[转载]FRED运用：Arizona眼睛模型 [复制链接]

简介 >~8Df61o`  
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。 QX3![;0F  
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模型 r:Tb{cA  
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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。 W3j|%  
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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. eBKIdR%k  
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光源 c324@o^V  
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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。 }iloX#  
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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。 +# >%bq x  
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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。 T#f@8 -XUE  
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视网膜的散射 QYGxr+D  
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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。 JOq<lb=  
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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。 3%a37/|~y  
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脚本 c[7qnSH  
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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)`vc#"65k  
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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。 A6L}5#7-  
余下的脚本计算与屈光度有关的所有参数。 (Mh\!rMg  
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分析 z+I-3v  
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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。 b2%[9)"I.  
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脚本代码 uy{KV"%"^g  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. $)~]4n
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Dim entity As T_ENTITY XQ+hTtP  
Dim op As T_OPERATION d:''qgz`  
Dim mat As T_MODELMATERIAL n9Yk;D2  
Dim A As Double '3->G/Pu  
Dim pupilDiam As Double 5?MvO]_  
Dim eID As Long 1gJ!!SHPo  
Dim parID As Long Mw.+0R!T  
Dim count As Integer GAlO<Mu
  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double O
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Dim tlens As Double, nlens As Double ZP<X#]$qb  
Dim curv As Double, conic As Double HfiM]^  
Dim ok As Long i=T/}c)  
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Sub Main U\{Z{F%8  
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    '用户输入对话框 -(G2@NG  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 B!v1gh  
        TextBox 220,21,40,21,.TextBox1 'default: 0 L\[jafb_`  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 MC@cT^Z^  
        OKButton 40,91,90,21 zZHsS$/  
        CancelButton 190,91,90,21 |T%/d#b~  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 +h/$_5  
        TextBox 220,49,40,21,.TextBox2 'default: 4 o_n.,=/cZ  
    End Dialog ]Y?$[+Y  
    Dim dlg As UserDialog (I5ra_FVs  
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    ok = Dialog (dlg) 5UbVg  
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    If ok=0 Then    'cancel button was pressed `ijX9c  
        Print "Execution cancelled." ($TxVFNT  
        End :xV&%Qa1  
    End If 4$"Lf'sH6  
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    'Assign accommodation and pupil diameter & use defaults if field left empty |7-tUHMo[  
    If dlg.TextBox1 = "" Then s7?kU3y=s  
        A = 0           'Default accommodation k*Kq:$9"  
    Else :EjIV]e  
        A = CDbl(dlg.TextBox1) hbK+\X  
    End If THJ+OnP  
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    If dlg.TextBox2 = "" Then 5a/)
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        pupilDiam = 4   'Default pupil diameter QI-3mqL  
    Else l O^h)hrR  
        pupilDiam = CDbl(dlg.TextBox2) s"/8h#!zv  
    End If m[pzu2R  
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    Print " " i/L1KiCLx  
    Print "Accommodation = " & A & " Diopters" ^=ikxZyO  
    Print "Pupil Diameter = " & pupilDiam & " mm" ){}#v&  
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    ' Calculate new parameters with accommodation /d4xHt5a  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness 4$^=1ax  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens [Dhc9  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens U uysG\  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens SXL6)pX  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens K^S#?T|[9  
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    tlens = 3.767 + 0.04*A                  'Lens thickness f { ueI<  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction |z~?"F6 Y<  
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    'Adjust parameters to account for accommodation NXx}KF c  
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    '************************************************************************* t^'1Ebg  
    'Aqueous thickness (Position of Lens) dw-r}Qioe  
    '************************************************************************* mKg~8q 3  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) X DX_c@U  
    GetCustomElement eID, entity e:l 6;  
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    parID = FindFullName( "Geometry.Arizona Eye" ) %>.v[d1c  
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    ' Delete any shift(s) in z ;kbz(:wA  
    count = 0 ZFzOW  
    While GetOperationCount(eID)>count DXUI/C f  
        GetOperation eID, count, op P(4[<'HO  
        If op.Type="ShiftZ" Then |] YT6-?.  
