高量级光衰减时对线偏振片组衰光系数的研究

利用琼斯矢量法推导实际偏振片的琼斯矩阵和两片偏振片组的透射光强表达式和衰光系数表达式.通过计算说明,在高量级光衰减时用马吕斯定律计算偏振片的衰光率存在一定误差.因此,该衰光系数表达式可作为马吕斯定律实际运用时的修正式.依据该理论推导得出两偏振片组的最大衰光率为2ε2,并得到三偏振片组的关于θ2的透射光强表达式.该式以及相应实验表明在θ1,θ2=90°,135°和90°,315°时最大衰光率可达到2ε4.

Light attenuation coefficient of polarization attenuator at high attenuation level

By use of the Jones vector we deduced the Jones matrix of actual polarizer and light transmission expression,as well as the light attenuation coefficient(LAC)of two polarizers.According to computation,certain error exists when using Malus-Law to calculate polarizer's light attenuation ratio at high attenuation level.So the deduced LAC expression can be considered as a correction to Malus-Law.We get the maximum light attenuation ratio 2ε~2 of two polarizers and light transmission expression about θ_2 of three polarizers.Both the expression and experimental data indicate that the maximum light attenuation ratio can reach 2ε~4 when[θ_1,θ_2]=[90°,135°]or[90°,315°].