[转载]FRED运用：Arizona眼睛模型 [复制链接]

简介 QX(:!b  
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。 8KoPaq  
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模型 IHagRldG  
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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。 )XO2DY1/&  
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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. (x=NA )  
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光源 5jjJQ'  
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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。 ?on3z  
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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。 * rs_k/2(  
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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。 `C!Pe84(  
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视网膜的散射 u8[X\f  
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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。 {ZfTUt)-P  
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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。 Vx#xq#wK  
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脚本 7`WK1_rR\  
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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： a>Q7Qn  
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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。 ^|gN?:fA}  
余下的脚本计算与屈光度有关的所有参数。 4`*jF'N[  
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分析 wPG3Ap8L  
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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。 8"S0E(,mu  
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脚本代码 #~ >0Dr  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. w\\   
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Dim entity As T_ENTITY ]*v%(IGK  
Dim op As T_OPERATION %_/_klxnO  
Dim mat As T_MODELMATERIAL |:EUh  
Dim A As Double X#Hs{J~@p  
Dim pupilDiam As Double $%!]tNGS  
Dim eID As Long 2j_L jY'7  
Dim parID As Long z1YC%Y|R  
Dim count As Integer ZB%7Sr0  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double p_mP'
  
Dim tlens As Double, nlens As Double cZHlW|$R  
Dim curv As Double, conic As Double GadD*psD2  
Dim ok As Long KWd]?e)  
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Sub Main EW YpYMkm  
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    '用户输入对话框 WMYvE\"  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 3:76x
 
        TextBox 220,21,40,21,.TextBox1 'default: 0 DuCq16'0T  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 ==Y^~ab;K  
        OKButton 40,91,90,21 rVZkG,Q  
        CancelButton 190,91,90,21 &}*[-z  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 ^IC|3sr   
        TextBox 220,49,40,21,.TextBox2 'default: 4 m@TU2  
    End Dialog !$&K~>`  
    Dim dlg As UserDialog @mw1(J  
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    ok = Dialog (dlg) AC 3 ;i  
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    If ok=0 Then    'cancel button was pressed h( Iti&  
        Print "Execution cancelled." MF>?! !  
        End G0<m3 Up  
    End If cp]\<p('A  
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    'Assign accommodation and pupil diameter & use defaults if field left empty EXo"F*gW  
    If dlg.TextBox1 = "" Then k}JjSt1_A;  
        A = 0           'Default accommodation &Tl3\T0D  
    Else _jP]ifu`  
        A = CDbl(dlg.TextBox1) _d,_&
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    End If (?oK+,v?L  
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    If dlg.TextBox2 = "" Then hfVJg7-  
        pupilDiam = 4   'Default pupil diameter Pq !\6s@  
    Else 'Kc;~a  
        pupilDiam = CDbl(dlg.TextBox2) ^|OxlfS  
    End If (i&:=Bfn)  
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    Print " " @7.Ews5Mke  
    Print "Accommodation = " & A & " Diopters" 0riTav8  
    Print "Pupil Diameter = " & pupilDiam & " mm" n{=vP`V_  
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    ' Calculate new parameters with accommodation o5A@U0c_  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness | [P!9e  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens ;5dJ5_}  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens PWmFY'=  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens ZC@Pfba[`  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens ,n^{!^JW  
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    tlens = 3.767 + 0.04*A                  'Lens thickness r ",..{  

