Arizona眼睛模型

a4=(z72xe   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。 X3X_=qzc   ]MosiMJF   模型 Jt@lH   @2)nhW/z6   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。 2_+>a"8Y   Table 1. AZ眼睛模型的定义 5;UIz@BJ   J5I@*f)l   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. -` U|5   x9 %=d   光源 e12QYoh   Q>Zc eJ;   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。 =I@t%Y   oDz|%N2s|   图1. 光源和提示信息使用 ,0.kg   f7lj,GAZ   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。 ?<TJ}("/   Aj4 a-vd.   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。 E,}{iqAb   图2. 字母F光源的设定方法光 _9 ]:0bDUo   |JxVfX8^   图3. 字母F在视网膜上位置点列图 )hXTgUZa   Wye* ~t   视网膜的散射 Cp6S2v I   <$0is:]   在散射文件中，有一个名为“Retina surface”的72%的反射型朗伯散射，它为视网膜的散射提供了一个粗略的近似。为了模拟来自视网膜的散射，改变自定义元件“Eye ball” 下的视网膜的表面从“halt all” 到”Allow All”。并使几何中“plane”可追迹。 |Ev|A9J!   % /VCjuV   图4. 视网膜朗伯散射设定 '|[V}K5m/f   , ~O>8VbF   注意在视网膜的表面有散射重点采样规格定义，在“Scatter”标签的底部可获取该信息。“toward pupil”指定散射光朝向光瞳，半角度10度。 ;7QXs39S   ZH_$Q$9   图5. 视网膜重点采样规格设定 Z~~6y6p   G?1GkR   脚本 j|k/&q[St   W2 -%/   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： oAQQ OtpZN   图6. 用户对话框的创建与编辑 P1Hab2%+   图7. 用户对话框编辑器 Q&eyqk    g<W]NYm   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。 olE(#}7V   余下的脚本计算与屈光度有关的所有参数。 7__[=)(b2X   4,I,f>V   分析 )S g6B;CJ   CUu Owx6%   屈光度为4，光瞳直径为4mm，字母F点在视网膜上所成的像。 hv|a8=U!R   图7. 字母F在视网膜上颜色分析 b>;?{   FvpU]   脚本代码 @:C)^f"   /?'~`4!(   Option Explicit     'Remove this to enable non-dimensioned variables to be used. eU1F7LS   ]F4QZV ( M   Dim entity As T_ENTITY nK1eh@a9Qv   Dim op As T_OPERATION TTz=*t+D   Dim mat As T_MODELMATERIAL ShI1f   Dim A As Double tYu<(Z(l)   Dim pupilDiam As Double k$3pmy*   Dim eID As Long Kjd3!%4mB   Dim parID As Long x77L"5 g   Dim count As Integer !kovrvM6F   Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double >G6kF!V   Dim tlens As Double, nlens As Double wk|+[Rl;L   Dim curv As Double, conic As Double J:@gmo`M;V   Dim ok As Long ^wIB;!W   <fvu) f   Sub Main 4z0gyCAC A   "cKD#       '用户输入对话框 \f9WpAY       Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 FS1\`#Bm)           TextBox 220,21,40,21,.TextBox1 'default: 0 v`A)GnNiN           Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 7;EDU           OKButton 40,91,90,21 (U:-z=E#1           CancelButton 190,91,90,21 }dkXRce*           Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 q<&1,^A           TextBox 220,49,40,21,.TextBox2 'default: 4 u cpU$+       End Dialog J!uG/Us       Dim dlg As UserDialog d&+]@ Ii   \l GD8@,x       ok = Dialog (dlg) f24W*#IX   >+M[!;m}       If ok=0 Then    'cancel button was pressed 1K Fd ~U           Print "Execution cancelled." xMjhC;i{           End Ib..X&N2       End If A9xeOy8e   c4fH/-       'Assign accommodation and pupil diameter & use defaults if field left empty qp})4XTv       If dlg.TextBox1 = "" Then \CjJa(vV           A = 0           'Default accommodation v"k ?e       Else pP| @Z{7d`           A = CDbl(dlg.TextBox1) R-Edht|{       End If w6vbYPCN   iB)\*)       If dlg.TextBox2 = "" Then *tqD:hiF           pupilDiam = 4   'Default pupil diameter rCPIz<       Else qO>UN[Y           pupilDiam = CDbl(dlg.TextBox2) wn[)/*(,$(       End If :nIMZRJ_!E   05wkUo:9       Print " " a=MN:s?Fc0       Print "Accommodation = " & A & " Diopters" KhR3$|fH<       Print "Pupil Diameter = " & pupilDiam & " mm" vb>F)X?b_   w/#7G\U       ' Calculate new parameters with accommodation F$t]JM       taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness )g@+ MR   ED` 1)1<       Rant = 12.0 - 0.4*A                     'Radius of anterior lens f;'*((       CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens 5M5Bm[X   ~5P9^`KNH       Rpost = -5.224557 + 0.2*A               'Radius of posterior lens z*},N$2=       CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens ~@'wqGTp   yj:@Fg-3g       tlens = 3.767 + 0.04*A                  'Lens thickness $Tbsre\MJ   u> {aF{       nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction KU8,8:yY   kkl'D!z2g       'Adjust parameters to account for accommodation &wQ;J)13   yQhO-jT       '************************************************************************* rUKg<]&@       'Aqueous thickness (Position of Lens) |+Wn5iT       '************************************************************************* HYdM1s6vo       eID = FindFullName( "Geometry.Arizona Eye.Lens" ) V(` ]hH0;T       GetCustomElement eID, entity l#[Z$+!09   ys`-QlkB       parID = FindFullName( "Geometry.Arizona Eye" ) XUP{]w`.Z   }c8nn       ' Delete any shift(s) in z m"!SyN}&9?       count = 0 $@ Vn+| Ix       While GetOperationCount(eID)>count V|YQhd0kv           GetOperation eID, count, op R'gd/.[e           If op.Type="ShiftZ" Then EDnNS               DeleteOperation eID,count Au2?f~#Fv               count=count-1 5UQ{qm*Q           End If mu\1hKq;B           count=count+1 Z1fY' f       Wend V*n$$-5 1-   X.