[技术]Arizona眼睛模型 [复制链接]

简介 ?$T^L"~  
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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。 "qd|!:bE  
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模型 k!}(a0h  
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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。 Z)2d
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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. ^L)TfI_n  
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光源 `GdH ,:S>  
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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。 'Grii,  
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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。 T!ZjgCY}  
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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。 xPPA8~Dm*  
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视网膜的散射 ;?tH8jf>  
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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。 \Ta5c31S+  
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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。 BDvkY  
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脚本 GDSXBa*7  
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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： \t&!
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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。 %UrNPk  
余下的脚本计算与屈光度有关的所有参数。 yRyXlZC  
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分析 +]A,fmI.  
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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。 o>C,Db~L/  
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脚本代码 ))f@9m  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. G=|?aK{p  
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Dim entity As T_ENTITY Dg.~"h5mT  
Dim op As T_OPERATION e'A_4;~@s  
Dim mat As T_MODELMATERIAL K~,!IU_QG  
Dim A As Double wGNEb  
Dim pupilDiam As Double 1C{0
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Dim eID As Long <<u]WsW{C  
Dim parID As Long *6` ^8Y\  
Dim count As Integer %xCL&}bY  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double JCnHEH
 
Dim tlens As Double, nlens As Double <q!HY~"V  
Dim curv As Double, conic As Double P
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Dim ok As Long @i!+Z  
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Sub Main -Yse^(^"s  
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    '用户输入对话框 ocWl]h].  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 e}yF2|0FD  
        TextBox 220,21,40,21,.TextBox1 'default: 0 ,$:u^;V(  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 eLPtdP5k  
        OKButton 40,91,90,21 ygnZ9ikh<-  
        CancelButton 190,91,90,21 ejZ-A?f-K  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 9;v3 (U+:  
        TextBox 220,49,40,21,.TextBox2 'default: 4 #X'-/q`.  
    End Dialog pLCj"D).M  
    Dim dlg As UserDialog YGOkq
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    ok = Dialog (dlg) STjb2t,a  
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    If ok=0 Then    'cancel button was pressed "zJxWXI  
        Print "Execution cancelled." 9nc_$H{  
        End 8iaMr278W  
    End If lqOpADLS3  
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    'Assign accommodation and pupil diameter & use defaults if field left empty ai$l7]7  
    If dlg.TextBox1 = "" Then ?wG  
        A = 0           'Default accommodation /!5ohQlPJ  
    Else hbJy<e1W  
        A = CDbl(dlg.TextBox1) VVch%  
    End If #BP0MY&  
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    If dlg.TextBox2 = "" Then $7Hwu^c(  
        pupilDiam = 4   'Default pupil diameter wE.jf.q  
    Else a%m )8N;C  
        pupilDiam = CDbl(dlg.TextBox2) jy.L/s  
    End If '6qH@r4Z<  
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    Print " "  ,c`6-  
    Print "Accommodation = " & A & " Diopters" b}Gm{;s!  
    Print "Pupil Diameter = " & pupilDiam & " mm" h SS9mQ  
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    ' Calculate new parameters with accommodation Fz(
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    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness 6Zn[l,\  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens 8Gy]nD  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens _@XueNU1hS  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens liPrxuP`  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens w,j!%N  
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    tlens = 3.767 + 0.04*A                  'Lens thickness 1YMi4.  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction JJ)  
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    'Adjust parameters to account for accommodation dLH@,EKl)  
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    '************************************************************************* n-M6~   
    'Aqueous thickness (Position of Lens) 9'H:pb2  
    '************************************************************************* B^TgEr  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) SHPDbBS  
    GetCustomElement eID, entity N~v<8vJq`  
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    parID = FindFullName( "Geometry.Arizona Eye" ) ?E!M%c@,  
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    ' Delete any shift(s) in z uaP5(hUI  
    count = 0 $bMmyDw  
    While GetOperationCount(eID)>count V_$<^z|  
        GetOperation eID, count, op j07A>G-=  
        If op.Type="ShiftZ" Then <Ffru?o4
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            DeleteOperation eID,count >?JUGXAi'{  
            count=count-1 <bW~!lv  
        End If aj1g9y  
        count=count+1 30I-E._F  
    Wend ? }ff O  
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    'Set new shift in Xbx=h^S  
    op.Type = "ShiftZ" 1 Lg{l  
    op.val1 = taq #lMIs4i.  
    op.parent = parID \25EI]  
    AddOperation eID, op $HOe){G  
    Print "Set aqueous humor thickness = " & taq-0.55 A?n5;mvq#  
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    '************************************************************************* :_HdOm  
    'Radius and conic constant of anterior lens DQu)?Rsk  
    '************************************************************************* a6:hH@,  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) #G(ivRo  
    GetConic eID, entity, curv, conic X^&--@l}T!  
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    SetConic eID, entity, 1/Rant, CCant ,\+N}F^  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant t; #@t/`  
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    '************************************************************************* {l/`m.Z  
    'Radius and conic constant of posterior lens D5Rp<PBq,  
    '************************************************************************* Dby|l#X  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) M).CyY;bm  
    GetConic eID, entity, curv, conic Zonn  
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    SetConic eID, entity, 1/Rpost, CCpost >@G"*le*)  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost MR4k#{:w  
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    '************************************************************************* 73u97oe>1  
    'Lens thickness (Position of posterior lens surface) w?*79 u  
    '************************************************************************* ep5`&g]3  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) 4,YL15.  
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    ' Delete any z-shift(s) 'bH~KK5  
    count = 0 Y0Tw:1a  
    While GetOperationCount(eID)>count _ A{F2M  
        GetOperation eID, count, op z&#^9rM"  
        If op.Type="ShiftZ" Then )iC@n8f7o  
            DeleteOperation eID,count k=p[Mlic/  
            count=count-1 b ~]v'|5[  
        End If 
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        count=count+1 gE*7[*2?t  
    Wend u^'X>n)oL#  
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    'Set new z-shift yZoJD{'?Sw  
    op.Type = "ShiftZ" 9zx9t  
    op.val1 = tlens ;2?fz@KZ  
    op.parent = parID GKUjtPu  
    AddOperation eID, op 4kV$JV.l  
    Print "Set lens thickness = " & tlens [\fwn
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    '************************************************************************* ]sP  
    'Lens index of refraction %ib7)8Ki0  
    '************************************************************************* X
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    eID = FindMaterial( "Lens" ) rkdA4'66w  
    GetModelMaterial eID, mat ]TtID4qL  
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    mat.Nd = nlens )L":I  
    SetModelMaterial eID, mat I 5ZDP|  
    Print "Set lens index of refraction = " & nlens nsq7dhq  
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    '************************************************************************* z.h;}QRJ,@  
    'Pupil diameter +4qR5
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    '************************************************************************* ,j(E>g3  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) Ck m:;q  
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    'Adjust pupil diameter (trimming volume inner hole) tK#/S+l  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" %SCt_9u  
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    ' Adjust pupil location to just in front of the lens MU '-  
    parID = FindFullName( "Geometry.Arizona Eye" ) k1P'Q&Na  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) p*1B*R  
    count = 0 d}|z+D  
    While GetOperationCount(eID)>count MlS5/9m@^  
        GetOperation eID, count, op 3-Xd9ou  
        If op.Type="ShiftZ" Then "So"oT1
 
