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

{4G/HW28  
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。 - |g"q|  
1^}I?PbqV  
模型 LnI  
$ItjVc@U  
模型的定义如表1种所示,由半径、圆锥常数、折射率、阿贝数、到下一面的距离等一系列表面组成。一些参数由屈光度(A)来决定。 Ww2@!ng  
Table 1. AZ眼睛模型的定义
Z_\p8@3aH  
9{toPED  
在FRED中使用0屈光度来创建的,光瞳加在了透镜的前面。材料是创建一个新的材料并选择类型“Model Material”,输入的参数是nd和vd. Q5+1'mzAB  
YX0ysE*V:&  
光源 5I622d  
{ qNPhi  
多个光源定义来分析该模型的不同特性。图1显示了所以的光源和提示信息告诉您他们可以用来做什么。 P=QxfX0B  
2*|T)OA`m,  
图1. 光源和提示信息使用
a#YK1n[!  
Hc)z:x;Sj  
除了“Letter F”之外的所有光源的光线位置设定在了孔径光阑位置处,并增加了pre-propagation distance= -8。尽管光线在光瞳处创建,规定的传输方向相对于光线位置在pre-propagation distance之后。这意味着光束沿着Z轴在眼睛的前面以平行光入射,而不是在光瞳处入射。 ky2 bj}"p9  
lK0ny>RB  
在往下看是内置的脚本用来修改屈光度,使其为4(250mm),光源“Letter F”在视网膜处生成一个字母为F的图像。绿色的光线聚焦的非常好而红色和蓝色光线有一点的模糊。使用Positions Spot Diagram分析工具来观察最为合适。 Lgg,K//g  
图2. 字母F光源的设定方法光 _QPqF{iI  
ZSC*{dD$E  
图3. 字母F在视网膜上位置点列图
P8tdT3*6/  
54+(o6E<  
视网膜的散射 BzzC|  
VfX^iG r  
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。 4<y   
mlnF,+s  
图4. 视网膜朗伯散射设定
3 jZMXEG)  
>HP `B2Q H  
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。 s,HbW%s  
95l)s],  
图5. 视网膜重点采样规格设定
u^" I3u8$  
EuK}L[Kl  
脚本 ~KBa-i%o  
;CYoc4e  
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: #De>EQ%  
图6. 用户对话框的创建与编辑
G;Li!H  
图7. 用户对话框编辑器
zBF~:Uc`B  
p['RV  
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。 l4bytI{63  
余下的脚本计算与屈光度有关的所有参数。 36 "n7  
xE/?ncTK^  
分析 e97G]XLR  
|N.2iN:  
屈光度为4,光瞳直径为4mm,字母F点在视网膜上所成的像。 7o E0;'  
图7. 字母F在视网膜上颜色分析
O=B =0  
)PX VR T  
脚本代码 C8U3+ s  
`Ij@;=(  
Option Explicit     'Remove this to enable non-dimensioned variables to be used. ma.84~m  
"4N&T#  
Dim entity As T_ENTITY 1EyN |m|  
Dim op As T_OPERATION }Q\%tZC#T  
Dim mat As T_MODELMATERIAL &@0~]\,D7  
Dim A As Double "r9Rr_, >  
Dim pupilDiam As Double 82r8K|L.<y  
Dim eID As Long a3@E`Z  
Dim parID As Long Q Be6\oq  
Dim count As Integer qE[S>/R"  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double Ds9)e&yYrb  
Dim tlens As Double, nlens As Double K d&/9<{>  
Dim curv As Double, conic As Double +jm,nM9  
Dim ok As Long 0dch OUj  
Y|>dS8f;4  
Sub Main l/.{F;3F  
bZqTT~'T  
    '用户输入对话框 ij" ~]I  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 a=z] tTs4  
        TextBox 220,21,40,21,.TextBox1 'default: 0 e;]tO-Nu  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 ['d9sEv.  
