Nokia Conversations blog tells about a new downloadable application available for Lumia 920-series and 1020 camera phones - Refocus. The application essentially emulates the post-capture refocus capability available in Lytro and Pelican Imaging cameras:
"Once you have the closest object in focus, tapping the screen on your Lumia will start the capture process – which only takes a couple of seconds (try to be very still). During this time, Nokia Refocus performs a ‘focus sweep’ and creates a depth map.
This new way of taking photos is a great example of computational photography. We’ve now got the ability to change a photo once it’s taken and have a photo that simply couldn’t have been taken by a traditional camera.
The result is a series of 2-8 images, depending on what’s in view, each at five megapixels at a different focus that’ll be aligned and forged together to make one image.
By tapping on any part of this final image you’ll be able to shift the focus to that particular part. The great thing here is that you can achieve a variety of different shots from just the one photo."
Refocus app can also put the whole scene into focus at the same time to provide extra clarity:
Engadget says that Refocus is based on Scalado technology that Nokia acquired a year ago.