This is your problem; OS X's default setup for multiple monitors is to give you additional desktop space on Display 2.
1.Go to System Preferences -> Displays, second tab has a checkbox at the bottom for "Mirror Display". This puts your desktop on both screens.
2. [On the same tab] If you want the Bravia to be your main display and your MBP screen to be secondary, drag the small white menubar from Display 1 to Display 2.
3. If you want JUST the Bravia as a display, plug a keyboard, mouse, and power into your MBP, shut the lid, let it go to sleep, then wake your MBP back up by hitting a key on the keyboard. This puts it in clamshell mode and uses your external as the only monitor.
Edit: If you dont want to go to clamshell mode, use step 2 and dim your MBP's screen until it goes dark. I usually set up like this if I want to watch a movie on my TV and don't want to move everything off my desk to the living room. Eat your heart out, Apple TV!