[分享]Arizona眼睛模型 [复制链接]

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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。 !F{5"$  
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模型 d>F=|dakL  
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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。 vO" $Xw  
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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. >VqMSe_v  
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光源 gDnG!i+  
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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。 aisX56Lc  
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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。 S5RS?ya  
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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。 ,K7C2PV6  
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视网膜的散射 I_xJ[ALdm  
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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。 M 0->  
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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。 Uy ;oJY  
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脚本 !0`ZK-nA6  
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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： 0y'34}  
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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。 . 36'=K  
余下的脚本计算与屈光度有关的所有参数。 iG!MIt*  
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分析 )X\3bPDJR  
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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。 >E"FoZM=  
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脚本代码 u[2R>=  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. RW
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Dim entity As T_ENTITY #D//oL"u]  
Dim op As T_OPERATION s'\"%~nF<  
Dim mat As T_MODELMATERIAL 94nvh:n  
Dim A As Double cx_"{`+e  
Dim pupilDiam As Double *N'B(j/  
Dim eID As Long
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Dim parID As Long shn`>=0.&  
Dim count As Integer .M:,pw"S]  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double W,Dr2$V  
Dim tlens As Double, nlens As Double aKCCFHq t!  
Dim curv As Double, conic As Double w #(XiH*  
Dim ok As Long E pM 4+  
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Sub Main JpS:}yyJ>N  
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    '用户输入对话框 9zO;sg;3  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 z8z U3?  
        TextBox 220,21,40,21,.TextBox1 'default: 0  ]g?G0m  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 oF,8j1  
        OKButton 40,91,90,21 ={maCYlE.  
        CancelButton 190,91,90,21 !2&h=;i~V  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 ?wwY8e?S  
        TextBox 220,49,40,21,.TextBox2 'default: 4 ?Cu#(  
    End Dialog sMO3eNLn  
    Dim dlg As UserDialog PVEEKKJP]J  
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    ok = Dialog (dlg) \mc~w4B[)3  
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    If ok=0 Then    'cancel button was pressed $$qhX]^~  
        Print "Execution cancelled." hr6f
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        End M5)6|T  
    End If Nt/*VYUn  
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    'Assign accommodation and pupil diameter & use defaults if field left empty :syR4A WM  
    If dlg.TextBox1 = "" Then >{GC@Cw  
        A = 0           'Default accommodation u4+VG5.rhT  
    Else W=)}=^N0  
        A = CDbl(dlg.TextBox1) =}c~BHT  
    End If TvdmgVNP  
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    If dlg.TextBox2 = "" Then pbm4C0W}  
        pupilDiam = 4   'Default pupil diameter 'w9tZO\2  
    Else kV<VhBql!  
        pupilDiam = CDbl(dlg.TextBox2) };zF&  
    End If PwDQ<   
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    Print " " b|fq63ar;  
    Print "Accommodation = " & A & " Diopters" g]d
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    Print "Pupil Diameter = " & pupilDiam & " mm" FP9ZOoog  
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    ' Calculate new parameters with accommodation 'Y"q=@Ei9  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness `C!Pe84(  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens Z.R^@@RqJ  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens "sHD8TUX  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens $\P!
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    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens rq
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    tlens = 3.767 + 0.04*A                  'Lens thickness  R6AZIN:  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction fYCAwS{  
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    'Adjust parameters to account for accommodation fwl RwH(  
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    '************************************************************************* _N<qrH^;  
    'Aqueous thickness (Position of Lens) 7`WK1_rR\  
    '************************************************************************* cc^V~-ph  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) zR`]8E]  
    GetCustomElement eID, entity .eeM&n;c  
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    parID = FindFullName( "Geometry.Arizona Eye" ) +*|E%pq  
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    ' Delete any shift(s) in z 2&Efqy8}DZ  
    count = 0 a!>AhOk.  
    While GetOperationCount(eID)>count 2oq>tnYyV[  
        GetOperation eID, count, op I.( 9{  
        If op.Type="ShiftZ" Then }S42.f.p  
            DeleteOperation eID,count Ajq<=y`NzV  
            count=count-1 e1'_]   
        End If h"<r
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        count=count+1 _|s{G  
    Wend i
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    'Set new shift in Z~P5SEg  
    op.Type = "ShiftZ" ~w!<J-z)  
    op.val1 = taq 2 K` hH  
    op.parent = parID
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    AddOperation eID, op 
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    Print "Set aqueous humor thickness = " & taq-0.55 g/T`4"p[H  
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    '************************************************************************* @s@r5uR9B  
    'Radius and conic constant of anterior lens pRYt.}/K  
    '************************************************************************* W;hI[9  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) 6t@3 a?  