            DeleteOperation eID,count fq(e~Aqw$  
            count=count-1 "$)2|  
        End If T:ck/:ZH  
        count=count+1 q8
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    Wend | @YN\g K;  
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    'Set new shift in B}(YD;7vJ  
    op.Type = "ShiftZ" CtfSfSAUuu  
    op.val1 = taq Xy{b(b;9  
    op.parent = parID =4I361oMf  
    AddOperation eID, op =$'Zmb [D  
    Print "Set aqueous humor thickness = " & taq-0.55 kC+A7k6  
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    '************************************************************************* :J"e{|g',  
    'Radius and conic constant of anterior lens Zy#r<j]T  
    '************************************************************************* t@Jo ?0s  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) \yxr@z1_b  
    GetConic eID, entity, curv, conic :K&hGZ+5  
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    SetConic eID, entity, 1/Rant, CCant N>~*Jp2;  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant "mOoGy,(  
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    '************************************************************************* t.w?OyO  
    'Radius and conic constant of posterior lens ^R\blJQ<^  
    '************************************************************************* A=])pYE1  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) QdRMp n}q  
    GetConic eID, entity, curv, conic cqq+#39iC  
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    SetConic eID, entity, 1/Rpost, CCpost 48DsRy  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost 5 9X|l&/  
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    '************************************************************************* m/ukH{H1%  
    'Lens thickness (Position of posterior lens surface) 6y0C  
    '************************************************************************* (lm/S_U$  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) OJK/>  
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    ' Delete any z-shift(s) $~-j-0 \m  
    count = 0 uZ^i8;i  
    While GetOperationCount(eID)>count *Dn{MD7,M  
        GetOperation eID, count, op u-W=~EO5#  
        If op.Type="ShiftZ" Then tEeMl =u  
            DeleteOperation eID,count \uaJw\EZ  
            count=count-1 ^?A+`1-  
        End If ~% c->\Q  
        count=count+1 U".-C`4v  
    Wend *vb)
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    'Set new z-shift e`oc#Od&x]  
    op.Type = "ShiftZ" NX;&V7  
    op.val1 = tlens 83h3C EQ  
    op.parent = parID oHYD6qJX{  
    AddOperation eID, op vuAjAeKm  
    Print "Set lens thickness = " & tlens HfF$>Z'kM  
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    '************************************************************************* YU`{  
    'Lens index of refraction IlrmXSr  
    '************************************************************************* pGFocw  
    eID = FindMaterial( "Lens" ) 9+:Trc\%N
 
    GetModelMaterial eID, mat \,Ndg*qC  
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    mat.Nd = nlens _e'mG'P(  
    SetModelMaterial eID, mat L:<'TXsRA  
    Print "Set lens index of refraction = " & nlens [>0r'-kI  
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    '************************************************************************* $d"+Njd  
    'Pupil diameter v^tKT&  
    '************************************************************************* h2>0#Vp3j  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) /p>[$`Aq  
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    'Adjust pupil diameter (trimming volume inner hole) _X[c19q  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" Jj " {r{  
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    ' Adjust pupil location to just in front of the lens BP6Shc|C  
    parID = FindFullName( "Geometry.Arizona Eye" ) b~gF,^w  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) msylb~^  
    count = 0 Zux2VepT  
    While GetOperationCount(eID)>count @-}]~|<  
        GetOperation eID, count, op E`|qFG<  
        If op.Type="ShiftZ" Then ZTZE_[  
            DeleteOperation eID,count m!_ghD{5h  
            count=count-1 ks D1NB;9  
        End If LnGSYrx1  
        count=count+1 "puz-W'n  
    Wend I>aa'em  
    op.Type = "ShiftZ" Mk[`HEO  
    op.val1 = taq-0.01 @{uc  
    op.parent = parID *q{UipZbx  
    AddOperation eID, op =6&D4~R  
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    Print "Set pupil diameter = " & pupilDiam 7g9^Jn  
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    'Update AZ Eye subassembly Description 9 NQq=@  
    eID = FindFullName( "Geometry.Arizona Eye" ) S!_?# ^t  
    GetEntity eID, entity TzGm562o%  
    entity.Description = "Accommodation = " & A & "D" (_ah~VnO  
    SetEntity eID, entity o"[bIXf-h  
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    Update 6/ipdi[ _  
    Print "DONE!" ()?co<@(l  
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End Sub -FV'%X$i  
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如果屈光度是4，光瞳直径是4，则会输出如下数据： ]xEE7H]\h  
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Accommodation = 4 Diopters N'P,QiR,z<  
Pupil Diameter = 4 mm }TJ|d=  
Set aqueous humor thickness = 2.81 u7Y< ~  
Set anterior lens radius = 10.4 and conic constant = -2.375869 +|)1_NK  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 NqE7[wH  
Set lens thickness = 3.927 <Cu?$  
Set lens index of refraction = 1.42672 Ks2%F&\cE  
Set pupil diameter = 4 b.q"
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DONE! T,2Dr;  
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