Hello welshferret - welcome to the Sony Forums.
Does the focus not work in both photo and video mode - if it doesn't work in either mode then it may be the case that the focus settings need to be adjusted. Information for your camera can be found in the manual here:
http://pdf.crse.com/manuals/3088340121.pdf
In particular, have a look at page 41 which shows how to turn the focus on and off and how to use it manually.
If you have already tried this, or you go through the manual steps and it still will not focus, then there may well be a fault with the camera.
Hope this helps,
Simon
