[技术]Arizona眼睛模型 [复制链接]

简介 :S%|^QAN  
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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。 1rN&Y,61\  
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模型 rg $71Ir  
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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。 (cMrEuv  
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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. Ji7A9Hk  
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光源 xv)7-jlx  
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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。 ljk-xC p/  
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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。 {d3r>Ub)7d  
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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。 )Ev [o#y  
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视网膜的散射 Qdtfi1_Y1  
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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。 HezCRtxRcc  
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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。 KsHMAp3  
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脚本 (;s\Ip0  
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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。 ov|s5yH8e  
余下的脚本计算与屈光度有关的所有参数。 K%Rx5 
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分析 (5atU |8r  
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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。 Z'u`)jR  

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脚本代码 nc`[fy|}  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. u|Db%)
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Dim entity As T_ENTITY &gq\e^0CRZ  
Dim op As T_OPERATION tv?~LJYN  
Dim mat As T_MODELMATERIAL ost~<4~  
Dim A As Double a1s=t_w
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Dim pupilDiam As Double W/+|dN{O+g  
Dim eID As Long !QYqRH~5  
Dim parID As Long N<?RN;M  
Dim count As Integer @O4m-Oosi  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double _7 n+j  
Dim tlens As Double, nlens As Double YRB,jwne  
Dim curv As Double, conic As Double R|Ykez!D  
Dim ok As Long .lqo>Ta y  
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Sub Main f^nogw<z!  
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    '用户输入对话框 1z*]MYU  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 TlM ]d;9G  
        TextBox 220,21,40,21,.TextBox1 'default: 0 @1rF9< 4g  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 _<xU"8b"5  
        OKButton 40,91,90,21 i1  
        CancelButton 190,91,90,21 %vMi kibI  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 R$v{ p[  
        TextBox 220,49,40,21,.TextBox2 'default: 4 Z
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    End Dialog _e/vw:  
    Dim dlg As UserDialog uGgR@+7?Z  
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    ok = Dialog (dlg) I2D<~xP~2+  
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    If ok=0 Then    'cancel button was pressed FJ~Dg3F1  
        Print "Execution cancelled." 5q" ;R$+j  
        End ?. CA9!|   
    End If $T~|@XH  
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    'Assign accommodation and pupil diameter & use defaults if field left empty 670g|&v.  
    If dlg.TextBox1 = "" Then YW}1Mf=_  
        A = 0           'Default accommodation H<"{wUPT0  
    Else (5VP*
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        A = CDbl(dlg.TextBox1) <+C]^*j  
    End If {cC9 }w  
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    If dlg.TextBox2 = "" Then ~[l2"@  
        pupilDiam = 4   'Default pupil diameter / [:@j+n\  
    Else +d]}  
        pupilDiam = CDbl(dlg.TextBox2) irpO(>LK  
    End If `[7&tOvSk  
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    Print " " G+=&\+{#4  
    Print "Accommodation = " & A & " Diopters" 7w YSP&$  
    Print "Pupil Diameter = " & pupilDiam & " mm" s+^YGB  
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    ' Calculate new parameters with accommodation j[9xF<I  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness 5"k_Ms7R,  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens :,6dW?mun6  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens ]#TL~u[  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens M'Q{2%:>a  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens -7hU1j~I  
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    tlens = 3.767 + 0.04*A                  'Lens thickness ,RDxu7iT  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction zZGPA j  
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    'Adjust parameters to account for accommodation ~1i,R1_\Y  
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    '************************************************************************* C KBLM2D  
    'Aqueous thickness (Position of Lens) I Yj\t?,0  
    '************************************************************************* q^>$YY>F  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) i8+kc_8#d  
    GetCustomElement eID, entity 2-. g>'W  
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    parID = FindFullName( "Geometry.Arizona Eye" ) A<QYW,:|  
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    ' Delete any shift(s) in z DTI+VY.W^  
    count = 0 `{<2{}2M  
    While GetOperationCount(eID)>count _)ZAf%f?  
