Wednesday, May 11, 2016

The 3D hologram on the smartphone actually works!

A colleague of my classmate showed me an article & video of a hologram created on a smartphone, and I didn't quite believe it.



It did make me curious though. Holograms & VR are something I'd love to work on, so I actually tried it out.

Find a CD case or even transparent plastic or glass. Perhaps even a plastic bottle as one person did.


Cut out four pieces of a trapezium from it. Drawing a diamond shape as shown below is by far the most convenient and space-efficient way of doing it. Once you've cut it out on paper, stick it to the plastic with cello-tape and carefully cut the plastic.
 
You end up with this

Super-glue would be a better option for sticking it, but I just used cello-tape. Make sure the 1cm edge part is even, because that's the part you'll be keeping on your smartphone.

Now take your pick from the various videos available.


and watch it come alive!






Turns out there are far more impressive holographic illusions than the smartphone illusion. Play the one below and see.



And all this isn't modern technology. Such illusions have existed since the year 1584. There are plenty of examples scattered across history. More recently, holograms were used in Mr.Narendra Modi's election campaign!

It all began when an Italian scientist named Giambattista della Porta created the illusion of what later came to be known as Pepper's ghost.

This is how the illusion works:


Modern technology comes into play when you want to actually touch the hologram. As of today, that's made possible in a small way with lasers.




Beautiful!



How the smartphone hologram illusion works

In reality, the smartphone hologram is not a hologram at all. It's simply a reflection that can be viewed from all 4 sides. I remember when a person first showed me the video, my first question to him was "what happens if we remove one of the plastic panes?"

While the video is playing, try putting your finger into the middle of the plastic pyramid you created. You'll still be able to see the 'hologram' because your finger isn't blocking anything. In-fact, instead of creating four trapezium's, if you held just one pane of plastic or glass at that angle, facing you, you'd still be able to see the 'hologram'.

When you stand 2 feet in front of a mirror, your mirror image appears to be 2 feet behind the glass. That's the exact same illusion the plastic trapezium creates. At that angle, it just reflects the video, making you think the image is somewhere behind the plastic, in the air. The reflections from the other three panes aren't visible to you because they are at angles that don't reflect or refract the light in your direction. The only way having 4 trapeziums helps, is that you get to see the reflection suspended in the air, in the four directions you view it from. It also creates the illusion that an object that looks three dimensional, is contained within the pyramid shaped container you created. That's all there is to it.
Still...impressive!

Makes me wonder....could a rainbow be called a real hologram?


6 comments:

Karthik Chandrasekar said...

very cool.

Navin Ipe said...

Thank you Karthik. Hope you'd try it out too...

Unknown said...

Awesome

Navin Ipe said...

Indeed. Also do a Google search for Microsoft's HoloLens. Very impressive tech there too.

Sayan Sen Gupta said...

Hey, it works miracle!! I am even planning to create a scaled up model and using laptop screen. There are even apps which help you create your own 3d image. Good information Navin, kudos!!

Navin Ipe said...

Great to hear that! Yes, a laptop screen or a tablet would work out very well. Please do show me photos after you build it. I wonder if this technique could be used to view a 3D movie without having to wear 3D glasses...