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 wC{ =o`v  
s$C;31k  
人眼光学模型可用来设计眼科用设备,光学系统注定了要与人眼一起使用。本文演示了这样一个模型:Arizona眼睛模型,在Jim Schwiegerling教授的书中有详细描述:《Field Guide to Visual and Ophthalmic Optics》。AZ眼睛模型达到了基于平均临床数据所决定的轴上和轴外像差等级。FRED文件包含了此眼睛模型及几个用来分析它的光源,并包括一个基于想要的屈光度来调整模型的内嵌脚本。 yZb@  
1;fs`k0p  
模型 8!3+Obj  
PP.k>zsx  
模型的定义如表1种所示,由半径、圆锥常数、折射率、阿贝数、到下一面的距离等一系列表面组成。一些参数由屈光度(A)来决定。 [_|i W%<`  
Table 1. AZ眼睛模型的定义
[attachment=111140]
%saTyF,  
'&?47+W  
在FRED中使用0屈光度来创建的,光瞳加在了透镜的前面。材料是创建一个新的材料并选择类型“Model Material”,输入的参数是nd和vd. >%qGK-_  
3Nr8H.u&q  
光源 Kw(/#C:$  
U> e@m?  
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。 GE Xz)4[  
L^RyJ;^c  
[attachment=111141]
图1. 光源和提示信息使用
csRba;Z[  
7vNS@[8  
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。 6:v8J1G(<  
qI<*Cze  
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。 ?TMo6SU  
[attachment=111142]
图2. 字母F光源的设定方法光 PgB=<#9  
a+A/l  
[attachment=111143]
图3. 字母F在视网膜上位置点列图
S&_ZQLiQ$  
6du"^g  
视网膜的散射 Oq*a4_R'YV  
Vn];vN  
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。 j[iJo 5  
7; T S  
[attachment=111144]
图4. 视网膜朗伯散射设定
@F=ZGmq  
0 v/+%%4}  
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。 Jfo|/JQ  
V *S|Qy!p  
[attachment=111145]
图5. 视网膜重点采样规格设定
QdO$,i'  
PA`b~Ct  
脚本 - CM;sXq  
tDy1Gh/c  
内置脚本使用对话框显示屈光度和光瞳直径的数值设置。使用FRED Basic脚本创建和使用对话框非常容易。图6显示了如何获取用户自定义对话框,如下图所示: m$QFtrvy  
[attachment=111146]
图6. 用户对话框的创建与编辑
- /#3U{O  
[attachment=111147]
图7. 用户对话框编辑器
+(PtOo.  
js;IUSj.  
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。 0<nKB}9  
余下的脚本计算与屈光度有关的所有参数。 d`({z]W;  
_[0Ugfz (  
分析 wKk  
h=`rZC  
屈光度为4,光瞳直径为4mm,字母F点在视网膜上所成的像。 [0/?(i|  
[attachment=111148]
图7. 字母F在视网膜上颜色分析
)I1LBvfQ  
<Y~V!9(~{Q  
脚本代码 Qksw+ZjY#{  
<@F4{*  
  1. Option Explicit     'Remove this to enable non-dimensioned variables to be used. xs.[]>nQN  
    d[TcA2nF  
    Dim entity As T_ENTITY KC}B\~ +  
    Dim op As T_OPERATION r)+dK }xl  
    Dim mat As T_MODELMATERIAL V X211U.Q  
    Dim A As Double 5wGyM10  
    Dim pupilDiam As Double Plm3vk=  
    Dim eID As Long -BEPpwb<g  
    Dim parID As Long "_?^uymw  
    Dim count As Integer $PrzJc  
    Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double tG%R_$*  
    Dim tlens As Double, nlens As Double  ~ikTo -  
    Dim curv As Double, conic As Double Hsp|<;Yg  
    Dim ok As Long .~b6wi&n  
    C$,S#n@  
    Sub Main 2GZUMXK  
    Aqp3amW!  
        '用户输入对话框 u6(7#n02  
        Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 Bm~>w`1wK  
            TextBox 220,21,40,21,.TextBox1 'default: 0 ?KS9Dh  
            Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 &<tji8Dj  
            OKButton 40,91,90,21 /Zm@.%.  
