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 2021-10-22 09:55

Arizona眼睛模型

简介 ".2K9j7$  
j.?:Gaab?#  
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。 x!7yU_ls`  
m9$:9yRm  
模型 8QgA@y"  
xN->cA$A  
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。 L&2u[ml  
$n=lsDnhQ  
Table 1. AZ眼睛模型的定义
HD`>-E#  
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. Un=a fX?j  
nS.G~c|  
光源 n2-0.Er  
`^F: -  
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。 ?Hz2-Cn  
iw]k5<qKj  
+c,[ Q  
图1. 光源和提示信息使用
m\0cE1fir  
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。 *YV S|6bs  
C".1+Um  
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。 W:s@L#-  
Ww9;UP'G  
图2. 字母F光源的设定方法光 I<\ '%  
*> 3Qd7  
图3. 字母F在视网膜上位置点列图
$~u.Wq  
视网膜的散射 gT52G?-  
K'b*A$5o  
在散射文件中,有一个名为“Retina surface”的72%的反射型朗伯散射,它为视网膜的散射提供了一个粗略的近似。为了模拟来自视网膜的散射,改变自定义元件“Eye ball” 下的视网膜的表面从“halt all” 到”Allow All”。并使几何中“plane”可追迹。 U@lV  
wz(K*FP  
|"7Pv skT  
图4. 视网膜朗伯散射设定
7nE"F!d+0  
注意在视网膜的表面有散射重点采样规格定义,在“Scatter”标签的底部可获取该信息。“toward pupil”指定散射光朝向光瞳,半角度10度。 F 1W+o?B  
^$?qT60%d|  
C3;[e0.1b  
图5. 视网膜重点采样规格设定
{[#(w75R{  
脚本 #6> 6S;Ib  
5G*II_j  
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: gQVBA %  
fj']?a!m  
图6. 用户对话框的创建与编辑
.Ao0;:;(2-  
图7. 用户对话框编辑器
)iE"Tl  
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。 |ng%PQq)  
余下的脚本计算与屈光度有关的所有参数。 XAic9SNu;  
Z5)eREi=  
分析 @z,*K_AKr  
~l4f{uOD>]  
屈光度为4,光瞳直径为4mm,字母F点在视网膜上所成的像。 `lCuU~~ag  
U6j/BJT"  
图7. 字母F在视网膜上颜色分析
x7ATI[b[  
脚本代码 "dCzWFet  
&^QPkX@p  
Option Explicit     'Remove this to enable non-dimensioned variables to be used. ?Myh 7  
pM$ @m]  
Dim entity As T_ENTITY TipHV;|e  
Dim op As T_OPERATION /&s}<BMHU  
Dim mat As T_MODELMATERIAL F @SG((`  
Dim A As Double ,x#ztdvr  
Dim pupilDiam As Double JeQ[qQ  
Dim eID As Long "kSwa16O  
Dim parID As Long 4F#%f#"  
Dim count As Integer gA:TL{X0  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double v*TeTA %  
Dim tlens As Double, nlens As Double zy)i1d  
Dim curv As Double, conic As Double {BOLP E-  
Dim ok As Long (_8#YyW#  
0s%6n5>  
Sub Main 8&(-8  
zixE Mi[8  
    '用户输入对话框 Jt=>-Spj  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 iJnh$jo  
        TextBox 220,21,40,21,.TextBox1 'default: 0 TmP8 q  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 +VOb  
        OKButton 40,91,90,21 &9P<qU^N)  
        CancelButton 190,91,90,21 /$`;r2LG  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 uWc:jP  
        TextBox 220,49,40,21,.TextBox2 'default: 4 TA;,>f*  
    End Dialog j%xBo:  
    Dim dlg As UserDialog [j0w\{  
<94WZ?{p  
    ok = Dialog (dlg) u4"r>e6 _B  
U$J5r+>  
    If ok=0 Then    'cancel button was pressed rm|7 [mK  
        Print "Execution cancelled." l>Av5g)  
        End el*9 Ih  
    End If FAtWsk*pgY  
%$9:e J?  
