-
UID:317649
-
- 注册时间2020-06-19
- 最后登录2026-07-17
- 在线时间1977小时
-
-
访问TA的空间加好友用道具
|
简介 _REAzxeS V D.T=( 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。 xw~3x*{ N2$uw@s 模型 @$!rgLyL[ /=S\v<z 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。 UA(&_-C\ Q>
J9M`a Table 1. AZ眼睛模型的定义 Wr;9Mz&{ 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. b+e9Pi*\ i{4J$KT 光源 t lpTq\; ?[c{pb,| 多个光源定义来分析该模型的不同特性。图1显示了所以的光源和提示信息告诉您他们可以用来做什么。 {&0u:
W|AK"vf *`~]XM@H 图1. 光源和提示信息使用 l3HfaCP6: 除了“Letter F”之外的所有光源的光线位置设定在了孔径光阑位置处,并增加了pre-propagation distance= -8。尽管光线在光瞳处创建,规定的传输方向相对于光线位置在pre-propagation distance之后。这意味着光束沿着Z轴在眼睛的前面以平行光入射,而不是在光瞳处入射。 tM3Q;8gB! Oe"nNvu/ 在往下看是内置的脚本用来修改屈光度,使其为4(250mm),光源“Letter F”在视网膜处生成一个字母为F的图像。绿色的光线聚焦的非常好而红色和蓝色光线有一点的模糊。使用Positions Spot Diagram分析工具来观察最为合适。 cE+Y#jB ['Y"6[1 图2. 字母F光源的设定方法光 >h{)7Hv D&!c7_ ^ 图3. 字母F在视网膜上位置点列图 Vi'zSR28Z 视网膜的散射 L^xh5{ _DLELcH
Y 在散射文件中,有一个名为“Retina surface”的72%的反射型朗伯散射,它为视网膜的散射提供了一个粗略的近似。为了模拟来自视网膜的散射,改变自定义元件“Eye ball” 下的视网膜的表面从“halt all” 到”Allow All”。并使几何中“plane”可追迹。 uG=~kO A#8J6xcSrL \t?rHB3" 图4. 视网膜朗伯散射设定 *1g3,NMA 注意在视网膜的表面有散射重点采样规格定义,在“Scatter”标签的底部可获取该信息。“toward pupil”指定散射光朝向光瞳,半角度10度。 XS=f>e1<W @|EWif| %Z+FX,AK 图5. 视网膜重点采样规格设定 ky@ZEp= 脚本 usR+ZQaA P`AW8Y6o 内置脚本使用对话框显示屈光度和光瞳直径的数值设置。使用FRED Basic脚本创建和使用对话框非常容易。图6显示了如何获取用户自定义对话框,如下图所示: mKuY=#R P 7[ZoUWx 图6. 用户对话框的创建与编辑 Q)2i{\GPVn 图7. 用户对话框编辑器 |./{,", 如果“OK”按钮按下,将会核对对话框下面的代码行,如果点击取消则脚本终止。然后输入的参数赋予变量,如果此处是保留为空白,则使用默认值。因此,如果没有值输入并点击“OK”按钮,则脚本是以屈光度为0,光瞳直径为4mm来运行的。 !24PJ\~I 余下的脚本计算与屈光度有关的所有参数。 Nj=0bg"Qg5 6 l7iX] 分析 *=X61`0 Of
m0{c= 屈光度为4,光瞳直径为4mm,字母F点在视网膜上所成的像。 rUh2[z8: ^X ~S}MX 图7. 字母F在视网膜上颜色分析 2hsRYh 脚本代码 W5Vh+'3
z-_$P)[c Option Explicit 'Remove this to enable non-dimensioned variables to be used. <RuLIu SA%uGkm:e Dim entity As T_ENTITY m{f+! Dim op As T_OPERATION #@L5yy2 Dim mat As T_MODELMATERIAL PFjh]/= Dim A As Double ^J'O8G$ Dim pupilDiam As Double ca<OG;R^ Dim eID As Long LjCUkbzQF Dim parID As Long 7ygz52 Dim count As Integer QXEz[R Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double 9D]bCi\ Dim tlens As Double, nlens As Double lf#5X)V Dim curv As Double, conic As Double TjicltQi4 Dim ok As Long >~jl0!2z@ IO7cRg'-F Sub Main ('Ha$O72 8Y [4JXUK '用户输入对话框 s*R UYx Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 VUC_|=?dL TextBox 220,21,40,21,.TextBox1 'default: 0 YRQ?:a{H Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 >dXB)yl OKButton 40,91,90,21 )M*Sg?L CancelButton 190,91,90,21 XZT|ID_u" Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 'LYN{ TextBox 220,49,40,21,.TextBox2 'default: 4 !uP8powO End Dialog :9f 9Z7M Dim dlg As UserDialog |h& q Vg}+w Nt5 ok = Dialog (dlg) v%7Gh-P M[cAfu If ok=0 Then 'cancel button was pressed XZrzG P( Print "Execution cancelled." w|f@sB>j End duc\/S' End If ET(/h/r 6Ev+!!znu 'Assign accommodation and pupil diameter & use defaults if field left empty m -0}Pe9L If dlg.TextBox1 = "" Then 9Zr6 KA{ A = 0 'Default accommodation x"A\Z-xxz Else ,/Q`gRBh" A = CDbl(dlg.TextBox1) qv[w
