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Polarized Screens to Hide Sensitive Data
NiugMan writes "NewScientist.com reports that Iizuka Denki Kogyo, a Tokio-based tech company has developed a monitor which appears to be blank if you stare at it with your eyes. Only by wearing a pair of polarised glasses you see stuff on it. The idea is to protect sensitive data from unauthorised personnel. Please take your special glasses with you when you take a coffee-break."
> The cost of polarized system is too high
> and is certainly not justified.
Actually, all LCD monitors *already* have the capability built in. The way they work is by using the polarization of light. All you have to do to make one of these "secure" panels that can only be viewed through polarized glasses is *remove* the polarizing film from the monitor.
Put simply, it should not be much more expensive to *leave out* part of the panel, eh?
I just love the cost of these monitors ...
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Um, put a polarizing filter on the monitor, add a simple 90 degress polarized light source to the front of the monitor (translucent sheet) put on your polarized glasses and you are set.
Sounds like bad security practices to me
Btw. The gentle fisher folks have been using polarized sunglasses for spotting trout for years
TastesLikeHerringFlavoredChicken
Smiley or not, that's actually a brilliant idea, that would render all of those sixteen hundred dollar and up monitors (for just 15"--sheesh) useless from a security standpoint.
Wearing polarizing sunglasses and tilting your head would be very conspicuous, to say the least. But polarizing contact lenses would work perfectly in this application. (This 'application' being the misappropriation of sensitive information.) It's not a trivial task to prepare them, but it's certainly not out of reach of a person of above average competence. If a person has naturally dark-coloured eyes, the added shading from the polarizers wouldn't even be apparent.
Need a quick and dirty solution? Look at the reflection of the monitor in a piece of plate glass. A blank acetate sheet will do in a pinch. Reflection off of a clear material will separate the two orthogonal polarization states of light if you adjust your viewing angle correctly. Sure, the information will be backwards, but if you're just feeling a bit nosy, it's no problem. And it doesn't look like you're looking at the screen in that case.
You want to protect sensitive information? Put it behind a wall.
~Idarubicin
How does this "technology" find itself in a science magazine? When I was 10 years old I noticed that I could take the polarzing filter off of my school calculator's LCD screen, and make the numbers displayed invisible, unless viewed through the filter. As far as I know, most LCDs (like the ones on digital watches, etc.) can only be viewed if the polarizing filter is in place. This is not new technology. This is greedy people trying to sell something many people already have -- most just don't know they already have it. (Try it! Take apart any cheap digital watch or calculator -- it will have a polartization filter in front of the LCD that without which the numbers will be invisible!)
The absolutely most ill-conceived approach to security is any kind of system that merely provides a layer of obfuscation. Why? Because it creates a false sense of security. This is mere obfuscation and nothing more. If I walk in to your bank wearing my driving sunglasses will the security guards have me arrested? Probably not. I wouldn't stand out at all -- yet my completely normal sunglasses would crack this so-called "technology". This is not secure. Secure means that NO ONE has the technological nor financial means to break the security system -- not even governments.
Anyone can buy polarizing sunglasses very cheaply these days. I've seen pairs at the grocery store for about $12. Hell, you can even buy a polarzing filter for your camera for around $25. Anyone can view and take photographs of the information displayed on these screens with off-the-shelf products. I bet your bank's owners would be pretty damn upset if the new security system you recommended, and they spent hundreds of thousands of dollars on, was foiled by a 10-year old with a $12 pair of glasses.
Despite what EULAs say, most software is sold, not licensed.
I've been meaning to get this on Slashdot for some time now, but I worked on a much more powerful version of such glasses over a year ago at Mitsubishi Electric Research Labs (MERL) in Cambridge, MA, with Researcher William Y. Yerazunis. Here's the technical report if you'd like to see it. We also filed a few patents way back then as well, so I wonder if this work infringes on our own.
We can actually hide secret images within any image or animation you'd like, not just an obvious blank screen. We also designed a cryptographically secure version which isn't cracked by simply having another pair of special glasses (you also need the private key). Check out the paper, it has some image examples (there might be a few technical errors in it that we later fixed but wasn't updated in the paper. I'm not at MERL anymore, so I haven't bothered checking really).
Also, we made a video demo for the conference which our technical report was accepted in paper form (at OzCHI2001). I have that video, and can digitize it if there's enough demand. By the way, while I was testing the glasses, I actually used They Live screenshots so that one could simulate Rowdy Roddy Piper's shock upon seeing the billboards and aliens. Also, we referenced John Carpenter in our paper.
The only true currency in this bankrupt world is what we share with someone else when we're uncool. -Crowe