[技术]Arizona眼睛模型 [复制链接]

简介 OBAO(Ke  
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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。 0#]fEi  
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模型 N1~bp?$1  
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模型的定义如表1种所示，由半径、圆锥常数、折射率、阿贝数、到下一面的距离等一系列表面组成。一些参数由屈光度（A）来决定。 8TP$?8l  
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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. x0<;Rm [u=  
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光源 Fv~lasW[  
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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。 ;@ePu  
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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。 Q VTL}AT2:  
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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。 ETHcZ  
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视网膜的散射 k+h}HCzE  
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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。 M/<ypJ  
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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。 9\_s&p=:.  
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脚本 ;73S;IPR  
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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： l?m"o-Gp3  
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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。 #kW=|8X  
余下的脚本计算与屈光度有关的所有参数。 JG!B3^qB  
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分析 e/D{^*~S  
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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。 >#
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脚本代码 [7@blU  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. [edF'7La  
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Dim entity As T_ENTITY u2#q7}  
Dim op As T_OPERATION qR@ESJ_  
Dim mat As T_MODELMATERIAL Dge#e  
Dim A As Double .V;,6Vq
 
Dim pupilDiam As Double \tgY2:  
Dim eID As Long )g:5}+  
Dim parID As Long d4b!  r  
Dim count As Integer -m`|Sq  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double +~"IF+TRH  
Dim tlens As Double, nlens As Double (:b
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Dim curv As Double, conic As Double v^&HZk=(  
Dim ok As Long Mk*4J]PP  
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Sub Main FF8jW1  
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    '用户输入对话框 b~.$1oZ  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1  LDg9@esi  
        TextBox 220,21,40,21,.TextBox1 'default: 0 s\d3u`G  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 Gpu[<Z4  
        OKButton 40,91,90,21 n{QyqI  
        CancelButton 190,91,90,21 mlByE,S2E  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 .F ?ww}2p]  
        TextBox 220,49,40,21,.TextBox2 'default: 4 t=7Gfv
 
    End Dialog ':4ny]F  
    Dim dlg As UserDialog 2VV>?s  
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    ok = Dialog (dlg) ]G["TX,  
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    If ok=0 Then    'cancel button was pressed K\-N'M!Z  
        Print "Execution cancelled." B
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        End U4d7-&U  
    End If ^y>V-R/N  
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    'Assign accommodation and pupil diameter & use defaults if field left empty Z.${WZW  
    If dlg.TextBox1 = "" Then  m}yu4  
        A = 0           'Default accommodation va@;V+cD  
    Else l4RqQ+[KA;  
        A = CDbl(dlg.TextBox1) @JSWqi>  
    End If !8p>4|VM  
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    If dlg.TextBox2 = "" Then />xEpR3_A  
        pupilDiam = 4   'Default pupil diameter k)knyEUi  
    Else t3$cX_  
        pupilDiam = CDbl(dlg.TextBox2) S*Ea" vBA  
    End If OXLB{|hH80  
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    Print " " xiW}P% bf  
    Print "Accommodation = " & A & " Diopters" @6ckB (  
    Print "Pupil Diameter = " & pupilDiam & " mm" R V#w0 r  
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    ' Calculate new parameters with accommodation 0-p^oA  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness -, +o*BP  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens ` ,T.  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens \WE/#To  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens ky !ZJR  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens ]Z[3 \~?  
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    tlens = 3.767 + 0.04*A                  'Lens thickness L@MCB-@V  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction 0^{Tq0Ri[  
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    'Adjust parameters to account for accommodation J|xXo
  
