An innovative optical panel provided with an hexagonal array of refractive lenses having a properly optimized doublecurvature
profile has been simulated by ray-tracing and fabricated by injection-moulding. Such lenses are constituted by
a concave profile (having negative curvature radius) on their bottom and a convex profile (having positive curvature
radius) on their top. We demonstrate that, if compared to refractive elements with conventional geometry, bell-shaped
microlenses allow to collect incident rays within a wider angular range (so reducing the number of rays lost by TIR )
and to properly re-direct them. When installed on fluorescent tubes-based professional lighting systems, such refractive
elements allow to reduce undesirable glare as prescribed by EN12464-1 Interior Lighting Design Standards and to finely
control photometric outputs of luminaries.
Besides, bell-shaped microlenses-based films were also simulated to be applied onto a bottom-emitting lambertian
OLED. We demonstrate that, by properly tailoring both concave and convex profile shape, it is possible to increase the
outcoupling efficiency, as well as the luminous flux emitted by the exit surface, by a factor up to 1.95 and, at the same
time, to produce far-field photometric outputs characterized by uniform isocandela distribution maps with an aperture
angle up to 60°.