1;U" End If NR"C@3kD]o A@Cvx7X If dlg.TextBox2 = "" Then z{/#/,V5D4 pupilDiam = 4 'Default pupil diameter KQ0f2? Else E {UhM q7 pupilDiam = CDbl(dlg.TextBox2) WW-}c;cnK End If ?*6Q;.f< iD/+#UTY Print " " vhzz(UPUt Print "Accommodation = " & A & " Diopters" Q.Y6 Print "Pupil Diameter = " & pupilDiam & " mm" _&[ -< cu r{f$n ' Calculate new parameters with accommodation iLN O}EUL taq = 0.55 + 2.97 - 0.04*A 'Aqueous thickness #mD_<@@ 0}M'> Rant = 12.0 - 0.4*A 'Radius of anterior lens 2InM(p7j~K CCant = -7.518749 + 1.285720*A 'Conic constant of anterior lens !wC(
]Y ,+X:#$ Rpost = -5.224557 + 0.2*A 'Radius of posterior lens op3a*KG CCpost = -1.353971 - 0.431762*A 'Conic constant of posterior lens uX6p^KNm5 } ?MbU6" tlens = 3.767 + 0.04*A 'Lens thickness AmJdZs|/ ?5F;4oR2g nlens = 1.42 + 0.00256*A - 0.00022*A^2 'Lens index of refraction "whs?^/ :w)9(5 'Adjust parameters to account for accommodation ED);2*qP} 7jGfQ '************************************************************************* *?A!`JpJn 'Aqueous thickness (Position of Lens) =CO'LyG '************************************************************************* ( X+2vN eID = FindFullName( "Geometry.Arizona Eye.Lens" ) dF5y'
R' GetCustomElement eID, entity OGO\u# ?Ss~!38 parID = FindFullName( "Geometry.Arizona Eye" ) B~b
='jN i~)EUF ' Delete any shift(s) in z 1$^r@rP count = 0 Bn.5ivF3 While GetOperationCount(eID)>count nWhf GetOperation eID, count, op jvpv1>KYV If op.Type="ShiftZ" Then KOoV'YSC[( DeleteOperation eID,count x:h)\%Dg< count=count-1 X$?0C{@.} End If y
qK*E* count=count+1 M.bkFuh Wend 1H-~+lf Ggy?5N7P 'Set new shift in lXEnm-_ op.Type = "ShiftZ" r]]:/pw?t op.val1 = taq HVzkS|^F op.parent = parID F{_,IQ]U AddOperation eID, op (*,R21<% Print "Set aqueous humor thickness = " & taq-0.55 F!w|5,) ^/#8 " '************************************************************************* U#<{RqY 'Radius and conic constant of anterior lens Vv+ oq5hf '************************************************************************* \tY7Ga%c eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) 4,?beA GetConic eID, entity, curv, conic @ZrNV*&< tu/4 SetConic eID, entity, 1/Rant, CCant 1QnaZhu' Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant ly6dl B\qy:nr j '************************************************************************* ",#Ug"|2 'Radius and conic constant of posterior lens F&B E+b/# '************************************************************************* W|(<z'S eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) }*O8]lG GetConic eID, entity, curv, conic O^ 5C ZI8@ 6 L\ SetConic eID, entity, 1/Rpost, CCpost ^(@]5$^Z Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost U??OiKVZ+ Ps;4 ]=c '************************************************************************* 4W<[& )7 