切换到宽版
  • 广告投放
  • 稿件投递
  • 繁體中文
    • 1541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 cPunMHD  
    ' _ZiZ4O  
    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。 >E lK8  
    Wdk]>w 'L  
    模型 -A]-o  
    nMM:Tr  
    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。 xQUskjv/  
    2P, %}Ms  
    Table 1. AZ眼睛模型的定义
    >G9YYt~  
    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. m3#rU%Wj  
    t]gZ^5  
    光源 ]C'^&:&<  
    !}lCwV  
    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。 DyPHQ}G  
    N =T 0Td  
    qt{lZ_$  
    图1. 光源和提示信息使用
    ,tTq25~H\  
    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。  ^t}1 $H  
    %fuV]  
    在往下看是内置的脚本用来修改屈光度,使其为4(250mm),光源“Letter F”在视网膜处生成一个字母为F的图像。绿色的光线聚焦的非常好而红色和蓝色光线有一点的模糊。使用Positions Spot Diagram分析工具来观察最为合适。 o' EJ,8  
    -kk0zg &|i  
    图2. 字母F光源的设定方法光 jhR`%aH4  
    +7 \"^D  
    图3. 字母F在视网膜上位置点列图
    +-r ~-bs  
    视网膜的散射 Uee(1  
    f/95}6M  
    在散射文件中,有一个名为“Retina surface”的72%的反射型朗伯散射,它为视网膜的散射提供了一个粗略的近似。为了模拟来自视网膜的散射,改变自定义元件“Eye ball” 下的视网膜的表面从“halt all” 到”Allow All”。并使几何中“plane”可追迹。 #_SsSD=.Sy  
    ?ESsma6  
    b^:frjaE3  
    图4. 视网膜朗伯散射设定
    k*4!rWr0r&  
    注意在视网膜的表面有散射重点采样规格定义,在“Scatter”标签的底部可获取该信息。“toward pupil”指定散射光朝向光瞳,半角度10度。 DuQW?9^232  
    3ncN) E/@  
    XjXz#0nR  
    图5. 视网膜重点采样规格设定
    7!F -.kG  
    脚本 D wfw|h  
    V_3K((P6  
    内置脚本使用对话框显示屈光度和光瞳直径的数值设置。使用FRED Basic脚本创建和使用对话框非常容易。图6显示了如何获取用户自定义对话框,如下图所示: (nu;o!mo9  
    D_q"|D$SB  
    图6. 用户对话框的创建与编辑
    T@jv0/(+  
    图7. 用户对话框编辑器
    _]v@Dq VP  
    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。 Hp>_:2O8s  
    余下的脚本计算与屈光度有关的所有参数。 %(1Jt "9|  
    6]r#6c %  
    分析 kGmz1S}2  
    S3UJ)@ E  
    屈光度为4,光瞳直径为4mm,字母F点在视网膜上所成的像。 Xhs*nt%l  
    dsU'UG7L  
    图7. 字母F在视网膜上颜色分析
    I@oSRB  
    脚本代码 8 =oUE$9  
    <v6W l\  
    Option Explicit     'Remove this to enable non-dimensioned variables to be used. EQtYb"_  
    ?bAv{1dvT=  
    Dim entity As T_ENTITY _lDNYpv  
    Dim op As T_OPERATION K&VMhMVb  
    Dim mat As T_MODELMATERIAL =w!2R QB  
    Dim A As Double !k Heslvi  
    Dim pupilDiam As Double :K~sazs7J  
    Dim eID As Long 9m.MGJbQ_f  
    Dim parID As Long &+0?Xip{Z  
    Dim count As Integer e3mFO+  
    Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double #-i#mbZ e  
    Dim tlens As Double, nlens As Double 6p9 { z42  
    Dim curv As Double, conic As Double 6 w'))Z  
    Dim ok As Long K$l@0r ~k  
    mp)+wZAN&  
    Sub Main ;X;(7  
    OZ33w-X<  
        '用户输入对话框 U[?f@.&  
        Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 d}y")q|F  
            TextBox 220,21,40,21,.TextBox1 'default: 0 o%!s/Z1  
            Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 Z~w2m6;s  
            OKButton 40,91,90,21 g[*"LOw  
            CancelButton 190,91,90,21 <#wVQ\0C  
            Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 zGdYk-H3TH  
            TextBox 220,49,40,21,.TextBox2 'default: 4 0(>3L:  
        End Dialog h=qT@)h1>  
        Dim dlg As UserDialog 6L;]5)#  
    &>!-67  
        ok = Dialog (dlg) b0/YX@  
    ~0h@p4  
        If ok=0 Then    'cancel button was pressed *+XiBho  
            Print "Execution cancelled." n.i 8?:  
            End m[z $y  
        End If +v~x_E5FP  
    qyAnq%B}  
        'Assign accommodation and pupil diameter & use defaults if field left empty a`8]TD  
        If dlg.TextBox1 = "" Then ;%Px~g  
            A = 0           'Default accommodation dz^b(q  
        Else 9)8Cf% <(  
            A = CDbl(dlg.TextBox1) !9{UBAh  
        End If Z- t&AH  
    bT6VxbNS  
        If dlg.TextBox2 = "" Then 9|3sNFGX  
            pupilDiam = 4   'Default pupil diameter d"@ /{O^1  
        Else {kBsiSvsA;  
            pupilDiam = CDbl(dlg.TextBox2) tJ7F.}\;C  
        End If `!spi=f  
    VR .t  
        Print " " 4AKr.a0q  