    GetConic eID, entity, curv, conic ?N`W,  
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    SetConic eID, entity, 1/Rant, CCant 8# 9.a]AX  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant Lo !kv*  
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    '************************************************************************* h],_1!0  
    'Radius and conic constant of posterior lens aA\v  
    '************************************************************************* O*c+TiTb  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) >pn?~  
    GetConic eID, entity, curv, conic :]?I|.a  
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    SetConic eID, entity, 1/Rpost, CCpost eP;lH~!.0  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost 7<X_
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    '************************************************************************* 
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    'Lens thickness (Position of posterior lens surface) Plt~l3_  
    '************************************************************************* sdrE4-zd  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) ]V}";cm;2  
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    ' Delete any z-shift(s) ?HU(0Vgn'  
    count = 0 M`S >Q2{  
    While GetOperationCount(eID)>count V>z8*28S.  
        GetOperation eID, count, op q?JP\_o:  
        If op.Type="ShiftZ" Then *n}{)Ef  
            DeleteOperation eID,count tX6n~NJ$  
            count=count-1 7eZ,; x  
        End If WG1x:,-  
        count=count+1 %}2 s74D*Z  
    Wend w 8T#~Dc  
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    'Set new z-shift z${DW@o3  
    op.Type = "ShiftZ" [?_^Cy  
    op.val1 = tlens 5Vf#
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    op.parent = parID 7!z0)Ai_>=  
    AddOperation eID, op td{$c6  
    Print "Set lens thickness = " & tlens v-g2k_o|  
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    '************************************************************************* i.6c;KU  
    'Lens index of refraction 8)'OXR0/  
    '************************************************************************* X8y&|uH  
    eID = FindMaterial( "Lens" ) 1@;Dn'  
    GetModelMaterial eID, mat Qp]V~s(  
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    mat.Nd = nlens 7'CdDB6&.  
    SetModelMaterial eID, mat AvH^9zEE(  
    Print "Set lens index of refraction = " & nlens =5',obYN>c  
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    '************************************************************************* PkMN@JS  
    'Pupil diameter oyK'h9Wt1  
    '************************************************************************* [Vc8j&:L  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) Qne@Vf kA  
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    'Adjust pupil diameter (trimming volume inner hole) q\/ph(HF  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" &M&*3  
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    ' Adjust pupil location to just in front of the lens 3c}@_Yn  
    parID = FindFullName( "Geometry.Arizona Eye" ) }&F|u0@b  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) fX2sjfk  
    count = 0 C[6} 8J|  
    While GetOperationCount(eID)>count n#|ljC  
        GetOperation eID, count, op wQEsq<  
        If op.Type="ShiftZ" Then kc-=5l  
            DeleteOperation eID,count #p*D.We  
            count=count-1 -U.>K,M  
        End If Qzt'ZK  
        count=count+1 )[+82~F  
    Wend L 4V,y>  
    op.Type = "ShiftZ" ?(0=+o(`  
    op.val1 = taq-0.01 S6Y2(qdP  
    op.parent = parID Gh>&+UA'$1  
    AddOperation eID, op ~G,_4}#"pM  
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    Print "Set pupil diameter = " & pupilDiam g[';1}/B4  
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    'Update AZ Eye subassembly Description 4A"3C  
    eID = FindFullName( "Geometry.Arizona Eye" ) #9zpJ
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    GetEntity eID, entity Bs)'Gk`1  
    entity.Description = "Accommodation = " & A & "D" <-;/,uu  
    SetEntity eID, entity `i`+yh>pc#  
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    Update i'V("  
    Print "DONE!" ,4:=n$e 0  
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End Sub y^Uh<L0M  
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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： ,_iq$I;  
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Accommodation = 4 Diopters mC2K &'[  
Pupil Diameter = 4 mm }D>#AFs6#  
Set aqueous humor thickness = 2.81 qYoB;gp  
Set anterior lens radius = 10.4 and conic constant = -2.375869 l^F ?^kP  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 s@Dln Du.  
Set lens thickness = 3.927 ;3x*pjLG:Q  
Set lens index of refraction = 1.42672 aD]! eP/)  
Set pupil diameter = 4 @`
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DONE! t:MSV?  
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