[技术]Arizona眼睛模型 [复制链接]

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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。 IwBO#HR
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模型 r9*6=*J|  
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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。 \GV'{W+o2  
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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. 4 L 5$=V  
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光源 Z?d][zGw  
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多个光源定义来分析该模型的不同特性。图1显示了所以的光源和提示信息告诉您他们可以用来做什么。 6Eus_aP  
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除了“Letter F”之外的所有光源的光线位置设定在了孔径光阑位置处，并增加了pre-propagation distance= -8。尽管光线在光瞳处创建，规定的传输方向相对于光线位置在pre-propagation distance之后。这意味着光束沿着Z轴在眼睛的前面以平行光入射，而不是在光瞳处入射。 # 2FrP5rC  
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在往下看是内置的脚本用来修改屈光度，使其为4（250mm），光源“Letter F”在视网膜处生成一个字母为F的图像。绿色的光线聚焦的非常好而红色和蓝色光线有一点的模糊。使用Positions Spot Diagram分析工具来观察最为合适。 K"hnGYt?  
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视网膜的散射 U(Bmffn4Z  
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在散射文件中，有一个名为“Retina surface”的72%的反射型朗伯散射，它为视网膜的散射提供了一个粗略的近似。为了模拟来自视网膜的散射，改变自定义元件“Eye ball” 下的视网膜的表面从“halt all” 到”Allow All”。并使几何中“plane”可追迹。 ~]`U)Aw  
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注意在视网膜的表面有散射重点采样规格定义，在“Scatter”标签的底部可获取该信息。“toward pupil”指定散射光朝向光瞳，半角度10度。 o q6^  
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脚本 O<$j}?2  
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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： o9yUJ@ :i  
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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。 vP+qwvpGr  
余下的脚本计算与屈光度有关的所有参数。 UR S=1+  
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分析 "!fwIEG  
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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。 c.5u \I9"  
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脚本代码 'i:lV'  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. 8J
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Dim entity As T_ENTITY =fdW H4  
Dim op As T_OPERATION yq<W+b/  
Dim mat As T_MODELMATERIAL #/8 Nav  
Dim A As Double ZR"qrCSw`  
Dim pupilDiam As Double e\f\CMb  
Dim eID As Long o*"Q{Xh#Qd  
Dim parID As Long M _lLP8W}  
Dim count As Integer !4<A|$mQ  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double XW\ 3ttx  
Dim tlens As Double, nlens As Double k7L4~W  
Dim curv As Double, conic As Double ,H<nNBv3M  
Dim ok As Long c,M"a  
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Sub Main }RYPr  
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    '用户输入对话框 yF_/.mI  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 {*r!oD!'  
        TextBox 220,21,40,21,.TextBox1 'default: 0 \3%3=:  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 q_L. Sy|)  
        OKButton 40,91,90,21 (H:A|Lw  
        CancelButton 190,91,90,21 84i0h$Z
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        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 4L4u
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        TextBox 220,49,40,21,.TextBox2 'default: 4 =W2I0nr.  
    End Dialog a<>cbP  
    Dim dlg As UserDialog wlslG^^(!  
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    ok = Dialog (dlg) w>}n1Nc$G  
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    If ok=0 Then    'cancel button was pressed ,^<39ng  
        Print "Execution cancelled." qV,x)y:V  
        End zwP*7u$CH  
    End If \q24E3zS&  
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    'Assign accommodation and pupil diameter & use defaults if field left empty qK~]au:C  
    If dlg.TextBox1 = "" Then
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        A = 0           'Default accommodation "{3|(Qs  
    Else HCe/!2Y/%  
        A = CDbl(dlg.TextBox1) BQeg-M  
    End If 5B8fz;l= B  
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    If dlg.TextBox2 = "" Then #e[r0f?U  
        pupilDiam = 4   'Default pupil diameter aSJD'u4w.a  
    Else _F^NX%  
        pupilDiam = CDbl(dlg.TextBox2) 5lM 3In@  
    End If jHA(mU)b  
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    Print " " Qv;b$by3  
    Print "Accommodation = " & A & " Diopters" >?G!>kw  
    Print "Pupil Diameter = " & pupilDiam & " mm" JS<w43/j  
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    ' Calculate new parameters with accommodation A1z<2.R  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness QA)"3g   
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens r?^L/HGc  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens ~XvMiWuo  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens /'_Yct=  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens Gc5mR9pV   
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    tlens = 3.767 + 0.04*A                  'Lens thickness CDr0QM4k:.  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction jMX|1b  
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    'Adjust parameters to account for accommodation 77 Z:!J|  
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    '************************************************************************* t#-4edB,  
    'Aqueous thickness (Position of Lens) u09D`QPP]  
    '************************************************************************* MI.OOoP3a  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) AI,E9  
    GetCustomElement eID, entity beV+3HqB8  
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    parID = FindFullName( "Geometry.Arizona Eye" ) U^K8^an$  
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    ' Delete any shift(s) in z &Wk:>9]Jrb  
    count = 0 f'qM?GlET  
    While GetOperationCount(eID)>count yLl:G;  