    'Assign accommodation and pupil diameter & use defaults if field left empty 9ECS,r*B  
    If dlg.TextBox1 = "" Then ,y.3Fe  
        A = 0           'Default accommodation q$>_WF#||  
    Else mQ,{=C=D  
        A = CDbl(dlg.TextBox1) Wem?{kx0  
    End If lU$X4JBzS  
!%62Phai  
    If dlg.TextBox2 = "" Then I#c(J  
        pupilDiam = 4   'Default pupil diameter 6ZgNHARS  
    Else Czh8zB+r  
        pupilDiam = CDbl(dlg.TextBox2) G"Pj6QUva  
    End If e6m1NH4,  
@_O3&ZK  
    Print " " ?`i|" y #  
    Print "Accommodation = " & A & " Diopters" 2Iz fP;V?  
    Print "Pupil Diameter = " & pupilDiam & " mm" 32y[  
=ZMF]|  
    ' Calculate new parameters with accommodation ZgBckb  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness s01$fFJgO  
m3"c (L`B  
    Rant = 12.0 - 0.4*A                     'Radius of anterior lens _LsYMUe  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens 6o(lObfo  
bL MkPty  
    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens %*p^$5L<  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens i-"<[*ePd  
Zh? V,39  
    tlens = 3.767 + 0.04*A                  'Lens thickness @>Ek'~m  
eoL0^cZj  
    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction ~Jxlj(" 0(  
P2QRvn6v  
    'Adjust parameters to account for accommodation ](n69XX_  
8J^d7uC  
    '************************************************************************* W U0UG$o`  
    'Aqueous thickness (Position of Lens) ' tSnH&c  
    '************************************************************************* v?{vg?vI  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) APOea  
    GetCustomElement eID, entity w'XSb.\)_m  
n4R]+&*  
    parID = FindFullName( "Geometry.Arizona Eye" ) UL ck  
x3_,nl  
    ' Delete any shift(s) in z 9JXhHAxD  
    count = 0 K"I{\/x@  
    While GetOperationCount(eID)>count > XZg@?Iw  
        GetOperation eID, count, op _-(z@  
        If op.Type="ShiftZ" Then \`&xprqAw  
            DeleteOperation eID,count d}pGeU'  
            count=count-1 qs "s/$  
        End If 5@iy3olP  
        count=count+1 uzO {{S-  
    Wend V"BVvSNu  
v$Dh.y  
    'Set new shift in VAt>ji7c  
    op.Type = "ShiftZ" 03] r*\  
    op.val1 = taq (w}r7`n  
    op.parent = parID R'r|E_  
    AddOperation eID, op WEps.]s  
    Print "Set aqueous humor thickness = " & taq-0.55 dZ-Ny_@&  
t3 K>\ :  
    '************************************************************************* (+@faP   
    'Radius and conic constant of anterior lens ItMl4P`|  
    '************************************************************************* Dn: Yi8=  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) 83B\+]{hD  
    GetConic eID, entity, curv, conic LuLy6]6D;  
D`8E-Bq  
    SetConic eID, entity, 1/Rant, CCant rdFs?hO  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant F6~b#Jz&i  
q~mcjbLz  
    '************************************************************************* 1X Q87~  
    'Radius and conic constant of posterior lens QZWoKGd}+  
    '************************************************************************* $`ON!,oa  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) RLv&,$$0  
    GetConic eID, entity, curv, conic Cx$9#3\  
sek6+#|=  
    SetConic eID, entity, 1/Rpost, CCpost p$B)^S%0i  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost Xx=K?Z?3.  
