-
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 ROTKK8:+: g0B-<>E 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。 cRKLyb .^A4w;jPU 模型 &V
axv$v} vWmt<E|e 模型的定义如表1种所示,由半径、圆锥常数、折射率、阿贝数、到下一面的距离等一系列表面组成。一些参数由屈光度(A)来决定。 Q3i\`-kbb JG^GEJ Table 1. AZ眼睛模型的定义 Yz2N(g[ 在FRED中使用0屈光度来创建的,光瞳加在了透镜的前面。材料是创建一个新的材料并选择类型“Model Material”,输入的参数是nd和vd. a :*N0 ih)\P0wed 光源 =,it`8; r
ts2Jk7f 多个光源定义来分析该模型的不同特性。图1显示了所以的光源和提示信息告诉您他们可以用来做什么。 x$jLB&+ICz DW,ERQ^ F\&wFA'J 图1. 光源和提示信息使用 z4D)Xy"/ 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。 zfDfy!\2_ u `w w 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。 i;~.kgtq4 ~1TT ?H 图2. 字母F光源的设定方法光 T0fm6
J 5xKod0bA 图3. 字母F在视网膜上位置点列图 ^vh!1"T 视网膜的散射 xr.;B`T0\' 9E5*%Hu_ 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。 <z60EvHg 3BK
8{/ m==DBh 图4. 视网膜朗伯散射设定 JO]?u(m01 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。 _t]Q*i0p _T.`+0UV *eXs7 "H 图5. 视网膜重点采样规格设定 Edc3YSg%; 脚本 3s]o~I 2x }Uj-R3]}K 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: DJdhOLx ,e 7
~G 图6. 用户对话框的创建与编辑 EpACd8Fb 图7. 用户对话框编辑器 =_E$* } 如果“OK”按钮按下,将会核对对话框下面的代码行,如果点击取消则脚本终止。然后输入的参数赋予变量,如果此处是保留为空白,则使用默认值。因此,如果没有值输入并点击“OK”按钮,则脚本是以屈光度为0,光瞳直径为4mm来运行的。 0 7qjWo/t 余下的脚本计算与屈光度有关的所有参数。 9`qw,X&AK_ BJHWx,v 分析 GZ5 DI+3 )X *_oH= 屈光度为4,光瞳直径为4mm,字母F点在视网膜上所成的像。 (oCpQDab@ ,*V% 图7. 字母F在视网膜上颜色分析 rUV'DC?eE 脚本代码 I^LU*A= SsMs#C8u% Option Explicit 'Remove this to enable non-dimensioned variables to be used. 6 Yva4Lv iX2exJto Dim entity As T_ENTITY e
GAto Dim op As T_OPERATION ?Nt m5(R Dim mat As T_MODELMATERIAL OP(om$xm Dim A As Double ;x_T*} CH Dim pupilDiam As Double ~|~ 2B$JeV Dim eID As Long u9q#L.Ij Dim parID As Long :zIB3nT^ Dim count As Integer ]GHw~s? Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double DcRoW Dim tlens As Double, nlens As Double oKkDG|IE Dim curv As Double, conic As Double ~.e~YI80 Dim ok As Long \qW^AD(it< yHf^6|$8 Sub Main S_AN.8T u1'l4VgT '用户输入对话框 NP\/9
8|1 Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 IWddJb~hu TextBox 220,21,40,21,.TextBox1 'default: 0 66WJ=?JV Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 _Nz?fJ:$@ OKButton 40,91,90,21 btC<>(kl& CancelButton 190,91,90,21 A]'XC"lS Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 ?`
ebi|6 TextBox 220,49,40,21,.TextBox2 'default: 4 [p0_I7 End Dialog E_D@7a Dim dlg As UserDialog xOxyz6B\ m=iKu(2xRq ok = Dialog (dlg) *g'%5i1ed ki`ur%h If ok=0 Then 'cancel button was pressed <gvgr4@^yR Print "Execution cancelled." CC`#2j End {9F}2
SJ End If ucLh|}jJ5 p)Ht =~ 'Assign accommodation and pupil diameter & use defaults if field left empty F CfU=4O If dlg.TextBox1 = "" Then L?(1
[jB4G A = 0 'Default accommodation }p9#Bzc Else 5C-n"8&C& A = CDbl(dlg.TextBox1) xJ\sm8 End If 7S_"h*Ud 2mthUq9b* If dlg.TextBox2 = "" Then ?[5_/0L,= pupilDiam = 4 'Default pupil diameter YpSK|( Else v~!_DD
au pupilDiam = CDbl(dlg.TextBox2) 8Sf}z@~] End If ,I f9w$(z \S?;5LacZ Print " " NU7k2`bqAk Print "Accommodation = " & A & " Diopters" Co<F<eXe Print "Pupil Diameter = " & pupilDiam & " mm"
]>(pQD NQbgk+&wD ' Calculate new parameters with accommodation UPuG&A#VV taq = 0.55 + 2.97 - 0.04*A 'Aqueous thickness FePWr7Ze )4w3$Q Rant = 12.0 - 0.4*A 'Radius of anterior lens :?3y)*J! CCant = -7.518749 + 1.285720*A 'Conic constant of anterior lens >6zWOYd }f] ~{^ Rpost = -5.224557 + 0.2*A 'Radius of posterior lens S }G3h a CCpost = -1.353971 - 0.431762*A 'Conic constant of posterior lens b:*(
f#"q ot^$/(W tlens = 3.767 + 0.04*A 'Lens thickness M1Th~W9l h4>q~&Pd nlens = 1.42 + 0.00256*A - 0.00022*A^2 'Lens index of refraction bXWodOSN v`"BXSmp{ 'Adjust parameters to account for accommodation rY=dNK]d c=:A/z{ '************************************************************************* s(Fxi|v; 'Aqueous thickness (Position of Lens) _~b]/]|z#N '************************************************************************* Ymcc|u6 $" eID = FindFullName( "Geometry.Arizona Eye.Lens" ) m&6I@S2 GetCustomElement eID, entity +oa>k
0 }~NWOJ3; parID = FindFullName( "Geometry.Arizona Eye" ) RjHKFB2 z
2Ao6*% ' Delete any shift(s) in z % ELf7~ count = 0 8&y3oxA, While GetOperationCount(eID)>count >56;M7b(K GetOperation eID, count, op vo'{phtF)M If op.Type="ShiftZ" Then u6p
