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2022-02-25 09:52 |
Arizona眼睛模型
简介 62/tg*) !f8]gT zN 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。 t$U eks =Xb:. 模型 N*>&XJ# p{rzP,Pb& 模型的定义如表1种所示,由半径、圆锥常数、折射率、阿贝数、到下一面的距离等一系列表面组成。一些参数由屈光度(A)来决定。 DGx<Nys@B Table 1. AZ眼睛模型的定义 [attachment=111140] x*F_XE1#M GG`;c?d@ 在FRED中使用0屈光度来创建的,光瞳加在了透镜的前面。材料是创建一个新的材料并选择类型“Model Material”,输入的参数是nd和vd. D??
\H\ d7L|yeb" 光源 +}!FP3KgT
C6}`qD 多个光源定义来分析该模型的不同特性。图1显示了所以的光源和提示信息告诉您他们可以用来做什么。 5%XEybc2 Cv1CRmqq% [attachment=111141] 图1. 光源和提示信息使用 JuXuS NE!] 除了“Letter F”之外的所有光源的光线位置设定在了孔径光阑位置处,并增加了pre-propagation distance= -8。尽管光线在光瞳处创建,规定的传输方向相对于光线位置在pre-propagation distance之后。这意味着光束沿着Z轴在眼睛的前面以平行光入射,而不是在光瞳处入射。 SV_b(wP9 tumYZ)nW 在往下看是内置的脚本用来修改屈光度,使其为4(250mm),光源“Letter F”在视网膜处生成一个字母为F的图像。绿色的光线聚焦的非常好而红色和蓝色光线有一点的模糊。使用Positions Spot Diagram分析工具来观察最为合适。 7
[?]DyOf [attachment=111142] 图2. 字母F光源的设定方法光 5!^?H"#c Vb8{OD3PK [attachment=111143] 图3. 字母F在视网膜上位置点列图 qu0dWgK uF\f>E)/N% 视网膜的散射 ln=:E$jX {DGnh1 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。 {FNq&)#` U~[ tp1Z) [attachment=111144] 图4. 视网膜朗伯散射设定 /hbdQm "Bbd[ZI8 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。 wg 6 &+F}$8, [attachment=111145] 图5. 视网膜重点采样规格设定 u1i
?L' &$E.rgtg 脚本 .ID9Xd$fky 1
gx(L*y, 内置脚本使用对话框显示屈光度和光瞳直径的数值设置。使用FRED Basic脚本创建和使用对话框非常容易。图6显示了如何获取用户自定义对话框,如下图所示: 8AVG pL [attachment=111146] 图6. 用户对话框的创建与编辑 7e`h,e= [attachment=111147] 图7. 用户对话框编辑器 _'DZoOH|VE Hqm1[G) 如果“OK”按钮按下,将会核对对话框下面的代码行,如果点击取消则脚本终止。然后输入的参数赋予变量,如果此处是保留为空白,则使用默认值。因此,如果没有值输入并点击“OK”按钮,则脚本是以屈光度为0,光瞳直径为4mm来运行的。 Fo[=Dh*AqU 余下的脚本计算与屈光度有关的所有参数。 sD`OHV: [^E{Yz=8, 分析 @)p?!3{" &IgH]?t 屈光度为4,光瞳直径为4mm,字母F点在视网膜上所成的像。 Nc[V kJ] [attachment=111148] 图7. 字母F在视网膜上颜色分析 #`{L_n$c b R;Wf5 脚本代码 ;tu2}1#r w?zY9Fs=s
- Option Explicit 'Remove this to enable non-dimensioned variables to be used. ?513A>U
/ :@X< Dim entity As T_ENTITY R?GF,s<j Dim op As T_OPERATION jneos~ 'n8 Dim mat As T_MODELMATERIAL i5^U1K\M Dim A As Double j*}2AI Dim pupilDiam As Double dsUY[X-<6 Dim eID As Long Qp]-4%^Vz Dim parID As Long '2.11cM3 Dim count As Integer 2
VGGSLr Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double 1*J#:|({(
Dim tlens As Double, nlens As Double gdfG3d$4 Dim curv As Double, conic As Double /C)FS?=
Dim ok As Long i7(\i2_P &24z`ZS[w6 Sub Main
)!(etB=`y Q.Ljz
Z '用户输入对话框 O:3DIT1#> Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 esVZ2_eL TextBox 220,21,40,21,.TextBox1 'default: 0 -6u#:pVpU Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 <FFaaGiE> OKButton 40,91,90,21 ]w[T_4l CancelButton 190,91,90,21 GcYT<pwN6 Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 y?s8UEC TextBox 220,49,40,21,.TextBox2 'default: 4 C2 ] x End Dialog eEG]JH Dim dlg As UserDialog 6C|]Fm *=ymK* ok = Dialog (dlg) %/x%hs;d Bpw<{U If ok=0 Then 'cancel button was pressed "G`8>1tO_ Print "Execution cancelled." +B0G[k7 End edy6WzxBcm End If \v}3j^Yu Z'I0e9Jw 'Assign accommodation and pupil diameter & use defaults if field left empty az2CFd^M If dlg.TextBox1 = "" Then {Qla4U A = 0 'Default accommodation a\PvRW*I Else