Share your experience!
Have you tried settings-apps-all-camera,force stop and clear data?
If that doesn't work then repair the phone with PCC and report back
Bridge (for Mac)
Alternatives on How to backup Xperias
http://talk.sonymobile.com/thread/36355
What software version is your phone on.
It happened to me a couple of times months ago... and a simple restart made it work once again... This hasnt happened again and I am still on KitKat 4.4.4
Got the same Problem here..
Clear Data Stuff won't work, Restart neither.. PC Companion Action didn't .
I#ll soon try going back to kitkat..
\its a new and expensive phone.. and no official statement, either though i read about that problem some times now..
Downgraded to Version 4.4..still Black Screen.. by now i'm kind of pissed..