[转载]FRED运用：Arizona眼睛模型 [复制链接]

简介 8C1 'g7A<  
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。 Fp52|w_  
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模型 [EUp4%Z #  
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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。 z DDvXz  
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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. R4+Gmx1  
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光源 PMER~}^  
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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。 egcJ@Of  
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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。 6(1xU\x  
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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。 LgN\%5f-  
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视网膜的散射 oNV5su  
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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。 ?U~}uG^  
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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。 dxm_AUM  
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脚本 c-S_{~~  
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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： 0fc]RkHs"  
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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。 =X6+}YQ"  
余下的脚本计算与屈光度有关的所有参数。 hR;J#w  
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分析 7/c[ f  
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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。 )u{)"m`&[J  
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脚本代码 gemjLuf  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. qK ,mG{  
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Dim entity As T_ENTITY #L\t)W  
Dim op As T_OPERATION IT \Pj_  
Dim mat As T_MODELMATERIAL 6`LC(Nv%-n  
Dim A As Double H*U\P2C!)  
Dim pupilDiam As Double W!a~ #R/r-  
Dim eID As Long *|c*/7]<  
Dim parID As Long #A|~s;s>N  
Dim count As Integer ~<0!sE&y  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double 7h?yAgDv~  
Dim tlens As Double, nlens As Double -"L)<J@gQ?  
Dim curv As Double, conic As Double %I]?xe6  
Dim ok As Long f3h&K}x  
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Sub Main hv xvwV1  
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    '用户输入对话框 \!8`kC  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 y%T5"p$,  
        TextBox 220,21,40,21,.TextBox1 'default: 0 :j/PtNT@  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 J90q\_dY.  
        OKButton 40,91,90,21 ],r?]>  
        CancelButton 190,91,90,21 b@J&jE~d  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 *b"(r|Ko  
        TextBox 220,49,40,21,.TextBox2 'default: 4 )Qve[O  
    End Dialog UXB[3SP  
    Dim dlg As UserDialog qlUYu"`i  
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    ok = Dialog (dlg) [c?']<f4  
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    If ok=0 Then    'cancel button was pressed Xq&x<td  
        Print "Execution cancelled." YBg
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        End 4+mawyM  
    End If nbYkr*: "t  
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    'Assign accommodation and pupil diameter & use defaults if field left empty ~Z5?\a2Ld  
    If dlg.TextBox1 = "" Then ;??wLNdf-  
        A = 0           'Default accommodation uh`@qmu)  
    Else hoASrj{s  
        A = CDbl(dlg.TextBox1) n5_r 3{  
    End If J
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    If dlg.TextBox2 = "" Then v>Il#  
        pupilDiam = 4   'Default pupil diameter >Uvtsj#  
    Else [~)i<V|qJ  
        pupilDiam = CDbl(dlg.TextBox2) 3nBbPP_  
    End If iUh_rX9A"  
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    Print " " z)5n&w S  
    Print "Accommodation = " & A & " Diopters" {Ny\9r  
    Print "Pupil Diameter = " & pupilDiam & " mm" 1W;3pN  
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    ' Calculate new parameters with accommodation uVqJl{e\  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness xiU-}H'o  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens  1$idF  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens UQ>GAzh  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens -mZo`  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens 8 Oeg"d  
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    tlens = 3.767 + 0.04*A                  'Lens thickness h`%K\C  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction &RXd1>|c2  
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    'Adjust parameters to account for accommodation 6K P!o  
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    '************************************************************************* U6X
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    'Aqueous thickness (Position of Lens) nx=#QLi  
    '************************************************************************* l{#m"S7J^  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) w;QDQ fx0  
    GetCustomElement eID, entity h. i&[RnX  
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    parID = FindFullName( "Geometry.Arizona Eye" ) 3HbHl?-UNU  
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    ' Delete any shift(s) in z ~1Tz[\H#R  
    count = 0 p"H8;fPA0  
    While GetOperationCount(eID)>count 2xe_Q70II  
        GetOperation eID, count, op Beqhe\{  
        If op.Type="ShiftZ" Then d5A!kU _.  
            DeleteOperation eID,count zx-+u7qKH  
            count=count-1 .EloBP  
        End If
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        count=count+1 SX^fh
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    Wend 5F2+o#*h  
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    'Set new shift in ejo4mQ]a  
    op.Type = "ShiftZ" *"fg@B5  
    op.val1 = taq .F#mT h  
    op.parent = parID d?N"NqaN  
    AddOperation eID, op Pms3X  
    Print "Set aqueous humor thickness = " & taq-0.55 _$ixE~w-!  
