Apple has been granted a patent for technology that could stop smartphone cameras being used at concerts.
The patent describes a smartphone camera receiving coded infrared signals beamed from emitters in public places.
The handset could then offer on-screen information or disable the camera functionality to stop pictures being taken.
One technology journalist said the technology could frustrate consumers.
Image copyright APple/United States Patent and Trademark Office Image caption The patent drawing shows an old version of Apple's smartphone
"It could harm Apple in the eyes of some people," said Stuart Miles, founder of gadget site Pocket Lint.