t846:Z%[ A = CDbl(dlg.TextBox1) @0>3)) End If +2+wNFU )bGd++2 If dlg.TextBox2 = "" Then |ozlaj pupilDiam = 4 'Default pupil diameter Z/ypWoV( Else ].eY]o}= pupilDiam = CDbl(dlg.TextBox2) Xqac$%[3 End If `b{.K, ?) ~j>1"S Print " " GCgpe(cQ Print "Accommodation = " & A & " Diopters" dn1Tu6f;| Print "Pupil Diameter = " & pupilDiam & " mm" %aszZP An%V>a-[ ' Calculate new parameters with accommodation @Sl!p) taq = 0.55 + 2.97 - 0.04*A 'Aqueous thickness 5E+k}S]M$ S-Y(Vn4 Rant = 12.0 - 0.4*A 'Radius of anterior lens *I}_B\kY CCant = -7.518749 + 1.285720*A 'Conic constant of anterior lens F& 'HZX $Di2BA4Di Rpost = -5.224557 + 0.2*A 'Radius of posterior lens RO"*&o'K' CCpost = -1.353971 - 0.431762*A 'Conic constant of posterior lens 69v[*InSd plY`lqm tlens = 3.767 + 0.04*A 'Lens thickness Ht'jm ( ",ic"
~ nlens = 1.42 + 0.00256*A - 0.00022*A^2 'Lens index of refraction FDAREE\j _z!0ab 'Adjust parameters to account for accommodation JqdNO:8 E5%ae (M^ '************************************************************************* L^`oJ9k! 'Aqueous thickness (Position of Lens) adJoT-8P6 '************************************************************************* D^Z~>D6 eID = FindFullName( "Geometry.Arizona Eye.Lens" ) e<p_u)m GetCustomElement eID, entity 2Z-BZu K6p lE54RX}e4 parID = FindFullName( "Geometry.Arizona Eye" ) `f^`i~c\ Wb4%=2Qn ' Delete any shift(s) in z [^gSWU count = 0 pr-{/6j6 While GetOperationCount(eID)>count 7<=7RPWmD GetOperation eID, count, op wBcDL/(> If op.Type="ShiftZ" Then tc{23Rf% DeleteOperation eID,count g"3h#SMb count=count-1 /Ki :6 End If ~X;(m<f2 count=count+1 Kg@9kJB Wend TBQ`:`g^m u%O^hcfb 'Set new shift in tE{7S/?h op.Type = "ShiftZ" q\[31$i$ op.val1 = taq is}Fy>9i op.parent = parID MjU>qx:: AddOperation eID, op uF T\a= Print "Set aqueous humor thickness = " & taq-0.55 ^;YD3EZw 'q[V*4g '************************************************************************* T^GdN_qF 'Radius and conic constant of anterior lens >t8eVMMa '************************************************************************* e7L;{+XI eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) q9Y0Lk GetConic eID, entity, curv, conic nWZrB s
_ d1j v>tu SetConic eID, entity, 1/Rant, CCant 6x@-<{L Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant aG|)k, N13 <!QQ '************************************************************************* B0Z~L){i 'Radius and conic constant of posterior lens q@(N 38D '************************************************************************* I{cn ,,8 eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) ==(M
vu` GetConic eID, entity, curv, conic ;T52aX ]Ly)%a32 SetConic eID, entity, 1/Rpost, CCpost o7 !@WOeZ3 Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost +N4h
Q" :OI!YR%" '************************************************************************* v;K\#uc_ 'Lens thickness (Position of posterior lens surface) sCb?TyN'n '************************************************************************* `%ymg8^ 0t4i'?? parID = FindFullName( "Geometry.Arizona Eye.Lens" ) n?
