In the picture above we can see what seems to be a real hologram inside the upside down, open ended, 4 faced pyramid. The pyramid was made using plastic from CD covers, but it could also be made using glass. At first glance the hologram looks real if you were to consider the pyramid horizontally, but when you look from the top of the pyramid there is no real hologram.

This can be explained by the fundamentals of optics. Each plastic side of the pyramid has a reflective aspect to it. Thus, when the light projected from the phone reaches the plastic the light is reflected. But what occurs is that if we were to trace the reflections backwards, all 4 sides converge and create a virtual image at the centre of the pyramid. Unlike a true 3D hologram, there is no “inter-depth” in the image, it appears as a flat, 2D object inside the pyramid. But if you shift sides, you’ll view a different version of the object, caused by your brain seeing four different perspectives of the same image at once.

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Darshak Patel
Victoria Park Collegiate Institute, Toronto, ON
Second Prize ( 2017 High School Individual Category )

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