[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。 sI&i{D  
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模型 ;)(Sdf[P  
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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。 b , juF2  
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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. R_Zv'y6  
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光源 |[S90Gw]  
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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。 2+?T66 g  
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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。 %#~((m1  
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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。 ;LCTCt`  
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视网膜的散射 iI5+P`sE&J  
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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。 !^m%O0DT  
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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。 ^Ye\u1n4  
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脚本 !p9)CjQ"  
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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： ~+yZfOcw  
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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。 m9in1RI%  
余下的脚本计算与屈光度有关的所有参数。 zuSq+pxL@  
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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}{'C5  
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脚本代码 k1)%.pt%  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. zN#*G i'  
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Dim entity As T_ENTITY A /(lKq  
Dim op As T_OPERATION 'Gx$Bj  
Dim mat As T_MODELMATERIAL 98RKCc9h  
Dim A As Double a5@z:i  
Dim pupilDiam As Double F]UQuOR)  
Dim eID As Long 3iRA$C-p  
Dim parID As Long As~(7?]r  
Dim count As Integer xl(@C*.sC1  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double =pcF:D#+  
Dim tlens As Double, nlens As Double G O{.9_2  
Dim curv As Double, conic As Double ndink$  
Dim ok As Long 
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Sub Main [U>@,
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    '用户输入对话框 sV/l5]b]  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 N|mJg[j@7  
        TextBox 220,21,40,21,.TextBox1 'default: 0 S${Zzt"  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 Kv37s0|g  
        OKButton 40,91,90,21 ZrO!L_/  
        CancelButton 190,91,90,21 *4S-z&,.c  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 Fk"Ee&H)(  
        TextBox 220,49,40,21,.TextBox2 'default: 4 4[yIOs  
    End Dialog :u6JjW[a)  
    Dim dlg As UserDialog Ej=3/RBsV  
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    ok = Dialog (dlg) eg/<[ A:  
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    If ok=0 Then    'cancel button was pressed .pPm~2]z  
        Print "Execution cancelled." /J3ZL[o?Q  
        End p =(@3%k  
    End If b| M3`  
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    'Assign accommodation and pupil diameter & use defaults if field left empty ~YP Jez  
    If dlg.TextBox1 = "" Then <IJu7t>  
        A = 0           'Default accommodation :i~W }r  
    Else {2&m`Dbm  
        A = CDbl(dlg.TextBox1) yNg9X(U  
    End If 59r_#(uo  
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    If dlg.TextBox2 = "" Then 'sh~,+g  
        pupilDiam = 4   'Default pupil diameter h.eM RdlO  
    Else yWDTjY/  
        pupilDiam = CDbl(dlg.TextBox2) 6at1bQ$  
    End If 7F^#o-@=J  
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    Print " " .zg8i_  
    Print "Accommodation = " & A & " Diopters" Cx<0 H  
    Print "Pupil Diameter = " & pupilDiam & " mm" *
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    ' Calculate new parameters with accommodation \1"'E@+  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness p;T{i._iL  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens *&BnF\?m  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens m: n`g1  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens KRAcnY;u  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens dU)]:>Uz  
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    tlens = 3.767 + 0.04*A                  'Lens thickness #Z+i~t{e(  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction &H}r%%|A  
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    'Adjust parameters to account for accommodation N`@NiJ(O;  
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    '************************************************************************* b-ll  
    'Aqueous thickness (Position of Lens) zGKyN@o  
    '************************************************************************* "@R>J?Cc+  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) {]_uMg#
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    GetCustomElement eID, entity @"
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    parID = FindFullName( "Geometry.Arizona Eye" ) [x=jH>Y  
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    ' Delete any shift(s) in z ~5Pb&+<$  
    count = 0 9.'h^#C  
    While GetOperationCount(eID)>count '* mH*?Y  
        GetOperation eID, count, op ,}oM-B  
        If op.Type="ShiftZ" Then =4V&*go*\  
            DeleteOperation eID,count ^;!0j9"*:  
            count=count-1 ,B?~-2cCz  
        End If glDcUCF3  
        count=count+1 lC:k7<0Ji  
    Wend Lbe\@S  
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    'Set new shift in X%z }VA  
    op.Type = "ShiftZ" ojYbR<jn9  
    op.val1 = taq Gjo
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    op.parent = parID infl.  
