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    [转载]FRED运用:Arizona眼睛模型 [复制链接]

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    只看楼主 倒序阅读 楼主  发表于: 2016-02-24
    简介 6;:D!},'c  
    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。 ) 9 2(C  
    0Fon`3(^\  
    模型 qD\9h`a  
    4U}J?EB?K  
    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。 6,jCO@!   
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    Table 1. AZ眼睛模型的定义
    !ry+{v+A  
    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. dmXfz D  
    LTzdg >\oJ  
    光源 Ssz;d&93  
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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。 |n tWMm:(  
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    图1. 光源和提示信息使用
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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。 Y DHP-0?  
    K-\wx5#l/  
    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。 0fBwy/:  
    ~7KH/%Z-  
    图2. 字母F光源的设定方法光 @:PMb Ub  
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    图3. 字母F在视网膜上位置点列图
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    视网膜的散射 ^o _J0 ]m  
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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。 gl`J(  
    t7u*j-YE  
    &}Wi@;G]2  
    图4. 视网膜朗伯散射设定
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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。 1;c>#20  
    "|dhmV[;  
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    图5. 视网膜重点采样规格设定
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    脚本 #[x*0K-h  
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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: CC"a2Hu/  
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    图6. 用户对话框的创建与编辑
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    图7. 用户对话框编辑器
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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。 'v0rnIsI?  
    余下的脚本计算与屈光度有关的所有参数。 gy,)% {,G  
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    分析 p.8  
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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。 |4pl}:g/Z  
    B=n90XO |  
    图7. 字母F在视网膜上颜色分析
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    脚本代码 VK*`&D<P  
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    Option Explicit     'Remove this to enable non-dimensioned variables to be used. b+ycEs=_  
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    Dim entity As T_ENTITY <+q`Dk  
    Dim op As T_OPERATION NrXIaN  
    Dim mat As T_MODELMATERIAL \ILNx^$EL  
    Dim A As Double '&,p>aM  
    Dim pupilDiam As Double :/5G Hfyj  
    Dim eID As Long ic!% }S?  
    Dim parID As Long }AB_i'C0  
    Dim count As Integer DBaZcO(U  
    Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double uK(]@H7~!c  
    Dim tlens As Double, nlens As Double (n>Gi;u(R  
    Dim curv As Double, conic As Double `p* 43nV  
    Dim ok As Long J%r:"Jm[y1  
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    Sub Main Uvc$&j^k  
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        '用户输入对话框 {j`8XWLZZN  
        Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 S},Cz  
            TextBox 220,21,40,21,.TextBox1 'default: 0 ^J hs/HV  
            Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 k\SqDmv  
            OKButton 40,91,90,21 rA?< \*  
            CancelButton 190,91,90,21 T _UJ?W  
            Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 (j@c946z""  
            TextBox 220,49,40,21,.TextBox2 'default: 4 JCBX?rM/  
        End Dialog O"o|8 l}M/  
        Dim dlg As UserDialog #*y.C[^5{  
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        ok = Dialog (dlg) @VIY=qh  
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        If ok=0 Then    'cancel button was pressed ??.aLeF&  
            Print "Execution cancelled." |X XO0  
            End J| wk})?  
        End If hPz=Ec<zW  
    WH39=)D%u  
        'Assign accommodation and pupil diameter & use defaults if field left empty ,66(*\xT  
        If dlg.TextBox1 = "" Then p&<n_b  
            A = 0           'Default accommodation d(RMD  
        Else C:^ :^y  
            A = CDbl(dlg.TextBox1) V*2 * 5hx  
        End If k1yqe rA  
    <{;'0> ToM  
        If dlg.TextBox2 = "" Then r 9M3rj]  
            pupilDiam = 4   'Default pupil diameter ?Q"<AL>Z  
        Else 7\yh(+kN  
            pupilDiam = CDbl(dlg.TextBox2) - uO(qUa#  
        End If 4B[pQlg  
    T;{}bc&I  
        Print " " ?,v& o>*  
        Print "Accommodation = " & A & " Diopters" Ho*B<#&(A|  
        Print "Pupil Diameter = " & pupilDiam & " mm" WwWOic2  
    G~u$BV'  
        ' Calculate new parameters with accommodation <<gW`KF   
        taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness ;3& wO~lW  
    >)*d/^  
        Rant = 12.0 - 0.4*A                     'Radius of anterior lens  gsi2  
        CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens *5s*-^'#!  
    ]:2Ro:4Yv  
        Rpost = -5.224557 + 0.2*A               'Radius of posterior lens baTd;`Pn  
        CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens "x;FE<I  
    @mg5vt!$`  
        tlens = 3.767 + 0.04*A                  'Lens thickness SQU@JKi; g  
    1uKIO{d @  
        nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction Ho(}_Q&  
    m;xa}b{(i  
        'Adjust parameters to account for accommodation A-L)2.M  
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        '************************************************************************* o2$A2L9P  
        'Aqueous thickness (Position of Lens) ZR|s]'  
        '************************************************************************* Wql=PqF  
        eID = FindFullName( "Geometry.Arizona Eye.Lens" ) 1TfFWlf[B  
        GetCustomElement eID, entity ~~"U[G1  
    |=VWE>g  
        parID = FindFullName( "Geometry.Arizona Eye" ) Ny`SE\B+/  
    |cuKC \  
        ' Delete any shift(s) in z jJvd!,=)  
        count = 0 @Q nKaZ8jW  
        While GetOperationCount(eID)>count 1\/vS$bi(  
            GetOperation eID, count, op Si23w'T  
            If op.Type="ShiftZ" Then ]Y->EME:W  
                DeleteOperation eID,count =I&BO[d  
                count=count-1 v5?)J91  
            End If }c= Y<Cdh  
            count=count+1 [z7]@v6b  
        Wend zd$iD i($  
    `e7vSp  
        'Set new shift in = 4|"<8'  
        op.Type = "ShiftZ" &jg>X+;  
        op.val1 = taq ]0(ZlpT  
        op.parent = parID S_??G:i  
        AddOperation eID, op pV:44  
        Print "Set aqueous humor thickness = " & taq-0.55 wM;=^br  
    MZX@Gi<S[  
        '************************************************************************* &E!m(|6?+  
        'Radius and conic constant of anterior lens B2_fCSlg  
        '************************************************************************* , .=7{y~  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) ?/@XJcm+  
        GetConic eID, entity, curv, conic ;.$vDin6  
    HKOSS-`5  
        SetConic eID, entity, 1/Rant, CCant x2b t^!t.  
        Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant MX!N?k#KhP  
    *YQXxIIq  
        '************************************************************************* ZtGk Md$  
        'Radius and conic constant of posterior lens ,|zwY~l t5  
        '************************************************************************* /9D mK%d  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) Ho&f[T(  
        GetConic eID, entity, curv, conic |?f~T"|>  
    ^K~=2^sh  
        SetConic eID, entity, 1/Rpost, CCpost i"DyXIrk2  
        Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost 6y?uH; SL  
    0d~?|Nv -  
        '************************************************************************* [(8s\>T  
        'Lens thickness (Position of posterior lens surface) H#nJWe_9A  
        '************************************************************************* &g*1If  
    mB bGj3u;  
        parID = FindFullName( "Geometry.Arizona Eye.Lens" ) J=O_nup6C  
    G$/Qcr6W<  
        ' Delete any z-shift(s) g86^Z%c(k  
        count = 0 :Us+u-~  
        While GetOperationCount(eID)>count x @9rc,by  
            GetOperation eID, count, op q!5`9u6  
            If op.Type="ShiftZ" Then !@T~m1L eY  
                DeleteOperation eID,count z<yqQ[  
                count=count-1 v`7~#Avhz  
            End If Fy6Lz.baB  
            count=count+1 (Nf!E[ }Z  
        Wend Ck/w:i@>?  
    @qA11C.hq  
        'Set new z-shift jEP'jib%  
        op.Type = "ShiftZ" i{HzY[  
        op.val1 = tlens gKWUHlQY  
        op.parent = parID :2A-;P4  
        AddOperation eID, op ):L0{W{  
        Print "Set lens thickness = " & tlens 3|URlz  
    zE}ry!{  
        '************************************************************************* {e[~1]j3  
        'Lens index of refraction 9r8bSV3`  
        '************************************************************************* 6s! =de  
        eID = FindMaterial( "Lens" ) A*]sN8  
        GetModelMaterial eID, mat ojIGfQV  
    `'bu8JK  
        mat.Nd = nlens <hgfgk7<  
        SetModelMaterial eID, mat N{Pa&/V  
        Print "Set lens index of refraction = " & nlens zrC1/%T  
    Je K0><  
        '************************************************************************* I "R<XX  
        'Pupil diameter kidv^`.H$w  
        '************************************************************************* m^tf=O<  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) #Qu|9Q[QH  
    9wC='  
        'Adjust pupil diameter (trimming volume inner hole) PvxU.  
    G/1V4-@  
        SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" ]0}NF  
    og*ti!Z  
        ' Adjust pupil location to just in front of the lens `@<)#9'A  
        parID = FindFullName( "Geometry.Arizona Eye" ) eQ =6< ^KZ  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) )@ .0ai  
        count = 0 U[ogtfv`m  
        While GetOperationCount(eID)>count J b7^'P  
            GetOperation eID, count, op [bBPs&7u  
            If op.Type="ShiftZ" Then !}"PHby5N  
                DeleteOperation eID,count 2P|j<~JS  
                count=count-1 t6%zfm   
            End If j 4(f1  
            count=count+1 'H1k  
        Wend sA,2gbW  
        op.Type = "ShiftZ"  I$fm"N  
        op.val1 = taq-0.01 .;:dG  
        op.parent = parID Z,, qmwd  
        AddOperation eID, op RAxp2uif  
    ipRH.1=  
        Print "Set pupil diameter = " & pupilDiam *Oh]I|?  
    z&.F YGq}  
        'Update AZ Eye subassembly Description lBG"COu  
        eID = FindFullName( "Geometry.Arizona Eye" ) ,@8*c0Y~<!  
        GetEntity eID, entity e{ZS"e`!  
        entity.Description = "Accommodation = " & A & "D" `] Zil8n  
        SetEntity eID, entity 4tp }  
    c 1{nOx  
        Update };>~P%u32  
        Print "DONE!" ~8lB#NuN  
         t8~isuiK  
    End Sub %^;rYn3  
    Rw!_j!  
    如果屈光度是4,光瞳直径是4,则会输出如下数据: Xc G   
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    Accommodation = 4 Diopters |Tk'H&  
    Pupil Diameter = 4 mm 7)x 788Z6  
    Set aqueous humor thickness = 2.81 +,4u1`c|$  
    Set anterior lens radius = 10.4 and conic constant = -2.375869 )JR&  
    Set posterior lens radius = -4.424557 and conic constant = -3.081019 s)kr=zdyo  
    Set lens thickness = 3.927 A+"'8%o9}  
    Set lens index of refraction = 1.42672 $69d9g8-(!  
    Set pupil diameter = 4  ByjgM`  
    DONE! FMqes5\ 3  
    W`jKe-jF  
    (文章来源:讯技光电)
     
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