[技术]Arizona眼睛模型 [复制链接]

简介 f0Zn3
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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。 n `Ry!  
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模型 n+qa/<  
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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。 azT@S=,  
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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. 2,bLEhu  
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光源 ek9Y9eJ"  
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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。 Y%"73.x  
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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$)&;Q  
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在往下看是内置的脚本用来修改屈光度，使其为4（250mm），光源“Letter F”在视网膜处生成一个字母为F的图像。绿色的光线聚焦的非常好而红色和蓝色光线有一点的模糊。使用Positions Spot Diagram分析工具来观察最为合适。 >ngP\&\  
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视网膜的散射 .*acw  
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在散射文件中，有一个名为“Retina surface”的72%的反射型朗伯散射，它为视网膜的散射提供了一个粗略的近似。为了模拟来自视网膜的散射，改变自定义元件“Eye ball” 下的视网膜的表面从“halt all” 到”Allow All”。并使几何中“plane”可追迹。 J3P)oM[  
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注意在视网膜的表面有散射重点采样规格定义，在“Scatter”标签的底部可获取该信息。“toward pupil”指定散射光朝向光瞳，半角度10度。 B4d\4S_r%  
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脚本 f 3t&Bcw$  
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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： -w#*~Q{'*  
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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。 d>OLnG> F  
余下的脚本计算与屈光度有关的所有参数。 Okt0b|=`1*  
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分析 t=B>t S.hO  
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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。 +#Q\;;FNP  
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脚本代码 AIK99  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. Fu;\t 0  
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Dim entity As T_ENTITY ']]5xH*U  
Dim op As T_OPERATION _t'S<jTI  
Dim mat As T_MODELMATERIAL 5l]G1+  
Dim A As Double g E#43  
Dim pupilDiam As Double :<w2j6V  
Dim eID As Long |?=a84n1l  
Dim parID As Long A.@/~\  
Dim count As Integer a"6AZT"8  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double |
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Dim tlens As Double, nlens As Double zUNWcv!& "  
Dim curv As Double, conic As Double \4qwLM?E^  
Dim ok As Long 5&QDZnsl  
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Sub Main BXx0Z %e.3  
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    '用户输入对话框 q5D_bm7,3  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 E` O@UW@  
        TextBox 220,21,40,21,.TextBox1 'default: 0 9f/RD?(1O  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 =iZj&B X  
        OKButton 40,91,90,21 fP:26pK^  
        CancelButton 190,91,90,21 Za4X ;  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 G,]%dZHe  
        TextBox 220,49,40,21,.TextBox2 'default: 4 qC;1ND  
    End Dialog Jx
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    Dim dlg As UserDialog wE*jN~  
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    ok = Dialog (dlg) 6%nKrK  
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    If ok=0 Then    'cancel button was pressed h0v4!`PQ-  
        Print "Execution cancelled." a9<
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        End E/[
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    End If IC[iCrB  
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    'Assign accommodation and pupil diameter & use defaults if field left empty LEJ8 .z6$  
    If dlg.TextBox1 = "" Then V/; / &  
        A = 0           'Default accommodation nm3/-Q},  
    Else `EjPy>kM  
        A = CDbl(dlg.TextBox1) [LcHO] _^M  
    End If ]EhU8bZ  
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    If dlg.TextBox2 = "" Then K@DK4{  
        pupilDiam = 4   'Default pupil diameter %M/rpEE"b%  
    Else V< ]l=JOd  
        pupilDiam = CDbl(dlg.TextBox2) Vu u2SS  
    End If `fA|])3T  
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    Print " " @mbR I0  
    Print "Accommodation = " & A & " Diopters" 9~FB^3Nz_  
    Print "Pupil Diameter = " & pupilDiam & " mm" e,0y+~  
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    ' Calculate new parameters with accommodation ,*Vt53@E  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness m:{ws~
  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens /!//i^  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens Fo0dz  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens !VF.=\iH/  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens O_n) 2t(c?  
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    tlens = 3.767 + 0.04*A                  'Lens thickness Sjogv  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction n%"0%A  
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    'Adjust parameters to account for accommodation n qR8uL>  
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    '************************************************************************* /<\B8^yQ  
    'Aqueous thickness (Position of Lens) D02_ Jrg  
    '************************************************************************* mROXwzL
 
