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2022-02-25 09:52 |
Arizona眼睛模型
简介 ^91sl5c8yD WYwzo V- 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。 X2\E9hJg *CeQY M 模型 s?^,iQ+tp 1Q&cVxA"\ 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。 0 W~.WkD Table 1. AZ眼睛模型的定义 [attachment=111140] [as-3&5S _YH<YOrMh 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. -l-AToO4 M8 iEVJ 光源 bbd0ocva j7@!J7S 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。 A$7Eo`Of ElQJ\% [attachment=111141] 图1. 光源和提示信息使用 qs!>tw #04{(G|~+E 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。 Q&u>7_, Du '1CD-
Bu 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。 z@!^ow)`J [attachment=111142] 图2. 字母F光源的设定方法光 M'\pkzx Rr+qgt;f5 [attachment=111143] 图3. 字母F在视网膜上位置点列图 ,3:QB_ KU+( YF$1 视网膜的散射 } c{Fa& Z,0O/RFJ.q 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。 HG3.~ 6X U:qF/%w [attachment=111144] 图4. 视网膜朗伯散射设定 T|;^.TZ shM{Y9~O9& 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。 $!a?i@ M$,Jg5Dc [attachment=111145] 图5. 视网膜重点采样规格设定 (JevHdI*V 'To<T 脚本 8dc538:q} pz$_W 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: Lb!r(o>8Cb [attachment=111146] 图6. 用户对话框的创建与编辑 e@[9C(5E" [attachment=111147] 图7. 用户对话框编辑器 "VV914*z xC)7eQn/R 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。 (F_w>w.h 余下的脚本计算与屈光度有关的所有参数。 6yN"
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Q7 R @"`~#$$ 分析 !loO%3_) D2Y&[zgv 屈光度为4,光瞳直径为4mm,字母F点在视网膜上所成的像。 AvZXRN1:' [attachment=111148] 图7. 字母F在视网膜上颜色分析 wjuGq.qIu
y0;,dv] 脚本代码 DX|uHbGg
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- Option Explicit 'Remove this to enable non-dimensioned variables to be used. #De(*&y2
3KtAK9PT Dim entity As T_ENTITY CP +4k.)*O Dim op As T_OPERATION 9KXym } Dim mat As T_MODELMATERIAL 9 >%+bA( Dim A As Double 1sD~7KPg? Dim pupilDiam As Double Pfm*<,'x"[ Dim eID As Long rWJ*e Y Dim parID As Long p[u4, Dim count As Integer _ ~|Q4AJ Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double $;y1Qiel Dim tlens As Double, nlens As Double 6?O}Q7G Dim curv As Double, conic As Double C}9Kx }q Dim ok As Long Q]/B/ ^ZR8s^X Sub Main rmoJ
=.' {ZG:M}ieN '用户输入对话框 cu<y8
:U< Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 M=W
4:H,gx TextBox 220,21,40,21,.TextBox1 'default: 0 L/)B}8m\ Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 ^L ]B5,}- OKButton 40,91,90,21 Y hS{$Z CancelButton 190,91,90,21 +uELTHH= Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 xLZ bU4 TextBox 220,49,40,21,.TextBox2 'default: 4 |!oXvXU End Dialog )Xp Vu Dim dlg As UserDialog ;t|,nz4kJ 5.dl>, ok = Dialog (dlg) V7BsE w +ZX.1[O If ok=0 Then 'cancel button was pressed RYH)AS4w' Print "Execution cancelled." bGu([VB End bTiBmS End If >{b3>s~T y=#j`MH{> 'Assign accommodation and pupil diameter & use defaults if field left empty $.9 +{mz If dlg.TextBox1 = "" Then %uua_) A = 0 'Default accommodation hD*(AJ Else ).Q[!lly A = CDbl(dlg.TextBox1) *.o"ZVl End If pUGN!3 $D}"k!H If dlg.TextBox2 = "" Then rfc|`*m}0 pupilDiam = 4 'Default pupil diameter 1 )'Iu`k/ Else Z B$NVY pupilDiam = CDbl(dlg.TextBox2) Gp8psH End If nn'Af,ko/ c`ftd>] Print " " js
-2"I Print "Accommodation = " & A & " Diopters" 94y9W# Print "Pupil Diameter = " & pupilDiam & " mm" fq=:h\\G q=+wI"[ ' Calculate new parameters with accommodation B2Z0 taq = 0.55 + 2.97 - 0.04*A 'Aqueous thickness 6m@0;Ht ]q&tQJ/Fa Rant = 12.0 - 0.4*A 'Radius of anterior lens :Pf>Z? /d CCant = -7.518749 + 1.285720*A 'Conic constant of anterior lens hVkO%]? djfU:$!j& Rpost = -5.224557 + 0.2*A 'Radius of posterior lens #n#HzbT CCpost = -1.353971 - 0.431762*A 'Conic constant of posterior lens AX K95eS cl_TF[n? tlens = 3.767 + 0.04*A 'Lens thickness 5x2L(l-2 Fo(y7$33* nlens = 1.42 + 0.00256*A - 0.00022*A^2 'Lens index of refraction DL1
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wmw2 'Adjust parameters to account for accommodation HD H ;t!9]1 '************************************************************************* ki#bPgT 'Aqueous thickness (Position of Lens) :]-$dEu& '************************************************************************* .lr5!Stb eID = FindFullName( "Geometry.Arizona Eye.Lens" ) T0Q51Q GetCustomElement eID, entity c;^A)_/ B$j' /e-Zk parID = FindFullName( "Geometry.Arizona Eye" ) 5VZjDg? )(]Envb?A0 ' Delete any shift(s) in z #2N_/J(U count = 0 #
