[分享]Arizona眼睛模型 [复制链接]

简介 C|pdv  
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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。 9mA{K   
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模型 3k#~yaoI  
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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。 X 1 57$  
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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. 9IX/wm"  
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光源 }zhGS!fO  
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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。 KQB
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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。 |*}4 m'c  
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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。 }Y;K~J  
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视网膜的散射 (1#J%  
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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。 l1f\=G?tmU  
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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。 
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脚本 ,^C--tgZJg  
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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： >r!|sC  
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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。 \SBc;  
余下的脚本计算与屈光度有关的所有参数。 INJEsz  
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分析 MRdduPrM%$  
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屈光度为4，光瞳直径为4mm，字母F点在视网膜上所成的像。 @0/+_2MH-  
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脚本代码 'h,VR=e<  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. c}2jmwq  
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Dim entity As T_ENTITY ivN&HAxI@  
Dim op As T_OPERATION t:'Mh9h7u  
Dim mat As T_MODELMATERIAL C$XU%5qi  
Dim A As Double sM `DL  
Dim pupilDiam As Double ;EP:
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Dim eID As Long u)+8S/ )  
Dim parID As Long NgP&.39U  
Dim count As Integer 7_inJ$  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double A;]}m8(*  
Dim tlens As Double, nlens As Double vVFy*#I#_[  
Dim curv As Double, conic As Double U_I5fK=  
Dim ok As Long |xdsl,  
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Sub Main K3#@SYj  
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    '用户输入对话框 b?tB(if!I  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1
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        TextBox 220,21,40,21,.TextBox1 'default: 0 7%x[q}  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 /}b03  
        OKButton 40,91,90,21 GLeK'0Q@  
        CancelButton 190,91,90,21 Bf~vA4  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 r{L> F]Tw  
        TextBox 220,49,40,21,.TextBox2 'default: 4 U@uGNMKR  
    End Dialog 0dE@c./R i  
    Dim dlg As UserDialog S.-TOE  
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    ok = Dialog (dlg) -"'j7t:  
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    If ok=0 Then    'cancel button was pressed 'h|DO/X~L  
        Print "Execution cancelled." 128EPK  
        End KBx6NU?;PO  
    End If ~j}cyHg  
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    'Assign accommodation and pupil diameter & use defaults if field left empty [+n*~
  
    If dlg.TextBox1 = "" Then keL&b/@  
        A = 0           'Default accommodation v$?+MNks  
    Else mwHB(7YS,  
        A = CDbl(dlg.TextBox1) jaII r06  
    End If PNgY>=Y  
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    If dlg.TextBox2 = "" Then :LF?  
        pupilDiam = 4   'Default pupil diameter Yg%I?  
    Else 1ySk;;3  
        pupilDiam = CDbl(dlg.TextBox2) Vc&!OE  
    End If ?PeJlp
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    Print " " E7j(QOf  
    Print "Accommodation = " & A & " Diopters" [9evz}X  
    Print "Pupil Diameter = " & pupilDiam & " mm" PUp6Q;AdQ  
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    ' Calculate new parameters with accommodation 1"MhGNynB>  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness [1g8*j~L  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens Y!-M_v/  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens ;=)k<6  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens #+ 0M2Sa  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens Lb:g4A"  
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    tlens = 3.767 + 0.04*A                  'Lens thickness ,w<S|#W~+  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction ;DqWh0  
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    'Adjust parameters to account for accommodation AVlhNIr  
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    '************************************************************************* I8
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    'Aqueous thickness (Position of Lens) q;T{|5/O  
    '************************************************************************* <'y?KiphL  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) 5d Eh7XL  
    GetCustomElement eID, entity 2b}t,&bv?  
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    parID = FindFullName( "Geometry.Arizona Eye" ) deBY5|  
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    ' Delete any shift(s) in z n4;.W#\  
    count = 0 =upeRY@u5  
    While GetOperationCount(eID)>count k9sh @ENy  
        GetOperation eID, count, op kJ'
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        If op.Type="ShiftZ" Then '\l"   
            DeleteOperation eID,count >*~L28Fyn  
            count=count-1 SD"FErJ  
        End If ?8npG]L)  
        count=count+1 dI.WK@W'o  
    Wend jl4rbzse  
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    'Set new shift in &
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    op.Type = "ShiftZ" 9vuyv*-}e  
    op.val1 = taq fiK6@,  
    op.parent = parID ,k +IPkN+  
    AddOperation eID, op hci6P>h<ia  
    Print "Set aqueous humor thickness = " & taq-0.55 ?AK(|  
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    '************************************************************************* b z`+k,*  
    'Radius and conic constant of anterior lens 7Haa;2 T'  
    '************************************************************************* I:R[;TB?y  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) -]0OKE&  
    GetConic eID, entity, curv, conic Ci@o|Y }tP  
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    SetConic eID, entity, 1/Rant, CCant  Uf:`  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant {fPy=,>Nb  
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    '************************************************************************* x,=&JtKVc  
    'Radius and conic constant of posterior lens so,t  
    '************************************************************************* F&!6jv  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) ~8q)^vm>f?  