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) $G_,$U!  
    GetCustomElement eID, entity 8LH"j(H  
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    parID = FindFullName( "Geometry.Arizona Eye" ) qq)Dh'5*e,  
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    ' Delete any shift(s) in z m3La;%aA0  
    count = 0 tmCm54  
    While GetOperationCount(eID)>count 0."TSe83\  
        GetOperation eID, count, op 6jGPmOM/  
        If op.Type="ShiftZ" Then =h#3D?b0n  
            DeleteOperation eID,count `k>h2(@9S  
            count=count-1 <`~zKFUQ[  
        End If U!0 Qf7D  
        count=count+1 ?2#v`Z=L;  
    Wend &?-LL{W{  
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    'Set new shift in cP4K9:k  
    op.Type = "ShiftZ" PhS`,I^Z  
    op.val1 = taq Mk*&CNo3  
    op.parent = parID /Ww_
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    AddOperation eID, op jf_0I
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    Print "Set aqueous humor thickness = " & taq-0.55 nmLn]U=  
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    '************************************************************************* jmcb-=ts  
    'Radius and conic constant of anterior lens :[#~,TW  
    '************************************************************************* E%f;Z7G  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) g' xR$6t  
    GetConic eID, entity, curv, conic }WN0L?h.E  
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    SetConic eID, entity, 1/Rant, CCant 1D,$Az~.  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant 7*7Z&1*3  
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    '************************************************************************* rb/m;8v>  
    'Radius and conic constant of posterior lens Qo4+=^(  
    '************************************************************************* p8>.Q/4  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) 5 W<\J  
    GetConic eID, entity, curv, conic $uA?c& e  
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    SetConic eID, entity, 1/Rpost, CCpost _d8k[HAJ|  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost \L
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    '************************************************************************* q<YteuZJ,  
    'Lens thickness (Position of posterior lens surface) Yfk){1  
    '************************************************************************* c !$ 8>  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) +DWmutL  
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    ' Delete any z-shift(s) AxaabS$\  
    count = 0 VQm)32'  
    While GetOperationCount(eID)>count 1_Um6vS#  
        GetOperation eID, count, op
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        If op.Type="ShiftZ" Then ~ caKzq  
            DeleteOperation eID,count $c-h'o  
            count=count-1 RLypWjMx$
 
        End If "t<${  
        count=count+1 U/ncD F%C  
    Wend ?|8QL9Q"|  
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    'Set new z-shift 't$(Ruw  
    op.Type = "ShiftZ" {iP^51fy  
    op.val1 = tlens Wgl7)Xk.)  
    op.parent = parID `U4R% qhWA  
    AddOperation eID, op ^A8'YTl  
    Print "Set lens thickness = " & tlens G>?hojvi  
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    '************************************************************************* ?_e2)+q8YG  
    'Lens index of refraction KzeTf?G  
    '************************************************************************* m6BIQ(l  
    eID = FindMaterial( "Lens" ) (+<SR5,/3  
    GetModelMaterial eID, mat z6)SaSYE  
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    mat.Nd = nlens ,gAa9  
    SetModelMaterial eID, mat X@;; h  
    Print "Set lens index of refraction = " & nlens />^sGB  
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    '************************************************************************* G)~/$EF,_  
    'Pupil diameter +S/OMkC  
    '************************************************************************* "m2g"xa\7  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) FfEP@$  
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    'Adjust pupil diameter (trimming volume inner hole) ZSWKVTi  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" 2>`m1q:  
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    ' Adjust pupil location to just in front of the lens 3vdhoS|  
    parID = FindFullName( "Geometry.Arizona Eye" ) cX~J6vNy5  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) ))M!"*  
    count = 0 '0ks`a4q  
    While GetOperationCount(eID)>count z{;~$."  
        GetOperation eID, count, op mO#62e4C  
        If op.Type="ShiftZ" Then !q]@/<=  
            DeleteOperation eID,count R3 Zg,YM  
            count=count-1 N{kp^Byim0  
        End If o'Rr2,lVi  
        count=count+1 dV/ ^@[  
    Wend $W_sIS0\z  
    op.Type = "ShiftZ" Lp1\vfU<+  
    op.val1 = taq-0.01 MgpjC`  
    op.parent = parID c+a"sx\  
    AddOperation eID, op eHX;*~e6)  
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    Print "Set pupil diameter = " & pupilDiam 85e!)I_  
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    'Update AZ Eye subassembly Description )\O;Rt(  
    eID = FindFullName( "Geometry.Arizona Eye" ) )#%v1rR  
    GetEntity eID, entity .I h'&  
    entity.Description = "Accommodation = " & A & "D" p)&Yr  
    SetEntity eID, entity ~7;AV(\%e  
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    Update Al}D~6MD  
    Print "DONE!" 0(o{V:l%Z|  
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End Sub V'iT>  
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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： ,SV34+(
 
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Accommodation = 4 Diopters 4QZ|e{t  
Pupil Diameter = 4 mm i:/Ws1=q  
Set aqueous humor thickness = 2.81 c9/&A  
Set anterior lens radius = 10.4 and conic constant = -2.375869 cqd}.D  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 ~~iFs ,9  
Set lens thickness = 3.927 tX.fbL@T  
Set lens index of refraction = 1.42672 fVvB8[(;~  
Set pupil diameter = 4 H$M{thW  
DONE! Oaj$Z- f