[分享]Arizona眼睛模型 [复制链接]

简介 JGk3b=K  
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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。 qLQ <1>u  
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模型 {uaZ<4N.  
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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。 <fC@KY>#  
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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. PcHSm/d0e  
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光源 V-KL%  
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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。 A9\]3 LY  
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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。 heE}_,$|  

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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。 >lD;0EN  
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视网膜的散射 ]{f^;y8  
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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。 s<[A0=LH  
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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。 [[:UhrH-  
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脚本 )y9;OA  
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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： {Ge+O<mD  
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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。 ,N53Iic  
余下的脚本计算与屈光度有关的所有参数。 2t+D8 d|c<  
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分析 x^A7'ad0  
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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。 ze`1fO|%  
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脚本代码 )uZoH8?  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. ^:`oP"%-T  
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Dim entity As T_ENTITY !c%  
Dim op As T_OPERATION 9YB2e84j  
Dim mat As T_MODELMATERIAL 9B /s  
Dim A As Double A (Bk@;  
Dim pupilDiam As Double cv}aS_`f  
Dim eID As Long tR kF   
Dim parID As Long 8{dEpV*  
Dim count As Integer !O|ql6^;  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double XAe\s`  
Dim tlens As Double, nlens As Double 2 P=[  
Dim curv As Double, conic As Double pz{'1\_+9  
Dim ok As Long bmu6@jT  
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Sub Main yL6^\x  
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    '用户输入对话框 6^)rv-L~5y  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 )l&D]3$6K  
        TextBox 220,21,40,21,.TextBox1 'default: 0 %SAw;ZtQ:  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 4o<*PPA1  
        OKButton 40,91,90,21 (Yv{{mIy  
        CancelButton 190,91,90,21 qj&bo  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 C5|db{=\.*  
        TextBox 220,49,40,21,.TextBox2 'default: 4 +Mk#9r  
    End Dialog v5_7r%Hiw  
    Dim dlg As UserDialog l
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    ok = Dialog (dlg) #02Kdo&Vy  
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    If ok=0 Then    'cancel button was pressed ldGojnS  
        Print "Execution cancelled." q*,Q5  
        End |~WYEh  
    End If t6+YXjXK  
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    'Assign accommodation and pupil diameter & use defaults if field left empty [:iv4>ZZ  
    If dlg.TextBox1 = "" Then 44\cI]!{  
        A = 0           'Default accommodation /.Fj.6U5  
    Else v!9i"@<!  
        A = CDbl(dlg.TextBox1) dH
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    End If 5{d\uE%'p  
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    If dlg.TextBox2 = "" Then 5rb-U7 /  
        pupilDiam = 4   'Default pupil diameter sYqgXE.  
    Else <_Eg?ePW#  
        pupilDiam = CDbl(dlg.TextBox2) :P$#MC  
    End If P`S@n/}  
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    Print " " Ts9ktPlm  
    Print "Accommodation = " & A & " Diopters" x&Cp> +i  
    Print "Pupil Diameter = " & pupilDiam & " mm" N2ied^* 0  
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    ' Calculate new parameters with accommodation Zp&@h-%YoD  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness (gwj)?:  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens eS'yGY0b  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens vi!YN|}\  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens FY'ty@|_s  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens t P"\J(x  
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    tlens = 3.767 + 0.04*A                  'Lens thickness Wh( |+rJ?Z  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction D\1k.tI  
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    'Adjust parameters to account for accommodation %0,-.(h  
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    '************************************************************************* FS"eM"z  
    'Aqueous thickness (Position of Lens) p`F9Amb  
    '************************************************************************* uuNR?1fS  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) WC,+Cn e  
    GetCustomElement eID, entity =JS;;PzX[  
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    parID = FindFullName( "Geometry.Arizona Eye" ) vUA0FoOp  
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    ' Delete any shift(s) in z  d
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    count = 0 HYK!}&  
    While GetOperationCount(eID)>count *Dmx&F=3,5  
        GetOperation eID, count, op "*z_O  
        If op.Type="ShiftZ" Then K_/zuTy  
            DeleteOperation eID,count _oFs #kW  
            count=count-1 52_#  
        End If Q=uRKh  
        count=count+1 1ocJ+  
