Infrared Contact Lenses Allow People To See In the Dark, Even With Eyes Closed (phys.org) 42
An anonymous reader quotes a report from Phys.Org: Neuroscientists and materials scientists have created contact lenses that enable infrared vision in both humans and mice by converting infrared light into visible light. Unlike infrared night vision goggles, the contact lenses, described in the journal Cell, do not require a power source -- and they enable the wearer to perceive multiple infrared wavelengths. Because they're transparent, users can see both infrared and visible light simultaneously, though infrared vision was enhanced when participants had their eyes closed. [...] The contact lens technology uses nanoparticles that absorb infrared light and convert it into wavelengths that are visible to mammalian eyes (e.g., electromagnetic radiation in the 400-700 nm range). The nanoparticles specifically enable the detection of "near-infrared light," which is infrared light in the 800-1600 nm range, just beyond what humans can already see.
The team previously showed that these nanoparticles enable infrared vision in mice when injected into the retina, but they wanted to design a less invasive option. To create the contact lenses, the team combined the nanoparticles with flexible, nontoxic polymers that are used in standard soft contact lenses. After showing that the contact lenses were nontoxic, they tested their function in both humans and mice. They found that contact lens-wearing mice displayed behaviors suggesting that they could see infrared wavelengths. For example, when the mice were given the choice of a dark box and an infrared-illuminated box, contact-wearing mice chose the dark box whereas contact-less mice showed no preference. The mice also showed physiological signals of infrared vision: the pupils of contact-wearing mice constricted in the presence of infrared light, and brain imaging revealed that infrared light caused their visual processing centers to light up. In humans, the infrared contact lenses enabled participants to accurately detect flashing morse code-like signals and to perceive the direction of incoming infrared light.
An additional tweak to the contact lenses allows users to differentiate between different spectra of infrared light by engineering the nanoparticles to color-code different infrared wavelengths. For example, infrared wavelengths of 980 nm were converted to blue light, wavelengths of 808 nm were converted to green light, and wavelengths of 1,532 nm were converted to red light. In addition to enabling wearers to perceive more detail within the infrared spectrum, these color-coding nanoparticles could be modified to help color-blind people see wavelengths that they would otherwise be unable to detect. [...] Because the contact lenses have limited ability to capture fine details (due to their close proximity to the retina, which causes the converted light particles to scatter), the team also developed a wearable glass system using the same nanoparticle technology, which enabled participants to perceive higher-resolution infrared information. Currently, the contact lenses are only able to detect infrared radiation projected from an LED light source, but the researchers are working to increase the nanoparticles' sensitivity so that they can detect lower levels of infrared light.
The team previously showed that these nanoparticles enable infrared vision in mice when injected into the retina, but they wanted to design a less invasive option. To create the contact lenses, the team combined the nanoparticles with flexible, nontoxic polymers that are used in standard soft contact lenses. After showing that the contact lenses were nontoxic, they tested their function in both humans and mice. They found that contact lens-wearing mice displayed behaviors suggesting that they could see infrared wavelengths. For example, when the mice were given the choice of a dark box and an infrared-illuminated box, contact-wearing mice chose the dark box whereas contact-less mice showed no preference. The mice also showed physiological signals of infrared vision: the pupils of contact-wearing mice constricted in the presence of infrared light, and brain imaging revealed that infrared light caused their visual processing centers to light up. In humans, the infrared contact lenses enabled participants to accurately detect flashing morse code-like signals and to perceive the direction of incoming infrared light.
An additional tweak to the contact lenses allows users to differentiate between different spectra of infrared light by engineering the nanoparticles to color-code different infrared wavelengths. For example, infrared wavelengths of 980 nm were converted to blue light, wavelengths of 808 nm were converted to green light, and wavelengths of 1,532 nm were converted to red light. In addition to enabling wearers to perceive more detail within the infrared spectrum, these color-coding nanoparticles could be modified to help color-blind people see wavelengths that they would otherwise be unable to detect. [...] Because the contact lenses have limited ability to capture fine details (due to their close proximity to the retina, which causes the converted light particles to scatter), the team also developed a wearable glass system using the same nanoparticle technology, which enabled participants to perceive higher-resolution infrared information. Currently, the contact lenses are only able to detect infrared radiation projected from an LED light source, but the researchers are working to increase the nanoparticles' sensitivity so that they can detect lower levels of infrared light.
Actually cool news (Score:1)
I want a pair
Re:Actually cool news (Score:5, Informative)
Not quite. IR only shows temperature differences. As soon as you have more than a single layer of clothes on, the temperature differences start to blend together. Almost all titillating IR photos are of women wearing very thin blouses and no bras, knowing they were being filmed with an IR camera. In real life all you would see is warm spots around the face and general heat zones. Besides, these contacts only show general direction of strong IR sources, similar to what you can already do by closing your eyes and feeling which direction the sun is shining.
IR photo comparison [wikimedia.org]
Re: (Score:3, Interesting)
Not quite. IR only shows temperature differences. As soon as you have more than a single layer of clothes on, the temperature differences start to blend together.
