切换到宽版
  • 广告投放
  • 稿件投递
  • 繁體中文
    • 1982阅读
    • 0回复

    [技术]Arizona眼睛模型 [复制链接]

    上一主题 下一主题
    离线infotek
     
    发帖
    6441
    光币
    26350
    光券
    0
    只看楼主 倒序阅读 楼主  发表于: 2021-10-22
    简介 o6$4/I  
    V^;jJ']  
    人眼光学模型可用来设计眼科用设备,光学系统注定了要与人眼一起使用。本文演示了这样一个模型:Arizona眼睛模型,在Jim Schwiegerling教授的书中有详细描述:《Field Guide to Visual and Ophthalmic Optics》。AZ眼睛模型达到了基于平均临床数据所决定的轴上和轴外像差等级。FRED文件包含了此眼睛模型及几个用来分析它的光源,并包括一个基于想要的屈光度来调整模型的内嵌脚本。 Bj7gQ%>H4  
    %D *OO{  
    模型 5h;+Ky!I  
    7 [0L9\xm  
    模型的定义如表1种所示,由半径、圆锥常数、折射率、阿贝数、到下一面的距离等一系列表面组成。一些参数由屈光度(A)来决定。 ;J7F J3n  
    0Fu~%~#E$  
    Table 1. AZ眼睛模型的定义
    tJN<PCG6"  
    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. .9.2Be  
     W%\C_  
    光源 av~5l4YL  
    (y^vqMz  
    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。 %j7XEh<'  
    f5` g  
    K$d$m <  
    图1. 光源和提示信息使用
    n0is\ZK 0  
    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。 'F3)9&M  
    %iw3oh&Fkm  
    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。 7F'`CleU  
    iTaWup  
    图2. 字母F光源的设定方法光 =G]@+e  
    jmeRrnC}  
    图3. 字母F在视网膜上位置点列图
    yq$,,#XDD=  
    视网膜的散射 fum0>tff  
    ?Q&yEGm(  
    在散射文件中,有一个名为“Retina surface”的72%的反射型朗伯散射,它为视网膜的散射提供了一个粗略的近似。为了模拟来自视网膜的散射,改变自定义元件“Eye ball” 下的视网膜的表面从“halt all” 到”Allow All”。并使几何中“plane”可追迹。 7 x<i :x3  
    P~ &$l2  
    Ps<d('=  
    图4. 视网膜朗伯散射设定
    k!{p7*0  
    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。 k?7 X3/O  
    +zs4a96[  
    ,UuH}E  
    图5. 视网膜重点采样规格设定
    r hfb ftw  
    脚本 ccL~#c0P7  
    ZWS`\M  
    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: {%C7EAq*  
    LcE+GC  
    图6. 用户对话框的创建与编辑
    7hcNf,  
    图7. 用户对话框编辑器
    0P]E6hWgg  
    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。 PsZ >P|e1  
    余下的脚本计算与屈光度有关的所有参数。 3g6j?yYqb  
    L{c q, jk  
    分析 y\x+  
    J4\qEO  
    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/Te)  
    `HBf&Z  
    图7. 字母F在视网膜上颜色分析
    xL" |)A =  
    脚本代码 =yy5D$\  
    \W`w` o  
    Option Explicit     'Remove this to enable non-dimensioned variables to be used. b3VS\[p  
    C/-63O_  
    Dim entity As T_ENTITY l\n@cQR  
    Dim op As T_OPERATION hh[jN 7K  
    Dim mat As T_MODELMATERIAL k]I0o)+O.  
    Dim A As Double wT{nu[=GH*  
    Dim pupilDiam As Double 5v6Ei i:  
    Dim eID As Long y.Z?LCd<  
    Dim parID As Long n-@j5w+k4  
    Dim count As Integer o-Ga3i 8  
    Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double NG6& :4!  
    Dim tlens As Double, nlens As Double Q6r7.pk"SU  
    Dim curv As Double, conic As Double RG4sQ0  
    Dim ok As Long L~KM=[cn  
    |.3DD"*  
    Sub Main _x5 3g A  
    jfqopiSi  
        '用户输入对话框 W='> :H  
        Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 lMbAs.!  
