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 2023-04-27 08:29

Arizona眼睛模型

q/d5P  
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。 wB1-|= K1  
Mc#O+'](f  
模型 = C$ @DNEc  
110>p  
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。 Pp JE|[]  
Table 1. AZ眼睛模型的定义
s= GOB"G  
M&}oat*  
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. 7YQK@lS  
\gJapx(  
光源 O3<Y_I^  
@ ^XkU(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。  }]n>A  
V{AH\IV-  
图1. 光源和提示信息使用
@gu77^='  
XEgx#F ;F  
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。 dc\u$'F@S  
2EqsfU* I  
在往下看是内置的脚本用来修改屈光度,使其为4(250mm),光源“Letter F”在视网膜处生成一个字母为F的图像。绿色的光线聚焦的非常好而红色和蓝色光线有一点的模糊。使用Positions Spot Diagram分析工具来观察最为合适。 ga 2Q3mV  
图2. 字母F光源的设定方法光 U4^p({\|-  
vxzf[  
图3. 字母F在视网膜上位置点列图
%Zv(gI`A  
 n_xa)  
视网膜的散射 Jegx[*O>b  
K,L>  
在散射文件中,有一个名为“Retina surface”的72%的反射型朗伯散射,它为视网膜的散射提供了一个粗略的近似。为了模拟来自视网膜的散射,改变自定义元件“Eye ball” 下的视网膜的表面从“halt all” 到”Allow All”。并使几何中“plane”可追迹。 5.C[)`_  
Ck/_UY|  
图4. 视网膜朗伯散射设定
LBbo.KxAe3  
?V\9,BTb)  
注意在视网膜的表面有散射重点采样规格定义,在“Scatter”标签的底部可获取该信息。“toward pupil”指定散射光朝向光瞳,半角度10度。 bH WvKv+  
;+TF3av0zq  
图5. 视网膜重点采样规格设定
@6i8RmOu}  
tmY-m,U  
脚本 )kY _"= d  
Fl'xmz^  
内置脚本使用对话框显示屈光度和光瞳直径的数值设置。使用FRED Basic脚本创建和使用对话框非常容易。图6显示了如何获取用户自定义对话框,如下图所示: dx?njR  
图6. 用户对话框的创建与编辑
D?*sdm9r`  
图7. 用户对话框编辑器
~d#;r5>  
VATXsD  
如果“OK”按钮按下,将会核对对话框下面的代码行,如果点击取消则脚本终止。然后输入的参数赋予变量,如果此处是保留为空白,则使用默认值。因此,如果没有值输入并点击“OK”按钮,则脚本是以屈光度为0,光瞳直径为4mm来运行的。 tE9_dR^K  
余下的脚本计算与屈光度有关的所有参数。 4-}A'fTU8  
ad3z]dUZ9  
分析 .' N O~  
C$..w80/1  
屈光度为4,光瞳直径为4mm,字母F点在视网膜上所成的像。 bh;b` 5  
图7. 字母F在视网膜上颜色分析
thm3JfQt  
qY~$wVY(  
脚本代码 )zL"r8si  
(zTI)EV  
Option Explicit     'Remove this to enable non-dimensioned variables to be used. /Y\E68_Fh  
!>kv.`|7~  
Dim entity As T_ENTITY ,0<F3h  
Dim op As T_OPERATION :86luLFm  
Dim mat As T_MODELMATERIAL VqO<+~M,E  
Dim A As Double <cfH '~  
Dim pupilDiam As Double j2{,1hj  
Dim eID As Long }^ Ua  
Dim parID As Long Z\gg<Q  
Dim count As Integer J:-TINeB  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double Q3'B$,3O^  
Dim tlens As Double, nlens As Double RzY`^A6G6  
Dim curv As Double, conic As Double 1KIq$lG{ E  
Dim ok As Long z:Zn.e*$b  
7s fuju(  
Sub Main L};;o+5uJD  
U37?P7i's  
    '用户输入对话框 #+ lq7HJ1  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 <1 1Tqb  
        TextBox 220,21,40,21,.TextBox1 'default: 0 ,, H$>r_;  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 T~~$=vP9  
        OKButton 40,91,90,21 vhquHy.qi#  
        CancelButton 190,91,90,21 []N$;~R7  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 `@.s!L(V  
        TextBox 220,49,40,21,.TextBox2 'default: 4 *ZSp9g"Z  
    End Dialog /%q9hI   
    Dim dlg As UserDialog !wb~A0m  
^(m6g&$(  
    ok = Dialog (dlg) 1q233QSW)  
LX?r=_\  
    If ok=0 Then    'cancel button was pressed N5an9r&z(1  
        Print "Execution cancelled." \A\yuJ=  
        End UE#Ni 5  
    End If lbuW*)  
5iI3u 7Mn1  
    'Assign accommodation and pupil diameter & use defaults if field left empty ):\{n8~  
    If dlg.TextBox1 = "" Then _kY[8e5  
        A = 0           'Default accommodation 674oL,  
    Else ch8w'  
        A = CDbl(dlg.TextBox1) 0|>  
    End If Qx,$)|_  
3;l>x/amk  
    If dlg.TextBox2 = "" Then g Wv+i/,  
