Samsung UN46ES7500F E-Manual page 265

ΠThe 3D Active Glasses may not work
properly if there is any other 3D
product or electronic devices turned
on near the glasses or TV. If there
is a problem, keep other electronic
devices as far away as possible from
the 3D Active Glasses.
ΠBe sure to stay within the viewing
angle and optimum TV viewing
distance when watching 3D pictures.
Otherwise, you may not be able to