        GetOperation eID, count, op y`/:E<fVk  
        If op.Type="ShiftZ" Then ,ZO?D|M1  
            DeleteOperation eID,count R+/kx#^  
            count=count-1 5a2;@}%V  
        End If R4zOiBi'B  
        count=count+1 `>lY$EBG@[  
    Wend A,7* 52U  
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    'Set new shift in lACS^(  
    op.Type = "ShiftZ" BgB0  
    op.val1 = taq gzlRK^5  
    op.parent = parID whGtVx|zR
 
    AddOperation eID, op 9PaV*S(\TR  
    Print "Set aqueous humor thickness = " & taq-0.55 3J3wKw!`  
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    '************************************************************************* e#WASHZN  
    'Radius and conic constant of anterior lens li#ep?5h^  
    '************************************************************************* J$`5KbT3  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) o+- 0`!yj  
    GetConic eID, entity, curv, conic SWT)M1O2  
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    SetConic eID, entity, 1/Rant, CCant |F qujZz  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant >]Dn,*R  
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    '************************************************************************* rV*Ri~Vx  
    'Radius and conic constant of posterior lens Oz"_KMz  
    '************************************************************************* "od2i
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    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" )
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    GetConic eID, entity, curv, conic j|[>f  
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    SetConic eID, entity, 1/Rpost, CCpost f%q ?  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost $wl_  
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    '************************************************************************* 3wPUP+)c7  
    'Lens thickness (Position of posterior lens surface) 2cZgG^  
    '************************************************************************* i7&ay\+@  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) [?XP[h gd  
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    ' Delete any z-shift(s) [<jU$93E  
    count = 0 /8"rCh|m-  
    While GetOperationCount(eID)>count {GGP8  
        GetOperation eID, count, op
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        If op.Type="ShiftZ" Then Pa?C-Xn^  
            DeleteOperation eID,count FU)=+m  
            count=count-1 aeEio;G1  
        End If |>wGl  
        count=count+1 @S&QxE^  
    Wend $Xs`'>,"  
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    'Set new z-shift J2$,'(!(  
    op.Type = "ShiftZ" Kv ajk~  
    op.val1 = tlens yMpZ-b$*~  
    op.parent = parID =i},$"Bf*%  
    AddOperation eID, op f7;<jj;w7  
    Print "Set lens thickness = " & tlens N]F}Z#h  
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    '************************************************************************* cXb&Rm'L  
    'Lens index of refraction h1$75E?,  
    '************************************************************************* J"XZnb)E=  
    eID = FindMaterial( "Lens" ) mgb+HNH%q\  
    GetModelMaterial eID, mat c/l^;6O/!\  
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    mat.Nd = nlens Sf2xI'  
    SetModelMaterial eID, mat v]
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    Print "Set lens index of refraction = " & nlens _s}`ohKvD  
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    '************************************************************************* TK0W=&6#A  
    'Pupil diameter k[y^7,r  
    '************************************************************************* ;R$2+9  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) |FSp`P  
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    'Adjust pupil diameter (trimming volume inner hole) Mt@Ma ]!  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" y~Mu~/s  
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    ' Adjust pupil location to just in front of the lens K87
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    parID = FindFullName( "Geometry.Arizona Eye" ) Zh`[A9I/  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) ,E"n7*6mr  
    count = 0 2q*wYuc  
    While GetOperationCount(eID)>count Xv+,Z<>iQ  
        GetOperation eID, count, op lAkg47i  
        If op.Type="ShiftZ" Then /<Z3x _c  
            DeleteOperation eID,count e`Co ='  
            count=count-1 Lb{.}  
        End If }i^$ li@  
        count=count+1 1\g r ;b  
    Wend r;+a%?P  
    op.Type = "ShiftZ" (O&HCT|  
    op.val1 = taq-0.01 8isQL  
    op.parent = parID R*2F)e\|  
    AddOperation eID, op [2!C^\t  
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    Print "Set pupil diameter = " & pupilDiam \u;`Lf  
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    'Update AZ Eye subassembly Description <,X=M6$0n  
    eID = FindFullName( "Geometry.Arizona Eye" ) 7y_<BCx h  
    GetEntity eID, entity nYe:$t3F=  
    entity.Description = "Accommodation = " & A & "D" }'K-1:  
    SetEntity eID, entity -aV(6i*n  
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    Update *]nk{jo2  
    Print "DONE!" 9!.S9[[N  
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End Sub k=&n>P  
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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： Wfy+9"-;s  
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Accommodation = 4 Diopters Ejnk\8:  
Pupil Diameter = 4 mm =|2F?  
Set aqueous humor thickness = 2.81 fK2r6D9  
Set anterior lens radius = 10.4 and conic constant = -2.375869 A6 `a  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 :6/$/`I0W  
Set lens thickness = 3.927 HJP~ lg  
Set lens index of refraction = 1.42672 T\bpeky~  
Set pupil diameter = 4 =^\?{oV  
DONE! "oyBF CW