What is the difference between 'Light' and 'Raito'?

yes Raito= Light in Japanese. I think Viz Media like the idea of his name being translated in fact most subbed versions say "Light" even i believe.

No,No Raito is just a transliteration of Light because if 你 look at closely "L's" are usually pronounced as "R" in Japanese for example the name "Alice" would sound like "Arisu" in Japanese-Hikari does translate to "Light" but it has nothing to do with the name,that's just a translation not a Transliteration of the name,I assume his name was taken as Light because of what I stated before but it's just the oppose with the "R" changing to an "L" sound and I'll take it that was why his name was changed to Light..hope I helped a bit.