Could a homebrew LCD privacy hack lead to a new way to make tablet screens?

Could a homebrew LCD privacy hack lead to a new way to make tablet screens?
A few days ago the folks over at Hack-a-Day highlighted an article on Instructables that shows you how to hack an old LCD monitor and convert it into a privacy screen. Now the question is, could this be a viable solution for those who need more privacy on their tablets in public situations?

The idea is pretty simple. Basically, inside the LCD screen there is a layer of polarized film that enables us to see what is being generated on the screen. By removing that layer and installing it onto a pair of glasses, the screen always appears white to onlookers, while the person viewing the screen through the glasses can see the actual screen images.

Now, of course, potential spies could manufacture their own glasses and people typically don’t jump on the opportunity to wear glasses, as seen in 3D technology advancements. On the other hand, tablets are making their way into more situations where privacy is paramount. For example, as many medical professionals begin using tablets in their practices, wearing a pair of special privacy glasses to give patient’s sensitive medical information an extra layer of security seems very reasonable.

No one knows for sure if tablet manufacturers would consider adding a physical privacy guard to their displays, but, at the very least, if you’re looking for a fun project and have an old LCD lying around, check out Instructables to make your own privacy screen.

source: Instructables via Hack-a-Day



1. Lucas777

Posts: 2137; Member since: Jan 06, 2011

eh it wud only be useful if u could turn this on and off when you wanted to

2. douglasman100

Posts: 24; Member since: Aug 27, 2011

yeah i agree with you also i think that if they could make the screen remain black it would be awesome

4. Lucas777

Posts: 2137; Member since: Jan 06, 2011

it wud. but just think about if u wanted to show ur coworker or even the patient as this article describes

8. fervid

Posts: 183; Member since: Nov 22, 2011

LCD needs light to function. A black screen would not work. They could do like some watches and use a reflective background or instant on light you can control, but without light shining through the polarized layer you have no image.

3. ElectroManiac

Posts: 47; Member since: Sep 29, 2011

Porn will be much better with this. Umm I have an old LCD here.

5. remixfa

Posts: 14605; Member since: Dec 19, 2008

medically, its not reasonable. Its just another expense. Anything used in the hospital situation needs to be disposable. As you enter and leave rooms you put on and then dispose of all sorts of stuff to reduce contamination. I had no idea before I started my clinicals just how much hospitals throw away every day from patient to patient. I'd be surprised if the glasses didnt reduce visual acuity even a little bit, and that could be dangerous. I love the "idea" of it, but the actual use of it in medicine would be more dangerous than beneficial.

9. fervid

Posts: 183; Member since: Nov 22, 2011

Pretty similar to the 3D glasses theaters charge you extra for then have the recycling boxes outside when the CEO of Real3D specifically says they can't be recycled. I'm picturing some 3rd World country labor in the back of the theater polishing them up and putting them back in new bags for the theater to sell again. What ticks me off is they try to claim the cost is just for the glasses, but if you bring your last pair in again they still charge more. They are just polarized glasses like these and not the active shutter battery things like with some TVs, so they don't go bad...I'd say the waste of the glasses at hospitals and theaters would be a pretty close tie.

10. remixfa

Posts: 14605; Member since: Dec 19, 2008

hospital glasses cant be cleaned and reused (as im pretty sure those theater glasses they have to be put in medical waste bags and thrown out with everything else like gloves n gowns. As soon as you are ready to leave a patients room, you take everything off and throw it away.. every time... even if you were in there for just a second, or you risk contaminating another patient in the next room you go to.

6. MOTOROLA_is_Cool

Posts: 9; Member since: Oct 30, 2011

Cool New privacy Lcd screen,Now no one above your shoulder can see content unless they has the glasses :)

7. fervid

Posts: 183; Member since: Nov 22, 2011

Polarized glasses have been out for some time. Many people may even have a pair and not know it. They are usually used for fishing a lot since they reduce about 90% of glare and reflections. I use them while driving all the time because they remove the dash reflection off the windshield. They make clouds and the purple anti-glare tint on windows look odd as well as being able to see some imperfections in glass more too. The big thing is what direction the polarization is. The new 3D glasses use a circular type while LCD uses straight lines. If the mfg makes the lines the wrong way then it turns the screen black when looked at through certain sunglasses. My Nissan Rogue, most gas pumps and a couple of watches were made this way and I have to turn my head sideways and look like an idiot to read them. Since most glasses are made in-line with the type used on LCD screens anyone with a pair of sunglasses will be able to read your private documents you think are safe. They can be made completely clear though, but you may also have the same issues of turning some screens black if the polarized lines are wrong on that screen, so they could cause problems in a work place setting.

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