Arizona眼睛模型

5e8-?w%e   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。 acZ|H   (y4Eq*n%!   模型 4i&!V9@:   CMjPp`rA   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。 Y tj>U   Table 1. AZ眼睛模型的定义 "Ksd9,J\b   54_m{&hb   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. |Q q'_4:   W] 7?;#Hpk   光源 xT(.#9   )tg*dE   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。 F+-MafN7Y   uHh2>Px   图1. 光源和提示信息使用 8(K~QvE~   >Nqkz?67   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。 ATewdq[C   a'fb0fz   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。 w8Vzx8   图2. 字母F光源的设定方法光 mM~Q!`Nf.   ?&^l8gE   图3. 字母F在视网膜上位置点列图 RaqrVC   5S?Xl|8E   视网膜的散射 B|w}z1.   "d*   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。 Ase1R=0   [vJosbU;   图4. 视网膜朗伯散射设定 .S FwjriZ   8u23@ ?   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。 JsdEA   imuHSxcaV   图5. 视网膜重点采样规格设定 cW>`Z:6{K   SK2pOZN   脚本 p{u}t!`!d   7P(:!ce4-   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： #jR?C9&!(   图6. 用户对话框的创建与编辑 ld0WZj   图7. 用户对话框编辑器 c9K\K~bk   UcIR0BYa   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。 v0pEN\   余下的脚本计算与屈光度有关的所有参数。 E$baQU hKS   7k3\_BHyb\   分析 ^B]t4N2i   7] H4E.(l   屈光度为4，光瞳直径为4mm，字母F点在视网膜上所成的像。 L>*|T[~   图7. 字母F在视网膜上颜色分析 3*L ,48wX   lTNkmQ   脚本代码 Cr"hu;   ? -tw*2+   Option Explicit     'Remove this to enable non-dimensioned variables to be used. WocFID:b   E_#&L({|@   Dim entity As T_ENTITY ]z$<6+G   Dim op As T_OPERATION 6 >2! kM7   Dim mat As T_MODELMATERIAL x6]?}Q>>D   Dim A As Double Z%{2/mQ   Dim pupilDiam As Double =!2   Dim eID As Long B.b)YE '   Dim parID As Long Y"U&3e,   Dim count As Integer n+w>Qz'   Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double r,\(Y@I   Dim tlens As Double, nlens As Double 8;@eY`0(   Dim curv As Double, conic As Double C8-q<t#SF   Dim ok As Long 0J B"@U&-   ^8*.r+7p   Sub Main _;+&'=6.[   :2+:(^l       '用户输入对话框 3H2'HO       Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 l,3tU|V           TextBox 220,21,40,21,.TextBox1 'default: 0 hHQt4 r'd           Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 C.Yz<?;S           OKButton 40,91,90,21 k3w#^ "i           CancelButton 190,91,90,21 0Oq1ay^            Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 xC]/i(+bA           TextBox 220,49,40,21,.TextBox2 'default: 4 auU{Iy        End Dialog nfEk,(:       Dim dlg As UserDialog s4\2lBU?   bL<cgtz7)       ok = Dialog (dlg) 9lwg`UWl,   :nn'>       If ok=0 Then    'cancel button was pressed *&km5@*           Print "Execution cancelled." <U";V)           End Ex{]<6UAu       End If #';r 0?|   *%.*vPJ       'Assign accommodation and pupil diameter & use defaults if field left empty _;9)^})$       If dlg.TextBox1 = "" Then z'o+3zq^           A = 0           'Default accommodation qIl@,8T       Else |b'AWI81D           A = CDbl(dlg.TextBox1) g|Cnj       End If &+p07   `CBTZG09       If dlg.TextBox2 = "" Then =6 hf'lP           pupilDiam = 4   'Default pupil diameter Yi3DoaS;"       Else 5;+Bl@zGu           pupilDiam = CDbl(dlg.TextBox2) Qoc-ZC"<6       End If }_S]!AWz   x1Uj4*Au       Print " " (<t)5?@%       Print "Accommodation = " & A & " Diopters" 5 X rn]       Print "Pupil Diameter = " & pupilDiam & " mm" G!uxpZ    )DW;Gc       ' Calculate new parameters with accommodation Mh\c+1MFs       taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness B7 T+a   E;SFf       Rant = 12.0 - 0.4*A                     'Radius of anterior lens eL*Edl|#       CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens V_:/#G]jeG   vKxwv YDe       Rpost = -5.224557 + 0.2*A               'Radius of posterior lens RN;Tqq):       CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens -c. a7   v "07H       tlens = 3.767 + 0.04*A                  'Lens thickness #gP\q?5Ov   y_w4ei       nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction 'k hJ Z:   8V@3T/}       'Adjust parameters to account for accommodation UCFef,VW   Cs<d\"+       '************************************************************************* LY7'wONx       'Aqueous thickness (Position of Lens) j`bOJTBE       '************************************************************************* FRr<K^M       eID = FindFullName( "Geometry.Arizona Eye.Lens" ) <D?`*#K       GetCustomElement eID, entity Y,{Xv   4IVCTz[       parID = FindFullName( "Geometry.Arizona Eye" ) Q[ IaA"   9 HuE'(wQ       ' Delete any shift(s) in z h c"n?       count = 0 )7f:hg       While GetOperationCount(eID)>count tkA '_dcIC           GetOperation eID, count, op -LF^u;s8&S           If op.Type="ShiftZ" Then 0I,-1o|s               DeleteOperation eID,count {ES3nCL(8               count=count-1 zKR_P{W>^           End If Pp?J5HW           count=count+1 :Q89j4,       Wend 5 gE   TB9ukLG^<<       'Set new shift in V`G]4}       op.Type = "ShiftZ" PR6{Y]e%       op.val1 = taq 75a3H`       op.parent = parID N=(rl#<       AddOperation eID, op ]krOPM/       Print "Set aqueous humor thickness = " & taq-0.55 EBJaFz'   .Sm7na K       '************************************************************************* `.