M>wH`Q# While GetOperationCount(eID)>count %{"dP%|w4} GetOperation eID, count, op r>O|L%xpv If op.Type="ShiftZ" Then >4c` UW DeleteOperation eID,count tpGCrn2w> count=count-1 ]=Pu\eE End If wV>c" J count=count+1 kV+ R5R Wend -K^41W71 t#~XLCE 'Set new shift in |T
y=7d , op.Type = "ShiftZ" =Epq%,4nG op.val1 = taq d' OGVN op.parent = parID _A3X6 AddOperation eID, op QF&6?e06p0 Print "Set aqueous humor thickness = " & taq-0.55 x,uBJ abSq2*5K '************************************************************************* Tyd
h9I 'Radius and conic constant of anterior lens -N4z-ozhC '************************************************************************* ]x_F{&6U8 eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) uJ8x GetConic eID, entity, curv, conic bw5T2wYZ )qd={ SetConic eID, entity, 1/Rant, CCant 37jQ'O
U Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant _D
JCsK| cm,4&x6 '************************************************************************* R{`gR"* 'Radius and conic constant of posterior lens D )gD< '************************************************************************* lRH0)5` eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" )
p[ Hr39o GetConic eID, entity, curv, conic /ao<A\KR AK;^9b-}q: SetConic eID, entity, 1/Rpost, CCpost CW;m Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost qRl/Sl#F j%WY ,2P '************************************************************************* UFf,+4q 'Lens thickness (Position of posterior lens surface) > Y]_K '************************************************************************* --A&TV [S) G$JW parID = FindFullName( "Geometry.Arizona Eye.Lens" ) kC31$jMC3! 8t=3 ' Delete any z-shift(s) x{?sn count = 0 N6q5`Ry While GetOperationCount(eID)>count j/'
g$ GetOperation eID, count, op uQ^hV%|" If op.Type="ShiftZ" Then ThiN9! Y DeleteOperation eID,count 4|=vxJ count=count-1 BjvdnbJg End If XR+rT count=count+1 "/!'9na{QL Wend 03F3q4" y+RRg[6| 'Set new z-shift 506V0]`/ op.Type = "ShiftZ" ,(;5%+#n op.val1 = tlens 1OP"5f op.parent = parID dk8y>uLr_ AddOperation eID, op DyIV/ Print "Set lens thickness = " & tlens L20rv:W$h AA2ui% '************************************************************************* Z'e\_C 'Lens index of refraction %Co
b(C&} '************************************************************************* qw2)v*Fn eID = FindMaterial( "Lens" ) |@ *3^' GetModelMaterial eID, mat zhjJ>d%w 0mVuD\#=! mat.Nd = nlens -[Y:?lA SetModelMaterial eID, mat bOe<\Y$ Print "Set lens index of refraction = " & nlens nd;O(s; P8IRH#ED '************************************************************************* gW}} 5Xq 'Pupil diameter ?Nu#]u- '************************************************************************* KX=/B=3~ eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) #<UuI9 R}hlDJ/m- 'Adjust pupil diameter (trimming volume inner hole) d=F)y~&' GZS{&w! SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" jzQ I>u ;M-,HK4= ' Adjust pupil location to just in front of the lens umryA{Ps parID = FindFullName( "Geometry.Arizona Eye" ) Hva{A
# eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) 4rm87/u*0 count = 0 ,[^o9u uB While GetOperationCount(eID)>count aX]y` GetOperation eID, count, op s<,"Hsh^CR If op.Type="ShiftZ" Then [?|5oaK DeleteOperation eID,count =/m}rcDN count=count-1 -CwWs~! End If }FZp840 count=count+1 =@%MV( Wend 0OEtU5lf`y op.Type = "ShiftZ" ;2BPPZ op.val1 = taq-0.01 \wTW?>oZ op.parent = parID 0$!.c~ AddOperation eID, op 9 #:ue@) X!m;uJZp Print "Set pupil diameter = " & pupilDiam w2'
3S#nZ vRxL&8`& 'Update AZ Eye subassembly Description aK-N}T eID = FindFullName( "Geometry.Arizona Eye" ) 9z5z GetEntity eID, entity
nMeS CX entity.Description = "Accommodation = " & A & "D" ,znL,%s SetEntity eID, entity g*^wF?t'T :%pw`b, =V Update 7@3M]5:3g Print "DONE!" xR _DY'z E|\3f(aF End Sub WGluZhRuT3 5t TLMZ `o 如果屈光度是4,光瞳直径是4,则会输出如下数据: ]D?oQ$q7 cz$c)It Accommodation = 4 Diopters ;wfH^2HxE) Pupil Diameter = 4 mm Fv<]mu Set aqueous humor thickness = 2.81 ud5x$` Set anterior lens radius = 10.4 and conic constant = -2.375869 !P+~c0DF Set posterior lens radius = -4.424557 and conic constant = -3.081019 0GF%~6 Set lens thickness = 3.927 +38Lojb} Set lens index of refraction = 1.42672 CRP7U Set pupil diameter = 4 zv>ZrFl* DONE!
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