Arizona眼睛模型

D<[kbt5^7   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。 Ol;"}3*Z*   I~-sBMm(w   模型 gU?M/i2   gGs"i]c   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。 MI`<U:-lP   Table 1. AZ眼睛模型的定义 $4]4G=o   i\* b<V   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. j3[kG#   HLqDI lL   光源 p1IN%*IV+o   |WgFLF~k   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。 $`L |   Seq ^o=   图1. 光源和提示信息使用 `*B6T7p1   Io('kCOR;   除了“Letter F”之外的所有光源的光线位置设定在了孔径光阑位置处，并增加了pre-propagation distance= -8。尽管光线在光瞳处创建，规定的传输方向相对于光线位置在pre-propagation distance之后。这意味着光束沿着Z轴在眼睛的前面以平行光入射，而不是在光瞳处入射。 41+@!`z7   0Q]{r )   在往下看是内置的脚本用来修改屈光度，使其为4（250mm），光源“Letter F”在视网膜处生成一个字母为F的图像。绿色的光线聚焦的非常好而红色和蓝色光线有一点的模糊。使用Positions Spot Diagram分析工具来观察最为合适。 .la_u8A]   图2. 字母F光源的设定方法光 .RbPO#(   |"}rC >+   图3. 字母F在视网膜上位置点列图 ]zI*}(adu   }'uV{$   视网膜的散射 V}h)e3X   k:&B b"   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。 ) gxN'z   :S+Bu*OyH   图4. 视网膜朗伯散射设定 NH'Q MjL)   >ffQ264g=i   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。 ^+Vf*YY 8   iq5-eJmq   图5. 视网膜重点采样规格设定 S AKIFNE   DyRU$U   脚本 %~N| RSec   NHhKEx0Gtu   内置脚本使用对话框显示屈光度和光瞳直径的数值设置。使用FRED Basic脚本创建和使用对话框非常容易。图6显示了如何获取用户自定义对话框，如下图所示： `L3{y/U'   图6. 用户对话框的创建与编辑 5+/XO>P1m|   图7. 用户对话框编辑器 0 R>!jw   6Zv-kG   如果“OK”按钮按下，将会核对对话框下面的代码行，如果点击取消则脚本终止。然后输入的参数赋予变量，如果此处是保留为空白，则使用默认值。因此，如果没有值输入并点击“OK”按钮，则脚本是以屈光度为0，光瞳直径为4mm来运行的。 Yb'% J@T}   余下的脚本计算与屈光度有关的所有参数。 |gfG\fL3V   =r~ExW}+   分析 &E-q(3-   M[0NB2`Wp   屈光度为4，光瞳直径为4mm，字母F点在视网膜上所成的像。 2 >xEE   图7. 字母F在视网膜上颜色分析 cfHtUv   +y 48.5   脚本代码 QPB^%8   -LlS9[r0   Option Explicit     'Remove this to enable non-dimensioned variables to be used. f ~f)6XU|   AzSmfEaU0   Dim entity As T_ENTITY ?p>m;Aq   Dim op As T_OPERATION c(s: f@ 1   Dim mat As T_MODELMATERIAL H9[0-Ur5   Dim A As Double zo1fUsK?   Dim pupilDiam As Double 2 yRUw   Dim eID As Long VD+v\X_   Dim parID As Long  >Xxi2Vy   Dim count As Integer IJLuu@kRm,   Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double -CTLQyj)   Dim tlens As Double, nlens As Double (:RYd6i   Dim curv As Double, conic As Double c+ aTO"   Dim ok As Long b\UE+\a&   kXOc)   Sub Main 9{-H/YS\_s   R'^J#"[       '用户输入对话框 -.5R.~@       Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 @CKMJ^#|           TextBox 220,21,40,21,.TextBox1 'default: 0 g2YE^EKU~           Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 ,9$|"e&           OKButton 40,91,90,21 /'bX}H(dq           CancelButton 190,91,90,21 l(8@?t^;           Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 *EFuK8 ;           TextBox 220,49,40,21,.TextBox2 'default: 4 Y"TrF(C       End Dialog }eSrJgF4M       Dim dlg As UserDialog jEL"Q?#   x}OJ~Yk]       ok = Dialog (dlg) JHJ]BMm   q<cxmo0 S       If ok=0 Then    'cancel button was pressed !#PA#Q|cO           Print "Execution cancelled." UTO$L|K           End .lGN Fx       End If jM>;l6l   E*L5D4Kw       'Assign accommodation and pupil diameter & use defaults if field left empty i4)]lWnd       If dlg.TextBox1 = "" Then $]4o!Z           A = 0           'Default accommodation RP9~n)h~b       Else ?v&2^d4C*F           A = CDbl(dlg.TextBox1) ">q?(i\       End If UryHte   lN*"?%< x>       If dlg.TextBox2 = "" Then .+5;AtN           pupilDiam = 4   'Default pupil diameter {]O.?Yru?       