Arizona眼睛模型

&GXtdO>;Zv   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。 :@:g*w2K   |RHO+J   模型 [WcS[](ob   UlK/x"JDv   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。 jG+ T.   Table 1. AZ眼睛模型的定义 &FL%H;Kfx   G[|3^O>P   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. 8pXfT%]   umJay />   光源 1k!D0f3qb   GYFgEg}   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。 Nawp t%   ! a86iHU   图1. 光源和提示信息使用 \ua9thO G   <$"7~i/X   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。 b2a'KczV   }=Hf?';m   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。 qv.[k<~a>   图2. 字母F光源的设定方法光 2;&mkcK'   c}YJqhk0J   图3. 字母F在视网膜上位置点列图 V%i<;C   TAXd,z N   视网膜的散射 60~v t04   V78Mq:7d   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。 2}D,df'W4   w+Ad$4Pf "   图4. 视网膜朗伯散射设定 ^%-NPo<   cL6 6gOEL   注意在视网膜的表面有散射重点采样规格定义，在“Scatter”标签的底部可获取该信息。“toward pupil”指定散射光朝向光瞳，半角度10度。 i:g{{Uuv   ?( ]a*~rx   图5. 视网膜重点采样规格设定 C#Y,r)l   D[V`^CTu   脚本 ym HKcQ   <inl{CX/   内置脚本使用对话框显示屈光度和光瞳直径的数值设置。使用FRED Basic脚本创建和使用对话框非常容易。图6显示了如何获取用户自定义对话框，如下图所示： LOe4c0C6Ca   图6. 用户对话框的创建与编辑 :RPVT,O}   图7. 用户对话框编辑器 P~&O4['<   Gj6<s./   如果“OK”按钮按下，将会核对对话框下面的代码行，如果点击取消则脚本终止。然后输入的参数赋予变量，如果此处是保留为空白，则使用默认值。因此，如果没有值输入并点击“OK”按钮，则脚本是以屈光度为0，光瞳直径为4mm来运行的。 SO7(K5H,   余下的脚本计算与屈光度有关的所有参数。 x]H3Y3   yxqTm%?y   分析 ,&0Z]*   Xu6 jHJ@x   屈光度为4，光瞳直径为4mm，字母F点在视网膜上所成的像。 K/DH / r   图7. 字母F在视网膜上颜色分析 :g&>D#{   fQxSMPWB   脚本代码 M\I_{Q?_   2ed@HJu   Option Explicit     'Remove this to enable non-dimensioned variables to be used. |n)<4%i8J   /({P1ti:C   Dim entity As T_ENTITY #uB[&GG}W   Dim op As T_OPERATION R;%^j=Q   Dim mat As T_MODELMATERIAL 5qGGu.$Ihi   Dim A As Double =<Hy"4+?.   Dim pupilDiam As Double 8`a,D5U:   Dim eID As Long *JwFD^<j   Dim parID As Long 6F,/w:   Dim count As Integer !`Le`c   Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double r;9z5'   Dim tlens As Double, nlens As Double f7.m=lbe   Dim curv As Double, conic As Double Ohc^d"[7   Dim ok As Long :r\xkHg/f   2,+d|1(4o   Sub Main R!9qQn?   h5j<u       '用户输入对话框 UBa-       Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 ci;&CHa           TextBox 220,21,40,21,.TextBox1 'default: 0 _n7%df           Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 A^8x1ydZ           OKButton 40,91,90,21 -gB{:UYi3           CancelButton 190,91,90,21 f0OgK<.>T           Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 HXyFj           TextBox 220,49,40,21,.TextBox2 'default: 4 1}`2\3,       End Dialog Q~8y4=|#CY       Dim dlg As UserDialog QOd!]*W`?m   v3~FR,Kl       ok = Dialog (dlg) W|0My0y    K,6OGsh       If ok=0 Then    'cancel button was pressed  Ll?g.z"           Print "Execution cancelled." @bE~@4mOu           End $ND90my       End If b1H7   gXF.on4B       'Assign accommodation and pupil diameter & use defaults if field left empty 9] Lo       If dlg.TextBox1 = "" Then ERp{gB2U?           A = 0           'Default accommodation K0LbZMn,/       Else i]dz}=j'           A = CDbl(dlg.TextBox1) ;|;iCaD a+       End If {-J:4*`   Wy8,<K{       If dlg.TextBox2 = "" Then 4Mi~1iZj           pupilDiam = 4   'Default pupil diameter zx7#)*       Else oikxg!0S           pupilDiam = CDbl(dlg.TextBox2) q1jN]H       End If v"/TmiZ   /e .D/;]       Print " " V\"1wV~E       Print "Accommodation = " & A & " Diopters" RvR:e|       Print "Pupil Diameter = " & pupilDiam & " mm" i2`#    -IbbPuRq       ' Calculate new parameters with accommodation *<UGgnmLE       taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness Y|:YrZSC   UTvs |[       Rant = 12.0 - 0.4*A                     'Radius of anterior lens xb]odYGdW       CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens rtus`A5p   z|Ap\[GS       Rpost = -5.224557 + 0.2*A               'Radius of posterior lens \ @8*TS       CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens 4QO/ff[ o   k8 u%$G       tlens = 3.767 + 0.04*A                  'Lens thickness t{6ap+%L   e$ 32       nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction W"|mpxp   LJj=]_       'Adjust parameters to account for accommodation +v!v[qn   4T%cTH:.9N       '************************************************************************* obj!I7       'Aqueous thickness (Position of Lens) aiJnfU]W       '************************************************************************* 2uEhOi0I       eID = FindFullName( "Geometry.Arizona Eye.Lens" ) >(OYK}ZN       GetCustomElement eID, entity \q,s?`+B   i%MA"I\9       parID = FindFullName( "Geometry.Arizona Eye" ) -,|ha>r   g}m+f]|       ' Delete any shift(s) in z d@Q][7       count = 0 7OE[RX8!f       While GetOperationCount(eID)>count M7vj^mt?           GetOperation eID, count, op HitAc8           If op.Type="ShiftZ" Then rw]yKH               DeleteOperation eID,count #)`\!)?               