[转载]FRED运用：Arizona眼睛模型 [复制链接]

简介 'YvRkWf:KC  
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。 ZxB7H{  
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模型 Ctx`b[&KXX  
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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。 YY4q99^K  
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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. Ajm4q_
  
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光源 {I8C&GS  
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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。 Zo<j"FG  
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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。 ~L4L|q 7  
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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。 w
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视网膜的散射 $`[TIyA9!  
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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。 -B& Nou
 
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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。 xqb*;TBh*  
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脚本 =~>g--^U  
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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： U$46=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。 V8Ri2&|3  
余下的脚本计算与屈光度有关的所有参数。 6{quO#!  
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分析 cn Ohj  
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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。 adPd}rt;  
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脚本代码 e/&^~ $h  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. _u]%K-_  
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Dim entity As T_ENTITY 4fL`.n1^  
Dim op As T_OPERATION v-BQ>-&
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Dim mat As T_MODELMATERIAL A"z9t#dv@  
Dim A As Double >g m  
Dim pupilDiam As Double lQd7p+21  
Dim eID As Long Nv^byWqu  
Dim parID As Long :a^/&LbLm  
Dim count As Integer o{hX?,4i  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double Au6Y]  
Dim tlens As Double, nlens As Double SF`(`h0e  
Dim curv As Double, conic As Double +~~2OUL  
Dim ok As Long }*C*!?p
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Sub Main p{}4#+-<#H  
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    '用户输入对话框 ~Hu!iZ2]  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 YN+vk}8 <  
        TextBox 220,21,40,21,.TextBox1 'default: 0 Z/dhp0k  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 p!5'#\^f  
        OKButton 40,91,90,21 yRIXUCy  
        CancelButton 190,91,90,21 e,&#,O  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 lB0`|UEb (  
        TextBox 220,49,40,21,.TextBox2 'default: 4 ^,#
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    End Dialog bAbR0)  
    Dim dlg As UserDialog x|O^#X(,  
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    ok = Dialog (dlg) #y[U2s Se  
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    If ok=0 Then    'cancel button was pressed OQ- Hn-H  
        Print "Execution cancelled."
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        End 3%hq<  
    End If ZPyzx\6\  
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    'Assign accommodation and pupil diameter & use defaults if field left empty .r2*tB).  
    If dlg.TextBox1 = "" Then *yaS^k\  
        A = 0           'Default accommodation 1`YU9?  
    Else DzQ  
        A = CDbl(dlg.TextBox1) OZ+v ~'oD  
    End If TN1pg  
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    If dlg.TextBox2 = "" Then fx(h fz  
        pupilDiam = 4   'Default pupil diameter !?(7g2NP)  
    Else TS#[[^!S  
        pupilDiam = CDbl(dlg.TextBox2) _'LZf=V0  
    End If m3TR}=n  
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    Print " " __2<v?\  
    Print "Accommodation = " & A & " Diopters" h%krA<G9  
    Print "Pupil Diameter = " & pupilDiam & " mm" LP=j/qf|  
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    ' Calculate new parameters with accommodation W*t] d  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness @phVfP"M  