I was a USAF tech in my younger years and the IR targeting pods on the F-15E had no trouble looking right through BDU's (cammo) and locking on to the heat generated by a female's breasts (they show up warmer than the rest of the body). It certainly wasn't PornHub quality, but you knew what you were looking at.
Re: (Score:2)
Never under-estimate the ability of a horny teen's visual cortex to fill in any necessary details.
See also 14 year olds watching scrambled cable channels hoping for a brief glimpse of a boob.
Extra advantage for MAGAs (Score:2, Funny)
Re: (Score:2)
Finally a reason to stuff my pockets full of hotdogs...
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If your body is emitting at 1200 nm you might want to take something for that fever.
Prior Art (Score:3, Funny)
https://en.wikipedia.org/wiki/... [wikipedia.org]
Re: (Score:2)
Prior art are any wavelength shifting materials.
That is, any of the phosphors used in those "white LED" lamps, WLS materials in optical fibers and so on.
So now we have... (Score:1)
Re: (Score:1)
Pretty sure all lenses are see-through.
So they glow in IR... (Score:5, Informative)
These are not image forming. The contacts just emit visible light when they are subjected to IR.
Subjects were able to perceive the direction of an IR light source while wearing the contacts. Which I figured must be the case. They would have to get the light to form a focused image on the retina for it to be an image forming system. Considering that the nanoparticles are getting lit up and are re-radiating in random directions, there is no way it would form an image.
Re: So they glow in IR... (Score:3)
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Another advantage is letting natural light through, only adding a glowing halo on IR emitting objects. They illustrate the goggle idea first figure of the paper. The would seem to me a much better idea than the luminescent lenses, except for their very specific described use case of picking up Morse code without others seeing it.
Re: (Score:2)
Unlikely. CCD's sensitivity is down in the individual photon range. Thermodynamics says you can't upconvert fewer than two photons without a power source and various other physical limits mean any type of medium is going to be way, way worse than that. Passively detecting near IR is kind of useless too, so the only way you're using goggles made this way is if you've got a
Nothing to see here⦠(Score:2)
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how? (Score:4, Interesting)
Re: (Score:3, Informative)
No "extra energy" needed. This is not a single-photon conversion.
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Yes, I would expect that as well. Probably not nearly as good as a proper IR camera, which you can get below $100 off Aliexpress these days. Well, probably not in the US with the tariffs...
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It's near IR so the bodies have to be a couple thousand degrees to start with. THEN they also have to be quite intense for you to actually see them.
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Good point. My Physics-Fu is weak in that area.
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How can a passive device convert a lower frequency and therefore lower energy light into a higher energy light? Where does the extra energy come from?
Just a guess: It converts strong IR light into weak visible light?
Re:how? (Score:5, Informative)
By accumulating the energy until it reaches a threshold where it is emitted. Like most everything else that can be "charged" by light and release it by glowing later.
This isn't converting the wavelengths of IR to some other wavelength like a filter. It just kind of soaks up IR light and glows it out as visible light. And even then it is taking an extremely strong source of IR light from an LED to work. You know how you can close your eyelids and still see a bright light like the sun glowing non-distinctly? It would be a lot like that. The glow is so faint that it really can't be seen in a bright light environment, which is why it works better with eyes closed (again, with a bright spotlight-like source of IR beamed at the eye).
Neat, but this isn't going to turn you in the the Predator seeing in IR or something.
Re: how? (Score:2)
Re:how? (Score:5, Informative)
How can a passive device convert a lower frequency and therefore lower energy light into a higher energy light? Where does the extra energy come from?
The key is that these contact lenses aren't actually “passive” in the strictest thermodynamic sense. It uses upconversion nanoparticles that absorb multiple low-energy infrared photons and then emit one higher-energy visible photon. No magic: energy is conserved because you're stacking inputs—like combining two dimes and a nickel into a quarter So the lens isn't “creating” extra energy. It’s accumulating multiple infrared photons and emitting their combined energy as one visible photon. But there’s a tradeoff. That upconverted light gets scattered in all directions, so while you can see the light, you lose directional and spatial information. It’s like hearing a voice but not knowing where it came from. That’s why the image is fuzzy -- unless you engineer waveguides into the lenses or an anisotropic forward scattering array, like a directional RF antenna, all your brain is going to get is a smeared out version of the source. Enough to get a direction, but that is about it.
Re: how? (Score:2)
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There is a phenomenon called frequency doubling [wikipedia.org], which allows two photons to combine in a particular medium to produce a photon with twice the energy (and hence, double the incident frequency). It depends on the medium (usually, but not always, a transparent crystal) being tuned to the and the incident wavelength, and often the incoming light must be cohere
Nude glasses! (Score:2)
Finally, the greatest, most important research goal of all times has been achieved!
In other news, IR converting contact lenses have been outlawed and using them without special permissions can land you in jail.
Marvin (Score:4, Interesting)
Darkness won't engulf my head,
I can see by infra-red,
How I hate the night.
-- Marvin the Paranoid Android, aka Douglas Adams,
I dont like contact lenses (Score:2)
BS (Score:2)
I read about the original article somewhere, the only thing people can see is a IR light showing numbers radiating directly at them, that's about it.
New Keroshis Have Dropped (Score:2)
Investment in IR proof clothes takes off.