I was sent a link to this page on the Metro by my good friend Gareth ( @gabundy ) & there seems to be a bit of interest at the moment in making these things to turn your smartphones into 3d hologram generators.
Firstly, they don’t.
The effect is not new. In fact it’s hundreds of years old. The illusion of an image floating in mid-air is caused by a reflection of a brightly lit object against an ‘invisible’ glass panel.
That aside, it’s a cool effect and I had a go at making one today.
The various instructional videos call for making the hologram pyramid from an old cd case. That’s great if you want to use it with a smartphone but I wanted something bigger, so I checked in the shed and found some left over Acrylic. At 5mm thick, it’s quite sturdy and would make the final piece quite “robust”.
Checking on the instructional video, it calls for four identical trapezoidal shapes, with a 1cm length at one end growing to 6cm at the other (separated by 3.5cm). Not nearly big enough for my liking.
So after a very short time with pencil, paper and a protractor, I worked out that the sides were angled at about 55 degrees. The size of my iPad is about 14cm across the face, so allowing for some framing I guessed that I would need 15cm on my largest end. That’s 2.5x the original. Now we’re talking.
15cm along the largest edge means, I need a shape that is 9cm high with the smaller edge at 2.5cm.
Using this template that I made. I scored the outlines of the pieces I would need in the acrylic and ripped them on my mini table saw.
I’ll tidy them up a bit later but for now, I’ve duck-taped them together so they form the required pyramid shape.
There are a number of videos on Youtube that you can use with this reflecting pyramid idea. Many cool ones exist on the Youtube channel for the folks at Cospe.
In a room that was not totally dark, the effect is not that good.
The two sides of the acrylic reflect the image and you get a ghosting effect on your ghost image…
…but when the room gets dark, I only see one reflection and the effect is quite dramatic.
This turned out to be a nice Saturday afternoon project. My kids found the end result fascinating.
If you’re thinking about making one of these yourself, stop thinking about and get on with it. You don’t have to follow the online instructions to the letter. Put your tinkering head on and have a go.