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Finally you can do something with that old LCD monitor you have in the garage.
You can turn it into a privacy monitor! It looks all white to everybody except you, because you are wearing "magic" glasses!
All you really have tohave is a pair of old glasses, x-acto knife or a box cutter and some solvent (paint thinner)




Here is what I used:
an LCD monitor of course
single use 3D glasses from the movie theater (old sunglasses are just fine)
paint thinner (or some other solvent such as toluene, turpentine, acetone, methyl acetate, ethyl acetate etc)
box cutter (and CNC laser cutter :) but that you don't really need, I'm sure x-acto knife and a steady hand would do just fine)
screwdriver or a drill
paper towels
superglue

Step 1: Take the monitor apart

Find an old monitor that you are willing to sacrifice.
Take off the plastic frame by unscrewing all screws from the back.

I think this needs 1 more hack to be really useful.<br>We need to figure out a way to feature an image on the white screen that gets filtered out by the glasses.<br>For instance, if instead of a white screen, anybody without glasses who walked into your office would see a spreadsheet, but with the glasses you wouldn't see the spreadsheet.<br>Too complex, or is it a possibility?
<p>Print a full screenshot of the spreadsheet and taskbar onto a piece of thin, clear plastic. Convince people you can only see well with black and white, so you can make it a real high contrast print. But make sure any lines are thin. Apply this to the LCD, taking care to remove bubbles. Tehn jsut get uesd to seneig waht it looks lkie knid of srecwed up. The brain is amazing at adapting, and there is a good chance you read the last sentence naturally. Look again ^^.</p>
<p>XD do you read Cambridge research? If you raed any setcnene with the lteetrs gnoe arwy, tehn you can sltil raed it if the frist and lsat ltteres are in the smae palce as bofere.</p>
<p>XD do you read Cambridge research? If you raed any setcnene with the lteetrs gnoe arwy, tehn you can sltil raed it if the frist and lsat ltteres are in the smae palce as bofere.</p>
<p>XD do you read Cambridge research? If you raed any setcnene with the lteetrs gnoe arwy, tehn you can sltil raed it if the frist and lsat ltteres are in the smae palce as bofere.</p>
Wow that's actually not bad. Might work.
<p>The brightness would have to be kept low as well to avoid drowning out the image of the spreadsheet with light.</p>
<p>Won't work. The crystals in a Liquid Crystal Display polarize the light to one direction or another, depending on their orientation, but doesn't actually block light. But when that polarized light shines through a polarized light filter (the film or glasses), it shows black or white depending on the orientation of the crystals or the filters. Without the polarized filter it's not possible for any image to be seen. The film he removed is a polarized light filter. So basically, he transferred the function it does from the screen, to the glasses. No matter were you place the filter, it will still polarize the light.</p>
<p>Quote &quot;metal won't scratch the glass, unless there is sand or other abrasives on it&quot; Unquote<br>Since when did metal stop scratching glass? That is an interesting statement :) </p>
<p>Did your baby teach you geology? Steel, and many more metals, cannot scratch glass. Look it up on Wiki</p>
Blatantly ignorant, and attitude, your just the whole package, aren't ya?
Utility knives wont scratch glass because they are made of steel.<br>Steel is softer than glass.<br>https://en.wikipedia.org/wiki/Mohs_scale_of_mineral_hardness<br>
Does anyone know if this is possible with a laptop screen?
<p>I don't suggest you sacrifice a laptop. I will work, but its better an old monitor so that if anything goes wrong, its just a sacrifice for curiousity rather than sacrificing a laptop.</p>
<p>I don't suggest you sacrifice a laptop. I will work, but its better an old monitor so that if anything goes wrong, its just a sacrifice for curiousity rather than sacrificing a laptop.</p>
<p>I don't suggest you sacrifice a laptop. I will work, but its better an old monitor so that if anything goes wrong, its just a sacrifice for curiousity rather than sacrificing a laptop.</p>
<p>Might there be a way to work this into a laptop that has an LCD display? That's what I'd like to take to the coffee shop!</p>
<p>So now we have people walking around (seemingly) talking to themselves, and now we'll have people starring at a blank screen and laughing occasionally. ;-) </p>
That was exactly the image I had of me with one in a coffee shop. What a hoot that would be! And bloody useful too. I just don't have the skills to dig into a laptop display and do surgery.
<p>To finish a thought. I'd buy such a modded laptop. :-)</p>
<p>Gotta admit, dimovi's project is super keen. One little thing no one has mentioned: when the boss (or anybody else) walks by and sees you wearing sunglasses, s/he is either going to think you are too cool or wonder what the hell you are up to reading the same spreadsheet all day long while wearing sunglasses. ... Let's go down to HR (Human Resources hiring/firing department) ... and bring your car keys with you. LOL </p>
<p>Yes, laptops screens are made the same way.</p>
<p>I have an old flat screen monitor is would love to try this on. Is there a way to tell if it is an LCD, as opposed to other types listed in the comments?</p><p>Thanx!</p>