        pupilDiam = 4   'Default pupil diameter \/4%[Q2QDm  
    Else tD0>(41K  
        pupilDiam = CDbl(dlg.TextBox2) oY6|h3T=Q$  
    End If E+c3KqM  
|tJ%:`DGw  
    Print " " MJ/%$  
    Print "Accommodation = " & A & " Diopters" n]fbV/ x  
    Print "Pupil Diameter = " & pupilDiam & " mm" /uz5V/i0  
<w2NJ ~M^  
    ' Calculate new parameters with accommodation 8\.1m9&r>o  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness `rdfROKv  
898wZ{9  
    Rant = 12.0 - 0.4*A                     'Radius of anterior lens -hR\Y 2?  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens <^'+ ]?  
I \%Lb z  
    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens )W6- h  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens @N_H]6z4  
Qp.!U~  
    tlens = 3.767 + 0.04*A                  'Lens thickness 6F&]Mk]V8  
|Ge/|;.v`  
    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction c@#zjJhW]  
W#\};P  
    'Adjust parameters to account for accommodation "XsY~  
%+B-Z/1}  
    '************************************************************************* s]8J+8 <uO  
    'Aqueous thickness (Position of Lens) K/d &c]  
    '************************************************************************* cBF%])!  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) (Dh;=xG  
    GetCustomElement eID, entity E1ob+h:`d  
7`<? f O  
    parID = FindFullName( "Geometry.Arizona Eye" ) S,9WMti4x  
h:;eh  
    ' Delete any shift(s) in z wR+`("2{r  
    count = 0 V//q$/&8(  
    While GetOperationCount(eID)>count _v=WjN  
        GetOperation eID, count, op 9x^ /kAB  
        If op.Type="ShiftZ" Then :O+b4R+  
            DeleteOperation eID,count m1o65FsY08  
            count=count-1 >8;%F<o2  
        End If x  Bw.M{  
        count=count+1 Y9y*" :&%  
    Wend fvMhq:Bu  
I%C:d#p  
    'Set new shift in r_sl~^* :  
    op.Type = "ShiftZ" 0Ilvr]1a4  
    op.val1 = taq oqHm:u ^2  
    op.parent = parID ;~$ $WU  
    AddOperation eID, op 78~V/L;@S2  
    Print "Set aqueous humor thickness = " & taq-0.55 pz}hh^]t  
+9rbQ? '  
    '************************************************************************* ZLX`[   
    'Radius and conic constant of anterior lens KBHKcFk  
    '************************************************************************* f_2^PF>?  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) p)&\>   
    GetConic eID, entity, curv, conic QGG(I7{-  
2#M:J gWV  
    SetConic eID, entity, 1/Rant, CCant K5rj!*x.o  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant 8B+^vF   
)^#Zg8L  
    '************************************************************************* 6Q.whV%y  
    'Radius and conic constant of posterior lens ?o5#Ve$-X  
    '************************************************************************* <KPx0g?=b  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) Tm.w+@  
    GetConic eID, entity, curv, conic WREGRy  
ms<uYLp  
    SetConic eID, entity, 1/Rpost, CCpost Jd6Q9~z#  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost ^F9zS `Yz2  
#f;1f8yrN  
    '************************************************************************* n7.lF  
    'Lens thickness (Position of posterior lens surface)  Jiylrf`o  
    '************************************************************************* >Nl~"J|]q  