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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction }cEcoi<v!  
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    'Adjust parameters to account for accommodation <Y9e n!3\  
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    '************************************************************************* i=nd][1n  
    'Aqueous thickness (Position of Lens) 6||zfH  
    '************************************************************************* Z`T]jm-3  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) ? 0
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    GetCustomElement eID, entity &M&*3  
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    parID = FindFullName( "Geometry.Arizona Eye" ) \0). ODA(  
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    ' Delete any shift(s) in z ~5q1zr)E  
    count = 0 WBK6U
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    While GetOperationCount(eID)>count <
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        GetOperation eID, count, op P XKEqcQR  
        If op.Type="ShiftZ" Then ~l+2Z4nV  
            DeleteOperation eID,count _ VKBzOH  
            count=count-1 Uc^eIa@  
        End If A+de;&  
        count=count+1 g]vo."}5E  
    Wend Je5}Z.3m  
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    'Set new shift in m}hEi  
    op.Type = "ShiftZ" OD]`oJ|  
    op.val1 = taq < KGq  
    op.parent = parID +saXN6  
    AddOperation eID, op N?`V;`[  
    Print "Set aqueous humor thickness = " & taq-0.55 1-0tG+  
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    '************************************************************************* ( RO-~-  
    'Radius and conic constant of anterior lens +fS<YT  
    '************************************************************************* z?dd5.k  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) GZH{"_$  
    GetConic eID, entity, curv, conic hz:h>Hwy  
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    SetConic eID, entity, 1/Rant, CCant sPX&XqWx  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant %|j`z
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    '************************************************************************* Znr@-=xZO*  
    'Radius and conic constant of posterior lens v|\3FEu@  
    '************************************************************************* ~-R%m  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) cX7 O*5C  
    GetConic eID, entity, curv, conic ];xDXQd  
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    SetConic eID, entity, 1/Rpost, CCpost |;:g7eb  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost d|?Xo\+  
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    '************************************************************************* Ps!umV  
    'Lens thickness (Position of posterior lens surface) $vrkxn  
    '************************************************************************* E75/EQ5p]p  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) L4,b
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    ' Delete any z-shift(s) ijsoY\V50  
    count = 0 @A4$k dJ2  
    While GetOperationCount(eID)>count .7]P-]uOZ  
        GetOperation eID, count, op 3xT9/8*  
        If op.Type="ShiftZ" Then b9-IrR4h  
            DeleteOperation eID,count 28k=@k^q  
            count=count-1 T/a=z  
        End If 8~tX>q<@q  
        count=count+1 2n)?)w]!M  
    Wend KL3Z(  
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    'Set new z-shift C];P yQS  
    op.Type = "ShiftZ" v3#,Z!  
    op.val1 = tlens oNZ_7tU  
    op.parent = parID yQuL[#
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    AddOperation eID, op N_IKH)  
    Print "Set lens thickness = " & tlens  D|)a7_  
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    '************************************************************************* Fvf|m7  
    'Lens index of refraction f(Y_<%  
    '************************************************************************* N0H=;CIQ  
    eID = FindMaterial( "Lens" ) 2]1u0-M5L  
    GetModelMaterial eID, mat 1rJ2}d\y  
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    mat.Nd = nlens CHsg2S  
    SetModelMaterial eID, mat o:D,,Mk
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    Print "Set lens index of refraction = " & nlens V:$+$"|  
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    '************************************************************************* B2e"  
    'Pupil diameter T5 (|{-  
    '************************************************************************* CJ* D  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) HcgvlFb  
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    'Adjust pupil diameter (trimming volume inner hole) >~SS^I0  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" TG%B:^Yz!  
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    ' Adjust pupil location to just in front of the lens #L~i|(=U5  
    parID = FindFullName( "Geometry.Arizona Eye" ) U}LW8886  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) |@vkQ  
    count = 0 b~J)LXj]w  
    While GetOperationCount(eID)>count d=/0A\O  
        GetOperation eID, count, op lG}#K^q  
        If op.Type="ShiftZ" Then N7?B"p/  
            DeleteOperation eID,count J#zr50@@  
            count=count-1 z5kAf~A  
        End If 1@DC#2hPr  
        count=count+1 uMJ\  
    Wend 6RnzT d  
    op.Type = "ShiftZ" ;f=m+QXU  
    op.val1 = taq-0.01 Y !?'[t  
    op.parent = parID L=l&,ENy  
    AddOperation eID, op Qc; kj  

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    Print "Set pupil diameter = " & pupilDiam _y@].G  
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    'Update AZ Eye subassembly Description %GHGd'KO&  
    eID = FindFullName( "Geometry.Arizona Eye" ) J;C:nE|V  
    GetEntity eID, entity 1^!SuAA@  
    entity.Description = "Accommodation = " & A & "D" ;V xRaj?  
    SetEntity eID, entity /|IPBU 5  
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    Update xT%`"eM}  
    Print "DONE!" x4oWZEd  
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End Sub uu9M}]mDl  
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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*@sa]  
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Accommodation = 4 Diopters ,#K/+T  
Pupil Diameter = 4 mm 0cd_l 2f#g  
Set aqueous humor thickness = 2.81 Zh=arlk  
Set anterior lens radius = 10.4 and conic constant = -2.375869 ^[M{s(b  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 7?$?Yu  
Set lens thickness = 3.927 \$ytmtf5  
Set lens index of refraction = 1.42672 F5h/>  
Set pupil diameter = 4 i[v4[C=WB!  
DONE! 54gr'qvr  
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