湖北大学：《大学物理》第十七章（17-7） 衍射光栅

Multiple rays interference Grating diffraction is the combinations of N parallel rays. Any two adjacent parallel rays have a phase difference of Ao The path difference bc between BC=(a+b)sin 0=d sin e Ap= Bd I rays from adjacent slits are

Multiple rays interference I BC = (a +b)sin  = d sin    a b d B C   a b d B C   a b d B C   a b d B C The path difference BC between rays from adjacent slits are:    BC  = 2 Grating diffraction is the combinations of N parallel rays. Any two adjacent parallel rays have a phase difference of 

1) Grating equation光栅方程 principal maxima主明纹 (主最大) BC 3级明纹 Chien atb △qp=2兀 sin e 2 F2级明纹 k=0±1.±2.±3 (a+b)sinO=kk=0±1.±2±3 1级明纹 P中央 Grating equation光栅方程 明纹 >-1级明纹 dt 10 栅钅b 2级明纹 B 屏幕 -3级明纹

1) Grating equation 光栅方程： principal maxima 主明纹 Y I 光 栅 透 镜 屏 幕      2 2 sin BC a + b  = = k = 01. 2.3... k = 01. 2.3...   a b d B C Grating equation 光栅方程 = 2k (a +b)sin  = k 中央 明纹 1级明纹 2级明纹 3级明纹 -1级明纹 -2级明纹 -3级明纹 （主最大）