A Multisource Regular Dodecahedron Solar Simulator Structure for Uniform Flux

In this paper, a regular dodecahedron solar simulator structure with five spot light sources is presented to provide uniform flux. To analyze light distribution without a dodecahedron cavity, a cubic cosine relationship between deflection angle and test flat plane is proposed, and results show that nonuniformity reaches 5%. By introducing a regular dodecahedron cavity, nonuniformity can be reduced to 2% in a circular area with an 85% inradius, according to the Monte Carlo ray tracing method. Based on the structure, a prototype simulator is fabricated by pentagons with 4 cm inradius and with five high-power light-emitting diodes (LEDs). Across the inscribed circular aperture of the bottom light output pentagon, nonuniformity is 3.1%; while 2% nonuniformity is reached in a 3.4-cm
²
circular aperture whose area occupies 72% of the inscribed circle.