[转载]FRED运用：Arizona眼睛模型 [复制链接]

简介 D\^WXY5e%y  
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。 69kJC/1+l  
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模型 NYABmI/0c  
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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。 5&CDHc7Oj  
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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. P&*sB%B  
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光源 W[NEe,.>  
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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。 r^HAaGpC  
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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。 e=/&(
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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。 v| z08\a[  
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视网膜的散射 XeUC0K[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。 ~3
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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。 Q^eJ4{Ya:  
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脚本 XOb}<y)r~  
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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： (N~$x  
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如果“OK”按钮按下，将会核对对话框下面的代码行，如果点击取消则脚本终止。然后输入的参数赋予变量，如果此处是保留为空白，则使用默认值。因此，如果没有值输入并点击“OK”按钮，则脚本是以屈光度为0，光瞳直径为4mm来运行的。 96|[}:+$&:  
余下的脚本计算与屈光度有关的所有参数。 +6W(z3($  
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分析 p{;i& HNdp  
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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。 K <`>O, F  
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脚本代码 T|'&K:[TJ  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. -
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Dim entity As T_ENTITY y62%26 [  
Dim op As T_OPERATION sy<iKCM\  
Dim mat As T_MODELMATERIAL lxb
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Dim A As Double 2wh#$zGy  
Dim pupilDiam As Double XQ;I,\m  
Dim eID As Long H/cTJ9zz  
Dim parID As Long E'dX)J9e$/  
Dim count As Integer (6xDu.u?A  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double :\}U9QfCw  
Dim tlens As Double, nlens As Double L`K;IV%;  
Dim curv As Double, conic As Double Ky9W/dCR  
Dim ok As Long we]>(|  
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Sub Main tEhr  
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    '用户输入对话框 Y)p4]>lT+8  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 r+gjc?Ol  
        TextBox 220,21,40,21,.TextBox1 'default: 0 Lar r}o=  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 lmFA&s"m  
        OKButton 40,91,90,21 9D4-^M:a  
        CancelButton 190,91,90,21 E/O5e(h  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 pt!'v$G/*  
        TextBox 220,49,40,21,.TextBox2 'default: 4 _PB@kH#  
    End Dialog X8 qIia  
    Dim dlg As UserDialog Cd~LsdKE5  
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    ok = Dialog (dlg) }:#dV B+  
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    If ok=0 Then    'cancel button was pressed P/aDd@j  
        Print "Execution cancelled." %8D?$v"#Z  
        End zl)&U=
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    End If X4I]9t\  
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    'Assign accommodation and pupil diameter & use defaults if field left empty ;QPy:x3  
    If dlg.TextBox1 = "" Then .
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        A = 0           'Default accommodation Vipp /WV  
    Else ?`. XK}  
        A = CDbl(dlg.TextBox1) v ($L  
    End If >h7$v~nra  
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    If dlg.TextBox2 = "" Then xwLy|&  
        pupilDiam = 4   'Default pupil diameter 5P\N"Yjx'  
    Else wgZrrq/W|  
        pupilDiam = CDbl(dlg.TextBox2) Mo|yv[(K,  
    End If )0|):g  
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    Print " " J#@l
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    Print "Accommodation = " & A & " Diopters" "_)|8|gN  
    Print "Pupil Diameter = " & pupilDiam & " mm" RZ6~c{  
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    ' Calculate new parameters with accommodation u+DX$#-n!]  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness >Z"9rF2SW  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens 3Uo]>BG  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens {Q<0\`A  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens 'z](xG<  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens 1PIzV:L\  
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    tlens = 3.767 + 0.04*A                  'Lens thickness ?Ccw4]YO,=  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction A^vvST%7  
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    'Adjust parameters to account for accommodation {Y"8~  
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    '************************************************************************* jJ-d/"(  
    'Aqueous thickness (Position of Lens) S
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    '************************************************************************* `U#Po_hq  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) %O_t`wz  
    GetCustomElement eID, entity vnVZJ}]w\  
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    parID = FindFullName( "Geometry.Arizona Eye" ) V^vLN[8_\  
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    ' Delete any shift(s) in z tx)OJ

