[转载]FRED运用：Arizona眼睛模型 [复制链接]

简介 DPU%4te  
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。 1kiS."77x  
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模型 0X`sQNx  
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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。 9^;)~ G  
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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. vS! TnmF  
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光源 '^TQ Ubw  
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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。 }`O_  
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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。 qoNVp7uv  
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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。 ileqI/40f  
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视网膜的散射 1;; is  
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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。 =F(fum;zH  
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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。 =~)J:x\F  
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脚本 $VWeo#b  
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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： o\_@4hXf  
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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。 aoLYw 9  
余下的脚本计算与屈光度有关的所有参数。 Jj<UtD+  
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分析 EcBJ-j6d  
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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。 t0
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脚本代码 6x1!!X+)+  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. -`z`K08sT  
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Dim entity As T_ENTITY :
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Dim op As T_OPERATION =j%B`cJ66_  
Dim mat As T_MODELMATERIAL '$5.{o`s*1  
Dim A As Double TM|M#hMS  
Dim pupilDiam As Double 0JQ0lzk1  
Dim eID As Long VDCG 5QP6(  
Dim parID As Long %SV5PO@  
Dim count As Integer &<!DNXQ  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double 2OXcP
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Dim tlens As Double, nlens As Double ZI'MfkEZ*  
Dim curv As Double, conic As Double RUJkfi=$  
Dim ok As Long Dc,h(2  
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Sub Main 5r=xhOe`  
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    '用户输入对话框 G_GPnKdd  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 2$>"4 N  
        TextBox 220,21,40,21,.TextBox1 'default: 0 ]0`*gKA  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 _j$"fg  
        OKButton 40,91,90,21 g7($lt>  
        CancelButton 190,91,90,21 AlW0GK=N-p  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 W6. )7Y,  
        TextBox 220,49,40,21,.TextBox2 'default: 4 K[tQ>C@s2  
    End Dialog sFqLxSo_I  
    Dim dlg As UserDialog <qG4[W,
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    ok = Dialog (dlg) "O{_LOJ  
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    If ok=0 Then    'cancel button was pressed ?2hS<qXX  
        Print "Execution cancelled." axJuJ`+Y  
        End fj2pD Cic  
    End If {Y>5 [
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    'Assign accommodation and pupil diameter & use defaults if field left empty "N"$B~W*  
    If dlg.TextBox1 = "" Then "m*.kB)e7  
        A = 0           'Default accommodation {!? @u?M  
    Else @Q!Jzw#B  
        A = CDbl(dlg.TextBox1) XCCh*qym  
    End If K?;_T$^K  
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    If dlg.TextBox2 = "" Then g"k1O  
        pupilDiam = 4   'Default pupil diameter Vu @2  
    Else _a;E>   
        pupilDiam = CDbl(dlg.TextBox2) 5a$Q}!6E.Y  
    End If K gN=b  
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    Print " " \!!qzrq  
    Print "Accommodation = " & A & " Diopters" XJx$HM&0M  
    Print "Pupil Diameter = " & pupilDiam & " mm" .YV{wL@cB  
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    ' Calculate new parameters with accommodation !Zowe*`
 
