[技术]Arizona眼睛模型 [复制链接]

简介 =$%-RX7  
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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。 9g# 6
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模型 &kn?=NW  
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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。 !1K.HdK  
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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. ROvY,-?  
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光源 9I`0`o"A  
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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。 bSn={O"M  
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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。 K9Onjs%U  
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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。 wWSw0 H/  
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视网膜的散射 .3jijc j  
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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。 0M)\([W9&  
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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。 S6\E  I5S  
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脚本 vl6|i)D  
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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： eu8a<  
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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。 ("{vbs$;  
余下的脚本计算与屈光度有关的所有参数。 c6=XJvz  
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分析 Z-pZyDz  
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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。 @HnahD  
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脚本代码 Cs,Cb2[  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. PMX'vA`  
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Dim entity As T_ENTITY \VI0/G)L
 
Dim op As T_OPERATION H#WqO<<v  
Dim mat As T_MODELMATERIAL aIr"!. 4  
Dim A As Double =3rf}bl2  
Dim pupilDiam As Double j|qdf3^f  
Dim eID As Long %Wm)  
Dim parID As Long EZVgTySd  
Dim count As Integer ?B)e8i<[f  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double ~(NFjCUY?  
Dim tlens As Double, nlens As Double 8Fbt >-N<\  
Dim curv As Double, conic As Double wr(*RI"  
Dim ok As Long O3dQno  
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Sub Main *lu*h&Y  
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    '用户输入对话框 ,J<+Wxz  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 m(1ot M9  
        TextBox 220,21,40,21,.TextBox1 'default: 0 F x$W3FIO]  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 aI}htb{m`  
        OKButton 40,91,90,21 M1k_ldP  
        CancelButton 190,91,90,21  BPKrRex  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 OwgPgrV  
        TextBox 220,49,40,21,.TextBox2 'default: 4 /qq*"R  
    End Dialog - K"L6m|  
    Dim dlg As UserDialog _5p]Arg?}&  
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    ok = Dialog (dlg) 7TU77  
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    If ok=0 Then    'cancel button was pressed !c0x^,iE  
        Print "Execution cancelled." X'%BS  
        End >}C:EnECy  
    End If muBl~6_mb2  
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    'Assign accommodation and pupil diameter & use defaults if field left empty hv#LKyp%  
    If dlg.TextBox1 = "" Then "]=XB0)  
        A = 0           'Default accommodation <]#_&Na  
    Else _W,?_"[R=  
        A = CDbl(dlg.TextBox1) _g D9oK  
    End If ycEp,V;[Z  
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    If dlg.TextBox2 = "" Then sebuuL.l0<  
        pupilDiam = 4   'Default pupil diameter 1-<?EOYaE  
    Else Wh"xt:  
        pupilDiam = CDbl(dlg.TextBox2) YluvWHWi  
    End If >m=
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    Print " " D$D;'Kij  
    Print "Accommodation = " & A & " Diopters" ,w
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    Print "Pupil Diameter = " & pupilDiam & " mm" <iH"5DEe  
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    ' Calculate new parameters with accommodation mM+^v[=  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness o?3C-A|  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens {n<1uh9~$8  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens  3L4v@  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens |OZ>
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    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens >{rD3X"d  
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    tlens = 3.767 + 0.04*A                  'Lens thickness JiXN"s^mcb  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction Cs,t:aj
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    'Adjust parameters to account for accommodation 9om}j
  
