[分享]Arizona眼睛模型 [复制链接]

简介 Bg}l$?S  
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人眼光学模型可用来设计眼科用设备，光学系统注定了要与人眼一起使用。本文演示了这样一个模型：Arizona眼睛模型，在Jim Schwiegerling教授的书中有详细描述：《Field Guide to Visual and Ophthalmic Optics》。AZ眼睛模型达到了基于平均临床数据所决定的轴上和轴外像差等级。FRED文件包含了此眼睛模型及几个用来分析它的光源，并包括一个基于想要的屈光度来调整模型的内嵌脚本。 Qq'e#nI@  
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模型 YRMe<upo  
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模型的定义如表1种所示，由半径、圆锥常数、折射率、阿贝数、到下一面的距离等一系列表面组成。一些参数由屈光度（A）来决定。 nw_s:  
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在FRED中使用0屈光度来创建的，光瞳加在了透镜的前面。材料是创建一个新的材料并选择类型“Model Material”,输入的参数是nd和vd. Uq~b4X$  
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光源 5 D=r7  
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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。 Q @[gj:w  
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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。 ZH*h1?\X  
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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。 sPVE_n  
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视网膜的散射 /DP0K @%  
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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。 5W$Jxuyqj  
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注意在视网膜的表面有散射重点采样规格定义，在“Scatter”标签的底部可获取该信息。“toward pupil”指定散射光朝向光瞳，半角度10度。 tCm]1ZgRW  
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脚本 &W c$VDC  
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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： W-gu*iZ6&  
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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。 QleVW  
余下的脚本计算与屈光度有关的所有参数。
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分析 k{=dV  

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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。 7!h> < sx  
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脚本代码 m(d|TwG{  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. wW/q#kc  
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Dim entity As T_ENTITY F3]VSI6^E,  
Dim op As T_OPERATION 6/?onEL9_  
Dim mat As T_MODELMATERIAL pT3icy!A=  
Dim A As Double 1r_V$o$  
Dim pupilDiam As Double zx,9x*g  
Dim eID As Long 'TuaP`]<  
Dim parID As Long A0U
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Dim count As Integer Pr(@&:v:  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double )J0h\ky  
Dim tlens As Double, nlens As Double awvP;F?q|  
Dim curv As Double, conic As Double h_+  
Dim ok As Long nxx/26{  
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Sub Main %[s%H)e)  
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    '用户输入对话框 Ej 5_d  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 -{8K/!  
        TextBox 220,21,40,21,.TextBox1 'default: 0 XPD1HN!,LT  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 EApbaS}Up  
        OKButton 40,91,90,21 {j;` wN  
        CancelButton 190,91,90,21 K
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        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 '21gUYm  
        TextBox 220,49,40,21,.TextBox2 'default: 4 S4[#[w`=  
    End Dialog k4hk* 0Jq  
    Dim dlg As UserDialog 3Jt# Mp  
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    ok = Dialog (dlg) FMI1[|:;  
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    If ok=0 Then    'cancel button was pressed s.Bb@Jq  
        Print "Execution cancelled." vNrn]v=|}7  
        End i}P{{kMJ  
    End If %Nvw`H  
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    'Assign accommodation and pupil diameter & use defaults if field left empty X<Z(,B  
    If dlg.TextBox1 = "" Then fByf~iv,  
        A = 0           'Default accommodation X?wZ7*'1  
    Else l v hJ  
        A = CDbl(dlg.TextBox1) s</qT6@  
    End If z F.@rXl  
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    If dlg.TextBox2 = "" Then ^r(My}  
        pupilDiam = 4   'Default pupil diameter _8 |X820  
    Else kaB4[u  
        pupilDiam = CDbl(dlg.TextBox2) X~c?C-fV  
    End If 3Cc#{X-+  
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    Print " " %dg[ho  
    Print "Accommodation = " & A & " Diopters" 25-h5$s  
    Print "Pupil Diameter = " & pupilDiam & " mm"  w:QO@  
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    ' Calculate new parameters with accommodation -X~|jF  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness ~'KqiUY  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens /*,_\ ;  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens .6a
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens o!KDeY  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens L*[3rqER  
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    tlens = 3.767 + 0.04*A                  'Lens thickness @x+2b0 b  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction M?%x=q\<  
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    'Adjust parameters to account for accommodation ?X6}+  
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    '************************************************************************* ]kTxVe  
    'Aqueous thickness (Position of Lens) QO(F%&v++  
    '************************************************************************* A8*zB=C  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) &4S2fWx  
    GetCustomElement eID, entity `>)Ge](oN  
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    parID = FindFullName( "Geometry.Arizona Eye" ) D\-\U E/  
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    ' Delete any shift(s) in z  k-=LD  
    count = 0 ~8u *sy  
    While GetOperationCount(eID)>count z77>W}d  
        GetOperation eID, count, op .E}lAd.Mn  
        If op.Type="ShiftZ" Then Gb\PubJ  
            DeleteOperation eID,count qz>R"pj0g  
            count=count-1 .Lna\Bv  
        End If /~{`!30  
        count=count+1 ~BmA!BZV`  
    Wend M lR~`B}m  
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    'Set new shift in 71{jedT  
    op.Type = "ShiftZ"  |50sGJE(  
    op.val1 = taq !EhKg)y=  
    op.parent = parID c Pf_B=  
    AddOperation eID, op 4v hz`1  
    Print "Set aqueous humor thickness = " & taq-0.55 Pa{  
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    '************************************************************************* >9dD7FH  
    'Radius and conic constant of anterior lens `IUn{I  
    '************************************************************************* Jq'8"  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) 1d<Uwb>  
    GetConic eID, entity, curv, conic 4>>=TJ!M  
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    SetConic eID, entity, 1/Rant, CCant '6 F-%
 
