[转载]FRED运用：Arizona眼睛模型 [复制链接]

简介 SYgkYR  
人眼光学模型可用来设计眼科用设备，光学系统注定了要与人眼一起使用。本文演示了这样一个模型：Arizona眼睛模型，在Jim Schwiegerling教授的书中有详细描述：《Field Guide to Visual and Ophthalmic Optics》。AZ眼睛模型达到了基于平均临床数据所决定的轴上和轴外像差等级。FRED文件包含了此眼睛模型及几个用来分析它的光源，并包括一个基于想要的屈光度来调整模型的内嵌脚本。 m
wF{z.t"  
f
~f)6XU|  
模型 AzSmfEaU0  
?p>m;Aq  
模型的定义如表1种所示，由半径、圆锥常数、折射率、阿贝数、到下一面的距离等一系列表面组成。一些参数由屈光度（A）来决定。 c(s: f@ 1  
H9[0-Ur5  
<qBM+m$|)  
在FRED中使用0屈光度来创建的，光瞳加在了透镜的前面。材料是创建一个新的材料并选择类型“Model Material”,输入的参数是nd和vd. h<g2aL21?F  
gdg "g6b  
光源 M|UCV_omN  
t~Qj$:\  
多个光源定义来分析该模型的不同特性。图1显示了所以的光源和提示信息告诉您他们可以用来做什么。 Rvd'uIJ  
4?c0rC<  
Po\d!  
QGnUPiD
^  
除了“Letter F”之外的所有光源的光线位置设定在了孔径光阑位置处，并增加了pre-propagation distance= -8。尽管光线在光瞳处创建，规定的传输方向相对于光线位置在pre-propagation distance之后。这意味着光束沿着Z轴在眼睛的前面以平行光入射，而不是在光瞳处入射。 {^R>H|~  
I-W,C&J>  
在往下看是内置的脚本用来修改屈光度，使其为4（250mm），光源“Letter F”在视网膜处生成一个字母为F的图像。绿色的光线聚焦的非常好而红色和蓝色光线有一点的模糊。使用Positions Spot Diagram分析工具来观察最为合适。 {wf5HA  
<}}u'5;^?x  
HgTBON(  
m-Qy6"eW  
视网膜的散射 )~ ^`[`  
pwA~?$B1  
在散射文件中，有一个名为“Retina surface”的72%的反射型朗伯散射，它为视网膜的散射提供了一个粗略的近似。为了模拟来自视网膜的散射，改变自定义元件“Eye ball” 下的视网膜的表面从“halt all” 到”Allow All”。并使几何中“plane”可追迹。 ]#W9l\  
$NBQv6#:  
CxrsP.  
##s:Ww  
注意在视网膜的表面有散射重点采样规格定义，在“Scatter”标签的底部可获取该信息。“toward pupil”指定散射光朝向光瞳，半角度10度。 V%voe  
3.h0  
>oapw5~5  
|)[&V3+|  
脚本 %kuUQ%W1  
;Ao`yC2(v  
内置脚本使用对话框显示屈光度和光瞳直径的数值设置。使用FRED Basic脚本创建和使用对话框非常容易。图6显示了如何获取用户自定义对话框，如下图所示： 2|${2u`$&y  
5 axt\  
VwT&A9&{8  
9T<k|b[6  
如果“OK”按钮按下，将会核对对话框下面的代码行，如果点击取消则脚本终止。然后输入的参数赋予变量，如果此处是保留为空白，则使用默认值。因此，如果没有值输入并点击“OK”按钮，则脚本是以屈光度为0，光瞳直径为4mm来运行的。 pV$A?b"?*  
余下的脚本计算与屈光度有关的所有参数。 RG_
6& A  
VL$?vI'  
分析 Z OqD.=O(  
!j9(%,PR  
屈光度为4，光瞳直径为4mm，字母F点在视网膜上所成的像。 N({-&A.N  
Nh^q&[?  
