切换到宽版
  • 广告投放
  • 稿件投递
  • 繁體中文
    • 1542阅读
    • 0回复

    [分享]Arizona眼睛模型 [复制链接]

    上一主题 下一主题
    离线infotek
     
    发帖
    6429
    光币
    26290
    光券
    0
    只看楼主 倒序阅读 楼主  发表于: 2020-12-09
    简介 n!y}p q6  
    ? 8)$N  
    人眼光学模型可用来设计眼科用设备,光学系统注定了要与人眼一起使用。本文演示了这样一个模型:Arizona眼睛模型,在Jim Schwiegerling教授的书中有详细描述:《Field Guide to Visual and Ophthalmic Optics》。AZ眼睛模型达到了基于平均临床数据所决定的轴上和轴外像差等级。FRED文件包含了此眼睛模型及几个用来分析它的光源,并包括一个基于想要的屈光度来调整模型的内嵌脚本。 n0kkUc-`   
    CI,xp  
    模型 }sS1 p6z  
    g].hL  
    模型的定义如表1种所示,由半径、圆锥常数、折射率、阿贝数、到下一面的距离等一系列表面组成。一些参数由屈光度(A)来决定。 AkR ZUj\  
    Voc&T+A m  
    Table 1. AZ眼睛模型的定义
    Zu%oIk  
    在FRED中使用0屈光度来创建的,光瞳加在了透镜的前面。材料是创建一个新的材料并选择类型“Model Material”,输入的参数是nd和vd. J*O$)K%Hx  
    ,<?M/'4}G  
    光源 X+XbIbUuL  
    F`YxH*tO7  
    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。 Fgg4QF  
    L\asrdL?=  
    x+5y287#  
    图1. 光源和提示信息使用
    quw:4W>  
    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。 -2Azpeh  
    s *1%I$=@  
    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。 B 9AE*  
    $U/_8^6B0  
    图2. 字母F光源的设定方法光 \ g[A{  
    Nm/Fc   
    图3. 字母F在视网膜上位置点列图
    Vl+,OBy  
    视网膜的散射 |1(9_=i'  
    Gk5SG_o  
    在散射文件中,有一个名为“Retina surface”的72%的反射型朗伯散射,它为视网膜的散射提供了一个粗略的近似。为了模拟来自视网膜的散射,改变自定义元件“Eye ball” 下的视网膜的表面从“halt all” 到”Allow All”。并使几何中“plane”可追迹。 )z?Kq0  
    ;]^JUmxU[d  
    >w=xGb7  
    图4. 视网膜朗伯散射设定
    I3V>VLv  
    注意在视网膜的表面有散射重点采样规格定义,在“Scatter”标签的底部可获取该信息。“toward pupil”指定散射光朝向光瞳,半角度10度。 #`H^8/!e  
    ~cEr <mzR  
    h/%Hk;|9  
    图5. 视网膜重点采样规格设定
    '%"#]  
    脚本 3 e9fziQ~  
    7eg//mL"6  
    内置脚本使用对话框显示屈光度和光瞳直径的数值设置。使用FRED Basic脚本创建和使用对话框非常容易。图6显示了如何获取用户自定义对话框,如下图所示: 2=l !b/m  
    n`hes_{,g  
    图6. 用户对话框的创建与编辑
    (_lc< Bj  
    图7. 用户对话框编辑器
    XOy#? X/`  
    如果“OK”按钮按下,将会核对对话框下面的代码行,如果点击取消则脚本终止。然后输入的参数赋予变量,如果此处是保留为空白,则使用默认值。因此,如果没有值输入并点击“OK”按钮,则脚本是以屈光度为0,光瞳直径为4mm来运行的。 ?RD)a`y51  
    余下的脚本计算与屈光度有关的所有参数。 QYL ';  
    %7?v='s=  
    分析 (8(z42  
    3It'!R8$  
    屈光度为4,光瞳直径为4mm,字母F点在视网膜上所成的像。 }`9}Q O  
    +<ey Iw  
    图7. 字母F在视网膜上颜色分析
    lFY;O !Y5\  
    脚本代码 :I}_  
    U q6..<#  
    Option Explicit     'Remove this to enable non-dimensioned variables to be used. :Y[r^=>  
    VmB/X))   
    Dim entity As T_ENTITY +6{KrREX)  
    Dim op As T_OPERATION T<0Bq"'%  
    Dim mat As T_MODELMATERIAL K9*#H(  
    Dim A As Double (Rk g  
    Dim pupilDiam As Double FB PT@`~v  
    Dim eID As Long !2N#H~{  
    Dim parID As Long ca_8S8lv  
    Dim count As Integer #| 8!0]n'  
    Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double ;.h5; `&  
    Dim tlens As Double, nlens As Double 3;`93TO{  
    Dim curv As Double, conic As Double `#X{.  
