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Instructables user dimovi took an old LCD monitor and moved the top polarizer from the surface of the screen to a pair of glasses worn by the user. Others who look at the monitor, without the polarized glasses, see only a white rectangle. Besides the übergeek cool factor, the mod could be quite useful if you’re concerned about folks looking over your shoulder at the coffee shop.

(If you’re scratching your head right now, and could perhaps use a brief refresher on how liquid-crystal displays work, you’re unlikely to find a better one than Bill Hammack’s excellent video on the subject.)

Sean Michael Ragan

I am descended from 5,000 generations of tool-using primates. Also, I went to college and stuff. I write for MAKE, serve as Technical Editor for MAKE magazine, and develop original DIY content for Make: Projects.



  1. Andy Callaway says:

    Of course, if you already have a pair of polarised sunglasses you can skip the glasses step.

    1. Yes, if the axis of polarization of the glasses matches the top polarizer from the monitor.  I understand most sunglasses are polarized in the vertical direction, but I dunno if there is any standardization in the orientations of the two polarizers on an LCD panel.

      1. Anonymous says:

        My sunglasses are polarized on an angle, has a funny effect when I turn my head when looking at monitors and they just go black. The extreme of that was when I was at an airport and didn’t notice a departures LCD display was on until I had my head on a slant.

  2. I don’t think the coffee shop would take all too kindly to you taking apart their monitors.

    I will however brand this as the best employee procrastination tool yet …actually, I don’t think your boss will like you taking apart monitors either.

    I’m trolling, cool shit ;)

  3. Ian Patterson says:

    That is awesome. 
    I was literally thinking about this less than a week ago.

  4. Anonymous says:

    I did something like this in math class in grade school. We weren’t allowed to use calculators, so I removed the top polarizer from the LCD display and wore polarized sunglasses. The teacher never understood why I brought a “broken” calculator to class, but he still removed my calculator from me.

  5. Incredible, it seems an act of magic :)


  6. johnson says:

    wow, ges wht? i got a lcd monitor with peeled off polarised film….i want a new film any givers?