[转载]FRED运用：Arizona眼睛模型 [复制链接]

简介 L9O;K$[s  
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。 Hrpz4E%\Aw  
YIwa =^  
模型 Bc.de&Bxz_  
(=uT*Cb  
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。 P!Fykg  
S[!6Lw  
b5H}0<  
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. ?
:3hp2k<  
}0pp"
[JU  
光源 4_5f4%S  
M>Q ZN  
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。 +Kb 7N, "  
!O%!A<3  
+# 'w} P  
["f6Ern  
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。 W]/J]O6  
o3`U;@&u  
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。 r<fcZ)jt|  
;>mM9^Jaf
 
ya1 aWs~  
:0:Tl/))  
视网膜的散射 ,2$<Pt;  
'UhHcMh:  
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。 QNOdt2NN  
 .x%w#  
i*/i"W<  
KGM__ZO.  
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。 0zNbux_  
2|^@=.4\  
:.ZWYze  
u ,3B[  
脚本 OM0r*<D"!  
Lq5xp<  
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： hUi@T}aA|  
"6\5eFN;  
:wS&3:h  
$,@}%NlHc  
如果“OK”按钮按下，将会核对对话框下面的代码行，如果点击取消则脚本终止。然后输入的参数赋予变量，如果此处是保留为空白，则使用默认值。因此，如果没有值输入并点击“OK”按钮，则脚本是以屈光度为0，光瞳直径为4mm来运行的。 "W"^0To  
余下的脚本计算与屈光度有关的所有参数。 UgAp9$=z  
E;CM"Y*  
分析 uQ-GJI^t  
"jyo'r  
屈光度为4，光瞳直径为4mm，字母F点在视网膜上所成的像。 ]TT >3"Dw7  
't`h?VvL  
y@7fR9hp<  
脚本代码 q  
|&8XmexLb  
Option Explicit     'Remove this to enable non-dimensioned variables to be used. zEFS\nP}E  
nQmHYOF%  
Dim entity As T_ENTITY #4mRMsW5"  
Dim op As T_OPERATION
?)-6~p 4N  
Dim mat As T_MODELMATERIAL ]S4"JcM  
Dim A As Double 3[u- LYW  
Dim pupilDiam As Double **%&|9He  
Dim eID As Long .4\I?  
Dim parID As Long b_RO%L:"yL  
Dim count As Integer BS fmS(.  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double FzX ;~CA  
Dim tlens As Double, nlens As Double IOZw[9](+  
Dim curv As Double, conic As Double 1<'z)r4  
Dim ok As Long GP c B(  
7JBs7L
G  
Sub Main J[:#(c&c!1  
XiTi3vCe  
    '用户输入对话框 zN!W_2W*  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 Hi={(Z5tC4  
        TextBox 220,21,40,21,.TextBox1 'default: 0 LHA^uuBN}  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 T
;(,9>Qsu  
        OKButton 40,91,90,21 B1_9l3RM  
        CancelButton 190,91,90,21 x t-s"
A  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 `15}jTi  
        TextBox 220,49,40,21,.TextBox2 'default: 4 HNS^:XR  
    End Dialog [T_[QU:A  
    Dim dlg As UserDialog }d}gb`Du  
qI9j=4s.  
    ok = Dialog (dlg) G,!jP2S  
>u> E !5O  
    If ok=0 Then    'cancel button was pressed dPu
27 "  
        Print "Execution cancelled." ,nYa+
e  
        End xcw:H&\w6  
    End If uuEvH<1  
CmBPCjh  
    'Assign accommodation and pupil diameter & use defaults if field left empty VYb,Hmm>kC  
    If dlg.TextBox1 = "" Then @`KbzN_h/  
        A = 0           'Default accommodation ^5]9B<i[Y  
    Else ivgX o'=  
        A = CDbl(dlg.TextBox1) 'S6zkwC]  
    End If n)X%&_  
Pr} l y  
    If dlg.TextBox2 = "" Then >P j#?j*Y  
        pupilDiam = 4   'Default pupil diameter 1R8tR#l  
    Else $V3If  
        pupilDiam = CDbl(dlg.TextBox2) A x8>  
    End If 0J'^<GTL  
|.Vgk8oTl  
    Print " " OE(y$+L3_I  
    Print "Accommodation = " & A & " Diopters" @@\qso  
    Print "Pupil Diameter = " & pupilDiam & " mm" }Q:
CZ  
aQ(P#n>a2  
    ' Calculate new parameters with accommodation Se!w(Y&  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness m#BXxS#B<_  
,|RKM  
    Rant = 12.0 - 0.4*A                     'Radius of anterior lens #WG}"[ ,c  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens _qPKdGoM  
@lDnD%vZ`  
    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens |Jx:#OM  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens SYi
!%  
0"e["q{|  
    tlens = 3.767 + 0.04*A                  'Lens thickness MMrN#&r  
k^d]EF  
    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction VvIUAn  
%TI3Eb  
    'Adjust parameters to account for accommodation 'yH  
?cWwt~N9  
    '************************************************************************* mxCneX  
    'Aqueous thickness (Position of Lens) ^E/6vG  
    '************************************************************************* SVVEb6&  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) 8OOAPp$%|  
    GetCustomElement eID, entity 6P@K]jy& n  
A\S=>[ar-  
    parID = FindFullName( "Geometry.Arizona Eye" ) VM5'd  
U0-RG  
    ' Delete any shift(s) in z 4
PD
5i  
    count = 0 <[ dt2)%L>  
    While GetOperationCount(eID)>count '['%b  
        GetOperation eID, count, op ih)\P0wed  
        If op.Type="ShiftZ" Then =,it`8;  
            DeleteOperation eID,count c86?-u')  
            count=count-1 }0<2n~3P  
        End If a=ZVKb  
        count=count+1 O6$,J12l  
    Wend .7 j#F  
7)D[}UXz  
    'Set new shift in RU/WI<O
 