    Dim ok As Long hGF(E*  
    kc8T@5+I0  
    Sub Main XI,F^K  
    &w3LMOT  
        '用户输入对话框 P"u*bqk  
        Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 JCZJ\f*EZ  
            TextBox 220,21,40,21,.TextBox1 'default: 0 p$@=N6)I.k  
            Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 6#5@d^a  
            OKButton 40,91,90,21 [:!#F7O-  
            CancelButton 190,91,90,21 |P2GL3NR  
            Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 r/L3j0  
            TextBox 220,49,40,21,.TextBox2 'default: 4 b\?#O}  
        End Dialog $(}kau  
        Dim dlg As UserDialog );;UNO21+  
    7w{`f)~  
        ok = Dialog (dlg) vVLR9"rHM  
    $zz=>BOk  
        If ok=0 Then    'cancel button was pressed -ij1%#tz  
            Print "Execution cancelled." )11/BB\v  
            End :"O=/p+*Us  
        End If ,^o^@SI)   
    {M E|7TS=  
        'Assign accommodation and pupil diameter & use defaults if field left empty bTHa;* `  
        If dlg.TextBox1 = "" Then aM.l+D P  
            A = 0           'Default accommodation qg6Hk:^r  
        Else XW]|Mv[M  
            A = CDbl(dlg.TextBox1) uD:O[H-x  
        End If HA"dw2 |  
    ~rY<y%K  
        If dlg.TextBox2 = "" Then ~5}b$qL#`  
            pupilDiam = 4   'Default pupil diameter +I\ bs.84  
        Else W.:k E|a.g  
            pupilDiam = CDbl(dlg.TextBox2) i$:CGUb  
        End If ZVIBmx  
    .#WF'  
        Print " " T*h+"TmE  
        Print "Accommodation = " & A & " Diopters" |klL KX&  
        Print "Pupil Diameter = " & pupilDiam & " mm" 7@tr^JykO  
    >Q5E0 !]  
        ' Calculate new parameters with accommodation l/rhA6kEU  
        taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness /'VCJjzZ  
    ]\ r~"*TZ  
        Rant = 12.0 - 0.4*A                     'Radius of anterior lens Z/x<U.B  
        CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens `O}. .N]g  
    F/EHU?_EI  
        Rpost = -5.224557 + 0.2*A               'Radius of posterior lens "l +Jx|h\  
        CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens p6}jCGJ  
    _9 Gy`  
        tlens = 3.767 + 0.04*A                  'Lens thickness KI>7h.t  
    PL+fLCk,I  
        nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction J;T_ 9  
    c@nl;u)n  
        'Adjust parameters to account for accommodation )If[pw@j  
    s:]rL&|  
        '************************************************************************* @fE^w^K7  
        'Aqueous thickness (Position of Lens) [Q 2t,tQx  
        '************************************************************************* eIqj7UY_  
        eID = FindFullName( "Geometry.Arizona Eye.Lens" ) /CA)R26G  
        GetCustomElement eID, entity {&h&:  
    @Qc['V)  
        parID = FindFullName( "Geometry.Arizona Eye" ) >2g CM  
    0|^x[dh  
        ' Delete any shift(s) in z :Dr& {3>  
        count = 0 ^~`8 - TE  
        While GetOperationCount(eID)>count 7L-%5:1%  
            GetOperation eID, count, op i*U\~CZjT  
            If op.Type="ShiftZ" Then 10}Zoq|)n  
                DeleteOperation eID,count ` chf8  
                count=count-1 XIp9=jhSR  
            End If [#9ij3vxd  
            count=count+1 "!Qhk3*  
        Wend *V"cu  
    ~l}TlRqL  
        'Set new shift in |y:DLsom?i  
        op.Type = "ShiftZ" RD_;us@&&*  
        op.val1 = taq O5=ggG  
        op.parent = parID 9lD,aOb  
        AddOperation eID, op G8;S`-D1a,  
        Print "Set aqueous humor thickness = " & taq-0.55 o"]eAQ  
    n~)Y%xe[U  
        '************************************************************************* )$]+R?v  
        'Radius and conic constant of anterior lens HRb_ZJz  
        '************************************************************************* 5r+0^UAO:J  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) hr{%'DAS  
        GetConic eID, entity, curv, conic Maa.>2v<  
    ?xf;#J+{8  
        SetConic eID, entity, 1/Rant, CCant _$bx4a  
        Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant Sm Ei _u]'  
    h ?ia4t  
        '************************************************************************* #/tdZ0  
        'Radius and conic constant of posterior lens :,ym)|YV  
