[技术]Arizona眼睛模型 [复制链接]

简介 WHvU|rJ  
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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。 YUsMq3^&  
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模型 j9/Ev]im|F  
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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。 DX%D8atrr  
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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. Qv>rww]  
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光源 N
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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。 W;@9x1jKX  
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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。 .WT^L2l%  
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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。 zS+_6s  
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视网膜的散射 [Y=X^"PF  
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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。 -*r]9f6x  
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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。 Om=*b#k  
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脚本 +|=5zWI/  
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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： 9x40  
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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。 p&#*  
余下的脚本计算与屈光度有关的所有参数。 WgK|r
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分析 :&oUI&(o  
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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。 {k}EWV  
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脚本代码 J|BZ{T}d  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. X)TUKt  
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Dim entity As T_ENTITY S=wJ{?gzAK  
Dim op As T_OPERATION ]O;Hlty(g  
Dim mat As T_MODELMATERIAL 2i@t;h2E  
Dim A As Double AIXvS*Y,  
Dim pupilDiam As Double 96.z\[0VZ  
Dim eID As Long X0.-q%5  
Dim parID As Long 3koXM_4_{)  
Dim count As Integer 7q] @Jx9  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double Twj?SV  
Dim tlens As Double, nlens As Double ;5.o;|w?!  
Dim curv As Double, conic As Double b:iZ.I  
Dim ok As Long P;dp>jL  
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Sub Main iC{~~W6  
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    '用户输入对话框 I'[hvp  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 [?$|   
        TextBox 220,21,40,21,.TextBox1 'default: 0 -|DSfI#j  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 B~u_zZE  
        OKButton 40,91,90,21 /Lc= K<  
        CancelButton 190,91,90,21 /~LXY<-(  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 v^lR]9;  
        TextBox 220,49,40,21,.TextBox2 'default: 4 Vd{h|=J  
    End Dialog p]zYj >e  
    Dim dlg As UserDialog ; YaR|)B  
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    ok = Dialog (dlg) W].P(A
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    If ok=0 Then    'cancel button was pressed ')9%eBaeK  
        Print "Execution cancelled." 4R U1tWQ%  
        End B=;pyhc  
    End If J9LS6~ 7  
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    'Assign accommodation and pupil diameter & use defaults if field left empty toipEp<ci  
    If dlg.TextBox1 = "" Then 3"gifE  
        A = 0           'Default accommodation 4JHQ^i-aY  
    Else LC/w".oq?  
        A = CDbl(dlg.TextBox1) sK:,c5^  
    End If )Q\ZYCPOr  
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    If dlg.TextBox2 = "" Then I_yIVw;  
        pupilDiam = 4   'Default pupil diameter G5Ci"0  
    Else v`hv5wQ  
        pupilDiam = CDbl(dlg.TextBox2) n;"4`6L~  
    End If L!L/QG|wdf  
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    Print " " xLZQ\2q  
    Print "Accommodation = " & A & " Diopters" \QUvImT  
    Print "Pupil Diameter = " & pupilDiam & " mm" ED/-,>[f  
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    ' Calculate new parameters with accommodation 13
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    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness J1<fE(X  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens (nrrzOax  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens skcMGEB  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens 04;y%~,}U/  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens H/V%DO  
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    tlens = 3.767 + 0.04*A                  'Lens thickness P:k(=CzZ@J  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction L>UYR++<6  
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    'Adjust parameters to account for accommodation ud:?~?j&w  
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    '************************************************************************* p8"(z@T  
    'Aqueous thickness (Position of Lens) 8{+~3@T  
    '************************************************************************* fnnwe2aso  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) 1|w,Z+/  
    GetCustomElement eID, entity 73~Mq7~8  
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    parID = FindFullName( "Geometry.Arizona Eye" ) 3r em"M  
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    ' Delete any shift(s) in z [/uKo13  
    count = 0 :e
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    While GetOperationCount(eID)>count qd|*v
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        GetOperation eID, count, op X}zKV  
        If op.Type="ShiftZ" Then M]` Q4\  
            DeleteOperation eID,count #
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            count=count-1 .%wEuqW=0  
        End If ]bnxOk  
        count=count+1 rF0zGNH  
    Wend \wRr6
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    'Set new shift in -N\{QX1Yd  
    op.Type = "ShiftZ" 3n:<oOV  
    op.val1 = taq CJKH"'u3^  
    op.parent = parID j|G-9E  
    AddOperation eID, op , D1[}Lr=K  
    Print "Set aqueous humor thickness = " & taq-0.55 RO.(k!J .  