            CancelButton 190,91,90,21 ~x4Y57  
            Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 *qz]vUb/0  
            TextBox 220,49,40,21,.TextBox2 'default: 4 ry7(V:ic  
        End Dialog <<UlFE9"  
        Dim dlg As UserDialog ?I7H ):  
    v'_tna6`O  
        ok = Dialog (dlg) i"_f46r P  
    q!O~*   
        If ok=0 Then    'cancel button was pressed K32eZv`T7  
            Print "Execution cancelled." oiFtPki  
            End (TnYUyFP`  
        End If \u)s Zh  
    f5sk,Z  
        'Assign accommodation and pupil diameter & use defaults if field left empty  t%FS 5  
        If dlg.TextBox1 = "" Then 8nZPY)o  
            A = 0           'Default accommodation Crww\#E;  
        Else }bB_[+YV`{  
            A = CDbl(dlg.TextBox1) 4Pz9&^K  
        End If { ET+V  
    ZnmBb_eX  
        If dlg.TextBox2 = "" Then 08.dV<P  
            pupilDiam = 4   'Default pupil diameter B<0lif|  
        Else D ORFK  
            pupilDiam = CDbl(dlg.TextBox2) Z ,T TI>P  
        End If %/sf#8^m  
    nY~CAo/:  
        Print " " cFH,fj  
        Print "Accommodation = " & A & " Diopters" M4DRG%21  
        Print "Pupil Diameter = " & pupilDiam & " mm" W6\s@)b;  
    B*?v`6  
        ' Calculate new parameters with accommodation K-#Rm%J+Wy  
        taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness fx_7B (  
    {8JJ$_  
        Rant = 12.0 - 0.4*A                     'Radius of anterior lens }O!LTD  
        CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens zL7+HY* 3o  
    */Y@:Sjf  
        Rpost = -5.224557 + 0.2*A               'Radius of posterior lens V qYe0-^=P  
        CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens nE/T)[1|  
    g(<@r2p  
        tlens = 3.767 + 0.04*A                  'Lens thickness Xw![}L >  
    *_^AK=i  
        nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction 0}w>8L7i{  
    .|o7YTcR:  
        'Adjust parameters to account for accommodation 'zpj_QM  
    ggbew6L$Z  
        '************************************************************************* T4Zp5m")  
        'Aqueous thickness (Position of Lens) Bj\0RmVa1  
        '************************************************************************* Va !HcG1^:  
        eID = FindFullName( "Geometry.Arizona Eye.Lens" ) vU~#6sl  
        GetCustomElement eID, entity .}z&$:U9[  
    ZA:YoiaC#  
        parID = FindFullName( "Geometry.Arizona Eye" ) G>H&M#7K  
     /@%  
        ' Delete any shift(s) in z &z,w0FOre  
        count = 0 y]@_DL#J=  
        While GetOperationCount(eID)>count GJH6b7I  
            GetOperation eID, count, op r,0> 40^  
            If op.Type="ShiftZ" Then *t*yozN  
                DeleteOperation eID,count  |\,e9U>  
                count=count-1 \:O5,wf2  
            End If U?@UIhtM|  
            count=count+1 sLB{R#Pt  
        Wend Q=>@:1=  
    O5e9vQH  
        'Set new shift in JLs7[W)O  
        op.Type = "ShiftZ" Bz ]64/  
        op.val1 = taq O </<  
        op.parent = parID scrNnO[3j  
        AddOperation eID, op cMtkdIO  
        Print "Set aqueous humor thickness = " & taq-0.55 6rPe\'n=B  
    c\-I+lMBi  
        '************************************************************************* ))Aj X  
        'Radius and conic constant of anterior lens whRc YnJ  
        '************************************************************************* ("IRv>} 0  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) L5PN]<~T  
        GetConic eID, entity, curv, conic DJ=miJI'  
    +EkZyM~z2  
        SetConic eID, entity, 1/Rant, CCant q/&Z6LJ)  
        Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant \Mt(9jNK  
    |J~;yO SD  
        '************************************************************************* szWh#O5=  
        'Radius and conic constant of posterior lens 4qiG>^h9  
        '************************************************************************* GHH1jJ_[7  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) J6&;pCAi  
