Installing Backup Lights

Look at the cones surrounding the tiny yellow CREE chips.
The ones on the left have concentric rings
The ones on the right do not

The ones on the left help make a lamp disperse light much wider and taller (flood light)

The ones on the right make the lamp illuminate much further distance. Spot light.

Can you guess which one would make a useful backup lamp and which one would would merely drill narrow thin holes in the black of night?

Backup lighting really deserves DISPERSION LENS which is frosted plastic sheeting but the stuff is hard to find. I became an Original Equipment Manufacturer for Lumilux because conventional CREE lamp design did not allow for wide dispersion.

Hope this helps...