LG 42PM4700 Owner's Manual page 192

Warning when using 3D glasses
❐
✎ Do not use the 3D glasses as a replacement for your own corrective glasses,
sunglasses, or protective goggles. Improper use of 3D glasses may cause eye
injuries.
✎ Do not store 3D glasses in extreme conditions. Exposure to excessively high
or low temperatures may deform the lenses. Do not use deformed glasses.
✎ Do not apply pressure to or subject 3D glasses to any impact. Subjecting 3D
glasses to rough handling may cause a defect.
✎ The lenses on 3D glasses are vulnerable to scratching. Use only a soft and
clean cloth for cleaning. A dirty cloth may scratch the lens surface.
✎ Scratching the lens surface of the 3D glasses with sharp objects or cleaning
with chemicals may distort 3D images.