        GetConic eID, entity, curv, conic 1C'lT,twl  
    2<|+h= &  
        SetConic eID, entity, 1/Rpost, CCpost 1Te: &d  
        Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost {TlS)i`  
    $yhQ)@#1  
        '************************************************************************* a i}8+L8-  
        'Lens thickness (Position of posterior lens surface) \e( h6,@  
        '************************************************************************* |W{z,e01x  
    J/ <[irC  
        parID = FindFullName( "Geometry.Arizona Eye.Lens" ) .4.zy]I  
    idGM%Faur  
        ' Delete any z-shift(s) pSc<3OI  
        count = 0 &!m;s_gi  
        While GetOperationCount(eID)>count ^!N_Nx/M  
            GetOperation eID, count, op 9C3q4.$D  
            If op.Type="ShiftZ" Then >8oRO  
                DeleteOperation eID,count u;;]S!:M  
                count=count-1 7S1 Y)  
            End If VO[s:e9L  
            count=count+1 M}3>5*!=  
        Wend MQw{^6Z>1  
    _T8#36iR  
        'Set new z-shift ;lnh;0B  
        op.Type = "ShiftZ" kcM9 ,bG  
        op.val1 = tlens V5%B ,.d:  
        op.parent = parID om9fg66  
        AddOperation eID, op v-_K'm  
        Print "Set lens thickness = " & tlens D_(xhM  
    fMI4'.Od  
        '*************************************************************************  :v8j3=  
        'Lens index of refraction 4LJUO5(y@  
        '************************************************************************* q-X)tH_+w@  
        eID = FindMaterial( "Lens" ) #Ubzh`v  
        GetModelMaterial eID, mat * t{A=Wk  
    mEr* n  
        mat.Nd = nlens $kvF]|<bu  
        SetModelMaterial eID, mat ko $bCG%  
        Print "Set lens index of refraction = " & nlens Quc9lL  
    cAV9.VS<L  
        '************************************************************************* a[[u>oHyd  
        'Pupil diameter srO {Ci0  
        '************************************************************************* F+v?2|03  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) 2< w/GX.  
    !7P 1%/  
        'Adjust pupil diameter (trimming volume inner hole) 03iO4yOu  
    Z"] ben  
        SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" Iy6 "2$%a  
    #rF|X6P  
        ' Adjust pupil location to just in front of the lens _<=U.T`  
        parID = FindFullName( "Geometry.Arizona Eye" ) a UAPh  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) #4Xe zj,g*  
        count = 0 K q: +{'  
        While GetOperationCount(eID)>count 0^?(;AK  
            GetOperation eID, count, op Z,! w.TYo  
            If op.Type="ShiftZ" Then 4\Mh2z5  
                DeleteOperation eID,count &d[&8V5S  
                count=count-1 J`Q#p%W  
            End If 1 nIb/nY  
            count=count+1 ,A h QA  
        Wend #]q<fhJhr$  
        op.Type = "ShiftZ" 7-nwfp&|$  
        op.val1 = taq-0.01 `LEk/b1(P  
        op.parent = parID .3Jggp  
        AddOperation eID, op Z; r}G m  
    ?tQUZO  
        Print "Set pupil diameter = " & pupilDiam 66,?f<b  
    9@nX 6\ ,  
        'Update AZ Eye subassembly Description ahU\(=  
        eID = FindFullName( "Geometry.Arizona Eye" ) K!lGo3n]  
        GetEntity eID, entity /NNe/7'l  
        entity.Description = "Accommodation = " & A & "D" 9\0  
        SetEntity eID, entity @D[jUC$E  
    q UY;CEf  
        Update V)^nVD)e  
        Print "DONE!" 24}r;=U  
    wwF]+w%lOw  
    End Sub .\7R/cP}{A  
    _1VtVfiZ{  
    如果屈光度是4,光瞳直径是4,则会输出如下数据: vClD)Ar  
    J0~Ha u  
    Accommodation = 4 Diopters 6! \a8q'z  
    Pupil Diameter = 4 mm L0/0<d(K  
    Set aqueous humor thickness = 2.81 qh Rs5QXL  
    Set anterior lens radius = 10.4 and conic constant = -2.375869 <VS\z(K  
    Set posterior lens radius = -4.424557 and conic constant = -3.081019 MW=2GhD=  
    Set lens thickness = 3.927 S^]i  
    Set lens index of refraction = 1.42672 EGf9pcUEO&  
    Set pupil diameter = 4 N J9H=  
    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