[转载]FRED运用：Arizona眼睛模型 [复制链接]

简介 s-Gd{=%/q  
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。 <`SA>P  
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模型 OCdX'HN5Y  
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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。 igTs[q=Ak  
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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. .{t5_,P  
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光源 nnRb  
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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。 }KUK|p5  
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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。 X=?9-z] QO  
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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。 *N
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视网膜的散射 S3HyB b  
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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。 eW<NDI&b  
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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。 I+Yq",{%  
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脚本 \kI{#
 
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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： $rQ7"w J  
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如果“OK”按钮按下，将会核对对话框下面的代码行，如果点击取消则脚本终止。然后输入的参数赋予变量，如果此处是保留为空白，则使用默认值。因此，如果没有值输入并点击“OK”按钮，则脚本是以屈光度为0，光瞳直径为4mm来运行的。 \L?A4Qx)_  
余下的脚本计算与屈光度有关的所有参数。 )j}#6r   
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分析 EUrIh2.Z  
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屈光度为4，光瞳直径为4mm，字母F点在视网膜上所成的像。 iSOyp\E|  
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脚本代码 _I,GH{lhI  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. TntTR"6aD  
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Dim entity As T_ENTITY 9RSviIi$  
Dim op As T_OPERATION >ZgV8X:  
Dim mat As T_MODELMATERIAL eq"Xwq*  
Dim A As Double T#Bj5
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Dim pupilDiam As Double gCRPaF6  
Dim eID As Long iM1E**WCtv  
Dim parID As Long 805oV(-  
Dim count As Integer &>Z;>6J,  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double hZo  f  
Dim tlens As Double, nlens As Double e`JWY9%  
Dim curv As Double, conic As Double ~-sG&u>  
Dim ok As Long p,(W?.ZDN?  
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Sub Main 5K&A2zC|  
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    '用户输入对话框 [T[]U  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 fX\y/C  
        TextBox 220,21,40,21,.TextBox1 'default: 0 Dequ'  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 eQ[}ALIq  
        OKButton 40,91,90,21 
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        CancelButton 190,91,90,21 tblduiN   
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 V4n;N  
        TextBox 220,49,40,21,.TextBox2 'default: 4 n8\88d  
    End Dialog )@tHS-Jf  
    Dim dlg As UserDialog Ui1s
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    ok = Dialog (dlg) r1=j$G  
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    If ok=0 Then    'cancel button was pressed j]-_kjt  
        Print "Execution cancelled." pnL[FMc  
        End '<e$ c  
    End If !N][W#:  
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    'Assign accommodation and pupil diameter & use defaults if field left empty S|6i]/  
    If dlg.TextBox1 = "" Then R7h3O0@!  
        A = 0           'Default accommodation z/WGL  
    Else u35"oLV6}#  
        A = CDbl(dlg.TextBox1) H_| re  
    End If &U([Wd?E2  
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    If dlg.TextBox2 = "" Then /m^G 99N  
        pupilDiam = 4   'Default pupil diameter >b:5&s\9  
    Else c7[Ba\Cr4h  
        pupilDiam = CDbl(dlg.TextBox2) *<"{(sAvk  
    End If eZhF<<Y  
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    Print " " i]@k'2N  
    Print "Accommodation = " & A & " Diopters" JnqP`kYbTE  
    Print "Pupil Diameter = " & pupilDiam & " mm" :>H{?  

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    ' Calculate new parameters with accommodation !HhF*Rlr  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness \PG_i'R  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens 0;OZ|;Z  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens E]a;Ydf~  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens @~5Fcfmm  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens $S2 /*  
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    tlens = 3.767 + 0.04*A                  'Lens thickness Ul 85-p  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction w?M"`O(  
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    'Adjust parameters to account for accommodation @LS%uqs  
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    '************************************************************************* 0=40}n&`  
    'Aqueous thickness (Position of Lens) kK:Wr&X0H  
    '************************************************************************* mjk<FXW  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) ip*^eS^  
    GetCustomElement eID, entity W?ghG  
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    parID = FindFullName( "Geometry.Arizona Eye" ) `JGW8
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    ' Delete any shift(s) in z ^4Se=Hr z2  
    count = 0 $DnR[V}rR!  
    While GetOperationCount(eID)>count $?[pcgv  
        GetOperation eID, count, op nhZ/^`Y<  
        If op.Type="ShiftZ" Then ,KPrUM}  
            DeleteOperation eID,count _t4(H))]vG  
            count=count-1 ;l < amB  
        End If 7,uD7R_  
        count=count+1 CU*;>h1~u  
    Wend ]'hel#L;l  
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    'Set new shift in ^6Yt2Bhs  
    op.Type = "ShiftZ" YOvhMi  
    op.val1 = taq +<B"g{dLuX  
    op.parent = parID R4DfqX  
    AddOperation eID, op A\E ))b9+  
    Print "Set aqueous humor thickness = " & taq-0.55 ;Cty"H,  
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    '************************************************************************* ]j$(so"  
    'Radius and conic constant of anterior lens j*GS')Cm  
    '************************************************************************* wCj)@3F  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) A ;|P
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    GetConic eID, entity, curv, conic 9gIim
 
