[转载]FRED运用：Arizona眼睛模型 [复制链接]

简介 I:iMRvp  
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。 W6i{yneW  
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模型 =oSd M2  
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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。 N$]er'`  
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在FRED中使用0屈光度来创建的，光瞳加在了透镜的前面。材料是创建一个新的材料并选择类型“Model Material”,输入的参数是nd和vd. kJ FWk  
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光源  SW#/;|m  
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多个光源定义来分析该模型的不同特性。图1显示了所以的光源和提示信息告诉您他们可以用来做什么。 {m>ylE  
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除了“Letter F”之外的所有光源的光线位置设定在了孔径光阑位置处，并增加了pre-propagation distance= -8。尽管光线在光瞳处创建，规定的传输方向相对于光线位置在pre-propagation distance之后。这意味着光束沿着Z轴在眼睛的前面以平行光入射，而不是在光瞳处入射。 e9KD mX_  
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在往下看是内置的脚本用来修改屈光度，使其为4（250mm），光源“Letter F”在视网膜处生成一个字母为F的图像。绿色的光线聚焦的非常好而红色和蓝色光线有一点的模糊。使用Positions Spot Diagram分析工具来观察最为合适。 K'r;#I|"J  
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视网膜的散射 k(dakFaC^  
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在散射文件中，有一个名为“Retina surface”的72%的反射型朗伯散射，它为视网膜的散射提供了一个粗略的近似。为了模拟来自视网膜的散射，改变自定义元件“Eye ball” 下的视网膜的表面从“halt all” 到”Allow All”。并使几何中“plane”可追迹。 ~/`/r%1/J  
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注意在视网膜的表面有散射重点采样规格定义，在“Scatter”标签的底部可获取该信息。“toward pupil”指定散射光朝向光瞳，半角度10度。 yKV{V?h?  
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脚本 (CxA5u1|l  
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内置脚本使用对话框显示屈光度和光瞳直径的数值设置。使用FRED Basic脚本创建和使用对话框非常容易。图6显示了如何获取用户自定义对话框，如下图所示： T(7`$<TQ  
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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。 !lgL=Ys(  
余下的脚本计算与屈光度有关的所有参数。 JkAM:,^(  
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分析 ! dzgi:  
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屈光度为4，光瞳直径为4mm，字母F点在视网膜上所成的像。 .r<aPy$  
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脚本代码 2H|:/y  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. (G"'Fb6d  
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Dim entity As T_ENTITY =#G 2}8mQD  
Dim op As T_OPERATION r.H`3m.0q  
Dim mat As T_MODELMATERIAL yV{B,T`W  
Dim A As Double c1'@_Is  
Dim pupilDiam As Double l'+3 6  
Dim eID As Long [MTd<@  
Dim parID As Long %F>~2g?$  
Dim count As Integer ;?2)[a  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double 6ZQ |L=Ytp  
Dim tlens As Double, nlens As Double fc9;
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Dim curv As Double, conic As Double O^@8Drg
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Dim ok As Long p'/\eBhG]=  
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Sub Main C Bkoky9&  
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    '用户输入对话框 5CkG^9  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 .{1$;K @  
        TextBox 220,21,40,21,.TextBox1 'default: 0 @YI{E*?S  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 b{
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        OKButton 40,91,90,21 ZLkl:'E_  
        CancelButton 190,91,90,21 *r`=hNr  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 QHk\Z  
        TextBox 220,49,40,21,.TextBox2 'default: 4 
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    End Dialog Bs~~C8+  
    Dim dlg As UserDialog OsgPNy0  
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    ok = Dialog (dlg) <&5z0rDKWw  
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    If ok=0 Then    'cancel button was pressed G$<(>"Yr~$  
        Print "Execution cancelled." >f]/VaMH{  
        End AjVC{\Ik  
    End If CY1WT  
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    'Assign accommodation and pupil diameter & use defaults if field left empty %6m/ve  
    If dlg.TextBox1 = "" Then Mg2+H+C~:  
        A = 0           'Default accommodation |p|Zv H  
    Else boo361L  
        A = CDbl(dlg.TextBox1) eHphM;C  
    End If D#g-mqar:  
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    If dlg.TextBox2 = "" Then U%q)T61  
        pupilDiam = 4   'Default pupil diameter #dauXUKH  
    Else wNf:_^|}  
        pupilDiam = CDbl(dlg.TextBox2) \]ib%,:YU  
    End If 4>gfLK\R:  
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    Print " " ^)AECn  
    Print "Accommodation = " & A & " Diopters" [?]N GTr#  
    Print "Pupil Diameter = " & pupilDiam & " mm" ;wv[';
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    ' Calculate new parameters with accommodation |9E:S  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness 'oa.-g5  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens PUdv1__C  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens ng1E'c]0@  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens q*hn5K*  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens H,7='n7"  
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    tlens = 3.767 + 0.04*A                  'Lens thickness Vk
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction i).%GMv*r  
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    'Adjust parameters to account for accommodation X`8<;l  
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    '************************************************************************* XcJ5KTn  
    'Aqueous thickness (Position of Lens) N63?4'_W  
    '************************************************************************* #VQZ"7nI@  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) A4j,]hOD  
    GetCustomElement eID, entity SoIK<*J  
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    parID = FindFullName( "Geometry.Arizona Eye" ) Jf^3nBZ  
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    ' Delete any shift(s) in z wT@Z|.)  
    count = 0 x;mw?B[  
    While GetOperationCount(eID)>count yFE0a"0y  
        GetOperation eID, count, op $(1t~u<17  
        If op.Type="ShiftZ" Then $Itmm/M  
            DeleteOperation eID,count Tuvs}  
            count=count-1 7K"3[.  
