我在看zemax自定义面型的程序时，光线追迹的地方看不太懂，就是看不懂程序上面表达的意思是什么。
主要是下面的两段程序（下面的两段程序为平面衍射光栅的程序中的一部分）：
这两段程序，case4部分我看了几个面型的程序都是一模一样的，虽然不太理解，但应该照搬就可以了；case5部分每个面型对应不一样，这块理解不了。两部分里面的参数的意义，对应有.h文件里面有具体解释，我放在附件里面。同时附件我也放一个平面衍射光栅的和一般球面镜的完成程序，你参考下。
case 4:
/*ZEMAX wants a paraxial ray trace to this surface */
/* x, y, z, and the optical path areunaffected, at least for this surface type */
/* for paraxial ray tracing, the returnz coordinate should always be zero. */
/* paraxial surfaces are always planeswith the following normals */
/* for paraxial ray tracing,grating effects are ignored */
/* this is exactly like the standardsurface code */
UD->ln = 0.0;
UD->mn = 0.0;
UD->nn = -1.0;
power = (FD->n2 -FD->n1)*FD->cv;
if ((UD->n)!= 0.0)
{
(UD->l) = (UD->l)/(UD->n);
(UD->m) = (UD->m)/(UD->n);
(UD->l) = (FD->n1*(UD->l)- (UD->x)*power)/(FD->n2);
(UD->m) = (FD->n1*(UD->m)- (UD->y)*power)/(FD->n2);
/* normalize */
(UD->n) = sqrt(1/(1 +(UD->l)*(UD->l) + (UD->m)*(UD->m) ) );
/* de-paraxialize */
(UD->l) = (UD->l)*(UD->n);
(UD->m) = (UD->m)*(UD->n);
}
break;
case 5:
/*ZEMAX wants a real ray trace to this surface */
if (FD->cv == 0.0)
{
UD->ln = 0.0;
UD->mn = 0.0;
UD->nn = -1.0;
if (Refract(FD->n1, FD->n2,&UD->l, &UD->m, &UD->n, UD->ln, UD->mn, UD->nn))return(-FD->surf);
}
else
{
/* okay, not a plane. */
a= (UD->n) * (UD->n) * FD->k + 1;
b = ((UD->n)/FD->cv)- (UD->x) * (UD->l) - (UD->y) * (UD->m);
c = (UD->x) *(UD->x) + (UD->y) * (UD->y);
rad = b * b - a * c;
if (rad < 0)return(FD->surf); /* ray missed thissurface */
if (FD->cv > 0) t =c / (b + sqrt(rad));
else t = c / (b - sqrt(rad));
(UD->x) = (UD->l) *t + (UD->x);
(UD->y) = (UD->m) *t + (UD->y);
(UD->z) = (UD->n) *t + (UD->z);
UD->path = t;
zc = (UD->z) *FD->cv;
rad = zc * FD->k * (zc* (FD->k + 1) - 2) + 1;
casp = FD->cv /sqrt(rad);
UD->ln = (UD->x) *casp;
UD->mn = (UD->y) *casp;
UD->nn = ((UD->z) -((1/FD->cv) - (UD->z) * FD->k)) * casp;
if (Refract(FD->n1, FD->n2, &UD->l, &UD->m,&UD->n, UD->ln, UD->mn, UD->nn)) return(-FD->surf);
}
/* okay, now account for the grating*/
/* the grating affects both therefraction angle and the phase, or OPD, of the ray */
T = FD->param[1];
M = FD->param[2];
L = FD->wavelength;
/* here is the phase &phase change */
/* the ZEMAX convention is we subtractout the positive phase...*/
/* the index of the incident mediummust be divided out because ZEMAX will
multiply in the index to convert pathto optical path! */
UD->path += UD->y*M*T*L /FD->n1;
dpdx = 0.0; /* included hereonly for extension to the general case */
dpdy = M*T*L;
/*
This is a generic vector diffraction routinemore or less from
W. T. Welford, Aberrations of optical systems,Adam Hilger Ltd 1986.
*/
/* account for possible change inindex or mirrors */
dpdy /= fabs(FD->n2);
if (FD->n1*FD->n2 < 0) dpdy =-dpdy;
if (FD->n1 < 0) nn =-1.0;
else nn = 1.0;
nx = -UD->ln;
ny = -UD->mn;
nz = -UD->nn;
ux = UD->l + nn * (dpdx);
uy = UD->m + nn * (dpdy);
uz = UD->n;
rad = nx*ux + ny*uy + nz*uz;
rad = 1.0 - (ux*ux + uy*uy +uz*uz) + rad*rad;
if (rad <= 0.0) rad = 0.0;
else rad = sqrt(rad);
UD->l = ux - (nx*ux + ny*uy+ nz*uz)*nx + nx * rad;
UD->m = uy - (nx*ux + ny*uy+ nz*uz)*ny + ny * rad;
UD->n = uz - (nx*ux + ny*uy+ nz*uz)*nz + nz * rad;
break;
发表于 2016-9-20 09:34
发表于 2016-9-20 13:18
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