[转载]FRED运用：Arizona眼睛模型 [复制链接]

简介 eNQQ`
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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。 Fj_6jsDb  
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模型 s%6{X48vY^  
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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。 =%i~HDiy  
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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. f4mQDRlD  
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光源 oe4r_EkYwW  
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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。 mO~A}/je  
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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。 0s+pcqOd^  
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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。 A\S1{JrR  
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视网膜的散射 5Z
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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。 0A.PfqY
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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。 )VoQ/ch<  
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脚本 ~3F\7%Iqc  
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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： /H m),9NN  
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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。 7HkQ|~zGT  
余下的脚本计算与屈光度有关的所有参数。 |DZ3=eWZ  
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分析 gY=Ry=w9  
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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。 X8Ld\vZYn  
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脚本代码 )rP)-op|A  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. HvSYE[Zt|  
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Dim entity As T_ENTITY G>q16nS~KP  
Dim op As T_OPERATION m=7Z8@sX},  
Dim mat As T_MODELMATERIAL O{F)|<L(G  
Dim A As Double NcVsQV  
Dim pupilDiam As Double "BAH=ul5E  
Dim eID As Long O*d4zBT  
Dim parID As Long 'z}Hg *  
Dim count As Integer [=xJh?*P  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double ju= +!nGUa  
Dim tlens As Double, nlens As Double zJJ6"9sl  
Dim curv As Double, conic As Double {g7[3WRy  
Dim ok As Long W18I"lHeh  
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Sub Main $^1L|KgXp  

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    '用户输入对话框 n!*uv~%$  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 +u
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        TextBox 220,21,40,21,.TextBox1 'default: 0 ra'h\m  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 ~il{6Z+#n  
        OKButton 40,91,90,21 lv*fK  
        CancelButton 190,91,90,21 3nJd0E  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 +z2+z  
        TextBox 220,49,40,21,.TextBox2 'default: 4 O!c b-  
    End Dialog nvdo
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    Dim dlg As UserDialog [v!TQwMU  
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    ok = Dialog (dlg) >(t_  
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    If ok=0 Then    'cancel button was pressed j$K[QSn  
        Print "Execution cancelled." TBzOz:k  
        End (Wm4JmX%  
    End If DG&[.dR+  
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    'Assign accommodation and pupil diameter & use defaults if field left empty 'xC83}!k  
    If dlg.TextBox1 = "" Then /W6r{Et  
        A = 0           'Default accommodation T|c9Swur  
    Else t`XYY  
        A = CDbl(dlg.TextBox1) f#W5Nu'*!  
    End If 1M4I7*r  
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    If dlg.TextBox2 = "" Then s]X]jfA.  
        pupilDiam = 4   'Default pupil diameter *vss  
    Else onuhNn_=>  
        pupilDiam = CDbl(dlg.TextBox2)  MR/8  
    End If bLfbzkNV\1  
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    Print " " KvM}g2"  
    Print "Accommodation = " & A & " Diopters" $:YJ<HvG<  
    Print "Pupil Diameter = " & pupilDiam & " mm" B`/cKfg  
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    ' Calculate new parameters with accommodation 3xJ_
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    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness j|u6TG  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens 5Y4i|R  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens +U%U3tAvs  

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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens "SuBtoK  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens zlh}8Es  
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    tlens = 3.767 + 0.04*A                  'Lens thickness mv1_vF:  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction *Q<%(JJ  
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    'Adjust parameters to account for accommodation %EZG2JjO)  
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    '************************************************************************* mxYsP6&  
    'Aqueous thickness (Position of Lens) dJhT}"x  
    '************************************************************************* !KUV,>L  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) rf%E+bh4  
    GetCustomElement eID, entity :(,Eq?
  
