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2021-10-22 09:55 |
Arizona眼睛模型
简介 hBDmC_\~ b-#oE{(\' 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。 Tkj
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:2x4 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。 I!Fd~g9I4 Gfepm$*%
Table 1. AZ眼睛模型的定义 a3[,3 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. ]~pM;6Pu0 ?%T]V+40 光源 Gg^gK*D !W b Q9o 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。 TQpR' `@&WELFv{ MdnapxuS
图1. 光源和提示信息使用 E,/nK 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。 +WCV"m _!yUr5&,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。 =s:Z-*vy! `{ \)Wuw
图2. 字母F光源的设定方法光 t&o&gb b:x~Jz#%2
图3. 字母F在视网膜上位置点列图 s +0S,?{$ 视网膜的散射 Tog'3k9Uw "!#KQ''R 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。 \5#eBJ 0J.]`kR dFk$rr>q
图4. 视网膜朗伯散射设定 DH])Q5 注意在视网膜的表面有散射重点采样规格定义,在“Scatter”标签的底部可获取该信息。“toward pupil”指定散射光朝向光瞳,半角度10度。 =_$Hn>vO ?0d#O_la3 (Wn^~-`=+
图5. 视网膜重点采样规格设定 :TP\pH 7E 脚本 QOv@rP/ G4EuW *~ 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: wYd{X 8$ (I#3![q
图6. 用户对话框的创建与编辑 %d0BQ|
图7. 用户对话框编辑器 *3(mNpi{_ 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。 we33GMxHl` 余下的脚本计算与屈光度有关的所有参数。 4=l$wg~; mfk^t`w_ 分析 gAK"ShOhG= 5?>ES* 屈光度为4,光瞳直径为4mm,字母F点在视网膜上所成的像。 (J.U{N v *$Z?Owl7
图7. 字母F在视网膜上颜色分析 &iaS3x 脚本代码 &Y2Dft_K D1wONss Option Explicit 'Remove this to enable non-dimensioned variables to be used. 55zy]|F" %vRCs] Dim entity As T_ENTITY +DYsBCVbag Dim op As T_OPERATION ~Vf
A Dim mat As T_MODELMATERIAL |0VZ1{=* Dim A As Double $AdBX}{ Dim pupilDiam As Double H
;)B5C Dim eID As Long ]}9[ys Dim parID As Long n"Wlfd0 Dim count As Integer m(^nG_eX Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double AK&=/[U> Dim tlens As Double, nlens As Double UYhxgPGsj Dim curv As Double, conic As Double 9[:TWvd Dim ok As Long ?DKY;:dZF C/q!! Sub Main sV]I]DR [G"Va_A8 '用户输入对话框 [6\b(kS+ Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 ULzrJbP'7 TextBox 220,21,40,21,.TextBox1 'default: 0 yKC1h`2 Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 G
BM8:IG \ OKButton 40,91,90,21 bv}e[yH CancelButton 190,91,90,21 vU9:`@beu Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 qTe@?j TextBox 220,49,40,21,.TextBox2 'default: 4 D=}\]Krmay End Dialog c-ql Dim dlg As UserDialog @iN"]GFjS No*[@D]g
ok = Dialog (dlg) dEZlJo@J /25Ay If ok=0 Then 'cancel button was pressed V+t's*9o3 Print "Execution cancelled." ~,.;2K73 End k +Cwnp End If _Sl3) TrBW0Bn>p 'Assign accommodation and pupil diameter & use defaults if field left empty sGc.;": If dlg.TextBox1 = "" Then ;?%_jB$P A = 0 'Default accommodation mB"1QtD Else XJ7pX1nf A = CDbl(dlg.TextBox1) (QQkXlJ End If T@a|*.V \;JZt[ If dlg.TextBox2 = "" Then S1U[{R?, pupilDiam = 4 'Default pupil diameter ,(NN)Oj Else q`UaJ_7 pupilDiam = CDbl(dlg.TextBox2) KtHkLYOCG End If N! I$Qtr, ;3o7>yEv Print " " 1:J+`mzpl Print "Accommodation = " & A & " Diopters" Rx?ze( Print "Pupil Diameter = " & pupilDiam & " mm" ER0B{b I{=Yuc ' Calculate new parameters with accommodation Zpz3?VM( taq = 0.55 + 2.97 - 0.04*A 'Aqueous thickness &^l(RBp]0 |qBcE Rant = 12.0 - 0.4*A 'Radius of anterior lens fElFyOo+ CCant = -7.518749 + 1.285720*A 'Conic constant of anterior lens nlA:C>= 'c# }^@G Rpost = -5.224557 + 0.2*A 'Radius of posterior lens bAwKmk9C CCpost = -1.353971 - 0.431762*A 'Conic constant of posterior lens iUk#hLLC AWJA? tlens = 3.767 + 0.04*A 'Lens thickness JfmYr47Pv cQm4q19 nlens = 1.42 + 0.00256*A - 0.00022*A^2 'Lens index of refraction 73Hm:"Eqd w^U{e
xo 'Adjust parameters to account for accommodation ;; ;=)'o lc3Gu78 A/ '************************************************************************* SmIcqM 'Aqueous thickness (Position of Lens) ;a| ~YM2I '************************************************************************* <y?=;54a eID = FindFullName( "Geometry.Arizona Eye.Lens" ) +wxsAGy_j GetCustomElement eID, entity GP^.h kVs Sa
kew parID = FindFullName( "Geometry.Arizona Eye" ) gtePo[ZH.P _,/~P) ' Delete any shift(s) in z [2h.5.af count = 0 9zY6hh** While GetOperationCount(eID)>count ]Y!x7 GetOperation eID, count, op (|NC xey If op.Type="ShiftZ" Then b` va\'&3 DeleteOperation eID,count eTuKu(0
