[分享]Arizona眼睛模型 [复制链接]

简介 hpAIIgn  
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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。 '# (lq5 c  
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模型 ^z)lEO  
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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。 !$_mWz  
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在FRED中使用0屈光度来创建的，光瞳加在了透镜的前面。材料是创建一个新的材料并选择类型“Model Material”,输入的参数是nd和vd. [ >vS+G  
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光源 ;q$<]X_S)}  
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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。 :ye)%UU"|:  
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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。 Dq-h`lh!D#  
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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。 zIdQ^vm8Q  
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视网膜的散射 TFM}
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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。 FWD9!M
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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。 # ^%'*/z  
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脚本 Sfvi|kZX  
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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： 'z!I#Y!Y  
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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。 H
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余下的脚本计算与屈光度有关的所有参数。 b
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分析 moc_}(  
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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。 O %)+ w  
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脚本代码 <:%Iq13D  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. \kg2pF[V  
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Dim entity As T_ENTITY 1"!<e$&$X  
Dim op As T_OPERATION Q2tGe~H  
Dim mat As T_MODELMATERIAL WOg_Pn9HI  
Dim A As Double AS8T!  
Dim pupilDiam As Double Mr`u!T&sc  
Dim eID As Long #}B~V3UD  
Dim parID As Long {&2$1p/9'  
Dim count As Integer Ii4Byyfx  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double ;APg!5X  
Dim tlens As Double, nlens As Double {yfG_J  
Dim curv As Double, conic As Double }7&;YAt  
Dim ok As Long ^ S%4R'  
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Sub Main bu$5gGWVf  
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    '用户输入对话框 v3hNvcMpf  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 - +>
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        TextBox 220,21,40,21,.TextBox1 'default: 0 Bp4QHv9xqL  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 `N|WCiBV.  
        OKButton 40,91,90,21 xXHz)w  
        CancelButton 190,91,90,21 al"1T-  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1
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        TextBox 220,49,40,21,.TextBox2 'default: 4 q Rt
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    End Dialog WQ6E8t)  
    Dim dlg As UserDialog 6?hv,^  
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    ok = Dialog (dlg) m&; t;&#  
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    If ok=0 Then    'cancel button was pressed ~v<r\8`OI2  
        Print "Execution cancelled." 6o{anHBB  
        End ,@[Q:fY  
    End If gp$+Qd  
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    'Assign accommodation and pupil diameter & use defaults if field left empty q4U?}=PD  
    If dlg.TextBox1 = "" Then o^>*aQ!7<D  
        A = 0           'Default accommodation N\xqy-L9  
    Else VJ1si0vWtq  
        A = CDbl(dlg.TextBox1) Oys.8%+ P  
    End If YF."D%?  
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    If dlg.TextBox2 = "" Then we{*%8I;  
        pupilDiam = 4   'Default pupil diameter _c%~\LOk  
    Else SXgpj  
        pupilDiam = CDbl(dlg.TextBox2) fHwh6|  
    End If ]YwIuz6]  
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    Print " " EJL45R>  
    Print "Accommodation = " & A & " Diopters" mu:Q2t^  
    Print "Pupil Diameter = " & pupilDiam & " mm" ( XE`,#  
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    ' Calculate new parameters with accommodation *rW]HNz  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness -h.']^I  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens ~6@~fhu  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens F\>`j  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens 8zZR%fZ  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens Hm4lR{A  
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    tlens = 3.767 + 0.04*A                  'Lens thickness EB>laZy>  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction /T_tI R>  
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    'Adjust parameters to account for accommodation %f, 9  
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    '************************************************************************* t6js@Ih  
    'Aqueous thickness (Position of Lens) \r<&7x#j  
    '************************************************************************* "
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    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) !Ng^k>*h  
    GetCustomElement eID, entity s{A-K5S  
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    parID = FindFullName( "Geometry.Arizona Eye" ) o#w6]Fmc  
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    ' Delete any shift(s) in z UVU}  
    count = 0 @*_#zU#g  
    While GetOperationCount(eID)>count C'mmo&Pd  
        GetOperation eID, count, op v*#Z{)r  
        If op.Type="ShiftZ" Then 12cfqIo9  
            DeleteOperation eID,count `&
