[转载]FRED运用：Arizona眼睛模型 [复制链接]

简介 7KEGTKfW  
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。 KIS.4nt#d"  
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模型 7%<jZ=  
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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。 0TNzVsu7  
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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. gV7o eZ5  
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光源 D9Z5g3s7R  
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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。 f]lDJ?+ M  
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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。 >!2'|y^  
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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。 B^qB6:\t  
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视网膜的散射 pxF!<nN1,  
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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。 {\e}43^9N  
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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。 ieI-_]|[  
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脚本 pGFocw  
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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： oMPQkj;  
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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。 pIXQ/(h31  
余下的脚本计算与屈光度有关的所有参数。 "duJl-  
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分析 9Dl \SF[  
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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。 :-Pj )Y{I  
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脚本代码 2R!W5gs1<  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. 4Bn+L,}.  
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Dim entity As T_ENTITY
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Dim op As T_OPERATION KkY22_{ac  
Dim mat As T_MODELMATERIAL pr"flRQr#  
Dim A As Double 1<83MO;  
Dim pupilDiam As Double a|NU)mgEI  
Dim eID As Long Go|65Z\`7M  
Dim parID As Long &u8c!;y$b  
Dim count As Integer ,zFN3NLtA  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double lg1D>=(mY  
Dim tlens As Double, nlens As Double | QA8"&r  
Dim curv As Double, conic As Double if'4MDl  
Dim ok As Long b<n)`;  
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Sub Main 8'_Y=7b0Nw  
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    '用户输入对话框 0"`skYJ@  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 NSq=_8  
        TextBox 220,21,40,21,.TextBox1 'default: 0 @jHio\/_  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 wLbngO=VG  
        OKButton 40,91,90,21 St`m52V(5X  
        CancelButton 190,91,90,21 B^9 #X5!  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 7 SZR#L  
        TextBox 220,49,40,21,.TextBox2 'default: 4 ;j=1 oW  
    End Dialog BpT&vbY  
    Dim dlg As UserDialog 9x!y.gx  
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    ok = Dialog (dlg) gL`SZr9  
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    If ok=0 Then    'cancel button was pressed ,)1e+EnV&  
        Print "Execution cancelled." %a `dOEO  
        End w3>|mDA}I  
    End If AHGcWS\,X  
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    'Assign accommodation and pupil diameter & use defaults if field left empty ([~`{,sv  
    If dlg.TextBox1 = "" Then t^hkGYj!2  
        A = 0           'Default accommodation &u-Bu;G.e  
    Else "=.|QKC1`  
        A = CDbl(dlg.TextBox1) Oe`t!&v  
    End If G.8b\E~  
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    If dlg.TextBox2 = "" Then [2V/v  
        pupilDiam = 4   'Default pupil diameter ]||=<!^kn  
    Else Hea<!zPH  
        pupilDiam = CDbl(dlg.TextBox2) "[yiNJ"kt  
    End If T*yveo&j  
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    Print " " Umg81!  
    Print "Accommodation = " & A & " Diopters" EB<q.  
    Print "Pupil Diameter = " & pupilDiam & " mm" G,*s9P]1  
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    ' Calculate new parameters with accommodation sfE8b/Z8  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness Q%^bA,$&D  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens Z"X*FzFo  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens o"[bIXf-h  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens mC92J@m/L!  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens Q
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    tlens = 3.767 + 0.04*A                  'Lens thickness 2]=I'U<E!  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction ^~
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    'Adjust parameters to account for accommodation X:&p9_O@  
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    '************************************************************************* \[1CDz=}1  
    'Aqueous thickness (Position of Lens) RI3{>|*  
    '************************************************************************* e-3pg?M  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) `sy &dyM  
    GetCustomElement eID, entity OG7v'vmY  
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    parID = FindFullName( "Geometry.Arizona Eye" ) O)%kl  
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    ' Delete any shift(s) in z '8kjTf#g<l  
    count = 0 \Rqh|T<D  
    While GetOperationCount(eID)>count sJK:xk.6!  
        GetOperation eID, count, op w })Pedg  
        If op.Type="ShiftZ" Then ugCS &  
            DeleteOperation eID,count jI`To%^Y  
            count=count-1 p[F=LP  
        End If Q;ZHx.ye{  
        count=count+1 V,"iMo  
    Wend k5QD5/Ej  
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    'Set new shift in `W$0T;MPF  
    op.Type = "ShiftZ" ]!G>8Rc  
    op.val1 = taq G4%M$LJh  
    op.parent = parID |z.GSI_!)  
    AddOperation eID, op vs)I pV(  
    Print "Set aqueous humor thickness = " & taq-0.55 NwlRPyt  
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    '************************************************************************* k.xv+^b9Q  
    'Radius and conic constant of anterior lens 6(^Upk=59  
    '************************************************************************* yX.5Y|A<  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) ?Ga2K  
    GetConic eID, entity, curv, conic Rk jKIa  
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    SetConic eID, entity, 1/Rant, CCant JRjMt-7H_  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant 9#T%bB"J  
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    '************************************************************************* Ms'TC;&PS  
    'Radius and conic constant of posterior lens P[I*%  
    '************************************************************************* Z++Z@J"  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) @S"pJeP/f  
    GetConic eID, entity, curv, conic acYoOW1G  
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    SetConic eID, entity, 1/Rpost, CCpost w^rb|mKo  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost 5Jhbf2-  
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    '************************************************************************* _E1]cbIo  
    'Lens thickness (Position of posterior lens surface) SXo[[ao  
    '************************************************************************* kV:FJx0xP  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) 3Da,]w<  
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    ' Delete any z-shift(s) 3aE[F f[  
    count = 0 e8ULf~I  
    While GetOperationCount(eID)>count F;Q_*0mIQ  
        GetOperation eID, count, op '6.>Wdd  
        If op.Type="ShiftZ" Then vJj:9KcP>h  
            DeleteOperation eID,count uO_,n  
            count=count-1 ]o[X+;Tj|  
        End If 3$$5Mk(&  
        count=count+1 wCU&Xb$F  
    Wend Cwsoz  
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    'Set new z-shift Z.aLk4QO@  
    op.Type = "ShiftZ" ])QO%  
    op.val1 = tlens 4kaE}uKU  
    op.parent = parID @!":(@3[  
    AddOperation eID, op R?bn,T>  
    Print "Set lens thickness = " & tlens KcmDF4C2
 
