UV lens protect the primary lens of your camcorder. Its cheaper to change the UV lens than to change the camcorder lens.
Another effect of UV lens can be seen here:
Polarized lens comprise of UV + skylight (2 layer glass lens). The other type I supposed is the flourescent lens.
So, if you're using for indoors there's no requirement to have the UV lens if you've the polarized or flourescent screwed on.
You can visit here to read more about camcorder accessories:-
I understand the UV lens will help protect the expensive lens. I see three kinds of lenses. UV, polarized, and some kind of indoor light lens. Do they work?????
Should I only worry about keeping the expensive lens clean?? If so, how much should I spend to keep the lens clean. I have seen the lens to keep things clean, for as much as $30.00, and as little as $9.00.