IndianRingNeck.com

is this true

Special UVA and UVB compact fluorescent lamp for use with all captive birds.
UVB allows birds to synthesize vitamin D3 in their skin.
UVA helps bird's curb feather picking and other destructive behaviors.
Without UVA birds are colorblind!

The sun light (real or artificial) also is necessary for their eyes to see a full range of colors.. It is all around good for them. I have a Avian UVB lamp for my two boys and they love to sit underneath of it and bask all the time, especially after bathing. They sit right under it and preen. It is good for them. But expensive and the bulbs only last 6 months before they have to be replaced.