        OKButton 40,91,90,21 E/;t6& 6  
        CancelButton 190,91,90,21 Hfcpqa  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 Pfd1[~,  
        TextBox 220,49,40,21,.TextBox2 'default: 4 |xO*!NR  
    End Dialog g'"~'  
    Dim dlg As UserDialog >!963>DR  
E&M(QX5  
    ok = Dialog (dlg) d$t"Vp  
Fr9/TI  
    If ok=0 Then    'cancel button was pressed 70'OS:J=\  
        Print "Execution cancelled." ~ao:9 ynY  
        End $y(;"hy  
    End If PX:#+bq1  
djd/QAfSC  
    'Assign accommodation and pupil diameter & use defaults if field left empty 6u[fCGi%  
    If dlg.TextBox1 = "" Then ]C_+u_9  
        A = 0           'Default accommodation !/FRL<mp  
    Else #:K=zV\  
        A = CDbl(dlg.TextBox1) kDmm  
    End If I/E9:  
7J'%;sH  
    If dlg.TextBox2 = "" Then 0vY_  
        pupilDiam = 4   'Default pupil diameter p3s i\Fm!  
    Else I^NDJdxd  
        pupilDiam = CDbl(dlg.TextBox2) I"Oq< _  
    End If 2t= = <x  
c=m'I>A  
    Print " "  RD$:.   
    Print "Accommodation = " & A & " Diopters" 'eM0i[E+`  
    Print "Pupil Diameter = " & pupilDiam & " mm" r!:yUPv  
"{q#)N  
    ' Calculate new parameters with accommodation c=! >m  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness w~lH2U'k}  
7;>|9k  
    Rant = 12.0 - 0.4*A                     'Radius of anterior lens 4G&`&fff]  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens S?~0)EXj(  
>eJ <-3L;  
    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens 5.rAxdP  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens I G1];vX  
,H=k5WA4m  
    tlens = 3.767 + 0.04*A                  'Lens thickness  N' hT  
;ALWL~Xm  
    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction MAh1tYs4D  
(x=$b(I  
    'Adjust parameters to account for accommodation Q}BMvR 9w  
ImXYI7PL  
    '************************************************************************* b8WtNVd  
    'Aqueous thickness (Position of Lens) 1@]&iZ]  
    '************************************************************************* d NACE*g;q  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) uwwR$ (\7  
    GetCustomElement eID, entity YxF@1_g  
(r|m&/  
    parID = FindFullName( "Geometry.Arizona Eye" ) T#!>mL|9|  
t G_4>-Y#w  
    ' Delete any shift(s) in z t"=5MaQk-  
    count = 0 wZvv5:jKpu  
    While GetOperationCount(eID)>count Wjb_H (D  
        GetOperation eID, count, op b3A0o*  
        If op.Type="ShiftZ" Then 35\ |#2qw6  
            DeleteOperation eID,count $1f2'_`8~  
            count=count-1 p-4$)w~6i  
        End If K%q5:9m  
        count=count+1 '*J+mZtN  
    Wend Gwd38  
qb>ULP0  
    'Set new shift in (< +A  w7  
    op.Type = "ShiftZ" 4@9Pd &I  
    op.val1 = taq {npm9w<;  
    op.parent = parID e]4$H.dP  
    AddOperation eID, op bzr2Zj{4  
    Print "Set aqueous humor thickness = " & taq-0.55 oE ' P  
VLuHuih  
    '************************************************************************* t2[/eM.G  
    'Radius and conic constant of anterior lens ^exU]5nvz  
    '************************************************************************* uw;Sfx,s  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) 4H{t6t@-:  
    GetConic eID, entity, curv, conic C;W@OS-;  
s6H.Q$3L  
    SetConic eID, entity, 1/Rant, CCant wQ33Gc  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant g=Z52y`N<  
EBy7wU`S  
    '************************************************************************* Ht[$s40P  
    'Radius and conic constant of posterior lens )vW'g3u_  
    '************************************************************************* V}y]<  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) Qs1p  
    GetConic eID, entity, curv, conic |A&;m}(Mt  
P$E iD+5#z  
    SetConic eID, entity, 1/Rpost, CCpost  ?eS;Yc  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost b-u@?G|<  
JduO^Fit  
    '************************************************************************* 9c@M(U@Yh  
    'Lens thickness (Position of posterior lens surface) E)-;sFz  
    '************************************************************************* .S//T/3O]Q  
JL M Xkcc  
    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) ~F"S]  
-1Q24jrO-  
    ' Delete any z-shift(s) <h -)zI  
    count = 0 UoxlEec  
    While GetOperationCount(eID)>count [F6 )Z[uG  
        GetOperation eID, count, op {4g';  
        If op.Type="ShiftZ" Then 8~Kq "wrbu  
            DeleteOperation eID,count 2uj .*  
            count=count-1 <K CI@  
        End If KA2>[x2  
        count=count+1 '+9<[]  
    Wend 9pLe8D  
r#zcl)rbU  
    'Set new z-shift UT;%I_i!'  
