A plane electromagnetic wave, XE e-ot) after passing through an optical element emerges as 2x+3E0 ) (kz-cot) . The optical element is Quarter wave plate whose optical axis making 30 with x-axis. Quarter wave plate whose optical axis making 60 with x-axis. Half wave plate whose optical axis making 30 with x-axis. Half wave plate whose optical axis making 60 with x-axis.