-
UID:317649
-
- 注册时间2020-06-19
- 最后登录2025-12-11
- 在线时间1894小时
-
-
访问TA的空间加好友用道具
|
简介 2KVMQH`B9 Qr]xj7\@i 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。 mqgA Z7RGOZQ}G 模型 fkE4[X7f ~qQSt% 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。 edld(/wu~ 3 EH/6 Table 1. AZ眼睛模型的定义 ETvn$ Jdp 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. =ic"K6mhq D QO~<E6c 光源 Dyv 6K_, ?dMyhU} 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。 @igGfYy (t'hWS D /ysS$!{ 图1. 光源和提示信息使用 5W"&$6vj 除了“Letter F”之外的所有光源的光线位置设定在了孔径光阑位置处,并增加了pre-propagation distance= -8。尽管光线在光瞳处创建,规定的传输方向相对于光线位置在pre-propagation distance之后。这意味着光束沿着Z轴在眼睛的前面以平行光入射,而不是在光瞳处入射。 C9zQ{G i5wXT 在往下看是内置的脚本用来修改屈光度,使其为4(250mm),光源“Letter F”在视网膜处生成一个字母为F的图像。绿色的光线聚焦的非常好而红色和蓝色光线有一点的模糊。使用Positions Spot Diagram分析工具来观察最为合适。 r&sm&4)p-5 1A\Jh3;Q 图2. 字母F光源的设定方法光 (|%YyRaX bM7y}P5`1 图3. 字母F在视网膜上位置点列图 0S8v41i6 视网膜的散射 _mVq9nBEf =9$hZ c 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。 ; (I(TG $YuVM r0kJx$f 图4. 视网膜朗伯散射设定 ,'[L6=# 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。 {n9]ej^
x+Vp& d`]|i:*q 图5. 视网膜重点采样规格设定 #\9sCnb 脚本 ,b;eU[!] w@&g9e6E 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: 5dc24GB>_ :m*r(i3 图6. 用户对话框的创建与编辑 $s$j</.q 图7. 用户对话框编辑器 *Y!'3|T 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。 .ko8`J%%M 余下的脚本计算与屈光度有关的所有参数。 *L_ +rJj, ! Ra.DSL 分析 7A0D[?^xe N-*
^V^V 屈光度为4,光瞳直径为4mm,字母F点在视网膜上所成的像。 Cv7FVl-I Zz!0|-\ 图7. 字母F在视网膜上颜色分析 r;:5P%: 脚本代码 bxX[$q V,t&jgG*
Option Explicit 'Remove this to enable non-dimensioned variables to be used. / J 3 5Y<O Dim entity As T_ENTITY .)Xyzd Dim op As T_OPERATION c(Liwuj Dim mat As T_MODELMATERIAL y9W6e" Dim A As Double b0W~*s [4 Dim pupilDiam As Double +$Q.N{LV Dim eID As Long Y rq-( Dim parID As Long S!!i Dim count As Integer ap|7./yg Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double Y r3h=XY Dim tlens As Double, nlens As Double W
vh3Y,|3 Dim curv As Double, conic As Double Q}ebw Dim ok As Long >y&Db Vgy}0pCl Sub Main s;oDwT1 6zuWG0t '用户输入对话框 -h=K]Y{` Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 _@U?;73"5 TextBox 220,21,40,21,.TextBox1 'default: 0 vrVb/hhG Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 :N!Fe7H, OKButton 40,91,90,21 *n9t~t6GHg CancelButton 190,91,90,21 q2Xm~uN`) Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 $`7cs}# TextBox 220,49,40,21,.TextBox2 'default: 4 P%#WeQ+ End Dialog Pl|e?Np Dim dlg As UserDialog ;O7CahdF s^5KFK1 ok = Dialog (dlg) R7~H}>uaF }bj
dK If ok=0 Then 'cancel button was pressed Jpi\n-
d! Print "Execution cancelled." #H]cb# End A2Je*Gz End If Y@)iPK@z osKM3}Sb 'Assign accommodation and pupil diameter & use defaults if field left empty ?.E ixGzI^ If dlg.TextBox1 = "" Then _TF\y@hF*D A = 0 'Default accommodation ;dXQB>Za Else 5AmYrXZ A = CDbl(dlg.TextBox1) 7;cb^fi/ End If l=(4o4um :U^!N8i"= If dlg.TextBox2 = "" Then 4VtI8f! pupilDiam = 4 'Default pupil diameter ?6h65GO{ Else Jjt'R`t%t pupilDiam = CDbl(dlg.TextBox2) G2#={g{ End If CV/ei,=9 `
VL`8 Print " " 4F_*,_Y Print "Accommodation = " & A & " Diopters" j$Ttoo Print "Pupil Diameter = " & pupilDiam & " mm" T
KpX]H` 9uk}r; %9 ' Calculate new parameters with accommodation ]{->/.oB taq = 0.55 + 2.97 - 0.04*A 'Aqueous thickness j3j<01rq {d`e9^Z: Rant = 12.0 - 0.4*A 'Radius of anterior lens 3+6s}u) CCant = -7.518749 + 1.285720*A 'Conic constant of anterior lens
D{hsa 9 *>@s Rpost = -5.224557 + 0.2*A 'Radius of posterior lens ~*-(_<FH CCpost = -1.353971 - 0.431762*A 'Conic constant of posterior lens PoyY}Ra ]y*AA58; tlens = 3.767 + 0.04*A 'Lens thickness F
Qtlo+3 j=U
[V&T nlens = 1.42 + 0.00256*A - 0.00022*A^2 'Lens index of refraction 9f
,$JjX[ F,2)Udim 'Adjust parameters to account for accommodation 2qEm,x'S o(~QuHOp8> '************************************************************************* sflH{!;p
'Aqueous thickness (Position of Lens) Wj2s+L7, '************************************************************************* \x JGR! eID = FindFullName( "Geometry.Arizona Eye.Lens" ) BMlnzi GetCustomElement eID, entity yya"*]*S gg;&a( parID = FindFullName( "Geometry.Arizona Eye" ) y%.^|
