This is a video of the beam pattern of an HD2010 as an opaque object is passed in front of it. You may be surprised by the result, but then maybe not.
that is pretty cool, i figured the hot spot was going to be cut in half when it was dead center. nifty experiment
That makes sense. A lot of the spill is the light that is emitted from the emitter towards the front of the light. Basically the light that is emitted from the LED that then just passes through the lens without hitting the reflector at all.
The spot is composed mostly of reflected light…… light that is emitted sideways and bounces off the reflector.
Cover up the center of the lens and you get less un-reflected light, so less spill.
This is damn cool. Just tried it.
Try passing a mirror instead. Can anybody predict what happens then?
The spot comes from the reflector, ie light is emitted sideways and at an angle from the LED, not straight out. It hits/reflects of the reflector and is focused into a spot.
The hotspot is coming from the reflector, from multiple angles on each side/point because the led is not a point source. Hence blocking half the reflector only blocked half the amount of reflection. I discovered that a long time ago when I was new with flashlights. I play with them in the room with all my lights tuned off at night.