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    parID = FindFullName( "Geometry.Arizona Eye" ) BVx: JiA  
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    ' Delete any shift(s) in z 0Wf,SYx`s  
    count = 0 T5eXcI0t  
    While GetOperationCount(eID)>count >qJRpO  
        GetOperation eID, count, op {=AK|  
        If op.Type="ShiftZ" Then :eK;:p
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            DeleteOperation eID,count *{]9e\DF  
            count=count-1 V}l>p?  
        End If QY,.|  
        count=count+1 HR85!S`  
    Wend 8 0>qqz  
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    'Set new shift in a*}ZT,V  
    op.Type = "ShiftZ" #L-3eW=f  
    op.val1 = taq F<y5zqGy@  
    op.parent = parID \ORNOX:  
    AddOperation eID, op =TDK$Ek  
    Print "Set aqueous humor thickness = " & taq-0.55 lO-:[@  
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    '************************************************************************* XD5z+/F<"0  
    'Radius and conic constant of anterior lens aDx{Q&  
    '************************************************************************* Ks.pb !r  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) K8.=bGyg  
    GetConic eID, entity, curv, conic N#')Qz:P  
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    SetConic eID, entity, 1/Rant, CCant ;r[@;2p*(  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant */Oq$3QGsV  
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    '************************************************************************* 3A_7R-sQ  
    'Radius and conic constant of posterior lens R qS2Qo]  
    '************************************************************************* s4 o-*1R*`  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" )
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    GetConic eID, entity, curv, conic X[:&p|g]  
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    SetConic eID, entity, 1/Rpost, CCpost @0q%&v0  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost K9FtFd  
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    '************************************************************************* +I
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    'Lens thickness (Position of posterior lens surface) hlxZq  
    '************************************************************************* odPq<'V|AY  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) A]2zK?|s  
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    ' Delete any z-shift(s) ?]}1FP
 
    count = 0 T<\Q4Coth  
    While GetOperationCount(eID)>count {Slc6$  
        GetOperation eID, count, op I\O<XJO)_  
        If op.Type="ShiftZ" Then ~S)o('  
            DeleteOperation eID,count iIwMDlQ "  
            count=count-1 i,BE]w  
        End If QDS=M]  
        count=count+1 0nS69tH  
    Wend ~Rx[~a  
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    'Set new z-shift |q5R5m
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    op.Type = "ShiftZ" Kw}-<y  
    op.val1 = tlens q9w6 6R  
    op.parent = parID UBp0;)-  
    AddOperation eID, op )/h~csy:~  
    Print "Set lens thickness = " & tlens xtyzy@)QL  
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    '************************************************************************* s5>=!yX  
    'Lens index of refraction ]sJWiIe.  
    '************************************************************************* XM$r,}B k  
    eID = FindMaterial( "Lens" ) +2=N#LM  
    GetModelMaterial eID, mat -tWkN^j8+  
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    mat.Nd = nlens <;:M:{RZY  
    SetModelMaterial eID, mat _ 97  
    Print "Set lens index of refraction = " & nlens >h/J{T(P>h  
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    '************************************************************************* +5Yc/Qp  
    'Pupil diameter "q4c[dna  
    '************************************************************************* ++-\^'&1  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) 4flyV -  
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    'Adjust pupil diameter (trimming volume inner hole) }wrZP}zM>  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" S+A'\{f  
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    ' Adjust pupil location to just in front of the lens =jjUwcl  
    parID = FindFullName( "Geometry.Arizona Eye" ) dL'hC#!h  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) l?v-9l M  
    count = 0 QA\eXnR  
    While GetOperationCount(eID)>count iIu  
        GetOperation eID, count, op |*"uj  
        If op.Type="ShiftZ" Then hHF YAh   
            DeleteOperation eID,count .Ya]N+r*  
            count=count-1 ^
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        End If uBw1Xud[YI  
        count=count+1 8'?V5.6?|~  
    Wend a0OH  
    op.Type = "ShiftZ"  B\1F  
    op.val1 = taq-0.01 EZ*FGt6(  
    op.parent = parID -XIjol(  
    AddOperation eID, op a?K=  
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    Print "Set pupil diameter = " & pupilDiam ,#rl"  
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    'Update AZ Eye subassembly Description $}r*WZ  
    eID = FindFullName( "Geometry.Arizona Eye" ) oX@nWQBc_  
    GetEntity eID, entity |&WeXVH E  
    entity.Description = "Accommodation = " & A & "D" _Dl!iV05:  
    SetEntity eID, entity 9'C k
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    Update ~aa`Y0Ws],  
    Print "DONE!" LJDX6]4n  
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End Sub 'h_PJ%  
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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： bvzeUn  
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Accommodation = 4 Diopters ]W3D4Swq  
Pupil Diameter = 4 mm Q[`J=  
Set aqueous humor thickness = 2.81 \^vf`-uG  
Set anterior lens radius = 10.4 and conic constant = -2.375869 _@jBz"aq\  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 c%c/mata?  
Set lens thickness = 3.927 ww82)m8  
Set lens index of refraction = 1.42672 o1=
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Set pupil diameter = 4 He="S3XON  
DONE! =XsdR?C  
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