'Lens thickness (Position of posterior lens surface) 7!)VOD8Z '************************************************************************* rq\<zx]au y,@yaM}-/K parID = FindFullName( "Geometry.Arizona Eye.Lens" ) E*kZGHA 'pO-h,{TS ' Delete any z-shift(s) ~QUN O~ count = 0 5 PP^w~n While GetOperationCount(eID)>count 1]vDM&9 GetOperation eID, count, op sGpAaGY> If op.Type="ShiftZ" Then S,f#g?V DeleteOperation eID,count q'IMt7} count=count-1 H+@?K6{h End If Cv4nl7A' count=count+1 cIK4sOTJ& Wend "?FBbJ
J aJ/|N 'Set new z-shift _a_T`fE&de op.Type = "ShiftZ" &7\fj op.val1 = tlens
'-$cvH7_ op.parent = parID ] ;HCt=I~ AddOperation eID, op 5KIhk`S Print "Set lens thickness = " & tlens @W~aoq6 2MW7nIEs '************************************************************************* n</Rd= 'Lens index of refraction fN:FD` '************************************************************************* {<#b@=G eID = FindMaterial( "Lens" ) +8"P*z, GetModelMaterial eID, mat uD[T l H\a\xCP3 mat.Nd = nlens 2^nws SetModelMaterial eID, mat N^k&
8 Print "Set lens index of refraction = " & nlens ikb77?. XN{zl* ` '************************************************************************* .CNwuN\ 'Pupil diameter W1ndb: '************************************************************************* @RL'pKab9 eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) oiD{Z C~.T[Mlu 'Adjust pupil diameter (trimming volume inner hole) Prc1U)nfo 'Z%1Ly^b SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" e-1G\}E `)MKCw$e ' Adjust pupil location to just in front of the lens I7#JT?\} parID = FindFullName( "Geometry.Arizona Eye" )
.C5JQO eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) TefPxvd count = 0 $Zkk14 While GetOperationCount(eID)>count yJ6g{#X4K< GetOperation eID, count, op LB9W.cA
If op.Type="ShiftZ" Then CC3M7|eO3 DeleteOperation eID,count iOL/u)
count=count-1 '/AX'U8Y End If ~k}O"{
y count=count+1 ^&$86-PB/ Wend rp2g./2 op.Type = "ShiftZ" \~t!M~H op.val1 = taq-0.01 hTcU
%Nc op.parent = parID Kb1@ + AddOperation eID, op ?IoA;GBg 8U4In[4 Print "Set pupil diameter = " & pupilDiam hb
%F"Q S/RChg_L5 'Update AZ Eye subassembly Description e~cg
(. eID = FindFullName( "Geometry.Arizona Eye" ) U6y`:G;. GetEntity eID, entity -(ST entity.Description = "Accommodation = " & A & "D" Kltqe5 SetEntity eID, entity u`Y~r<?P( cqW(9A|8 Update Z)@[N
6\? Print "DONE!" )|AxQPd vF>]9sMv End Sub s#")hMJQ iun_z$I<+Z 如果屈光度是4,光瞳直径是4,则会输出如下数据: 'op_GW 'fk6]&-I Accommodation = 4 Diopters $jv"$0Fc Pupil Diameter = 4 mm n[# **s Set aqueous humor thickness = 2.81 W/CZ/Mc Set anterior lens radius = 10.4 and conic constant = -2.375869 h^''ue" Set posterior lens radius = -4.424557 and conic constant = -3.081019 I:YgKs)[ Set lens thickness = 3.927 GhjqStjS&l Set lens index of refraction = 1.42672 B?y[ %i Set pupil diameter = 4 HS\'{4P DONE! vL^ +X`.td Dk8@x8
v\?l+-A?y QQ:2987619807 {LCKt/Z>P
|