[技术]Arizona眼睛模型 [复制链接]

简介 6$kqa
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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。 3Dng1}  
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模型 $*e2YQdLo  
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模型的定义如表1种所示，由半径、圆锥常数、折射率、阿贝数、到下一面的距离等一系列表面组成。一些参数由屈光度（A）来决定。 Yw^m  
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在FRED中使用0屈光度来创建的，光瞳加在了透镜的前面。材料是创建一个新的材料并选择类型“Model Material”,输入的参数是nd和vd. Y$Zx,  
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光源 ~Sj9GxTe  
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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。 vHyC;4'  
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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。 11o.c;  
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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。 3EJj9}#x"'  
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视网膜的散射 K"|l@Q[  


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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。  _zY#U9  
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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。 Cn,d?
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脚本 @$ne{2J3  
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内置脚本使用对话框显示屈光度和光瞳直径的数值设置。使用FRED Basic脚本创建和使用对话框非常容易。图6显示了如何获取用户自定义对话框，如下图所示： 8EW_V$>R  
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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。 CDsSrKhx  
余下的脚本计算与屈光度有关的所有参数。 ZInpMp  
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分析 &5\iM^
 
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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。 7?#J~.d5  
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脚本代码 uZNTHD
 
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. %'bM){  
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Dim entity As T_ENTITY joFm]3$;  
Dim op As T_OPERATION V3&RJ k=b  
Dim mat As T_MODELMATERIAL [)H&
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Dim A As Double y&6FybIz  
Dim pupilDiam As Double WffQ:L?  
Dim eID As Long <fZyAa3}  
Dim parID As Long 9Vg?{v!yn  
Dim count As Integer S=MEG+Ad  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double Njxv4cc  
Dim tlens As Double, nlens As Double /Gd=n  
Dim curv As Double, conic As Double ~5NXd)2+Ks  
Dim ok As Long $mu^G t  
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Sub Main R cAwrsd  
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    '用户输入对话框 Lb!Fcf|h  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 |z9*GY6RU  
        TextBox 220,21,40,21,.TextBox1 'default: 0 .k#U]M  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 '9laa=H%8  
        OKButton 40,91,90,21 2y//
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        CancelButton 190,91,90,21 r/YMLQ  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 y`VyQWW  
        TextBox 220,49,40,21,.TextBox2 'default: 4 vq0Vq(V=  
    End Dialog q8FTi^=Kb  
    Dim dlg As UserDialog aT{_0m$G10  
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    ok = Dialog (dlg) v_<rNc,z-s  
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    If ok=0 Then    'cancel button was pressed *T-<|zQ  
        Print "Execution cancelled." )Lk639r  
        End HguT"%iv  
    End If Vy6qbC-Kt  
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    'Assign accommodation and pupil diameter & use defaults if field left empty 6hw=  
    If dlg.TextBox1 = "" Then oQLq&zRH`f  
        A = 0           'Default accommodation &TnS4O  
    Else \RNNg  
        A = CDbl(dlg.TextBox1) A}BVep@D  
    End If _Us#\+]_:  
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    If dlg.TextBox2 = "" Then O[\iE5+$  
        pupilDiam = 4   'Default pupil diameter aAZZ8V  
    Else cm&nd'A't  
        pupilDiam = CDbl(dlg.TextBox2) PxTwPl  
    End If <Q3oT  
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    Print " " }K7#Q  
    Print "Accommodation = " & A & " Diopters" +Jlay1U&  
    Print "Pupil Diameter = " & pupilDiam & " mm" yg`j-9[8  
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    ' Calculate new parameters with accommodation X@'uy<tI-  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness Ye\rB\-  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens c-x,fS"&W  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens bbtGXfI+SB  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens J}*,HT*  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens H7?Vybg~  
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    tlens = 3.767 + 0.04*A                  'Lens thickness 7yG#Z)VE  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction "$~':) V"  
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    'Adjust parameters to account for accommodation 0m7Y>0wC6T  
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    '************************************************************************* S$f9m  
    'Aqueous thickness (Position of Lens) #Z}Rfk(~  
    '************************************************************************* w~.f  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) 45=bGf#  
    GetCustomElement eID, entity aFc1|.Nm  
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    parID = FindFullName( "Geometry.Arizona Eye" ) }^4Xv^dW>g  
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    ' Delete any shift(s) in z ?# Mr  
    count = 0 d)B@x`  
    While GetOperationCount(eID)>count bADnW4N`6;  
        GetOperation eID, count, op H;D>|q  
        If op.Type="ShiftZ" Then Av @b!iw+  
