Arizona眼睛模型

?~mw   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。 Jb~nu   . ] S{T   模型 `=]I-5#.W   &"90pBGK   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。 ?\HXYCi0r   Table 1. AZ眼睛模型的定义 {kLL&`ii   WHV]H   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. IT`r&;5   { .z6J)?J2   光源 BjT0mk"P   @ =RH_NB   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。 wYf9&}k\4   4_`ss+gk   图1. 光源和提示信息使用 u6~|].j R   8Nr,Wq   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。 W^c> (d</   t^|+|>S   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。 94=aVM\>>   图2. 字母F光源的设定方法光 ;2m<#~@0   ,{@,dw`lUz   图3. 字母F在视网膜上位置点列图 a\wpJ|3{=T   LnN6{z{M   视网膜的散射 ]M"l-A   oSb,)k@   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。 ;rSpM   #&Zb8HAj   图4. 视网膜朗伯散射设定 ar0y8>]3   sK#)wjj\^   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。 htn"rY(   G/F0 )M   图5. 视网膜重点采样规格设定 |eEcEu?/b   =H'7g6   脚本 1|za>N6[yu   [!@&t:A   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： I_Q*uH.Y5   图6. 用户对话框的创建与编辑 2:(h17So   图7. 用户对话框编辑器 kf3yJ P/   'RIlyH~Yf   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。 9zj^\-FA_l   余下的脚本计算与屈光度有关的所有参数。 @v1f)(N   MZt~ Abt   分析 {+V1>6   rYnjQr2a   屈光度为4，光瞳直径为4mm，字母F点在视网膜上所成的像。 2 {lo   图7. 字母F在视网膜上颜色分析 J%? 'Q{    %ZF6%m0S   脚本代码 WJG&`PP   d7xd"   Option Explicit     'Remove this to enable non-dimensioned variables to be used. 8 3*"58   mdu5aL   Dim entity As T_ENTITY Kt,ENbF   Dim op As T_OPERATION q?x.P2   Dim mat As T_MODELMATERIAL P^-tGo!   Dim A As Double } k[gR I]   Dim pupilDiam As Double b"+J8W   Dim eID As Long GS^U6Xef   Dim parID As Long $u"t/_%   Dim count As Integer gxpGi@5   Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double c&Pgz~iP   Dim tlens As Double, nlens As Double ,+0>p   Dim curv As Double, conic As Double N?d4Pu1m   Dim ok As Long < PoRnx   "{0 o"k   Sub Main tqY)   l\W[WQPh       '用户输入对话框 W s!N%%g       Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 hJ0)"OA5           TextBox 220,21,40,21,.TextBox1 'default: 0 kcd~`+C           Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 X@u-n_           OKButton 40,91,90,21 |V2+ 4b,           CancelButton 190,91,90,21 I|=$.i           Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 sa%2,e'           TextBox 220,49,40,21,.TextBox2 'default: 4 ;Ry )^5Q       End Dialog ~ #Gu:       Dim dlg As UserDialog h' OLj#H   YadY?o./       ok = Dialog (dlg) jI$}\*g   F`9;s@V*       If ok=0 Then    'cancel button was pressed oWVlHAPj           Print "Execution cancelled." pIh%5ZU           End j|f$:j       End If 28L3"c   Cc:m~e6r       'Assign accommodation and pupil diameter & use defaults if field left empty c43"o       If dlg.TextBox1 = "" Then ~%9ofXy           A = 0           'Default accommodation :%Dw3IrOM       Else Ws[[Me,=           A = CDbl(dlg.TextBox1) NJb5H oYZ       End If DXAA[hUjF   Hh=D:kE       If dlg.TextBox2 = "" Then `F:PWG`           pupilDiam = 4   'Default pupil diameter {q2H_H        Else ;b:Ct<           pupilDiam = CDbl(dlg.TextBox2) v>TI.;{y       End If 3Q^@!hu   z<~gv"       Print " " ?U]/4]       Print "Accommodation = " & A & " Diopters" dq?q(_9       Print "Pupil Diameter = " & pupilDiam & " mm" 7kM_Ijd$   |5SYKA7CS       ' Calculate new parameters with accommodation X]q,A5g       taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness ~:."BA   Z3=DM=V;v       Rant = 12.0 - 0.4*A                     'Radius of anterior lens MT" 2^&R       CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens 5fS89?/?   <Tr_,Ya{9       Rpost = -5.224557 + 0.2*A               'Radius of posterior lens TL(L[       CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens jcF/5u5e   f<ABs4w       tlens = 3.767 + 0.04*A                  'Lens thickness Zg%SE'kK   5H#3PZaQ       nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction ANh5-8y   e !}R1       'Adjust parameters to account for accommodation EAq/Yw2$   ,L&Ka|N0       '************************************************************************* %k#Q)zWJ       'Aqueous thickness (Position of Lens) Y7)YJI       '************************************************************************* >G<AyS&z*       eID = FindFullName( "Geometry.Arizona Eye.Lens" ) 6C>x,kU       GetCustomElement eID, entity ;pdW7   +<Ot@luE       parID = FindFullName( "Geometry.Arizona Eye" ) krm&.J   Nko;I?Fn       ' Delete any shift(s) in z +0;n t       count = 0 +O:Qw[BL/Z       While GetOperationCount(eID)>count P-ma~g>I           GetOperation eID, count, op 4RsV\Y{FN           If op.Type="ShiftZ" Then u79.