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    [分享]Arizona眼睛模型 [复制链接]

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    只看楼主 正序阅读 楼主  发表于: 2020-12-09
    简介 7&2CLh  
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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。 \tfhF#'  
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    模型 ]GiDfYs7%  
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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。 uDMyO<\  
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    Table 1. AZ眼睛模型的定义
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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. A}CpyRVCn  
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    光源 KV|ywcGhT  
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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。 +IM6 GeH  
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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。 * oru;=D@8  
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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。 hQ Lh}}B  
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    图2. 字母F光源的设定方法光 Dl_SEf6b  
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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 h<FEe~  
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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。 i; 3qMBVY~  
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    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。 0zqTX< A  
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    图5. 视网膜重点采样规格设定
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    脚本 jAOD&@z1  
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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: .iH#8Z  
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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。 `L?9-)m<f  
    余下的脚本计算与屈光度有关的所有参数。 Q)Zk UmW  
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    分析 ;@I}eZ,f$  
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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。 \ /6m  
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    图7. 字母F在视网膜上颜色分析
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    脚本代码 IP+1 :M  
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    Option Explicit     'Remove this to enable non-dimensioned variables to be used. s*W)BK|+?  
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    Dim entity As T_ENTITY 1~Z Kpvu  
    Dim op As T_OPERATION POvpaPAZ<  
    Dim mat As T_MODELMATERIAL s\ i.pd:Q  
    Dim A As Double QtsyMm  
    Dim pupilDiam As Double Ss{  
    Dim eID As Long Eb=;D1)y]  
    Dim parID As Long 3a#j&]  
    Dim count As Integer n)rF!a  
    Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double O5p]E7/e  
    Dim tlens As Double, nlens As Double fO{E65uA  
    Dim curv As Double, conic As Double AAt<{  
    Dim ok As Long ?#X`Eu  
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    Sub Main g_w4}!|  
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        '用户输入对话框 Q{Lsr,  
        Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 5-pz/%,  
            TextBox 220,21,40,21,.TextBox1 'default: 0 O[fgn;@|  
            Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 DeTZl+qm1E  
            OKButton 40,91,90,21 GQ8r5V4:  
            CancelButton 190,91,90,21 .o5r;KD  
            Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 !j.jvI%e;  
            TextBox 220,49,40,21,.TextBox2 'default: 4 _A .?:'-  
        End Dialog 20f):A6  
        Dim dlg As UserDialog /< CjBW:  
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        ok = Dialog (dlg) (N\Zz*PLz  
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        If ok=0 Then    'cancel button was pressed fE/8;v!=  
            Print "Execution cancelled." jsvD[\P  
            End y]`@%V2P  
        End If #YSUPO%F  
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        'Assign accommodation and pupil diameter & use defaults if field left empty [\&Mo]"0  
        If dlg.TextBox1 = "" Then ]-aeoa#  
            A = 0           'Default accommodation $|YIr7?R  
        Else uOrvmb  
            A = CDbl(dlg.TextBox1) bMD'teJ  
        End If %?EOD=e =  
    "ppT<8Qi'  
        If dlg.TextBox2 = "" Then TPds)osZT  
            pupilDiam = 4   'Default pupil diameter SS;QPWRZ  
        Else 'gojP  
            pupilDiam = CDbl(dlg.TextBox2) FZ/l T-"  
        End If <nj[=C4v  
    %zyMWC  
        Print " " (K+TqJw  
        Print "Accommodation = " & A & " Diopters" Xze   
        Print "Pupil Diameter = " & pupilDiam & " mm" >1tGQ cg  
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        ' Calculate new parameters with accommodation OR^Wd  
        taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness y=\jQ6Fc  
    Sh]x`3 ).  
        Rant = 12.0 - 0.4*A                     'Radius of anterior lens kI3-G~2  
        CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens l1N{ujM  
    >{4pEy  
        Rpost = -5.224557 + 0.2*A               'Radius of posterior lens tGd<{nF%2  
        CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens IR%a+;Xs  
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        tlens = 3.767 + 0.04*A                  'Lens thickness d #a  
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        nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction ) ZOmv  
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        'Adjust parameters to account for accommodation >UJ&noUD#:  
    _:'m/K3Ee  
        '************************************************************************* B:z-?u#B  
        'Aqueous thickness (Position of Lens) ok\+$+ $ju  
        '************************************************************************* gqD`1/  
        eID = FindFullName( "Geometry.Arizona Eye.Lens" ) gH\r# wy|  
        GetCustomElement eID, entity 9rao&\eH  
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        parID = FindFullName( "Geometry.Arizona Eye" ) 2a=WT`xf ?  
    2,&lGyV#  
        ' Delete any shift(s) in z *!9/`zW  
        count = 0 2c%}p0<;|?  
        While GetOperationCount(eID)>count d=qpTb;(  
            GetOperation eID, count, op R C (v#G  
            If op.Type="ShiftZ" Then hCT%1R}rKr  
                DeleteOperation eID,count u."fJ2}l0X  
                count=count-1 kM3BP& 3m1  
            End If 4Ro(r sO  
            count=count+1 R[&lk~a{=  
        Wend q qzQKN  
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        'Set new shift in Lf0Hz")  
        op.Type = "ShiftZ" 1wc -v@E  
        op.val1 = taq 6eDIS|/  
        op.parent = parID 6>=>Yj  
        AddOperation eID, op 4nl>&AV  
        Print "Set aqueous humor thickness = " & taq-0.55 E;4Ns  
    @IiT8B  
        '************************************************************************* M2@q{RiS  
        'Radius and conic constant of anterior lens 50DPzn  
        '************************************************************************* 4(aesZ8h  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) K%=n \ Y  
        GetConic eID, entity, curv, conic WQ5sC[&   
    Ab2g),;c  
        SetConic eID, entity, 1/Rant, CCant uAvs  
        Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant H;sQ]:.*]  
    Ve8!   