G U=_O*n?N-d ' Delete any shift(s) in z g'G"`)~ 2 count = 0 IipG?v0z~ While GetOperationCount(eID)>count YGy.39@31 GetOperation eID, count, op *b+ef If op.Type="ShiftZ" Then /[f9Z:>V DeleteOperation eID,count ?yKW^,q+ count=count-1 Xo[={2_ End If n W2[x; count=count+1 g70B22!y Wend ve|:z H]@M00C 'Set new shift in /A3tY"Vn op.Type = "ShiftZ" jkd'2 op.val1 = taq +bwSu)k op.parent = parID Hm=!;xAFX AddOperation eID, op 0pP;[7k\ Print "Set aqueous humor thickness = " & taq-0.55 BElVkb #DMt<1#: '************************************************************************* 2BA'Zu` 'Radius and conic constant of anterior lens m'h`%0Tc '************************************************************************* T;(k eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) h+o-h4X GetConic eID, entity, curv, conic _~ m@ SI x:bJ1% SetConic eID, entity, 1/Rant, CCant R
+H0+omj Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant <ptZY.8N w4YuijhW '************************************************************************* <uUHr,# 'Radius and conic constant of posterior lens
6C6<,c '************************************************************************* > %5<fK2
eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) uW*)B_c GetConic eID, entity, curv, conic 8^26g3 7MXi_V;p< SetConic eID, entity, 1/Rpost, CCpost tuzw%=Ey Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost ,k}-I65M*t 0Da9,&D '************************************************************************* rt+%&%wt 'Lens thickness (Position of posterior lens surface) XV"8R"u%Q '************************************************************************* 5VWyc9Q k&-SB - parID = FindFullName( "Geometry.Arizona Eye.Lens" ) b,]QfC <=;#I_E#E ' Delete any z-shift(s) KiN8N=z count = 0 "F
nH>g- While GetOperationCount(eID)>count Y%AVC9( GetOperation eID, count, op ,DUD 4 [3 If op.Type="ShiftZ" Then fi*@m,- DeleteOperation eID,count F91'5D,u0 count=count-1 Wr.G9zq.+ End If eH.~c3o count=count+1 R"NR-iU Wend &s.S)'l4l IbFS8 *a\ 'Set new z-shift ZzZy2.7 op.Type = "ShiftZ" .W[ 9G\ op.val1 = tlens L4bx [ op.parent = parID ~gz_4gzb AddOperation eID, op K0hmRR= Print "Set lens thickness = " & tlens |G^w2"D_Z ?7Kl)p3 '************************************************************************* p*F.WxB)4 'Lens index of refraction xY]Y '************************************************************************* B}n
tD eID = FindMaterial( "Lens" ) 7[=MgnmuC GetModelMaterial eID, mat QDO.&G2 0Z. bd=H mat.Nd = nlens : b9X?%L~ SetModelMaterial eID, mat [I*zZ` Print "Set lens index of refraction = " & nlens 0q6$KP}q
_}4l4 '************************************************************************* q~QB?+ x& 'Pupil diameter m0*bz5 '************************************************************************* 7f!"vhCXM; eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) v<+5B5"1 Aj9<4N 'Adjust pupil diameter (trimming volume inner hole) H{Fww4pn 6Z2a5zO8 SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" NGsG4y^g?z WX@a2c.' ' Adjust pupil location to just in front of the lens S6~&g|T, parID = FindFullName( "Geometry.Arizona Eye" ) i7N|p9O. eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) g<ZB9;FX % count = 0 :xd)]Ns While GetOperationCount(eID)>count yHrYSEM GetOperation eID, count, op eiTG If op.Type="ShiftZ" Then *qM)[XO DeleteOperation eID,count oT=XCa5 count=count-1 ){~]-VK End If >x/;'Y. count=count+1 Pe-1o#7~W Wend 1?6zsA%N op.Type = "ShiftZ" 'Ipp1a
Z_M op.val1 = taq-0.01 nQy %av$ op.parent = parID o*\Fj}l- AddOperation eID, op <$ H-/~Y yL ?dC"c Print "Set pupil diameter = " & pupilDiam %3ieR}:/e& >P-{2
a,4 'Update AZ Eye subassembly Description 2<"kfan eID = FindFullName( "Geometry.Arizona Eye" ) jv<C#0E^ GetEntity eID, entity 6;JlA}) entity.Description = "Accommodation = " & A & "D" aaa6R|>0 SetEntity eID, entity _VvXE572 ,\2w+L5TD Update ~Vh< mt Print "DONE!" *Fb|iR ;:)1:Dy5 End Sub B <et&r; Y*}xD;c
k 如果屈光度是4,光瞳直径是4,则会输出如下数据: [\41 P&3Z,f0 Accommodation = 4 Diopters Hu4\4x$? Pupil Diameter = 4 mm a,>`ab%> Set aqueous humor thickness = 2.81 ;|a,1#x Set anterior lens radius = 10.4 and conic constant = -2.375869 ;s$bVGHr Set posterior lens radius = -4.424557 and conic constant = -3.081019 Imv]V6"D= Set lens thickness = 3.927 oM<Y o%n Set lens index of refraction = 1.42672 ^nPk;%`0 Set pupil diameter = 4 f_{OU
E DONE! *_Sx^`"X`l
|