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    '************************************************************************* M<$l&%<`G  
    'Radius and conic constant of anterior lens 4\OELU  
    '************************************************************************* <Z8] W1)  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) F[=m|MZb  
    GetConic eID, entity, curv, conic @&ZTEznbyt  
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    SetConic eID, entity, 1/Rant, CCant jATU b-  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant ?ha}&##  
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    '************************************************************************* rFy9K4D  
    'Radius and conic constant of posterior lens ygfqP  
    '************************************************************************* Fc
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    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) c&Zm>Qo[  
    GetConic eID, entity, curv, conic oNU* q.Q  
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    SetConic eID, entity, 1/Rpost, CCpost 17i^|&J6}:  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost ;%Da {  
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    '************************************************************************* GO)rpk9  
    'Lens thickness (Position of posterior lens surface) BkZ%0rw%  
    '************************************************************************* `
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) tJu<#hX  
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    ' Delete any z-shift(s) ,?d%&3z<a  
    count = 0 |fI%L9  
    While GetOperationCount(eID)>count Ksp;bfe  
        GetOperation eID, count, op R]Yhuo9,&n  
        If op.Type="ShiftZ" Then nDOIE)#  
            DeleteOperation eID,count Y@4vQm+  
            count=count-1 )ED[cYGx  
        End If hrL<jcv|  
        count=count+1 V0AX1?H~w  
    Wend m5p~>]}fYF  
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    'Set new z-shift i
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    op.Type = "ShiftZ" `?@7 KEl>  
    op.val1 = tlens W^N"y&  
    op.parent = parID piG1&*  
    AddOperation eID, op $ B9=v  
    Print "Set lens thickness = " & tlens Yq^y"rw  
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    '************************************************************************* JgB# EoF  
    'Lens index of refraction ~?&ijhZ  
    '************************************************************************* fA8
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    eID = FindMaterial( "Lens" ) /)I9+s#q9o  
    GetModelMaterial eID, mat X2uX+}h*tA  
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    mat.Nd = nlens 7asq]Y}<  
    SetModelMaterial eID, mat R,\ r{@yrz  
    Print "Set lens index of refraction = " & nlens $aA.d^  
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    '************************************************************************* VL{#.;QQa  
    'Pupil diameter HIq1/)  
    '************************************************************************* <C$<(Dw5  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) qj6`nbZ{va  
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    'Adjust pupil diameter (trimming volume inner hole) }SV3PdE  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" ]1&9~TL  
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    ' Adjust pupil location to just in front of the lens `0^i #  
    parID = FindFullName( "Geometry.Arizona Eye" ) Vi#im`@  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) YP<]f>SBt  
    count = 0 cWc)sb  
    While GetOperationCount(eID)>count T,uIA]  
        GetOperation eID, count, op DH !Br  
        If op.Type="ShiftZ" Then +_eb*Z`5o  
            DeleteOperation eID,count ?Qig$  
            count=count-1 psC7IE<v  
        End If WO-WoPO  
        count=count+1 6EU4  
    Wend (g m^o{  
    op.Type = "ShiftZ" 4c=kT@=jX  
    op.val1 = taq-0.01 WQpJd7
  
    op.parent = parID uC(S`Q[Bg  
    AddOperation eID, op g8+,wSE  
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    Print "Set pupil diameter = " & pupilDiam pYVy(]1I(3  
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    'Update AZ Eye subassembly Description ? ~
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    eID = FindFullName( "Geometry.Arizona Eye" ) ?Q)Z..7  
    GetEntity eID, entity udGGDH  
    entity.Description = "Accommodation = " & A & "D" k_n{Mss'9  
    SetEntity eID, entity 0lCd,a2:  
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    Update #`4^zU)  
    Print "DONE!" %-/:ps  
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End Sub f*vk1dS:*3  
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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： 9yo[T(8  
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Accommodation = 4 Diopters :EwA$`/  
Pupil Diameter = 4 mm T(UYlLe  
Set aqueous humor thickness = 2.81 1K9?a;.  
Set anterior lens radius = 10.4 and conic constant = -2.375869 }pnFJ  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 3cO[t\/up  
Set lens thickness = 3.927 W 'a~pB1I  
Set lens index of refraction = 1.42672 WlQ=CRY  
Set pupil diameter = 4 KOEi_9i}  
DONE! )75yv<L2S,