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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens e=WjFnK[x7  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens )@X0'X<  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens D%abBE1  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens b7Jxv7$e  
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    tlens = 3.767 + 0.04*A                  'Lens thickness w?8SQI,~X  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction )](ls@*  
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    'Adjust parameters to account for accommodation =c'4rJ$+  
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    '************************************************************************* 6e%@uB}$  
    'Aqueous thickness (Position of Lens) >%k6k1CZ  
    '************************************************************************* RqtBz3v  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) WJ25fTsG  
    GetCustomElement eID, entity du66a+@t  
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    parID = FindFullName( "Geometry.Arizona Eye" ) `8ac;b  
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    ' Delete any shift(s) in z #*'Qm
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    count = 0 S^eem_
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    While GetOperationCount(eID)>count (Jk&U8y  
        GetOperation eID, count, op AJbCC  
        If op.Type="ShiftZ" Then sD:o 2(G*  
            DeleteOperation eID,count x#J9GP.  
            count=count-1 #wI}93E  
        End If 
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        count=count+1 9{*{Ba  
    Wend #;]#NqFX  
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    'Set new shift in D%p*G5Bg3  
    op.Type = "ShiftZ" rD].=.?1  
    op.val1 = taq ,~1'L6Ri?  
    op.parent = parID R}ki%i5|  
    AddOperation eID, op *M1GVhW(+  
    Print "Set aqueous humor thickness = " & taq-0.55 eQuu\/z*H  
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    '************************************************************************* *nCA6i  
    'Radius and conic constant of anterior lens apo)cR  
    '************************************************************************* jk9f{Iu  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) 2.D2 o  
    GetConic eID, entity, curv, conic 0%ul6LvM  
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    SetConic eID, entity, 1/Rant, CCant _MBhwNBxZ  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant eV[{c %wN:  
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    '*************************************************************************  ]n!V  
    'Radius and conic constant of posterior lens T/_u;My;  
    '************************************************************************* wa"0`a:`;  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) 'D+xs}\  
    GetConic eID, entity, curv, conic ye^x>a['  
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    SetConic eID, entity, 1/Rpost, CCpost T$5wH )<  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost oY)eN?c  
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    '************************************************************************* )9YDNVo*-  
    'Lens thickness (Position of posterior lens surface) g:o/^_  
    '************************************************************************* l<v{8:,e#  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) y, l[v39  
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    ' Delete any z-shift(s) j3Od7bBS]  
    count = 0 5pCicwea#  
    While GetOperationCount(eID)>count -9b=-K.y  
        GetOperation eID, count, op _3`GZeGV  
        If op.Type="ShiftZ" Then 4uXGpsL  
            DeleteOperation eID,count $*C }iJsF  
            count=count-1 Kxsd@^E  
        End If gP%<<yl  
        count=count+1 !j6k]BgZ  
    Wend yKML{N1D  
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    'Set new z-shift e>MtDJ5  
    op.Type = "ShiftZ" Hn/t'D3  
    op.val1 = tlens j1
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    op.parent = parID q,P.)\0A  
    AddOperation eID, op +^AdD8U  
    Print "Set lens thickness = " & tlens k79OMf<v  
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    '************************************************************************* !VD$uT  
    'Lens index of refraction C*YQ{Mz(f  
    '************************************************************************* ([8*Py|  
    eID = FindMaterial( "Lens" ) w7MRuAJ4  
    GetModelMaterial eID, mat .\b.l@O<Z  
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    mat.Nd = nlens y
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    SetModelMaterial eID, mat ?p{-Yp*h  
    Print "Set lens index of refraction = " & nlens < se~wR  
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    '************************************************************************* +L09^I  
    'Pupil diameter v[$e{Dz(  
    '************************************************************************* ;~F*2)  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) (Yy#:r;U  
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    'Adjust pupil diameter (trimming volume inner hole) C6
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" ) 8xbc&
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    ' Adjust pupil location to just in front of the lens k)+{Y v*  
    parID = FindFullName( "Geometry.Arizona Eye" ) 8(? &=>@  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) g0 Q,]\~  
    count = 0 (cVIjo+::  
    While GetOperationCount(eID)>count -c>3|bo  
        GetOperation eID, count, op 4zs0+d+  
        If op.Type="ShiftZ" Then pW[TufTa  
            DeleteOperation eID,count ;1~n|IY  
            count=count-1 *L<E
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        End If E?]$Y[KJKs  
        count=count+1 e/4C` J-  
    Wend HL{aqT2  
    op.Type = "ShiftZ" Q%6zr9  
    op.val1 = taq-0.01 >_Tyzl>z  
    op.parent = parID |K.I%B  
    AddOperation eID, op ~vYF
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    Print "Set pupil diameter = " & pupilDiam %0&,_jM/9  
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    'Update AZ Eye subassembly Description @Ov}X]ELi  
    eID = FindFullName( "Geometry.Arizona Eye" ) c6b51)sQ"  
    GetEntity eID, entity I!!cA?W  
    entity.Description = "Accommodation = " & A & "D" j~bNH~3  
    SetEntity eID, entity n%WjU)<  
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    Update C#[P<=v  
    Print "DONE!" ea{zL  
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End Sub =F
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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： ~;b}_?%o  
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Accommodation = 4 Diopters #+<YFm\i  
Pupil Diameter = 4 mm n:a~=^IV  
Set aqueous humor thickness = 2.81 A#`$#CO  
Set anterior lens radius = 10.4 and conic constant = -2.375869 B|o@|zF  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 D_(NLC  
Set lens thickness = 3.927 I>8_gp\1  
Set lens index of refraction = 1.42672 $J4)z&%dr  
Set pupil diameter = 4 ;Mmu}  
DONE! gDJ} <^  
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