nO DeleteOperation eID,count {F$MZ2 E count=count-1 \8 -PCD End If R%%h=] count=count+1 l$!g#?w Wend wArtg'=X BxXP]od 'Set new shift in 8IihG
\ op.Type = "ShiftZ" 0o&c8?@j op.val1 = taq eRwm>l"fVV op.parent = parID 7`t[|o AddOperation eID, op !pe!Z-, Print "Set aqueous humor thickness = " & taq-0.55 )@.6u9 \ |^kfa_d '************************************************************************* #-FfyxQ8ai 'Radius and conic constant of anterior lens vEb_z[gd '************************************************************************* 0%hOB: eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) ,W&::/2<7 GetConic eID, entity, curv, conic \bWo"Yo ?Kf?Z`9 *Y SetConic eID, entity, 1/Rant, CCant hQDZ%> Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant P<gr=& ejPK-jxCa/ '************************************************************************* ]^@!ID$c 'Radius and conic constant of posterior lens ye1hcQ '************************************************************************* 7<3eB)S eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) /N(Ol WEp GetConic eID, entity, curv, conic R4g% $} >c 5V VA8 SetConic eID, entity, 1/Rpost, CCpost {nlqQ.jO Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost x 3?:"D2 D^JuL6U '************************************************************************* .6nNqGua1 'Lens thickness (Position of posterior lens surface) FrBJv< '************************************************************************* C@[f Z lCMU{) parID = FindFullName( "Geometry.Arizona Eye.Lens" ) #i~2C@] SPK%
' s ' Delete any z-shift(s) "~zQN(sR"P count = 0 1K'.QRZMb9 While GetOperationCount(eID)>count F~_)auH GetOperation eID, count, op DU%j;`3 If op.Type="ShiftZ" Then 8g CQ0w< DeleteOperation eID,count %o9;jX count=count-1 Yhkn(k2 End If ,k5b,}tN count=count+1 c|^#v8x^/ Wend $f^ \fa[ s9-aPcA 'Set new z-shift *w;=o}` op.Type = "ShiftZ" r % ]^( op.val1 = tlens 2K1odqO# op.parent = parID 3d@$iAw1< AddOperation eID, op <n:j@a\up0 Print "Set lens thickness = " & tlens L=wg"$ $5)ZaYx< '************************************************************************* e)2s2y@zi 'Lens index of refraction cp7Rpqg '************************************************************************* <_"^eF+fZ eID = FindMaterial( "Lens" ) 3bp'UEF^k GetModelMaterial eID, mat g5*Zg_G/ 7 Ed6o mat.Nd = nlens |
Djgm7$* SetModelMaterial eID, mat 9e|]H+y Print "Set lens index of refraction = " & nlens ^KK6 d H/Fq'FsQB '************************************************************************* \D37l_ 'Pupil diameter 9"YOj_z '************************************************************************* [j:]YR eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) wKq-|yf, 'h&"xXv4| 'Adjust pupil diameter (trimming volume inner hole) @Gj|X>0 3K57xJzK SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" HjO-6F#s l}$Pv?T,2 ' Adjust pupil location to just in front of the lens ag$mc8-p[ parID = FindFullName( "Geometry.Arizona Eye" ) aQK>q. t eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) z5G$' count = 0 62 biOea While GetOperationCount(eID)>count k-b0Eogp] GetOperation eID, count, op |hprk-R*OH If op.Type="ShiftZ" Then 9)a:8/Y DeleteOperation eID,count -nQ :RHnd count=count-1 rU/V~;#% End If Y!6,ty' count=count+1 9(>l trA Wend *$ihNX]YG op.Type = "ShiftZ" <XV\8Y+n op.val1 = taq-0.01 XD8MF)$9 op.parent = parID vbeYe2;( AddOperation eID, op q+/c+u?=^ xYJ|G=h&A Print "Set pupil diameter = " & pupilDiam I3A@0'Vm;L ^uu)| 'Update AZ Eye subassembly Description Z[DiLXHL eID = FindFullName( "Geometry.Arizona Eye" ) Ed%8| M3 GetEntity eID, entity g$\Z-!( entity.Description = "Accommodation = " & A & "D" 75t\= 6# SetEntity eID, entity YJlpP0;++ :n:Gr? Update (bIg6_U7\ Print "DONE!" "YUyM5X /=zzym~<> End Sub 4wZ{Z
2w D|u! KH 如果屈光度是4,光瞳直径是4,则会输出如下数据: \k{UqU+s s:j"8ZH Accommodation = 4 Diopters `JGV3nN Pupil Diameter = 4 mm 38wt=0br Set aqueous humor thickness = 2.81 h]rF2 B Set anterior lens radius = 10.4 and conic constant = -2.375869 )19As8rL/o Set posterior lens radius = -4.424557 and conic constant = -3.081019 cC.=,n Set lens thickness = 3.927 mr+J# Set lens index of refraction = 1.42672 K0#kW \4` Set pupil diameter = 4 2l)J,z
DONE! Cz2OGM*mz? !H`Q^Xf} /-ebx~FX& QQ:2987619807 ?qeBgkL(B^
|