Pepper’s Ghost Illusion

Trick? No, illusion! Follow these simple instructions to make a ‘floating’ image with your phone – all you need is a small pyramid made out of hard clear plastic.

The optical illusion is known as the Pepper’s Ghost effect. It works because the plastic is oriented at approximately 45° to the phone screen and reflects some of the light from the phone out towards you. Your eyes – which are used to observing that light travels in straight lines – convince you that the image is actually in the center of the plastic pyramid. The illusion is named after John Henry Pepper, who popularized the technique for theatrical productions in the mid-nineteenth century. But it’s still used today, including on rides at Disneyland!