<p>Google the model number. The specs should say if it's an LCD display, but the sales people will tell you they're all LED displays even when they're not. LCDs are not really LED displays just because they have LED backlighting instead of older florescent, it's just an LED backlit LCD. If it's LCD it will work. Open the back. If it has white flourecent or LED backlighting behind the screen, it's LCD.... Except for very large &amp; bright displays, the may be a rear projection DLP display. OIf you see a bright bulb, lens, or possibly a mirror in there it's probably DLP. DLP will also not be a thin display. The thinnest DLP rear projection display is 11&quot; deep. They or their front-projection models are preferred more by hi-end home theater buffs because of their high contrast ratios, brightness, &amp; sharpness. When you go to a modern cinema, you're most likely viewing a DLP projection.</p>
<p>If it's color, then 99% chance it's LCD. If it's an old Monochrome, it may have a bluish tinge to it.</p><p>If it glows green or amber, it's definitely plasma.</p><p>Just test whether or not the screen is affected in any way by the Polarised Glasses before deciding to disassemble.</p>
<p>can it work tft moniter</p>
<p>yes it works for all LCD, cellphones and LED's. and TFT screen too. I did in my child hood with small &quot;digital calculator&quot;. None of my friend could use my calculator, But was master then in making calculations using the same calculator</p>
<p>It WILL NOT work on LEDs, TFTs, oLEDs, CRTs, or DLPs. It has to be an <br>LCD screen (Liquid Crystal Display), because the crystals work with <br>polarized light &amp; a polarized light filter (the film).</p>
<p>Come on. TFT and LED are both LCD.</p>
<p>I take apart &amp; fix this kind of stuff all the time for a living. An LCD monitor or TV may have an LED backlight these days instead of the older florescent backlighting of a few years ago, but it's still an LCD display, regardless of what kind of light is behind the display. A true LED, oLED, &amp; TFT display does not use liquid crystals found in LCD displays &amp; do not have a backlight behind the screen. They use a different technology entirely, so polarizing the light or using a polarized light filter wont make any difference. With oLED, LED, &amp; TFT, displays, every pixel is a tiny LED that gives off it's own light &amp; color. With LCD displays, the crystals &amp; the polarized light filer, allow or block the light to shine through from a light source behind the screen. This will only work with LCD technology, don't ruin your oLED or LED screen just because some troll here likes to see people destroy their screens. Believe me, it won't work unless you have an LCD screen. If your screen is backlit by LEDS, it's still an LCD screen, not an LED screen, regardless of what the sales people said when you bought it. Likewise, don't screw with a plasma TV either. They don't use LCDs or have a backlight either. Just like true LED displays, each pixel is it's own light source, &amp; there is no backlighting or polarizing.</p>
<p>LED as light source for an LCD display - yes, it will work.</p><p>Straight LED display (e.g. organic LED, old 8 segment calculator LED display or the other technologies Betty P3 listed) it will not work because those displays do not use polarized light.</p>
<p>Can you use polarized sunglasses instead of putting the polarized film in the glasses?</p>
<p>I would really like to know as well. I have polarized sunglasses that I'd rather use than go through the trouble of making some. But also, it would mean that others with polarized glasses could also see your monitor. </p>
<p>it depends on the orientation. it will work only if your glasses coincidentally have the same orientation as the polarized film of the monitor.</p>
<p>There's no coincidence if you plan... put the film on the monitor in the orientation needed to work with your sunglasses.</p>
<p>That would just add to the awesomeness ... looking at a white screen, with sunglasses, with your head sideways. </p>
<p>you can try. polarized films and glasses works in the same way. but glass are great built quality.</p>
<p>If you're prepared to disassemble the panel further, you can flip the polarized sheet which will give an &quot;inverted&quot; color display, like a film negative.</p>
<p>yes it works for all LCD, cellphones and LED's. and TFT screen too. I did in my child hood with small &quot;digital calculator&quot;. None of my friend could use my calculator, But was master then in making calculations using the same calculator</p>
<p>I used to flip the polarized panel over so that I had clear digits on a black background. Some digital watches included this &quot;version&quot; as a temporary trend to look &quot;futuristic&quot;.</p>
<p>It WILL NOT work on LEDs, TFTs, oLEDs, CRTs, or DLPs. It has to be an <br>LCD screen (Liquid Crystal Display), because the crystals work with <br>polarized light &amp; a polarized light filter (the film).</p>
<p>Betty, an LED monitor is still an LCD, it just uses white LEDs for backlighting instead of fluorescent backlighting. LCDs (which use TFT (thin film transistors)) polarize and then twist the polarized light allowing the light to pass through the outer polarized film at that specific pixel.</p>
<p>LEDs and TFTs are both still LCD monitors. DLP is a projector, not a monitor at all. Anything OLED is likely to be too new and very expensive, so I doubt anyone would try this trick on one.</p>
<p>I think doctors will love this, they can put the xray film on it then use as computer when needed. hehehehe!</p>
Did this year's ago with my calculator and watch - it's cool to see that the same thing works with a color lcd monitor! Nice instructable!
I did this to my watch too when I was in school.<br>I had the only lcd watch around with white numbers on a black background.<br>lcd watches were just becoming cheap and common. that was about 37 years ago....<br>
<p>Yep. You can reverse the polarized light filter too, so you get a negative image. On a calculator with black numbers, they would be white or light grey numbers, &amp; the background turns black.</p>
&quot;Year's&quot;? *shakes his robot fist at his autocorrect*

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