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

DQ8/]Z{H  
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。 h3 H Udu  
Qhj']>#g  
模型 w>B}w  
XHA|v^  
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。 qiet<F  
Table 1. AZ眼睛模型的定义
'u.Dt*.Uq  
OP\jO DX  
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. :|(YlNUv  
Nk@-yZ@,8  
光源 |pHlBzHj  
K^!#;,0  
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。 A l;a~45  
N5K(yY_T  
图1. 光源和提示信息使用
N'y<<tTA  
FF#Aq  
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。 L ,R}l0kc  
?jR#txR  
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。 ( K[e=0Rf  
图2. 字母F光源的设定方法光 ~ g!!#ad  
s={>{,E  
图3. 字母F在视网膜上位置点列图
6 5zx<  
62ru%<x=  
视网膜的散射 4 Y=0>FlY0  
i1x4$}  
在散射文件中,有一个名为“Retina surface”的72%的反射型朗伯散射,它为视网膜的散射提供了一个粗略的近似。为了模拟来自视网膜的散射,改变自定义元件“Eye ball” 下的视网膜的表面从“halt all” 到”Allow All”。并使几何中“plane”可追迹。 ,<Cl^ ^a,  
>\K=)/W2  
图4. 视网膜朗伯散射设定
Y-})/zFc  
4AL,=C3  
注意在视网膜的表面有散射重点采样规格定义,在“Scatter”标签的底部可获取该信息。“toward pupil”指定散射光朝向光瞳,半角度10度。 z9 0JZA  
J3y _JoS  
图5. 视网膜重点采样规格设定
jvQ^Vh!mC  
_Yo)m |RaB  
脚本 +7%?p"gEY\  
bYLYJ`hH<R  
内置脚本使用对话框显示屈光度和光瞳直径的数值设置。使用FRED Basic脚本创建和使用对话框非常容易。图6显示了如何获取用户自定义对话框,如下图所示: \SmsS^z(]  
图6. 用户对话框的创建与编辑
HKbV@NW  
图7. 用户对话框编辑器
CE M4E  
A o* IshVh  
如果“OK”按钮按下,将会核对对话框下面的代码行,如果点击取消则脚本终止。然后输入的参数赋予变量,如果此处是保留为空白,则使用默认值。因此,如果没有值输入并点击“OK”按钮,则脚本是以屈光度为0,光瞳直径为4mm来运行的。 (^W}uDPCB  
余下的脚本计算与屈光度有关的所有参数。 S$SCW<LuN  
AO`@ &e]o  
分析 hbYstK;]Z  
zx<t{e7  
屈光度为4,光瞳直径为4mm,字母F点在视网膜上所成的像。 8G)~#;x1  
图7. 字母F在视网膜上颜色分析
>e;jGk?-  
(_#E17U)_  
脚本代码 346 z`5  
97 SS0J  
Option Explicit     'Remove this to enable non-dimensioned variables to be used. T[OI/ WuK  
wDi/oH/H  
Dim entity As T_ENTITY 5 v.&|[\k  
Dim op As T_OPERATION P8=|#yCi  
Dim mat As T_MODELMATERIAL PW@ :fM:q  
Dim A As Double l'm|**  
Dim pupilDiam As Double ,W+=N"`a'  
Dim eID As Long e,#w* |  
Dim parID As Long sR$abN+u  
Dim count As Integer gm5%X'XL  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double q/ :]+  
Dim tlens As Double, nlens As Double VEa"^{,w  
Dim curv As Double, conic As Double &(<>} r  
Dim ok As Long ]4B;M Ym*  
t$qIJt$  
Sub Main Mm,\e6#*  
kj|Oj+&  
    '用户输入对话框 i5(qJ/u  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 CSjd&G *ZB  
        TextBox 220,21,40,21,.TextBox1 'default: 0 3KqRw (BK  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 An>ai N]  
        OKButton 40,91,90,21 t0cS.hi  
        CancelButton 190,91,90,21 i'CK/l.H  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 r=.@APZB  
        TextBox 220,49,40,21,.TextBox2 'default: 4 k t`ln  
    End Dialog _fgsHx>l7  
    Dim dlg As UserDialog FLJ&ZU=s  
:BR_%$  
    ok = Dialog (dlg) OE[7fDe'  
A%EhRAy  
    If ok=0 Then    'cancel button was pressed \$Ky AWrZi  
        Print "Execution cancelled." 0-OKbw5%=b  
        End [,st: Y  
    End If O_s /BoB@  
JkR%o #>5  
    'Assign accommodation and pupil diameter & use defaults if field left empty V O1   
    If dlg.TextBox1 = "" Then @Wd (>*"zw  
        A = 0           'Default accommodation {pi_yr3  
    Else 7gLk~*  
        A = CDbl(dlg.TextBox1) w)K547!00  
    End If XU<owk  
":e6s co  
    If dlg.TextBox2 = "" Then )M.g<[= ^  
        pupilDiam = 4   'Default pupil diameter ,c&t#mu*0  
    Else U*N{H$ACuR  
        pupilDiam = CDbl(dlg.TextBox2) l %zbx"%x  
    End If <%^WZ:c  
V!*1F1  
    Print " " |H8C4^1Rq  
    Print "Accommodation = " & A & " Diopters" b!MN QGs  
    Print "Pupil Diameter = " & pupilDiam & " mm" d8 ~%(I9  
GLub5GrxR  
    ' Calculate new parameters with accommodation =MJRQ V67  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness AzzHpfv,  
VJA/d2Oys  