        End If }e7Rpgu  
        count=count+1 (Jq m9  
    Wend L$ T2 bul  
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    'Set new shift in RXXHg  
    op.Type = "ShiftZ" 4 ]oe`yx  
    op.val1 = taq X@~/.H5  
    op.parent = parID Y.m1d?H 1  
    AddOperation eID, op frcAXh9  
    Print "Set aqueous humor thickness = " & taq-0.55 |~9jO/&r  
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    '************************************************************************* M+t)#O4  
    'Radius and conic constant of anterior lens ?q!4REM  
    '************************************************************************* `I7s|9-=  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) Au2^ T1F  
    GetConic eID, entity, curv, conic dsIbr"m  
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    SetConic eID, entity, 1/Rant, CCant ` nX,x-UM  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant iwnGWGcuS  
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    '************************************************************************* ~}OaX+!  
    'Radius and conic constant of posterior lens w
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    '************************************************************************* ! fk W;|  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) zC*FeqFL<  
    GetConic eID, entity, curv, conic 8GkWo8rPk  
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    SetConic eID, entity, 1/Rpost, CCpost lBP?7`U  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost v&:[?<6-  
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    '************************************************************************* or-k~1D  
    'Lens thickness (Position of posterior lens surface) zlLZ8b+  
    '************************************************************************* 0+mR y57  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) ;(K/O?nrJ  
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    ' Delete any z-shift(s) TTG=7x:3  
    count = 0 F-kjv\  
    While GetOperationCount(eID)>count -~z@W3\  
        GetOperation eID, count, op 7sVM[lr<  
        If op.Type="ShiftZ" Then 1F.._5_"]  
            DeleteOperation eID,count kR+}7G+  
            count=count-1 z,;XWv?  
        End If 'e:4  
        count=count+1 }w)}=WmD  
    Wend KXMf2)pa  
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    'Set new z-shift L#`X ]E  
    op.Type = "ShiftZ" @<DRFP  
    op.val1 = tlens +.djC
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    op.parent = parID Bc!<!  
    AddOperation eID, op H[w';u[%  
    Print "Set lens thickness = " & tlens D <~UaHfk  
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    '************************************************************************* :X":>M;;+  
    'Lens index of refraction a@g <cl7a,  
    '*************************************************************************  XY)X-K$  
    eID = FindMaterial( "Lens" ) xkf2;  
    GetModelMaterial eID, mat HnPy";{  
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    mat.Nd = nlens XK~HfA?  
    SetModelMaterial eID, mat rFcz0  
    Print "Set lens index of refraction = " & nlens ttr`  
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    '************************************************************************* 3]S_w[Q4  
    'Pupil diameter [Zdrm:=]L  
    '************************************************************************* @oY+b!L  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) 86LE )z  
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    'Adjust pupil diameter (trimming volume inner hole) -[!t=qi  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" ]U@~vA#''  
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    ' Adjust pupil location to just in front of the lens YuuTLX%3  
    parID = FindFullName( "Geometry.Arizona Eye" ) #^9bBF/  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) iB99.,o-&  
    count = 0 g mWwlkf9  
    While GetOperationCount(eID)>count 3'p1m`8  
        GetOperation eID, count, op C}
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        If op.Type="ShiftZ" Then !Th5x2  
            DeleteOperation eID,count zWPX  
            count=count-1 ,g'>
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        End If ,J2qLH1  
        count=count+1 [PXq<ST  
    Wend xA^E+f:W_  
    op.Type = "ShiftZ" 8@ f!,!Wn  
    op.val1 = taq-0.01 7"Nd
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    op.parent = parID C-ORI}o  
    AddOperation eID, op d@^%fVhG  
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    Print "Set pupil diameter = " & pupilDiam l4mRNYv)z  
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    'Update AZ Eye subassembly Description +*Wlj8  
    eID = FindFullName( "Geometry.Arizona Eye" ) ;4dFL\KU  
    GetEntity eID, entity kE6/
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    entity.Description = "Accommodation = " & A & "D" ;d>n2  
    SetEntity eID, entity ,^n&Q'p3  
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    Update >aVtYp B  
    Print "DONE!" ";Cf@}i>  
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End Sub a/s5Oit2'X  
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如果屈光度是4，光瞳直径是4，则会输出如下数据： D HQxu4  
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Accommodation = 4 Diopters ?zP 2   
Pupil Diameter = 4 mm s[eSPSFZ  
Set aqueous humor thickness = 2.81 vC1fKo\p  
Set anterior lens radius = 10.4 and conic constant = -2.375869 QSzht$8  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 h$sOJs~6h  
Set lens thickness = 3.927 mc`Z;D/mt  
Set lens index of refraction = 1.42672 ;`xCfOY(  
Set pupil diameter = 4 =!DX,S7  
DONE!  mVS^HQ:  
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