[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。 SB1\SNB  
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模型 *K6 V$_{S  
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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。 7Cz
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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. CE>RAerY  
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光源 y(B~)T~e@  
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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。 ^IuHc_  
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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。 ^{["]!f#  
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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。 inavi5.  
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视网膜的散射 HHD4#XcU  
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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。 W{l+_a{/9  
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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。 !mrB+<:  
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脚本 0 ]U ;5  
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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： Gd`qZqx#  
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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。 "?V4Tl~uu  
余下的脚本计算与屈光度有关的所有参数。 ; )O)\__"-  
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分析 JQ'NFl9<  
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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。 @0?Mwy!  
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脚本代码  pzezN  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. m,$oV?y>j  
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Dim entity As T_ENTITY ~" B0P>7  
Dim op As T_OPERATION RyC]4QyC  
Dim mat As T_MODELMATERIAL |&3m'"(  
Dim A As Double 5[esW  
Dim pupilDiam As Double 9zEO$<e o  
Dim eID As Long oDTt+b  
Dim parID As Long 07Yh  
Dim count As Integer LCK  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double \y{Bnp5h  
Dim tlens As Double, nlens As Double x SF#ys4v  
Dim curv As Double, conic As Double C 7YZ;{t  
Dim ok As Long gzvEy^X  
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Sub Main P*T'R  
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    '用户输入对话框 wt[MzpRP  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 ,<%Y.x%4z[  
        TextBox 220,21,40,21,.TextBox1 'default: 0 ?3kfhR  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 RO=[Rr!   
        OKButton 40,91,90,21 g4&zBn  
        CancelButton 190,91,90,21 9`i=kp  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 .B{3=z^  
        TextBox 220,49,40,21,.TextBox2 'default: 4 BHOxwW{  
    End Dialog MQ5#6vJ  
    Dim dlg As UserDialog [Oe$E5qv)]  
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    ok = Dialog (dlg) C[gCwDwl  
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    If ok=0 Then    'cancel button was pressed !`hjvJryw  
        Print "Execution cancelled." =|bM|8,  
        End m.EI("n"J  
    End If XL>Vwd  
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    'Assign accommodation and pupil diameter & use defaults if field left empty q-eC=!#}  
    If dlg.TextBox1 = "" Then /$'tO3  
        A = 0           'Default accommodation 1mgLH  
    Else #+|{l*>  
        A = CDbl(dlg.TextBox1) |8c3%jve  
    End If vr/V_  
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    If dlg.TextBox2 = "" Then a[]=*(AZI  
        pupilDiam = 4   'Default pupil diameter GN?^7kI  
    Else di>"\On-  
        pupilDiam = CDbl(dlg.TextBox2) ?P
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    End If y/h~oGxy  
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    Print " " UGj!I  
    Print "Accommodation = " & A & " Diopters" @bOhnd#W  
    Print "Pupil Diameter = " & pupilDiam & " mm" 1T!b#x4  
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    ' Calculate new parameters with accommodation hU3c;6]3  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness fQ=Yf?b  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens @ U'g}K  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens B/:q  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens *r@7:a5  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens B BbGq8p  
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    tlens = 3.767 + 0.04*A                  'Lens thickness fPZt*A__  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction F$ShhZgi  
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    'Adjust parameters to account for accommodation ci0)kxUBF  
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    '************************************************************************* c [sydl  
    'Aqueous thickness (Position of Lens) 5,}
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    '************************************************************************* -;20|US)u  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) ^=.R#zrc  
    GetCustomElement eID, entity L3GA]TIf  
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    parID = FindFullName( "Geometry.Arizona Eye" ) 'FgBYy/
 
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    ' Delete any shift(s) in z zflfV!vAg  
    count = 0 t6m3lq{  
    While GetOperationCount(eID)>count dKTyh:_{  
        GetOperation eID, count, op de1cl<  
        If op.Type="ShiftZ" Then U>w#`Sy[  
            DeleteOperation eID,count #<s6L"Z-  
            count=count-1 ~7+7{9g  
        End If T$%r?p(s  
        count=count+1 Atc9[<~WG  
    Wend 5.5<.")  
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    'Set new shift in !iA3\
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    op.Type = "ShiftZ" v_mk{  
    op.val1 = taq ^MIF+/bQ  
    op.parent = parID cWjb149@)  
    AddOperation eID, op 7rQwn2XD{  
    Print "Set aqueous humor thickness = " & taq-0.55 =!)Ye:\Q  
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    '************************************************************************* a?jUm.  
