Invisibility Shield

So, you want to make an invisibility shield, eh? Of course you do! Who wouldn't want the ability to become invisible? Watch the video above to see the fun you can have with an invisibility shield made from a sheet of Lenticular Lens. Are you excited yet?!

Get started making your own by ordering your supplies:

Supplies

• [Quantity 1] Lenticular Lens Sheet: 40 x 28 inches (711 x 1016 mm)
• [Quantity 2] Liquid Optically Clear Adhesive: 50 ml, low viscosity, you need 2 vials
• [Quantity 1] Polycarbonate Sheet: 1/8 x 48 x 48 inches (3.2 x 1219 mm)
• [Quantity 1] UV Lamp: 100 W
• [Quantity 4] Optically Clear Adhesive Sheets: Any size is OK, you need 4 sheets
• [Quantity 1] Rubber Roller: Optional, but highly recommended for the glue process
• [Quantity 1] Film Removal Stickers: Optional, but recommended for working with OCA sheets

Step 1: Cut the Polycarbonate

First you need to cut your shield and handles out of your piece of polycarbonate, following my PDF drawing (below). You can use a CNC table router if you have access to one, or you can use a hand-held router, reciprocating saw, bandsaw, circular saw, handsaw, or even a well trained beaver with sharp teeth who likes a good challenge.

Special Note for CNC or Hand-Held Routers: It's fine to leave the internal corners rounded. Mine were, and the results were great! The little radius was barely visible when compared to the overall size of the part. I used an 1/8 inch diameter O-Flute bit from Onsrud, it cuts sooo goood.

Step 2: Bend the Tabs

Next, bend your tabs back. The exact angle is not important, just bend them far enough so that you can't see them when you're looking at the front of your shield.

What's that? You've never bent plastic before? With most plastics it's pretty difficult, but you're in luck because you're using polycarbonate! This plastic is really easy to bend and you don't need to heat it or do anything special, just bend it! While you're bending, you might feel afraid it's going to snap.... but don't worry, it won't snap because polycarbonate is special like that. It's the bendable plastic of your dreams!

I bent my tabs using a bending machine called a finger brake, but you can use a shop vise or whatever you have available to you. I even bent one of the tabs just using my bare hands during my prototyping process. I just tapped into some leftover teenage angst and pushed with all my strength and it bent! I'm not a super strong person. As you can see in the photos my body was mostly designed for typing, so you can probably do it too.

Step 3: Glue the Lenticular Lens to Your Shield

Remove the oddly satisfying plastic film from the front of your shield, and set it on some boxes or whatever you have nearby to raise it off the floor.

Make sure your shield and lenticular sheet are clean of dust before you proceed. I wiped mine with a microfiber cloth sprayed with alcohol, but you can also use a paper towel.

Next, take your two 50 ml vials of Optically Clear Adhesive, and spread the glue on your polycarbonate in the pattern you see in my photos. The pattern helps prevent air bubbles. To get all the glue to come out, you'll need to push the plunger all the way into the vial using a pen or stick or whatever's handy.

Now, carefully place your lenticular sheet onto the glue. The lenticular sheet has a smooth side and a side with ridges. Make sure to place the smooth side against the glue, so the ridges are facing away from the shield.

Use your hands (or a roller, if you purchased one) to push down HARD on the lenticular sheet and force the glue to spread out and fill the entire air gap between the polycarbonate and the lenticular sheet. If you see an air bubble in the glue, press down hard and squeeze and push that bubble to the edge of the sheet where it will pop and disappear. Special Note: The roller makes this much, much easier because it concentrates your forces to produce a higher pressure. I hope you bought the roller! I did the first one without the roller and my muscles were really sore the next day.

The glue gets everywhere so when you're done, carefully clean any glue mess from your shield using a paper towel or microfiber cloth soaked in alcohol.

Step 4: Cure the Adhesive With UV Light

Hang your UV light above your shield. I used a backdrop stand and some spring clamps, but you could use a broom handle suspended across two stools, or whatever you have handy. The UV light should be about 10 - 20 inches (25 - 50 cm) from your shield. If your light is too close, the light won't spread to the edges of your shield.. but if it's too far, the light won't be concentrated enough to cure the glue.

Turn on the light and let the adhesive cure for 24 hours. Depending on how powerful your light is, you might find that some adhesive towards the edges of your shield is not hardened even after 24 hours. If so, move your light above the uncured section and wait another 24 hours.

Finally, remove the last layer of protective film, and clean any last bits of uncured glue with a microfiber cloth or paper towel soaked in alcohol.

