光學系統的截止頻率計算

數值孔徑 (Numerical Aperture, NA) 計算

Na = \frac {D} {2f}

解析度 (Resolution) 計算

Resolution = \frac {\lambda}{2NA}

截止頻率計算

f_0= \frac {D}{2 \lambda f}

f_0= \frac{1}{\lambda} \frac{D}{2f}

f_0= \frac{NA}{\lambda}

解析度與截止頻率關係

Resolution = \frac{1}{2f_0} = \frac{\lambda}{2NA}