apple has bought linx in a deal worth around $ 20 million -lrb- £ 13.5 million -rrb- .
tech giant has confirmed the acquisition but not revealed any more details .
linx makes ` multi-aperture ' cameras small enough to fit into phones .
rather than capturing a flat 2d image , the technology is able to sense the depth of each object in a photograph and lets people refocus the shot .