[分享]Arizona眼睛模型 [复制链接]

简介 g)$/'RB  
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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。 [wU e"{  
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模型 f~Y;ZvB  
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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。 YTpiOPf  
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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. OQW%nF9~  
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光源 Kb
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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。 L4O.=*P1  
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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。 $%B
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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。 Cj%n?-
  
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视网膜的散射 [ Y+Ta,  
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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。 [)+wke9  
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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。 (E;+E\E  
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脚本 oyB gF\  
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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： *\.8
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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。 "uli~ {IU  
余下的脚本计算与屈光度有关的所有参数。 y'aK92pF:  
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分析 @)\4 $#+-  
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屈光度为4，光瞳直径为4mm，字母F点在视网膜上所成的像。  nU4to  
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脚本代码 W#)X@TlE  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. cJMi`PQ;  
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Dim entity As T_ENTITY ]]0Yh  
Dim op As T_OPERATION y8_$YA/g  
Dim mat As T_MODELMATERIAL t"zi'9$t  
Dim A As Double {dXTj7  
Dim pupilDiam As Double AsD$M*It  
Dim eID As Long 5(gWK{R)*  
Dim parID As Long z&cM8w:  
Dim count As Integer lEg
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Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double t~7OtPF  
Dim tlens As Double, nlens As Double 0kSM$D_  
Dim curv As Double, conic As Double Q^;:
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Dim ok As Long IyI0|&r2A  
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Sub Main O\CnKNk,  
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    '用户输入对话框 "~=-Q#xO  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 ,z<1:
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        TextBox 220,21,40,21,.TextBox1 'default: 0 3.@LAF  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 y XKddD  
        OKButton 40,91,90,21 EK= y!
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        CancelButton 190,91,90,21 RC}m]!Uz  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 #i.,+Q  
        TextBox 220,49,40,21,.TextBox2 'default: 4 "u]&~$  
    End Dialog C6EGM/m8  
    Dim dlg As UserDialog ,{m
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    ok = Dialog (dlg) Vpne-PW  
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    If ok=0 Then    'cancel button was pressed PtYG%/s  
        Print "Execution cancelled." Y)DAR83  
        End Pz34a@%"  
    End If O/|))H?C  
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    'Assign accommodation and pupil diameter & use defaults if field left empty jz`3xFy *]  
    If dlg.TextBox1 = "" Then I?St}Tl  
        A = 0           'Default accommodation k_{?{:X;y  
    Else 67hfve  
        A = CDbl(dlg.TextBox1) ^*i0~_  
    End If Q5ff&CE  
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    If dlg.TextBox2 = "" Then 5[g\.yi2_]  
        pupilDiam = 4   'Default pupil diameter pmUf*u-
 
    Else J^`5L7CO  
        pupilDiam = CDbl(dlg.TextBox2) ,#FP]$FK  
    End If [zBi*%5O  
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    Print " " A+!,{G  
    Print "Accommodation = " & A & " Diopters" R|}N"J_  
    Print "Pupil Diameter = " & pupilDiam & " mm" Pw| h`[h  
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    ' Calculate new parameters with accommodation J,:&U wkv  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness Bcarx<P-p  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens En1LGi4#  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens W^H3=hZ  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens /zt M'  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens PWyf3  
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    tlens = 3.767 + 0.04*A                  'Lens thickness JC%&d
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction H)i|?3Ip  
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    'Adjust parameters to account for accommodation *Q^z4UY  
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    '************************************************************************* n Syq}Y3  
    'Aqueous thickness (Position of Lens) r":anR( ;  
    '************************************************************************* IC&P-X_aP  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) A $gn{ c  
    GetCustomElement eID, entity 3q}j"x?  
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    parID = FindFullName( "Geometry.Arizona Eye" ) jtlRom}  
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    ' Delete any shift(s) in z hK{H7Ey*  
    count = 0 }1e4u{  
    While GetOperationCount(eID)>count Z.Yq)\it  
        GetOperation eID, count, op q6)fP4MQ]  
        If op.Type="ShiftZ" Then <M@-|K"Eb  
            DeleteOperation eID,count GM0
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            count=count-1 xy[#LX)RW  
        End If /3,Lp-kp
 
