Arizona眼睛模型
简介 ,sl.:C 4 FQ)Ekss~C 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。 <);u]0 I
GtH<0Du 模型 >GUTno$J >C3 9`1 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。
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Table 1. AZ眼睛模型的定义 u;g}N'" 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. @R{&>Q:. a<.@+sj{ 光源 Y|nTc.A 7SZs/wWh% 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。 p~ItHwiT _0E,@[ $7YLU{0
图1. 光源和提示信息使用 ^umAfk5r?H 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。 ek!N eu>
GXVGU-br 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。 mH .I! RA/yvr
图2. 字母F光源的设定方法光 g\'84:*J\ s.
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图3. 字母F在视网膜上位置点列图 MsQS{ok+ 视网膜的散射 B.#0kjA} Cx~z^YP' 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。 Z9I./s9 $@;[K\ bxq`E!]
图4. 视网膜朗伯散射设定 -NeF6 注意在视网膜的表面有散射重点采样规格定义,在“Scatter”标签的底部可获取该信息。“toward pupil”指定散射光朝向光瞳,半角度10度。 UUq9UV-h %xz02$k K%B i8d
图5. 视网膜重点采样规格设定 a mgex$ 脚本 |\t_I~de
=`H(`2 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: ]du~V?N
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图6. 用户对话框的创建与编辑 "o^zOU
图7. 用户对话框编辑器 CuNHDYQ&3 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}*hodzF 余下的脚本计算与屈光度有关的所有参数。 r%i{a 1S:H!h3 分析 LlJvuQ 28 WAbhBA 屈光度为4,光瞳直径为4mm,字母F点在视网膜上所成的像。 9nE%r\H 04t_
图7. 字母F在视网膜上颜色分析 ZxWV,s&p 脚本代码 }I]q$3. XjbK!. Option Explicit 'Remove this to enable non-dimensioned variables to be used. a\MJbBXv hlZjk0ez Dim entity As T_ENTITY t {}1f Dim op As T_OPERATION psVRdluS Dim mat As T_MODELMATERIAL O"Q=66.CR Dim A As Double l M$7/ Dim pupilDiam As Double x!+a,+G Dim eID As Long xj<SnrrC]u Dim parID As Long G'Y|MCKz> Dim count As Integer VbYapPu4b! Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double )LG/n Dim tlens As Double, nlens As Double 9^tyjX2 Dim curv As Double, conic As Double j>iM(8`t1 Dim ok As Long '4rgIs3=x" o%a$m9I Sub Main `UR.Rn/x nj[6c '用户输入对话框 D[mYrWHpn Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 J,7\/O(`A TextBox 220,21,40,21,.TextBox1 'default: 0 N.?Wev{ Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 Lnzhs;7L OKButton 40,91,90,21 'Vd>"ti CancelButton 190,91,90,21 m78PQx
H Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 iu 'yB TextBox 220,49,40,21,.TextBox2 'default: 4 /<@tbZJ*8 End Dialog ]nh)FMo Dim dlg As UserDialog u(R`}C?P' ;b^@o,= ok = Dialog (dlg) 809-p_)B Sa0\93oa If ok=0 Then 'cancel button was pressed -_3.]o/J Print "Execution cancelled." !`gg$9 End &}r932 End If y[cAU:P? 0U<9=[~q7@ 'Assign accommodation and pupil diameter & use defaults if field left empty z!%}0 If dlg.TextBox1 = "" Then ~VKw%WK A = 0 'Default accommodation
]%." Else gS%J`X$ A = CDbl(dlg.TextBox1) GCoqKE
End If ?6Gq & seq$] If dlg.TextBox2 = "" Then >nxtQ pupilDiam = 4 'Default pupil diameter _?ym,@}# Else .jCdJ
=z pupilDiam = CDbl(dlg.TextBox2) e|I5Nx2) End If C9h8d
3Wiu`A Print " " Q|>y2g! Print "Accommodation = " & A & " Diopters" i<
ih : Print "Pupil Diameter = " & pupilDiam & " mm" XxIU B(.QI eR/7*G5 ' Calculate new parameters with accommodation W+S>/`N taq = 0.55 + 2.97 - 0.04*A 'Aqueous thickness w3*JVIQC <1y%ch; Rant = 12.0 - 0.4*A 'Radius of anterior lens d+(~{xK: CCant = -7.518749 + 1.285720*A 'Conic constant of anterior lens (w.B_9# -+L1Hid.7 Rpost = -5.224557 + 0.2*A 'Radius of posterior lens 4&\m!s
CCpost = -1.353971 - 0.431762*A 'Conic constant of posterior lens R:E` $j:0*Z=> tlens = 3.767 + 0.04*A 'Lens thickness "Xm'(c( 'g#))y nlens = 1.42 + 0.00256*A - 0.00022*A^2 'Lens index of refraction [\!S-: "x{S3v4Rb5 'Adjust parameters to account for accommodation cX*^PSM ~&pk</Dl '************************************************************************* -x7L8Wj 'Aqueous thickness (Position of Lens) W46sKD;\^W '************************************************************************* MV/JZ;55 eID = FindFullName( "Geometry.Arizona Eye.Lens" ) !} 1p:@ GetCustomElement eID, entity GB-=DC6 a^2?W parID = FindFullName( "Geometry.Arizona Eye" ) mBNa;6w?{* Ei#"r\q j_ ' Delete any shift(s) in z *mYec~ count = 0 f.,-KIiF While GetOperationCount(eID)>count K1Tzy=Z9j GetOperation eID, count, op lU@ni(69d If op.Type="ShiftZ" Then 3}H94H)]a DeleteOperation eID,count a`T{5*@ count=count-1 tDi<n} End If 39OZZaWL count=count+1 .G^.kg , Wend #i~.wQ$1 ]Z~H9!%t 'Set new shift in _+UD>u{ op.Type = "ShiftZ" nI6`/ op.val1 = taq F
