切换到宽版
  • 广告投放
  • 稿件投递
  • 繁體中文
    • 1782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
    6374
    光币
    26015
    光券
    0
    只看楼主 倒序阅读 楼主  发表于: 2021-10-22
    简介 PglSQ2P  
    l k sNy  
    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。 ;J@U){R  
    $`A{-0=x\U  
    模型 ;A G&QdTMh  
    2tb+3K1  
    模型的定义如表1种所示,由半径、圆锥常数、折射率、阿贝数、到下一面的距离等一系列表面组成。一些参数由屈光度(A)来决定。 vbD""  
    sYq:2Wn>8Q  
    Table 1. AZ眼睛模型的定义
    hgj ]Jr  
    在FRED中使用0屈光度来创建的,光瞳加在了透镜的前面。材料是创建一个新的材料并选择类型“Model Material”,输入的参数是nd和vd. D6dliU?k  
    M }! qH.W  
    光源 zv7)JH7EV&  
    BTzBT%mP  
    多个光源定义来分析该模型的不同特性。图1显示了所以的光源和提示信息告诉您他们可以用来做什么。 ~.tl7wKkR/  
    x?UAj8z6  
    /1v:eoF;  
    图1. 光源和提示信息使用
    x8xz33  
    除了“Letter F”之外的所有光源的光线位置设定在了孔径光阑位置处,并增加了pre-propagation distance= -8。尽管光线在光瞳处创建,规定的传输方向相对于光线位置在pre-propagation distance之后。这意味着光束沿着Z轴在眼睛的前面以平行光入射,而不是在光瞳处入射。 +7Uv|LZ~@  
    fN1b+ d~*6  
    在往下看是内置的脚本用来修改屈光度,使其为4(250mm),光源“Letter F”在视网膜处生成一个字母为F的图像。绿色的光线聚焦的非常好而红色和蓝色光线有一点的模糊。使用Positions Spot Diagram分析工具来观察最为合适。 !kG|BJ$j  
    k|czQ"vaI  
    图2. 字母F光源的设定方法光 v.- r %j{I  
     _!_^B  
    图3. 字母F在视网膜上位置点列图
    qSDn0^y  
    视网膜的散射 S"VO@)d  
    **\?-*c=U  
    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。 !F:mD ZeY  
    C B`7KK  
    ,(RpBTV  
    图4. 视网膜朗伯散射设定
    (q0vql  
    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。 pw&k0?K#  
    VJ8'T"^Hf  
    (j~T7og  
    图5. 视网膜重点采样规格设定
    0x,**6  
    脚本 I94-#*~I  
    UlWm). b;v  
    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: HOx+umjxW  
    Qqi?DW1)-  
    图6. 用户对话框的创建与编辑
    }$'XV.  
    图7. 用户对话框编辑器
    P:_bF>r ?  
    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。 M}j[{wW3  
    余下的脚本计算与屈光度有关的所有参数。 Yi]`"\  
    =k*XGbU  
    分析 =W;e9 6#  
    H|0-Al.{  
    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^O&A\+;  
    J0 dY%pH#  
    图7. 字母F在视网膜上颜色分析
    x#5vdBf  
    脚本代码 fJP *RVz  
    HYmUD74FR  
    Option Explicit     'Remove this to enable non-dimensioned variables to be used. [!>9K}z,=  
    5*f54g"'  
    Dim entity As T_ENTITY {n&n^`Em  
    Dim op As T_OPERATION A|,qjiEJCc  
    Dim mat As T_MODELMATERIAL W"*2,R[}%  
    Dim A As Double $hHV Ie]+  
    Dim pupilDiam As Double CPL,QVO9  
    Dim eID As Long aNs8T`  
    Dim parID As Long MD*dq  
    Dim count As Integer ZPY&q&R  
    Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double ]kXW eY<  
    Dim tlens As Double, nlens As Double 1hlU 6 =Y  
    Dim curv As Double, conic As Double k$ T  
    Dim ok As Long _Rb2jq(&0  
    w[D]\>QHa  
    Sub Main *7-rm  
    REgM  
        '用户输入对话框 vBJxhK-  
        Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 0{uaSR  
            TextBox 220,21,40,21,.TextBox1 'default: 0 o<iU;15  
            Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 !yVY[  
            OKButton 40,91,90,21 5~/EAK`  
            CancelButton 190,91,90,21 )[cuYH>  
            Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 a??8)=0|}  
            TextBox 220,49,40,21,.TextBox2 'default: 4 P[-do  
        End Dialog _~MX~M3MB  
        Dim dlg As UserDialog v-SX PL]_^  
    n-xdyJD  
        ok = Dialog (dlg) y3o3G  
    ^[r1Dk  
        If ok=0 Then    'cancel button was pressed ?]D))_|G  
            Print "Execution cancelled." +}M3O]?4  
            End 9P ACXW0  
        End If a;^lOU|L{  
    |0oaEd^*}  
        'Assign accommodation and pupil diameter & use defaults if field left empty W7b m}JHn  
        If dlg.TextBox1 = "" Then :fwtPvLo  
            A = 0           'Default accommodation |dbKK\ X9  
        Else \o/eF&  
