Multifocal lenses have been a great blessing to many of us. However, when obstacles at ground level are viewed with these glasses, blurring and depth perception problems can occur. Researchers from New Zealand tested 30 community dwelling individuals while walking with multifocal glasses and with single-lens glasses.
Study subjects were asked to walk a 15 meter (50 ft) walkway where they had to step over foam-block obstacles placed randomly. When they wore multifocal lenses their pace was significantly slower than when wearing single-lens glasses. They then walked the same walkway while reading letters at eye-level posted at the end. During this dual task they contacted the objects much more frequently than when wearing multi-focal lenses.
PositiveTip: Older people might be better off considering single-lens glasses to help prevent falls.