Developed by : Dr. L. Michel, C. Roecker, P. Loesch, Prof. J.-L. Scartezzini, R. Rhyner in the framework of the Swiss Federal Energy Research Program LUMEN

drawing of direct sun simulator with scale model of building under sun simulating light source


The heliodon is used to examine how direct sunlight interacts with an architect’s building design. It is often used in conjuction with the Scanning Sky Simulator to predict the light distribution in a building over a whole year.


  • Comparing daylighting performance assessment of buildings in scale models and test modules / Thanachareonkit, A.; Scartezzini, J.-L.; Andersen, M. – In Solar Energy, num. 79 (2005), p. 168-182
  • Implementing the Partial Daylight Factor Method under a Scanning Sky Simulator / Michel, L.; Scartezzini, J.-L. – In Solar Energy, Elsevier Science Ltd, vol. 72, num. 6 (2002), p. 473-492
  • Performance of a new sky scanning simulator / Michel L., Roecker C., Scartezzini, J.-L. – In Lighting Research and Technology, vol. 27, num. 4 (1995), p. 197-208