Arizona眼睛模型

lu8*+.V   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。 Q'qX`K+@`   Xdwpn+7s   模型 i4]oE& G   On54! m   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。 @mmnr?_w   Table 1. AZ眼睛模型的定义 xK_oV+   $ nHD,h   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. 'y=N_/+s   tJ 2GSZ`   光源 u`&lTJgF/O   >,E^ R`y   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。 ]Axz}:   b\"w /'XX   图1. 光源和提示信息使用 zgH(/@P   ;1s+1G}_z   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。 bK.*v4RG   fvcS=nR Qv   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。 0{g*\W*+~   图2. 字母F光源的设定方法光 Bp3E)l   _CfJKp)   图3. 字母F在视网膜上位置点列图 Xjkg7p,HD@   XbqMWQN*   视网膜的散射 j:xC\b47"   [:FiA?O]   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。 o8Gygi5   R(`:~@3\6   图4. 视网膜朗伯散射设定 ^lAM /    }f]Y^>-Ux   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。 ,zltNbu\.(   |K"Q>V2y   图5. 视网膜重点采样规格设定 u8]FJQ*\6+   ]"lB!O~   脚本 m1U:&{:^   fT|A^   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： W*t] d   图6. 用户对话框的创建与编辑 >WIc"y.   图7. 用户对话框编辑器 Dlq!:dF{&   n{FjFlX2=   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。 PO`p.("h   余下的脚本计算与屈光度有关的所有参数。 aPVzOBp   -cM1]so T   分析 p,goYF??   iN[x *A|h   屈光度为4，光瞳直径为4mm，字母F点在视网膜上所成的像。 B*,) @h   图7. 字母F在视网膜上颜色分析 \gk.[={^P    C/IF~<B   脚本代码 ,VHqZ'6   1|(Q|   Option Explicit     'Remove this to enable non-dimensioned variables to be used. =c'4rJ$+   $2Whb!7Z(   Dim entity As T_ENTITY 6e%@uB}$   Dim op As T_OPERATION >%k6k1CZ   Dim mat As T_MODELMATERIAL RqtBz3v   Dim A As Double I I+y   Dim pupilDiam As Double r<uc HRO#   Dim eID As Long bI55G#1G   Dim parID As Long A~2)ZdAN   Dim count As Integer 4b`E/L}2   Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double gvA}s/    Dim tlens As Double, nlens As Double e@Lxduq   Dim curv As Double, conic As Double 5e/YEDP   Dim ok As Long @kW L "yy,   }l|S]m!   Sub Main x9"Cm;H%   ->8Kd1^F       '用户输入对话框 l1)~WqhE}       Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 u^~7[OkE           TextBox 220,21,40,21,.TextBox1 'default: 0 _&uJE&xl}           Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 At'CT5=           OKButton 40,91,90,21 m&:&z7^p           CancelButton 190,91,90,21 L"qJZU           Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 x b"z%. j           TextBox 220,49,40,21,.TextBox2 'default: 4 9 {&g.+       End Dialog BDB*>y7(       Dim dlg As UserDialog Dfs*~H63   7k(}U_v       ok = Dialog (dlg) Vr1}Zv3K'   2.D2 o       If ok=0 Then    'cancel button was pressed 0%ul6LvM           Print "Execution cancelled." EtKq.<SJ           End n#lbfN 4       End If X0G,tl   +e>SK!kB7       'Assign accommodation and pupil diameter & use defaults if field left empty m/KaWrw/)       If dlg.TextBox1 = "" Then 2:*15RH3           A = 0           'Default accommodation Mu \V3`j       Else ?woL17Gt           A = CDbl(dlg.TextBox1) S&_03       End If Vu:ZG*^   CS7b3p!I       If dlg.TextBox2 = "" Then *;fTiL           pupilDiam = 4   'Default pupil diameter sbW+vc       Else r#sg5aS7O|           pupilDiam = CDbl(dlg.TextBox2) ^kKLi       End If Qr.{_M   79T_9}M       Print " " JQV%W+-@       Print "Accommodation = " & A & " Diopters" qyz%9 9       Print "Pupil Diameter = " & pupilDiam & " mm" |+Y-i4t   A{+/$7vek       ' Calculate new parameters with accommodation sL$sj|"S       taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness hX.cdt_?   uY]';OtG       Rant = 12.0 - 0.4*A                     'Radius of anterior lens \p4*Q}t       CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens *k{Llq   OrkcY39"~a       Rpost = -5.224557 + 0.2*A               'Radius of posterior lens WLUgiW(0$       CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens SZWNN#w60?   ^E70$yB^       tlens = 3.767 + 0.04*A                  'Lens thickness yKML{N1D   {7:1F)Pj       nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction e>MtDJ5   JHxcHh       'Adjust parameters to account for accommodation TGJz[Ny   q,P.)\0A       '************************************************************************* +^AdD8U       'Aqueous thickness (Position of Lens) K*@?BE       '************************************************************************* A;co1,]gR       eID = FindFullName( "Geometry.Arizona Eye.Lens" ) iJ{axa &       GetCustomElement eID, entity $DDO9   ,RPb<3 B       parID = FindFullName( "Geometry.Arizona Eye" ) v}DNeIh~   NS[Z@@       ' Delete any shift(s) in z 1uo-?k       count = 0 O60T.MM`       While GetOperationCount(eID)>count JI@iT6.