首页 -> 登录 -> 注册 -> 回复主题 -> 发表主题
光行天下 -> 讯技光电&黉论教育 -> Arizona眼睛模型 [点此返回论坛查看本帖完整版本] [打印本页]

infotek 2022-02-25 09:52

Arizona眼睛模型

简介 s S5fd)x  
rS )b1nPA  
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。 pp]_/46nN  
b"M`@';+  
模型 7grt4k  
r1oku0o  
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。 b"nG-0JR  
Table 1. AZ眼睛模型的定义
[attachment=111140]
.S!>9X,  
Pc)VK>.fc  
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. $iqi:vY  
BKQIo)g.G  
光源 *SkiFEoD  
ZSPgci  
多个光源定义来分析该模型的不同特性。图1显示了所以的光源和提示信息告诉您他们可以用来做什么。 (+UmUx=  
oY%"2PW1B  
[attachment=111141]
图1. 光源和提示信息使用
n<?SZ^X{,/  
}B"|z'u  
除了“Letter F”之外的所有光源的光线位置设定在了孔径光阑位置处,并增加了pre-propagation distance= -8。尽管光线在光瞳处创建,规定的传输方向相对于光线位置在pre-propagation distance之后。这意味着光束沿着Z轴在眼睛的前面以平行光入射,而不是在光瞳处入射。 tyuk{* Me:  
3X$Q,  
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。 N(:nF5>_  
[attachment=111142]
图2. 字母F光源的设定方法光 H 5U x.]y  
wI! +L&Q  
[attachment=111143]
图3. 字母F在视网膜上位置点列图
HX3D*2v":  
6KEykw j  
视网膜的散射 ^p 2.UW  
dXiE.Si  
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。 EK?@Z.q+  
N )zPxQ  
[attachment=111144]
图4. 视网膜朗伯散射设定
v._Egk0  
K[uY+!'1  
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。 4YDT%_h0  
- J"qrpZ^  
[attachment=111145]
图5. 视网膜重点采样规格设定
w dGpt_  
E+}GxFG-:  
脚本 VyecTU"W  
q]"2hLq  
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: s>jr1~~3O_  
[attachment=111146]
图6. 用户对话框的创建与编辑
E3S%s  
[attachment=111147]
图7. 用户对话框编辑器
-(\1r2 Y  
By?nd)  
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。 J}Qs"+x  
余下的脚本计算与屈光度有关的所有参数。 =Kc|C~g  
,< @,gZru  
分析 L#`2.nU  
}_{y|NW  
屈光度为4,光瞳直径为4mm,字母F点在视网膜上所成的像。 E?Zb~xk  
[attachment=111148]
图7. 字母F在视网膜上颜色分析
{ExII<=6  
t_jyyHxoZ:  
脚本代码 +"cRhVR  
O87"[c`>  
  1. Option Explicit     'Remove this to enable non-dimensioned variables to be used. @B,j;2eb  
    oL<BLr9>  
    Dim entity As T_ENTITY YBX)eWslK  
    Dim op As T_OPERATION {TyCj?3B  
    Dim mat As T_MODELMATERIAL U^%9 )4bj  
    Dim A As Double z,pNb%*O  
    Dim pupilDiam As Double R'6@n#:  
    Dim eID As Long -xJX_6}A  
    Dim parID As Long wgY6D!Y   
    Dim count As Integer _*s~`jn{H  
    Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double tg~A}1o`0  
    Dim tlens As Double, nlens As Double Wrmgu}q  
    Dim curv As Double, conic As Double UTZ776`S&X  
    Dim ok As Long Q  |  
    a9[mZVMgUK  
    Sub Main Y!SE;N&  
    m_a^RB(  
        '用户输入对话框 XZ.7c{B<  
        Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 C<_ Urnmn  
            TextBox 220,21,40,21,.TextBox1 'default: 0 JXH",""bq  
            Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 @-0Fe9 n=  
            OKButton 40,91,90,21 k+FMZ, D|  
            CancelButton 190,91,90,21 wGg0 hL  
            Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 = 0 ,|/1~  
            TextBox 220,49,40,21,.TextBox2 'default: 4 }N?g|  
        End Dialog qQ^d9EK'?~  
        Dim dlg As UserDialog yahAD.Xuo@  
    6`acg'sk>  
        ok = Dialog (dlg) jDR')ascn  
    _B)s=Snx  
        If ok=0 Then    'cancel button was pressed G'u|Q mb1  
            Print "Execution cancelled." k@S)j<  
            End 8qn 9|  
        End If Ua %UbAt  
    %NNj9Bl<VV  
        'Assign accommodation and pupil diameter & use defaults if field left empty jh[ #p?:  
        If dlg.TextBox1 = "" Then KYp[Gs  
            A = 0           'Default accommodation nE_Cuc>K\  
        Else z<!O!wX_aI  
            A = CDbl(dlg.TextBox1) le.anJAr  
        End If rWA6X DM7  
    C,fY.CeI  
        If dlg.TextBox2 = "" Then 0Z"s_r}h  
            pupilDiam = 4   'Default pupil diameter bl=ku<}@  
        Else vv+km+  
            pupilDiam = CDbl(dlg.TextBox2) 2`EVdl7B]  
        End If i0>]CJG  
    Nb0Ik/:<  
        Print " " '3^Q14`R  
        Print "Accommodation = " & A & " Diopters" <:">mV+/  
        Print "Pupil Diameter = " & pupilDiam & " mm" uQnT[\k?  
