[技术]Arizona眼睛模型 [复制链接]

简介 {Vj25Gt  
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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。 B
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模型 fqgm`4>  
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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。 eS{ xma  
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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. [va7+=[1=  
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光源 hm5A@Z   
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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。 6qgII~F'  
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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。 ;<yVJox  
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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。 rLm:qu(F1  
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视网膜的散射 4gNF;  
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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。 #(`@D7S"  
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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。 $*Q_3]AY]  

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脚本 Bi+a)_K  
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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： Z`l97$\  
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如果“OK”按钮按下，将会核对对话框下面的代码行，如果点击取消则脚本终止。然后输入的参数赋予变量，如果此处是保留为空白，则使用默认值。因此，如果没有值输入并点击“OK”按钮，则脚本是以屈光度为0，光瞳直径为4mm来运行的。 Bkn- OG  
余下的脚本计算与屈光度有关的所有参数。 ?CQ\94kO  
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分析 @lau?@$ja  
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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。 ='7n  
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脚本代码 KJwkkCE/=  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. vYD>m~Qc^  
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Dim entity As T_ENTITY P7I,xcOm  
Dim op As T_OPERATION O/IW.t  
Dim mat As T_MODELMATERIAL [G/q*a:K  
Dim A As Double 
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Dim pupilDiam As Double "mAVkq~  
Dim eID As Long sg(L`P  
Dim parID As Long Qhnz7/a9  
Dim count As Integer c?0uv2*Yh  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double #=f ]"uM<  
Dim tlens As Double, nlens As Double "Yn<]Pa_  
Dim curv As Double, conic As Double #4{f2s[j6  
Dim ok As Long ?wps_XU  
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Sub Main @NXGVmY1}  
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    '用户输入对话框 -;z&">  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1
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        TextBox 220,21,40,21,.TextBox1 'default: 0 x7J|  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 hGH{Xp[mW  
        OKButton 40,91,90,21 <ZJ>jZV0*  
        CancelButton 190,91,90,21 >qn@E?Uf  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 HnVUG4yZTD  
        TextBox 220,49,40,21,.TextBox2 'default: 4 {sy#&m(el  
    End Dialog [&rW+/  
    Dim dlg As UserDialog :y'D] ,_  
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    ok = Dialog (dlg) lC6#EU;  
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    If ok=0 Then    'cancel button was pressed #kX=$Bzk  
        Print "Execution cancelled." k6~k  
        End !&C8
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    End If `^s(r>2  
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    'Assign accommodation and pupil diameter & use defaults if field left empty fPHv|_XM>  
    If dlg.TextBox1 = "" Then O'm&S?>  
        A = 0           'Default accommodation F5%-6@=  
    Else  'TV^0D"  
        A = CDbl(dlg.TextBox1) `4Z#/g  
    End If -(>x@];r0  
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    If dlg.TextBox2 = "" Then 5JI+42S \  
        pupilDiam = 4   'Default pupil diameter C9Fc(Y?_  
    Else u *z$I  
        pupilDiam = CDbl(dlg.TextBox2) qo.~5   
    End If Tm_vo-  
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    Print " " 7F3Hkvd[k  
    Print "Accommodation = " & A & " Diopters" 96vv85g  
    Print "Pupil Diameter = " & pupilDiam & " mm" p&_a kQj  
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    ' Calculate new parameters with accommodation Ih`
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    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness YjS|Ht->  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens wH!]B-hn  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens v(<~:]  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens M.d{:&@`%  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens *NDLGdQqz  
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    tlens = 3.767 + 0.04*A                  'Lens thickness [O [N_z  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction `X^4~6/q  
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    'Adjust parameters to account for accommodation  fUb5KCZ  
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    '************************************************************************* #B'WT{B$/~  
    'Aqueous thickness (Position of Lens) 1y_{#,{>  
    '************************************************************************* 4pq>R  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) fQuphMOl6  
    GetCustomElement eID, entity >6ch[W5k@  
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    parID = FindFullName( "Geometry.Arizona Eye" ) ,X\z#B  
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    ' Delete any shift(s) in z EE&~D~yHUL  
    count = 0 6Om-[^  
    While GetOperationCount(eID)>count ?b8NEVjw  
        GetOperation eID, count, op X^9_'T9  
        If op.Type="ShiftZ" Then .1|'9@]lj4  
            DeleteOperation eID,count $j{ynh)^  
            count=count-1 [rPW@|^5  
        End If s/sH",  
        count=count+1 3QUe:8
 