            A = CDbl(dlg.TextBox1) ;Vc|3  
        End If uDXV@;6<  
    4bp})>}jB  
        If dlg.TextBox2 = "" Then oQ,<Yx%E3  
            pupilDiam = 4   'Default pupil diameter H8[A*uYL  
        Else 4oH ,_sr  
            pupilDiam = CDbl(dlg.TextBox2) })P!7t  
        End If F[$cE  
    X[r0$yuE  
        Print " " c ?EvrtND  
        Print "Accommodation = " & A & " Diopters" 9]w?mHslE  
        Print "Pupil Diameter = " & pupilDiam & " mm" #=S^i[K/  
    Hnk&2bY  
        ' Calculate new parameters with accommodation hm d3W`8D  
        taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness |idw?qCn  
    ~CkOiWC0  
        Rant = 12.0 - 0.4*A                     'Radius of anterior lens |%F,n2  
        CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens A]5];c  
    R'zi#FeP  
        Rpost = -5.224557 + 0.2*A               'Radius of posterior lens HnKgD:  
        CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens Wh| T3&  
    j}",+H v  
        tlens = 3.767 + 0.04*A                  'Lens thickness ;m#4Q6k)V?  
    ~gff{Nzk  
        nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction @`C'tfG/4  
    % g  
        'Adjust parameters to account for accommodation bTrusSAl  
    z8awND  
        '************************************************************************* j|wN7@Zc  
        'Aqueous thickness (Position of Lens) $.,B2}'  
        '************************************************************************* @-Q l6k  
        eID = FindFullName( "Geometry.Arizona Eye.Lens" ) (@5`beEd  
        GetCustomElement eID, entity SU4i'o  
    T9w=k)  
        parID = FindFullName( "Geometry.Arizona Eye" ) S<Gm*$[7  
    9l &q}  
        ' Delete any shift(s) in z  [. 9[?8  
        count = 0 ERIMz ,  
        While GetOperationCount(eID)>count !|xB>d q?  
            GetOperation eID, count, op [UZ r|F  
            If op.Type="ShiftZ" Then 0jlM~H  
                DeleteOperation eID,count X1`3KqK<9  
                count=count-1 o>,r<  
            End If qc @cd i  
            count=count+1 ?@$xLUHR4  
        Wend =X7kADRq  
    r5S/lp+Y+N  
        'Set new shift in <n]PD;.4  
        op.Type = "ShiftZ" b;UDgq8v  
        op.val1 = taq zU ~ Ff"<  
        op.parent = parID 7GsKD=bl]  
        AddOperation eID, op } #H,oy;Dz  
        Print "Set aqueous humor thickness = " & taq-0.55 px K&aY8  
    "d$~}=a[  
        '************************************************************************* zT78FliY6  
        'Radius and conic constant of anterior lens 77O$^fG2  
        '************************************************************************* =b:XL#VA  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) )8W! |  
        GetConic eID, entity, curv, conic 8(\}\4G_  
    196a~xNV  
        SetConic eID, entity, 1/Rant, CCant 1l#46?]~  
        Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant bp:`m>4<  
    ^%9oeT{  
        '************************************************************************* ylZQwICk  
        'Radius and conic constant of posterior lens %T]^,y$n  
        '************************************************************************* N:| :L:<1  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) ]5f;Kz)  
        GetConic eID, entity, curv, conic 37zB X~  
    Z5 IWoY  
        SetConic eID, entity, 1/Rpost, CCpost r9_ ON|  
        Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost ]E<Z5G1HD  
    YJ6~P   
        '************************************************************************* W"vLCHTh  
        'Lens thickness (Position of posterior lens surface) G9Uc }z  
