Arizona眼睛模型

X]9<1[f   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。 "6IZf>N@#   b&@]f2/   模型 _t"[p_llo   P<Z` 8a[   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。 (Z @dz   Table 1. AZ眼睛模型的定义 Z3MhHvvgp{   QKEtV   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. 117lhx].'   gnzg(Y]5w   光源 '/XP4B\(E   '\d ldg#P   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。 a_/4^+   E@otV6Wk[@   图1. 光源和提示信息使用 huA?*fat    &/Gn !J;1   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。 pam9wfP   ;X]B0KFe7   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。 AH/^v;-   图2. 字母F光源的设定方法光 LCS.C(n,   ` ;mQ"lO   图3. 字母F在视网膜上位置点列图 R+ \%   ld#x'/   视网膜的散射 'bLP#TAzf   ID`C   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。 f U=P$s   "CC"J(&a   图4. 视网膜朗伯散射设定 xx1lEcj   E<tR8='F   注意在视网膜的表面有散射重点采样规格定义，在“Scatter”标签的底部可获取该信息。“toward pupil”指定散射光朝向光瞳，半角度10度。 t}I@Rmso   ]=ApYg7!   图5. 视网膜重点采样规格设定 Xu~N97\G   " wT?$E   脚本 H-&27?s^   oB!Y)f6H1   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： {T^D&i# o   图6. 用户对话框的创建与编辑 @i(9k   图7. 用户对话框编辑器 p{_*<"cfYn   QsxvA;7%   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。 ;p~!('{P   余下的脚本计算与屈光度有关的所有参数。 B*}]'   *^g]QQ   分析 .]KC*2   jyF*JQjK4   屈光度为4，光瞳直径为4mm，字母F点在视网膜上所成的像。 ORP<?SG55u   图7. 字母F在视网膜上颜色分析 h4KMhr   Y)lr+~84f   脚本代码 EUI*:JU-   aB (pdW4   Option Explicit     'Remove this to enable non-dimensioned variables to be used. "XV@OjrE   ^1c7\"{   Dim entity As T_ENTITY *X Wu)>*o   Dim op As T_OPERATION -Wmb M]Z   Dim mat As T_MODELMATERIAL re%XaL   Dim A As Double 5Hj/7~ =   Dim pupilDiam As Double Xl2g Hh   Dim eID As Long f^QC4hf0   Dim parID As Long *re?V9   Dim count As Integer =$bF[3D   Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double #E=8kbD7   Dim tlens As Double, nlens As Double RuVk>(?WK%   Dim curv As Double, conic As Double 1Zp/EYWa{   Dim ok As Long GK,{$SC+=   ZRc^}5}WA   Sub Main Z R=[@Oi   2+)h!y]       '用户输入对话框 |Fze9kZO       Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 _~CJitR3           TextBox 220,21,40,21,.TextBox1 'default: 0 9&zR i           Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 L.;x=w           OKButton 40,91,90,21 ;c]O*\/           CancelButton 190,91,90,21 r|ZB3L|7           Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 !wd wo0           TextBox 220,49,40,21,.TextBox2 'default: 4 p`7d9MV^       End Dialog Yz[Rl ^       Dim dlg As UserDialog &I)tI^P}   7;'UC','       ok = Dialog (dlg) lU=VCuW!   {W{;VJKQ2       If ok=0 Then    'cancel button was pressed `%#_y67v           Print "Execution cancelled." OOI p)=4           End Rl0"9D87z       End If .j,xh )v"   Mi(6HMA.SF       'Assign accommodation and pupil diameter & use defaults if field left empty X#0yOSR       If dlg.TextBox1 = "" Then T>1#SWQ/9           A = 0           'Default accommodation *]<=04v]R       Else tFn[U#'           A = CDbl(dlg.TextBox1) gzVZPvTPE       End If  Jn|<G   *wmkcifF;       If dlg.TextBox2 = "" Then rmvrv.$3           pupilDiam = 4   'Default pupil diameter ^fd*KM       Else E>*b,^J7g           pupilDiam = CDbl(dlg.TextBox2) `g(#~0R       End If _a"| :kX   CiHx.5TiC       Print " " B/lIn'=       Print "Accommodation = " & A & " Diopters" xA:;wV       Print "Pupil Diameter = " & pupilDiam & " mm" @|ZUyat   q 0>9T       ' Calculate new parameters with accommodation ,mCf{V]#       taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness V#b*:E.cA   >#mKM%T2MJ       Rant = 12.0 - 0.4*A                     'Radius of anterior lens T$r/XAs       CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens B&59c*K   .L#4#IO       Rpost = -5.224557 + 0.2*A               'Radius of posterior lens *1b0IQ$g       CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens ? B|i   Dn#5H{D-d       tlens = 3.767 + 0.04*A                  'Lens thickness XZ$g~r   '#j6ZC/?       nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction Dvz 6 E   oui0:V y<       'Adjust parameters to account for accommodation :u=y7[I   ]moBVRd       '************************************************************************* CP"5E?dcK       'Aqueous thickness (Position of Lens) MxGQM>       '************************************************************************* PPpaH!(D       eID = FindFullName( "Geometry.Arizona Eye.Lens" ) &l{ctP%q       GetCustomElement eID, entity Edh9=sxL   [.$%ti *!       parID = FindFullName( "Geometry.Arizona Eye" ) e>!]