    Wend }tv-  
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    'Set new shift in p$[*GXR4  
    op.Type = "ShiftZ" MQ\:/]a  
    op.val1 = taq r7ywK9UL  
    op.parent = parID uLhamE)  
    AddOperation eID, op A7|"0*62  
    Print "Set aqueous humor thickness = " & taq-0.55 c q3CN@  
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    '************************************************************************* f^%vIB ~[  
    'Radius and conic constant of anterior lens "5dh]-m n  
    '************************************************************************* r*+9<8-ZX<  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) fU)hn  
    GetConic eID, entity, curv, conic M_79\Gz"  
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    SetConic eID, entity, 1/Rant, CCant zy$hDy0  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant X[Y!=e4z  
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    '************************************************************************* IUc!nxF#  
    'Radius and conic constant of posterior lens Sk;IAp#X9  
    '************************************************************************* >%[(C*Cks  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) OIewG5O  
    GetConic eID, entity, curv, conic Mh_jlgE'd#  
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    SetConic eID, entity, 1/Rpost, CCpost TF=S \ Q  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost t'9E~_!C  
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    '************************************************************************* 8<.KWr  
    'Lens thickness (Position of posterior lens surface) T_Y6AII  
    '************************************************************************* %],.?TS2V  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) mH8s'F  
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    ' Delete any z-shift(s) kN]#;R6  
    count = 0 ^x/0*t5};z  
    While GetOperationCount(eID)>count e2B~j3-?z  
        GetOperation eID, count, op z>y,}#D?C  
        If op.Type="ShiftZ" Then &S|laqH  
            DeleteOperation eID,count 0|GxOzNd  
            count=count-1 2_F`ILCML  
        End If h{PLyWH  
        count=count+1 m,up37-{  
    Wend f"-<Z_  
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    'Set new z-shift IRS^F;
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    op.Type = "ShiftZ" ( I,V+v+{Y  
    op.val1 = tlens Y_)04dmr@[  
    op.parent = parID Xq)'p8C?  
    AddOperation eID, op {g )kT_  
    Print "Set lens thickness = " & tlens 5.\!k8a  
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    '************************************************************************* _t;w n7p  
    'Lens index of refraction m CdkYN#  
    '************************************************************************* }%XNB1/`  
    eID = FindMaterial( "Lens" ) t"BpaA^gO  
    GetModelMaterial eID, mat UoKBcarm  
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    mat.Nd = nlens 41C=O@9m  
    SetModelMaterial eID, mat *i$+i  
    Print "Set lens index of refraction = " & nlens /?J_7Lg  
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    '************************************************************************* ^d2g"L   
    'Pupil diameter
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    '************************************************************************* GzR;`,_O/  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) 9td(MZ%i~N  
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    'Adjust pupil diameter (trimming volume inner hole) h2BD?y  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" i&bttSRNV  
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    ' Adjust pupil location to just in front of the lens 49kY]z|"w  
    parID = FindFullName( "Geometry.Arizona Eye" ) hnY^Z_v!  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) Y*AHwc<w`  
    count = 0 6"=e+V@  
    While GetOperationCount(eID)>count T[;{AXLeI  
        GetOperation eID, count, op }h]:I'R!  
        If op.Type="ShiftZ" Then bC@b9opD  
            DeleteOperation eID,count R0=/ Th -  
            count=count-1 om/gk4S2  
        End If Hv IN'  
        count=count+1 '$U"RP^(  
    Wend 4Fz^[L}[  
    op.Type = "ShiftZ" :#|77b0  
    op.val1 = taq-0.01 |mM
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    op.parent = parID t)v#y!Ci"  
    AddOperation eID, op $qEJO=v  
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    Print "Set pupil diameter = " & pupilDiam /y-P)3_  
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    'Update AZ Eye subassembly Description 2
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    eID = FindFullName( "Geometry.Arizona Eye" ) gM=~dBz  
    GetEntity eID, entity HmiwpI  
    entity.Description = "Accommodation = " & A & "D" @a3<fmJ  
    SetEntity eID, entity >H%8~ Oek  
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    Update $zbg  
    Print "DONE!" xGH%4J\  
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End Sub p1D-Q7F  
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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： 9\n}!{@i  
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Accommodation = 4 Diopters AKWw36lm  
Pupil Diameter = 4 mm uL= \t=  
Set aqueous humor thickness = 2.81 0FW=8hFp,  
Set anterior lens radius = 10.4 and conic constant = -2.375869 m[7a~-3:J  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 {:dE_tqo  
Set lens thickness = 3.927 >/n/n{{  
Set lens index of refraction = 1.42672 Vw#07P#A  
Set pupil diameter = 4 2Hd6  
DONE! gGX/p6"