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2022-02-25 09:52 |
Arizona眼睛模型
简介 jF{gDK H?j-=Zka 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。 9K46>_TyH C;q}3c*L 模型 npcBpGL{ .k`*$1?73x 模型的定义如表1种所示,由半径、圆锥常数、折射率、阿贝数、到下一面的距离等一系列表面组成。一些参数由屈光度(A)来决定。 Kxc$wN< Table 1. AZ眼睛模型的定义 [attachment=111140] BhW]Oq& s~Wu0%])Q 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. 1qj%a%R qTHg[sME 光源 ZBR^[OXO CS5jJi"pD3 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"`=BU& NB5L{Gf6- [attachment=111141] 图1. 光源和提示信息使用 u45h{i-e 7e4tUAiuU 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。 1mn$Rh&dO EO/cW<uV' 在往下看是内置的脚本用来修改屈光度,使其为4(250mm),光源“Letter F”在视网膜处生成一个字母为F的图像。绿色的光线聚焦的非常好而红色和蓝色光线有一点的模糊。使用Positions Spot Diagram分析工具来观察最为合适。 "1!.^<V* [attachment=111142] 图2. 字母F光源的设定方法光 .;Utkf'I i %hn [attachment=111143] 图3. 字母F在视网膜上位置点列图 ,}IER IEoR7: 视网膜的散射 |g\. 5IM#W t7oz9fSz=? 在散射文件中,有一个名为“Retina surface”的72%的反射型朗伯散射,它为视网膜的散射提供了一个粗略的近似。为了模拟来自视网膜的散射,改变自定义元件“Eye ball” 下的视网膜的表面从“halt all” 到”Allow All”。并使几何中“plane”可追迹。 k;fnC+Y$s $sc8)d\B [attachment=111144] 图4. 视网膜朗伯散射设定 O3C)N
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j+13H+dN 注意在视网膜的表面有散射重点采样规格定义,在“Scatter”标签的底部可获取该信息。“toward pupil”指定散射光朝向光瞳,半角度10度。 M,\|V3s I"Q9W|J_& [attachment=111145] 图5. 视网膜重点采样规格设定 1s}``1> t66f 7AR 脚本 I6hhU;)C !v5sWVVR 内置脚本使用对话框显示屈光度和光瞳直径的数值设置。使用FRED Basic脚本创建和使用对话框非常容易。图6显示了如何获取用户自定义对话框,如下图所示: iTugvb [attachment=111146] 图6. 用户对话框的创建与编辑 }`9fZK{. @ [attachment=111147] 图7. 用户对话框编辑器 )1Ma~8Y%r Eo {1y 如果“OK”按钮按下,将会核对对话框下面的代码行,如果点击取消则脚本终止。然后输入的参数赋予变量,如果此处是保留为空白,则使用默认值。因此,如果没有值输入并点击“OK”按钮,则脚本是以屈光度为0,光瞳直径为4mm来运行的。 Nx4DC 余下的脚本计算与屈光度有关的所有参数。 X[~f:E[1J
krr-ZiK 分析 >^T,U0T]) `z$uw
屈光度为4,光瞳直径为4mm,字母F点在视网膜上所成的像。 e1`)3-f [attachment=111148] 图7. 字母F在视网膜上颜色分析 E%k ]cZ \9>g;qPg} 脚本代码 .}$`+h8WT 4lY&=_K[)
- Option Explicit 'Remove this to enable non-dimensioned variables to be used. ^;)SFmjg%
(Y'UvZlM%P Dim entity As T_ENTITY 3)C6OF>7
Dim op As T_OPERATION SA`J.4yn Dim mat As T_MODELMATERIAL Pa+AF Dim A As Double v E3{H Dim pupilDiam As Double =p,4=wo{ Dim eID As Long DV7<n&P Dim parID As Long yRq8;@YGY Dim count As Integer L_
Xn, Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double 4uO
@`0:x Dim tlens As Double, nlens As Double oz\{9Lwc Dim curv As Double, conic As Double EbBv}9g Dim ok As Long g/U$!d_ Lem\UD$D` Sub Main =#.8$oa^ f
gK2.;> '用户输入对话框 8g#
c%eZ Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 P;L)1 g TextBox 220,21,40,21,.TextBox1 'default: 0 +Dq|l} Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 YoV^xl6g OKButton 40,91,90,21 ?b*/ddIs CancelButton 190,91,90,21 w
L/p.@ Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 ,`%k'ecN TextBox 220,49,40,21,.TextBox2 'default: 4 D% v:PYf End Dialog =A0"0D{\ Dim dlg As UserDialog 9&[)(On74 |z!q
r}i ok = Dialog (dlg)