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            count=count-1 )[zyvU. J3  
        End If <2,@rYe/  
        count=count+1 ]4hXK!^Uu  
    Wend iiRK3m  
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    'Set new shift in )vPce  
    op.Type = "ShiftZ" AV%Q5Mi}  
    op.val1 = taq [IW@mn>  
    op.parent = parID z.[L1AGa|s  
    AddOperation eID, op E
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    Print "Set aqueous humor thickness = " & taq-0.55 =XoNk1  
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    '************************************************************************* q9Fc0(&Vf  
    'Radius and conic constant of anterior lens 7N'F]x  
    '************************************************************************* V <k_Q@K  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) ]kc_wFT<  
    GetConic eID, entity, curv, conic %zX'u.}8#  
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    SetConic eID, entity, 1/Rant, CCant EiT raWV"O  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant 2|Tt3/Rn  
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    '************************************************************************* oNiS"\t  
    'Radius and conic constant of posterior lens o AQ92~b  
    '************************************************************************* %/'[GC'y!  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) Ke,-8e#Q  
    GetConic eID, entity, curv, conic "~FXmKcX  
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    SetConic eID, entity, 1/Rpost, CCpost w7%N=hL1
 
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost .+B!mmp  
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    '*************************************************************************
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    'Lens thickness (Position of posterior lens surface) 5B98}N  
    '************************************************************************* rj{'X  /  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) _I'O4s1S  
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    ' Delete any z-shift(s) OU{PVF={   
    count = 0 %%-kUe  
    While GetOperationCount(eID)>count SX FF  
        GetOperation eID, count, op EA8(_}  
        If op.Type="ShiftZ" Then =`/X Wem  
            DeleteOperation eID,count I5 2wTl0  
            count=count-1 )6AOP-M.9  
        End If o-x_[I|@  
        count=count+1 X;}_[=-  
    Wend S>H W`   
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    'Set new z-shift }hBv?B2/1  
    op.Type = "ShiftZ" zV2c`he%z  
    op.val1 = tlens 4CN8>J'-  
    op.parent = parID v}cm-_*v  
    AddOperation eID, op iP_rEi*-J  
    Print "Set lens thickness = " & tlens B:^U~sR  
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    '************************************************************************* c9ghR0WM  
    'Lens index of refraction `Cb$
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    '************************************************************************* JG4&eK$-  
    eID = FindMaterial( "Lens" ) f0hi70\(X  
    GetModelMaterial eID, mat !p9B
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    mat.Nd = nlens 4Uwt--KtFh  
    SetModelMaterial eID, mat AV8TP-Ls+  
    Print "Set lens index of refraction = " & nlens xt`znNN  
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    '************************************************************************* c=| a\\  
    'Pupil diameter TZHqn6  
    '************************************************************************* 0,/[r/=jT  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) ' u0{h  
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    'Adjust pupil diameter (trimming volume inner hole) Dxu)by  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" QeQbO  
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    ' Adjust pupil location to just in front of the lens N;D+]_;0|  
    parID = FindFullName( "Geometry.Arizona Eye" ) ]_-$  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) A"P1B]  
    count = 0 OPjscc5  
    While GetOperationCount(eID)>count p]aIMF_  
        GetOperation eID, count, op ''WX  
        If op.Type="ShiftZ" Then q$HBPR4h  
            DeleteOperation eID,count kW(8i}bg  
            count=count-1 hA~}6Qn  
        End If DSnsi@Mi  
        count=count+1 JHMj4Zkp  
    Wend G-:DMjvN  
    op.Type = "ShiftZ" OZv&{_b_  
    op.val1 = taq-0.01 uZ'5&k96T  
    op.parent = parID k5PzY!N  
    AddOperation eID, op hpw;w}m  
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    Print "Set pupil diameter = " & pupilDiam }- +;{u  
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    'Update AZ Eye subassembly Description y\%4Dir  
    eID = FindFullName( "Geometry.Arizona Eye" ) 5N[Y
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    GetEntity eID, entity 1-b,X]i  
    entity.Description = "Accommodation = " & A & "D" FEP\5d>  
    SetEntity eID, entity a<HM|dcst  
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    Update 3yZ@i<rfH  
    Print "DONE!" \KPz  
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End Sub .II'W3Fr  
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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： E*'O))  
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Accommodation = 4 Diopters &0o&!P8CB  
Pupil Diameter = 4 mm vR`KRI`{  
Set aqueous humor thickness = 2.81 ,Wdyg8&.  
Set anterior lens radius = 10.4 and conic constant = -2.375869 T*H4kM  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 f< '~K  
Set lens thickness = 3.927 iI_Fbw8  
Set lens index of refraction = 1.42672 2Nj0 Hqjq  
Set pupil diameter = 4 t qER;L  
DONE! */qv}  
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