            DeleteOperation eID,count Jz?j[  
            count=count-1 \@-@Y  
        End If _f
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        count=count+1 ~fBtQGdX  
    Wend +ylTGSZS  
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    'Set new shift in n?oW< &  
    op.Type = "ShiftZ" 1da@3xaF  
    op.val1 = taq JBD7h5|Lc  
    op.parent = parID _geWE0 E  
    AddOperation eID, op A]y`7jJ  
    Print "Set aqueous humor thickness = " & taq-0.55 'QG xd!4  
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    '************************************************************************* 68bQ;Dv  
    'Radius and conic constant of anterior lens Q0$8j-1I  
    '************************************************************************* :fKl]XO  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) V @rI`~$  
    GetConic eID, entity, curv, conic ,4hJT  
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    SetConic eID, entity, 1/Rant, CCant pb^i^tA+A  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant 2^XGGB0  
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    '************************************************************************* iz5CAxm  
    'Radius and conic constant of posterior lens 9*$t!r{B@  
    '*************************************************************************  ,t}vz 7  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) cD@(/$wt  
    GetConic eID, entity, curv, conic qsL)}sC^8  
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    SetConic eID, entity, 1/Rpost, CCpost 1pQn8[sc@  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost E"\/M  
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    '************************************************************************* \:R%4w#Jv  
    'Lens thickness (Position of posterior lens surface) t4{rb, }W  
    '************************************************************************* #XK2Ien)Z  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) D@
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    ' Delete any z-shift(s) z,|r*\dw  
    count = 0 BW-`t-,E;  
    While GetOperationCount(eID)>count /{|EAd{  
        GetOperation eID, count, op UsgK  
        If op.Type="ShiftZ" Then 85lCj-cs  
            DeleteOperation eID,count Z/Eb:  
            count=count-1 u,F nAh?"  
        End If >d~WH@o`G  
        count=count+1 ]&?Y~"{cD  
    Wend 6\L0mcXR!  
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    'Set new z-shift 0YaA`  
    op.Type = "ShiftZ" @*>@AFnf\Z  
    op.val1 = tlens _AYXc] 4%  
    op.parent = parID b6W2^tr-  
    AddOperation eID, op "ZHW2l Mf  
    Print "Set lens thickness = " & tlens _4TH4~cY  
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    '************************************************************************* -g)9R%>
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    'Lens index of refraction $m7?3/YG  
    '************************************************************************* )64@2~4y  
    eID = FindMaterial( "Lens" ) a-y+@#;2_  
    GetModelMaterial eID, mat dG@"!!,  
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    mat.Nd = nlens vQ<90ZxqB  
    SetModelMaterial eID, mat f5F@^QXQ  
    Print "Set lens index of refraction = " & nlens l6(-I Tb  
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    '************************************************************************* whonDG4WP  
    'Pupil diameter .tkT<o-u<J  
    '************************************************************************* lW<PoT  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) m7&O9?X  
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    'Adjust pupil diameter (trimming volume inner hole) A3vUPWdDk  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" d\%WgH  
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    ' Adjust pupil location to just in front of the lens 79nG|Yj|\  
    parID = FindFullName( "Geometry.Arizona Eye" ) U;bK!&Z  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) 6}75iIKi  
    count = 0 <$6QDfa#  
    While GetOperationCount(eID)>count ^BUYjq%(`  
        GetOperation eID, count, op =81@o,1w  
        If op.Type="ShiftZ" Then F&])P- !3  
            DeleteOperation eID,count 0~HKiH-  
            count=count-1 6``'%S'#  
        End If wx\v:A  
        count=count+1 @lCJ G!u  
    Wend e`d%-9  
    op.Type = "ShiftZ" [v$0[IuY,  
    op.val1 = taq-0.01 "oWwc zzO  
    op.parent = parID !E,A7s  
    AddOperation eID, op !h(|\" }  
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    Print "Set pupil diameter = " & pupilDiam kgy:Q'  
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    'Update AZ Eye subassembly Description S5KEXnjm  
    eID = FindFullName( "Geometry.Arizona Eye" ) HODz*pI  
    GetEntity eID, entity V?Z.\~
 
    entity.Description = "Accommodation = " & A & "D" >RPd$('T  
    SetEntity eID, entity \ W?R  
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    Update Ob}?zl@  
    Print "DONE!" 9Rn? :B~W:  
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End Sub 0`)iIz  
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如果屈光度是4，光瞳直径是4，则会输出如下数据： b3S.-W{p.  
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Accommodation = 4 Diopters {g2@6ct  
Pupil Diameter = 4 mm fBgEnz/  
Set aqueous humor thickness = 2.81 nt;haeJ  
Set anterior lens radius = 10.4 and conic constant = -2.375869 _$wmI/_JM  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 <EPj$::  
Set lens thickness = 3.927 &ZghMq~  
Set lens index of refraction = 1.42672 NB\{'  
Set pupil diameter = 4 CNQC^d\ h  
DONE! B.g[c97