    GetConic eID, entity, curv, conic %0S3V[4I  
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    SetConic eID, entity, 1/Rpost, CCpost tqz3zIQ  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost ]J1dt
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    '************************************************************************* [g7L&`f9  
    'Lens thickness (Position of posterior lens surface) ]~Rho_mq#  
    '************************************************************************* pR*VdC _mY  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) lEH
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    ' Delete any z-shift(s) Xpr?Kgz  
    count = 0 XQY#716)  
    While GetOperationCount(eID)>count QmQ=q7  
        GetOperation eID, count, op A!od9W6  
        If op.Type="ShiftZ" Then
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            DeleteOperation eID,count 8H%;WU9-  
            count=count-1 p)KheLiZ  
        End If D#_3^Kiawj  
        count=count+1 D>`xzt'.6  
    Wend y*4=c_Z  
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    'Set new z-shift !S$:*5=&  
    op.Type = "ShiftZ" NxkGOAOE  
    op.val1 = tlens bg!/%[ {M  
    op.parent = parID ahJ`T*)
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    AddOperation eID, op M,j U}yD3  
    Print "Set lens thickness = " & tlens prWk2_D;*  
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    '************************************************************************* 6|gCuT4  
    'Lens index of refraction )MtF23k)g  
    '************************************************************************* 8EZ$g<}  
    eID = FindMaterial( "Lens" ) x) ,eI'mf  
    GetModelMaterial eID, mat 57'*
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    mat.Nd = nlens Q
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    SetModelMaterial eID, mat ` )/vq-9  
    Print "Set lens index of refraction = " & nlens ~k"=4j9  
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    '************************************************************************* aHV;N#Lx3  
    'Pupil diameter ?k+xSV  
    '************************************************************************* >Rl"  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) Jz\%%C  
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    'Adjust pupil diameter (trimming volume inner hole) -"R2  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" 6]&OrS[  
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    ' Adjust pupil location to just in front of the lens S4Pxc ]!  
    parID = FindFullName( "Geometry.Arizona Eye" ) Fe#  1  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) h&M{]E9=  
    count = 0 .8 2P(}h  
    While GetOperationCount(eID)>count >f|||H}Snw  
        GetOperation eID, count, op 034iK[ib"  
        If op.Type="ShiftZ" Then ?1*cO:O  
            DeleteOperation eID,count ^-TE([bW  
            count=count-1 /74QMx?  
        End If ;(b9#b.  
        count=count+1 M-$%Rzl_  
    Wend #%pI(,o=  
    op.Type = "ShiftZ" J-[,KME_^  
    op.val1 = taq-0.01 kGH}[w  
    op.parent = parID +=>,Pto<  
    AddOperation eID, op 7z%L*z8V  
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    Print "Set pupil diameter = " & pupilDiam d8DV[{^  
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    'Update AZ Eye subassembly Description y|jl[pyg)  
    eID = FindFullName( "Geometry.Arizona Eye" ) \q>bs|2  
    GetEntity eID, entity %h hf
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    entity.Description = "Accommodation = " & A & "D" ;d@#XIS&-(  
    SetEntity eID, entity ZFA`s qT  
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    Update %Si6]3-^@  
    Print "DONE!" Yc`o5Q\>  
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End Sub Ozw.siD  
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如果屈光度是4，光瞳直径是4，则会输出如下数据： S%$ }(  
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Accommodation = 4 Diopters L,HhbTRca  
Pupil Diameter = 4 mm n|6Ic,:[  
Set aqueous humor thickness = 2.81 7dN*lks  
Set anterior lens radius = 10.4 and conic constant = -2.375869 rbul8(1h  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 mWv3!i;G<s  
Set lens thickness = 3.927 g6yB6vk  
Set lens index of refraction = 1.42672 ?Lx24*5%  
Set pupil diameter = 4 kF3k7,.8&  
DONE! # ncRb  
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