I like incandescence-- but I don't think it it's the essesnce of light-- I would suggest luminous.. or lucent-- which of course, is just closer latin word for light (light coming in from OHG--from the latin luc-)

I especially like luminous-- since its seems a cooler word-- it frees light from the heat (of the sun, and from the heat of incandescence) the moon is luminous. and it keep a sense light as shiny-- like silver or gold. and luminous sound ethereal-- or it does to me at any rate.