    op.Type = "ShiftZ" O D5qPovsd  
    op.val1 = taq T0fm6 J  
    op.parent = parID 5xKod0bA  
    AddOperation eID, op ^vh!1"T  
    Print "Set aqueous humor thickness = " & taq-0.55 xr.;B`T0\'  
9E5*%Hu_  
    '************************************************************************* [}Xw/@Uc;  
    'Radius and conic constant of anterior lens [H!do$[>  
    '************************************************************************* "PTEt{qn  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) 7~"eT9WV  
    GetConic eID, entity, curv, conic &to~#.qc  
GNHXtu6  
    SetConic eID, entity, 1/Rant, CCant V&j]*)  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant a'HHUii=  
 IN6L2/Q  
    '************************************************************************* 0ie)
$fi  
    'Radius and conic constant of posterior lens p);[;S  
    '************************************************************************* HqqMX`Rof  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) ;K l'[~z  
    GetConic eID, entity, curv, conic w$s6NBF7  
]7,0>  
    SetConic eID, entity, 1/Rpost, CCpost )RFY2}  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost Ot=nKdP}D  
{7X9P<<L7  
    '************************************************************************* ci?\W6  
    'Lens thickness (Position of posterior lens surface) u-.5rH l  
    '************************************************************************* ORX<ZOt1  
?gAwMP(>  
    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) Iw] ylp  
D)4#AI  
    ' Delete any z-shift(s) /w6'tut  
    count = 0 d+h~4'ebv  
    While GetOperationCount(eID)>count  m5J@kE%  
        GetOperation eID, count, op qMVuB
v  
        If op.Type="ShiftZ" Then 3&[d.,/  
            DeleteOperation eID,count 0ZD)(ps|  
            count=count-1 3^H-,b0^  
        End If 9. FXbNYg  
        count=count+1 Ao\OU}  
    Wend ~_CZ1  
j/wQ2"@a  
    'Set new z-shift ou)0tX3j  
    op.Type = "ShiftZ" FS)C<T]t  
    op.val1 = tlens C.u)2[(  
    op.parent = parID UaXIrBc  
    AddOperation eID, op asvM/9  
    Print "Set lens thickness = " & tlens l:~ >P[  
dZkKAK:v  
    '************************************************************************* d@ZXCiA},  
    'Lens index of refraction hE\gXb  
    '************************************************************************* 'g<FL`iP  
    eID = FindMaterial( "Lens" ) ;l `(1Q/  
    GetModelMaterial eID, mat Y2uy@j*N  
jX$U)O  
    mat.Nd = nlens "_rpErm }  
    SetModelMaterial eID, mat 6m(+X MS  
    Print "Set lens index of refraction = " & nlens {^:i}4ZRl  
+
:C
.G[+  
    '************************************************************************* W+V &  
    'Pupil diameter (L1O;~$  
    '************************************************************************* !8 l&%  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" )
B.Z5+MgM  
@v6{U?  
    'Adjust pupil diameter (trimming volume inner hole) >A L^y(G  

;;^?vS  
    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" Y!u">M#@  
T-oUc
uQB  
    ' Adjust pupil location to just in front of the lens ZD?LsD3  
    parID = FindFullName( "Geometry.Arizona Eye" ) >Zm|R|{BE  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) CF_2ez1u0y  
    count = 0
5Yk|  
    While GetOperationCount(eID)>count h5E<wyd96.  
        GetOperation eID, count, op sU^K5oo  
        If op.Type="ShiftZ" Then a\MJh+K  
            DeleteOperation eID,count L6=5]
?B=  
            count=count-1 !r*JGv=  
        End If ))6iVgSE$  
        count=count+1 VRv.H8^{  
    Wend *ES"^N/88  
    op.Type = "ShiftZ" i~DLo3  
    op.val1 = taq-0.01 ,{RWs^W2  
    op.parent = parID `GooSX  
    AddOperation eID, op t/x]vCP,2D  
7c'OIY].,  
    Print "Set pupil diameter = " & pupilDiam ~05(92bK  
}"^d<dvuz  
    'Update AZ Eye subassembly Description #@uF?8u  
    eID = FindFullName( "Geometry.Arizona Eye" ) `C*psS  
    GetEntity eID, entity nhq,Y0YH  
    entity.Description = "Accommodation = " & A & "D" F n*+uk  
    SetEntity eID, entity @7Nc*-SM  
!V0)
eC50  
    Update c#[d7t8ONe  
    Print "DONE!" <3{>;^|e
 
     \z-OJ1[F  
End Sub PtKrks|y  
S#ud<=@!9  
如果屈光度是4，光瞳直径是4，则会输出如下数据： hQJ- ~  
d[e;Fj!  
Accommodation = 4 Diopters ?trqe/  
Pupil Diameter = 4 mm VSc)0eyn  
Set aqueous humor thickness = 2.81 Wl>$<D4mO[  
Set anterior lens radius = 10.4 and conic constant = -2.375869 K./L'Me  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 +,0 :L :a  
Set lens thickness = 3.927 .t%`"C  
Set lens index of refraction = 1.42672 M|'![]-  
Set pupil diameter = 4 ;u?H#\J,  
DONE! 0\Myhh~DLE  
V7Mp<x%