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    count = 0 w5Z2N[hy  
    While GetOperationCount(eID)>count PC0HH  
        GetOperation eID, count, op N*':U^/t4J  
        If op.Type="ShiftZ" Then Un\Ubqi0  
            DeleteOperation eID,count i :EO(`  
            count=count-1 Ff&R0v  
        End If t.L4%1OF  
        count=count+1 IadK@?X6j  
    Wend j`hNZ%a  
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    'Set new shift in zM\IKo_"  
    op.Type = "ShiftZ" <L2GUX36#
 
    op.val1 = taq *LEu=3lp%>  
    op.parent = parID D2Vv\f  
    AddOperation eID, op q /:T1a7!  
    Print "Set aqueous humor thickness = " & taq-0.55 ]p\u$VY9  
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    '************************************************************************* hw|t8 ShW  
    'Radius and conic constant of anterior lens gu!](yEgl  
    '************************************************************************* XUf7yD  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) S_j1=6#^  
    GetConic eID, entity, curv, conic F/xCG nP-  
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    SetConic eID, entity, 1/Rant, CCant 7\f{'KL  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant _Ws#UL+Nq  
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    '************************************************************************* K,G,di  
    'Radius and conic constant of posterior lens f%L:<4  
    '************************************************************************* a" ^#!G<+  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) QYH."7X >  
    GetConic eID, entity, curv, conic  u*U_7Uw$  
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    SetConic eID, entity, 1/Rpost, CCpost '1Y<RD>x  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost k+f1sV[4}  
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    '************************************************************************* ZRX^^yN  
    'Lens thickness (Position of posterior lens surface) $vW^n4!  
    '************************************************************************* {uEu>D$8  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) (I>HWRH  
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    ' Delete any z-shift(s) >,kL p|gA  
    count = 0 3>H2xh3Y  
    While GetOperationCount(eID)>count <|B$dz?r  
        GetOperation eID, count, op {qY3L8b  
        If op.Type="ShiftZ" Then ?U}sQ;c$  
            DeleteOperation eID,count %Fs*
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            count=count-1 V/@[%w=  
        End If ;A x=]Q  
        count=count+1 -<]\l3E&J  
    Wend VtD@&N  
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    'Set new z-shift q|R+x7x  
    op.Type = "ShiftZ" Nz3zsP$  
    op.val1 = tlens KSF5)CZ5  
    op.parent = parID F19;RaP+  
    AddOperation eID, op "L ^TT2  
    Print "Set lens thickness = " & tlens t) ;   

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    '************************************************************************* 6.k^m&-A  
    'Lens index of refraction 9cl{hdP{  
    '************************************************************************* f&=K]:WDe  
    eID = FindMaterial( "Lens" ) v!nm &"  
    GetModelMaterial eID, mat qK<aZ%V  
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    mat.Nd = nlens rat=)n)"t  
    SetModelMaterial eID, mat
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    Print "Set lens index of refraction = " & nlens JJ^iy*v  
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    '************************************************************************* C<zx'lw!  
    'Pupil diameter 9"m,p  
    '************************************************************************* >&*6Fqd  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) Ti0 (VdY  
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    'Adjust pupil diameter (trimming volume inner hole) tVC@6Z$  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" 3FGbQ_  
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    ' Adjust pupil location to just in front of the lens 8yY"x ['  
    parID = FindFullName( "Geometry.Arizona Eye" ) B)(p9]q  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) j:3A;r\  
    count = 0 R tXF  
    While GetOperationCount(eID)>count L-^# 02  
        GetOperation eID, count, op k/$Ja;  
        If op.Type="ShiftZ" Then Rh wt<  
            DeleteOperation eID,count "
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            count=count-1 4U}.Skzq  
        End If n,CD4Nv  
        count=count+1 jrDz7AfA  
    Wend daaga}]d  
    op.Type = "ShiftZ" ^4n2 -DvG  
    op.val1 = taq-0.01 dbf^A1HI  
    op.parent = parID + TPbIRA  
    AddOperation eID, op eyI-s9#t  
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    Print "Set pupil diameter = " & pupilDiam |HKHN?)  
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    'Update AZ Eye subassembly Description V Z4nAG  
    eID = FindFullName( "Geometry.Arizona Eye" ) YHwVj?6W  
    GetEntity eID, entity >=Rd3dgDG  
    entity.Description = "Accommodation = " & A & "D" ?^e*UJNM  
    SetEntity eID, entity (E2lv#[  
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    Update :X1`wBu  
    Print "DONE!" DzX6U[=  
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End Sub Zq2H9^![y~  
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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： $6Q2)^LJ  
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Accommodation = 4 Diopters UgOGBj,&5W  
Pupil Diameter = 4 mm $G^H7|PzdC  
Set aqueous humor thickness = 2.81 f_z2#,g  
Set anterior lens radius = 10.4 and conic constant = -2.375869 ]ly)z[is"]  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 s5_1}KKCs  
Set lens thickness = 3.927 K284R=j -&  
Set lens index of refraction = 1.42672 ss|6_H =  
Set pupil diameter = 4 OI;L9\MJc  
DONE! K4K3<Pg  
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