E count=count-1 72 |O&`O End If [c;#>UQMf count=count+1 FRQ0t!b<M1 Wend T^(> 8/O .ws86stFSb 'Set new shift in I2Imb9k~B op.Type = "ShiftZ" EC 1|$Co op.val1 = taq aYDo0?kF' op.parent = parID @5ud{"|2 AddOperation eID, op ,[)l>!0\H Print "Set aqueous humor thickness = " & taq-0.55 M&/%qF15 Fk^N7EJ:$ '************************************************************************* 4QTHBT+2` 'Radius and conic constant of anterior lens .6xMLo,R '************************************************************************* {_/ o' 6 eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) 6uT*Fg-G GetConic eID, entity, curv, conic {/H<_ ft$RF SetConic eID, entity, 1/Rant, CCant CH&{x7$he
Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant &*%x]fQ@ uYWD.]X;[ '************************************************************************* ],k~t5+ 'Radius and conic constant of posterior lens *BdH
&U '************************************************************************* R TpNxr{[ eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) U3Z=X TB GetConic eID, entity, curv, conic QS5t~rb XbB(<\0+ SetConic eID, entity, 1/Rpost, CCpost N2"B\ Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost .7
0 a4*976~![ '************************************************************************* gXJBb+P
'Lens thickness (Position of posterior lens surface) %9a3$OGZX '************************************************************************* %^L{K[} )*>wa%[-q parID = FindFullName( "Geometry.Arizona Eye.Lens" ) XUA@f* (D) KU9B> ' Delete any z-shift(s) dC{dw^ count = 0 f?51sr While GetOperationCount(eID)>count L*tfYonq GetOperation eID, count, op U/^#nU., If op.Type="ShiftZ" Then 3ie
k>'T DeleteOperation eID,count !Yv_V]u= count=count-1 &UOxS W End If o3/o2[s count=count+1 V<J1.8H
Wend f|FS%]fCxk CV.|~K0O 'Set new z-shift oDMPYkpTu op.Type = "ShiftZ" ^`'\eEa op.val1 = tlens 8c+V$rH_ op.parent = parID }!oEjcX' AddOperation eID, op } &B6 Print "Set lens thickness = " & tlens rB$~,q&.V O5 73AA '************************************************************************* e;"J,7@ 'Lens index of refraction j<*7p:L7_> '************************************************************************* |HD>m'e eID = FindMaterial( "Lens" ) 3HpqMz GetModelMaterial eID, mat 5@m
,*n&[ LhbdvJAk@ mat.Nd = nlens ou <3}g SetModelMaterial eID, mat z R?R,k)m Print "Set lens index of refraction = " & nlens 3ai[ r _&hM6N '************************************************************************* $t):r@L 'Pupil diameter B_Q{B|eEt& '************************************************************************* V;xPZ2C; eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) =JIceLL -&>V.hi7 'Adjust pupil diameter (trimming volume inner hole) E6TeZ%g X$we\t SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" |p&EP2?T <v|"eq} ' Adjust pupil location to just in front of the lens BX0lk parID = FindFullName( "Geometry.Arizona Eye" ) vS>'LX eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) RTcxZ/\"# count = 0 Y:ly x-lj While GetOperationCount(eID)>count P\7*ql` GetOperation eID, count, op LBCH7@V1yR If op.Type="ShiftZ" Then (yqe4 DeleteOperation eID,count TjTG+uQ count=count-1 m7'<k1#"Y End If i"0Bc{cQ count=count+1 s Z[[ymu8 Wend U.Mfu9}#: op.Type = "ShiftZ" n?EgC8b9 op.val1 = taq-0.01 5;/n`Bd op.parent = parID 7z4k5d<^_ AddOperation eID, op pY"WW0p"C 51q|-d Print "Set pupil diameter = " & pupilDiam t^~vi'bB <b zzbR[F 'Update AZ Eye subassembly Description wc;n=
% eID = FindFullName( "Geometry.Arizona Eye" ) 6e+'Y"v GetEntity eID, entity #uhUZq entity.Description = "Accommodation = " & A & "D" 9;e!r DW,# SetEntity eID, entity p@^G)x XGx[Ny_A2 Update :snO*Zg Print "DONE!" (SBhU:^h aV'bI End Sub <giBL L! \~
D(ww 如果屈光度是4,光瞳直径是4,则会输出如下数据: ZZT #V%Q=u N; g@lyo Accommodation = 4 Diopters xQu|D>kv87 Pupil Diameter = 4 mm W "'6M=* Set aqueous humor thickness = 2.81 4b2d(x)0X Set anterior lens radius = 10.4 and conic constant = -2.375869 eO!9;dJ Set posterior lens radius = -4.424557 and conic constant = -3.081019 CQ!pt@|d Set lens thickness = 3.927 'I]XX==_ Set lens index of refraction = 1.42672 p\w<~pN[ Set pupil diameter = 4 =8\.fp DONE! )\akIA
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