[转载]FRED运用：Arizona眼睛模型 [复制链接]

简介 dzbFUDJ  
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。 lZ*V.-D^
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模型 WSsX*L  
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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。 (teK0s;t5k  
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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. Zk+c9,q  
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光源 k .#I
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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。 ,]LsX"u  
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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。 PNp-/1Cx  
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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%fcp  
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视网膜的散射 4>NmJrh  
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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。 `gX$N1(  
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注意在视网膜的表面有散射重点采样规格定义，在“Scatter”标签的底部可获取该信息。“toward pupil”指定散射光朝向光瞳，半角度10度。 ~vscATQ  
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脚本 "KKw\
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内置脚本使用对话框显示屈光度和光瞳直径的数值设置。使用FRED Basic脚本创建和使用对话框非常容易。图6显示了如何获取用户自定义对话框，如下图所示： .L8g(F(=:  
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如果“OK”按钮按下，将会核对对话框下面的代码行，如果点击取消则脚本终止。然后输入的参数赋予变量，如果此处是保留为空白，则使用默认值。因此，如果没有值输入并点击“OK”按钮，则脚本是以屈光度为0，光瞳直径为4mm来运行的。 &Vy.)0  
余下的脚本计算与屈光度有关的所有参数。 _-:C
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分析 giHWC%/  
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屈光度为4，光瞳直径为4mm，字母F点在视网膜上所成的像。 \q
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脚本代码 dfMi]rs!<  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. Nz%Yi?AF  
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Dim entity As T_ENTITY 7{Zs"d{s  
Dim op As T_OPERATION hiw>Q7W  
Dim mat As T_MODELMATERIAL ;$g?W"  
Dim A As Double &W{<Yf9  
Dim pupilDiam As Double #]*]qdQWV^  
Dim eID As Long XaH;  
Dim parID As Long a49t/  
Dim count As Integer Vtv1{/@+c  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double t[p/65L>8  
Dim tlens As Double, nlens As Double w^^8*b<  
Dim curv As Double, conic As Double IqCh4y3  
Dim ok As Long Ns$,.D  
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Sub Main Wrf+5 ;,,  
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    '用户输入对话框 5Bp>*MR/".  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 |&
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        TextBox 220,21,40,21,.TextBox1 'default: 0 |w.h97fj  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 |4!G@-2V:I  
        OKButton 40,91,90,21 N6BEl55 &  
        CancelButton 190,91,90,21 c!a1@G  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 w"q^8"j!  
        TextBox 220,49,40,21,.TextBox2 'default: 4 KT0Pmpp
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    End Dialog C1x(4&h  
    Dim dlg As UserDialog ~_|CXPiQ8  
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    ok = Dialog (dlg) br')%f}m  
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    If ok=0 Then    'cancel button was pressed [sl"\3)  
        Print "Execution cancelled." =%d.wH?dZ/  
        End sMcN[r  
    End If rw#?NI:  
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    'Assign accommodation and pupil diameter & use defaults if field left empty {yM@3v~  
    If dlg.TextBox1 = "" Then -/R?D1kOq  
        A = 0           'Default accommodation N~%~Q  
    Else >/'/^h  
        A = CDbl(dlg.TextBox1) bd&Nf2  
    End If VgO.in^q  
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    If dlg.TextBox2 = "" Then hR,5U=+M7  
        pupilDiam = 4   'Default pupil diameter I\f\k>;  
    Else gT2k}5d}p  
        pupilDiam = CDbl(dlg.TextBox2) c@lH  
    End If r85j/YK  
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    Print " " $AHdjQ[;6-  
    Print "Accommodation = " & A & " Diopters" V U
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    Print "Pupil Diameter = " & pupilDiam & " mm" PoZxT-U  
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    ' Calculate new parameters with accommodation ;FnS=Z  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness Hm]\.ZEy  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens ?I7%u
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    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens .50ql[En  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens 2U) 0k*  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens ASa)xf9  
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    tlens = 3.767 + 0.04*A                  'Lens thickness
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction 1SG^X-(GM/  
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    'Adjust parameters to account for accommodation m{by
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    '************************************************************************* uHPd!#]  
    'Aqueous thickness (Position of Lens) ft?c&h;At  
    '************************************************************************* !JbWxGN`jn  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) V L;<+C~  
    GetCustomElement eID, entity [{6fyd;  
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    parID = FindFullName( "Geometry.Arizona Eye" ) ._6e#=  
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    ' Delete any shift(s) in z .QB)Y* z  
    count = 0 KVPWJHGr
 
    While GetOperationCount(eID)>count c>BDw<  
        GetOperation eID, count, op lMe+.P|  
        If op.Type="ShiftZ" Then S&NWZ:E3[  
            DeleteOperation eID,count @cn8m  
            count=count-1 7Jn%c<s  
        End If {tUxRX  
        count=count+1 z7R2viR[  
    Wend qb+Gjgp  
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    'Set new shift in 7,FhKTV1/  
    op.Type = "ShiftZ" `( _N9.>B  
    op.val1 = taq =}2k+v-B  
    op.parent = parID _c,{}sn  
    AddOperation eID, op )^m"fQ+  
    Print "Set aqueous humor thickness = " & taq-0.55 nc;iJ/\4  
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    '************************************************************************* cnj32H^+  
    'Radius and conic constant of anterior lens /#!
