Arizona眼睛模型

=pQA!u]QE   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+?@4?`z   cRBdIDIc   模型 WvVHSa4{   ZzET8?8   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。 ?r"][<   Table 1. AZ眼睛模型的定义 &kh7|:{j   a-\\A[E   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. ],vUW#6$N   9{bG @g   光源 j&n][=PL   0MDdcjqw   多个光源定义来分析该模型的不同特性。图1显示了所以的光源和提示信息告诉您他们可以用来做什么。 e6n1/TtqM   2*:lFvwP   图1. 光源和提示信息使用 wWs<{ T   1(6B|w5+   除了“Letter F”之外的所有光源的光线位置设定在了孔径光阑位置处，并增加了pre-propagation distance= -8。尽管光线在光瞳处创建，规定的传输方向相对于光线位置在pre-propagation distance之后。这意味着光束沿着Z轴在眼睛的前面以平行光入射，而不是在光瞳处入射。 ??tyz4$;   gAt[kW< n   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。 /rp.H'hC   图2. 字母F光源的设定方法光 c]:sk[u   '^pA%I2D   图3. 字母F在视网膜上位置点列图 WK5~"aw   D6&fDhO27   视网膜的散射 !{5jP |vo   7e$\|~<   在散射文件中，有一个名为“Retina surface”的72%的反射型朗伯散射，它为视网膜的散射提供了一个粗略的近似。为了模拟来自视网膜的散射，改变自定义元件“Eye ball” 下的视网膜的表面从“halt all” 到”Allow All”。并使几何中“plane”可追迹。 fRKO> /OT   z[:UPPbW   图4. 视网膜朗伯散射设定 IgH[xwzy[   Rt!G:hy7   注意在视网膜的表面有散射重点采样规格定义，在“Scatter”标签的底部可获取该信息。“toward pupil”指定散射光朝向光瞳，半角度10度。 lN94 b3_W   q H&7Q{   图5. 视网膜重点采样规格设定 weCRhA   (5[|h   脚本 ])paU8u   Hm2}xnY   内置脚本使用对话框显示屈光度和光瞳直径的数值设置。使用FRED Basic脚本创建和使用对话框非常容易。图6显示了如何获取用户自定义对话框，如下图所示： "5Oi[w&F5   图6. 用户对话框的创建与编辑 Ep-{Ew{T_=   图7. 用户对话框编辑器 Qo+_:N   s6<`#KFAg   如果“OK”按钮按下，将会核对对话框下面的代码行，如果点击取消则脚本终止。然后输入的参数赋予变量，如果此处是保留为空白，则使用默认值。因此，如果没有值输入并点击“OK”按钮，则脚本是以屈光度为0，光瞳直径为4mm来运行的。 "-JJ6Bk   余下的脚本计算与屈光度有关的所有参数。 :_v/a+\n   Isv@V.   分析 xzF@v>2S+   b%>vhj&F   屈光度为4，光瞳直径为4mm，字母F点在视网膜上所成的像。 iyNyj44 H   图7. 字母F在视网膜上颜色分析 <-uE pF   q)R&npP7   脚本代码 lV!ecJw$   b}'XDw    Option Explicit     'Remove this to enable non-dimensioned variables to be used. xXQ#?::m   'T@K$xL8   Dim entity As T_ENTITY < V)T_   Dim op As T_OPERATION 1GB$;0 W),   Dim mat As T_MODELMATERIAL Q`ERI5b6   Dim A As Double 3XY;g{`=q   Dim pupilDiam As Double g+8{{o=   Dim eID As Long hKv3;jcd   Dim parID As Long 4"72   Dim count As Integer `9M:B&   Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double nW2fB8yq   Dim tlens As Double, nlens As Double !`S?   Dim curv As Double, conic As Double g+BW~e)   Dim ok As Long *44^M{ti<   eaP,M kK&   Sub Main @F)51$Ld   %!$ua_8       '用户输入对话框 TNBFb_F       Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 f h05*]r           TextBox 220,21,40,21,.TextBox1 'default: 0 lot7SXvK           Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 *njdqr2c~           OKButton 40,91,90,21 cl4`FU           CancelButton 190,91,90,21 NN1d?cOn           Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 nokk!v/           TextBox 220,49,40,21,.TextBox2 'default: 4 *qKPZb~       End Dialog HHu|X`tc       Dim dlg As UserDialog vgRjd1k.\y   MB|+F       ok = Dialog (dlg) 2ILMf?}   0eq="|n^|       If ok=0 Then    'cancel button was pressed kzPHPERA]           Print "Execution cancelled." s,>_kxuX           End [*zB vj}G       End If A-<\?13uW   v-2_#       'Assign accommodation and pupil diameter & use defaults if field left empty TR3_!0       If dlg.TextBox1 = "" Then +')\,m "z           A = 0           'Default accommodation V9Bi2\s*       Else 2Jo'!|]           A = CDbl(dlg.TextBox1) `.Z MwA       End If VS0 &[bl   KP" lz       If dlg.TextBox2 = "" Then IB#L5yN r           pupilDiam = 4   'Default pupil diameter %rVC3}       Else )s^D}I(           pupilDiam = CDbl(dlg.TextBox2) "O1\]"j       End If [pi!