[技术]Arizona眼睛模型 [复制链接]

简介
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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。 HX:rVHY  
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模型 #97w6,P+  
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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。 :3Hr:~  
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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. 6?v)Hb}J%d  
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光源 W{2(fb  
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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。 Z6I^HG{:  
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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。 REvY`   
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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。 H%:~&_D  
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视网膜的散射 ovn)lIs  
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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。 h)qapC5z,  
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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。 HJ2r~KIw  
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脚本 df
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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： pZ,P_
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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。 `4'['x  
余下的脚本计算与屈光度有关的所有参数。 i#M$i*H*A  
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分析 csV.AN'obq  
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屈光度为4，光瞳直径为4mm，字母F点在视网膜上所成的像。 B|-E3v:f4  
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脚本代码 j`Xe0U<  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. Wv]NFHe#  
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Dim entity As T_ENTITY _[8BAm  
Dim op As T_OPERATION , wT$L3  
Dim mat As T_MODELMATERIAL +IiL(\ew  
Dim A As Double OYEL`!Q  
Dim pupilDiam As Double *OT6)]|k  
Dim eID As Long 1YmB2h[Z  
Dim parID As Long {BBL`tg60  
Dim count As Integer vt3yCS  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double 1)8;9 Ba:  
Dim tlens As Double, nlens As Double Htseu`>_$  
Dim curv As Double, conic As Double ,nJYYM   
Dim ok As Long g_\U-pzr  
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Sub Main ON{
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    '用户输入对话框 jOppru5U  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 "Ldi<xq%xl  
        TextBox 220,21,40,21,.TextBox1 'default: 0 t'bzhPQO)f  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 GVT+c@Gx  
        OKButton 40,91,90,21 ]~:9b[G2  
        CancelButton 190,91,90,21 f>Mg.9gJ(  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 DS,"^K  
        TextBox 220,49,40,21,.TextBox2 'default: 4 $2=-Q/lM  
    End Dialog )vB,eZq  
    Dim dlg As UserDialog 8}FZ1h2 4  
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    ok = Dialog (dlg) m"P"iK/Av(  
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    If ok=0 Then    'cancel button was pressed >qjQ;z[  
        Print "Execution cancelled." Tti]H9g_  
        End IG?044Y  
    End If Re3vW re  
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    'Assign accommodation and pupil diameter & use defaults if field left empty LEoL6ga  
    If dlg.TextBox1 = "" Then __\Tv>Y  
        A = 0           'Default accommodation LHjGlBy  
    Else 6mr5`5~w  
        A = CDbl(dlg.TextBox1) )x1LOMe  
    End If /xmUu0H$R  
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    If dlg.TextBox2 = "" Then XOQj?Q7)U  
        pupilDiam = 4   'Default pupil diameter &BnK[Q8X  
    Else lLy^@s  
        pupilDiam = CDbl(dlg.TextBox2) c!Gnd*!?-  
    End If u?[dy n  
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    Print " " 2)DrZI  
    Print "Accommodation = " & A & " Diopters" ">QNiR!  
    Print "Pupil Diameter = " & pupilDiam & " mm" JTw\5j  
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    ' Calculate new parameters with accommodation Ti`H?9t  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness './j<2|;U  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens )v&r^DR_  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens ob=GB71j55  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens ,&S:(b[D  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens : E`N0UA  
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    tlens = 3.767 + 0.04*A                  'Lens thickness l?:!G7ie  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction (J(JB}[X,  
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    'Adjust parameters to account for accommodation >'3J. FY  
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    '************************************************************************* LyM"  
    'Aqueous thickness (Position of Lens) qP<wf=wY  
    '************************************************************************* HMbF#!E  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) FCv3ZF?K  
    GetCustomElement eID, entity Y_n^6 ;  
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    parID = FindFullName( "Geometry.Arizona Eye" ) 0\f3La  
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    ' Delete any shift(s) in z V3&_ST  
    count = 0 ;C=C`$Q  
    While GetOperationCount(eID)>count hO3>Gl5<  
        GetOperation eID, count, op 1*aw~nY
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        If op.Type="ShiftZ" Then @l~zn%!X  
            DeleteOperation eID,count *C*n(the  
            count=count-1 )8Defuxk  
        End If MY11 5%  
        count=count+1 '&{`^l/MH  