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    '************************************************************************* CwwZ~2  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) 0}WDB_L  
    GetConic eID, entity, curv, conic FLLfTkXdI  
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    SetConic eID, entity, 1/Rant, CCant h/..cVD,K  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant H.&"
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    '************************************************************************* L+_ JKc  
    'Radius and conic constant of posterior lens &p5^Cjy L  
    '************************************************************************* 8j}o\!H  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) 
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    GetConic eID, entity, curv, conic \%QA)T%  
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    SetConic eID, entity, 1/Rpost, CCpost 3Hf_!C=g  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost K,dEa<p  
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    '************************************************************************* +f'@  
    'Lens thickness (Position of posterior lens surface) #aIV\G  
    '************************************************************************* drS>~lSxB  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) $~NB .SY  
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    ' Delete any z-shift(s) WMnxN34  
    count = 0 CRu {Ie5B  
    While GetOperationCount(eID)>count {}"a_L&[;  
        GetOperation eID, count, op DtkOb,wY  
        If op.Type="ShiftZ" Then EXti  
            DeleteOperation eID,count +.McC$!s  
            count=count-1 TbgIr  
        End If c=33O,_  
        count=count+1 Fz2CXC  
    Wend Gp2Cwyv  
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    'Set new z-shift I$*LMzve  
    op.Type = "ShiftZ" \ \gAa-}:  
    op.val1 = tlens E6#")2C~  
    op.parent = parID :"`1}Q  
    AddOperation eID, op '}F..w/  
    Print "Set lens thickness = " & tlens e(vnnv?R{  
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    '************************************************************************* 5Vlm?mPU  
    'Lens index of refraction fr8hT(,s)  
    '************************************************************************* ! l"*DR  
    eID = FindMaterial( "Lens" ) "s7}eWM*a  
    GetModelMaterial eID, mat aMaqlqf  
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    mat.Nd = nlens AA[?a  
    SetModelMaterial eID, mat \omfWW
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    Print "Set lens index of refraction = " & nlens <=@6UPsn2  
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    '************************************************************************* w$jq2?l  
    'Pupil diameter )u
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    '************************************************************************* ZV$!dHW/  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) yDAvl+  
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    'Adjust pupil diameter (trimming volume inner hole) C5=m~  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" S y^et  
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    ' Adjust pupil location to just in front of the lens pf#~|n#t  
    parID = FindFullName( "Geometry.Arizona Eye" ) 2D4c|R@+  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) "O8iO!:  
    count = 0 `/9&o;qM   
    While GetOperationCount(eID)>count \:E=B1  
        GetOperation eID, count, op _vUId?9@+e  
        If op.Type="ShiftZ" Then ;Ngu(es6  
            DeleteOperation eID,count ~>rnq7j  
            count=count-1 a<P?4tbF  
        End If N
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        count=count+1 9a]h;r8,9z  
    Wend 'S6JpWG1  
    op.Type = "ShiftZ" P>_ r6C  
    op.val1 = taq-0.01 cCqmrjUmV  
    op.parent = parID WTUC\}#E\  
    AddOperation eID, op IQ5'4zQg=  
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    Print "Set pupil diameter = " & pupilDiam {r:5\  
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    'Update AZ Eye subassembly Description ?F9c6$|  
    eID = FindFullName( "Geometry.Arizona Eye" ) N`+@_.iBX  
    GetEntity eID, entity FH7l6b,^  
    entity.Description = "Accommodation = " & A & "D" `]5t'Ps  
    SetEntity eID, entity p`}G"DM  
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    Update _p0G8  
    Print "DONE!" Mi7LyIu  
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End Sub `ex>q  
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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： >!%+)  
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Accommodation = 4 Diopters j "e]Ui  
Pupil Diameter = 4 mm q!<n\X3]u  
Set aqueous humor thickness = 2.81 6dKJt  
Set anterior lens radius = 10.4 and conic constant = -2.375869 DVw 04ay%  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 yXCJ?  
Set lens thickness = 3.927 2(2
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Set lens index of refraction = 1.42672 g.COKA  
Set pupil diameter = 4 Ev,b5KelD  
DONE! tWA<OOl  
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