Arizona眼睛模型

{4G/HW28   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"q|   1^}I?PbqV   模型 LnI   $ItjVc@U   模型的定义如表1种所示，由半径、圆锥常数、折射率、阿贝数、到下一面的距离等一系列表面组成。一些参数由屈光度（A）来决定。 Ww2@!ng   Table 1. AZ眼睛模型的定义 Z_\p8@3aH   9{toPED   在FRED中使用0屈光度来创建的，光瞳加在了透镜的前面。材料是创建一个新的材料并选择类型“Model Material”,输入的参数是nd和vd. Q5+1'mzAB   YX0ysE*V:&   光源 5I622d   { qNPhi   多个光源定义来分析该模型的不同特性。图1显示了所以的光源和提示信息告诉您他们可以用来做什么。 P=QxfX0B   2*|T)OA`m,   图1. 光源和提示信息使用 a#YK1n[!   Hc)z:x;Sj   除了“Letter F”之外的所有光源的光线位置设定在了孔径光阑位置处，并增加了pre-propagation distance= -8。尽管光线在光瞳处创建，规定的传输方向相对于光线位置在pre-propagation distance之后。这意味着光束沿着Z轴在眼睛的前面以平行光入射，而不是在光瞳处入射。 ky2 bj}"p9   lK0ny>RB   在往下看是内置的脚本用来修改屈光度，使其为4（250mm），光源“Letter F”在视网膜处生成一个字母为F的图像。绿色的光线聚焦的非常好而红色和蓝色光线有一点的模糊。使用Positions Spot Diagram分析工具来观察最为合适。 Lgg ,K//g   图2. 字母F光源的设定方法光 _QPqF{iI   ZSC*{dD$E   图3. 字母F在视网膜上位置点列图 P8tdT3*6/   54+(o6E<   视网膜的散射 BzzC|   VfX^iG r   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。 4 <y   mlnF,+s   图4. 视网膜朗伯散射设定 3 jZMXEG)   >HP `B2Q H   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。 s,HbW%s   95l)s],   图5. 视网膜重点采样规格设定 u^" I3u8$   EuK}L[Kl   脚本 ~KBa-i%o   ;CYoc4e   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： #De>EQ%   图6. 用户对话框的创建与编辑 G;Li!H   图7. 用户对话框编辑器 zBF~:Uc`B   p['RV   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。 l4bytI{63   余下的脚本计算与屈光度有关的所有参数。 36"n7   xE/?ncTK^   分析 e97G]XLR   |N.2iN:   屈光度为4，光瞳直径为4mm，字母F点在视网膜上所成的像。 7oE0;'   图7. 字母F在视网膜上颜色分析 O=B=0   )PX VR T   脚本代码 C8U3+ s   `Ij@;=(   Option Explicit     'Remove this to enable non-dimensioned variables to be used. ma.84~m   "4N&T#   Dim entity As T_ENTITY 1EyN |m|   Dim op As T_OPERATION }Q\%tZC#T   Dim mat As T_MODELMATERIAL &@0~]\,D7   Dim A As Double "r9Rr_, >   Dim pupilDiam As Double 82r8K|L.<y   Dim eID As Long a3@E`Z   Dim parID As Long Q Be6\oq   Dim count As Integer qE[S>/R"   Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double Ds9)e&yYrb   Dim tlens As Double, nlens As Double K d&/9<{>   Dim curv As Double, conic As Double +jm,nM9   Dim ok As Long 0dchOUj   Y|>dS8f;4   Sub Main l/.{F;3F   bZqTT~'T       '用户输入对话框 ij"~]I       Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 a=z] tTs4           TextBox 220,21,40,21,.TextBox1 'default: 0 e;]tO-Nu           Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 ['d9sEv.           OKButton 40,91,90,21 E/;t6&6           CancelButton 190,91,90,21 Hfcpqa           Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 Pfd1[~,           TextBox 220,49,40,21,.TextBox2 'default: 4 | xO*!NR       End Dialog g'"~'       Dim dlg As UserDialog >!963>DR   E&M(QX5       ok = Dialog (dlg) d$t"Vp   Fr9/TI       If ok=0 Then    'cancel button was pressed 70'OS:J=\           Print "Execution cancelled." ~ao:9ynY           End $y(;"hy       End If PX:#+bq1   djd/QA fSC       'Assign accommodation and pupil diameter & use defaults if field left empty 6u[fCGi%       If dlg.TextBox1 = "" Then ]C_+u_9           A = 0           'Default accommodation !/FRL<mp       Else #:K=zV\           A = CDbl(dlg.TextBox1) kDmm       End If I /E9:   7J'%;sH       If dlg.TextBox2 = "" Then 0vY_           pupilDiam = 4   'Default pupil diameter p3s i\Fm!       