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness m:kXr^!D  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens !+sC'/  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens G`n|fuv  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens nkI+"$Rz0  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens 2nNBX2o&_  
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    tlens = 3.767 + 0.04*A                  'Lens thickness 9Fo00"q  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction a`c#- je  
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    'Adjust parameters to account for accommodation #@ClhpLD  
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    '************************************************************************* 8Zj=:;  
    'Aqueous thickness (Position of Lens) zD#$]?@ b  
    '************************************************************************* 9+:SS1_  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) eAU0 8gM.  
    GetCustomElement eID, entity bQU{)W  
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    parID = FindFullName( "Geometry.Arizona Eye" ) `IP?w&k)  
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    ' Delete any shift(s) in z xwuGJ   
    count = 0 CbvP1*
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    While GetOperationCount(eID)>count L/ L#[  
        GetOperation eID, count, op /{)}y  
        If op.Type="ShiftZ" Then !,Ou:E?Bb  
            DeleteOperation eID,count @
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            count=count-1 Cz1Q@<)  
        End If :B^YK].  
        count=count+1 mu#IF'|b  
    Wend z3n273W>6  
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    'Set new shift in :Dt]sE_d  
    op.Type = "ShiftZ" /9SEW!E  
    op.val1 = taq |IcA8[  
    op.parent = parID lEZODc+%Y  
    AddOperation eID, op Zz,j,w0 Z  
    Print "Set aqueous humor thickness = " & taq-0.55 u%t/W0xi  
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    '************************************************************************* dd+hX$,  
    'Radius and conic constant of anterior lens lfJvN  
    '************************************************************************* aru;
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    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) -dto46X  
    GetConic eID, entity, curv, conic xK*G'3Ge  
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    SetConic eID, entity, 1/Rant, CCant e/7rr~"|  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant {6I)
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    '************************************************************************* R|@?6<  
    'Radius and conic constant of posterior lens +g9CklJ  
    '************************************************************************* \CU-a`n  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" )  JT,[;  
    GetConic eID, entity, curv, conic qjm6\ii:)  
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    SetConic eID, entity, 1/Rpost, CCpost MJ\^i4  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost gAudL)X  
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    '************************************************************************* ^g'P H{68  
    'Lens thickness (Position of posterior lens surface) YigDrW  
    '************************************************************************* QmKEl|/{u  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) 9#>t% IF~  
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    ' Delete any z-shift(s) c]/X >8;  
    count = 0 ?wi^R:2|j  
    While GetOperationCount(eID)>count 5y~Srb?2  
        GetOperation eID, count, op &cpqn2Z  
        If op.Type="ShiftZ" Then @$7'{*  
            DeleteOperation eID,count !'z"V_x~  
            count=count-1 V;LV),R?  
        End If j5:/Gl8  
        count=count+1 9Ro7xSeD  
    Wend \Dx;AKs  
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    'Set new z-shift A4tb>OM  
    op.Type = "ShiftZ" D[ v2#2  
    op.val1 = tlens Yq-Vwh/  
    op.parent = parID B9: i.rQ  
    AddOperation eID, op 0{'m":D9  
    Print "Set lens thickness = " & tlens 4T>d%Tt+)  
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    '************************************************************************* &5y|Q?  
    'Lens index of refraction D~zk2  
    '************************************************************************* +zg3/C4 S  
    eID = FindMaterial( "Lens" ) 0: N
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    GetModelMaterial eID, mat gSk0#Jt  
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    mat.Nd = nlens %BwvA_T'Q  
    SetModelMaterial eID, mat AsfmH-4)  
    Print "Set lens index of refraction = " & nlens _[pbfua  
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    '************************************************************************* B%I<6E[D  
    'Pupil diameter B'-n ^';  
    '************************************************************************* SUb:0GUa  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) S[
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    'Adjust pupil diameter (trimming volume inner hole) q\
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" X?$"dqA  
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    ' Adjust pupil location to just in front of the lens BC)1FxsGf  
    parID = FindFullName( "Geometry.Arizona Eye" ) IP!`;?T=  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) ]64pb;w"$D  
    count = 0 Xd@ d$  
    While GetOperationCount(eID)>count l@5kw]6  
        GetOperation eID, count, op ckkm}
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        If op.Type="ShiftZ" Then ,R}9n@JI^Y  
            DeleteOperation eID,count 6J<R;g23R]  
            count=count-1 gn:&akg  
        End If UE-1p  
        count=count+1 KjK-#F,@  
    Wend 3~\,VO''  
    op.Type = "ShiftZ" 5i-VnG  
    op.val1 = taq-0.01 (H;,E-
 
    op.parent = parID bl-D{)X  
    AddOperation eID, op v(]dIH  

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    Print "Set pupil diameter = " & pupilDiam Tq,dlDDOR  
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    'Update AZ Eye subassembly Description -VvN1G6.x?  
    eID = FindFullName( "Geometry.Arizona Eye" ) =C- b#4Q  
    GetEntity eID, entity fuT Bh6w&  
    entity.Description = "Accommodation = " & A & "D" m#^;V  
    SetEntity eID, entity bh+m_$X~  
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    Update [ZL<Q  
    Print "DONE!" A3.*d:A  
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End Sub c#Qlr{ES  
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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： M9.FtQhK/  
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Accommodation = 4 Diopters A}[x))r  
Pupil Diameter = 4 mm $U"pdf  
Set aqueous humor thickness = 2.81 8M,$|\U  
Set anterior lens radius = 10.4 and conic constant = -2.375869 L0qL\>#ejr  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 -Np}<O`./  
Set lens thickness = 3.927  = Atyy  
Set lens index of refraction = 1.42672 eMtQa;Lc9o  
Set pupil diameter = 4 x$z>.4  
DONE! _adW>-wQ!d  
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