Email icon

The PhoTOP

SKU #TOP-415
Availability: In Stock
Shine a light on this spinning disc to make spiral patterns and more!


The PhoTOP consists of a flat disk 12 cm in diameter and a two-part aluminum spindle. The resulting spinning top has phosphorescent paint on one surface and instructions for its use on the opposite surface. It is intended to be combined with a near UV/deep purple 405nm laser pointer (included) - though part of the fun is experimenting with other light sources, even a smartphone light.

When the top is spun, the UV or other light source is pointed at the spinning top's phosphorescent surface, resulting in green luminescent spiral patterns, as well as Lissajous and other figures. It is a mesmerizing piece of kinetic art, a toy or plaything for the amusement of children and the young at heart, and an educational apparatus to illustrate principles of quantum mechanics and phosphorescence, as well as principles of pattern formation. Requires 2 AAA batteries (not included).

The PhoTOP has undergone extensive testing to meet all US safety standards. (It is intended for use by adults or children older than three years of age because of the possibility of swallowing the spindle by younger children.) The PhoTOP and its inventor, Kenneth Brecher, Professor of Astronomy and Physics, Emeritus at Boston university, have been featured in several online publications, including Gizmodo.

Q & A

You May Also Like