A$l  
脚本代码 yp<)v(8|'  
ob9=/ R?i  
Option Explicit     'Remove this to enable non-dimensioned variables to be used. ;7(vqm<V2~  
[=>[2Ty  
Dim entity As T_ENTITY UGP&&A#T-  
Dim op As T_OPERATION 07>D G#  
Dim mat As T_MODELMATERIAL "j=E8Dd}  
Dim A As Double CT(HTu  
Dim pupilDiam As Double |wyua@2  
Dim eID As Long w^[:wzF0  
Dim parID As Long sc z8`%  
Dim count As Integer A%~t[
H  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double 5qkyi]/U8  
Dim tlens As Double, nlens As Double *nwH1FjH  
Dim curv As Double, conic As Double gj82qy\:  
Dim ok As Long ;6`7 \  
nQG<OVRClS  
Sub Main a@#<qf8g  
)#,a'~w  
    '用户输入对话框 f+2mX"Z[F  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 ~l*[=0}  
        TextBox 220,21,40,21,.TextBox1 'default: 0 r|ogF8YN  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 5[P^O6'  
        OKButton 40,91,90,21 h@Ix9!?+  
        CancelButton 190,91,90,21 Or-LQ^~  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 AA}+37@2I  
        TextBox 220,49,40,21,.TextBox2 'default: 4 X|y0pH:S  
    End Dialog _$KkSMA~_  
    Dim dlg As UserDialog ZpZoOdjslV  
iN2591S  
    ok = Dialog (dlg) x#t?`  
(mx}6A  
    If ok=0 Then    'cancel button was pressed )9+H[  
        Print "Execution cancelled." +B4i,]lCx  
        End T^Hq 5Oy  
    End If 0kaMYV?  
3vEwui-5  
    'Assign accommodation and pupil diameter & use defaults if field left empty 4r9AUmJqw  
    If dlg.TextBox1 = "" Then ngzQVaB9  
        A = 0           'Default accommodation `-5gsJ  
    Else ~jJe|zg>  
        A = CDbl(dlg.TextBox1) 0VIR=Pbp  
    End If tNxKpA |F  
TtgsM}Fm  
    If dlg.TextBox2 = "" Then ;s5JYR  
        pupilDiam = 4   'Default pupil diameter f_IsY+@  
    Else h-\+# .YP  
        pupilDiam = CDbl(dlg.TextBox2) D+7[2$:z  
    End If hjp,v)#  
wLo<gA6;  
    Print " " vh^?M#\  
    Print "Accommodation = " & A & " Diopters" x'V:qv*O  
    Print "Pupil Diameter = " & pupilDiam & " mm" Jv~^hN2  
>FL%H=]  
    ' Calculate new parameters with accommodation !)FKF7'  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness 2D"aAI<P  
ephvvj~zW4  
    Rant = 12.0 - 0.4*A                     'Radius of anterior lens `bZgw  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens (1%A@4  
HcHwvf6y  
    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens r^,"OM]  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens JC7:0A^  
8B6-f:  
    tlens = 3.767 + 0.04*A                  'Lens thickness ?qb
q\t  
*Q;?p
hr  
    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction 2QKt.a  
l2kUa'O-  
    'Adjust parameters to account for accommodation |zOwC9-6  
`|4k>5k  
    '************************************************************************* 6e"Lod_ L  
    'Aqueous thickness (Position of Lens) (ZQ?1Qxo  
    '************************************************************************* iO}KERfU  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) Uq.hCb`:  
    GetCustomElement eID, entity VhU,("&pm  
_B
G7JvI  
    parID = FindFullName( "Geometry.Arizona Eye" ) seZb;0  
^(7Qz&q  
    ' Delete any shift(s) in z Zl?9ibm;@  
    count = 0 !'a <Dw5  
    While GetOperationCount(eID)>count ym2"D?P (  
        GetOperation eID, count, op 0Q[;{}W}  
        If op.Type="ShiftZ" Then ]qiX"<s>~C  
            DeleteOperation eID,count i~rb-~o  
            count=count-1 p+${_w>pl{  
        End If gN[^ ,u  
        count=count+1 >*$Xbj*  
    Wend p,7?rI\N  
V2$M`|E  
    'Set new shift in WLCr~r^  
    op.Type = "ShiftZ" G'{&*]Z\:  
    op.val1 = taq 4TSkm`iR  
    op.parent = parID DDZnNSo<JQ  
    AddOperation eID, op l6.&<0pLT  
    Print "Set aqueous humor thickness = " & taq-0.55 ,vuC0
{C^  
UtHloq
(r  
    '************************************************************************* >C`#4e?}  
    'Radius and conic constant of anterior lens x::d}PP7  
    '************************************************************************* gq~"Z[T  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) v(P <_}G  
    GetConic eID, entity, curv, conic _Zxo<}w}y  
}Zfi/^0U  
    SetConic eID, entity, 1/Rant, CCant *O7PH1G  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant 'Qg.D88  
?h,.1Tb  
    '************************************************************************* -:Bgp*S  
    'Radius and conic constant of posterior lens d"thM  
    '************************************************************************* j? Vs"d|  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) 9G4os!x)  
    GetConic eID, entity, curv, conic IaO*{1re  
WnA Y<hZ|  
    SetConic eID, entity, 1/Rpost, CCpost Yh{5O3(;  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost M*aYcIU((  
w7f)v\p  
    '************************************************************************* dcfwUjp[  
    'Lens thickness (Position of posterior lens surface) N[N4!k )!$  
    '************************************************************************* :bXTV?#0  
nIqF:6/  
    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) [C@Ro,mI  
HstL'{&,-m  
    ' Delete any z-shift(s) GK#D R/OM  
    count = 0 -jVg{f!  