count=count-1 u1N1n;#           End If P.h.MA]           count=count+1 5j`v`[B;       Wend @/ k x er   p1~*;;F       'Set new shift in sl^n6N       op.Type = "ShiftZ" =zOeb/       op.val1 = taq Dkw*Je#6PX       op.parent = parID .jargvAL*       AddOperation eID, op AEqq1A       Print "Set aqueous humor thickness = " & taq-0.55 :!']p2B   F"[3c6yF       '************************************************************************* as#J qE       'Radius and conic constant of anterior lens p-Pz=Cx-       '************************************************************************* >C# kqxfg       eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) ]-a{IWVN       GetConic eID, entity, curv, conic oq. r\r   q#'VJA:A5&       SetConic eID, entity, 1/Rant, CCant 9n 6fXOC       Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant # 66e@   HCazwX       '************************************************************************* )!sa)\E?       'Radius and conic constant of posterior lens ;cLUnsB\       '************************************************************************* ]F+K|X9-       eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) puF%=i       GetConic eID, entity, curv, conic f ?maa5S   gz4UV/qr/       SetConic eID, entity, 1/Rpost, CCpost r[!(?%>j       Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost ?:/|d\,7@   @)b^^Fp       '************************************************************************* {R8=}Qo       'Lens thickness (Position of posterior lens surface) s!de2z       '************************************************************************* UJn/s;$.e   5(#-)rlGj       parID = FindFullName( "Geometry.Arizona Eye.Lens" ) Q;w B{vr$    eT-9       ' Delete any z-shift(s) vYdlSe=6G       count = 0 pX_b6%yX(       While GetOperationCount(eID)>count c{4R*|^           GetOperation eID, count, op 3\+N`!           If op.Type="ShiftZ" Then jI0]LD1k               DeleteOperation eID,count @ae >b               count=count-1 Ow)R|/e/           End If tN2 W8d           count=count+1 (3W&AM       Wend +NR n0 z(   ?bI?GvSh       'Set new z-shift mp:m`sh*i       op.Type = "ShiftZ" l#xw.2bo       op.val1 = tlens h'!V8'}O?       op.parent = parID ]! )xr       AddOperation eID, op SH=:p^J       Print "Set lens thickness = " & tlens u E.^w;~2=   (}jL_E       '************************************************************************* %w:'!X><       'Lens index of refraction }"4roJ       '************************************************************************* 6#|qg*OS       eID = FindMaterial( "Lens" ) rJV?)=Z       GetModelMaterial eID, mat vi|Zit   !FP"M+       mat.Nd = nlens u>o<tw%Y       SetModelMaterial eID, mat a.,i.2       Print "Set lens index of refraction = " & nlens 1Is%]6   c[:Wf<%|       '************************************************************************* oyW00]ka       'Pupil diameter u`6/I#q`       '************************************************************************* xYwkFB$$*       eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) ?gG, t4D   q,@+^aZ       'Adjust pupil diameter (trimming volume inner hole) H&K3"Ulw   l&|)O6N       SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" MS{{R+&   :o$@F- $k       ' Adjust pupil location to just in front of the lens WIG=D{\Yx       parID = FindFullName( "Geometry.Arizona Eye" ) ,R~eY?{a       eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) Mz\yP T;Y       count = 0 Q!]IG;3Sx|       While GetOperationCount(eID)>count 1i+FL''           GetOperation eID, count, op )S Q('vwg           If op.Type="ShiftZ" Then pYh!]0n               DeleteOperation eID,count <r;o6>+               count=count-1 PkJcd->           End If +6376$dC           count=count+1 4=s9A       Wend SSQ T;>       op.Type = "ShiftZ" ZqP7@fO_%       op.val1 = taq-0.01 <m1sSghg       op.parent = parID w+Vk3c5uI)       AddOperation eID, op Rf:<-C0T   !7c'<[+Hm       Print "Set pupil diameter = " & pupilDiam Fx5ZwT t   Z(UD9wY5m       'Update AZ Eye subassembly Description A$<>JVv       eID = FindFullName( "Geometry.Arizona Eye" ) lR}%)3_k       GetEntity eID, entity Mciq-c)       entity.Description = "Accommodation = " & A & "D" gIBpOPr^d       SetEntity eID, entity |Ng"C`$oqv   T<M?PlED       Update H/`G       Print "DONE!" !;+U_j'Pg        P}l#VJWp   End Sub `#U ]iwW!   HL8(lP gS   如果屈光度是4，光瞳直径是4，则会输出如下数据： 0\wiam-   3KT_AJ4}   Accommodation = 4 Diopters LfllO   Pupil Diameter = 4 mm gLx/w\l6   Set aqueous humor thickness = 2.81 QPV@'.2m   Set anterior lens radius = 10.4 and conic constant = -2.375869 \gd6Yx^[   Set posterior lens radius = -4.424557 and conic constant = -3.081019 jE*Ff&]%m   Set lens thickness = 3.927 pw;r 25    Set lens index of refraction = 1.42672 */Cj$KY70   Set pupil diameter = 4 OM{Dq|   DONE!

)Oe`s(O@[I

VWD.J