Introduction: Hologram Projector
Hello and welcome.
Holograms have been apart of sci-fi stories for as long as there's been sci-fi stories. Holograms are a cool and immersive way of viewing images and videos. Holograms are just plain awesome! And who doesn't want want one for themselves?
That's why today I'll be showing you how to build a hologram projector that you can actually stick your hand through. Not like those hologram projectors that use clear plastic pieces shaped in rhombuses to reflect the video (Although, that is a good starting point).
This hologram projector is the closest thing to a real one that you can get (on a low budget of course). This uses a convex lens (a magnifying glass) to reflect the light from your phone and makes it look like it's trapped it in mid air.
(x1) Magnifying glass (Convex Lens) (You can find these at the dollar store)
(x1) Phone (To display your holograms) (You can find hologram videos on YouTube by typing in: 180 hologram video)
(x1) 3D Printed Hologram Projector (Can be found here on my Thingiverse page)
(x1) Small Screw and Nut (Used as a pivot to adjust the angle of the lens)
Step 1: How It Works
Take a magnifying glass and hold it up to the light. If you look at it from the right angle it should look like the light is being displayed in mid-air.
Refer to the image above. It's really hard to capture this illusion on camera so you'll just have to see it for yourself by trying it.
Now, you may think that the light actually being displayed in mid-air, but it's actually just reflecting/being displayed onto the center of the convex lens (the magnifying glass).
If you refer to the image above, the focal point is where you should see the hologram because that's where all the light converges to display (or render, for lack of better words) the image. That's why the image/video appears to be floating in mid-air.
Try putting your finger on the middle of the glass. You should see the light disappear or be blocked. Now there is no holographic illusion. But as soon as you remove your finger, you should see the holographic illusion again.
Now try tilting your head all the way to the side of the magnifying glass. You should now see the light being displayed "inside" the lens. Now it doesn't look like a hologram. But as soon as you move your head back and look at it head on (line up your head and eyes with the center of the lens/magnifying glass), the holographic illusion should return.
Therefore, the drawback to this design/concept is that you can only look at the lens head on or look down at it in order for the illusion to work.
Side Note: I don't recommend staring at the hologram/illusion for long periods of time as it may not be easy on the eyes. I know if I stare at it for to long (especially in a dark environment) my eyes start to strain. But this also depends on how bright the light source is and how big/small away the actually image/display is. If you have a super bright screen, your hologram display should turn out clearer and be a bit easer on the eyes. If your screen's not that bright, then your eyes need to work harder to see the display.
Step 2: Assembly
The assembly is pretty simple.
Print the parts needed (Can be found here) and assemble them as shown in the image above (The black square is a quick design of a phone).
The magnifying glass should fit into the Lens Holder.
Now, take the Holo-Projector Mk-1 Half Lens Cover and place it on the top half of the magnifying glass.
Put a nut and bolt through the hole and adjust the angle of the lens to your liking (I went all the way down until the Lens Holder hit the table. Should be around a 20-30 degree angle).
Turn the brightness all the way up on your phone, place it on the Hologram Projector, and play the 180 hologram video.
You should see the video playing in mid-air.