    While GetOperationCount(eID)>count 38%"#T3#  
        GetOperation eID, count, op n2Q?sV;m  
        If op.Type="ShiftZ" Then Bk5ft4v-  
            DeleteOperation eID,count upFe{M@  
            count=count-1 \!*F:v0g^  
        End If ,_K:DSiB  
        count=count+1 zbfe=J4c  
    Wend \\35} 9  
/bmkt@$-0  
    'Set new z-shift }d@;]cps  
    op.Type = "ShiftZ" ri4:w_/{,Y  
    op.val1 = tlens OXZx!h  
    op.parent = parID #hXuGBZEI  
    AddOperation eID, op M{p9b E[j  
    Print "Set lens thickness = " & tlens ;HiaX<O!  
r>
G||/Z  
    '************************************************************************* BL%3[JQ  
    'Lens index of refraction zR?1iV.]  
    '*************************************************************************  _w FK+>  
    eID = FindMaterial( "Lens" ) >E WK cocM  
    GetModelMaterial eID, mat ${`q
!  
7<k@{xI/  
    mat.Nd = nlens Yx](3w ID  
    SetModelMaterial eID, mat eQIS`T  
    Print "Set lens index of refraction = " & nlens [5Zi\'~UH)  
kqGydGh*"  
    '************************************************************************* 0\+$j5;  
    'Pupil diameter A@reIt  
    '************************************************************************* _,w*Rv5=  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) ozA%u,\7k  
!k#N] 9D3  
    'Adjust pupil diameter (trimming volume inner hole) }{v0}-~@  
Z 2lX^z  
    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" ^b*ub(5Ot  
nyOvB#f  
    ' Adjust pupil location to just in front of the lens m3|l-[!OA"  
    parID = FindFullName( "Geometry.Arizona Eye" ) HN<e)E38  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) ~!_UDD  
    count = 0 .[Ny(X/]/}  
    While GetOperationCount(eID)>count <<H'Z  
        GetOperation eID, count, op <lWBhrz  
        If op.Type="ShiftZ" Then '@"A{mrE  
            DeleteOperation eID,count fmFs  
            count=count-1 h9rrkV9  
        End If M*dou_Q  
        count=count+1 9W j9=  
    Wend Sf t,$  
    op.Type = "ShiftZ" (AHTv8  
    op.val1 = taq-0.01 uFaT~ 4  
    op.parent = parID l!IN#|{(  
    AddOperation eID, op P+,YWp  
nDNK}O~'  
    Print "Set pupil diameter = " & pupilDiam >,f5 5  
e(9K.3@{  
    'Update AZ Eye subassembly Description G ahY+$L,  
    eID = FindFullName( "Geometry.Arizona Eye" ) q4Y'yp`?K;  
    GetEntity eID, entity $-
gRD|oY  
    entity.Description = "Accommodation = " & A & "D" ?y^ ix+M  
    SetEntity eID, entity 7QaZ|\c  
z@2nre  
    Update ;\iu*1>Z,&  
    Print "DONE!" 8vUq8[[  
     &p=(0$0&-  
End Sub :oJ!9\5  
bWzUWLa  
如果屈光度是4，光瞳直径是4，则会输出如下数据： ShOB"
J-  
o|V=3y Ok  
Accommodation = 4 Diopters ;$UB@)7%  
Pupil Diameter = 4 mm {tnhP^C3>  
Set aqueous humor thickness = 2.81 Rtai?  
Set anterior lens radius = 10.4 and conic constant = -2.375869 mm N$\2  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 +b{tk=Q:  
Set lens thickness = 3.927 `>`{DEDx{5  
Set lens index of refraction = 1.42672 5NMju!/  
Set pupil diameter = 4 "mcuF]7F  
DONE! d^`n/"Ice  
xic&m5j m