        Print "Accommodation = " & A & " Diopters" 5F!Qn\{u{  
        Print "Pupil Diameter = " & pupilDiam & " mm" w3 kkam"  
    R(*t 1R\  
        ' Calculate new parameters with accommodation 1Q!kk5jE  
        taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness lT*@f39~g  
    rHM^_sYRb  
        Rant = 12.0 - 0.4*A                     'Radius of anterior lens MV??S{^4  
        CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens Qwt0~9n(  
    fL# r@TB-s  
        Rpost = -5.224557 + 0.2*A               'Radius of posterior lens b;{"@b,Y  
        CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens :<mJRsDf  
    xticC>  
        tlens = 3.767 + 0.04*A                  'Lens thickness q)f_!N  
    4lWqQVx  
        nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction :p,|6~b$  
    V0rQtxE{F  
        'Adjust parameters to account for accommodation I 44]W&  
    {%CW!Rc  
        '************************************************************************* (~%NRH<\  
        'Aqueous thickness (Position of Lens) h _{f_GQ"  
        '************************************************************************* wJ pb$;  
        eID = FindFullName( "Geometry.Arizona Eye.Lens" ) 6^t#sEff]  
        GetCustomElement eID, entity IC5QH<.$C  
    nu7 R  
        parID = FindFullName( "Geometry.Arizona Eye" ) [^?i<z{0C  
    4H (8BNgzV  
        ' Delete any shift(s) in z jpO0dtn3=  
        count = 0 j}tM0Ug.U  
        While GetOperationCount(eID)>count IG# wY  
            GetOperation eID, count, op hRRxOr#*$  
            If op.Type="ShiftZ" Then 1 z~|SmP1  
                DeleteOperation eID,count 7K "1^  
                count=count-1 Lui6;NY  
            End If UWEegFq*  
            count=count+1 AT+ l%%   
        Wend deArH5&!  
    Z5n-3h!+ED  
        'Set new shift in 4r `I)  
        op.Type = "ShiftZ" s+v9H10R  
        op.val1 = taq VBQAkl?(}4  
        op.parent = parID Xz^k.4 Y{4  
        AddOperation eID, op -(F} =o'  
        Print "Set aqueous humor thickness = " & taq-0.55 Q,JH/X  
    E0Q6Ryn  
        '************************************************************************* 8b.k*,r>  
        'Radius and conic constant of anterior lens }nX0h6+1  
        '************************************************************************* #h^nvRmON  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) R.*;] R>M  
        GetConic eID, entity, curv, conic |'1.a jxw  
    Z^2SG_pD  
        SetConic eID, entity, 1/Rant, CCant B* mZxY1  
        Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant LdH1sHy*d`  
    Jw@X5-(Cp  
        '************************************************************************* :e=7=|@7  
        'Radius and conic constant of posterior lens ULxQyY;32  
        '************************************************************************* !L{mE&  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) |9%~z0  
        GetConic eID, entity, curv, conic f.uuXK  
    ?wPTe^Qtv  
        SetConic eID, entity, 1/Rpost, CCpost p<H_]|7$7U  
        Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost i KQj[%O  
    Pe,ky>ow  
        '************************************************************************* \ t1#5  
        'Lens thickness (Position of posterior lens surface) H390<`  
        '************************************************************************* (kB  
    AV2Jl"1)z  
        parID = FindFullName( "Geometry.Arizona Eye.Lens" ) h6?^rS8U  
    ~EY)c~ H  
        ' Delete any z-shift(s) %;ED} X  
        count = 0 " Ot%{&:2  
        While GetOperationCount(eID)>count G gA:;f46  
            GetOperation eID, count, op %;h1n6=v2  
            If op.Type="ShiftZ" Then >QvqH 2  
                DeleteOperation eID,count ;Us6:}s  
                count=count-1 o.NU"$\?  
