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2020-12-09 09:18 |
Arizona眼睛模型
简介 @{IX
do 1Lf - 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。 F[coa5 !*c%Dj 模型 q}_8iDO6 yFAUD
ro 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。 bD
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Table 1. AZ眼睛模型的定义 Idu'+O4 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. w8+phN(-M r`ftflNh( 光源 9+(b7L w%wVB/( 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。 rv{ Wti[ |$tF{\ 9uxoMjR-
图1. 光源和提示信息使用 =>S[Dh 除了“Letter F”之外的所有光源的光线位置设定在了孔径光阑位置处,并增加了pre-propagation distance= -8。尽管光线在光瞳处创建,规定的传输方向相对于光线位置在pre-propagation distance之后。这意味着光束沿着Z轴在眼睛的前面以平行光入射,而不是在光瞳处入射。 l%V+]skS |3k r*# 在往下看是内置的脚本用来修改屈光度,使其为4(250mm),光源“Letter F”在视网膜处生成一个字母为F的图像。绿色的光线聚焦的非常好而红色和蓝色光线有一点的模糊。使用Positions Spot Diagram分析工具来观察最为合适。 ZW))Mx#K=T ~e|E5[-i
图2. 字母F光源的设定方法光 }G(#jOYk k Jz^\Re
图3. 字母F在视网膜上位置点列图 [?6+ r 视网膜的散射 Fp B3SJ6 B .&u
@-Vm 在散射文件中,有一个名为“Retina surface”的72%的反射型朗伯散射,它为视网膜的散射提供了一个粗略的近似。为了模拟来自视网膜的散射,改变自定义元件“Eye ball” 下的视网膜的表面从“halt all” 到”Allow All”。并使几何中“plane”可追迹。 m!INbIh aAcQmq TT &xr (Kb
图4. 视网膜朗伯散射设定 A/ zAB3 注意在视网膜的表面有散射重点采样规格定义,在“Scatter”标签的底部可获取该信息。“toward pupil”指定散射光朝向光瞳,半角度10度。 Z{u]qI{l L]YJ#5 UJS
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图5. 视网膜重点采样规格设定 9a:(ab' 脚本 An]Vx<PD = m|<~t 内置脚本使用对话框显示屈光度和光瞳直径的数值设置。使用FRED Basic脚本创建和使用对话框非常容易。图6显示了如何获取用户自定义对话框,如下图所示: pl}W|kW} XcbEh
图6. 用户对话框的创建与编辑 DW,Z})9
图7. 用户对话框编辑器 shLMj)7! 如果“OK”按钮按下,将会核对对话框下面的代码行,如果点击取消则脚本终止。然后输入的参数赋予变量,如果此处是保留为空白,则使用默认值。因此,如果没有值输入并点击“OK”按钮,则脚本是以屈光度为0,光瞳直径为4mm来运行的。 p>U= Jg 余下的脚本计算与屈光度有关的所有参数。 {DVMs|5;^ V%*91t _ 分析 2(Xu?W 7d g6gwNC:aF 屈光度为4,光瞳直径为4mm,字母F点在视网膜上所成的像。 2*W|s7cc 9r:|u:i7m
图7. 字母F在视网膜上颜色分析 ;Gu(Yoa}y 脚本代码 .'
