[技术]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。 |;(P+Q4lB  
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模型 |"KdW#.x  
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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。 FIAmAZH}_  
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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.
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光源 !B#lZjW#  
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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。 c;(Fz^&_  
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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。 9An\uH)mL  
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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。 FqGMHM\J  
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视网膜的散射 I`jG  
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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。 Y}q~Km  
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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。 2?:OsA}  
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脚本 v+trHdSBYE  
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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： =TzJgx  
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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。 u#y)+A2&!  
余下的脚本计算与屈光度有关的所有参数。 r}Gku0Hu_E  
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分析 {%P2.:  
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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。 #4"eQ*.*"  
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脚本代码 1gt 7My  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. 8:*ZuR|~  
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Dim entity As T_ENTITY vpdPW%B  
Dim op As T_OPERATION 9`VY)"rJ  
Dim mat As T_MODELMATERIAL QuI!`/N)z  
Dim A As Double rFm?Bu  
Dim pupilDiam As Double ^'Rs`e  
Dim eID As Long >\J<`  
Dim parID As Long ![vy{U.:`  
Dim count As Integer $nIE;idk  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double &m9= q|;m  
Dim tlens As Double, nlens As Double \h0+` ;Q  
Dim curv As Double, conic As Double q@VIFmqY!  
Dim ok As Long ;p<BiC$b  
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Sub Main Vu4LC&q  
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    '用户输入对话框 EKN<KnU%  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 ]-a
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        TextBox 220,21,40,21,.TextBox1 'default: 0 'gD./|Z0  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 ,VUOsNN4\  
        OKButton 40,91,90,21 n
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        CancelButton 190,91,90,21 >f-RzQ k  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 d|~'#:y@  
        TextBox 220,49,40,21,.TextBox2 'default: 4 on5\rY<I:@  
    End Dialog gXn`!  
    Dim dlg As UserDialog k$#1T +(G  
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    ok = Dialog (dlg) M)wNu  
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    If ok=0 Then    'cancel button was pressed k!$$ *a*  
        Print "Execution cancelled." E(1G!uu<  
        End |DVFi2  
    End If Ic&YiATj  
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    'Assign accommodation and pupil diameter & use defaults if field left empty -y3[\zNe  
    If dlg.TextBox1 = "" Then };Df ><  
        A = 0           'Default accommodation Pd `
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    Else ,qV7$u  
        A = CDbl(dlg.TextBox1) fT?m~W^  
    End If >lek@euqw  
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    If dlg.TextBox2 = "" Then oz|+{b}%  
        pupilDiam = 4   'Default pupil diameter 9q&~!>lt  
    Else WHLTJ]OB  
        pupilDiam = CDbl(dlg.TextBox2) %=s2>vv9  
    End If .>_%12>  
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    Print " " ]ERAt^$0  
    Print "Accommodation = " & A & " Diopters" M9~'dS'XI  
    Print "Pupil Diameter = " & pupilDiam & " mm" d]sg9`  
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    ' Calculate new parameters with accommodation Dd, &a  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness NQiu>Sg  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens P~x4h{~Gd  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens XC}2GHO<  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens z`u$C+Ov  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens wk^$DM/KJ)  
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    tlens = 3.767 + 0.04*A                  'Lens thickness =t~]@?]1D  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction 5dX0C  
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    'Adjust parameters to account for accommodation *`Ge8?qC  
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    '************************************************************************* K>\v<!%a  
    'Aqueous thickness (Position of Lens) j!0-3YKv  
    '************************************************************************* GQjU="+  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) I.SMn,N  
    GetCustomElement eID, entity q!h'rX=_-  
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    parID = FindFullName( "Geometry.Arizona Eye" ) rV-Xsf7Z  
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    ' Delete any shift(s) in z /:,}hy+U  
    count = 0 p"*xyex  
    While GetOperationCount(eID)>count 3lS1WA  
        GetOperation eID, count, op =dWqB&  
        If op.Type="ShiftZ" Then )! kl:  
            DeleteOperation eID,count `bLJwJ7  
            count=count-1 ;vk>k0S  
        End If XN3'k[  
