Arizona眼睛模型

N5#qox$D   人眼光学模型可用来设计眼科用设备，光学系统注定了要与人眼一起使用。本文演示了这样一个模型：Arizona眼睛模型，在Jim Schwiegerling教授的书中有详细描述：《Field Guide to Visual and Ophthalmic Optics》。AZ眼睛模型达到了基于平均临床数据所决定的轴上和轴外像差等级。FRED文件包含了此眼睛模型及几个用来分析它的光源，并包括一个基于想要的屈光度来调整模型的内嵌脚本。 xY(+[T!OF   ,w,>pO'[   模型 .FK[Y?ci#   A3*ti!X<6   模型的定义如表1种所示，由半径、圆锥常数、折射率、阿贝数、到下一面的距离等一系列表面组成。一些参数由屈光度（A）来决定。 \xkLI:*\   Table 1. AZ眼睛模型的定义 *#;8mM   Z2)f$ c   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. TC?kuQI   yc|C} oQF   光源 l " pCxA   9vWKyzMi   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。 !;{@O`j?b   yA?>v'K   图1. 光源和提示信息使用 g_G?gO   v:B_%-GfOA   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。 bYQ h{q   Bwjd/id q   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。 au9r)]p-   图2. 字母F光源的设定方法光 jFM8dl n   nQdNXv<(   图3. 字母F在视网膜上位置点列图 ^c83_93)R   `Gx"3ZUn   视网膜的散射 $^ (q0zR~l   2`+ ?s   在散射文件中，有一个名为“Retina surface”的72%的反射型朗伯散射，它为视网膜的散射提供了一个粗略的近似。为了模拟来自视网膜的散射，改变自定义元件“Eye ball” 下的视网膜的表面从“halt all” 到”Allow All”。并使几何中“plane”可追迹。 >9a%"<(2#   H$KE*Wwq   图4. 视网膜朗伯散射设定 }oYR.UH   s=(~/p#M   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。 OHssUt   Xx[ LK   图5. 视网膜重点采样规格设定 >C+0LF`U   1)/B V{n   脚本 F+*>q   %5 6pP"w   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： GsqR8n=   图6. 用户对话框的创建与编辑 jz't!wj   图7. 用户对话框编辑器 9<kKno   M$1+,[^f   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。 qnW5I_ ]   余下的脚本计算与屈光度有关的所有参数。 [@kzC/Jq3   ,a?)#X   分析 ?*u)T%S   EhEn|%S   屈光度为4，光瞳直径为4mm，字母F点在视网膜上所成的像。 tirw{[X0n   图7. 字母F在视网膜上颜色分析 WEqHL,Uh]   #I%< 1c%XA   脚本代码 (6u<w#u   G(JvAe]r   Option Explicit     'Remove this to enable non-dimensioned variables to be used. 7 tF1g=\   _S8]W !c   Dim entity As T_ENTITY reM%GU   Dim op As T_OPERATION |O\(<n S   Dim mat As T_MODELMATERIAL BT 98WR"\   Dim A As Double uQ&&?j   Dim pupilDiam As Double _E)x R   Dim eID As Long 7$x@;%xd   Dim parID As Long 5U|f"3&8   Dim count As Integer P0RMd f   Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double \>cZ=   Dim tlens As Double, nlens As Double |?s%8c'w=   Dim curv As Double, conic As Double 'gUHy1p   Dim ok As Long 3Aaj+=]W   S#jH2fRo   Sub Main }n6BI}n   Xu3^tH-b<       '用户输入对话框 qw%4j9}       Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 )7q;Fm_/           TextBox 220,21,40,21,.TextBox1 'default: 0 dulW!&*No           Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 ?P<&8eY           OKButton 40,91,90,21 8PXleAn           CancelButton 190,91,90,21 oVoTnGNM6           Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 ~#I1!y~`           TextBox 220,49,40,21,.TextBox2 'default: 4 U(W#H|       End Dialog zq4,%$y8|       Dim dlg As UserDialog 7*'_&0    3tnYK&       ok = Dialog (dlg) "uGJ\   /,Ln)?eD       If ok=0 Then    'cancel button was pressed Zdh4CNEeFP           Print "Execution cancelled." Se"\PxBR           End |t]-a%A=w       End If .Yha(5(   |YZ`CN<       'Assign accommodation and pupil diameter & use defaults if field left empty x18ei@c       If dlg.TextBox1 = "" Then lqX]'gu]\           A = 0           'Default accommodation 7X|&:V.s|       Else %|SbZ)gcQ           A = CDbl(dlg.TextBox1) g/`i:=       End If c1|o^eZ   wjS3ItB       If dlg.TextBox2 = "" Then KT?vs5jg$&           pupilDiam = 4   'Default pupil diameter zG [-n.       Else C9gF2ii|?           