<3/       'Set new shift in ~xqiasE#K       op.Type = "ShiftZ" T";evM66       op.val1 = taq /si<Fp)z       op.parent = parID B?BOAH       AddOperation eID, op s*rR >D:       Print "Set aqueous humor thickness = " & taq-0.55 3jZGO9ttnS   jRg/N_2'2       '************************************************************************* 6k hBT'n       'Radius and conic constant of anterior lens ]T)N{"&N/       '************************************************************************* y,:WLk~       eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) LuySa2,       GetConic eID, entity, curv, conic =dQ[I6   $W7}Igx#       SetConic eID, entity, 1/Rant, CCant 0`E G-Hw       Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant _*H Hdd5I   ChK-L6       '************************************************************************* LAC&W;pJ"       'Radius and conic constant of posterior lens eWFkUjz       '************************************************************************* ,yC.. aI       eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) xn`)I>v       GetConic eID, entity, curv, conic n$2oM5<   o-bH3Jkb]&       SetConic eID, entity, 1/Rpost, CCpost O7 ;=g!j       Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost NFTv4$5d   @aQ:3/       '************************************************************************* Q\4tzb]       'Lens thickness (Position of posterior lens surface) K9zr]7;th       '************************************************************************* zr!7*, p   8-@@QZ\N       parID = FindFullName( "Geometry.Arizona Eye.Lens" ) X$UK;O   U,!qNi}       ' Delete any z-shift(s) )p>Cf_[.       count = 0  0J+WCm `       While GetOperationCount(eID)>count CcUF)$kz           GetOperation eID, count, op kn}^oRT           If op.Type="ShiftZ" Then %%K3J<5               DeleteOperation eID,count zg ,=A?               count=count-1 *IOrv)           End If MiZ<v/L2           count=count+1 6CFnE7TQf       Wend _".h(   X{x(p       'Set new z-shift 8=$XhC       op.Type = "ShiftZ" Z7bJ<TpZ       op.val1 = tlens n{N0S^h       op.parent = parID sgOau\E       AddOperation eID, op T'}kCnp       Print "Set lens thickness = " & tlens ~R[ k^i.Y   Y$>NsgQn6       '************************************************************************* x_~_/&X5       'Lens index of refraction IM1&g7Qs2       '************************************************************************* $,K@xq5       eID = FindMaterial( "Lens" ) (eF[nfM       GetModelMaterial eID, mat )Lz =[e   qh.F}9o       mat.Nd = nlens f_)#       SetModelMaterial eID, mat by+xK~>       Print "Set lens index of refraction = " & nlens *f 7rLM*   w<H2#d>5!@       '************************************************************************* sg=G<50i       'Pupil diameter |yz[mP*;o       '************************************************************************* [;{xiW4V]       eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) ftpPrtaP   pfZ[Y C-       'Adjust pupil diameter (trimming volume inner hole) kxKb}>=   *` mxv0w~(       SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" NxF:s,a6   >TglX t+       ' Adjust pupil location to just in front of the lens .u\$wJ9Ai       parID = FindFullName( "Geometry.Arizona Eye" ) k6"(\d9o       eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) LCSvw       count = 0 ]*P9=!x|M       While GetOperationCount(eID)>count vLxaZWr           GetOperation eID, count, op hdWVvN           If op.Type="ShiftZ" Then ]2l}[ w71|               DeleteOperation eID,count l7uTk5               count=count-1 Tv1oy%dK           End If gs!' *U)           count=count+1 i#4+l$q       Wend T%oJmp?0       op.Type = "ShiftZ" +%j27~R>D       op.val1 = taq-0.01 AmC9qk8Q       op.parent = parID `Kg!aN       AddOperation eID, op ~S<aIk0l   9<0yz?b':       Print "Set pupil diameter = " & pupilDiam }'tJc $!   k={1zl ;       'Update AZ Eye subassembly Description ]&H"EHC<$       eID = FindFullName( "Geometry.Arizona Eye" ) Z $INmo6       GetEntity eID, entity #w%-IhP       entity.Description = "Accommodation = " & A & "D" KDb j C'3       SetEntity eID, entity hBRi5&%   E`.hM}h       Update tl /i       Print "DONE!" OvQzMXU^I        Uhr2"Nuuy   End Sub [K,P)V>K   @5wc 3y   如果屈光度是4，光瞳直径是4，则会输出如下数据： kJl^,q    ?\8   Accommodation = 4 Diopters ,\iXZ5"R   Pupil Diameter = 4 mm UUDHknm"   Set aqueous humor thickness = 2.81 C{$iuus0   Set anterior lens radius = 10.4 and conic constant = -2.375869 K"VcPDK   Set posterior lens radius = -4.424557 and conic constant = -3.081019 } r(b:}DN   Set lens thickness = 3.927 6)0.q|Q   Set lens index of refraction = 1.42672 c_ncx|dUs   Set pupil diameter = 4 d)V8FX,t   DONE!

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