%IX           GetOperation eID, count, op AROHe           If op.Type="ShiftZ" Then MV5$e               DeleteOperation eID,count {QEvc               count=count-1 !zK"y[V           End If a!o%x           count=count+1 (#dR\Di       Wend \#[DZOI~   z(A60b}       'Set new shift in 3Dr\ O_`u       op.Type = "ShiftZ" 27Gff(       op.val1 = taq zTue(Kr       op.parent = parID Y~Uf2(7b5       AddOperation eID, op |E6Thvl$       Print "Set aqueous humor thickness = " & taq-0.55 Y$OE[nGi%X   %g?M?D8Ud3       '************************************************************************* X!hzpg(`hR       'Radius and conic constant of anterior lens R(}<W$(TV       '************************************************************************* `@y~ JNf!       eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) nzbVI       GetConic eID, entity, curv, conic DlzL(p@r    K-'uE)       SetConic eID, entity, 1/Rant, CCant >_Tyzl>z       Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant |K.I%B   !~zn*Hm       '************************************************************************* %|4Kak]:Q       'Radius and conic constant of posterior lens %0&,_jM/9       '************************************************************************* O}C*weU       eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) ;-JF1p7;       GetConic eID, entity, curv, conic U9B htmY   TTO8tT3[6}       SetConic eID, entity, 1/Rpost, CCpost -medD G       Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost /\,3AInLb   2?qT,pN       '************************************************************************* <mJ8~       'Lens thickness (Position of posterior lens surface) z$QoMq]       '************************************************************************* 8A0a/ 7Lj   P:Q&lnC       parID = FindFullName( "Geometry.Arizona Eye.Lens" ) }se3y   w!`e!}       ' Delete any z-shift(s) 3B]E2       count = 0 ByE@4+9       While GetOperationCount(eID)>count ,OrrGwp&           GetOperation eID, count, op LmY[{.'tX           If op.Type="ShiftZ" Then bRggt6$z               DeleteOperation eID,count (0@b4}Z               count=count-1 W2`3PEa           End If E;H9]*x/           count=count+1 U `lp56       Wend 3K||(   P\@kqf~pC       'Set new z-shift zv"NbN       op.Type = "ShiftZ" {.U:Ce       op.val1 = tlens UOj*Gt &       op.parent = parID aQHR=.S]X       AddOperation eID, op "kFNOyj3\       Print "Set lens thickness = " & tlens M:.+^.h   ~p'|A}9[/       '************************************************************************* l_;6xkv4       'Lens index of refraction u[SqZftmO       '************************************************************************* ;wJe%Nw?       eID = FindMaterial( "Lens" ) e2fv%       GetModelMaterial eID, mat |7KWa(V5I   3 [#Rm>,Vu       mat.Nd = nlens /j3",N+I       SetModelMaterial eID, mat J(8?6&=ck       Print "Set lens index of refraction = " & nlens gKQs:25   P B-x_D       '************************************************************************* CL`+\ .       'Pupil diameter W8x&:5Fc)3       '************************************************************************* n2_;:=       eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) /V cbT >=   ?v:FGO       'Adjust pupil diameter (trimming volume inner hole) }l}_'FmQ   O46v       SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" ;,uATd|   {2Ew^Li       ' Adjust pupil location to just in front of the lens [jCYj0Qf8       parID = FindFullName( "Geometry.Arizona Eye" ) _B^X3EOc       eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) ,o0Kevz       count = 0 0t(c84o5       While GetOperationCount(eID)>count unqUs08           GetOperation eID, count, op /oJ &\pI           If op.Type="ShiftZ" Then ~K5A$s2               DeleteOperation eID,count 3mopTzs)               count=count-1 @+~>utr           End If bLGC           count=count+1 wKpb%3       Wend /kw;q{>?o       op.Type = "ShiftZ" 2yFT` 5+H4       op.val1 = taq-0.01 Yv)c\hm(7j       op.parent = parID uzmYkBv       AddOperation eID, op f.%3G+   Zl'/Mxg       Print "Set pupil diameter = " & pupilDiam _cC!rq U1   Tb;,t=;u       'Update AZ Eye subassembly Description (GGosXU-v       eID = FindFullName( "Geometry.Arizona Eye" ) gMZ+kP`       GetEntity eID, entity \ q q       entity.Description = "Accommodation = " & A & "D" =j~:u.hc'       SetEntity eID, entity ;; {K##^l   QBi]gT@&g       Update Z'uiU e`&       Print "DONE!" /:{4,aX2        IsJx5GO   End Sub ?WqaT)l~   ;!=i|"PG   如果屈光度是4，光瞳直径是4，则会输出如下数据： Ahba1\,N$   ,~1sZ`C   Accommodation = 4 Diopters oP4+:r)LKD   Pupil Diameter = 4 mm |N)),/R_   Set aqueous humor thickness = 2.81 Og@{6>   Set anterior lens radius = 10.4 and conic constant = -2.375869 E`@Z9k1 `   Set posterior lens radius = -4.424557 and conic constant = -3.081019 |'P$zMAF   Set lens thickness = 3.927 .}Xf<G&   Set lens index of refraction = 1.42672 ]auqf   Set pupil diameter = 4 qP&:9eL   DONE!

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