Arizona眼睛模型

9Q/!%y%5   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。 Hrnql   \[EWxu   模型 n #I}!x>2   JrTBe73.]j   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。 l)s+"C#   Table 1. AZ眼睛模型的定义 5I,X#}K[   {;DZ@2|   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. /nFw   A5ID I<a   光源 jt--w"|-r   %Qz`SO8x?   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。 EIQy?ig86   Zr;=p"cXr   图1. 光源和提示信息使用 i%8&g2   66^t[[   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。 s.)w A`&&   nk 9 K\I   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。 )\Q|}JV   图2. 字母F光源的设定方法光 {{%8|+B   |7x^@i9w   图3. 字母F在视网膜上位置点列图 j]O[I^5   #%" TU,[+   视网膜的散射 EsB'nf r   d<? :Q   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。 -yGm^EwP   {WOfT6y+   图4. 视网膜朗伯散射设定  89=JC[c   K0=E4>z,`q   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。 wLe&y4   e*6` dz@   图5. 视网膜重点采样规格设定 (kyo?3   C*e[CP@u   脚本 t>@3 RBEK   Y'0?<_ fj   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： x>"JWD   图6. 用户对话框的创建与编辑 3|r!*+.   图7. 用户对话框编辑器 4$GRCq5N;   [<a%\:c m4   如果“OK”按钮按下，将会核对对话框下面的代码行，如果点击取消则脚本终止。然后输入的参数赋予变量，如果此处是保留为空白，则使用默认值。因此，如果没有值输入并点击“OK”按钮，则脚本是以屈光度为0，光瞳直径为4mm来运行的。 @b\_696.   余下的脚本计算与屈光度有关的所有参数。 E(+wl   N:jiZ)   分析 .r%|RWs6W   <?Izfl6   屈光度为4，光瞳直径为4mm，字母F点在视网膜上所成的像。 .x?zky^   图7. 字母F在视网膜上颜色分析 T KL(97)<   {59VS Nl   脚本代码 :42;c:85   U]EuDNkO{   Option Explicit     'Remove this to enable non-dimensioned variables to be used. `4$Qv'X*   8yz((?LrDh   Dim entity As T_ENTITY <O)X89dFM   Dim op As T_OPERATION 1\{U<Oli   Dim mat As T_MODELMATERIAL MGyB8(   Dim A As Double vek:/'sj3p   Dim pupilDiam As Double YGV#.   Dim eID As Long xp8f   Dim parID As Long f%[ ukMj&   Dim count As Integer n9fA!Wic   Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double b<V./rWIB   Dim tlens As Double, nlens As Double 9.OwH(Ax7   Dim curv As Double, conic As Double z/&a\`DsU   Dim ok As Long c1AG3Nb   ,3--ERf   Sub Main \ jXN*A   ;(0$~O$3u       '用户输入对话框 7O9hn2?e       Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 #iU8hUbo           TextBox 220,21,40,21,.TextBox1 'default: 0 _u|FJTk           Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 "~2#!bK7           OKButton 40,91,90,21 P^<0d'(           CancelButton 190,91,90,21 :8-gm"awL5           Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 >g"M.gW           TextBox 220,49,40,21,.TextBox2 'default: 4 ck _fEF       End Dialog ZWhmO=b!       Dim dlg As UserDialog $#ju?B~   J1Ki2I=       ok = Dialog (dlg) ~& WN)r'4y   i@R$g~~-D       If ok=0 Then    'cancel button was pressed dGD^op,6g           Print "Execution cancelled." ]baaOD$Z           End i Kk"j       End If ~z _](HKoS   O][Nl^dl       'Assign accommodation and pupil diameter & use defaults if field left empty 3AQ>>)T~       If dlg.TextBox1 = "" Then V>jhGf           A = 0           'Default accommodation _X2EBpZp       Else %::deV7           A = CDbl(dlg.TextBox1) ' uf\.F       End If 1.95 ^8   =i^<a7M~       If dlg.TextBox2 = "" Then e_~fJ           pupilDiam = 4   'Default pupil diameter ^?7dOW       Else M|({ 4C           pupilDiam = CDbl(dlg.TextBox2) <k\H`P        End If uJam $ V   hUT^V(       Print " " sLAuR       Print "Accommodation = " & A & " Diopters" $S=~YzO       Print "Pupil Diameter = " & pupilDiam & " mm" l/png:   0oj{e9h       ' Calculate new parameters with accommodation +fd@K       taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness <ql w+RVt   pgd8`$(Q       Rant = 12.0 - 0.4*A                     'Radius of anterior lens qQxA@kdd       CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens JYg% ~tW'   EwD3d0udL       Rpost = -5.224557 + 0.2*A               'Radius of posterior lens WfDX"rA       CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens (\T0n [   v"~Do+*+       tlens = 3.767 + 0.04*A                  'Lens thickness [l':G]   z{@R.'BD       nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction )v52y8G-p   hH1lgc       'Adjust parameters to account for accommodation 6mu<&m@   UIf ZPf=       '************************************************************************* Z6^QB@moj       'Aqueous thickness (Position of Lens)  gmRT1T       '************************************************************************* sp=OT-Pfp       eID = FindFullName( "Geometry.Arizona Eye.Lens" ) AUxM)H       GetCustomElement eID, entity ] dHB}   UK6xkra?#       parID = FindFullName( "Geometry.Arizona Eye" ) ^}o7*   &@% b?~       ' Delete any shift(s) in z _^ q\ XPS       count = 0 #`La|a.-       While GetOperationCount(eID)>count ?L@@;tt           GetOperation eID, count, op Pknc[h},           If op.Type="ShiftZ" Then 3$c(M99r               DeleteOperation eID,count @n7t?9Bx               count=count-1 izPh1YA           End If hI |/>4<           count=count+1 g5[D&       Wend 6P~aW   4L5o\'X       'Set new shift in $T?