[转载]FRED运用：Arizona眼睛模型 [复制链接]

简介 R3$K[Lv,  
人眼光学模型可用来设计眼科用设备，光学系统注定了要与人眼一起使用。本文演示了这样一个模型：Arizona眼睛模型，在Jim Schwiegerling教授的书中有详细描述：《Field Guide to Visual and Ophthalmic Optics》。AZ眼睛模型达到了基于平均临床数据所决定的轴上和轴外像差等级。FRED文件包含了此眼睛模型及几个用来分析它的光源，并包括一个基于想要的屈光度来调整模型的内嵌脚本。 F*_mHYa;  
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模型 [yF4_UoF  
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模型的定义如表1种所示，由半径、圆锥常数、折射率、阿贝数、到下一面的距离等一系列表面组成。一些参数由屈光度（A）来决定。 r$*p  
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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. 9*%Uoy:  
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光源 ;TK:D=p4  
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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。 =B(zW.Gf  
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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。 #GYCU!  
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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。 ]~z2s;J{/  
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视网膜的散射 Nd&u*&S  
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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。 FxC@KZG  
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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。 Xv'M\T}6C+  
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脚本 m?_S&/+*  
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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： f4zd(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。 Rtn.cSd  
余下的脚本计算与屈光度有关的所有参数。 MOyQ4<_  
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分析 K ^1bR(a  
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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。 H~@E&qd  
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脚本代码 RaAi9b[/S  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. jd=k[Yqr  
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Dim entity As T_ENTITY |-I[{"6q$@  
Dim op As T_OPERATION LZyUlz  
Dim mat As T_MODELMATERIAL '1=t{Rw
 
