[转载]FRED运用：Arizona眼睛模型 [复制链接]

简介 s"wz !{G4  
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。 _UF'Cf+Y  
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模型 'HWPuWW  
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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。 w/fiNY5FZ  
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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. $A:?o?"7}  
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光源 m?1AgsBR  
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多个光源定义来分析该模型的不同特性。图1显示了所以的光源和提示信息告诉您他们可以用来做什么。 d\ Xijy  
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除了“Letter F”之外的所有光源的光线位置设定在了孔径光阑位置处，并增加了pre-propagation distance= -8。尽管光线在光瞳处创建，规定的传输方向相对于光线位置在pre-propagation distance之后。这意味着光束沿着Z轴在眼睛的前面以平行光入射，而不是在光瞳处入射。 Q>/[*(.Wd  
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在往下看是内置的脚本用来修改屈光度，使其为4（250mm），光源“Letter F”在视网膜处生成一个字母为F的图像。绿色的光线聚焦的非常好而红色和蓝色光线有一点的模糊。使用Positions Spot Diagram分析工具来观察最为合适。 ?d)eri8,  
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视网膜的散射 7(zY:9|(  
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在散射文件中，有一个名为“Retina surface”的72%的反射型朗伯散射，它为视网膜的散射提供了一个粗略的近似。为了模拟来自视网膜的散射，改变自定义元件“Eye ball” 下的视网膜的表面从“halt all” 到”Allow All”。并使几何中“plane”可追迹。 kx[h41|n  
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注意在视网膜的表面有散射重点采样规格定义，在“Scatter”标签的底部可获取该信息。“toward pupil”指定散射光朝向光瞳，半角度10度。 ]. ^e[v6  
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脚本 8.D9OpU  
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内置脚本使用对话框显示屈光度和光瞳直径的数值设置。使用FRED Basic脚本创建和使用对话框非常容易。图6显示了如何获取用户自定义对话框，如下图所示： X>rv{@KbL  
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如果“OK”按钮按下，将会核对对话框下面的代码行，如果点击取消则脚本终止。然后输入的参数赋予变量，如果此处是保留为空白，则使用默认值。因此，如果没有值输入并点击“OK”按钮，则脚本是以屈光度为0，光瞳直径为4mm来运行的。 f(*^zga,  
余下的脚本计算与屈光度有关的所有参数。 ->U9u lTC  
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分析 !\1Pu|  
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屈光度为4，光瞳直径为4mm，字母F点在视网膜上所成的像。 -$kAWP8P4  
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脚本代码 %>k$'UWzK  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. VH$hQPP5d  
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Dim entity As T_ENTITY W&0KO-}ot  
Dim op As T_OPERATION !qVnziE,,  
Dim mat As T_MODELMATERIAL [5Pin>]z  
Dim A As Double g%f6D%d)A  
Dim pupilDiam As Double .t|B6n!  
Dim eID As Long 6"Rw&3D?  
Dim parID As Long NYp46;  
Dim count As Integer JG!@(lr  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double i6D66E  
Dim tlens As Double, nlens As Double ~i/K7qZ  
Dim curv As Double, conic As Double x1R<oB|  
Dim ok As Long la[>C:8IG  
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Sub Main :B]yreg  
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    '用户输入对话框 R3%&\<a)9  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 |4|j5<5  
        TextBox 220,21,40,21,.TextBox1 'default: 0 d;O4)8>  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 YA%0{Tdxz  
        OKButton 40,91,90,21 "AUHe6Yv  
        CancelButton 190,91,90,21 T:(c/>  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 _G=k^f_  
        TextBox 220,49,40,21,.TextBox2 'default: 4 !qF t:{-h  
    End Dialog Z`Sbq{Kx  
    Dim dlg As UserDialog X[KHI1@w  
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    ok = Dialog (dlg) tEHgQto  
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    If ok=0 Then    'cancel button was pressed xC+TO  
        Print "Execution cancelled." eJwHeG  
        End |KLCO'x  
    End If j
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    'Assign accommodation and pupil diameter & use defaults if field left empty ]KE"|}B  
    If dlg.TextBox1 = "" Then +1=]93gP  
        A = 0           'Default accommodation }MXC0Z~si  
    Else %uy5la  
        A = CDbl(dlg.TextBox1) Vmf!0-  
    End If 6@; P  
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    If dlg.TextBox2 = "" Then M"
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        pupilDiam = 4   'Default pupil diameter DZE@C^0%  
    Else -oR P ZtW  
        pupilDiam = CDbl(dlg.TextBox2) 5isqBu  
    End If =/SBZLR(9  
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    Print " " qaZQ1<e  
    Print "Accommodation = " & A & " Diopters" ] g]^^  
    Print "Pupil Diameter = " & pupilDiam & " mm" EwKFT FL  
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    ' Calculate new parameters with accommodation /U5!]7&gB  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness %UokR"  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens hWD%_"yhd  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens 7/b\N
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens "';K$&,[  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens !}PZCbDhL  
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    tlens = 3.767 + 0.04*A                  'Lens thickness 'K*. ?M  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction oo2CF!Xy  
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    'Adjust parameters to account for accommodation Dlqvz|X/  
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    '************************************************************************* &ku.Q3xGs  
    'Aqueous thickness (Position of Lens) ^LAnR>mz^r  
    '************************************************************************* Ssg1p#0J  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) }NpN<C+  
    GetCustomElement eID, entity ^Cy=L]  
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    parID = FindFullName( "Geometry.Arizona Eye" ) &5d~ODO  
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    ' Delete any shift(s) in z 51-@4E2:l:  
    count = 0 92XG|CWX  
    While GetOperationCount(eID)>count Gw-y6e'|Y  
        GetOperation eID, count, op n4InZ!)
 