    C0QM#"[  
        ' Calculate new parameters with accommodation U9 #w  
        taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness V@[rf<,  
    [ 7g><  
        Rant = 12.0 - 0.4*A                     'Radius of anterior lens RND9D\7  
        CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens pr_>b`p6  
    X3<K 1/<  
        Rpost = -5.224557 + 0.2*A               'Radius of posterior lens w9MoT.kI}  
        CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens /2xSNalC  
    Nar>FR7ut  
        tlens = 3.767 + 0.04*A                  'Lens thickness (-,>qMQs  
    b?8)7.{F{  
        nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction +y/55VLq  
    U6<M/>RG$  
        'Adjust parameters to account for accommodation Xd3}Vn=  
    49AW6H.JT  
        '************************************************************************* rh66_eV  
        'Aqueous thickness (Position of Lens) +>SRrIi  
        '************************************************************************* H]&gW/=  
        eID = FindFullName( "Geometry.Arizona Eye.Lens" ) zyFUl%  
        GetCustomElement eID, entity d1c0l{JV3  
    /`3 #4=5-  
        parID = FindFullName( "Geometry.Arizona Eye" ) xR?V,uV'$&  
    [*Uu#9  
        ' Delete any shift(s) in z BJk Z2=  
        count = 0 I-kWS 4  
        While GetOperationCount(eID)>count 19W:-Om  
            GetOperation eID, count, op rQb7?O@-  
            If op.Type="ShiftZ" Then U<^F4*G  
                DeleteOperation eID,count "j^MB)YD  
                count=count-1 WF[bO7:  
            End If j/KO|iNL2  
            count=count+1 jo9gCP.  
        Wend 1& ^?U{  
    wMWW=$h#\  
        'Set new shift in P6\6?am  
        op.Type = "ShiftZ" Yf}xwpuLk  
        op.val1 = taq A%X X5*  
        op.parent = parID <CZgQ\Mt  
        AddOperation eID, op sILSey5`  
        Print "Set aqueous humor thickness = " & taq-0.55 __Nv0Ru  
    w!&~??&=}  
        '************************************************************************* Z6Fp\aI8@  
        'Radius and conic constant of anterior lens A&"%os  
        '************************************************************************* BUsV|e\  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) fQdK]rLj  
        GetConic eID, entity, curv, conic tU :EN;H  
    k XrlSaIc  
        SetConic eID, entity, 1/Rant, CCant +?dl`!rE  
        Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant [0y$! f4  
    !)pdamdA  
        '************************************************************************* Ef)yQ  
        'Radius and conic constant of posterior lens =Vw 5q},3  
        '************************************************************************* t9cl"F=  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) 'xE _Cj  
        GetConic eID, entity, curv, conic T.m mmT  
    >V$ Gx>I  
        SetConic eID, entity, 1/Rpost, CCpost S/tIwG ~e3  
        Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost [p;E~-S  
    X3%Ic`Lq#  
        '************************************************************************* y3G `>  
        'Lens thickness (Position of posterior lens surface) T'H::^9:E  
        '************************************************************************* SUM4Di7  
    t2BL( yB  
        parID = FindFullName( "Geometry.Arizona Eye.Lens" ) >e,mg8u6$  
    Wwujh2g"0|  
        ' Delete any z-shift(s) cC'x6\a  
        count = 0 bm% $86  
        While GetOperationCount(eID)>count / JkC+7H4  
            GetOperation eID, count, op U#&7p)4(  
            If op.Type="ShiftZ" Then tmUFT  
                DeleteOperation eID,count !\Xm!I8  
                count=count-1 L+}n@B  
            End If Qnd5X`jF#  
            count=count+1 -E"GX  
        Wend H1n1-!%d  
    VVP:w%yW  
        'Set new z-shift ^ BQrbY  
        op.Type = "ShiftZ" 26vp1  
        op.val1 = tlens @&|l^ 1  
        op.parent = parID }a AH  
        AddOperation eID, op L|@y&di  
        Print "Set lens thickness = " & tlens *3/T;x.  