+k   \{       Print " " Dd8*1,       Print "Accommodation = " & A & " Diopters" b:Oa4vBa       Print "Pupil Diameter = " & pupilDiam & " mm" wi/Fx=w   Pe[~kog,TP       ' Calculate new parameters with accommodation $(pzh:|       taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness JK:i-   !4zSE,1       Rant = 12.0 - 0.4*A                     'Radius of anterior lens V'(yrz!       CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens t|q@~B :   71`)@y,Z,       Rpost = -5.224557 + 0.2*A               'Radius of posterior lens jyRSe^x       CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens P)x&9OHV   -Z)j"J       tlens = 3.767 + 0.04*A                  'Lens thickness @R%n &   b*w izd       nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction ~/LO @   Gkci_A*       'Adjust parameters to account for accommodation 0LX;Vvo   i X4?5yz~<       '************************************************************************* Dizc#!IGU       'Aqueous thickness (Position of Lens) ST'M<G%4E       '************************************************************************* %D|p7&       eID = FindFullName( "Geometry.Arizona Eye.Lens" ) e=$p(       GetCustomElement eID, entity tow0/Jt   * S4IMfp       parID = FindFullName( "Geometry.Arizona Eye" ) apsR26\^   h:{rjXK       ' Delete any shift(s) in z pC<~\RR       count = 0 %Wy$m?gD       While GetOperationCount(eID)>count  hUy"XXpr           GetOperation eID, count, op OxGKtnAjf           If op.Type="ShiftZ" Then !DgN@P.o               DeleteOperation eID,count h!l&S2)D`               count=count-1 1& %6sZN           End If akg$vHhK4           count=count+1 u0^Vy#@_       Wend [JI>e;l C:   NN(ZH73       'Set new shift in dO/iL7K&       op.Type = "ShiftZ" ^ Pqj*k+F       op.val1 = taq v%gkQa       op.parent = parID N]gJ(g       AddOperation eID, op MDkcG"O       Print "Set aqueous humor thickness = " & taq-0.55 o@SL0H-6|   hRK&       '************************************************************************* -|s w\Q       'Radius and conic constant of anterior lens @Z9X^Y+u^h       '************************************************************************* B",5"'id       eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) SM%N]/@U       GetConic eID, entity, curv, conic d .wu    r@e/<bz9       SetConic eID, entity, 1/Rant, CCant b EB3#uc       Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant @ol}~&"   _:(RkS!x       '************************************************************************* @)[Q6w `x       'Radius and conic constant of posterior lens }J=>nL'B       '************************************************************************* xi5G?r       eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) Udj !y$?       GetConic eID, entity, curv, conic aU&p7y4C@   +fh@m h0[       SetConic eID, entity, 1/Rpost, CCpost l|WdJn o       Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost i_/ A,5TF   [4p~iGC       '************************************************************************* Y~ku?