    Rant = 12.0 - 0.4*A                     'Radius of anterior lens F@z%y'5 Z*  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens *Q2 oc:6  
f3vl=EA4|  
    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens b&,Z mDJh  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens a{^ 2c!  
&RuTq6)r  
    tlens = 3.767 + 0.04*A                  'Lens thickness TqS s*as5  
08AD~^^  
    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction lZkJ<*z#  
( !m6>m2  
    'Adjust parameters to account for accommodation c#u_%*  
=>o !   
    '************************************************************************* 3GL?&(eU;  
    'Aqueous thickness (Position of Lens) "IpbR  
    '************************************************************************* p4\sKF8-  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) s 7%iuP  
    GetCustomElement eID, entity REcKfJTj  
1W.oRD&8j/  
    parID = FindFullName( "Geometry.Arizona Eye" ) ~T9QpL1OJ  
9I5AYa?  
    ' Delete any shift(s) in z >^W6'Q$P<  
    count = 0 TWRnty-C  
    While GetOperationCount(eID)>count &&jQ4@m}j  
        GetOperation eID, count, op 9%R"(X)  
        If op.Type="ShiftZ" Then fwx^?/5j  
            DeleteOperation eID,count `X ()"Qw  
            count=count-1 j,%i.[8S  
        End If 2!9W:I7  
        count=count+1 eC 2~&:$L  
    Wend Gys-Im6>~@  
7[L%j;)bw  
    'Set new shift in m'G=WO*%  
    op.Type = "ShiftZ" f `b6E J  
    op.val1 = taq fMHw=wJQ  
    op.parent = parID EHl~y=9  
    AddOperation eID, op WcXNc`x  
    Print "Set aqueous humor thickness = " & taq-0.55 5KTFf6Uq  
%y_pF?2@q  
    '************************************************************************* xU{0rM"  
    'Radius and conic constant of anterior lens +|<bb8%  
    '************************************************************************* D;48VK/Q  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) >#;_Ebl@  
    GetConic eID, entity, curv, conic L*p7|rq$"  
G^;]]Ji"  
    SetConic eID, entity, 1/Rant, CCant &{#6Z  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant Jp8,s%  
cN2Pl%7  
    '************************************************************************* F }F{/  
    'Radius and conic constant of posterior lens :vS/Lzk  
    '************************************************************************* ]A+t@/k  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) ]$.w I~J%  
    GetConic eID, entity, curv, conic |Ul4n@+2  
::GW  
    SetConic eID, entity, 1/Rpost, CCpost [%/B"w Tt  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost vUL@i'0&o  
ht+wi5b  
    '************************************************************************* (KvN#d 1\  
    'Lens thickness (Position of posterior lens surface) 6/'X$}X  
    '************************************************************************* %3=T7j  
A??a:8id^  
    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) y+7+({w<  
]|IeE!6  
    ' Delete any z-shift(s) fI.X5c>WK  
    count = 0 /L]@k`.q@  
    While GetOperationCount(eID)>count P $r!u%W  
        GetOperation eID, count, op g<w1d{Td  
        If op.Type="ShiftZ" Then <h~uGBS"  
            DeleteOperation eID,count I;<__  
            count=count-1 iH dX  
        End If wXYT(R  
        count=count+1 R(}!gv}s  
    Wend =8]Ru(#Ig  
DU5rB\!.~  
    'Set new z-shift ;?-{Uk  
    op.Type = "ShiftZ" plzwk>b_  
    op.val1 = tlens G!D~*B9 G  
    op.parent = parID UpiZd/K  
    AddOperation eID, op A~s6~  
    Print "Set lens thickness = " & tlens @te}Asv  
,&@FToR  
    '************************************************************************* QdD@[  
    'Lens index of refraction a6d|Ps.\!  