Step 5: Attach the Handles

Cut your Optically Clear Adhesive (OCA) sheets so that they are about 1/4 inch (6 mm) less than the width of your tab. This will make it easier to align.

Your OCA sheets have not one, not two, but THREE glorious protective films. Remove the first two layers (the widest and second-widest) of protective film to expose one side of the adhesive. Now stick the OCA sheet to the tabs and press down hard to get a good bond.

Next you need to remove the final protective film from the OCA sheet. This one is super hard to get with your fingernails. You can do it by carefully using a utility knife or hobby knife to peel it back, but be prepared for a little frustration. Instead, if you bought the optional OCA film removal stickers, stick one to a corner of the film and press it down hard with your fingernail to get a good bond, then slowly peel back the film and you'll see how amazingly easy this step is with the right tool (the film removal stickers).

Finally, remove the protective film from your polycarbonate handles and stick them on to your tabs. Press down super hard with your fingers to make sure the adhesive sheets bond well to the polycarbonate.

Step 6: Become Invisible!

Have fun becoming invisible. Remember, with great power comes great responsibility.

This magical illusion is pretty easy to use, as long as you follow this one weird trick: The background really needs to have strong horizontal stripes. It could be stairs, aluminum siding, bricks, a chair rail on a wall somewhere, a dark TV on top of a single-color stand, really anything that has clearly visible horizontal stripes.

To see more of my fun projects, follow me on YouTube, Instagram, Twitter, Facebook, or subscribe for email updates when new projects come out.

Comments

[Nerd]

how much would this cost

[IanCharnas]

If you can find polycarbonate and a UV light, then you only have to buy the lenticular sheet which is $80 plus shipping. Some people just buy the sheet and skip mounting it to anything. You can hold it up with your hands and get much of the effect.

[Nerd]

ok thanks I now have a Uv light so this I might do

[AnnetteA13640]

Hello, wonderful instruction! Just curious, what does the person standing behind the shield see? Is this like a two way mirror? You can see out, but they can't see in?

[IanCharnas]

Interesting question! Behind the shield you just see a big blur. It's a one way optical effect.

[raymondelegua35]

What side should face me with the sheet I ordered???
There is a soft side and a rigid side?

[IanCharnas]

Good question! The smooth side should face you, and the side with the grooves should face away from you.

[veryrealperson]

What happens if you make a cylender or dome? Can the venticular lenses be domes instead of peaks (at the more micro scale)? Can you use this in combination with electronics to pick what gets pushed to different viewing angles?

[IanCharnas]

Interesting idea! I'm not sure what would happen if you made this into a cylinder or dome.

[DMarkD]

Hi there dude,
Is it possible to use the overlay screen from an older big screen TV for the lens? I've got one from a 48 inch projection TV of the type that had the three primary colors projected though prisms and lenses into the back of what looks more like a fresnel lens.
Thanks for what you do!
Capt Mark

[IanCharnas]

Hi Capt Mark, great question!

I could be wrong but I think those overlays were fresnel lenses, which are different and won't produce the "invisibility" optical illusion

[AceIsAwesome]

Awsome I use it in hide and seek

[one-two-1-2]

Hi i was wondering if you can get a 4 x 8 lenticular lens sheet?

Thanks in advance

[IanCharnas]

Hello! Great question. I searched around for a 4 x 8 foot lenticular lens sheet but I couldn't find one.

The largest size I could find was 40 x 28 inches, which is available here: https://www.etsy.com/listing/924360012/large-lenti...

You can put several of them side by side to effectively create a larger sheet.

Hope this helps,
Ian

[brianchadorourke]

I like this. I wonder if I could hide my house.

[Rex6]

Great info. Looking forward to my sheet! Two questions: Can I use a surplus clear riot shield to make my life easier? I would really like to avoid messing with UV lights and stands which I don’t have. Can I use another adhesive? Thanks!

[IanCharnas]

Thanks! Yes a prefabricated polycarbonate shield should work fine as a base. The downside is that the handles may be slightly visible, and you may lose some surface area, but I think you can still have a lot of fun with that and I agree it's easier.

Instead of the UV lights it should be possible to just use sunlight. I believe it has enough UV content to cure this glue. I'm not sure how long it will take. Just wait until you can't feel any tackiness.

best,
Ian

[himangee]

Amazing!!🤩 My mouth was literally open all the time..
Want to make this one but don't have things to make it.. So sad..😢
Thanks for sharing!! :D

[Xxtwilight2468xX]

Same! I was speechless!!!!!

[Revathi_Kannan]

No worries. If you have a laptop you can do one of this kind. Check out the link:

https://www.instructables.com/What-If-I-Get-an-Invisibility-Cloak-As-in-Harry-Po/