v$PEy U+-;(Fh~ Option Explicit 'Remove this to enable non-dimensioned variables to be used. AO-~dV -f'&JwE0= Dim entity As T_ENTITY ,\T `gh Dim op As T_OPERATION sCf)#6mI Dim mat As T_MODELMATERIAL RP^L.X(7^ Dim A As Double ?J| Dim pupilDiam As Double O*F= xG Dim eID As Long TPj,4&| Dim parID As Long Zirp_[KZ% Dim count As Integer D7IhNWrgj Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double ^]/V-!j Dim tlens As Double, nlens As Double \+
Ese-la Dim curv As Double, conic As Double cI6Td*vM Dim ok As Long -lfbn=3 nh+h3"-d Sub Main (j%"iQD DEPsud ; '用户输入对话框 6m:$RW Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 H ~<.2b TextBox 220,21,40,21,.TextBox1 'default: 0 {\h:k\k Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 1Si$Q OKButton 40,91,90,21 vgn,ZcX CancelButton 190,91,90,21 )|]*"yf:E Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 9+Wf*:*EW TextBox 220,49,40,21,.TextBox2 'default: 4 eS%8WmCV9< End Dialog 3z k},8fu Dim dlg As UserDialog Z0 c|; M^n^wz ok = Dialog (dlg) T0o0_R <pFbm If ok=0 Then 'cancel button was pressed /BS yanro Print "Execution cancelled." R2Q1Rk# End q:wz!~(> End If =+VDb5= TV }+:X= @Z@ 'Assign accommodation and pupil diameter & use defaults if field left empty 8qUNh# If dlg.TextBox1 = "" Then #8WHIDS> A = 0 'Default accommodation wF-H{C' Else Kciz^)'Z A = CDbl(dlg.TextBox1) tt&{f <* End If nwi8>MG F:Yp1Wrb < If dlg.TextBox2 = "" Then DnCIfda2g pupilDiam = 4 'Default pupil diameter j^/^PUR Else B?d+^sz] pupilDiam = CDbl(dlg.TextBox2) y=}o|/5" End If ,9buI=' XS>( Bu Print " " _]< Tv3]RK Print "Accommodation = " & A & " Diopters" <.
V*]g/; Print "Pupil Diameter = " & pupilDiam & " mm" S:cd'68D *b`1+~p_2 ' Calculate new parameters with accommodation wk2Ff*& taq = 0.55 + 2.97 - 0.04*A 'Aqueous thickness 0<Rq Rf!$n7& \ Rant = 12.0 - 0.4*A 'Radius of anterior lens +[V.yY/t|> CCant = -7.518749 + 1.285720*A 'Conic constant of anterior lens N8*QAekN
yi<H }& Rpost = -5.224557 + 0.2*A 'Radius of posterior lens IRsyy\[kp8 CCpost = -1.353971 - 0.431762*A 'Conic constant of posterior lens |-]'~@~ EiPOY' tlens = 3.767 + 0.04*A 'Lens thickness .aC/ g?U 4@jX{{^6% nlens = 1.42 + 0.00256*A - 0.00022*A^2 'Lens index of refraction 8&y#LeM1TT F ^)(
7}ph 'Adjust parameters to account for accommodation `cFNO: 2}9M7Z",2 '************************************************************************* e'3y^Vg 'Aqueous thickness (Position of Lens) FD8d-G '************************************************************************* R E9`T eID = FindFullName( "Geometry.Arizona Eye.Lens" ) !!)NER-dv GetCustomElement eID, entity X(;WY^i! @,q <CF@Y parID = FindFullName( "Geometry.Arizona Eye" ) M
~6$kT T=[/x= ' Delete any shift(s) in z pvdCiYo1r count = 0 1+Q@RiW While GetOperationCount(eID)>count /kqa|=-`q GetOperation eID, count, op N}'2GBqfU4 If op.Type="ShiftZ" Then 15kkf~Z<t DeleteOperation eID,count Hw,@oOh. count=count-1 oUL4l=dj. End If To,*H OP count=count+1 R-Gg= l5 Wend
[$`%ve L1QDA}6?_Y 'Set new shift in ufocj1IU op.Type = "ShiftZ" eI/5foA op.val1 = taq T:*l+<? op.parent = parID =F46v{la AddOperation eID, op OgCz[QXr_ Print "Set aqueous humor thickness = " & taq-0.55 ^(Wu$\SA V=H :`n3k '************************************************************************* -o@L"C> 'Radius and conic constant of anterior lens SL`nt '************************************************************************* 3qy4nPg eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) X?'pcYSL GetConic eID, entity, curv, conic MAL;XcRR 9D7i>e%,;- SetConic eID, entity, 1/Rant, CCant