[转载]FRED运用：Arizona眼睛模型 [复制链接]

简介 a|%J=k>>  
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。 "@%7-nu  
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模型 k.5u  
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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。 $;
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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. Sh/T,  
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光源 QqFR\6  

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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。 cJ{ Nh;"  
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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。 BzkooJ  
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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。 Wr<j!>J6Ki  
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视网膜的散射 !Y$h"<M  
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在散射文件中，有一个名为“Retina surface”的72%的反射型朗伯散射，它为视网膜的散射提供了一个粗略的近似。为了模拟来自视网膜的散射，改变自定义元件“Eye ball” 下的视网膜的表面从“halt all” 到”Allow All”。并使几何中“plane”可追迹。 Yk)."r
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注意在视网膜的表面有散射重点采样规格定义，在“Scatter”标签的底部可获取该信息。“toward pupil”指定散射光朝向光瞳，半角度10度。 )k\H@Dy%$  
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脚本 /JFUU[W  
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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： `);AW(Q  
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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。 c#|raXGT  
余下的脚本计算与屈光度有关的所有参数。 eFaO7mz5V%  
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分析 9Xj7~,  
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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。 N9jH\0nG  
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脚本代码 d*jMZ%@uS  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. j<Bkj/  
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Dim entity As T_ENTITY W yB3ls~  
Dim op As T_OPERATION R$
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Dim mat As T_MODELMATERIAL C"!gZ8*\!9  
Dim A As Double B.dH(um  
Dim pupilDiam As Double N.\- 8?>  
Dim eID As Long {_`^R>"\&w  
Dim parID As Long 5MN8D COF  
Dim count As Integer -db
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Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double *QwY]j%^  
Dim tlens As Double, nlens As Double J&M o%"[)  
Dim curv As Double, conic As Double $ {O#  
Dim ok As Long y`F3Hr c  
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Sub Main P
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    '用户输入对话框 xD5:RE~g  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 \9cG36  
        TextBox 220,21,40,21,.TextBox1 'default: 0 <~6h|F8  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 LS7, a|  
        OKButton 40,91,90,21 pm_`>3  
        CancelButton 190,91,90,21 `Gn50-@  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 N>XS=2tzN  
        TextBox 220,49,40,21,.TextBox2 'default: 4 g+pml*LJ  
    End Dialog (Dw,DY9  
    Dim dlg As UserDialog Y"~gw~7OD  
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    ok = Dialog (dlg) {[+mpKq
 
