MESH - EX17 - Dielectric lens modelled with GO

关于范例17的切 MESH，大家来研究一下gl0 ，看他为何要这样做?
Project name: Dielectric lens modelled with GO (Geometrical Optics)
Description: A dielectric lens with a spherical surface (S1) and elliptical surface (S2) is constructed. The lens is illuminated with a radiation pattern point source and the far field pattern is computed. The lens is modelled with the dielectric geometrical optics approximation.
Lens user parameters:
Frequency:            freq = 30e9
Diameter:            D = 10 lambda
Focal length:            F = 1.5 D
Relative permitivity:        epsr = 6愡tand = 0.005
Work in mm:            sc = 1e-3
Derived variables:
Wavelength:            lam = c0/freq/sc
Refraction index:        n = sqrt(epsr)
Lens thickness:            T = (2*F - sqrt(4*F^2 - D^2))/(2*(n-1))
Ellipse offset distance:        v0 = (F + T)/(n + 1)
Ellipse minor axis length:        u0 = sqrt(n^2 - 1)*v0
Ellipse major axis length:        n*v0
Included angle to edge of lens:    alpha = arcsin(D/(2*F))
Arclength to edge of lens:    arclength = alpha*F
Mesh variable:            gL0 = arclength/10

这个东东我也想学学
准备算个玩玩........

什么切mesh,你的文章里只给出了变量的设置呀?

Please see the image and check these variables.

补充一下这是透镜天线  lens antenna
　　在振子或喇叭形辐射器前装有透镜，从而使辐射能量集中成窄的射束的微波天线（见图）。透镜是一种能通过电磁波而其折射系数不等于 1的三维结构。点源或线源发出的球面波或柱面波经过透镜可以变换成平面波，从而得到笔形或扇形波束。透镜的折射系数可能是位置的函数，透镜的形状决定其口面场分布。
透镜可以用折射系数n大于1的自然介质制成，也可以是由金属栅网或金属片等组成的人工介质结构（n＞1或n＜1）。n＝c/vφ(式中c为光速;vφ为介质中的相速)，n大于1的透镜称为减速透镜，n小于1的透镜称为加速透镜。当透镜正反两面都是折射面时，则称为双面透镜，当只有照射面是折射面时，则称为单面透镜。