Optical illusion

HOW

1. Observe the area above the central part of the device from a slight angle.
2. Change the observation point until you see an image of the object that is in the device.

WHY

There are two parabolic mirrors under the safety glass. There is an object in the middle of the lower mirror. The upper mirror has an opening in the central part through which beams of light enter and, at the same time, beams exit to form an image above the surface of the glass.