Else I^NDJdxd           pupilDiam = CDbl(dlg.TextBox2) I"Oq< _       End If 2t= =<x   c=m'I>A       Print " "  RD$:.       Print "Accommodation = " & A & " Diopters" 'eM0i[E+`       Print "Pupil Diameter = " & pupilDiam & " mm" r!:yUPv   "{q#)N       ' Calculate new parameters with accommodation c=!>m       taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness w~lH2U'k}   7;>|9k       Rant = 12.0 - 0.4*A                     'Radius of anterior lens 4G&`&fff]       CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens S?~0)EXj(   >eJ<-3L;       Rpost = -5.224557 + 0.2*A               'Radius of posterior lens 5.rAxdP       CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens I G1];vX   ,H=k5WA4m       tlens = 3.767 + 0.04*A                  'Lens thickness N' hT    ;ALWL~Xm       nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction MAh1tYs4D   (x=$b(I       'Adjust parameters to account for accommodation Q}BMvR 9w   ImXYI7PL       '************************************************************************* b8WtNVd       'Aqueous thickness (Position of Lens) 1@]&i Z]       '************************************************************************* dNACE*g;q       eID = FindFullName( "Geometry.Arizona Eye.Lens" ) uwwR$ (\7       GetCustomElement eID, entity YxF@1_g   (r|m&/       parID = FindFullName( "Geometry.Arizona Eye" ) T#!>mL|9|   t G_4>-Y#w       ' Delete any shift(s) in z t"=5MaQk-       count = 0 wZvv5:jKpu       While GetOperationCount(eID)>count Wjb_H (D           GetOperation eID, count, op b3A0o*           If op.Type="ShiftZ" Then 35\ |#2qw6               DeleteOperation eID,count $1f2'_`8~               count=count-1 p-4$)w~6i           End If K%q5:9m           count=count+1 '*J+mZtN       Wend Gwd38   qb>ULP0       'Set new shift in (< +A w7       op.Type = "ShiftZ" 4@9Pd &I       op.val1 = taq {npm9w<;       op.parent = parID e]4$H.dP       AddOperation eID, op bzr2Zj{4       Print "Set aqueous humor thickness = " & taq-0.55 oE ' P   VLuHuih       '************************************************************************* t2[/eM.G       'Radius and conic constant of anterior lens ^exU]5nvz       '************************************************************************* uw;Sfx,s       eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) 4H{t6t@-:       GetConic eID, entity, curv, conic C;W@OS-;   s6H.Q$3L       SetConic eID, entity, 1/Rant, CCant wQ33Gc       Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant g=Z52y`N<   EBy7wU`S       '************************************************************************* Ht[$s40P       'Radius and conic constant of posterior lens )vW'g3u_       '************************************************************************* V}y]<       eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) Qs1p       GetConic eID, entity, curv, conic |A&;m}(Mt   P$EiD+5#z       SetConic eID, entity, 1/Rpost, CCpost  ?eS;Yc       Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost b-u@?G|<   JduO^Fit       '************************************************************************* 9c@M(U@Yh       'Lens thickness (Position of posterior lens surface) E)-;sFz       '************************************************************************* .S//T/3O]Q   JL M Xkcc       parID = FindFullName( "Geometry.Arizona Eye.Lens" ) ~F"S]   -1Q24jrO-       ' Delete any z-shift(s) <h -)zI       count = 0 UoxlEec       While GetOperationCount(eID)>count [F6)Z[uG           GetOperation eID, count, op {4g';           If op.Type="ShiftZ" Then 8~Kq"wrbu               DeleteOperation eID,count 2uj .