[转载]FRED运用：Arizona眼睛模型 [复制链接]

简介 Ar~{=X  
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。 .CmL7 5  
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模型 7K !GK  
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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。 BD4"pcr  
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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. ,lP7 ri  
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光源 yA0Y 14\*  
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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。 |0DP} `~  
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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。 hLn&5jYHvt  
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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。 FLEg0/m0  
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视网膜的散射 @2|G|C/]O}  
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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。 q|/!0MU"  
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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。 a(g$ d2H  
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脚本 <JJkki  
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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： f5N<3m=  
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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。 I}1fEw>8  
余下的脚本计算与屈光度有关的所有参数。 {M
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分析 pO5v*oONz+  
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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。 tvK rc  
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脚本代码
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. (PyTq 5:F  
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Dim entity As T_ENTITY TIKEg10I  
Dim op As T_OPERATION ~}Kp  
Dim mat As T_MODELMATERIAL *C tsFS~  
Dim A As Double ,d3Q+9/  
Dim pupilDiam As Double hw7~i  
Dim eID As Long t.gq5Y.[  
Dim parID As Long G!-7ic_4  
Dim count As Integer w 5!ndu  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double m`[oT\  
Dim tlens As Double, nlens As Double `\nON  
Dim curv As Double, conic As Double ^7J~W'hI  
Dim ok As Long k{zs578h2  
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Sub Main #IH<HL)t%e  
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    '用户输入对话框 5~v(AB(x  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 rDK;6H:u{  
        TextBox 220,21,40,21,.TextBox1 'default: 0 A!Knp=Gw  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 H^]Nmd8Q)  
        OKButton 40,91,90,21 0EcC  
        CancelButton 190,91,90,21 .G7]&5s  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 +R3\cRM  
        TextBox 220,49,40,21,.TextBox2 'default: 4 "u .)X3  
    End Dialog ~%D^Ga7  
    Dim dlg As UserDialog 49iR8w?k  
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    ok = Dialog (dlg) :|*Gnu  
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    If ok=0 Then    'cancel button was pressed 
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        Print "Execution cancelled." C.b,]7i  
        End ^D%}V-"  
    End If wUh3Hd'  
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    'Assign accommodation and pupil diameter & use defaults if field left empty hr)+Pk  
    If dlg.TextBox1 = "" Then z }FiU
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        A = 0           'Default accommodation :w?:WH?2L  
    Else #i
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        A = CDbl(dlg.TextBox1) 6\NX
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    End If $.suu^>^w  
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    If dlg.TextBox2 = "" Then ~0'_K1(H  
        pupilDiam = 4   'Default pupil diameter b
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    Else L:|X/c9r[  
        pupilDiam = CDbl(dlg.TextBox2) h(+m<J  
    End If R=#q"9qz  
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    Print " " 0})7of  
    Print "Accommodation = " & A & " Diopters" s$SU vo1J  
    Print "Pupil Diameter = " & pupilDiam & " mm" 'xLM>6[wz  
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    ' Calculate new parameters with accommodation N'lGA;}i  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness INN/VDsJ  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens -dc"N|.  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens IS5.i95m  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens al3BWRq'f  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens (R;) 9I\  
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    tlens = 3.767 + 0.04*A                  'Lens thickness Z>>gXh<e[  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction vy2*BTU?  
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    'Adjust parameters to account for accommodation O]$*EiO\  
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    '************************************************************************* @&i#S}%/  
    'Aqueous thickness (Position of Lens) {|7OmslC@  
    '************************************************************************* a`[?,W:q  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) Kdryl  
    GetCustomElement eID, entity 1{\,5U&  
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    parID = FindFullName( "Geometry.Arizona Eye" ) c1)BGy
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    ' Delete any shift(s) in z N>cp>&j
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    count = 0 LoV*YS
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    While GetOperationCount(eID)>count _4XoUE\\  
        GetOperation eID, count, op :e0R7sj  
        If op.Type="ShiftZ" Then Yq)YS]  
            DeleteOperation eID,count &8:iB {n  
            count=count-1 ]$?zT`>(F  
        End If w>9H"Q[  
        count=count+1 P&-D0T_  
    Wend L_.xr ?  
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    'Set new shift in ~q#[5l(r8  
    op.Type = "ShiftZ" x]%4M\T``  
    op.val1 = taq [X$|dOm'N  
    op.parent = parID lo>-}xd  
    AddOperation eID, op ]'1N_m]?  