        count=count+1 XF@34b5(  
    Wend 0juP"v$C>  
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    'Set new shift in 9El{>&Fs4  
    op.Type = "ShiftZ" ]&='E.f  
    op.val1 = taq T/hz23nH  
    op.parent = parID F"23vG>3  
    AddOperation eID, op eG
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    Print "Set aqueous humor thickness = " & taq-0.55 I}}>M#  
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    '************************************************************************* 4:s,e<Tc4v  
    'Radius and conic constant of anterior lens 85A7YraL  
    '************************************************************************* a:1$idj  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) 8@FgvWC  
    GetConic eID, entity, curv, conic CRNt5T>qH  
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    SetConic eID, entity, 1/Rant, CCant _0iV6Bj  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant ArT@BqWd  
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    '************************************************************************* \
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    'Radius and conic constant of posterior lens *A0d0M]cg  
    '************************************************************************* [BEQ ~A_I  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) cCG!X%9  
    GetConic eID, entity, curv, conic ow'CwOj$  
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    SetConic eID, entity, 1/Rpost, CCpost Juk'eH2^s  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost sM9
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    '************************************************************************* @$~;vS  
    'Lens thickness (Position of posterior lens surface) 0R-W9qP  
    '************************************************************************* Zb<D%9  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) Y44[2 :m
 
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    ' Delete any z-shift(s) yy`XtJBWWs  
    count = 0 m`tX&K#-  
    While GetOperationCount(eID)>count {]4Zpev  
        GetOperation eID, count, op 8rLhOA  
        If op.Type="ShiftZ" Then u!FF{~5cs  
            DeleteOperation eID,count JI&.d:  
            count=count-1 /3;]e3x  
        End If q{xF7}i  
        count=count+1 `2M*?.vk  
    Wend +Ur75YPh  
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    'Set new z-shift ]na$n[T/I  
    op.Type = "ShiftZ" mPo.Z"uy7  
    op.val1 = tlens Jpn= ^f[rm  
    op.parent = parID j@/p: fk  
    AddOperation eID, op Z~;rp`P  
    Print "Set lens thickness = " & tlens
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    '************************************************************************* vm=d?*cR  
    'Lens index of refraction wZ_"@j<  
    '************************************************************************* LMLrH.  
    eID = FindMaterial( "Lens" ) UC.kI&A  
    GetModelMaterial eID, mat ehZ/J5  
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    mat.Nd = nlens 2g5jGe*0  
    SetModelMaterial eID, mat @=BApuer+  
    Print "Set lens index of refraction = " & nlens xiqeKoAD  
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    '************************************************************************* &_\;p-1:  
    'Pupil diameter C;_00EQ=  
    '************************************************************************* Zlrbd  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) m!3D5z]n9  
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    'Adjust pupil diameter (trimming volume inner hole) 0y2zjXM;3  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" n8i: /ypB  
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    ' Adjust pupil location to just in front of the lens b&RsxW7  
    parID = FindFullName( "Geometry.Arizona Eye" ) 02-% B~oP  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) @h/-P'Lc=7  
    count = 0 z]2lT IWg  
    While GetOperationCount(eID)>count XR$i:kL,,  
        GetOperation eID, count, op i\x@s>@x}  
        If op.Type="ShiftZ" Then BQB<+o'  
            DeleteOperation eID,count C(M?$s`  
            count=count-1 (&X/n=UI  
        End If #L&/o9|  
        count=count+1 G?Za/G  
    Wend % pAbk
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    op.Type = "ShiftZ" 35:R
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    op.val1 = taq-0.01 z|zEsDh;  
    op.parent = parID 4E+8kz'  
    AddOperation eID, op
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    Print "Set pupil diameter = " & pupilDiam |\94a  
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    'Update AZ Eye subassembly Description &}\{qFD;  
    eID = FindFullName( "Geometry.Arizona Eye" ) +x<OyjY5?]  
    GetEntity eID, entity pwV~[+SS_  
    entity.Description = "Accommodation = " & A & "D" s|X_:3\x  
    SetEntity eID, entity _9?v?mL5;  
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    Update 'lOQb)  
    Print "DONE!" nQ{~D5y,,  
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End Sub  ^mN`!+  
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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： \[%_ :9eq  
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Accommodation = 4 Diopters [Mj5o<k;I  
Pupil Diameter = 4 mm 8~g~XUl  
Set aqueous humor thickness = 2.81 U~dqxR"Q  
Set anterior lens radius = 10.4 and conic constant = -2.375869 FtlJ3fB@  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 N,:G5Wx
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Set lens thickness = 3.927 nswhYSX  
Set lens index of refraction = 1.42672 1K'cT\aFm  
Set pupil diameter = 4 nGur2}>n  
DONE! ;Zn&Nc7