Pan-and-tilt head of the heliodon
at the University of North London

Heliodons are used to simulated the path of the sun. Sunpatches entering through a window could potentially cause glare problems. This can be tested under a heliodon.

Heliodons consist of two essential parts:

• a table that can be swivelt and tilted
• a light source on a vertical scale

There are three variables that must be controlled in order to simulate the exact position of the sun:

• The geographical latitude of the place is set by tilting the table around its horizontal axis,
• The time of day is set by rotating the table around its vertical axis.
• The season is changed by moving the light source up and down.

Detail of the heliodon at UNL