        count=count+1 NDP" @  
    Wend :${tts2g  
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    'Set new shift in VwE4:/7YN  
    op.Type = "ShiftZ" >< $LV&  
    op.val1 = taq /T)E&=Ds  
    op.parent = parID o]4\Geg$  
    AddOperation eID, op &jHsFS  
    Print "Set aqueous humor thickness = " & taq-0.55 R,G*]/r`  
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    '************************************************************************* X}v*"`@Q  
    'Radius and conic constant of anterior lens T:$^1"\  
    '************************************************************************* ![\-J$  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) %`
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    GetConic eID, entity, curv, conic h<U?WtWT-p  
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    SetConic eID, entity, 1/Rant, CCant o=3hWbe  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant O`9c!_lis  
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    '************************************************************************* >MHlrSH2  
    'Radius and conic constant of posterior lens Bi:lC5d5?  
    '************************************************************************* rk W7;!  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) x%=CEe?6  
    GetConic eID, entity, curv, conic Wr%ov6:  
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    SetConic eID, entity, 1/Rpost, CCpost i]%f94  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost Mq
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    '************************************************************************* <bKtAf  
    'Lens thickness (Position of posterior lens surface) >#|%'Us  
    '************************************************************************* cRVL1ne  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) TU0-L35P1  
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    ' Delete any z-shift(s) Io]FDPN  
    count = 0 P35DVKS  
    While GetOperationCount(eID)>count =0
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        GetOperation eID, count, op HrBJi  
        If op.Type="ShiftZ" Then = ^NvUrK  
            DeleteOperation eID,count G;l7,1;MU:  
            count=count-1 A)&FcMO*z  
        End If R@\}iyM  
        count=count+1 (`.OS)&  
    Wend R ZY=c  
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    'Set new z-shift 32[}@f2q  
    op.Type = "ShiftZ" X&pYLm72;  
    op.val1 = tlens [tpiU'/Zl  
    op.parent = parID <?nIO
  
    AddOperation eID, op );gY8UL^  
    Print "Set lens thickness = " & tlens Tn}`VW~  
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    '************************************************************************* !%G]~  
    'Lens index of refraction r)iEtT!p*  
    '************************************************************************* <k:I2LF_  
    eID = FindMaterial( "Lens" )  + Q-b}  
    GetModelMaterial eID, mat ;5j|B|v  
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    mat.Nd = nlens hC<ROD  
    SetModelMaterial eID, mat VL9wRu;  
    Print "Set lens index of refraction = " & nlens ^c\O,*:  
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    '************************************************************************* y&NqVR=  
    'Pupil diameter nje7?Vz  
    '************************************************************************* ~Ru\Z-q1  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) 4X
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    'Adjust pupil diameter (trimming volume inner hole) $o[-xNn1  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" =0)|psCsM  
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    ' Adjust pupil location to just in front of the lens (9]Uuvfp6"  
    parID = FindFullName( "Geometry.Arizona Eye" ) <7^|@L 6  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) +0pI}a\  
    count = 0 ]RCo@QW  
    While GetOperationCount(eID)>count y(COB6r  
        GetOperation eID, count, op ${ {4L?7  
        If op.Type="ShiftZ" Then ,{_i{WV  
            DeleteOperation eID,count / FcRp,"  
            count=count-1 Mn0.!J "  
        End If yLa@27T\A  
        count=count+1 9M96$i`P  
    Wend Z=JKBoAY  
    op.Type = "ShiftZ" X1^VdJE  
    op.val1 = taq-0.01 ^Oz~T
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    op.parent = parID 46:<[0Psl/  
    AddOperation eID, op \O|S
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    Print "Set pupil diameter = " & pupilDiam PIri|ZS  
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    'Update AZ Eye subassembly Description F!vrvlD`s  
    eID = FindFullName( "Geometry.Arizona Eye" ) .WF"vUp  
    GetEntity eID, entity LDt6<D8,Q  
    entity.Description = "Accommodation = " & A & "D" 4=yzf  
    SetEntity eID, entity ?2<) Jw  
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    Update hfwJZ\_60  
    Print "DONE!" 9Dx~!(  
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End Sub b'z $S+  
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如果屈光度是4，光瞳直径是4，则会输出如下数据： R]"Zv'M(AM  
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Accommodation = 4 Diopters ,>j3zjf^  
Pupil Diameter = 4 mm 6<&A}pp  
Set aqueous humor thickness = 2.81 uMcI'=  
Set anterior lens radius = 10.4 and conic constant = -2.375869 N^;lp<{6?  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 !1$x4 qxS  
Set lens thickness = 3.927 1w>[&#7  
Set lens index of refraction = 1.42672 4$Ai!a  
Set pupil diameter = 4 i 8sv,P  
DONE! ' @!&{N  
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