8(vC jL 3ZW/$KP/ If ok=0 Then 'cancel button was pressed ] 689 Q%D Print "Execution cancelled." j{Yt70Wv End `zElBD End If :c~9>GCE& Z%Tq1O 'Assign accommodation and pupil diameter & use defaults if field left empty z`86-Ov If dlg.TextBox1 = "" Then q7O,I`KaJ A = 0 'Default accommodation ==-7F3QP Else ;e#>n!<u A = CDbl(dlg.TextBox1) xE G+%Uk{ End If 3i]"#wK ~h>rskJ_ If dlg.TextBox2 = "" Then RMS.1: O
pupilDiam = 4 'Default pupil diameter 2cs?("8e% Else 'WKu0Yi^' pupilDiam = CDbl(dlg.TextBox2) 2|0Je^$| End If ;-3h ~k p<of<YU) Print " " AI^AK0.L Print "Accommodation = " & A & " Diopters" q;~R:}?@ Print "Pupil Diameter = " & pupilDiam & " mm" (ZE%tbm2 T8,k77 ' Calculate new parameters with accommodation ]6a/0rg:t taq = 0.55 + 2.97 - 0.04*A 'Aqueous thickness E<D+)A &K9VEMCEX Rant = 12.0 - 0.4*A 'Radius of anterior lens *ajFZI CCant = -7.518749 + 1.285720*A 'Conic constant of anterior lens [ E$$nNs ^Ei*M0fF Rpost = -5.224557 + 0.2*A 'Radius of posterior lens o
:.~X CCpost = -1.353971 - 0.431762*A 'Conic constant of posterior lens VRtbHam ppwd-^f3j tlens = 3.767 + 0.04*A 'Lens thickness 2k.S[?) D 7Gd% nlens = 1.42 + 0.00256*A - 0.00022*A^2 'Lens index of refraction ?Ia4H lEO?kn.:z 'Adjust parameters to account for accommodation r\A@&5#q Du)B9s '************************************************************************* 7j@^+rkr3f 'Aqueous thickness (Position of Lens) q6;OS.f '************************************************************************* 9>A-$a4R> eID = FindFullName( "Geometry.Arizona Eye.Lens" ) &GXtdO>;Zv GetCustomElement eID, entity t!6\7Vm/ C!$Xv&"r parID = FindFullName( "Geometry.Arizona Eye" ) GIl:3iB49 JiKImz ' Delete any shift(s) in z z{_mEE49 count = 0 QDIsC While GetOperationCount(eID)>count /- DKV~ GetOperation eID, count, op O"@?U If op.Type="ShiftZ" Then #Y;.>mF DeleteOperation eID,count ,DE(5iDS count=count-1 TZ^{pvBy End If 1P5*wNF count=count+1 i
FC"!23f Wend {@Blj3 ;w} .[edln 'Set new shift in $@_YdZ! op.Type = "ShiftZ" ! a86iHU op.val1 = taq l9]o\JFXk op.parent = parID y.jS{r". AddOperation eID, op 5\uNEs$T Print "Set aqueous humor thickness = " & taq-0.55 4qqF v?O[r ^bF}_CSE '************************************************************************* 5?^]1P_ 'Radius and conic constant of anterior lens ?2H{^\<(e '************************************************************************* {]+ jL1 eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) 60~v
t04 GetConic eID, entity, curv, conic Xyb8u})p' @[n2dmj SetConic eID, entity, 1/Rant, CCant !.9l4@z# Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant (&q@~
dJ FL59 '************************************************************************* 4;?1Kb# 'Radius and conic constant of posterior lens 6!*K/2:O '************************************************************************* ERk kSTp eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) #]"/{Z GetConic eID, entity, curv, conic #1MKEfv(~ #g,H("Qy({ SetConic eID, entity, 1/Rpost, CCpost x<8\- Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost X>2?