    op.Type = "ShiftZ" ;\K]~  
    op.val1 = tlens t3)6R(JC  
    op.parent = parID FX!KX/OE)  
    AddOperation eID, op 6 byeO&d  
    Print "Set lens thickness = " & tlens h*Fv~j'p  
2 7)If E  
    '************************************************************************* S~/2Bw!2  
    'Lens index of refraction ,U""m7   
    '************************************************************************* =Kj{wA O  
    eID = FindMaterial( "Lens" ) gX" -3w  
    GetModelMaterial eID, mat )+N{D=YM  
3Q,&D'];[  
    mat.Nd = nlens '8 .JnCg  
    SetModelMaterial eID, mat T=PqA)Ym  
    Print "Set lens index of refraction = " & nlens wO]e%BTO  
}ny7LQ  
    '************************************************************************* 4X^$"lM  
    'Pupil diameter OlT8pG5Oa  
    '************************************************************************* ]Thke 4  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) ny KfM5s_  
vn}m-U XA*  
    'Adjust pupil diameter (trimming volume inner hole) 8:0/Cj  
8\s#law  
    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" }uma<b  
I8XP`Ccq  
    ' Adjust pupil location to just in front of the lens  E0!d c  
    parID = FindFullName( "Geometry.Arizona Eye" ) e]VW\ 6J&  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) ,sitOy}ks  
    count = 0 ==Egy:<:Q  
    While GetOperationCount(eID)>count G2|jS@L#  
        GetOperation eID, count, op {py%-W  
        If op.Type="ShiftZ" Then B@*b 9  
            DeleteOperation eID,count ]W;6gmV  
            count=count-1 YrnC'o`  
        End If q8P&rMwy  
        count=count+1 Erw1y,mF  
    Wend UOb` @#  
    op.Type = "ShiftZ" #G#gc`S-,  
    op.val1 = taq-0.01 8&U Mmbgy  
    op.parent = parID ?z>J7 }w*=  
    AddOperation eID, op d.? }>jl  
NK qI x  
    Print "Set pupil diameter = " & pupilDiam x3i}IC  
=mXC,<]  
    'Update AZ Eye subassembly Description 4'z)J1M  
    eID = FindFullName( "Geometry.Arizona Eye" ) u\Cf@}5(  
    GetEntity eID, entity - VJx)g  
    entity.Description = "Accommodation = " & A & "D" 3O,nNt;L{  
    SetEntity eID, entity {wC*61@1  
opH!sa@U  
    Update @ eJ8wf]  
    Print "DONE!" ?9t4>xKn  
     ;qaPK2 a8  
End Sub @<P2di  
H^|TV]^;N  
如果屈光度是4,光瞳直径是4,则会输出如下数据:  igo9~.  
4Kch=jt4#  
Accommodation = 4 Diopters <\O+  
Pupil Diameter = 4 mm S OI=~BGd)  
Set aqueous humor thickness = 2.81 Bf*>q*%B{  
Set anterior lens radius = 10.4 and conic constant = -2.375869 F q~uuQ  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 {.2\}7.c  
Set lens thickness = 3.927 0g[ %)C  
Set lens index of refraction = 1.42672 IW~wO  
Set pupil diameter = 4 Jw _>I  
DONE!
G:1d6[Q5{  
;mEn@@{  

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