    'Radius and conic constant of anterior lens YbtsJ <w  
    '************************************************************************* :dq.@:+<R  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) L#O1>  
    GetConic eID, entity, curv, conic waI?X2  
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    SetConic eID, entity, 1/Rant, CCant IR;l{q&`  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant :B{Wf 2<z  
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    '************************************************************************* :No`+X[Kq  
    'Radius and conic constant of posterior lens )Tjh  
    '************************************************************************* fh_+M"Y0`  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) Lh%z2 5t  
    GetConic eID, entity, curv, conic }py)EI,U  
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    SetConic eID, entity, 1/Rpost, CCpost ]H|O  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost c?5?TJpm  
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    '************************************************************************* A12EUr5$  
    'Lens thickness (Position of posterior lens surface) A,67)li3  
    '************************************************************************* 9gq+,g>E_  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) m%zo? e  
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    ' Delete any z-shift(s) yPY}b_W  
    count = 0 mi[t1cN)=  
    While GetOperationCount(eID)>count )5T82=[h<  
        GetOperation eID, count, op e}dGK=`  
        If op.Type="ShiftZ" Then .3 >"qv  
            DeleteOperation eID,count
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            count=count-1 F>Pr`T?>  
        End If a-e_
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        count=count+1 "s-3226kj  
    Wend LMKhtOZ?  
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    'Set new z-shift v[;R(pt?  
    op.Type = "ShiftZ" srPczVG*  
    op.val1 = tlens )<Fq}Q86  
    op.parent = parID /RVwhA+c  
    AddOperation eID, op PRJ  
    Print "Set lens thickness = " & tlens ~c,CngeL0  
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    '************************************************************************* e5RF6roxO  
    'Lens index of refraction &F- \t5X=i  
    '************************************************************************* ai%*s&0/Y  
    eID = FindMaterial( "Lens" ) d|#&j."  
    GetModelMaterial eID, mat )ifjK6*  
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    mat.Nd = nlens p{ Xde   
    SetModelMaterial eID, mat }7non  
    Print "Set lens index of refraction = " & nlens dx@|M{jz'  
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    '************************************************************************* f=k_U[b4>  
    'Pupil diameter OZc4 -5  
    '************************************************************************* 8)lrQvZ  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) 3d
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    'Adjust pupil diameter (trimming volume inner hole) +0}z3T1L  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" SZ29B  
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    ' Adjust pupil location to just in front of the lens SJB^dI**/d  
    parID = FindFullName( "Geometry.Arizona Eye" ) y2W|,=Vd  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) /#WvC;B  
    count = 0 @(bg#  
    While GetOperationCount(eID)>count aFaioE#h(  
        GetOperation eID, count, op ({ O~O5k  
        If op.Type="ShiftZ" Then 7fI2b,~  
            DeleteOperation eID,count 0G31Kou  
            count=count-1 NbC
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        End If 7u{V1_n1  
        count=count+1 fat;5XL@  
    Wend #c!rx%8I  
    op.Type = "ShiftZ" @R-11wP)M  
    op.val1 = taq-0.01 [~PR\qm  
    op.parent = parID 5(gWK{R)*  
    AddOperation eID, op z&cM8w:  
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    Print "Set pupil diameter = " & pupilDiam t~7OtPF  
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    'Update AZ Eye subassembly Description
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    eID = FindFullName( "Geometry.Arizona Eye" ) qA;Gl"HF  
    GetEntity eID, entity QChncIqc  
    entity.Description = "Accommodation = " & A & "D" Esu{c9,  
    SetEntity eID, entity ta6>St7.  
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    Update eTFep^[  
    Print "DONE!" /ej[oR  
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End Sub W]oa7
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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： 
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Accommodation = 4 Diopters (H5#r2h%Y
 
Pupil Diameter = 4 mm :hT.L3n,  
Set aqueous humor thickness = 2.81 J/fnSy  
Set anterior lens radius = 10.4 and conic constant = -2.375869 Jz=|-F(Sy  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 F^$;hMh%  
Set lens thickness = 3.927 IITUM)  
Set lens index of refraction = 1.42672 a2Nxpxho  
Set pupil diameter = 4 =[8K#PZ$w  
DONE! 5x%Blkx