[分享]Arizona眼睛模型 [复制链接]

简介 7*Gg#XQ>(  
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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。 R36A_  
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模型 9iK%@k  
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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。 [@$t35t~  
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在FRED中使用0屈光度来创建的，光瞳加在了透镜的前面。材料是创建一个新的材料并选择类型“Model Material”,输入的参数是nd和vd. ZlL]AD@  
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光源 io$fL_R=  
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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。 p<(b^{EX  
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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。 tNDv[I
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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。 x?G"58  
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视网膜的散射 K!|J/W  
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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。 PCiwQ4~  
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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。 {} Zqaf  
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脚本 Uizg.<.  
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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： t
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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。 -h,?_d>  
余下的脚本计算与屈光度有关的所有参数。 3|1v)E  
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分析 2$yNryd  
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屈光度为4，光瞳直径为4mm，字母F点在视网膜上所成的像。 Dq9*il;'  
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脚本代码 PI$K+}E  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. G Y+li{  
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Dim entity As T_ENTITY C;XhnqWv+l  
Dim op As T_OPERATION cPPTGpqw  
Dim mat As T_MODELMATERIAL +;N;r/d_i  
Dim A As Double 'Em633  
Dim pupilDiam As Double a3SBEkC  
Dim eID As Long Yp;?Zq9  
Dim parID As Long em?Q4t  
Dim count As Integer }o@Dsx5  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double A\)~y{9bQ  
Dim tlens As Double, nlens As Double `-w;/A"MJ  
Dim curv As Double, conic As Double T8>aU  
Dim ok As Long
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Sub Main I"2*}v|  
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    '用户输入对话框 V&J'2Lq  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 ~Nn}FNe  
        TextBox 220,21,40,21,.TextBox1 'default: 0 @k||gQqIB  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 m,PiuR>  
        OKButton 40,91,90,21 aQglA  
        CancelButton 190,91,90,21 t-)d*|2n}o  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 &r1]A&  
        TextBox 220,49,40,21,.TextBox2 'default: 4 !p{
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    End Dialog cng166}1A  
    Dim dlg As UserDialog b>L?0p$ej  
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    ok = Dialog (dlg) 5
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    If ok=0 Then    'cancel button was pressed WlmkM?@  
        Print "Execution cancelled." 9i+`,r  
        End _~O*V&  
    End If ,#K{+1z:  
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    'Assign accommodation and pupil diameter & use defaults if field left empty ^JAp#?N^9  
    If dlg.TextBox1 = "" Then J(w 3A)(  
        A = 0           'Default accommodation 0?O$->t  
    Else 5+
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        A = CDbl(dlg.TextBox1) CO`?M,x>  
    End If I*H($ a  
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    If dlg.TextBox2 = "" Then t:*1*;  
        pupilDiam = 4   'Default pupil diameter 8~ u/gM  
    Else IO<Ds#(  
        pupilDiam = CDbl(dlg.TextBox2) z"f+;1  
    End If h`f$]_c  
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    Print " " .Ky)Co  
    Print "Accommodation = " & A & " Diopters" "w3%BbIx  
    Print "Pupil Diameter = " & pupilDiam & " mm" DqHJ *x4  
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    ' Calculate new parameters with accommodation o2!wz8  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness a] 7nK+N  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens U<<XeSp  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens bD.KD)5  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens 06]"{2  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens UT0}Ce>e  
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    tlens = 3.767 + 0.04*A                  'Lens thickness Ako]34Rl,  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction Q hdG(`PY~  
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    'Adjust parameters to account for accommodation RoNE7|gF:  
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    '************************************************************************* Y=t?"E  
    'Aqueous thickness (Position of Lens) Yz#E0aTTA  
    '************************************************************************* d'iSvd.  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) k~)@D| ?  
    GetCustomElement eID, entity nf1O8FwRb  
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    parID = FindFullName( "Geometry.Arizona Eye" ) .q1y)l-^Z  
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    ' Delete any shift(s) in z MV]`[^xQ5  
    count = 0 U9jdb9 |  
    While GetOperationCount(eID)>count &hih p"  
        GetOperation eID, count, op 3^5h:OaT  
        If op.Type="ShiftZ" Then 6-FM<@H{  
            DeleteOperation eID,count KW$.Yy  
            count=count-1 8:[ l1d86  
        End If  \>||  
        count=count+1 y?U@F/^}N  
    Wend ae" o|Q  
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    'Set new shift in L7R!,  
    op.Type = "ShiftZ" sDAP'&  
    op.val1 = taq -fp/3-  
    op.parent = parID z/fSstN  
    AddOperation eID, op \Foo:jON  
    Print "Set aqueous humor thickness = " & taq-0.55 d"L(eI}G  
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    '************************************************************************* S|af?IW  
    'Radius and conic constant of anterior lens X ]W)D S  
    '************************************************************************* g#`}HuPoE  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) AN3oh1xe:  
    GetConic eID, entity, curv, conic HJBGxyw  
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    SetConic eID, entity, 1/Rant, CCant 41P0)o  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant Kwi+}B!  
