Check out this article:
http://www.ascmag.com/magazine_dynamic/June2009/StarTrek/page1.php
Here's a quote from page two: "Much of the lighting built into the interior was designed to cause lens flares, which serve as a visual motif throughout the picture. “The Enterprise has lights set in frame that
basically point down the lens of the camera in every direction,” says Mindel. “Wherever you look, you get a flare."
I added the underline.