[转载]FRED运用：Arizona眼睛模型 [复制链接]

简介 !HCuae3_  
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。 \.K4tY+V  
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模型 <;P40jDL  
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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。 ,qu7XFYrY  
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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. D
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光源 reI4!,x  
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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。 5=hMTztf!!  
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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。 h\lyt(.s  
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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。 mbZn[D_zi  
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视网膜的散射 =Ohro'   
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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。 -jWXE  
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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。 iT=h}>  
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脚本 4WXr~?Vq9  
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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： OfPv'rW{x  
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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。 BT|n+Y[  
余下的脚本计算与屈光度有关的所有参数。 yW@YW_2;4  
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分析 nj=nSD  
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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。 [PH56f  
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脚本代码 q'KXn0IY#  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. N[&(e d=  
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Dim entity As T_ENTITY Yv"
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Dim op As T_OPERATION K`8$+JDP+  
Dim mat As T_MODELMATERIAL GsiT!OP]y  
Dim A As Double %`0*KMO3  
Dim pupilDiam As Double gr\vC  
Dim eID As Long qDPl( WXb  
Dim parID As Long `teaE7^Wm  
Dim count As Integer oH1]-Nl$  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double * TByAa{  
Dim tlens As Double, nlens As Double u&<NBxY  
Dim curv As Double, conic As Double =~q Xzq  
Dim ok As Long %o_CD>yD  
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Sub Main tUhr gc  
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    '用户输入对话框 6.6x$y3v  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 Fia
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        TextBox 220,21,40,21,.TextBox1 'default: 0 )NnkoCNeE  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 ,B$e'KQ  
        OKButton 40,91,90,21 I&>5b7Uf  
        CancelButton 190,91,90,21 \:>eZl?  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 t'*2)U  
        TextBox 220,49,40,21,.TextBox2 'default: 4 vPM2cc/o  
    End Dialog kY#sQz}8  
    Dim dlg As UserDialog $: qrh6
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    ok = Dialog (dlg) ~`<_xIvrq  
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    If ok=0 Then    'cancel button was pressed }0 =gP?.kE  
        Print "Execution cancelled." G$1gk^G's  
        End 0RP{_1k  
    End If .83z =  
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    'Assign accommodation and pupil diameter & use defaults if field left empty G&#l3bkQ  
    If dlg.TextBox1 = "" Then 2o1 RJk9  
        A = 0           'Default accommodation )]{&  
    Else VV"1IR  
        A = CDbl(dlg.TextBox1) 28O3N;a  
    End If w"OeS;#e:  
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    If dlg.TextBox2 = "" Then /,3:<I  
        pupilDiam = 4   'Default pupil diameter ]Ab$IKY  
    Else X@Yl<9|i  
        pupilDiam = CDbl(dlg.TextBox2) +?uZ~VSl  
    End If pF7S("#R
 
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    Print " " 9On(b|mT  
    Print "Accommodation = " & A & " Diopters" ^vc#)tm5p  
    Print "Pupil Diameter = " & pupilDiam & " mm" GL3olKnL  
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    ' Calculate new parameters with accommodation nACKSsWqI  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness H~~>ut6`  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens U_AmRiy  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens g/O
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens +6\1 d5  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens ^spASG-o  
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    tlens = 3.767 + 0.04*A                  'Lens thickness wsAijHjJI!  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction ?o_D#gG*  
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    'Adjust parameters to account for accommodation )k&!&  
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    '************************************************************************* #i|AE`  
    'Aqueous thickness (Position of Lens) e18}`<tW-  
    '************************************************************************* }+BbwBm&  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) TbR!u:J  
    GetCustomElement eID, entity qm|T<zsDY#  
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    parID = FindFullName( "Geometry.Arizona Eye" ) -+&sPrQ  
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    ' Delete any shift(s) in z H(ds  
    count = 0 lvIdYf$?  
    While GetOperationCount(eID)>count ]VHO'z\m  
        GetOperation eID, count, op $s!2D"wl n  
        If op.Type="ShiftZ" Then 'v_VyK*w  
            DeleteOperation eID,count N.|uPq$R  
            count=count-1 2[Vs@X  
        End If yn KgNi  
        count=count+1 o;7_*=i  
    Wend 17@#"uT0  
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    'Set new shift in Ib0@,yS[  
    op.Type = "ShiftZ" AOR(1Qyo  
    op.val1 = taq w$[ck=  
    op.parent = parID ys Td'J  
    AddOperation eID, op hT[w" &3  
    Print "Set aqueous humor thickness = " & taq-0.55 cA2
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    '************************************************************************* %$}*y   
    'Radius and conic constant of anterior lens ~+bSD<!b  
    '************************************************************************* f>jAu;S  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) ip2BvN&  
    GetConic eID, entity, curv, conic Ah1fcXED  
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    SetConic eID, entity, 1/Rant, CCant S$1dXXT  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant Nm,9xq  

