With this neat little trick you can watch all the filth and depravity you want, even in public!

A while back before taking the Shinkansen from Osaka to Tokyo, I thought it would be a good chance to catch up on some movies I’d been meaning to watch. So, with my classic lack of foresight, I loaded a GG Allen documentary onto the old iPad and off I went onto a train tightly loaded with people.

The person who was sitting next to me on that fateful day probably would have really appreciated this little trick that has recently resurfaced in Japan. Using it you can alter your display to show only white light unless you are wearing a special set of glasses.

Here, Twitter user Yuki has pulled off the effect quite well.

▼ “I did it. With this you can surf the net without worrying about prying eyes!!”

https://twitter.com/yk_ichinomiya/status/899892428341075969

This bit of magical privacy is achieved through the way typical LCD (liquid crystal display) screens are constructed. Most light from the sun, light bulbs, or that twinkle in your eyes is actually a big messy wad of electromagnetic waves pointing this way and that. This is also the case with the source light for LCDs.

However, these screens also use polarizing filters that work like a Play-Doh fun factory and squeeze out a thin horizontal strip of light. Then, depending on whether the crystals are “turned on” or not, they will bend the light into a vertical strip that can pass through the second polarizing filter oriented in a vertical direction.

Here’s a handy video that illustrates this process to some relaxing music. Actual filters aren’t really horizontal and vertical but more like 45 degrees and 135 degrees. This is just for simplicity’s sake.

What Yuki did was peel off the second polarizing filter from the display of a laptop that was destined for the trash heap. That’s it!

Without its second polarizing filter, only the original tangled mess of white light is seen by the naked eye, but when you slip the filter in front of it the image is revealed. This of course is much easier said than done. Popping open your monitor and monkeying with it runs a considerable risk of damaging it to the point of uselessness.

In the tweet, Yuki is holding an inverted lens from a pair of 3D glasses used at the movies. However, others buy polarizing filters in sheets that you can cut into any shape or size. These filters are widely used in photography to reduce glare and should be fairly easy to find.

In any case you have to be careful, because not all screens are created equal so results may vary. And it probably goes without saying that this only works with LCD screens, so put the screwdriver down and slowly back away from that plasma screen.

The impressive part of Yuki’s technique was cleanly pulling it off on a laptop. Many people on Twitter are asking how that was accomplished, but as a talented illustrator as well, Yuki decided to put the method in doujin form and sell it during Tech Book Fest in Akiba Square on 22 October.

If you do insist on giving it a try, research it thoroughly before proceeding and use a screen that you can live without.

Otherwise, you can always keep away lookie-loos the way I did on the Shinkansen that one time my neighbor was trying to get an eyeful of my documentary: take off all your clothes and throw feces at them.

It’s admittedly low-tech, but highly effective. Thanks, GG!

Source: Twitter/@yk_ichinomiya, NetLab
Featured image: Twitter/@yk_ichinomiya