Arizona眼睛模型

b(-t)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。 PG[O?l   A<X :K nl   模型 x][9ptrh   |SukiXJZF   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。 3nC#$L-    Table 1. AZ眼睛模型的定义 ^I~T$YjC '   )k] ! u   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=% C (    zn;Hs]G   光源 ^O Xr: P   ^npS==Y]!.   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。 To{G#QEgG   K(KP3 Q   图1. 光源和提示信息使用 pMZf!&tM   :Z]hI +7   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。 uQtk|)T E   h)l&K%4;   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。 {e[pSD6    图2. 字母F光源的设定方法光 \R>5F\ 0   n5*{hi   图3. 字母F在视网膜上位置点列图 |U$de2LF   mx(%tz^t   视网膜的散射 = EChH@3   ""v`0OP&J   在散射文件中，有一个名为“Retina surface”的72%的反射型朗伯散射，它为视网膜的散射提供了一个粗略的近似。为了模拟来自视网膜的散射，改变自定义元件“Eye ball” 下的视网膜的表面从“halt all” 到”Allow All”。并使几何中“plane”可追迹。 MD ?F1l"}%   cvXI]+`<3\   图4. 视网膜朗伯散射设定 -,fa{yt-   V_A,d8=lt   注意在视网膜的表面有散射重点采样规格定义，在“Scatter”标签的底部可获取该信息。“toward pupil”指定散射光朝向光瞳，半角度10度。 3auJ^B}   g=g.GpFt   图5. 视网膜重点采样规格设定 ]1|Ql*6y,   kl3S~gE4@   脚本 6n6VEwYj   m`\i+   内置脚本使用对话框显示屈光度和光瞳直径的数值设置。使用FRED Basic脚本创建和使用对话框非常容易。图6显示了如何获取用户自定义对话框，如下图所示： <,4R2'   图6. 用户对话框的创建与编辑 &Wz`>qYL*   图7. 用户对话框编辑器 *v nxP9<   @FdCbPl$   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。 !ga(L3vf   余下的脚本计算与屈光度有关的所有参数。 ,[}yf#8@J   )lDIzLp   分析 #u<oEDQ   F`BgKH!   屈光度为4，光瞳直径为4mm，字母F点在视网膜上所成的像。 ]D) 'I`   图7. 字母F在视网膜上颜色分析 K)Xs L   'K@{vB   脚本代码 +/!=Ub[:U   4j/iG\   Option Explicit     'Remove this to enable non-dimensioned variables to be used. d7_g u   aa0`y   Dim entity As T_ENTITY h\u0{!@}   Dim op As T_OPERATION ,y8I)+   Dim mat As T_MODELMATERIAL Z?~d']XD   Dim A As Double +>!B(j\gx   Dim pupilDiam As Double mj(&`HRs4   Dim eID As Long lR@i`)'?U   Dim parID As Long ZH;y>Z   Dim count As Integer 4$?wD <   Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double `Ge+(1x   Dim tlens As Double, nlens As Double 8G5)o`   Dim curv As Double, conic As Double i#]aV]IT   Dim ok As Long pe!dm}!h[   .?i-rTF:   Sub Main AJ#m6`M+EK   s=nVoc{Yt       '用户输入对话框 uFm+Y]h       Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 g * \P6           TextBox 220,21,40,21,.TextBox1 'default: 0 znQ'm^h           Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 aucZJjH           OKButton 40,91,90,21 2-$bh           CancelButton 190,91,90,21 uK;K{           Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 (!0j4'           TextBox 220,49,40,21,.TextBox2 'default: 4 V{T{0b"\U       End Dialog iBKb/Oi6       Dim dlg As UserDialog h5& /hBN   "^9[OgE:       ok = Dialog (dlg) y7M:b Uh   EREolCASb       If ok=0 Then    'cancel button was pressed 7>'uj7r]=           Print "Execution cancelled." "xDx/d8B           End w\o)bn       End If GP[6nw_'^   G%7 4v|cd       'Assign accommodation and pupil diameter & use defaults if field left empty FpdDIa       If dlg.TextBox1 = "" Then ] Wx>)LT           A = 0           'Default accommodation 6Iv(       Else f=:3!k,S           A = CDbl(dlg.TextBox1) fjIcB+Z       End If 6WE&((r^   VG<Hw{ c3r       If dlg.TextBox2 = "" Then Ic[}V0dk           pupilDiam = 4   'Default pupil diameter Gh]_L+       Else $=P WT-GIR           pupilDiam = CDbl(dlg.TextBox2) G}!7tU       End If 4AY _#f5u   ]a$Wxvgq       Print " " =zeFK_S!       Print "Accommodation = " & A & " Diopters" }O,U2=Hw`]       Print "Pupil Diameter = " & pupilDiam & " mm" /OQK/ t63   \!+-4,CbZY       ' Calculate new parameters with accommodation XYqpI/s       taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness O!+nF]V4f   .e`,{G(5q7       Rant = 12.0 - 0.4*A                     'Radius of anterior lens 24T@N~\g       CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens 4meidKw]   K -J|/eB       Rpost = -5.224557 + 0.2*A               'Radius of posterior lens ="uKWt6n'       CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens Sao>P[#x   I86e&"40       tlens = 3.767 + 0.04*A                  'Lens thickness t6'61*)|0   DE*MdfP0       nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction ],;D2]<s   Dh2:2Rz=#7       'Adjust parameters to account for accommodation gw_|C|!P   g3|B E2?       '************************************************************************* az0cS*@       'Aqueous thickness (Position of Lens) `IEq@Wr#$!       '************************************************************************* _9D|u<D       eID = FindFullName( "Geometry.Arizona Eye.Lens" ) :{[<g](       GetCustomElement eID, entity Dn~Z SrJ   P3'2IzNw       parID = FindFullName( "Geometry.Arizona Eye" ) ZlthYuJ   SHMl%mw       ' Delete any shift(s) in z IE&_!ce       count = 0 DdBxqkh       While GetOperationCount(eID)>count PC*m% ?