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    '************************************************************************* ? |8&!F  
    'Radius and conic constant of anterior lens bw
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    '************************************************************************* GJO/']k  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) 6j"(/X|Ex5  
    GetConic eID, entity, curv, conic ?qO,=ms>-  
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    SetConic eID, entity, 1/Rant, CCant =_":Z!_  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant }#'KM
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    '************************************************************************* sTG+c E  
    'Radius and conic constant of posterior lens 8~HC0o\2  
    '************************************************************************* ,xD{A}}V  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) FG#j0#|*  
    GetConic eID, entity, curv, conic eaX`S.!jR  
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    SetConic eID, entity, 1/Rpost, CCpost (la<X<w  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost tMAa$XrZj  
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    '************************************************************************* Z}NAH`V`:+  
    'Lens thickness (Position of posterior lens surface) W77JXD93  
    '************************************************************************* H&03>.b  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) r`;C9#jZ  
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    ' Delete any z-shift(s) :/~vaCZ  
    count = 0 `n5c|`6  
    While GetOperationCount(eID)>count 5)nv  
        GetOperation eID, count, op NWAF4i
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        If op.Type="ShiftZ" Then DGd&x^C  
            DeleteOperation eID,count (Wx)YI  
            count=count-1 h5f>'l
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        End If @\"*Z&]8z0  
        count=count+1 tjd"05"@:  
    Wend q#p)E=$  
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    'Set new z-shift $AXz/fGV  
    op.Type = "ShiftZ" .\d0lJSr  
    op.val1 = tlens '
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    op.parent = parID ]~K&mNo  
    AddOperation eID, op rmabm\QY  
    Print "Set lens thickness = " & tlens lwY{rWo  
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    '************************************************************************* dt \O7Rjw8  
    'Lens index of refraction vlPE8U=  
    '************************************************************************* }oN(nPxv9  
    eID = FindMaterial( "Lens" ) J.nVEqLZ  
    GetModelMaterial eID, mat gMGg9U$@  
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    mat.Nd = nlens N)!v-z,k  
    SetModelMaterial eID, mat <>e<Xd:77{  
    Print "Set lens index of refraction = " & nlens z5vryhX_Z  
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    '************************************************************************* 7S1!|*/ I  
    'Pupil diameter ^=W&p%Y(!  
    '************************************************************************* CYn}wkz  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) PR'FSTg  
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    'Adjust pupil diameter (trimming volume inner hole) FRg6-G/S  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" uLCU3nI  
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    ' Adjust pupil location to just in front of the lens )/ZSb1!  
    parID = FindFullName( "Geometry.Arizona Eye" ) +>3c+h,%.  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) X<QE]RZ  
    count = 0 q#a21~S<  
    While GetOperationCount(eID)>count 1(?J>{-lw  
        GetOperation eID, count, op *Qf}4a0  
        If op.Type="ShiftZ" Then Y
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            DeleteOperation eID,count t<k8.9 M$  
            count=count-1 Tk!b`9
 
        End If ~ZNhU;%YW  
        count=count+1 5`uS<[vA  
    Wend :3t])mL#   
    op.Type = "ShiftZ" AFFLnLA<L  
    op.val1 = taq-0.01 E+)Go-rS(  
    op.parent = parID y2U:( H:l!  
    AddOperation eID, op -Fdi,\e  
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    Print "Set pupil diameter = " & pupilDiam :L[6a>"neE  
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    'Update AZ Eye subassembly Description @j (jOe  
    eID = FindFullName( "Geometry.Arizona Eye" ) /t
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    GetEntity eID, entity
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    entity.Description = "Accommodation = " & A & "D"  %aKkk)s  
    SetEntity eID, entity ^pjez+  
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    Update
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    Print "DONE!" nKO&ffb'<  
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End Sub X]fw9tZ  
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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： k:TfE6JZ  
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Accommodation = 4 Diopters BQU5[8l  
Pupil Diameter = 4 mm *Vl =PNn-  
Set aqueous humor thickness = 2.81 t0>{0 5  
Set anterior lens radius = 10.4 and conic constant = -2.375869 8joQPHkI\  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 c6HU'%v  
Set lens thickness = 3.927 ptR  
Set lens index of refraction = 1.42672 fh_ .J[Y.k  
Set pupil diameter = 4 3ngLE
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DONE! hNle;&*F  
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