        If op.Type="ShiftZ" Then jT=fq'RK  
            DeleteOperation eID,count fR>"d<
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            count=count-1 Q4Z
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        End If AjD?_DPc  
        count=count+1 <%?!3 n*  
    Wend %sCG}? y  
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    'Set new shift in 10IX84  
    op.Type = "ShiftZ" *BHp?cn;F2  
    op.val1 = taq R
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    op.parent = parID QWwdtk  
    AddOperation eID, op TpcJ1*t  
    Print "Set aqueous humor thickness = " & taq-0.55 ~@mN
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    '************************************************************************* N"8'=wB  
    'Radius and conic constant of anterior lens _E2
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    '************************************************************************* # 11<=3Yj  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) L<k(stx~  
    GetConic eID, entity, curv, conic EGVS8YP>h  
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    SetConic eID, entity, 1/Rant, CCant B&m6N,  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant ~s*kuj'%+  
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    '************************************************************************* r;_*.|AH  
    'Radius and conic constant of posterior lens w@WPp0mny  
    '************************************************************************* X`28?  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) *$Y_ %}  
    GetConic eID, entity, curv, conic Ug )eyu  
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    SetConic eID, entity, 1/Rpost, CCpost W.BX6  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost <:4b4Nl  
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    '************************************************************************* ~S\,  
    'Lens thickness (Position of posterior lens surface) @,m 7%,  
    '************************************************************************* XhUVDmeUMb  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) :.u2^*<  
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    ' Delete any z-shift(s) Irui{%T  
    count = 0 .u
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    While GetOperationCount(eID)>count _Kbj?j  
        GetOperation eID, count, op gx8i|]  
        If op.Type="ShiftZ" Then QmMA]Q  
            DeleteOperation eID,count '<$*N  
            count=count-1 /ke[nr  
        End If TE:|w Xe  
        count=count+1 m48Ab`  
    Wend YJ|U|[
 
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    'Set new z-shift L+~XW'P?  
    op.Type = "ShiftZ" @z^7*#vQv  
    op.val1 = tlens /U})mdFm  
    op.parent = parID wg<t*6&'x  
    AddOperation eID, op DMOP*;Uk  
    Print "Set lens thickness = " & tlens b=5ZfhIg[  
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    '************************************************************************* GI@;76Qf  
    'Lens index of refraction WIabQ_fX  
    '************************************************************************* a$\Bt_  
    eID = FindMaterial( "Lens" ) M%WO  
    GetModelMaterial eID, mat =RAojoN  
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    mat.Nd = nlens sX-@ >%l  
    SetModelMaterial eID, mat Z/T(
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    Print "Set lens index of refraction = " & nlens I^HwXp([  
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    '************************************************************************* #lO ^PK  
    'Pupil diameter KcUR /o5K  
    '************************************************************************* virt[5w  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) vqZBDQ0  
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    'Adjust pupil diameter (trimming volume inner hole) q\-P/aN_  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" jYvl-2A'  
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    ' Adjust pupil location to just in front of the lens m>
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    parID = FindFullName( "Geometry.Arizona Eye" ) w ^?#xU1.i  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) FmFjRYA W  
    count = 0 GaV}@Q  
    While GetOperationCount(eID)>count M|Nh(kvH  
        GetOperation eID, count, op m41%?uC/  
        If op.Type="ShiftZ" Then 7dv!  
            DeleteOperation eID,count 2j#Dwa(lZQ  
            count=count-1 
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        End If o/Q|R+yXV  
        count=count+1 +z:>Nl  
    Wend rNurzag  
    op.Type = "ShiftZ" P)#h4|xZ  
    op.val1 = taq-0.01 @;x*~0GZ  
    op.parent = parID )+DDIq  
    AddOperation eID, op 97qf3^gGd  

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    Print "Set pupil diameter = " & pupilDiam o)>iHzR</  
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    'Update AZ Eye subassembly Description Nukyvse  
    eID = FindFullName( "Geometry.Arizona Eye" ) qWx{eRp d  
    GetEntity eID, entity t\}_WygN  
    entity.Description = "Accommodation = " & A & "D" b^&azUkMN  
    SetEntity eID, entity O#t[YP  
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    Update b(CO7/e>  
    Print "DONE!" axDa&7%  
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End Sub H^54o$5  
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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： 8};kNW^2m  
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Accommodation = 4 Diopters \yZVn6GVr  
Pupil Diameter = 4 mm _/'VD!(MV  
Set aqueous humor thickness = 2.81 cy)-Rf
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Set anterior lens radius = 10.4 and conic constant = -2.375869 z&B9Yu4M7  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 {M7`"+~w  
Set lens thickness = 3.927 QqRF?%7q"q  
Set lens index of refraction = 1.42672 g{i= $xc  
Set pupil diameter = 4 fVf:voh  
DONE! 0kNKt(_  
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