`,Ad&               DeleteOperation eID,count NG@9}O               count=count-1 r7sPFM           End If Kd CPt!           count=count+1 N4"%!.Y       Wend d;\x 'h2   o<locZ       'Set new shift in 4O[T:9mn0       op.Type = "ShiftZ" RL r;]j8cm       op.val1 = taq \}t(g}7T       op.parent = parID z7F~;IB*u       AddOperation eID, op [Fe`}F}Co8       Print "Set aqueous humor thickness = " & taq-0.55 0Z#&!xTb   ;5-Sn(G       '************************************************************************* 2#5SI       'Radius and conic constant of anterior lens ~q#UH'=%       '************************************************************************* |_HH[s*U       eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) l"!.aIY"e       GetConic eID, entity, curv, conic pm O}m>   <T:u&Ic       SetConic eID, entity, 1/Rant, CCant YVZm^@ZVV       Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant ?G+v#?A   ZVEq{x1Zc       '************************************************************************* E N%cjvE       'Radius and conic constant of posterior lens T<~NB5&f       '************************************************************************* I(ds]E ;_E       eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) XX~~SvSM       GetConic eID, entity, curv, conic erYpeq.   )Z0pU\       SetConic eID, entity, 1/Rpost, CCpost ]~CGzV       Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost /og2+!   v" 6q!       '************************************************************************* '~%1p_0dq       'Lens thickness (Position of posterior lens surface) RvvK`}/6       '************************************************************************* tlu-zUsi   (F~ i       parID = FindFullName( "Geometry.Arizona Eye.Lens" ) \MQ|(   8.Wf^j$+{       ' Delete any z-shift(s) ZffK];D       count = 0 uG&xtN8       While GetOperationCount(eID)>count eiI}:5~ /g           GetOperation eID, count, op \kZxys!4           If op.Type="ShiftZ" Then Y<%$;fx$Sx               DeleteOperation eID,count rgdDkWLXC               count=count-1 2Q,e1'=           End If Ki{&,:@           count=count+1 aGx`ec*t       Wend `gfh]7T   Xa\{WM==;       'Set new z-shift !.H< dQS       op.Type = "ShiftZ" `omZ'n)       op.val1 = tlens C^XJE1D.       op.parent = parID tM <6c+       AddOperation eID, op ^aN;M\       Print "Set lens thickness = " & tlens EKhwrBj S   E(*RtOC<W       '************************************************************************* y[oc^Zuo       'Lens index of refraction /=A^@&:_#       '************************************************************************* [>Z~&cm       eID = FindMaterial( "Lens" ) )t{?7wy       GetModelMaterial eID, mat BV"7Wp;   EyA}       mat.Nd = nlens fB|rW~!v       SetModelMaterial eID, mat '@i/?rNi%N       Print "Set lens index of refraction = " & nlens 3|8\,fO?   =o;8xKj       '************************************************************************* AK%`EsI^       'Pupil diameter c#|!^gjf       '************************************************************************* "detDB        eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) 9^QiFgJy   ^.aFns{wv       'Adjust pupil diameter (trimming volume inner hole) n.n;'p9t@   `WGT`A"       SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" [U.3rcT"N   o(Yfnnuy       ' Adjust pupil location to just in front of the lens !E8y!|7$       parID = FindFullName( "Geometry.Arizona Eye" ) kL\ FY       eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) pZUckQ       count = 0 :{bvCos<)       While GetOperationCount(eID)>count Xd@  -           GetOperation eID, count, op c+,F)i^`           If op.Type="ShiftZ" Then RTHD 2               DeleteOperation eID,count !f[LFQD               count=count-1 "bZ%1)+           End If F=!p7msRB           count=count+1 q@8Jc[\d       Wend pyYm<dn       op.Type = "ShiftZ" {z>fe }       op.val1 = taq-0.01 k#X~+}N^       op.parent = parID EKo!vieG       AddOperation eID, op _rt+OzZ*L   Evu`e=LaG       Print "Set pupil diameter = " & pupilDiam 6RV42r^pf   ~Gm<F .(+       'Update AZ Eye subassembly Description o~<X c       eID = FindFullName( "Geometry.Arizona Eye" ) Z> Jm       GetEntity eID, entity 5IE3[a%X       entity.Description = "Accommodation = " & A & "D" Ey96XJV       SetEntity eID, entity j}O~6A>|   E#}OIZ\S       Update @i2"+_}*       Print "DONE!" +9Q,[)e r        '/M9V{DD88   End Sub v6=pV 4 k9   #$W02L8   如果屈光度是4，光瞳直径是4，则会输出如下数据： GPV=(}z   San3^uX   Accommodation = 4 Diopters *g7BR`Bt]z   Pupil Diameter = 4 mm mbT4K8<^   Set aqueous humor thickness = 2.81 `R[cM;c2   Set anterior lens radius = 10.4 and conic constant = -2.375869 v2eLH:6   Set posterior lens radius = -4.424557 and conic constant = -3.081019 1.Kun !w   Set lens thickness = 3.927 =D-u" .{   Set lens index of refraction = 1.42672 R(p`H}^   Set pupil diameter = 4 {<ms;Oi'   DONE!

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