Hv|6zUX op.parent = parID Tj>~#~ AddOperation eID, op lVqvS/_k$ Print "Set aqueous humor thickness = " & taq-0.55 6Up,B=sX0 %
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5hC9 '************************************************************************* sI~{it# 'Radius and conic constant of anterior lens r`"
? K]rI '************************************************************************* yXDf;`J eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) $
@^n3ZQ4 GetConic eID, entity, curv, conic p<$z!|7m N &=,)d~M SetConic eID, entity, 1/Rant, CCant #fa~^]EM] Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant g6N{Z e Wg 8zr)oQ: '************************************************************************* 0BD3~Lv 'Radius and conic constant of posterior lens d(h`bOjI '*************************************************************************
|,.glL eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) -PxA~((g5 GetConic eID, entity, curv, conic ?p/i}28=y E9|i: SetConic eID, entity, 1/Rpost, CCpost )(,+o Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost |,qz7dpe bj7v <G|Y '************************************************************************* %[RLc[pB 'Lens thickness (Position of posterior lens surface) 1MOQ/N2BR '************************************************************************* wWwY.}j 5 J 0 parID = FindFullName( "Geometry.Arizona Eye.Lens" ) +`\C_i- @
j'I ' Delete any z-shift(s) O"Ar3> count = 0 Q~uj:A]n< While GetOperationCount(eID)>count GCc@
:*4[ GetOperation eID, count, op xAsbP$J: If op.Type="ShiftZ" Then l^fz DeleteOperation eID,count .4U::j} count=count-1 m\j'7mZ1 End If 1J^{h5?lU count=count+1 1 [dza5 Wend Io|
72W}rg U2!9Tl9". 'Set new z-shift voCQ_~*)9 op.Type = "ShiftZ" !x|Ok'izDL op.val1 = tlens .|cQ0:B[ op.parent = parID '%kk&&3' AddOperation eID, op /)6<`S( Print "Set lens thickness = " & tlens d&t|Y:,8 C2FewsRz '************************************************************************* |odl~juU 'Lens index of refraction ]M>mwnt+ '************************************************************************* ,D>$N3; eID = FindMaterial( "Lens" ) Hb IRE GetModelMaterial eID, mat 7+=fD|Cl $5|/X&"O)/ mat.Nd = nlens a+IU<O-J? SetModelMaterial eID, mat :jgwp~l Print "Set lens index of refraction = " & nlens < JA5.6<= H 2\KI( '************************************************************************* =((#k DrN 'Pupil diameter {dhG SM7 '************************************************************************* &`GQS| eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) or>5a9pj vfm|?\ 'Adjust pupil diameter (trimming volume inner hole) \Ua"gS2L -@e9!/GP, SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" (?D47^F & \A
Y7%> ' Adjust pupil location to just in front of the lens I[G<aI! parID = FindFullName( "Geometry.Arizona Eye" ) Whod_Uk eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) p'ukV(B count = 0 #GY;., While GetOperationCount(eID)>count C]p3,G,oN GetOperation eID, count, op *h$Z:p-g If op.Type="ShiftZ" Then +QqYf1@F DeleteOperation eID,count 2/x+7F}w5 count=count-1 D~G24k6b3 End If >y
&9!G count=count+1 O3PE
w4yA Wend Ft#d&
I op.Type = "ShiftZ" 8$BZbj%?hx op.val1 = taq-0.01 98x]x:mgI_ op.parent = parID p{[Ol AddOperation eID, op =i4 Ds )E'iC Print "Set pupil diameter = " & pupilDiam ZC@sUj" MyXgp>?~T 'Update AZ Eye subassembly Description lrPiaSO`I eID = FindFullName( "Geometry.Arizona Eye" ) ~8o's` GetEntity eID, entity S9U,so? entity.Description = "Accommodation = " & A & "D" TG~:Cmc SetEntity eID, entity "}Of f eR4%4gW) Update m(L]R(t Print "DONE!" dd@qk`Zl&A 1D sgU6" End Sub G>qzAgA Y.$'<1 如果屈光度是4,光瞳直径是4,则会输出如下数据: pdX%TrM+[: DBI[OG9 Accommodation = 4 Diopters "qYPi Pupil Diameter = 4 mm iP6$;Y{ZA Set aqueous humor thickness = 2.81 |[7xTD Set anterior lens radius = 10.4 and conic constant = -2.375869 ggR@& \ Set posterior lens radius = -4.424557 and conic constant = -3.081019 gBA
UrY%] Set lens thickness = 3.927 , |,DXw Set lens index of refraction = 1.42672 nlQ<Aa-% Set pupil diameter = 4 t9685s DONE! q$ (@ %6}S1fuA {7LO|E}7 QQ:2987619807 T0J"Wr>WY
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