        '************************************************************************* yav)mO~QU6  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) =)zq %d?i;  
        GetConic eID, entity, curv, conic bL&]3n9Rwu  
    Cir =(  
        SetConic eID, entity, 1/Rpost, CCpost DS$ _"'g%i  
        Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost .gPsJ?b  
    18n84RkI9  
        '************************************************************************* iP!Y4F  
        'Lens thickness (Position of posterior lens surface) t~a$|( 9  
        '************************************************************************* ZK ?x_`w  
    {&<}*4D  
        parID = FindFullName( "Geometry.Arizona Eye.Lens" ) NuooA  
    ILO+=xU  
        ' Delete any z-shift(s) )R +o8C  
        count = 0 2?r8>#_*  
        While GetOperationCount(eID)>count xXx`a\i  
            GetOperation eID, count, op - dOT/%Ux  
            If op.Type="ShiftZ" Then hv"toszj\  
                DeleteOperation eID,count GY",AL8f  
                count=count-1 )4`Ml*7x  
            End If 3H%HJS  
            count=count+1 jF3!}*7,  
        Wend (O-)uC  
    Vd/S81/  
        'Set new z-shift (En\odbvt  
        op.Type = "ShiftZ" |O)deiJRy  
        op.val1 = tlens y[zA [H:  
        op.parent = parID a?Y1G3U'  
        AddOperation eID, op `;_tt_  
        Print "Set lens thickness = " & tlens @*uX[)  
    OhW=F2OIV  
        '************************************************************************* n>E*g|a  
        'Lens index of refraction 'iVo,m[yKU  
        '************************************************************************* `Of wl%G  
        eID = FindMaterial( "Lens" ) 0`P]fL+&  
        GetModelMaterial eID, mat r~}}o o4K  
    %)/f; T6  
        mat.Nd = nlens Ij #a  
        SetModelMaterial eID, mat _M&.kha  
        Print "Set lens index of refraction = " & nlens `es($7}P_W  
    O|>1~^w  
        '************************************************************************* |x6mkSf]ke  
        'Pupil diameter #8z,'~\  
        '************************************************************************* 2 &Byq  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) UTTC:=F+  
    bS<@Rd{g  
        'Adjust pupil diameter (trimming volume inner hole) Lm wh`oOl  
    |wJZU  
        SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" [)3 U])w/  
    P*PL6UQ  
        ' Adjust pupil location to just in front of the lens aVP|:OAj  
        parID = FindFullName( "Geometry.Arizona Eye" ) eCp|QSXE  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) fl"y@;;#h  
        count = 0 >-w=7,?'?z  
        While GetOperationCount(eID)>count UPKi/)C;  
            GetOperation eID, count, op lkfFAwnc  
            If op.Type="ShiftZ" Then |nEV Oy>'  
                DeleteOperation eID,count ^2r}_ AX  
                count=count-1 ?nZ <?  
            End If '%EZoc/U  
            count=count+1 Uxemlp%%*  
        Wend S/-7Zo&w+  
        op.Type = "ShiftZ" j#e.rNG  
        op.val1 = taq-0.01 be:phS4vz  
        op.parent = parID 5(|M["KK~  
        AddOperation eID, op ^V}R(gDu}s  
    Z02s(y=k1  
        Print "Set pupil diameter = " & pupilDiam T'M66kg  
    DnHAm q]  
        'Update AZ Eye subassembly Description q.MVF]  
        eID = FindFullName( "Geometry.Arizona Eye" ) yb{Q,Dz  
        GetEntity eID, entity O4/n!HOb  
        entity.Description = "Accommodation = " & A & "D" B#aH\$_U  
        SetEntity eID, entity {TncqA  
    8A:^K:Q  
        Update bV`C;RPn  
        Print "DONE!" q{GSsDo-:V  
         sJb)HQ,7x  
    End Sub ZCBPO~&hO'  
    Iv(Qa6(  
    如果屈光度是4,光瞳直径是4,则会输出如下数据: fT3*>^Uv  
    !&`\ LJ=j  
    Accommodation = 4 Diopters y5/6nvH_6  
    Pupil Diameter = 4 mm |WAD $3  
    Set aqueous humor thickness = 2.81 `.'i V[fr  
    Set anterior lens radius = 10.4 and conic constant = -2.375869 yvz?4m"_yB  
    Set posterior lens radius = -4.424557 and conic constant = -3.081019 3l%,D: ?  
    Set lens thickness = 3.927 oM<!I0"gC+  
    Set lens index of refraction = 1.42672 v (ka,Dk3  
    Set pupil diameter = 4 0i\',h}9  
    DONE! ufCqvv>'  
    rAx"~l.=  
    ns#~}2"d  
    QQ:2987619807 gKN}Of@^1  
     
    分享到