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    '************************************************************************* V]0~BV  
    'Radius and conic constant of posterior lens }pL#C  
    '************************************************************************* 0ZjinWkR[  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) jY ~7-  
    GetConic eID, entity, curv, conic br_D Orq|  
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    SetConic eID, entity, 1/Rpost, CCpost m{C  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost 5_= HtM[v]  
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    '************************************************************************* ;-@v1I;  
    'Lens thickness (Position of posterior lens surface) !%Qm{R  
    '************************************************************************* =U_O;NC  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) 18kzR6(W  
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    ' Delete any z-shift(s) LFT)_DG7(  
    count = 0 ,pMH`  
    While GetOperationCount(eID)>count fKjUEMRK  
        GetOperation eID, count, op |%xgob  
        If op.Type="ShiftZ" Then KL6FmL)HH  
            DeleteOperation eID,count )H`1CcT  
            count=count-1 mQy!*0y  
        End If zTQTmO  
        count=count+1 @"gWvs  
    Wend B|(MxR6m  
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    'Set new z-shift QeZK&^W  
    op.Type = "ShiftZ" "0#d F:qt  
    op.val1 = tlens 0N(o)WRv  
    op.parent = parID 95^A !  
    AddOperation eID, op :{ Q[kYj  
    Print "Set lens thickness = " & tlens tf_<w?~  
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    '************************************************************************* (zL(  
    'Lens index of refraction XlHt(d0h
 
    '************************************************************************* 1#-=|:U  
    eID = FindMaterial( "Lens" ) 'k?*?XxG  
    GetModelMaterial eID, mat M5>cYVG  
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    mat.Nd = nlens N56/\1R  
    SetModelMaterial eID, mat 
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    Print "Set lens index of refraction = " & nlens uDXRw*rTv  
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    '************************************************************************* E ) iEWc  
    'Pupil diameter haW*W=kv)  
    '************************************************************************* XAF*jevr  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) _6k ej#o8  
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    'Adjust pupil diameter (trimming volume inner hole) p&|:,|jo5  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" 2J5RZg9jL  
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    ' Adjust pupil location to just in front of the lens Bp>Z?"hTe  
    parID = FindFullName( "Geometry.Arizona Eye" ) cgevP`*]  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) #`(-Oj2hH  
    count = 0 sj& j\<(  
    While GetOperationCount(eID)>count "Gh5 ^$w?j  
        GetOperation eID, count, op F vt5vQ  
        If op.Type="ShiftZ" Then zEYT,l  
            DeleteOperation eID,count krI@N}OU  
            count=count-1 Oj~4uT&"  
        End If JNZ
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        count=count+1 W+&<C#1|]  
    Wend />,KWHR|:  
    op.Type = "ShiftZ" PA_54a9/<  
    op.val1 = taq-0.01 0M_~@E*&  
    op.parent = parID s}5,<|DL  
    AddOperation eID, op py8)e7gX=  
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    Print "Set pupil diameter = " & pupilDiam U3UDA  
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    'Update AZ Eye subassembly Description *[SOz)  
    eID = FindFullName( "Geometry.Arizona Eye" ) k9Xv@v  
    GetEntity eID, entity -0o1iU7  
    entity.Description = "Accommodation = " & A & "D" y.PsC '  
    SetEntity eID, entity ]6BV`r]  
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    Update aUTXg60l*  
    Print "DONE!" lI"~*"c`  
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End Sub =Mby;wQ?|  
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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： Z>t,B%v  
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Accommodation = 4 Diopters #5b}"xK{  
Pupil Diameter = 4 mm vl,Ff9  
Set aqueous humor thickness = 2.81 nB .?=eUa  
Set anterior lens radius = 10.4 and conic constant = -2.375869 8,DY0PGP  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 JsZLBq*lP  
Set lens thickness = 3.927 ;[,r./XmH  
Set lens index of refraction = 1.42672 rOyKugHe  
Set pupil diameter = 4 [')C]YQb=  
DONE! W#@Mx  
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