*0"Mj[       op.Type = "ShiftZ" q]6_ rY.       op.val1 = taq X*sr       op.parent = parID iW|s|1mh3       AddOperation eID, op PMgQxM*h       Print "Set aqueous humor thickness = " & taq-0.55 =n-z;/NL   Q !9HA[Ly       '************************************************************************* JFM"ii{8       'Radius and conic constant of anterior lens 9<|m4       '************************************************************************* @iU%`=ziz       eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) _+twqi       GetConic eID, entity, curv, conic ~->Hlxze'K   PSTu/^       SetConic eID, entity, 1/Rant, CCant d/XlV]#2x\       Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant ~ww?Emrw   ^ <qrM       '************************************************************************* ! FNf>z+       'Radius and conic constant of posterior lens GS\%mPZ       '************************************************************************* 'nRp}s1^[       eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) `gBD_0<T7       GetConic eID, entity, curv, conic ;rd6ko   F`!TV(,bY       SetConic eID, entity, 1/Rpost, CCpost F:%^&%\       Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost )YuRjBcp,"   AG]WO8f)       '************************************************************************* u]HS(B,ht       'Lens thickness (Position of posterior lens surface) T yU&QXb       '************************************************************************* 2~f6~\4GL+   NB EpM       parID = FindFullName( "Geometry.Arizona Eye.Lens" ) c~P)4(udT   Nd`HB=ShJ       ' Delete any z-shift(s) _N98vf0o       count = 0 hwiKOP       While GetOperationCount(eID)>count I(pb-oY3!I           GetOperation eID, count, op D7)(D4S4           If op.Type="ShiftZ" Then Qi_&aU$>lM               DeleteOperation eID,count Bg-VCJI<               count=count-1 9"~9hOEct           End If W.^Ei\w/t           count=count+1 Vo%Yf9C       Wend )S^z+3p   e1Ob!N-       'Set new z-shift o]A XT 8       op.Type = "ShiftZ" Nz~(+pVWg5       op.val1 = tlens [*Q-nZ/L       op.parent = parID Rho5s@N7       AddOperation eID, op hp*<x4%*a"       Print "Set lens thickness = " & tlens ?cJY B)   NS@{~;#R       '************************************************************************* MEEAQd<*       'Lens index of refraction <P1rqM9^       '************************************************************************* UR}kB&t       eID = FindMaterial( "Lens" ) R2l[Q){!       GetModelMaterial eID, mat 4IZlUJ?j+c   AM'gnP>       mat.Nd = nlens (^LS']ybc       SetModelMaterial eID, mat i3\~Qj;1       Print "Set lens index of refraction = " & nlens r@iASITX   x=.tiM{#       '************************************************************************* 8W;2oQN7       'Pupil diameter %swR: B v       '************************************************************************* e&0N K8&#+       eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) V$(/0mQV(   ZRnL_z~       'Adjust pupil diameter (trimming volume inner hole) G Mb(10T`   6UlF5pom       SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" e2c1pgs&+   tjj^O%SV<       ' Adjust pupil location to just in front of the lens r0\?WoF2C       parID = FindFullName( "Geometry.Arizona Eye" ) }p=g*Zo*C;       eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) EWA;L?g|A       count = 0 qK?$=h.       While GetOperationCount(eID)>count cx{T  '1           GetOperation eID, count, op DR@1z9 a           If op.Type="ShiftZ" Then ^;r+W-MQ               DeleteOperation eID,count 1}}>Un`U5,               count=count-1 `B:"6nW6           End If o2aM#Q           count=count+1 \3aTaT?..       Wend *_1[[~Aw       op.Type = "ShiftZ" NG " yPn       op.val1 = taq-0.01 \gItZ}+c4}       op.parent = parID R"3 M[^       AddOperation eID, op -f9]v9|l   @A{m5 h       Print "Set pupil diameter = " & pupilDiam ;wR 'z$8   Z19m@vMsIP       'Update AZ Eye subassembly Description cwe1^SJ6y       eID = FindFullName( "Geometry.Arizona Eye" ) .'1SZe7O       GetEntity eID, entity OR4!YVVQ       entity.Description = "Accommodation = " & A & "D" 'eyJS`       SetEntity eID, entity YTQps&mD.   EB!daZH,       Update /syVGmS'M       Print "DONE!" ka/XK[/'        9JnY$e<&   End Sub LnFWA0y   gcf6\f}\<   如果屈光度是4，光瞳直径是4，则会输出如下数据： q+ pOrGh   so+4B1$)q   Accommodation = 4 Diopters 4Po)xo   Pupil Diameter = 4 mm gg^1b77hT   Set aqueous humor thickness = 2.81 nX^1$')gp   Set anterior lens radius = 10.4 and conic constant = -2.375869 zN~6HZ_:^   Set posterior lens radius = -4.424557 and conic constant = -3.081019 oY=1C}   Set lens thickness = 3.927 bA@P}M)X   Set lens index of refraction = 1.42672 P`jL]x   Set pupil diameter = 4 uLk]LT   DONE!

A&,,9G<

J!TBREK