LG 47LA6200 Owner's Manual page 240

Caution❐when❐viewing❐3D❐images
❐ ❐
✎ When viewing 3D images, it is recommended that the viewer maintain a
distance of at least twice the screen's diagonal length.
✎ 3D images may not be viewed correctly with shutter-type glasses that require
recharging.
✎ If a future 3D broadcasting format that is not supported by this TV becomes
the standard, an additional device such as a set-top box may be required.