l 8us6  
    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) O[B_7  
,8 ?*U]}  
    ' Delete any z-shift(s) 1U9N8{xg9  
    count = 0 zb,`K*Z{  
    While GetOperationCount(eID)>count !O_^Rn+<2  
        GetOperation eID, count, op ~M1%,]  
        If op.Type="ShiftZ" Then ,?~,"IQyi[  
            DeleteOperation eID,count 8Kkr1}!wd  
            count=count-1 D ,^ U%<`  
        End If pvxqeC9`  
        count=count+1 {j*+:Gj0V  
    Wend *.Hnt\4|  
58U[r)/  
    'Set new z-shift 8k'em/M~  
    op.Type = "ShiftZ" qqre d>K  
    op.val1 = tlens "z4E|s  
    op.parent = parID iqP0=(^m  
    AddOperation eID, op W\Y 4%y}  
    Print "Set lens thickness = " & tlens b?L43t,  
X]%4QIeS  
    '************************************************************************* m]pvJJ@  
    'Lens index of refraction uRhH_c-6C  
    '************************************************************************* |.nWy"L  
    eID = FindMaterial( "Lens" ) u)>*U'bM  
    GetModelMaterial eID, mat B%;+8]  
0k]N%!U  
    mat.Nd = nlens |<icx8hbr  
    SetModelMaterial eID, mat -bQvJ`iF  
    Print "Set lens index of refraction = " & nlens 0_izTke  
(I g *iJ%2  
    '************************************************************************* h0}-1kVT^  
    'Pupil diameter ( h,F{7  
    '************************************************************************* wj~8KHan  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) 6 VDF@V$E  
 ]^%3Y  
    'Adjust pupil diameter (trimming volume inner hole)  /t P  
K*RRbtb  
    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" Ut@)<N  
n&&y\?n  
    ' Adjust pupil location to just in front of the lens P~>nlm82]  
    parID = FindFullName( "Geometry.Arizona Eye" ) +O6@)?pI  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) "<b84?V5  
    count = 0 m!if_Iq  
    While GetOperationCount(eID)>count !OemS 7{  
        GetOperation eID, count, op N`fY%"5U>  
        If op.Type="ShiftZ" Then UQr+\ u  
            DeleteOperation eID,count 1-<Xi-=^{t  
            count=count-1 /m:}rD  
        End If VQ`O;n6/`  
        count=count+1 2V 'Tt3  
    Wend |3@]5f&  
    op.Type = "ShiftZ" _: x$"i  
    op.val1 = taq-0.01 =B2=UF  
    op.parent = parID ZrBxEf$f  
    AddOperation eID, op #k, kpL<a  
b2H6}s"=w  
    Print "Set pupil diameter = " & pupilDiam 4 -W?u51"  
~o$=(EC  
    'Update AZ Eye subassembly Description cd#TKmh7re  
    eID = FindFullName( "Geometry.Arizona Eye" ) SNFz#*  
    GetEntity eID, entity Stpho4+/y  
    entity.Description = "Accommodation = " & A & "D" 7#QH4$@1P  
    SetEntity eID, entity c:5BQr '  
f}4h}Cq  
    Update *z~Y*Q0  
    Print "DONE!" O;"%z*g.  
     I&0yUhn  
End Sub =?hlgQ  
5E8P bV-l  
如果屈光度是4,光瞳直径是4,则会输出如下数据: ^&%?Q_]  
wAYc)u#  
Accommodation = 4 Diopters zQJbZ=5Bu"  
Pupil Diameter = 4 mm Qfi5fp=f  
Set aqueous humor thickness = 2.81 oY: "nE  
Set anterior lens radius = 10.4 and conic constant = -2.375869 7[\B{N9&W  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 @VAhmYz  
Set lens thickness = 3.927 |v&&%>A2  
Set lens index of refraction = 1.42672 xPv&(XZR  
Set pupil diameter = 4 ),eiJblH  
DONE!
]]4E)j8  
umeb&\:8S-  

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