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    '************************************************************************* T \34<+n1N  
    'Aqueous thickness (Position of Lens)  e$  
    '************************************************************************* BSS4}qyS  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) e`+  
    GetCustomElement eID, entity GGHMpQ   
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    parID = FindFullName( "Geometry.Arizona Eye" ) bIT[\Q  
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    ' Delete any shift(s) in z Il/`#b@h  
    count = 0 ^/2O_C  
    While GetOperationCount(eID)>count 9on$0  
        GetOperation eID, count, op [GknE#p  
        If op.Type="ShiftZ" Then '\H & EJ'  
            DeleteOperation eID,count hpOY&7QUTD  
            count=count-1 i_Lu  
        End If \R&ZWJKh  
        count=count+1 d>M0:  
    Wend 0Wd5s{S  
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    'Set new shift in j.Y!E<e4]  
    op.Type = "ShiftZ" jhG6,;1zMI  
    op.val1 = taq t":^:i'M  
    op.parent = parID \(Dm\7Q.  
    AddOperation eID, op #)D$\0ag  
    Print "Set aqueous humor thickness = " & taq-0.55 S@\&^1;4Hv  
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    '************************************************************************* ]$K5
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    'Radius and conic constant of anterior lens fNr*\=$  
    '************************************************************************* aS3-A4  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) <O9WCl  
    GetConic eID, entity, curv, conic ygm=q^bV]s  
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    SetConic eID, entity, 1/Rant, CCant };(2 na  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant 09Oe-Bg  
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    '************************************************************************* N}bZdE9F  
    'Radius and conic constant of posterior lens IxG0TJ_  
    '************************************************************************* Ejf>QIB  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) |b Z 58{}  
    GetConic eID, entity, curv, conic F8m@mh*8>  
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    SetConic eID, entity, 1/Rpost, CCpost ue *mTMN  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost #$t93EI  
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    '************************************************************************* 0J)VEMC
  
    'Lens thickness (Position of posterior lens surface) Se/]J<]  
    '************************************************************************* ]N'4q}<5o  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) (B+zh  
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    ' Delete any z-shift(s) #|xj*+)H  
    count = 0 6mrfkYK  
    While GetOperationCount(eID)>count ?IG+U TI  
        GetOperation eID, count, op [0NH#88ym<  
        If op.Type="ShiftZ" Then ,J-YfL^x6*  
            DeleteOperation eID,count ``?Z97rH  
            count=count-1 () HIcu*i  
        End If j"+R*H(#  
        count=count+1 doe u`  
    Wend )vur$RX  
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    'Set new z-shift 9/GC8*+  
    op.Type = "ShiftZ" [\i1I`7pE  
    op.val1 = tlens z2V_nkI  
    op.parent = parID < uzDuBN  
    AddOperation eID, op W{'tS{  
    Print "Set lens thickness = " & tlens -,xsUw4  
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    '************************************************************************* I'uRXvEr7  
    'Lens index of refraction == i?lbj  
    '************************************************************************* 'v3>"b  
    eID = FindMaterial( "Lens" ) /?8rj3  
    GetModelMaterial eID, mat 'r`-J4icX  
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    mat.Nd = nlens Q,f5r%A.  
    SetModelMaterial eID, mat G0h7MO%x  
    Print "Set lens index of refraction = " & nlens t5za$kW'&  
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    '************************************************************************* +l$BUX  
    'Pupil diameter ,}#l0BY  
    '************************************************************************* B1gBvss  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) 3
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    'Adjust pupil diameter (trimming volume inner hole) uod&'g{N  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" bjJ212J  
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    ' Adjust pupil location to just in front of the lens HTCn=MZm ?  
    parID = FindFullName( "Geometry.Arizona Eye" ) wN!5[N"  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) 6d3-GMUQ  
    count = 0 ]q@6&]9  
    While GetOperationCount(eID)>count %,*{hhfu  
        GetOperation eID, count, op co%ttH\ n  
        If op.Type="ShiftZ" Then {^ ^)bf|1'  
            DeleteOperation eID,count D@>^_cTO24  
            count=count-1 dAcy;-[[P  
        End If 5eWGX  
        count=count+1 c`&<"Us  
    Wend DrB PC@^  
    op.Type = "ShiftZ" WY%'ps_]<  
    op.val1 = taq-0.01 EWg\\90  
    op.parent = parID #4*~ 4/  
    AddOperation eID, op M1T)e9k=x  
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    Print "Set pupil diameter = " & pupilDiam r6`v-TY(/  
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    'Update AZ Eye subassembly Description v9OK <  
    eID = FindFullName( "Geometry.Arizona Eye" ) x-/`c  
    GetEntity eID, entity R"=pAO.4l  
    entity.Description = "Accommodation = " & A & "D" dw!cDfT+  
    SetEntity eID, entity =X11x)]F9  
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    Update n_51-^*z  
    Print "DONE!" Q=%1@ ,x"  
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End Sub =q(;g]e  
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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： m. G}#/  
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Accommodation = 4 Diopters {? jr  
Pupil Diameter = 4 mm M38QA  
Set aqueous humor thickness = 2.81 x\Bl^1&  
Set anterior lens radius = 10.4 and conic constant = -2.375869 4cni_m]  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 ^{GnE
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Set lens thickness = 3.927 8rXu^  
Set lens index of refraction = 1.42672
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Set pupil diameter = 4 m]$!wp  
DONE! 54w..8'