gCx#&aXS Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant `r&]Ydu: G|z%T`!U1; '************************************************************************* a2eE!I 'Radius and conic constant of posterior lens c'wU$xt.w '************************************************************************* *eMMfxFl eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) ^`bMFsP GetConic eID, entity, curv, conic <sls1, |u+!CR SetConic eID, entity, 1/Rpost, CCpost /Edq[5Ah Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost kG`&Z9P @DSKa` '************************************************************************* EKEJ9Y+47H 'Lens thickness (Position of posterior lens surface) zxeT{AFPr? '************************************************************************* f'TEua_` N t\ZM parID = FindFullName( "Geometry.Arizona Eye.Lens" ) ZKai*q4? #tA/)Jvi ' Delete any z-shift(s) @]Lu"h#u= count = 0 a`>H69(bU While GetOperationCount(eID)>count bbT$$b- GetOperation eID, count, op 664D5f#EJ If op.Type="ShiftZ" Then .sD=k3d DeleteOperation eID,count 5t-,5 count=count-1 |mcc?*%t8 End If ]88qjKL count=count+1 <jBRUa[j_ Wend G"h}6Za;DO wZWAx 'Set new z-shift 9+3 VK op.Type = "ShiftZ" .AZwVP< op.val1 = tlens tTWEhHQ` op.parent = parID B:Hr{%O AddOperation eID, op I+
Y{_yw"f Print "Set lens thickness = " & tlens OsKtxtLO lX"6m}~D '************************************************************************* /*MioaQB}p 'Lens index of refraction b7B|$T, '************************************************************************* uaZHM@D eID = FindMaterial( "Lens" )
w"C,oo3 GetModelMaterial eID, mat Nnq1&j"m gFsqCx<q mat.Nd = nlens O&,8X-Ix SetModelMaterial eID, mat zjOOEvi Print "Set lens index of refraction = " & nlens tS-gaT`T x,ZF+vE '************************************************************************* P>(FCX 'Pupil diameter kpxGC,I^*. '************************************************************************* Q!_d6-*u eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) wxYGr`f "lSh4X 'Adjust pupil diameter (trimming volume inner hole) /aIGq/;Y+a {8h[Bd SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" [bRE=Zr$Ry ?'_6M4UKa ' Adjust pupil location to just in front of the lens uqLP$At parID = FindFullName( "Geometry.Arizona Eye" ) b'Km-'MtH eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) e5
}amrz count = 0 Keem\/ While GetOperationCount(eID)>count v*%52_ GetOperation eID, count, op l qKj;' If op.Type="ShiftZ" Then T5z]=Pd"^ DeleteOperation eID,count 5{Q9n{dOh count=count-1 'C]Yh."u End If >##Z}auY count=count+1 ,~DV0#" Wend A+3SLB op.Type = "ShiftZ" 0[e!/*_V op.val1 = taq-0.01 LD1&8kJ*l op.parent = parID aYDo0?kF' AddOperation eID, op hidQO h ,[)l>!0\H Print "Set pupil diameter = " & pupilDiam M&/%qF15 Fk^N7EJ:$ 'Update AZ Eye subassembly Description 4QTHBT+2` eID = FindFullName( "Geometry.Arizona Eye" ) `G_~zt/ GetEntity eID, entity G]4Ca5;Z!N entity.Description = "Accommodation = " & A & "D" Fj]06~u SetEntity eID, entity ~f[ Y; @Z2np{X: Update >0W
P:-\* Print "DONE!" >7zC-3 -*z7`]5J End Sub Fx|`0LI+C _DH^ K9,9 如果屈光度是4,光瞳直径是4,则会输出如下数据: R TpNxr{[ ,G g;:)k\ Accommodation = 4 Diopters -Ep#q&\ Pupil Diameter = 4 mm U||GeEd Set aqueous humor thickness = 2.81 Kk6=61} A Set anterior lens radius = 10.4 and conic constant = -2.375869 p @nj6N.-- Set posterior lens radius = -4.424557 and conic constant = -3.081019 qz{9ND|) Set lens thickness = 3.927 ir/uHN@ Set lens index of refraction = 1.42672 {(!JYz~P Set pupil diameter = 4 vg1JN"S[ DONE! pCA`OP);= b5LToy: 7J!s"|VS QQ:2987619807 KE@+I.x
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