        GetOperation eID, count, op {>pB  
        If op.Type="ShiftZ" Then JPS L-j  
            DeleteOperation eID,count _LxV)  
            count=count-1 Y+F$]!hw  
        End If [p_R?2uT  
        count=count+1 X_
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    Wend HkGzy
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    'Set new shift in L5]*ZCDv  
    op.Type = "ShiftZ" `LVXK|m+$  
    op.val1 = taq 0`3ey*  
    op.parent = parID x.<^L] "  
    AddOperation eID, op ;XZ5r|V}  
    Print "Set aqueous humor thickness = " & taq-0.55 Zj
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    '************************************************************************* gXE'3  
    'Radius and conic constant of anterior lens ^4`q%_vm  
    '************************************************************************* gh['T,  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) mv)M9c,`  
    GetConic eID, entity, curv, conic RT F9;]Ti  
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    SetConic eID, entity, 1/Rant, CCant #B&D  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant 7Z93`A-=  
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    '************************************************************************* hJrxb<9@Y0  
    'Radius and conic constant of posterior lens ph<Z/wlz  
    '************************************************************************* H7H'0C  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) NV^ktln  
    GetConic eID, entity, curv, conic cs8bRXjHa  
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    SetConic eID, entity, 1/Rpost, CCpost VQ$=F8ivG  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost xEOR\(Z^  
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    '************************************************************************* 0/#XUX 4  
    'Lens thickness (Position of posterior lens surface) 7Q/v#_e(  
    '************************************************************************* psta&u\ q  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) m Wsegq4  
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    ' Delete any z-shift(s) 49@ pA-  
    count = 0 L`V6\Ix(I  
    While GetOperationCount(eID)>count sYYg5vL9  
        GetOperation eID, count, op G$xuHHZ'  
        If op.Type="ShiftZ" Then EJNj.c-#  
            DeleteOperation eID,count Km'd=B>Jy  
            count=count-1 O (tcu@vfl  
        End If X6N^<Z$  
        count=count+1 3BKW  
    Wend !,V8?3.aJn  
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    'Set new z-shift 5lxC**NA  
    op.Type = "ShiftZ" K}1>n2P  
    op.val1 = tlens wpb6F '  
    op.parent = parID /d0LD  
    AddOperation eID, op +O*S>0  
    Print "Set lens thickness = " & tlens `g6Z
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    '************************************************************************* o{f n}  
    'Lens index of refraction \@*cj8e  
    '************************************************************************* 3S_KycE{  
    eID = FindMaterial( "Lens" ) &+J5GHt@  
    GetModelMaterial eID, mat H \.EKZ  
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    mat.Nd = nlens Y GO ;wIS  
    SetModelMaterial eID, mat H_o<!YxK  
    Print "Set lens index of refraction = " & nlens Q^Y>T&Q  
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    '************************************************************************* u8~.6]Ae  
    'Pupil diameter Ud*.[GRD~  
    '************************************************************************* VrQw;-rQ  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) TAi |]U!  
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    'Adjust pupil diameter (trimming volume inner hole) S;Lqx5Cd  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" tCI8\~  
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    ' Adjust pupil location to just in front of the lens oQjh?vm  
    parID = FindFullName( "Geometry.Arizona Eye" ) OC7:Dp4  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) =uKK{\+|Y  
    count = 0 6$%]p1"!K  
    While GetOperationCount(eID)>count ZT
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        GetOperation eID, count, op [\@!~F{  
        If op.Type="ShiftZ" Then RgRyo  
            DeleteOperation eID,count 85w D<bN27  
            count=count-1 Mf%/t HK  
        End If v9x $`  
        count=count+1 YV.*8'*  
    Wend +M-' K19  
    op.Type = "ShiftZ" _@F4s  
    op.val1 = taq-0.01 wZE[we^Q"  
    op.parent = parID 96}/;e]@  
    AddOperation eID, op ?9Fv0-g&n  
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    Print "Set pupil diameter = " & pupilDiam vTh-I&}:  
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    'Update AZ Eye subassembly Description yE{l Xp;  
    eID = FindFullName( "Geometry.Arizona Eye" ) {|%5}\%  
    GetEntity eID, entity >^+Q`"SN  
    entity.Description = "Accommodation = " & A & "D" <saS2
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    SetEntity eID, entity \^|ncu:T  
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    Update ;yBq'_e3  
    Print "DONE!" cK@O)Ko}  
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End Sub &|n*&@fF  
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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： yc_(L-'n  
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Accommodation = 4 Diopters l"CHI*  
Pupil Diameter = 4 mm z*zLK[t+  
Set aqueous humor thickness = 2.81 }b)?o@9}:  
Set anterior lens radius = 10.4 and conic constant = -2.375869 va~:oA  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 \@MGOaR]  
Set lens thickness = 3.927 5c'rnMW4+p  
Set lens index of refraction = 1.42672 Wj8\~B=('  
Set pupil diameter = 4 3|P P+<o  
DONE! f>#\'+l'