    AddOperation eID, op ? WJ> p  
    Print "Set aqueous humor thickness = " & taq-0.55 SJD@&m%?[  
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    '************************************************************************* ~wg:!VWA)  
    'Radius and conic constant of anterior lens zvABU+{jD  
    '************************************************************************* V5+SWXZ  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) coYij  
    GetConic eID, entity, curv, conic " \I4u{zC  
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    SetConic eID, entity, 1/Rant, CCant
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    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant 2,ECYie^  
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    '************************************************************************* ),%6V5a+E  
    'Radius and conic constant of posterior lens oIUy-|  
    '************************************************************************* zD?oXs  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) <ZU=6Hq  
    GetConic eID, entity, curv, conic 3?Y2L  
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    SetConic eID, entity, 1/Rpost, CCpost  hi
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    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost xsWur(>]  
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    '************************************************************************* THmb
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    'Lens thickness (Position of posterior lens surface) SG6sw]x  
    '************************************************************************* ^vG8#A}]  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) Mq';S^  
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    ' Delete any z-shift(s) !w&kyW?e  
    count = 0 oK 6(HF'&  
    While GetOperationCount(eID)>count <n3!{w3<  
        GetOperation eID, count, op CI3XzH\IX*  
        If op.Type="ShiftZ" Then J\e+}{  
            DeleteOperation eID,count AT5aDEb^^  
            count=count-1 DTWD|M  
        End If iNMx"F0r  
        count=count+1 Tw +  
    Wend asJ)4ema  
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    'Set new z-shift m3o,@=b  
    op.Type = "ShiftZ" g-Pwp[!qkf  
    op.val1 = tlens z=$jGL  
    op.parent = parID =4h+ M$2  
    AddOperation eID, op Bn>8&w/P  
    Print "Set lens thickness = " & tlens &+G"k~%  
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    '************************************************************************* b(9FZ]7S  
    'Lens index of refraction 4H@Wc^K  
    '************************************************************************* .^b;osAU  
    eID = FindMaterial( "Lens" ) ^e+
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    GetModelMaterial eID, mat ? w^-  
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    mat.Nd = nlens O]qU[y+  
    SetModelMaterial eID, mat "
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    Print "Set lens index of refraction = " & nlens 41fJ%f` G  
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    '************************************************************************* u ElAnrm  
    'Pupil diameter q4V7  
    '************************************************************************* ?&Pg2]g<  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) P6MRd/y |  
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    'Adjust pupil diameter (trimming volume inner hole) u[{tb  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" iDf,e Kk$'  
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    ' Adjust pupil location to just in front of the lens KoS*0U<g6  
    parID = FindFullName( "Geometry.Arizona Eye" ) bGorH=pb5R  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) Znetzm=0  
    count = 0 %TsPyiYl  
    While GetOperationCount(eID)>count x"~~l  
        GetOperation eID, count, op f nI|  
        If op.Type="ShiftZ" Then {W##^
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            DeleteOperation eID,count +*_5tWAc  
            count=count-1 [V}S<Xp  
        End If /<rt1&0  
        count=count+1 5Vi>%5A>l  
    Wend (!:cen~|[  
    op.Type = "ShiftZ" E#s)52z=B  
    op.val1 = taq-0.01 t-LG }nv  
    op.parent = parID M?;y\vS?.  
    AddOperation eID, op /y>>JxAEb  
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    Print "Set pupil diameter = " & pupilDiam wfjnA~1h  
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    'Update AZ Eye subassembly Description D$JHs4  
    eID = FindFullName( "Geometry.Arizona Eye" ) x
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    GetEntity eID, entity w;l<[q?_  
    entity.Description = "Accommodation = " & A & "D" c*R/]Dn  
    SetEntity eID, entity ^gFqRbuS  
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    Update z.}[m,oTF  
    Print "DONE!" n6k9~"?  
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End Sub *& m#qEv  
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如果屈光度是4，光瞳直径是4，则会输出如下数据： 'KPASfC  
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Accommodation = 4 Diopters {?`al5Sz  
Pupil Diameter = 4 mm 07hF2[i  
Set aqueous humor thickness = 2.81 yZ!T8"mz{  
Set anterior lens radius = 10.4 and conic constant = -2.375869 YX*Qd$chZ  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 n!qV>k9Y  
Set lens thickness = 3.927 j;Z?WXWDh  
Set lens index of refraction = 1.42672 f#Xy
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Set pupil diameter = 4 $k$4% 7  
DONE! 'fL"txW