@N9+Aj       'Radius and conic constant of anterior lens 9R!.U\sq       '************************************************************************* 3ILEc:< 0J       eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) mZmwCS8       GetConic eID, entity, curv, conic dx|j,1e   I~Ziq10       SetConic eID, entity, 1/Rant, CCant }I!D65-#'       Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant z.FO6y6L   ) g)X~]*       '************************************************************************* rTQrlQ:@       'Radius and conic constant of posterior lens vU::dr       '************************************************************************* (2X`imJ       eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) %Z Z\Xj       GetConic eID, entity, curv, conic \qKh9   !fY'^Ya?       SetConic eID, entity, 1/Rpost, CCpost 0} uH       Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost #49,7OBU   f$R]m2       '************************************************************************* M1^pf<!s       'Lens thickness (Position of posterior lens surface) YajUdpJi       '************************************************************************* ? 3T d>x   d(<[$3.       parID = FindFullName( "Geometry.Arizona Eye.Lens" ) [+UF]m%W   Ft'?43J       ' Delete any z-shift(s) Y}QtgZEt       count = 0 =5is T       While GetOperationCount(eID)>count ;BsyN[bF           GetOperation eID, count, op xwq {0jY           If op.Type="ShiftZ" Then +9M#-:qB               DeleteOperation eID,count rz5AIe>Hm               count=count-1 \G:\36l           End If N"Q-xK           count=count+1 !{jDZ?z{h       Wend C0J/FFBQ^   @uApm~}       'Set new z-shift @-)jU!       op.Type = "ShiftZ" U,\3 !D0jt       op.val1 = tlens I'm.+(1m,       op.parent = parID 3U^E<H       AddOperation eID, op bkTk:-L5:       Print "Set lens thickness = " & tlens Z$"E|nRN   Dn1aaN6       '************************************************************************* Jsde+G,N       'Lens index of refraction 8tJB/Pw`S       '************************************************************************* %v5IR       eID = FindMaterial( "Lens" ) 7S|nn|\Kp       GetModelMaterial eID, mat yL{X}:;}   (Rj'd>%c       mat.Nd = nlens yy8h8{=g       SetModelMaterial eID, mat P :zZ       Print "Set lens index of refraction = " & nlens [z =KHk   >UlAae44       '************************************************************************* 5FKb7       'Pupil diameter TL'^@Y7X5       '************************************************************************* Z7)la |       eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) =MMU(0 E   |L wn<y       'Adjust pupil diameter (trimming volume inner hole) M<$a OW0   _[M*o0[@W       SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" cHP~J%&L   gqw ]L>Z       ' Adjust pupil location to just in front of the lens B*B}eXUph       parID = FindFullName( "Geometry.Arizona Eye" ) Vh=10Et       eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) {{N*/E^       count = 0 _!_%A fz       While GetOperationCount(eID)>count  vf}.)           GetOperation eID, count, op 4TX~]tEyky           If op.Type="ShiftZ" Then {5`=){               DeleteOperation eID,count L{&5Ets               count=count-1 ,0k3Qi%           End If PLoD^3uG)           count=count+1 f i#p('8       Wend A43 mX!g\       op.Type = "ShiftZ" |&wwH&<[z       op.val1 = taq-0.01 V[#eeH)/       op.parent = parID uP h/u!       AddOperation eID, op % XvJJ   KF!?;q0J       Print "Set pupil diameter = " & pupilDiam ):<9j"Z;At   r" 4u)H>       'Update AZ Eye subassembly Description }:SWgPfc       eID = FindFullName( "Geometry.Arizona Eye" ) ,]FcWx \u       GetEntity eID, entity V d`}F0WD       entity.Description = "Accommodation = " & A & "D" h=*eOxR"4^       SetEntity eID, entity cI#! Y   'j&+Pg)@       Update 1>)q5D       Print "DONE!" k z{_H`5.        D^dos`L0b   End Sub (?y (0%q   Fx!NRY_   如果屈光度是4，光瞳直径是4，则会输出如下数据： X7."hGu@   $*-U Y   Accommodation = 4 Diopters &GKtD)   Pupil Diameter = 4 mm n=_jmR1   Set aqueous humor thickness = 2.81 yUY* l@v]   Set anterior lens radius = 10.4 and conic constant = -2.375869 CQ;.}=j ,   Set posterior lens radius = -4.424557 and conic constant = -3.081019 x b6X8:   Set lens thickness = 3.927 HEBKRpt   Set lens index of refraction = 1.42672 @a~GHG[x   Set pupil diameter = 4 P[q 'Y^\   DONE!

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