        '************************************************************************* *{w0=J[15  
    -|m3=#  
        parID = FindFullName( "Geometry.Arizona Eye.Lens" ) +112{v=!i  
    '37 {$VHw  
        ' Delete any z-shift(s) Mc@9ivwL#  
        count = 0 ZDFq=)0C  
        While GetOperationCount(eID)>count |?^<=%  
            GetOperation eID, count, op JKM(fX+  
            If op.Type="ShiftZ" Then gA(npsUHI  
                DeleteOperation eID,count R|\eBnfI  
                count=count-1 "i;.>  
            End If bN. G%1  
            count=count+1 ^~[7])}g6  
        Wend 5Z!$?J4Rl  
    ~rBFP)  
        'Set new z-shift Qt+D ,X  
        op.Type = "ShiftZ" )sm9%|.&  
        op.val1 = tlens _R ii19k  
        op.parent = parID LBy`N_@  
        AddOperation eID, op Zt3sU_  
        Print "Set lens thickness = " & tlens M#'7hm6  
     _'!?fA  
        '************************************************************************* ['}|#3*w  
        'Lens index of refraction  <J;O$S  
        '************************************************************************* |:R\j0t  
        eID = FindMaterial( "Lens" ) :.+w'SEn4M  
        GetModelMaterial eID, mat TRi#  
     ydzsJ+dx  
        mat.Nd = nlens tw$EwNI[  
        SetModelMaterial eID, mat 9xK>fM&u  
        Print "Set lens index of refraction = " & nlens 5?>4I"ne  
    71nZi`AR  
        '************************************************************************* 0(y*EJA$  
        'Pupil diameter r*`e%`HU  
        '************************************************************************* qIZ+%ZOu  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) ,zoHmV1Wd+  
    .z,-ThTH@\  
        'Adjust pupil diameter (trimming volume inner hole) $vXY"-k  
    < c^'$  
        SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder"  ImhkU%  
    ?C2(q6X+s  
        ' Adjust pupil location to just in front of the lens }h;Z_XF&  
        parID = FindFullName( "Geometry.Arizona Eye" ) s=jmvvs_V}  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) W]D YfR,  
        count = 0 :g|.x  
        While GetOperationCount(eID)>count 6-wpR  
            GetOperation eID, count, op 8`*5[ L~~/  
            If op.Type="ShiftZ" Then 1-p#}VX  
                DeleteOperation eID,count #a}w&O";  
                count=count-1 -KGJr  
            End If $=plAi  
            count=count+1 *,X)tZ6VX  
        Wend E^rBs2;9  
        op.Type = "ShiftZ" _E?tVx.6  
        op.val1 = taq-0.01 R9A:"sJ  
        op.parent = parID @JlT*:Dz  
        AddOperation eID, op ELwXp|L  
    \2/X$x<?X  
        Print "Set pupil diameter = " & pupilDiam Vl1.]'p_  
    ]  & ]G  
        'Update AZ Eye subassembly Description Zl3l=x h  
        eID = FindFullName( "Geometry.Arizona Eye" ) L8D=F7  
        GetEntity eID, entity V Dnrm*  
        entity.Description = "Accommodation = " & A & "D" J0IKI,X.  
        SetEntity eID, entity DL,R~  
    *I?-A(e  
        Update N#M>2b<A/T  
        Print "DONE!" : _Y^o  
         -`q!mdA2  
    End Sub qY-aR;  
    "T5jz#H#/  
    如果屈光度是4,光瞳直径是4,则会输出如下数据: zKP[]S-  
    TE&E f$h  
    Accommodation = 4 Diopters 9mvy+XD  
    Pupil Diameter = 4 mm s>G6/TTH6  
    Set aqueous humor thickness = 2.81 ;0WAfu}#H  
    Set anterior lens radius = 10.4 and conic constant = -2.375869 "-S!^h/v  
    Set posterior lens radius = -4.424557 and conic constant = -3.081019 "#wAGlH6>  
    Set lens thickness = 3.927 Ut~YvWc9  
    Set lens index of refraction = 1.42672 GThGV"  
    Set pupil diameter = 4 Q3ZGN1aX<  
    DONE! `P\H{  
     
    分享到