0H; "5  
    '************************************************************************* T..-)kL+p  
    'Lens thickness (Position of posterior lens surface) Dy98[cL  
    '************************************************************************* H+nr5!`kz  
fQ^h{n  
    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) CzK%x?~]  
FW/6{tm  
    ' Delete any z-shift(s) %L.lkRs  
    count = 0 H 3W_}f  
    While GetOperationCount(eID)>count |.^^|@+  
        GetOperation eID, count, op %`bLmfm  
        If op.Type="ShiftZ" Then 7&#'c8]/qh  
            DeleteOperation eID,count G1,Ro1  
            count=count-1 bBd*}"v^"  
        End If rHH#@ Zx  
        count=count+1 c>M_?::)0  
    Wend C,V|TF.i2  
^XtHF|%0T  
    'Set new z-shift /M5=tW#e  
    op.Type = "ShiftZ" y[TaM9<  
    op.val1 = tlens =9#i<te  
    op.parent = parID pIk4V/ fy  
    AddOperation eID, op ':5U&  
    Print "Set lens thickness = " & tlens #Lu4OSM+  
hj%}GP{{  
    '************************************************************************* LPtx|Sx![  
    'Lens index of refraction u0<d2Y  
    '************************************************************************* 5;r({ J  
    eID = FindMaterial( "Lens" ) jJiCF,m  
    GetModelMaterial eID, mat <h)deB+}  
Tom}sFl][  
    mat.Nd = nlens :FEd:0TS  
    SetModelMaterial eID, mat '5&B~ 1&  
    Print "Set lens index of refraction = " & nlens Nj! R9N  
5|{  t+u  
    '************************************************************************* QSlf=VK*y  
    'Pupil diameter g;| n8]  
    '************************************************************************* y}.y,\S0  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) ?)i6:76(  
s2,`eV  
    'Adjust pupil diameter (trimming volume inner hole) -Hl\j (D7  
?etj.\q6  
    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" LGdf_M-f  
\J#I}-a&j  
    ' Adjust pupil location to just in front of the lens #)Id J]  
    parID = FindFullName( "Geometry.Arizona Eye" ) >B|ofwm*  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) 67EDkknt  
    count = 0 ~cWLu5  
    While GetOperationCount(eID)>count #CBo  
        GetOperation eID, count, op *GY,h$Ul  
        If op.Type="ShiftZ" Then @DjG? yLK$  
            DeleteOperation eID,count 7]0\[9DyJ  
            count=count-1 |wl")|b%  
        End If *;~{_Disz  
        count=count+1 hU=f?jo/  
    Wend &QHA_+88W  
    op.Type = "ShiftZ" &AkzSgP  
    op.val1 = taq-0.01 y2d_b/  
    op.parent = parID #oS  
    AddOperation eID, op f]^J,L9qz  
cfF-e93T  
    Print "Set pupil diameter = " & pupilDiam 'JXN*YO  
e3bAT.P  
    'Update AZ Eye subassembly Description JN9HT0  
    eID = FindFullName( "Geometry.Arizona Eye" ) l7FZ;%&  
    GetEntity eID, entity ]MBJ"1F  
    entity.Description = "Accommodation = " & A & "D" X]f#w  
    SetEntity eID, entity \p_8YC  
~=aI2(b  
    Update QyBK*uNdV  
    Print "DONE!" Amq8q  
     bC>yIjCTn  
End Sub 5}(YMsUb  
|Cxip&e>  
如果屈光度是4,光瞳直径是4,则会输出如下数据: U~QCN[gh  
5#A1u Nb  
Accommodation = 4 Diopters n$Oky-P"  
Pupil Diameter = 4 mm Qc)RrqYNGF  
Set aqueous humor thickness = 2.81 }@t'rK[  
Set anterior lens radius = 10.4 and conic constant = -2.375869 'FvhzGn9Q  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 Jh hT7\h(  
Set lens thickness = 3.927 g#bfY=C  
Set lens index of refraction = 1.42672 4h0jX 9  
Set pupil diameter = 4 J0Rz.=Y  
DONE! 4 w/t$lR  
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