1. A light-emitting diode (LED) lighting system comprising:a holder comprising:
an aperture having a perimeter, and
a fillet adjacent the perimeter of the aperture, the fillet having a radius greater than or equal to 2.0 mm and less than or equal to 4.6 mm; and
an LED array mechanically coupled to the holder, the LED array having a light emitting area exposed through the aperture.