    Wend G:W>I=^DaR  
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    'Set new shift in $wB^R(f@  
    op.Type = "ShiftZ" (X[CsaXt  
    op.val1 = taq 5O/i3m26  
    op.parent = parID MJ`3ta  
    AddOperation eID, op en F:>H4  
    Print "Set aqueous humor thickness = " & taq-0.55 bzN-*3YE=  
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    '************************************************************************* '8Ztj  
    'Radius and conic constant of anterior lens nmU_N:Y  
    '************************************************************************* a:,y Z  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) I6!5Yj]O"  
    GetConic eID, entity, curv, conic bx4'en#  
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    SetConic eID, entity, 1/Rant, CCant }n_p$g[Nj/  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant wC_l@7t  
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    '************************************************************************* %+>s#Q2d  
    'Radius and conic constant of posterior lens @Ky> 9m{  
    '************************************************************************* b2,mCfLsv  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) $2^
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    GetConic eID, entity, curv, conic (>4aibA'P  
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    SetConic eID, entity, 1/Rpost, CCpost 51C2u)HE  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost <h).fX  
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    '************************************************************************* OLGBt  
    'Lens thickness (Position of posterior lens surface) xT&(n/  
    '************************************************************************* D4Al3fe  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) }v9\F-0>Q  
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    ' Delete any z-shift(s) M->*{D@a  
    count = 0 '^BV_
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    While GetOperationCount(eID)>count H=
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        GetOperation eID, count, op aprm0:Q^  
        If op.Type="ShiftZ" Then U[L9*=P;  
            DeleteOperation eID,count u]NZ`t%AP  
            count=count-1 bzDIhnw  
        End If =gfI!w  
        count=count+1 Ho DVn/lr  
    Wend ?\KM5^eX  
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    'Set new z-shift H1GRMDNXOA  
    op.Type = "ShiftZ" D4eTTf
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    op.val1 = tlens wbDM5%  
    op.parent = parID NjPDX>R\K  
    AddOperation eID, op a,F&`Wg  
    Print "Set lens thickness = " & tlens ;*ix~taL%  
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    '************************************************************************* e^4 p%  
    'Lens index of refraction >Rvx[`|O!m  
    '************************************************************************* [ EFMu;q  
    eID = FindMaterial( "Lens" ) fO'Wj`&a  
    GetModelMaterial eID, mat D|Iur W1f  
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    mat.Nd = nlens 73{'kK  
    SetModelMaterial eID, mat ^-FX  
    Print "Set lens index of refraction = " & nlens Ol"3a|  
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    '************************************************************************* 8[r9HC  
    'Pupil diameter J PyOG_h  
    '************************************************************************* ,B4VT 96*  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) }X GEX:1K  
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    'Adjust pupil diameter (trimming volume inner hole) M/x>51<  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" j!
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    ' Adjust pupil location to just in front of the lens N#lDW~e'  
    parID = FindFullName( "Geometry.Arizona Eye" ) &g2 Eptx#  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) !fBF|*/  
    count = 0 p!]6ll^  
    While GetOperationCount(eID)>count hcVJBK  
        GetOperation eID, count, op yc|VJ2R*  
        If op.Type="ShiftZ" Then $^u}a  
            DeleteOperation eID,count vR0];{  
            count=count-1 8Ll[ fJZA  
        End If pg]BsJN  
        count=count+1 ]9}HEu;1M  
    Wend =rdY @  
    op.Type = "ShiftZ" Ii7QJ:^  
    op.val1 = taq-0.01 dU\%Cq-G)  
    op.parent = parID iU6Gp-<M,  
    AddOperation eID, op |ZodlYF  
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    Print "Set pupil diameter = " & pupilDiam s1|/S\
  
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    'Update AZ Eye subassembly Description ,=?{("+  
    eID = FindFullName( "Geometry.Arizona Eye" ) _gKe%J&  
    GetEntity eID, entity XeBP`\>Ve  
    entity.Description = "Accommodation = " & A & "D" OL_{_K(w  
    SetEntity eID, entity $}")1|U,X  
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    Update T~h5B(J;  
    Print "DONE!" GUslPnG  
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End Sub 4v[~r1!V  
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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： {'16:dTJ  
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Accommodation = 4 Diopters [r/k% <  
Pupil Diameter = 4 mm 5NJ4  
Set aqueous humor thickness = 2.81 oD}uOC}FS{  
Set anterior lens radius = 10.4 and conic constant = -2.375869 ]Qm]I1P  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 NBb6T V}j  
Set lens thickness = 3.927 bQ|V!mrN}  
Set lens index of refraction = 1.42672 +cU>k}  
Set pupil diameter = 4 ?5kHa_^  
DONE! 1Bxmm#  
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QQ：2987619807 
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