        '************************************************************************* k@8#Byl|  
        'Radius and conic constant of posterior lens mzT} C&hfP  
        '************************************************************************* k9Sqp :l,  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) (J$A  
        GetConic eID, entity, curv, conic "}OFwes  
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        SetConic eID, entity, 1/Rpost, CCpost Oq[E\8Wn  
        Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost 4|$D.`Wu  
    :):Y6)giBD  
        '************************************************************************* Eq8OAuN  
        'Lens thickness (Position of posterior lens surface) `C*!de]Y%  
        '************************************************************************* $k`8Zx w  
    7 YK+TGmU^  
        parID = FindFullName( "Geometry.Arizona Eye.Lens" ) \4j+pU  
    ]F@md(J  
        ' Delete any z-shift(s) *c AoE l  
        count = 0 (j~V  
        While GetOperationCount(eID)>count YjX=@  
            GetOperation eID, count, op ]JD$fS=_  
            If op.Type="ShiftZ" Then ^mum5j  
                DeleteOperation eID,count 87^ 4",  
                count=count-1 *cf"l  
            End If '.K,EM!-~h  
            count=count+1 %b{!9-n}  
        Wend q9 ;\B&  
    bY2Mw8e%  
        'Set new z-shift !n{c#HfG  
        op.Type = "ShiftZ" gPwp [  
        op.val1 = tlens ?:FotnU*p  
        op.parent = parID JG<3,>@%  
        AddOperation eID, op KB"iF}\P0  
        Print "Set lens thickness = " & tlens AfEEYP)N  
    Lq[wabF  
        '************************************************************************* OV/FQH;V  
        'Lens index of refraction ^97ZH)Ww  
        '************************************************************************* $McO'Bye{h  
        eID = FindMaterial( "Lens" ) 3E ZwF  
        GetModelMaterial eID, mat _B1uE2j9  
    +wUhB\F *  
        mat.Nd = nlens Dy@ \!F  
        SetModelMaterial eID, mat A C^[3  
        Print "Set lens index of refraction = " & nlens rl^LS z  
    8QN8bGxK   
        '************************************************************************* |d5L Ifb(  
        'Pupil diameter (7b_g6>:  
        '************************************************************************* 3kQ^f=Wd  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) e 1loI8  
    %^l&fM*  
        'Adjust pupil diameter (trimming volume inner hole) 4:@|q:DR  
    n`}&, UA$4  
        SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" 5lxq-E3  
    +=h!?<*C8  
        ' Adjust pupil location to just in front of the lens G zXP  
        parID = FindFullName( "Geometry.Arizona Eye" ) #5C3S3e=  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) H ZLOn  
        count = 0 D&r8V;G[[  
        While GetOperationCount(eID)>count )M N yOj  
            GetOperation eID, count, op sOxdq"E  
            If op.Type="ShiftZ" Then m[{&xF|_  
                DeleteOperation eID,count  y:OywIi(  
                count=count-1 Hm* vKFhz  
            End If (A'q@-XQ  
            count=count+1 sYA-FO3gh  
        Wend 1:!rw,Jzl`  
        op.Type = "ShiftZ" \.1b\\  
        op.val1 = taq-0.01 4@e!D Du  
        op.parent = parID ];d:z[\P  
        AddOperation eID, op N#)VD\m  
    ?+O|mX}`-  
        Print "Set pupil diameter = " & pupilDiam LXC`Zq\  
    5SL>q`t.bd  
        'Update AZ Eye subassembly Description I*t)x,~3  
        eID = FindFullName( "Geometry.Arizona Eye" ) >v_5xd9  
        GetEntity eID, entity +Jka:]MW!  
        entity.Description = "Accommodation = " & A & "D" ]XG n2U\  
        SetEntity eID, entity 4D8yb|o  
    DsW`V~ T  
        Update V&oT':%q  
        Print "DONE!" IaTq4rt  
         *@arn Eu  
    End Sub y}-S~Ov>I  
    !J=;Z9  
    如果屈光度是4,光瞳直径是4,则会输出如下数据: !-RpRRR[Co  
    @ KPv&UB  
    Accommodation = 4 Diopters ^1,Eo2yN  
    Pupil Diameter = 4 mm @*"<U]  
    Set aqueous humor thickness = 2.81 <SM&VOiaOz  
    Set anterior lens radius = 10.4 and conic constant = -2.375869 q AVfbcb  
    Set posterior lens radius = -4.424557 and conic constant = -3.081019 g} ~<!VpX  
    Set lens thickness = 3.927 ;k&k#>L!K  
    Set lens index of refraction = 1.42672 (bFWT_CChz  
    Set pupil diameter = 4 ,c7u  
    DONE! EOnp!]Y  
    K aQq[a  
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    QQ:2987619807 l&sO?P[ /  
     
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