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    '************************************************************************* sd*NY  
    'Aqueous thickness (Position of Lens) w'mn O'%  
    '************************************************************************* [LbCG  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) wc}4:~  
    GetCustomElement eID, entity 1=~##/at  
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    parID = FindFullName( "Geometry.Arizona Eye" ) SuBUhzR  
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    ' Delete any shift(s) in z t-]~^s  
    count = 0 N'21I$D  
    While GetOperationCount(eID)>count A2`Xh#o  
        GetOperation eID, count, op |~Vq"6`  
        If op.Type="ShiftZ" Then _sCzee&uQ  
            DeleteOperation eID,count _M
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            count=count-1 S3c%</'  
        End If o'YK\L!p  
        count=count+1 Dd)L~`k{)  
    Wend edlsS}8^  
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    'Set new shift in U-q:Y-
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    op.Type = "ShiftZ" N'%l/  
    op.val1 = taq -e*(+  
    op.parent = parID /86PqKU(P  
    AddOperation eID, op 9tCF m.m  
    Print "Set aqueous humor thickness = " & taq-0.55 7X.B  
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    '************************************************************************* iR'Pc3  
    'Radius and conic constant of anterior lens zZPXI&,  
    '************************************************************************* 9t&m\J >8;  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) ]sB%j@G  
    GetConic eID, entity, curv, conic KU.F4I8}q  
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    SetConic eID, entity, 1/Rant, CCant >WY\P4)k  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant __-V_(/b,x  
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    '************************************************************************* (:7Z-V2(  
    'Radius and conic constant of posterior lens HQ/ Q"  
    '************************************************************************* 7x(z  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) kY~o3p<  
    GetConic eID, entity, curv, conic -8Uz8//A  
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    SetConic eID, entity, 1/Rpost, CCpost )Tf,G[z&ge  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost _%PEv{H0.  
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    '************************************************************************* bN>|4hS  
    'Lens thickness (Position of posterior lens surface) GbBz;ZV%z,  
    '************************************************************************* q_h/zPuH'  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) JZoH -  
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    ' Delete any z-shift(s) p+xjYU4^C  
    count = 0 j\uPOn8k  
    While GetOperationCount(eID)>count g6;a2  
        GetOperation eID, count, op XWf1c ~J  
        If op.Type="ShiftZ" Then A04E <nr  
            DeleteOperation eID,count DG 6W ^  
            count=count-1 :qK^71gz  
        End If dZ,~yV  
        count=count+1 e]3b0`E  
    Wend RJ$x{$r[  
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    'Set new z-shift rSNaflYAr  
    op.Type = "ShiftZ" 4+B OS ~  
    op.val1 = tlens 4cJka~  
    op.parent = parID s)7sgP  
    AddOperation eID, op T1YbF/M'  
    Print "Set lens thickness = " & tlens )'ax
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    '************************************************************************* PsyXt5Dk  
    'Lens index of refraction m4'x>Z  
    '************************************************************************* }x?2txuu  
    eID = FindMaterial( "Lens" ) .=/TT|eMS  
    GetModelMaterial eID, mat pLsWy&G  
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    mat.Nd = nlens Ydh+iLjhx  
    SetModelMaterial eID, mat h0zv@,u  
    Print "Set lens index of refraction = " & nlens ]Jx_bs
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    '************************************************************************* kZ<"hsh,Y'  
    'Pupil diameter 1p COLC%1  
    '*************************************************************************
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    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) Kb*X2#;*  
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    'Adjust pupil diameter (trimming volume inner hole) )~ghb"K  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" K]C@seF`  
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    ' Adjust pupil location to just in front of the lens oaM3#QJ  
    parID = FindFullName( "Geometry.Arizona Eye" ) L31#v$
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    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) #;F*rJ[XY  
    count = 0 lD@`xq.M;  
    While GetOperationCount(eID)>count *QP+p,L*  
        GetOperation eID, count, op 6w4}4i  
        If op.Type="ShiftZ" Then e>!=)6[*  
            DeleteOperation eID,count E}8wnrxf  
            count=count-1 ExZ|_7^<  
        End If ?j@(1",=&  
        count=count+1 w ;xbQZ|+  
    Wend +$\/HO  
    op.Type = "ShiftZ" +VRM:&  
    op.val1 = taq-0.01 X.J$ 5b  
    op.parent = parID 3\0,>L9ET@  
    AddOperation eID, op >A ?,[p`<  
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    Print "Set pupil diameter = " & pupilDiam K)s{D]B  
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    'Update AZ Eye subassembly Description y.Y;<UGu  
    eID = FindFullName( "Geometry.Arizona Eye" ) 0c$ ')`!m  
    GetEntity eID, entity P|QM0GI  
    entity.Description = "Accommodation = " & A & "D" b+e9Pi*\  
    SetEntity eID, entity i{4J$KT  
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    Update ?[c{pb,|  
    Print "DONE!" ,<!v!~Iy  
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End Sub *`~]XM@H  
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如果屈光度是4，光瞳直径是4，则会输出如下数据： s|9[=JMG  
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Accommodation = 4 Diopters ANq3r(  
Pupil Diameter = 4 mm IT:8k5(L5j  
Set aqueous humor thickness = 2.81 kKz>
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Set anterior lens radius = 10.4 and conic constant = -2.375869 nr- 32u  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 Fb\ E39  
Set lens thickness = 3.927 J)._&O$  
Set lens index of refraction = 1.42672 b&2N7%  
Set pupil diameter = 4 k
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DONE! KK, t!a