• akwd169@sh.itjust.works
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    4 months ago

    demonstrating that he can point a laser that’s invisible to the human eye at a faraway laptop, through a window, and detect the computer’s vibrations to reconstruct virtually every character typed on it

    Infrared is not visible

      • akwd169@sh.itjust.works
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        4 months ago

        Ahh ok, that’s what you meant before I guess

        Since that function is usually meant for night vision, I wonder how well a security camera can pick out the laser during the day i.e. when the IR sensors are being swamped by daylight also coming in through the window

    • Sneezycat
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      4 months ago

      Infrared doesn’t pass through windows.

      • HubertManne@moist.catsweat.com
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        4 months ago

        actually thats UV. transition lenses won’t change with a glass window thats not open. infrared is basically heat and does indeed pass through. Cars in the sun would not get hot so fast if they did not let in infrared.

          • HubertManne@moist.catsweat.com
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            4 months ago

            yeah I encountered it when looking at infrared for another convo in the thread. its uvb for what we think of as glass. the clear stuff. which is what causes sunburns and the transition lenses to activate.

        • Sneezycat
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          4 months ago

          I have an IR camera and windows look like mirrors. Might depend on the type of glass idk.

          • HubertManne@moist.catsweat.com
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            4 months ago

            if this yahoo from the internet I found in a search is right then its both:

            “Glass will bock low frequency IR (red hot), but allow the passage of high frequency (white hot) IR. Hence, the heat of the sun will easily pass into a greenhouse, but once this energy is converted into low frequency heat by the objects within that absorb it, then the resulting low frequency heat is trapped. Hence, the Greenhouse Effect.”

            • Sneezycat
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              4 months ago

              That makes a lot of sense, thanks for doing the homework!

      • akwd169@sh.itjust.works
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        4 months ago

        I’m not going to argue with you but you should read the article perhaps? It’s pretty specific about where the laser is aimed vis a vis windows and whatnot