Dim A As Double bzmT.!  
Dim pupilDiam As Double AFl]w'=  
Dim eID As Long 9S.Uo[YY  
Dim parID As Long TC3xrE:U<m  
Dim count As Integer j%b/1@I  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double @q2Yka  
Dim tlens As Double, nlens As Double ZYrXav<  
Dim curv As Double, conic As Double rU5gQq
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Dim ok As Long ow ~(k5k:  
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Sub Main ^l ~i>:V  
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    '用户输入对话框 dV8mI,h  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 1Af~6jz  
        TextBox 220,21,40,21,.TextBox1 'default: 0 j"/i+r{"E  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 sW#6B+5_k  
        OKButton 40,91,90,21 '>Y"s|  
        CancelButton 190,91,90,21 ^!1mChf  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 AU$W=Z*  
        TextBox 220,49,40,21,.TextBox2 'default: 4 I1 j-Q8  
    End Dialog #Z}\;a{vZ  
    Dim dlg As UserDialog %K /=7  
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    ok = Dialog (dlg) :sFP{rFx~  
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    If ok=0 Then    'cancel button was pressed ;p/RS#  
        Print "Execution cancelled." #~q{6()e:  
        End uE-~7Q(@  
    End If 7Cx%G/(  
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    'Assign accommodation and pupil diameter & use defaults if field left empty _UYt  
    If dlg.TextBox1 = "" Then FlRbGg^  
        A = 0           'Default accommodation \Zqgr/.w/  
    Else ;_,=  
        A = CDbl(dlg.TextBox1) U/m6% )Yx(  
    End If 2md1GWyP  
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    If dlg.TextBox2 = "" Then jhUab],  
        pupilDiam = 4   'Default pupil diameter X26gl 'U  
    Else 'u{m37ZJ  
        pupilDiam = CDbl(dlg.TextBox2) v1QE|@  
    End If Gb<)U[Hfd  
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    Print " " ~a4htj  
    Print "Accommodation = " & A & " Diopters" x,STt{I=  
    Print "Pupil Diameter = " & pupilDiam & " mm" @/ wJW``;  
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    ' Calculate new parameters with accommodation #]oVVf_  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness A/,7%bB1  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens ^* ^te+N  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens ]ZelB,7q  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens i))S%!/r~  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens bPAp0}{Fu  
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    tlens = 3.767 + 0.04*A                  'Lens thickness ync2X{9D  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction mrX3/e  
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    'Adjust parameters to account for accommodation d Ayof=  
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    '************************************************************************* wLPL9  
    'Aqueous thickness (Position of Lens) 7KnZ  
    '************************************************************************* -]~&Pi|  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) `$j
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    GetCustomElement eID, entity b!J21cg<L  
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    parID = FindFullName( "Geometry.Arizona Eye" ) 0 ML=]  
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    ' Delete any shift(s) in z Ka&[ Oz<w  
    count = 0 d,CtlWp  
    While GetOperationCount(eID)>count p[VBeO^%  
        GetOperation eID, count, op FylL7n  
        If op.Type="ShiftZ" Then K3$83%E  
            DeleteOperation eID,count Pdmfn8I]%  
            count=count-1 L"&j(|{  
        End If 57Q^"sl  
        count=count+1 CDQ}C=4  
    Wend Lo\+T+n  
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    'Set new shift in ^I@1y}xi  
    op.Type = "ShiftZ" D'F=v\P  
    op.val1 = taq ^]3Y11sI  
    op.parent = parID BK]bSj  
    AddOperation eID, op `/#f8R1g  
    Print "Set aqueous humor thickness = " & taq-0.55 tI|?k(D  
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    '************************************************************************* INOw0E[  
    'Radius and conic constant of anterior lens X(U CN0#  
    '************************************************************************* oJ\UF S  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) d>*?C!xE  
    GetConic eID, entity, curv, conic V.vA~a  
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    SetConic eID, entity, 1/Rant, CCant MU4/arXy  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant "G-} wt+P  
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    '************************************************************************* {5QIQ  
    'Radius and conic constant of posterior lens <
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    '************************************************************************* x+x6F  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) z 0]K:YV_  
    GetConic eID, entity, curv, conic v*SSc5gFG  
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    SetConic eID, entity, 1/Rpost, CCpost o@mZ6!ax3  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost "5"6mw?  
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    '*************************************************************************
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    'Lens thickness (Position of posterior lens surface) ;,![Lar5L  
    '************************************************************************* ~CgKU8  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" )
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    ' Delete any z-shift(s) Y u\
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    count = 0 HgPRz C  
    While GetOperationCount(eID)>count YhYcqE8  
        GetOperation eID, count, op 1OJD!juL$  
        If op.Type="ShiftZ" Then Fk@A;22N  
            DeleteOperation eID,count 8\+kfK  
            count=count-1 rxH*h`Xx@  
        End If }CnqJ@>C5  
        count=count+1 P9=L?t.  
    Wend U]tbV<m%  
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    'Set new z-shift 7cV9xIe^  
    op.Type = "ShiftZ" 6nqG;z-IXJ  
    op.val1 = tlens u;\:#721  
    op.parent = parID np,L39:sf  
    AddOperation eID, op Oa~|a7`o  
    Print "Set lens thickness = " & tlens !Z[dK{f"  
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    '************************************************************************* Kk#g(YgNz  
    'Lens index of refraction tgXIj5z  
    '************************************************************************* hbRDM'  
    eID = FindMaterial( "Lens" ) T\ZWKx*#  
    GetModelMaterial eID, mat c`}-i6  
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    mat.Nd = nlens 8 #fzL7  
    SetModelMaterial eID, mat Y[Jt+p]  
    Print "Set lens index of refraction = " & nlens /cHd&i,>  
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    '************************************************************************* bh9
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    'Pupil diameter  $0>>Z  
    '************************************************************************* "S#4  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) ]v
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    'Adjust pupil diameter (trimming volume inner hole) 3Z=OUhn9  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" '{=dEEi  
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    ' Adjust pupil location to just in front of the lens +]Ca_`  
    parID = FindFullName( "Geometry.Arizona Eye" ) $ZX^JWq  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) zy\p,  
    count = 0 ;d$PQi  
    While GetOperationCount(eID)>count 9l).L L  
        GetOperation eID, count, op *#+e_)d  
        If op.Type="ShiftZ" Then \pI)tnu6'U  
            DeleteOperation eID,count ?w'a^+H  
            count=count-1 4/YE
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        End If W:D'k^u  
        count=count+1 @V{s'V   
    Wend AZ' "M{wiI  
    op.Type = "ShiftZ" cpz'upVOZ  
    op.val1 = taq-0.01 n5CjwLgu\b  
    op.parent = parID ~Wy&xs ZH  
    AddOperation eID, op E^uau=F  
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    Print "Set pupil diameter = " & pupilDiam 3GVE/GtU  
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    'Update AZ Eye subassembly Description '@enl]J  
    eID = FindFullName( "Geometry.Arizona Eye" ) cx%[hM09  
    GetEntity eID, entity  .b] 32Ww  
    entity.Description = "Accommodation = " & A & "D" AQkH3p/W  
    SetEntity eID, entity 0tbximmDb  
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    Update iC-WQkQY  
    Print "DONE!" 2>~{.4PI  
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End Sub }G^Bc4@b  

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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： 7oY}=281  
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Accommodation = 4 Diopters Cb}hE ro  
Pupil Diameter = 4 mm 3&Dln  
Set aqueous humor thickness = 2.81 v_Om3i9$E  
Set anterior lens radius = 10.4 and conic constant = -2.375869 tln*Baq  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 TAz
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Set lens thickness = 3.927 c%1<O!c  
Set lens index of refraction = 1.42672 Q*wub9  
Set pupil diameter = 4 4k'2FkDA  
DONE! 2yqm$i9C  
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