/"6T       'Lens thickness (Position of posterior lens surface) ]O}TK^%       '************************************************************************* "cJ))v-'   {J#SpG 7       parID = FindFullName( "Geometry.Arizona Eye.Lens" ) T'VZ=l[   Kkfza       ' Delete any z-shift(s) dJvT2s.t[       count = 0 ?w^MnK0U)       While GetOperationCount(eID)>count q<Tx'Ya           GetOperation eID, count, op B{}<DP.           If op.Type="ShiftZ" Then ZLP)i;A z               DeleteOperation eID,count b'x26wT?               count=count-1 QMO.Bnek           End If %5g(|Y]           count=count+1 OKW}8q M       Wend > nHaMj   j p"hbV       'Set new z-shift zx#HyO[a       op.Type = "ShiftZ" *'?aXS -'r       op.val1 = tlens "Zh3,       op.parent = parID <b JF&,       AddOperation eID, op asEk3       Print "Set lens thickness = " & tlens #)3luf3G   ;?{[vLHDL       '************************************************************************* #uRj9|E7       'Lens index of refraction (5rfeSA^       '************************************************************************* \v\f'eQ       eID = FindMaterial( "Lens" ) RpmOg       GetModelMaterial eID, mat e]9Z]a2   {l0[`"EF       mat.Nd = nlens 8]@$7hy8       SetModelMaterial eID, mat 3Q0g4#eP       Print "Set lens index of refraction = " & nlens 5>Kk>[|.   Lg%3M8-W~       '************************************************************************* Q9G\T:^ury       'Pupil diameter -v@LJCK7I       '************************************************************************* s(.H"_a       eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) {s7 3(B"   " ""k}M2A       'Adjust pupil diameter (trimming volume inner hole) mz>GbImVD~   o=]\Jy       SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" 5^5hhm4   m;4qs#qCg?       ' Adjust pupil location to just in front of the lens E4QLXx6Wa&       parID = FindFullName( "Geometry.Arizona Eye" ) aPToP.e       eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) W9D~:>^YP       count = 0 6 l,8ev       While GetOperationCount(eID)>count 5+DId7d'n           GetOperation eID, count, op 6*&$ha}X           If op.Type="ShiftZ" Then saa3BuV 6               DeleteOperation eID,count PDgd'y               count=count-1 `R!%k]$           End If "@^^niSFl           count=count+1 "Snt~:W>       Wend 31GqWN`>$       op.Type = "ShiftZ" ^TZ`1:oL#       op.val1 = taq-0.01 *|4/XHi       op.parent = parID vojXo|c       AddOperation eID, op 91#rP|88;   #E$*PAB       Print "Set pupil diameter = " & pupilDiam VPr`[XPXb   oQiRjDLx       'Update AZ Eye subassembly Description }?)U`zF)7}       eID = FindFullName( "Geometry.Arizona Eye" ) kNd(KQ<.17       GetEntity eID, entity L$z(&%Nx       entity.Description = "Accommodation = " & A & "D" /(u# D[       SetEntity eID, entity "wR1=&gk   QOR92}yC       Update z -c1,GOD       Print "DONE!" Qv WvS9]        B,fVNpqo   End Sub ipe8U1Sc   `iNH`:[w   如果屈光度是4，光瞳直径是4，则会输出如下数据： 5X73@Aj   A2.GNk   Accommodation = 4 Diopters .TM. v5B   Pupil Diameter = 4 mm -A,UqEt   Set aqueous humor thickness = 2.81 oZ_, WwnE   Set anterior lens radius = 10.4 and conic constant = -2.375869 az1#:Go   Set posterior lens radius = -4.424557 and conic constant = -3.081019 P''>wjMH0   Set lens thickness = 3.927 dczq,evp   Set lens index of refraction = 1.42672 z"c,TlVN3   Set pupil diameter = 4 RT. %\)))   DONE!

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