            DeleteOperation eID,count xjAU Csq  
            count=count-1 /Q89y[  
        End If 7dE.\#6r  
        count=count+1 ?h|DeD!s  
    Wend m9DTz$S.  
    op.Type = "ShiftZ" f+)LVT8p  
    op.val1 = taq-0.01 $n47DW&  
    op.parent = parID #2Vq"Zn  
    AddOperation eID, op w7q6v>  
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    Print "Set pupil diameter = " & pupilDiam ,S`FxJcE  
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    'Update AZ Eye subassembly Description +nB0O/m'U  
    eID = FindFullName( "Geometry.Arizona Eye" ) Ty7`&  
    GetEntity eID, entity $Tt.r  
    entity.Description = "Accommodation = " & A & "D" {(tR<z)  
    SetEntity eID, entity sint":1FC  
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    Update \;Q!}_ K  
    Print "DONE!" 5'`DrTOA  
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End Sub -Oz! GX  
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如果屈光度是4，光瞳直径是4，则会输出如下数据： ,R7j9#D  
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Accommodation = 4 Diopters VP~%,=  
Pupil Diameter = 4 mm z_A\\  
Set aqueous humor thickness = 2.81 4+p1`  
Set anterior lens radius = 10.4 and conic constant = -2.375869 nKEw$~F  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 OJM2t`}_t  
Set lens thickness = 3.927 _)YB
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Set lens index of refraction = 1.42672 VpY,@qh  
Set pupil diameter = 4 j+gh*\:q  
DONE! l0ZK)