`8M "_t4F4z '************************************************************************* &Y 'z?N 'Lens thickness (Position of posterior lens surface) HS7R lU^ '************************************************************************* L+_8QK < r~I.F!{ parID = FindFullName( "Geometry.Arizona Eye.Lens" ) b7Yq_%+ ldP3n:7FS ' Delete any z-shift(s) t/ A:k count = 0 QI.t&sCh5 While GetOperationCount(eID)>count eDuX"/kHA GetOperation eID, count, op GM:,CJ? If op.Type="ShiftZ" Then 9 _eS`,' DeleteOperation eID,count v<j2L"bj count=count-1 )#C_mB$-# End If O!o <P5X^ count=count+1 sb'lZFSP~s Wend -H4PRCDH ^<!Ia 'Set new z-shift X@cSP7b op.Type = "ShiftZ" fTTm$,f5N op.val1 = tlens vXc!Zg~ op.parent = parID {798=pC<. AddOperation eID, op 4yhcK& Print "Set lens thickness = " & tlens [@g ~ Xp#~N_S$ '************************************************************************* [
ynuj3G
V 'Lens index of refraction '\@WN]
'************************************************************************* hRk,vB] eID = FindMaterial( "Lens" ) So?m?,!W GetModelMaterial eID, mat y!F:m=x< 3zbXAR* mat.Nd = nlens TWtC-wI; SetModelMaterial eID, mat -E:(w<]; Print "Set lens index of refraction = " & nlens #o~[1K+Yq aJa.U^1{ '************************************************************************* D6Dn&/>Zp 'Pupil diameter ekrBNDs9 '************************************************************************* %
^e@`0L eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) O6/xPeak J, r Xx: 'Adjust pupil diameter (trimming volume inner hole) ]/a
g*F }H5/3be SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" TKd6MZhT _nP)uU$ ' Adjust pupil location to just in front of the lens `6UtxJSx parID = FindFullName( "Geometry.Arizona Eye" ) ,^HS`!s[ E eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) 9Kx<\)-GMD count = 0 @bE~@4mOu While GetOperationCount(eID)>count $ND90my GetOperation eID, count, op b1H7 If op.Type="ShiftZ" Then gXF.on4B DeleteOperation eID,count uQWp+}>ZJy count=count-1 %iX/y End If (xbIUz. count=count+1 QsM*wT&aa Wend 'P,,<nkr| op.Type = "ShiftZ" Jb9F=s+ op.val1 = taq-0.01 \x(.d.l/ op.parent = parID K|Om5
p AddOperation eID, op ]r!QmWw~V g[AA,@p+ Print "Set pupil diameter = " & pupilDiam zPHy2H$28
">cqt>2 A 'Update AZ Eye subassembly Description T30Zk*V eID = FindFullName( "Geometry.Arizona Eye" ) ldYeX+J
_ GetEntity eID, entity g9`[Y~ entity.Description = "Accommodation = " & A & "D" "U*5Z:8?9 SetEntity eID, entity B 2Qp} @"w2R$o Update FZH-q!"^cK Print "DONE!" BD4`eiu" V!W1fb7V End Sub rtus`A5p _=?2 3 如果屈光度是4,光瞳直径是4,则会输出如下数据: }f]b't Ox~ 9_d Accommodation = 4 Diopters `/0u{[
Pupil Diameter = 4 mm }s(C^0x Set aqueous humor thickness = 2.81 rpSr^slr Set anterior lens radius = 10.4 and conic constant = -2.375869 "9%qbMB Set posterior lens radius = -4.424557 and conic constant = -3.081019 %EWq2'/5 Set lens thickness = 3.927 }I]W'<jY Set lens index of refraction = 1.42672 =!<^^6LZ Set pupil diameter = 4 :6zC4Sr^ DONE!
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