+           GetOperation eID, count, op ~O \}/I28           If op.Type="ShiftZ" Then rmOQ{2}               DeleteOperation eID,count BjM+0[HC               count=count-1 >@^<S_KVh           End If >&bv\R/           count=count+1 t,RyeS/       Wend Tdg6kkJ   @u,+F0Yd       'Set new shift in S[vRw]*       op.Type = "ShiftZ" M]c7D`%s       op.val1 = taq e#tIk;9Xz       op.parent = parID m7JPH7P@BM       AddOperation eID, op *5e<\{!       Print "Set aqueous humor thickness = " & taq-0.55 GGH;Z WSe   u=%y       '************************************************************************* ]3}feU+       'Radius and conic constant of anterior lens !Q!&CG5l       '************************************************************************* -TgUyv.       eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) iAK/d)bq       GetConic eID, entity, curv, conic [eyb7\#    @: Z#E[N H       SetConic eID, entity, 1/Rant, CCant *|oPxQCtK       Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant `qE4U4   zhX;6= X2       '************************************************************************* T8U[xu.>       'Radius and conic constant of posterior lens V7:\q^$       '************************************************************************* K5{{:NR$       eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) 6J\q`q(W(       GetConic eID, entity, curv, conic \*uugw,\y   GMBJjP&R]       SetConic eID, entity, 1/Rpost, CCpost PB+\jj       Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost >PIPp7C   X tkw Z3       '************************************************************************* *<r%aeG$em       'Lens thickness (Position of posterior lens surface) ijFV<P       '************************************************************************* vO]J]][    FuuS"G,S       parID = FindFullName( "Geometry.Arizona Eye.Lens" ) 7,h3V=^)Q   \#++s&06       ' Delete any z-shift(s) "qS!B.rt:       count = 0 7H%_sw5S.       While GetOperationCount(eID)>count 3T1P$E" m           GetOperation eID, count, op bEd?^h           If op.Type="ShiftZ" Then ZOuR"9]               DeleteOperation eID,count 2 5Q+1               count=count-1 9<l-NU9 _           End If =UNT.]           count=count+1 `E W !-v)       Wend frc{>u~t   B9*Sfw%       'Set new z-shift Y%g "Y       op.Type = "ShiftZ" :G}DAUFN       op.val1 = tlens +*C^:^jA       op.parent = parID WNa3^K/W{       AddOperation eID, op IcFK,y%1       Print "Set lens thickness = " & tlens oIb) Rq!m   :CTL)ad2       '************************************************************************* f&c]LH_       'Lens index of refraction D#jX6       '************************************************************************* @Dj:4       eID = FindMaterial( "Lens" ) Xhse~=qA       GetModelMaterial eID, mat (B:uc_+   2h)8Fq_"       mat.Nd = nlens 4fty~0i=z       SetModelMaterial eID, mat 5 9i]       Print "Set lens index of refraction = " & nlens >rw"Rd'   sKd)BA0`       '************************************************************************* rz.IoQo       'Pupil diameter u s`}       '************************************************************************* N@()F&e        eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) -NzTqLBn   y9!:^kDI       'Adjust pupil diameter (trimming volume inner hole) f=m/ -mAA   6V2j*J       SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" {y6C0A*   U:n*<l-k}       ' Adjust pupil location to just in front of the lens h<Wg 3o       parID = FindFullName( "Geometry.Arizona Eye" ) =/9<(Tt%m       eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) o1k#."wHr       count = 0 p=B?/Sqa       While GetOperationCount(eID)>count -k{Jp/-D           GetOperation eID, count, op Dtt-|_EMS           If op.Type="ShiftZ" Then (6R4 \8z2               DeleteOperation eID,count iy j3QLqE               count=count-1 %S`ik!K"I           End If Hf%_}Du /`           count=count+1 WNF9#oN|oT       Wend 9p`r7:       op.Type = "ShiftZ" B< hEx@       op.val1 = taq-0.01 {|6z+vR       op.parent = parID ]"sRS`0+       AddOperation eID, op W:O0}   sPCMckt       Print "Set pupil diameter = " & pupilDiam e$wt&^W   y|sma;D       'Update AZ Eye subassembly Description eYEc^nC,c)       eID = FindFullName( "Geometry.Arizona Eye" ) jczq`yW       GetEntity eID, entity fsvYU0L       entity.Description = "Accommodation = " & A & "D" zvr\36       SetEntity eID, entity :JlDi>B   0S.?E.-&0       Update 4seciz0?       Print "DONE!" H]Wp%"L        #ElejQ|?   End Sub }V]eg,.BJ   T//S,   如果屈光度是4，光瞳直径是4，则会输出如下数据： LgHJo-+>   GMm'of#   Accommodation = 4 Diopters dJl^ADX[@   Pupil Diameter = 4 mm nwf7M#3d   Set aqueous humor thickness = 2.81 54q3R`y   Set anterior lens radius = 10.4 and conic constant = -2.375869 vg(K$o{BT   Set posterior lens radius = -4.424557 and conic constant = -3.081019 hhmGv9P   Set lens thickness = 3.927 yd>}wHt   Set lens index of refraction = 1.42672 )ooWQ-%P   Set pupil diameter = 4 Ei~f`{i   DONE!

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