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant i9DD)Y<  
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    '************************************************************************* l\*9rs:!  
    'Radius and conic constant of posterior lens aLGq<6Ja  
    '************************************************************************* o6k#neB>=.  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) ~(QfVpRnV=  
    GetConic eID, entity, curv, conic jRS{7rx%MH  
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    SetConic eID, entity, 1/Rpost, CCpost vyIH<@@p7  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost 2+ cs^M3  
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    '************************************************************************* M}V!;o<t^  
    'Lens thickness (Position of posterior lens surface) 5dj@N3ZX7;  
    '************************************************************************* ?1SsF>|  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) ^Fco'nlM  
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    ' Delete any z-shift(s) Zp9. ~&4o-  
    count = 0 %'=*utOxy  
    While GetOperationCount(eID)>count i.vH$  
        GetOperation eID, count, op  S=(O6+U  
        If op.Type="ShiftZ" Then 00QJ596  
            DeleteOperation eID,count P9 <U+\z  
            count=count-1 \xkKgI/  
        End If bx8](cT_  
        count=count+1 TJO$r6&  
    Wend h^yqrDyJ  
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    'Set new z-shift 27e!KG[&  
    op.Type = "ShiftZ" N7+L@CC6T  
    op.val1 = tlens _5jT}I<k  
    op.parent = parID _F;v3|`D@<  
    AddOperation eID, op 0Ds3wNz  
    Print "Set lens thickness = " & tlens ) CP  
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    '************************************************************************* KhHFJo[8sf  
    'Lens index of refraction "La;$7ds  
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    eID = FindMaterial( "Lens" ) YA4D?'  
    GetModelMaterial eID, mat o8bdL<  
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    mat.Nd = nlens }X&rJV  
    SetModelMaterial eID, mat U#` e~d t<  
    Print "Set lens index of refraction = " & nlens 'dLw8&T+W  
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    '************************************************************************* @%]A,\  
    'Pupil diameter m+TAaK  
    '*************************************************************************
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    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) -zR<m  
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    'Adjust pupil diameter (trimming volume inner hole) Iux3f+H  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" FE~D:)Xj'?  
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    ' Adjust pupil location to just in front of the lens &|/_"*uM  
    parID = FindFullName( "Geometry.Arizona Eye" ) zR"cj  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) ANM#Kx+  
    count = 0 1@F-t94I  
    While GetOperationCount(eID)>count 6>a6;[  
        GetOperation eID, count, op BzzC|
 
        If op.Type="ShiftZ" Then VfX^iG r  
            DeleteOperation eID,count 4
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            count=count-1 =RQF::[h  
        End If `^bP9X_a  
        count=count+1 O$,Fga  
    Wend )kpEcMlR  
    op.Type = "ShiftZ" qO#3{kW  
    op.val1 = taq-0.01 u
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    op.parent = parID )6OD@<r{  
    AddOperation eID, op u
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    Print "Set pupil diameter = " & pupilDiam {M]_]L{&7  
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    'Update AZ Eye subassembly Description x< A-Ws{^V  
    eID = FindFullName( "Geometry.Arizona Eye" ) uoS:-v}/Y~  
    GetEntity eID, entity +V3mF_s|z  
    entity.Description = "Accommodation = " & A & "D" .H" ?&Mf  
    SetEntity eID, entity o*cu-j3  
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    Update aZOn01v;!&  
    Print "DONE!" X?5{2ulrI  
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End Sub A3jxjQ  
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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： (8duV  

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Accommodation = 4 Diopters (jT)o,IW&  
Pupil Diameter = 4 mm 5 ~Wg=u<6  
Set aqueous humor thickness = 2.81 uzYB`H<  
Set anterior lens radius = 10.4 and conic constant = -2.375869 sy: xA w  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 nBh+UT}  
Set lens thickness = 3.927 Q_5l.M/9]  
Set lens index of refraction = 1.42672 z$~x 2<  
Set pupil diameter = 4 LOh2eZ"
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DONE! <DF3!r  
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