Ledil has produced a novel LED lens specifically to reduce the length of optics in spotlights using Lumiled's K12 twelve-die package, which has a source diameter around 12mm.
Called Helena, it cuts the distance between LED mounting face and lens front to around 20mm, despite being 72.8mm in diameter and producing a +/-11° beam.
"The Helena has been designed to sit very close to light source this allowing
compact fixture design," said Ledil.
The secret is a Fresnel rear to the lens to pull in light from glancing angles.
There are 2 variants -
Helena-A is designed for a maximum intensity peak, at the expense of some wavelength and intensity artefacts.
Helena-B has some pillow texturing on the top side of the lens to widen and smooth the light fractionally.
K12 lighting LEDs can put out 2,541 lm (700mA, 5,000K, 33V).