Else 3o#K8EL           pupilDiam = CDbl(dlg.TextBox2) Y0ACJ?|       End If SOluTFxUw   ceae~       Print " " &Zo+F]3d       Print "Accommodation = " & A & " Diopters" P8 R^46       Print "Pupil Diameter = " & pupilDiam & " mm" ozl>Au   g+-^6UG       ' Calculate new parameters with accommodation '^tC|)       taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness Ib"fHLWA^!   U}GO* +       Rant = 12.0 - 0.4*A                     'Radius of anterior lens )O>M~       CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens va!fJ   vQ>8>V       Rpost = -5.224557 + 0.2*A               'Radius of posterior lens B8>@q!G8P       CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens fBKN?]BdN   /pJr%}sc       tlens = 3.767 + 0.04*A                  'Lens thickness }*7Gq   WPPDvB       nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction jm[f|4\   Pxgal4{6       'Adjust parameters to account for accommodation 0<nW nD,z   c& "1Z/tR       '************************************************************************* g ~%IA.$c       'Aqueous thickness (Position of Lens) WmE4TL^8?       '************************************************************************* H^g&e$d0       eID = FindFullName( "Geometry.Arizona Eye.Lens" ) uIR        GetCustomElement eID, entity ix 5\Y   |pE ~       parID = FindFullName( "Geometry.Arizona Eye" ) @Suww@<   W2A!BaH%       ' Delete any shift(s) in z \psO$TxF=       count = 0 9-y<= )       While GetOperationCount(eID)>count H`7T;`Yb           GetOperation eID, count, op J$&2GAi           If op.Type="ShiftZ" Then ^%qQ)>I=j               DeleteOperation eID,count }p*WH$!~               count=count-1 I<S*"[nV           End If 1(jx.W3           count=count+1 `-5gsJ       Wend #2%8@?_-M   KD'}9{F,       'Set new shift in 3H%bbFy       op.Type = "ShiftZ" _+ >V(,{G       op.val1 = taq ;>Z0e`=       op.parent = parID ZsGJ[       AddOperation eID, op ;z~j%L%b       Print "Set aqueous humor thickness = " & taq-0.55 ~2QD.(   #YSFiy:+r_       '************************************************************************* r`PD}6\       'Radius and conic constant of anterior lens kM3#[#6$!       '************************************************************************* YyC$\HH6       eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) $Eo-58<q       GetConic eID, entity, curv, conic m2Wi "X(I_   A9LVS&52       SetConic eID, entity, 1/Rant, CCant ^C;ULUn3       Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant H~W =#Cx   H2CpZK'       '************************************************************************* KqXPxp^_Al       'Radius and conic constant of posterior lens Oo9'       '************************************************************************* ex|h&Vma2V       eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) ne=C N!=       GetConic eID, entity, curv, conic O?iLLfs   c>wne\(5H       SetConic eID, entity, 1/Rpost, CCpost [vxHsY3z       Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost a!,X@5   \Z-Fu=8J8^       '************************************************************************* 2W;2._       'Lens thickness (Position of posterior lens surface) 1}OM"V       '************************************************************************* B9]bv]   P3TM5       parID = FindFullName( "Geometry.Arizona Eye.Lens" ) 6Z{(.'Be   RT[E$H       ' Delete any z-shift(s) ZN!