    Wend
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    'Set new shift in J8[N!qDCj  
    op.Type = "ShiftZ" ~Aul 7[IH  
    op.val1 = taq /*DC`,q  
    op.parent = parID Tl9KL%9  
    AddOperation eID, op q1QrtJFPG  
    Print "Set aqueous humor thickness = " & taq-0.55 z>$AZ>t%J$  
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    '************************************************************************* A7!!kR":  
    'Radius and conic constant of anterior lens A;E7~qOG  
    '************************************************************************* _h1n]@ d5  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) N<V,5  
    GetConic eID, entity, curv, conic Yhu 6QyRV  
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    SetConic eID, entity, 1/Rant, CCant "I.PV$Rxl  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant 5(kRFb'31F  
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    '************************************************************************* |U}al[  
    'Radius and conic constant of posterior lens / 0Z_$Q&e  
    '************************************************************************* A%S6&!I:(  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) 4OL
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    GetConic eID, entity, curv, conic qE73M5L&  
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    SetConic eID, entity, 1/Rpost, CCpost ][R
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    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost 3
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    '************************************************************************* alM ^ X  
    'Lens thickness (Position of posterior lens surface) $agd9z,&m  
    '************************************************************************* -s Iji)t  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) 8':^tMd  
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    ' Delete any z-shift(s) u'"VbW3u n  
    count = 0 595P04  
    While GetOperationCount(eID)>count |1vikG8  
        GetOperation eID, count, op )sg@HFhY'  
        If op.Type="ShiftZ" Then Qx,jUL#2  
            DeleteOperation eID,count Zr`pOUk!4  
            count=count-1 {L 7O{:J  
        End If :BFecS&i5  
        count=count+1 lc%2fVG-e  
    Wend i^LLKx7M&  
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    'Set new z-shift }r`m(z$z  
    op.Type = "ShiftZ" (9bFIvMc  
    op.val1 = tlens 5[\m
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    op.parent = parID rap`[O|l=  
    AddOperation eID, op zX+NhTTB  
    Print "Set lens thickness = " & tlens
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    '************************************************************************* OmO/x  
    'Lens index of refraction *^]Hqf(`  
    '************************************************************************* bnS"@^M  
    eID = FindMaterial( "Lens" ) E;7vGGf]  
    GetModelMaterial eID, mat D;%(Z!  
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    mat.Nd = nlens XI#1)  
    SetModelMaterial eID, mat O=c^Ak   
    Print "Set lens index of refraction = " & nlens 7;H!F!K]  
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    '************************************************************************* 
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    'Pupil diameter ~4HS 2\  
    '************************************************************************* u;$g13  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) WVPnyVDc  
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    'Adjust pupil diameter (trimming volume inner hole) L[4Su;D  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" ZuV/!9qU  
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    ' Adjust pupil location to just in front of the lens 5.st!Lp1  
    parID = FindFullName( "Geometry.Arizona Eye" ) i@7b  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) rSGp]W|  
    count = 0 o/uA_19  
    While GetOperationCount(eID)>count <[9{Lg*D  
        GetOperation eID, count, op \-A=??@H  
        If op.Type="ShiftZ" Then k)+2+hX&>  
            DeleteOperation eID,count ZMs$C3  
            count=count-1 ,dhSc<:LT  
        End If R7xKVS_MP  
        count=count+1 iC]=S}  
    Wend {<f_,Nlc  
    op.Type = "ShiftZ" e))fbv&V  
    op.val1 = taq-0.01 Qs24b   
    op.parent = parID Q2wEt >0a  
    AddOperation eID, op DQ'yFPE  
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    Print "Set pupil diameter = " & pupilDiam cB~D3a0Th  
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    'Update AZ Eye subassembly Description ;9w:%c1  
    eID = FindFullName( "Geometry.Arizona Eye" ) ".Lwq_  
    GetEntity eID, entity ~&bn} M>W  
    entity.Description = "Accommodation = " & A & "D" ` drds  
    SetEntity eID, entity e
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    Update fJ \bm  
    Print "DONE!" +:@lde]/p  
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End Sub =7&2-'(@  
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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： fB~BVYi  
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Accommodation = 4 Diopters r`? bYoz  
Pupil Diameter = 4 mm ^Fmp"[q  
Set aqueous humor thickness = 2.81 d@o1<Q  
Set anterior lens radius = 10.4 and conic constant = -2.375869 v
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Set posterior lens radius = -4.424557 and conic constant = -3.081019 zoFCHsr  
Set lens thickness = 3.927 E1p?v!  
Set lens index of refraction = 1.42672 +&t`"lRl&  
Set pupil diameter = 4 UPs7{We W  
DONE! U-uBz4Gha