Based on the scalar diffraction theory and the boundary condition of Rayleigh-Sommerfeld, the accurate on-axis propagating wave function of plane wave diffracted by small circular band is obtained by solving the first integral of Rayleigh-Sommerfeld.

• 摘要从标量衍射理论出发，采用瑞利－索末菲衍射边界条件，通过求解第一类瑞利－索末菲衍射积分得到平面波经圆环衍射后轴上的波函数，进而分析轴上的光强特性以及光强极值数量、位置和大小与衍射圆环内外孔径的关系。