In TWOK we see this graphic when shields first go up. An enhanced network of lines in the area around the bridge.
http://movies.trekcore.com/gallery/a...7/twok0433.jpg
When the prefex code is used to drop Reliant's shields, we see this.
http://movies.trekcore.com/gallery/a...7/twok0571.jpg
Based on what Timo posted I'd say the latter shows the screens as they surround the vessel. The former example is a shield, an extra layer of protection around certain areas. We only saw the bridge, there are probably others.