap to buy the $2K-20K versions)
"Seventh line down; F, E, L, O, P, Z, D".
Why as contact lenses? Why not just as simple, thin, light glasses, rather than the binoculars-sized sets we have today?
Thanks for enhancing my knowledge! I have no formal physics education, just what I’ve gleaned on my own. If you don’t mind, a couple of questions:
So even long wave IR (e.g. 14um) emits photons? If so, do all em wavelengths emit photons?
I realize that bolometers measure temp differences but I haven’t seen one that covers shortwave IR (1 - 3 um) (at least that I’m aware of). Are you aware of any? FLIR makes a SW IR detector (InGaAs) that is limited to 1.7um (and relies on photons). Seems like breaking that barrier (1.7 to 3.0um) is a challenge (or maybe cost prohibitive). That’s ultimately why I find this article interesting. It would be quite a breakthrough if they’ve developed a capability for “see” shortwave IR sans utilizing photon emission. Especially in such a small platform.
Any further illumination (pardon the pun) on your part is much appreciated.
Thanks in advance!
All IR is photons. So is microwave, radio wave, etc. And at the energetic end, x-rays are photons too.
The application they refer to is just one of many that this will be able to be used for based on their description. This could completely change the way that all photo to data electronic transmissions are made across all spectrums and could greatly reduce size/cost of multiple optical, radiation, and/or electromagnetic detection devices. An immediate application I see would be in astrophysics to either 1) increase the sensitivity (thereby obtaining greater data for same size) or 2) reduce the size of the receiver for telescopes (both optical and radio)opening up additional remote siting options.
Thank you very much!
I'm thinking more like this than a visor:
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