<!"~       count = 0 !'a <Dw5       While GetOperationCount(eID)>count LB^xdMXi           GetOperation eID, count, op U"L-1]L           If op.Type="ShiftZ" Then Bx|h)e9               DeleteOperation eID,count mnU8i=v0A               count=count-1 0*6Q8`I           End If +_ny{i`'           count=count+1 cpphnGj5       Wend 8*&YQId~   Kr+#)S       'Set new z-shift YAd%d|Q       op.Type = "ShiftZ" n39EKH rm%       op.val1 = tlens 5JS*6|IbD{       op.parent = parID ."ytBF       AddOperation eID, op CM) V^k*       Print "Set lens thickness = " & tlens l$m}aQ%h   S]Aaf-X_       '************************************************************************* 40 zO4       'Lens index of refraction 0KjCM4t       '************************************************************************* rv2;)3/*       eID = FindMaterial( "Lens" ) imyfki $B       GetModelMaterial eID, mat \og2\Oh&gH   8qoA5fW>       mat.Nd = nlens 877Kv);       SetModelMaterial eID, mat *TPWLR ^       Print "Set lens index of refraction = " & nlens T[2<_nn=   kv<(N       '************************************************************************* A|yU'k       'Pupil diameter m,ur{B8 :       '************************************************************************* o+Q2lO5       eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) IaO*{1re   6#HnA"I2n       'Adjust pupil diameter (trimming volume inner hole) Yh{5O3(;   M*aYcIU((       SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" SZvC4lOn#   kkXe=f%       ' Adjust pupil location to just in front of the lens m",G;VN       parID = FindFullName( "Geometry.Arizona Eye" ) Ho $+[K       eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) nD}<zj$D2       count = 0 t;_1/mt       While GetOperationCount(eID)>count 3A\Z]L           GetOperation eID, count, op 3V<c4'O\W           If op.Type="ShiftZ" Then h;~NA}>               DeleteOperation eID,count D[{"]=-               count=count-1 A>\3FeU>UC           End If Bk5ft4v-           count=count+1 upFe{M@       Wend vgi`.hk       op.Type = "ShiftZ" 1yTw*vH F       op.val1 = taq-0.01 m3XT8F*&       op.parent = parID /bmkt@$-0       AddOperation eID, op S(0JBGC   ^}lL@Bd|       Print "Set pupil diameter = " & pupilDiam z2q!_ ~   Hio+k^       'Update AZ Eye subassembly Description boZ /*+t       eID = FindFullName( "Geometry.Arizona Eye" ) #;UoZJ B       GetEntity eID, entity FA;B:O@:'       entity.Description = "Accommodation = " & A & "D" C#RueDa.       SetEntity eID, entity ER:K^ Za   'Y]<1M>.g       Update v+CW([zAx#       Print "DONE!" milQxSpj        ){w!<Lb   End Sub y8]vl;88yY   R9UC0D:-x   如果屈光度是4，光瞳直径是4，则会输出如下数据： ^[v>B@p*{   0\+$j5;   Accommodation = 4 Diopters ^tVIPH.R   Pupil Diameter = 4 mm `R*!GHro   Set aqueous humor thickness = 2.81 4}]In/yA   Set anterior lens radius = 10.4 and conic constant = -2.375869 !ED,'d%J   Set posterior lens radius = -4.424557 and conic constant = -3.081019 <f0yh"?6VH   Set lens thickness = 3.927 :^]FpUY   Set lens index of refraction = 1.42672 M->#WGl\B   Set pupil diameter = 4 VYrs4IFT$   DONE!

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