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    '************************************************************************* 8!uL-_Bn  
    'Lens index of refraction ^Cc8F3os=  
    '************************************************************************* ;zZ,3pl-E  
    eID = FindMaterial( "Lens" ) S_|9j{w)  
    GetModelMaterial eID, mat Q3BLL`W~  
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    mat.Nd = nlens k(-Z@  
    SetModelMaterial eID, mat Z{a{HX[Jx  
    Print "Set lens index of refraction = " & nlens c_qcb7<~.  
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    '************************************************************************* b(|%Gbg@c  
    'Pupil diameter VBbUl|X\  
    '************************************************************************* Tsm1C#6 Y*  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) YeRcf`  
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    'Adjust pupil diameter (trimming volume inner hole) `jb0+{08  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" &Rt+LN0qB0  
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    ' Adjust pupil location to just in front of the lens x1m8~F  
    parID = FindFullName( "Geometry.Arizona Eye" ) qPXANx<^  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) FG>;P]mvp  
    count = 0 Pn'`Q S?  
    While GetOperationCount(eID)>count /'&.aGW4%  
        GetOperation eID, count, op ";)r*UgR{B  
        If op.Type="ShiftZ" Then %;pD8WgJA  
            DeleteOperation eID,count b?Cmc  
            count=count-1 W>p\O9BG  
        End If UOR _M5  
        count=count+1 mD D4_E2*  
    Wend DL'd&;6  
    op.Type = "ShiftZ" B#HnPUUK  
    op.val1 = taq-0.01 lnC!g
 
    op.parent = parID BG
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    AddOperation eID, op ",~ b2]ym  
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    Print "Set pupil diameter = " & pupilDiam y\F`B0#$  
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    'Update AZ Eye subassembly Description YH<$ +U  
    eID = FindFullName( "Geometry.Arizona Eye" ) _L*f8e8  
    GetEntity eID, entity xNC* ]8d  
    entity.Description = "Accommodation = " & A & "D" W:VW_3  
    SetEntity eID, entity l9_m>X~  
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    Update Rz.i/wg}  
    Print "DONE!" #'J~Xk   
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End Sub sTd}cP  
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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： $!3gN%  
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Accommodation = 4 Diopters hf_R\C(c  
Pupil Diameter = 4 mm R&NpdW N  
Set aqueous humor thickness = 2.81 r@|R-Binz  
Set anterior lens radius = 10.4 and conic constant = -2.375869 r> Fec  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 6b%`^B\  
Set lens thickness = 3.927 !?BW_vY  
Set lens index of refraction = 1.42672 kjx>  
Set pupil diameter = 4 SW3wMPy&s  
DONE! &[NVP&9&U  
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