    Print "Set aqueous humor thickness = " & taq-0.55 [# tT o;q  
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    '*************************************************************************  ycAi(K  
    'Radius and conic constant of anterior lens [6/%V>EM  
    '************************************************************************* &ls
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    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) yaYIgG  
    GetConic eID, entity, curv, conic {%+3D,$)  
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    SetConic eID, entity, 1/Rant, CCant um_M}t{  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant v @I^:I  
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    '************************************************************************* LF-+5`  
    'Radius and conic constant of posterior lens 0-&sJ  
    '************************************************************************* #LNB@E  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) [ ;3EzZL  
    GetConic eID, entity, curv, conic 43orR !.Z  
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    SetConic eID, entity, 1/Rpost, CCpost Y(G*Yi?;  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost -SC2Zgi)A  
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    '************************************************************************* qS/71Kv'  
    'Lens thickness (Position of posterior lens surface) 5@%=LPV  
    '************************************************************************* )8N)Z~h  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) 7PQj7&m  
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    ' Delete any z-shift(s) sJYKt  
    count = 0 JY050FL  
    While GetOperationCount(eID)>count dn.c#,
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        GetOperation eID, count, op EK-bvZ  
        If op.Type="ShiftZ" Then t&Y^W <  
            DeleteOperation eID,count omUl2C  
            count=count-1 DRBYH(  
        End If FDG
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        count=count+1 pQgOT0f  
    Wend J\,e/{,X  
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    'Set new z-shift ,9l!fT?iH  
    op.Type = "ShiftZ" :+Je989\[C  
    op.val1 = tlens )>A%F
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    op.parent = parID px(1Ppb9  
    AddOperation eID, op @1qUC"Mg  
    Print "Set lens thickness = " & tlens $gD(MKR)~  
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    '************************************************************************* k^%TJ.y@  
    'Lens index of refraction $lG--s  
    '************************************************************************* &MGgO
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    eID = FindMaterial( "Lens" ) jQwg)E+o;  
    GetModelMaterial eID, mat DkMC!Q\  
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    mat.Nd = nlens 2Z1(J% 7  
    SetModelMaterial eID, mat \?mU$,voI  
    Print "Set lens index of refraction = " & nlens ()IgSj?,  
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    '************************************************************************* XuAc3~HAd  
    'Pupil diameter W,oV$ s^  
    '************************************************************************* T6?d`i i1  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) ah@GSu;7  
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    'Adjust pupil diameter (trimming volume inner hole) apWrcaj  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" nOoh2jUM  
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    ' Adjust pupil location to just in front of the lens 1ZH8/1gWI  
    parID = FindFullName( "Geometry.Arizona Eye" ) oO9iB:w  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) ++RmaZ  
    count = 0 $/(/v?3][e  
    While GetOperationCount(eID)>count _f2iz4  
        GetOperation eID, count, op o>k-~v7  
        If op.Type="ShiftZ" Then @P*P8v8:  
            DeleteOperation eID,count A
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            count=count-1 ' xq5tRg>  
        End If M(f*hOG{Y  
        count=count+1 ;0}"2aGY  
    Wend .;sPG  
    op.Type = "ShiftZ" Tf]VcEF  
    op.val1 = taq-0.01 -8J@r2\
 
    op.parent = parID gGz_t,=  
    AddOperation eID, op RPqn#B  
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    Print "Set pupil diameter = " & pupilDiam +( 7vmC.  
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    'Update AZ Eye subassembly Description "Q!{8 9Y  
    eID = FindFullName( "Geometry.Arizona Eye" ) T//+&Sk[  
    GetEntity eID, entity "+"dALX{3K  
    entity.Description = "Accommodation = " & A & "D" ^\t">NJ^  
    SetEntity eID, entity WQ
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    Update ~bQ:gArk  
    Print "DONE!" AyXKhj#Ml  
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End Sub 6E%k{ r  
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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： jtCob'n8  
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Accommodation = 4 Diopters Z19y5?uR  
Pupil Diameter = 4 mm fH{$LjH(  
Set aqueous humor thickness = 2.81 B ~bU7.Cd  
Set anterior lens radius = 10.4 and conic constant = -2.375869 Ppn
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Set posterior lens radius = -4.424557 and conic constant = -3.081019 ag4^y&  
Set lens thickness = 3.927 G`K7P`m  
Set lens index of refraction = 1.42672 ,=yIfbFQ  
Set pupil diameter = 4 J\},o|WI  
DONE! b8Ad*f\  
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