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    SetConic eID, entity, 1/Rant, CCant oBo |eRIt|  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant K]dR%j  
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    '************************************************************************* T+%P+  
    'Radius and conic constant of posterior lens N+pCC  
    '************************************************************************* ]<Q&  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) EEx:Xk%5hX  
    GetConic eID, entity, curv, conic 2l:cP2fa  
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    SetConic eID, entity, 1/Rpost, CCpost K(TejW#  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost p^ OHLT  
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    '************************************************************************* qHd7C3  
    'Lens thickness (Position of posterior lens surface) 3RFU  
    '************************************************************************* axN\ZXU  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) P{StF`>Y  
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    ' Delete any z-shift(s) G6JP3dOT  
    count = 0 f9d{{u  
    While GetOperationCount(eID)>count # |OA>[  
        GetOperation eID, count, op 2{oQ  
        If op.Type="ShiftZ" Then Cyo:Da A  
            DeleteOperation eID,count 6/"#pe^  
            count=count-1 j|XL$Q  
        End If qc'
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        count=count+1 .5 {<bY  
    Wend 1v
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    'Set new z-shift 3`NSSS  
    op.Type = "ShiftZ" WfTl\Dxw  
    op.val1 = tlens z*cKH$':  
    op.parent = parID g+?2@L$L  
    AddOperation eID, op G%K&f1q%  
    Print "Set lens thickness = " & tlens LIyb+rH#yg  
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    '************************************************************************* zp``e;gY  
    'Lens index of refraction t=jG$
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    '************************************************************************* nD!t*P  
    eID = FindMaterial( "Lens" ) <$K7f  
    GetModelMaterial eID, mat 7m:TY>{  
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    mat.Nd = nlens Ies` !W^  
    SetModelMaterial eID, mat ^7=h%{>=  
    Print "Set lens index of refraction = " & nlens s;sr(34  
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    '************************************************************************* 0E{DO<~  
    'Pupil diameter 8VC%4+.FF  
    '************************************************************************* <vxTfE@>bp  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) &(|Ot`el]v  
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    'Adjust pupil diameter (trimming volume inner hole) ~b4kV)[ q  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" '#Do( U'  
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    ' Adjust pupil location to just in front of the lens 7d+0'3%  
    parID = FindFullName( "Geometry.Arizona Eye" ) FiXqypT_(  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) )XoMOz  
    count = 0 :EH>&vm  
    While GetOperationCount(eID)>count C@pn4[jTl  
        GetOperation eID, count, op b%d,X-3  
        If op.Type="ShiftZ" Then oE0~F|(\1  
            DeleteOperation eID,count @iB
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            count=count-1 %:OX^^i;  
        End If d\8j!F^=  
        count=count+1 a=6@} l1<  
    Wend _!w69>Nj  
    op.Type = "ShiftZ" V`1x!
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    op.val1 = taq-0.01 w>'3}o(nY  
    op.parent = parID +HgyM0LFg  
    AddOperation eID, op ;3%Y@FS@  
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    Print "Set pupil diameter = " & pupilDiam p=|S%  
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    'Update AZ Eye subassembly Description :Smyk.B2!  
    eID = FindFullName( "Geometry.Arizona Eye" ) U_Q;WPJ  
    GetEntity eID, entity m9\~dD  
    entity.Description = "Accommodation = " & A & "D" @3~Wukc  
    SetEntity eID, entity ~~Rq
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    Update 0w vAtK|Q  
    Print "DONE!" 7`^=Ie%(K  
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End Sub !\'HKk~V  
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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： aN!,\D  
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Accommodation = 4 Diopters 9hJ  a K  
Pupil Diameter = 4 mm =F5zU5`i  
Set aqueous humor thickness = 2.81 /_yAd,^-+  
Set anterior lens radius = 10.4 and conic constant = -2.375869 ,|j\x  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 S,a:H*Hf  
Set lens thickness = 3.927 8m#y>`  
Set lens index of refraction = 1.42672 90ov[|MkM  
Set pupil diameter = 4 }%^3  
DONE! ^),;`YXZ  
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