    '************************************************************************* daf-B-  
    eID = FindMaterial( "Lens" ) `"xzC $  
    GetModelMaterial eID, mat '&]6(+I>  
zR=g<e1xe  
    mat.Nd = nlens IpKI6[2{`f  
    SetModelMaterial eID, mat %yR 80mn8  
    Print "Set lens index of refraction = " & nlens # ?u bvSdU  
kc@ \AZb  
    '************************************************************************* *JWPt(bnI  
    'Pupil diameter %2?"x*A  
    '************************************************************************* lZ,$lZg9Z  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) SS;'g4h\6  
*@YQr]~ ;  
    'Adjust pupil diameter (trimming volume inner hole) n*~#]%4  
k6;pi=sYNW  
    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder"  Kc3/*eu;  
|g\CS4$  
    ' Adjust pupil location to just in front of the lens 3 "|A5>Vo  
    parID = FindFullName( "Geometry.Arizona Eye" ) @d ^MaXp_P  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) ?J"Y4,{  
    count = 0 ^<aj~0v  
    While GetOperationCount(eID)>count OJ7y  
        GetOperation eID, count, op grDz7\i:  
        If op.Type="ShiftZ" Then #vR5a}BAk  
            DeleteOperation eID,count a7]Z_Gk  
            count=count-1 +J !1z  
        End If NL"w#kTc()  
        count=count+1 Yp $@i20  
    Wend 'f.5hX(Y  
    op.Type = "ShiftZ" n+'s9  
    op.val1 = taq-0.01 Ap}`Q(.  
    op.parent = parID ;|CG9|p  
    AddOperation eID, op r"lh\C|  
"W"r0"4  
    Print "Set pupil diameter = " & pupilDiam kChCo0Q>1  
,^T0!k$  
    'Update AZ Eye subassembly Description L%.=Sb mS  
    eID = FindFullName( "Geometry.Arizona Eye" ) 1a#R7chl  
    GetEntity eID, entity c+<gc:#jy  
    entity.Description = "Accommodation = " & A & "D" wY7+E/  
    SetEntity eID, entity {6wy}<ynC+  
ZD8E+]+  
    Update V##TG0  
    Print "DONE!" ,\PTn7_  
     #@L<<Q8}  
End Sub ^cojETOv  
u%CJjy  
如果屈光度是4,光瞳直径是4,则会输出如下数据: Uetna!ABB  
z|N*Gs>,  
Accommodation = 4 Diopters .@Jos^rxgJ  
Pupil Diameter = 4 mm 3>^S6h}o  
Set aqueous humor thickness = 2.81 0h"uJco,  
Set anterior lens radius = 10.4 and conic constant = -2.375869 ,Q8h#0z r  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 I#CS;Yh95  
Set lens thickness = 3.927 Lor__ K  
Set lens index of refraction = 1.42672 /oU$TaB>(  
Set pupil diameter = 4 tkhEjTZ  
DONE!
)B Xl|V,  
h56s~(?O  

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