            End If ]:D&kTc  
            count=count+1 0.wF2!V.  
        Wend #K:iB*  
    jd ;)8^7K  
        'Set new z-shift SF*mY=1  
        op.Type = "ShiftZ" [[^r;XKQ  
        op.val1 = tlens hNZ_= <D!  
        op.parent = parID /nA>ox78  
        AddOperation eID, op g]HWaFjc5  
        Print "Set lens thickness = " & tlens USN'-Ah  
    \mGb|aF8  
        '************************************************************************* q`{@@[/ (y  
        'Lens index of refraction XchD3p+uB  
        '************************************************************************* xjU0&  
        eID = FindMaterial( "Lens" ) sj&(O@~R  
        GetModelMaterial eID, mat ]kmAN65c  
    *!y04'p`<  
        mat.Nd = nlens _ymSo`Iv R  
        SetModelMaterial eID, mat  +qj Z;5(  
        Print "Set lens index of refraction = " & nlens eWm'eO  
    y~#5!:Be  
        '************************************************************************* sq#C|v/  
        'Pupil diameter 85io %>&0  
        '************************************************************************* uGXvP(Pg'  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) hl**G4z9q  
    J+ :3== ,  
        'Adjust pupil diameter (trimming volume inner hole) 6zU0 8z0-  
    0K.$C~ C  
        SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" {`2 0'  
    :/=P6b;  
        ' Adjust pupil location to just in front of the lens [7DU0Xg7  
        parID = FindFullName( "Geometry.Arizona Eye" ) $<Gt^3e  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) Th%w-19,8  
        count = 0 adoK-bSt  
        While GetOperationCount(eID)>count '!Va9m*w7  
            GetOperation eID, count, op Om:Gun\%  
            If op.Type="ShiftZ" Then L!33`xef'  
                DeleteOperation eID,count aMydeTCHi  
                count=count-1 ^8oN~HLZ  
            End If ZU B]qzmK  
            count=count+1 *B&i`tq  
        Wend Y(rQ032s  
        op.Type = "ShiftZ" jK6dI 7h  
        op.val1 = taq-0.01 rM~Mqpk  
        op.parent = parID :+_H%4+  
        AddOperation eID, op M-QQ  
    :X9;KoJl-V  
        Print "Set pupil diameter = " & pupilDiam <]S M$) =D  
    E]a,2{&8<  
        'Update AZ Eye subassembly Description <MhODC")  
        eID = FindFullName( "Geometry.Arizona Eye" ) C&d,|e "\  
        GetEntity eID, entity T^|6{ S\  
        entity.Description = "Accommodation = " & A & "D" Q"pZPpl&  
        SetEntity eID, entity ri"=)]  
     5 YIk  
        Update 6S%KUFB+e  
        Print "DONE!" 65 &+Fv  
         p'/%"  
    End Sub #CeWk$)m  
    S,+|A)\#  
    如果屈光度是4,光瞳直径是4,则会输出如下数据: 0_>1CW+X  
    $dt* 4n'  
    Accommodation = 4 Diopters 6 ;\>,  
    Pupil Diameter = 4 mm "el3mloR 8  
    Set aqueous humor thickness = 2.81 sV~|9/r  
    Set anterior lens radius = 10.4 and conic constant = -2.375869 ) { "}bMf  
    Set posterior lens radius = -4.424557 and conic constant = -3.081019 "NSY=)fV  
    Set lens thickness = 3.927 `kOp9(Q{  
    Set lens index of refraction = 1.42672 &s.-p_4w^D  
    Set pupil diameter = 4 bb/A}< zD  
    DONE! MGKSaP;x  
    QA!'p1{#  
    ![%:X)?  
    QQ:2987619807 1@]gBv<  
     
    分享到