_B1ad   $[cB6       ' Delete any shift(s) in z Fgwe`[       count = 0 x3Fn'+       While GetOperationCount(eID)>count VOATza`           GetOperation eID, count, op 't(#HBU           If op.Type="ShiftZ" Then ;Cx`RF w               DeleteOperation eID,count R"t2=3K               count=count-1  xK1w->[           End If &V&beq4)p           count=count+1 5>1c4u`x       Wend FRPdfo37   Ug gg!zA       'Set new shift in =.m/X>       op.Type = "ShiftZ" k-s|gC4       op.val1 = taq oM#+Z qP       op.parent = parID  UiK)m:NU       AddOperation eID, op 2"Unk\Y       Print "Set aqueous humor thickness = " & taq-0.55 9*n?V;E   [["eK9}0       '************************************************************************* LG("<CU       'Radius and conic constant of anterior lens i}<fg*6@E       '************************************************************************* Pa|*Jcr       eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) ZL!5dT&@W       GetConic eID, entity, curv, conic rO1N@kd/   Iz#jR2:yn       SetConic eID, entity, 1/Rant, CCant vf?m6CMU!       Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant rF?QI*`Y(   nM8'="$       '************************************************************************* Ve"M8-{oKk       'Radius and conic constant of posterior lens R>[G6LOG       '************************************************************************* q8e]{sT'!       eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) [Q8vS;.       GetConic eID, entity, curv, conic -"Nvu   &)!N5Veb       SetConic eID, entity, 1/Rpost, CCpost 1F2(MKOo!       Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost BH$hd|KD<   U?:?NC=1{       '************************************************************************* !Xq5r8]       'Lens thickness (Position of posterior lens surface) _t X1z^       '************************************************************************* NPE 4@c_a@   ^v3J ld       parID = FindFullName( "Geometry.Arizona Eye.Lens" ) hx~rq`{   <{eJbNp       ' Delete any z-shift(s) a63Ud<_a7       count = 0 Fl==k       While GetOperationCount(eID)>count 1)-VlQK p           GetOperation eID, count, op O`>u70           If op.Type="ShiftZ" Then X4bZ4U*               DeleteOperation eID,count QT"o"B               count=count-1 V-dub{K           End If ZtI@$ An           count=count+1 ~!Rf5QA85       Wend &D7Mv5i0@   8feLhWg'P       'Set new z-shift cdL0<J b,       op.Type = "ShiftZ" ?Bd6<F-G       op.val1 = tlens  /EZ -       op.parent = parID [&p/7       AddOperation eID, op %W2 o`W$       Print "Set lens thickness = " & tlens BDi+*8   [Z]C BEE       '************************************************************************* c8o2* C$       'Lens index of refraction kxY9[#:<fB       '************************************************************************* l p1GK/!s       eID = FindMaterial( "Lens" ) 6ZC~q=my       GetModelMaterial eID, mat GRgpy   llpgi,-=       mat.Nd = nlens .7Itbp6=R       SetModelMaterial eID, mat t1o_x}z4.       Print "Set lens index of refraction = " & nlens V67<Ky>   cMAY8$       '************************************************************************* *.-qbwOg       'Pupil diameter 3pkx3tp{       '************************************************************************* }~ga86:n0       eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) %cq8%RT   R+=Xr<`%U|       'Adjust pupil diameter (trimming volume inner hole) `S]DHxS   6?l|MU"Q.       SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" Ec!R3+   _&$nJu       ' Adjust pupil location to just in front of the lens B,{Q[       parID = FindFullName( "Geometry.Arizona Eye" ) F:G Vysy       eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) ]ex2c{ G       count = 0 kE{-h'xADD       While GetOperationCount(eID)>count ;.d{$SO           GetOperation eID, count, op g+ cH           If op.Type="ShiftZ" Then \'P79=AU               DeleteOperation eID,count v-}D>)M^W               count=count-1 IOH6h=           End If aN"dk-eK           count=count+1 EvDg{M}       Wend YM +4:P2       op.Type = "ShiftZ" Z+S1e~~       op.val1 = taq-0.01 t[bZg9;       op.parent = parID n'<F'1SWv       AddOperation eID, op l]geQl:7`r   m^1'aO_;q       Print "Set pupil diameter = " & pupilDiam {9h`h08?z   wB%;O`Oh       'Update AZ Eye subassembly Description q>dERN&       eID = FindFullName( "Geometry.Arizona Eye" ) }H9V$~}@-       GetEntity eID, entity I!g+K       entity.Description = "Accommodation = " & A & "D" O['5/:-       SetEntity eID, entity zWq&HBs   )9V8&,       Update RjG=RfB'V       Print "DONE!" e\H1 IR3        Ccy0!re   End Sub ne'Y{n(8%   G/_9!lE   如果屈光度是4，光瞳直径是4，则会输出如下数据： [kPF Jf   ?lQ-HOAw   Accommodation = 4 Diopters s!j vBy   Pupil Diameter = 4 mm -f%J_`   Set aqueous humor thickness = 2.81 Vg8c} >7   Set anterior lens radius = 10.4 and conic constant = -2.375869 N5@l[F7I   Set posterior lens radius = -4.424557 and conic constant = -3.081019 690;\O '   Set lens thickness = 3.927 "5$2b>_UE   Set lens index of refraction = 1.42672 4*_.m9{   Set pupil diameter = 4 #s|/5[i   DONE!

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