            TextBox 220,21,40,21,.TextBox1 'default: 0 f^.AD-  
            Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 ::/j$bL  
            OKButton 40,91,90,21 k Zq!&  
            CancelButton 190,91,90,21 2TA*m{\Hr  
            Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 /ID?DtJ  
            TextBox 220,49,40,21,.TextBox2 'default: 4 %p 0xM  
        End Dialog v 7x:dcV  
        Dim dlg As UserDialog x UD-iSY  
    Vkc#7W(  
        ok = Dialog (dlg) PKzyV ;  
    *C:|X b<9  
        If ok=0 Then    'cancel button was pressed 2Roc|)-47  
            Print "Execution cancelled." }O4^Cc6  
            End TG5XSy  
        End If .>IhN 5  
    aUtnR<6  
        'Assign accommodation and pupil diameter & use defaults if field left empty ,kn"> k9  
        If dlg.TextBox1 = "" Then Ez-[ )44/  
            A = 0           'Default accommodation .uk>QM s1  
        Else 4tS.G  
            A = CDbl(dlg.TextBox1) =>! Y{: y(  
        End If I}vmU^Y>  
    : 7`[$<~E  
        If dlg.TextBox2 = "" Then BV[5}  
            pupilDiam = 4   'Default pupil diameter B[4KX  
        Else =Yt R`  
            pupilDiam = CDbl(dlg.TextBox2) ]V#M%0:Q82  
        End If [n$BRk|  
    heK7pH7;d  
        Print " " i|m3mcI%2  
        Print "Accommodation = " & A & " Diopters" iS<I0\D  
        Print "Pupil Diameter = " & pupilDiam & " mm" 5x>}O3Q_  
    KPj\-g'A  
        ' Calculate new parameters with accommodation \9g+^vQg  
        taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness jE/AA!DC#  
     pn5Q5xc  
        Rant = 12.0 - 0.4*A                     'Radius of anterior lens wD]/{ jw  
        CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens i0$kit  
    8Bjib&im  
        Rpost = -5.224557 + 0.2*A               'Radius of posterior lens CLJ;<  
        CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens Ch3jxgQY  
    k|H:  
        tlens = 3.767 + 0.04*A                  'Lens thickness Yn G_m]  
    :d#VE-e  
        nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction ]f({`&K5  
    LMAE)]N  
        'Adjust parameters to account for accommodation >\Ww;1yV  
    ikSt"}/hd  
        '************************************************************************* ]@Uq=?%  
        'Aqueous thickness (Position of Lens) A'&K/)Z  
        '************************************************************************* HEM9E&rL  
        eID = FindFullName( "Geometry.Arizona Eye.Lens" ) aiu5}%U  
        GetCustomElement eID, entity E`uY1B[c  
    hK,Sf ;5V  
        parID = FindFullName( "Geometry.Arizona Eye" ) _c_[ C*T]  
    _`:1M2=  
        ' Delete any shift(s) in z ]h %Wiw  
        count = 0 PIwFF}<(  
        While GetOperationCount(eID)>count AGYc |;  
            GetOperation eID, count, op &H`jL4S  
            If op.Type="ShiftZ" Then "pRtczxOgR  
                DeleteOperation eID,count D5*q7A6  
                count=count-1 -3=#u_  
            End If c:o]d)S  
            count=count+1 !*%WuyCgr4  
        Wend F6{bjv2A  
    >)M`IU[d^.  