    a ^d8I  
        '************************************************************************* Y5ZZ3Ati  
        'Lens index of refraction rgmF:C  
        '************************************************************************* 4k-+?L!/G  
        eID = FindMaterial( "Lens" ) qt%D'  
        GetModelMaterial eID, mat >9e(.6&2XZ  
    !`41q=r  
        mat.Nd = nlens V-'K6mn;  
        SetModelMaterial eID, mat %wcSM~w  
        Print "Set lens index of refraction = " & nlens VA *y|Q6  
    +5VLw  
        '************************************************************************* &`0/CV  
        'Pupil diameter |waIpB(  
        '************************************************************************* ,to+oSZE  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) Urr#N  
    GaX[C<Wt  
        'Adjust pupil diameter (trimming volume inner hole) s*U1  
    <S?ddp2  
        SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" ] e. JNo  
    AL#4_]m'  
        ' Adjust pupil location to just in front of the lens tyaA\F57  
        parID = FindFullName( "Geometry.Arizona Eye" ) >SPh2[f  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) Z87_#5  
        count = 0 M9zfT !-  
        While GetOperationCount(eID)>count sVG(N.y  
            GetOperation eID, count, op [kE."#  
            If op.Type="ShiftZ" Then fd-q3 _f  
                DeleteOperation eID,count J{^RkGF  
                count=count-1 Xp0F [>h  
            End If M%jPH  
            count=count+1 V3 ~~  
        Wend a5a($D  
        op.Type = "ShiftZ" 3U_2!zF3_  
        op.val1 = taq-0.01 Jgnhn>dHe  
        op.parent = parID ?QE,;QtpK  
        AddOperation eID, op lz1 wO5%h  
    t%F0:SH  
        Print "Set pupil diameter = " & pupilDiam \=_{na_  
    AU2i%Q!  
        'Update AZ Eye subassembly Description J9~ g|5  
        eID = FindFullName( "Geometry.Arizona Eye" ) c("_bOAT  
        GetEntity eID, entity pb~pN  
        entity.Description = "Accommodation = " & A & "D" 7jdb)l\p=  
        SetEntity eID, entity M)SEn/T-  
    b0oMs=uBn  
        Update zc[Si bT  
        Print "DONE!" Ja9e^`i;  
    \L"kV!>  
    End Sub +SwR+H)?  
    "I(xgx*  
    如果屈光度是4,光瞳直径是4,则会输出如下数据: I_RsYw  
    ,c NLkoN  
    Accommodation = 4 Diopters h<$MyN4]g  
    Pupil Diameter = 4 mm t.;LnrY  
    Set aqueous humor thickness = 2.81 H)n9O/u  
    Set anterior lens radius = 10.4 and conic constant = -2.375869 8YbE`32  
    Set posterior lens radius = -4.424557 and conic constant = -3.081019 jYKor7KTqT  
    Set lens thickness = 3.927 E~6c-Lw  
    Set lens index of refraction = 1.42672 t<#h$}=:Vt  
    Set pupil diameter = 4 SJHr_bawd  
    DONE!
silence唯爱 2022-02-25 13:53
太赞了,终于看到完整的文档
查看本帖完整版本: [-- Arizona眼睛模型 --] [-- top --]

Copyright © 2005-2025 光行天下 蜀ICP备06003254号-1 网站统计