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    '************************************************************************* Jg)( F|>o  
    'Radius and conic constant of posterior lens $0vWC#.A]  
    '************************************************************************* 'n=bQ"bQu  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) |P`b"x  
    GetConic eID, entity, curv, conic hQ(^;QcSu  
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    SetConic eID, entity, 1/Rpost, CCpost .)=*Yr M  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost \GQRpJ#h1  
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    '************************************************************************* QUaV;6 4  
    'Lens thickness (Position of posterior lens surface) EV-sEl8ki  
    '*************************************************************************  fDqDU  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) }a#T\6rY  
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    ' Delete any z-shift(s) 9HEqB0|ZRu  
    count = 0 _`gkYu3R+  
    While GetOperationCount(eID)>count bRrSd:e  
        GetOperation eID, count, op Na@;F{  
        If op.Type="ShiftZ" Then  JZ+6)R  
            DeleteOperation eID,count w>8kBQ
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            count=count-1 v9FR  
        End If [VqiF~o,  
        count=count+1 X)6G:cD  
    Wend ,|A6l?iV  
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    'Set new z-shift 63J3NwFt  
    op.Type = "ShiftZ" ID`Ot{ y  
    op.val1 = tlens h Ypj  
    op.parent = parID 0|J9Btbp  
    AddOperation eID, op ~JNE]mg  
    Print "Set lens thickness = " & tlens M$.bC0}T  
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    '************************************************************************* lNf);!}SM  
    'Lens index of refraction 7)[2Ud8  
    '************************************************************************* H }]Zp  
    eID = FindMaterial( "Lens" ) S7WHOr9XMV  
    GetModelMaterial eID, mat }st~$JsV1  
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    mat.Nd = nlens mdyl;e{0  
    SetModelMaterial eID, mat >N2kWSa  
    Print "Set lens index of refraction = " & nlens Fx}v.A5  
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    '************************************************************************* X lItg\R  
    'Pupil diameter G_5{5Ar  
    '************************************************************************* H\n6t-l  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) vea{o35!  
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    'Adjust pupil diameter (trimming volume inner hole) 38
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" 8{!|` b'f  
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    ' Adjust pupil location to just in front of the lens pbDr:kBL  
    parID = FindFullName( "Geometry.Arizona Eye" ) 5Za<]qxr  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) <}A6 )=T  
    count = 0 =,q/FY:  
    While GetOperationCount(eID)>count pfIK9>i  
        GetOperation eID, count, op ks("( nU  
        If op.Type="ShiftZ" Then )m3emMO2  
            DeleteOperation eID,count eY`9J4o'  
            count=count-1 A^+kA)8  
        End If sC[#R.eq  
        count=count+1 ?Fa$lE4  
    Wend W`JI/  
    op.Type = "ShiftZ" c^'bf_~-W  
    op.val1 = taq-0.01 Ye4 &4t  
    op.parent = parID .sQV0jF{  
    AddOperation eID, op ==?%
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    Print "Set pupil diameter = " & pupilDiam c(vi,U-hC  
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    'Update AZ Eye subassembly Description yK"\~t[@X:  
    eID = FindFullName( "Geometry.Arizona Eye" ) fKFD>u0%  
    GetEntity eID, entity LgX2KU"  
    entity.Description = "Accommodation = " & A & "D" L\"wz scn  
    SetEntity eID, entity |oSt%lQ1  
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    Update W{!5}Sh
 
    Print "DONE!" S1)g\Lv  
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End Sub RrrlfFms  
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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： % q!i  
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Accommodation = 4 Diopters IcQpbF0  
Pupil Diameter = 4 mm *P7n YjG  
Set aqueous humor thickness = 2.81 n} !')r  
Set anterior lens radius = 10.4 and conic constant = -2.375869 {yT<22Fl  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 ?P9VdS1-  
Set lens thickness = 3.927 J0e
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Set lens index of refraction = 1.42672 DwFvM0O6\  
Set pupil diameter = 4 N;P
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DONE! _C1u}1hW#  
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