        'Set new shift in n74V|b6W  
        op.Type = "ShiftZ" v63"^%LX  
        op.val1 = taq Qh'ATo  
        op.parent = parID ;k>&FWEG  
        AddOperation eID, op m1M t#@,$  
        Print "Set aqueous humor thickness = " & taq-0.55 @3C>BLI8+  
    wlqpn(XR  
        '************************************************************************* GfmI<{da  
        'Radius and conic constant of anterior lens 7B\Vs-d  
        '************************************************************************* .Lsavpo  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) =aBctd:eX`  
        GetConic eID, entity, curv, conic NP/Gn6fr  
    n4R(.N00  
        SetConic eID, entity, 1/Rant, CCant UZJCvfi  
        Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant &N\jG373  
    ~ijVmWNk  
        '************************************************************************* Xy$3VU*  
        'Radius and conic constant of posterior lens li}1S  
        '************************************************************************* )E-inHD /  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) 9{5&^RbCp  
        GetConic eID, entity, curv, conic 2;DuHO1  
    C8V/UbA /  
        SetConic eID, entity, 1/Rpost, CCpost |6K+E6H  
        Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost @c;|G$E@3  
    #0P$M!%  
        '************************************************************************* YW( Qmo7  
        'Lens thickness (Position of posterior lens surface) V`XNDNJ:  
        '************************************************************************* e'~J,(fB  
    P;qN(2L/=<  
        parID = FindFullName( "Geometry.Arizona Eye.Lens" ) eOs)_?}  
    lE&&_INHQ  
        ' Delete any z-shift(s) 6sx'S?Qa*  
        count = 0 d\R,Q  
        While GetOperationCount(eID)>count { + Zd*)M[  
            GetOperation eID, count, op S/e2P|}  
            If op.Type="ShiftZ" Then "J [K 3  
                DeleteOperation eID,count j/f?"VEr  
                count=count-1 ?&63#B,iZ  
            End If j/_ s"}m{  
            count=count+1 jU9$Ehg I  
        Wend -y8`yHb_  
    _lGdUt 2  
        'Set new z-shift VFURAYS  
        op.Type = "ShiftZ" V9{]OV%  
        op.val1 = tlens Kgi<UkFP  
        op.parent = parID +#lM  
        AddOperation eID, op $Bs {u=+w  
        Print "Set lens thickness = " & tlens iw8yb;|z;A  
    LSGBq  
        '************************************************************************* ,y 2$cO_>  
        'Lens index of refraction i]6`LqlO  
        '************************************************************************* P3)Nl^/  
        eID = FindMaterial( "Lens" ) iS WU'K  
        GetModelMaterial eID, mat #><.oreXq  
    ]+XYEv  
        mat.Nd = nlens &U5{Hm9Ynr  
        SetModelMaterial eID, mat QgU8 s'e  
        Print "Set lens index of refraction = " & nlens %S*{9hm/  
    zMm#Rhn  
        '************************************************************************* :y%/u%L  
        'Pupil diameter Q@<S[Qh[.  
        '************************************************************************* @|63K)Xy  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) $JJrSwR<h  
    f78An 8  
        'Adjust pupil diameter (trimming volume inner hole) jr /pj?  
    q_g+Jf P-D  
        SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" Y2ZT.l  
    pb ~u E  
        ' Adjust pupil location to just in front of the lens b F"G[pD  
        parID = FindFullName( "Geometry.Arizona Eye" ) w$z}r  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) UEM(@zD]  
        count = 0 #LL?IRH9^  
        While GetOperationCount(eID)>count Mc09ES  
            GetOperation eID, count, op %l}D.ml  
            If op.Type="ShiftZ" Then /%}*Xh  
                DeleteOperation eID,count JEahGzO  
                count=count-1 b&~4t/Vq  
            End If `\gnl'  
            count=count+1 l_P-j 96WD  
        Wend #fM#p+v  
        op.Type = "ShiftZ" \?0&0;5  
        op.val1 = taq-0.01 / ';0H_  
        op.parent = parID ypKUkH/  
        AddOperation eID, op 6y+Kjd/D  
    544X1Ww2  
        Print "Set pupil diameter = " & pupilDiam 7\$qFF-y  
    )}D'<^=#T  
        'Update AZ Eye subassembly Description ysxb?6  
        eID = FindFullName( "Geometry.Arizona Eye" ) V5sg#|&  
        GetEntity eID, entity %k-3?%&8  
        entity.Description = "Accommodation = " & A & "D" \O*-#}~\  
        SetEntity eID, entity Zhh2v>QOy  
    \r /ya<5  
        Update ~P8tUhffK  
        Print "DONE!" ewa wL"  
         Szq/hv=Q  
    End Sub s \;"X  
    4wa`<H&S5  
    如果屈光度是4,光瞳直径是4,则会输出如下数据: yj;sSRT  
    J&[@}$N  
    Accommodation = 4 Diopters !MYSfPdS  
    Pupil Diameter = 4 mm cC=[Saatsf  
    Set aqueous humor thickness = 2.81 A+SE91m  
    Set anterior lens radius = 10.4 and conic constant = -2.375869 'Jt]7;04p  
    Set posterior lens radius = -4.424557 and conic constant = -3.081019 tZ=E')!\  
    Set lens thickness = 3.927 Gn|F`F  
    Set lens index of refraction = 1.42672 uD1e!oU  
    Set pupil diameter = 4 4L ;% h  
    DONE! +Z7th7W/,  
     
    分享到