s4"N6 f\(K ou$ ' Delete any z-shift(s) \iVYhl count = 0 m@c2'*&Y While GetOperationCount(eID)>count `ZefSmb GetOperation eID, count, op <1jiU%!w If op.Type="ShiftZ" Then 9J]LV'f7 DeleteOperation eID,count Pq4sv`q)S count=count-1 gieX`} End If {{DW P-v4 count=count+1 sox90o 7 Wend %)aDh
}
U3U eTa_ 'Set new z-shift V
u!,tpa. op.Type = "ShiftZ" 2=3iA09px op.val1 = tlens !E7/:t4 op.parent = parID |R[m&uOib AddOperation eID, op zu|pL`X Print "Set lens thickness = " & tlens 3S5QqAm vOP[ND=T '************************************************************************* etDB|(,z 'Lens index of refraction q{_buTARq '************************************************************************* 3> fuH'= eID = FindMaterial( "Lens" ) h'jnc. GetModelMaterial eID, mat /n_HUY gh
0\9;h mat.Nd = nlens L |H{;r' SetModelMaterial eID, mat (?3(=+t Print "Set lens index of refraction = " & nlens [wOO)FjT ?QMs< '************************************************************************* ! 9N%=6\ 'Pupil diameter $i`YtV '************************************************************************* G37_
`C eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) WMC6dD_6e ~|!lC}!IKL 'Adjust pupil diameter (trimming volume inner hole) -FPl",f=r `150$*K&B SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" ~gAx a[JgR /E@x ' Adjust pupil location to just in front of the lens # \M<6n{ parID = FindFullName( "Geometry.Arizona Eye" ) /;>EyWW eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) 4@Qq5kpk* count = 0
~.Gk:M While GetOperationCount(eID)>count P"#^i<ut@T GetOperation eID, count, op >pYgF=J If op.Type="ShiftZ" Then a&<<X:$Hy DeleteOperation eID,count `<Ftn count=count-1 NdZ:
7 End If &vn9l#\( count=count+1 = G_6D Wend aD:+,MZ op.Type = "ShiftZ" XU54skN op.val1 = taq-0.01 R3<+z op.parent = parID $pKS['J0 AddOperation eID, op .6hH}BM ^m7PXY Print "Set pupil diameter = " & pupilDiam )Qc$UI8L ?\yo~=N^ 'Update AZ Eye subassembly Description x{- caOH eID = FindFullName( "Geometry.Arizona Eye" ) nk{1z\D{ GetEntity eID, entity BCj&z{5"7e entity.Description = "Accommodation = " & A & "D" (1o^Dn3 SetEntity eID, entity A4^+p0@ Q9' p2@Z Update ~:@H6Ke[ Print "DONE!" izxCbbg :8ZxO wwv End Sub ev3x*}d0 +EB## 如果屈光度是4,光瞳直径是4,则会输出如下数据: 8+u8piG j0GI[# Accommodation = 4 Diopters `4=b|N+b" Pupil Diameter = 4 mm a !IH-XJ2 Set aqueous humor thickness = 2.81 2*M*<p=v Set anterior lens radius = 10.4 and conic constant = -2.375869 A"'MRYT` Set posterior lens radius = -4.424557 and conic constant = -3.081019 i_MI!o Set lens thickness = 3.927 A>?fbY2n Set lens index of refraction = 1.42672 (pmo[2kg Set pupil diameter = 4 cNVdGY%& DONE!
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