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    If ok=0 Then    'cancel button was pressed PmKeF}  
        Print "Execution cancelled."
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        End @)|C/oA  
    End If ,cB\  
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    'Assign accommodation and pupil diameter & use defaults if field left empty .#rJ+.2  
    If dlg.TextBox1 = "" Then LcUh;=r}&  
        A = 0           'Default accommodation |y0(Q V  
    Else N'^&\@)xiU  
        A = CDbl(dlg.TextBox1) L1cI`9  
    End If +
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    If dlg.TextBox2 = "" Then _H j!2 '  
        pupilDiam = 4   'Default pupil diameter y~q8pH1  
    Else n?- })  
        pupilDiam = CDbl(dlg.TextBox2) }T&iewk  
    End If Jtr"NS?a]  
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    Print " " {u#;?u=|  
    Print "Accommodation = " & A & " Diopters" t m7^yn:  
    Print "Pupil Diameter = " & pupilDiam & " mm" {]:7bV#JP  
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    ' Calculate new parameters with accommodation )}"wesNo".  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness f@Zszt  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens n/+.s(7c  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens G LIi6  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens (C@mLu)  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens ";3zXk[#  
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    tlens = 3.767 + 0.04*A                  'Lens thickness X*{2[+<o  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction ;[M}MFc/`  
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    'Adjust parameters to account for accommodation {(r`k;fB  
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    '************************************************************************* >zXsNeGQR  
    'Aqueous thickness (Position of Lens)
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    '*************************************************************************
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    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) FVaQEMZ^  
    GetCustomElement eID, entity ^,/R
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    parID = FindFullName( "Geometry.Arizona Eye" ) -"=U?>(  
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    ' Delete any shift(s) in z u>kN1kQ8  
    count = 0 P<M?Qd1.  
    While GetOperationCount(eID)>count kXi6lh  
        GetOperation eID, count, op g*03{l#P  
        If op.Type="ShiftZ" Then \=:~ki=@B  
            DeleteOperation eID,count Y@N,qHtz  
            count=count-1 $}>+kHoT{  
        End If .QZaGw=,z  
        count=count+1 Wu[&Wv~  
    Wend 7"20hAd  
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    'Set new shift in }:us:%  
    op.Type = "ShiftZ" :h\Q;?  
    op.val1 = taq H!5\v
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    op.parent = parID eZIhEOF  
    AddOperation eID, op KH(%?  
    Print "Set aqueous humor thickness = " & taq-0.55
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    '************************************************************************* j4jTSLQ\  
    'Radius and conic constant of anterior lens '8!YD?n  
    '************************************************************************* 2+QYhdw  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) 1(I6.BHW  
    GetConic eID, entity, curv, conic vms|x wb  
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    SetConic eID, entity, 1/Rant, CCant G6/p1xy>o:  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant 5ni~Q 9b  
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    '************************************************************************* ==3dEJS  
    'Radius and conic constant of posterior lens jbVECi-  
    '************************************************************************* &PYK8}pBk3  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) r+":'/[x  
    GetConic eID, entity, curv, conic MZSy6v  
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    SetConic eID, entity, 1/Rpost, CCpost *>|gxM8  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost f&BY/ n,  
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    '************************************************************************* /Z~<CbKKl  
    'Lens thickness (Position of posterior lens surface) 'gC_)rK*  
    '************************************************************************* bM{s T"  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) H*ow\ Ct  
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    ' Delete any z-shift(s) ]s'Q_wh_-v  
    count = 0 o]yl;I  
    While GetOperationCount(eID)>count F Sw\_[^CQ  
        GetOperation eID, count, op piPR=B+  
        If op.Type="ShiftZ" Then . $BUw  
            DeleteOperation eID,count Qw-~>d  
            count=count-1 `o=q%$f#k~  
        End If B* ?]H*K  
        count=count+1 1_9<3,7  
    Wend }&cu/o4  
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    'Set new z-shift =/s>Q l  
    op.Type = "ShiftZ" a1C{(f)  
    op.val1 = tlens X:HacYqtC  
    op.parent = parID sDPs G5q<  
    AddOperation eID, op W42iu"@  
    Print "Set lens thickness = " & tlens B"h#C!E  
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    '************************************************************************* /]K^ rw[  
    'Lens index of refraction ^2Fei.?T.  
    '************************************************************************* oI }VV6vO  
    eID = FindMaterial( "Lens" ) #M9~L[nFS  
    GetModelMaterial eID, mat 39:bzUIF  
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    mat.Nd = nlens -ws? "_w  
    SetModelMaterial eID, mat IpYM;tYw&  
    Print "Set lens index of refraction = " & nlens 5rw 7;'  


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    '************************************************************************* NjVYLn<.r  
    'Pupil diameter aI  P  
    '************************************************************************* .~~nUu+M  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) 4ezEW|S  
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    'Adjust pupil diameter (trimming volume inner hole) e7^mmm  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" QoI3>Oj=  
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    ' Adjust pupil location to just in front of the lens $ `ov4W  
    parID = FindFullName( "Geometry.Arizona Eye" ) C'9Cr}cZ.  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) SheM|I~de  
    count = 0 Ka
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    While GetOperationCount(eID)>count J%u=Ucdh  
        GetOperation eID, count, op o} J&E{Tk  
        If op.Type="ShiftZ" Then ,]bhyp  
            DeleteOperation eID,count Sdp&jZY  
            count=count-1 T1ut"
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        End If 6eLR2  
        count=count+1 &v56#lG  
    Wend '*K:  lx  
    op.Type = "ShiftZ" CyJEY-  
    op.val1 = taq-0.01 Oxm>c[R  
    op.parent = parID i6^twK)j  
    AddOperation eID, op 9B{k , 1  
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    Print "Set pupil diameter = " & pupilDiam ?4+9fE<Q  
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    'Update AZ Eye subassembly Description @Xt*Snd  
    eID = FindFullName( "Geometry.Arizona Eye" ) f86XkECZ;`  
    GetEntity eID, entity qraSRK5  
    entity.Description = "Accommodation = " & A & "D" nr95YSH  
    SetEntity eID, entity fY{1F   
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    Update '=39+*6?  
    Print "DONE!" C6VLy x  
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End Sub Y1OCLnK~  
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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： \K5DOM "#  
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Accommodation = 4 Diopters w^Sz#_2  
Pupil Diameter = 4 mm Lb!Fcf|h  
Set aqueous humor thickness = 2.81 B-xGX$<z  
Set anterior lens radius = 10.4 and conic constant = -2.375869 .k#U]M  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 '9laa=H%8  
Set lens thickness = 3.927 2y//
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Set lens index of refraction = 1.42672 V\>K]mwD  
Set pupil diameter = 4 q3mJ782p]  
DONE! 3-[q4R  
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