*               count=count-1 <K CI@           End If KA2>[x2           count=count+1 '+9<[]       Wend 9pLe8D   r#z cl)rbU       'Set new z-shift UT;%I_i!'       op.Type = "ShiftZ" ;\K]~       op.val1 = tlens t3)6R(JC       op.parent = parID FX!KX/OE)       AddOperation eID, op 6 byeO&d       Print "Set lens thickness = " & tlens h*Fv~j'p   2 7)IfE       '************************************************************************* S~/2Bw!2       'Lens index of refraction ,U""m7        '************************************************************************* =Kj{wA O       eID = FindMaterial( "Lens" ) gX"-3w       GetModelMaterial eID, mat )+N{D=YM   3Q,&D'];[       mat.Nd = nlens '8 .JnCg       SetModelMaterial eID, mat T=PqA)Ym       Print "Set lens index of refraction = " & nlens wO]e%BTO   }ny7LQ       '************************************************************************* 4X^$"lM       'Pupil diameter OlT8pG5Oa       '************************************************************************* ]Thke 4       eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) ny KfM5s_   vn}m-U XA*       'Adjust pupil diameter (trimming volume inner hole) 8:0/Cj   8\s#law       SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" }u ma<b   I8XP`Ccq       ' Adjust pupil location to just in front of the lens  E0!d c       parID = FindFullName( "Geometry.Arizona Eye" ) e]VW\6J&       eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) ,sitOy}ks       count = 0 ==Egy:<:Q       While GetOperationCount(eID)>count G2|jS@L#           GetOperation eID, count, op {py%-W           If op.Type="ShiftZ" Then B@*b 9               DeleteOperation eID,count ]W;6gmV               count=count-1 YrnC'o`           End If q8P&rMwy           count=count+1 Erw1y,mF       Wend UOb`@ #       op.Type = "ShiftZ" #G#gc`S-,       op.val1 = taq-0.01 8&U Mmbgy       op.parent = parID ?z>J7 }w*=       AddOperation eID, op d.?}>jl   NK qIx       Print "Set pupil diameter = " & pupilDiam x3i}IC   =mXC,<]       'Update AZ Eye subassembly Description 4'z)J1M       eID = FindFullName( "Geometry.Arizona Eye" ) u\Cf@}5(       GetEntity eID, entity - VJx)g       entity.Description = "Accommodation = " & A & "D" 3O,nNt;L{       SetEntity eID, entity {wC*61@1   opH!sa@U       Update @eJ8wf]       Print "DONE!" ?9t4>xKn        ;qaPK2a8   End Sub @<P2di   H^|TV]^;N   如果屈光度是4，光瞳直径是4，则会输出如下数据：  igo9~.   4Kch=jt4#   Accommodation = 4 Diopters <\O+   Pupil Diameter = 4 mm SOI=~BGd)   Set aqueous humor thickness = 2.81 Bf*>q*%B{   Set anterior lens radius = 10.4 and conic constant = -2.375869 Fq~uuQ   Set posterior lens radius = -4.424557 and conic constant = -3.081019 {.2\}7.c   Set lens thickness = 3.927 0g[ %)C   Set lens index of refraction = 1.42672 IW~wO   Set pupil diameter = 4 Jw _>I   DONE!

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