pupilDiam = CDbl(dlg.TextBox2)  LE1&atq       End If z+wV(i97   T%P0M*       Print " " Vy}:Q[       Print "Accommodation = " & A & " Diopters" 2 Q9s?C       Print "Pupil Diameter = " & pupilDiam & " mm" _<t3~{qUT   eDaVoc3       ' Calculate new parameters with accommodation v{JCEb&wN       taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness _ esFx   /DbwqBx       Rant = 12.0 - 0.4*A                     'Radius of anterior lens >kC@7h5)       CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens EVb'x Zr   pNQd\nY|0       Rpost = -5.224557 + 0.2*A               'Radius of posterior lens gkBat (Uc       CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens AN T^&NjJ7   NNe'5q9       tlens = 3.767 + 0.04*A                  'Lens thickness H7l[5ib   =i:?4pIZ       nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction YnJ=&21   !vImmhI!I       'Adjust parameters to account for accommodation W!IK>IW"   'J!P:.=a>       '************************************************************************* v`w Pdb       'Aqueous thickness (Position of Lens) O~qB       '************************************************************************* zKT \i       eID = FindFullName( "Geometry.Arizona Eye.Lens" ) 3c9v~5og4       GetCustomElement eID, entity s?0r\cc|:   {_k 6t       parID = FindFullName( "Geometry.Arizona Eye" ) \BJnJk!%   vtL)       ' Delete any shift(s) in z $Q47>/CUc^       count = 0 3*8#cSQ/6o       While GetOperationCount(eID)>count ^GRd;v=-@           GetOperation eID, count, op DCwldkdJN           If op.Type="ShiftZ" Then W9eR3q               DeleteOperation eID,count Q|pz].0               count=count-1 (%I`EAR           End If g1&GX(4[           count=count+1 \;P Bx &       Wend iT.hXzPzr*   ENqJ9%sk7       'Set new shift in 2H]&3kM3X       op.Type = "ShiftZ" Zqx5I~       op.val1 = taq zEks4yd       op.parent = parID `0.5aa       AddOperation eID, op A;2?!i#f       Print "Set aqueous humor thickness = " & taq-0.55 }]g>PY   Kx<bVK4"       '************************************************************************* \UNw43EL       'Radius and conic constant of anterior lens ->93.sge       '************************************************************************* *a$z!Ma3h       eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) 2RM0ca_F       GetConic eID, entity, curv, conic @x{;a9y   hV=)T^Q       SetConic eID, entity, 1/Rant, CCant 66z1_lA       Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant p&ZD1qa   "G4{;!0C       '************************************************************************* #>>-:?X       'Radius and conic constant of posterior lens a nIdCOh       '************************************************************************* C:P,q6       eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) 1lMU('r%       GetConic eID, entity, curv, conic /B1NcRS   M4')gG;       SetConic eID, entity, 1/Rpost, CCpost Bd\p!f<       Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost sq :ff   t,=khZ       '************************************************************************* zeR!Y yt!       'Lens thickness (Position of posterior lens surface) gy*N)iv%       '************************************************************************* 81aY*\   k6*2= xK~       parID = FindFullName( "Geometry.Arizona Eye.Lens" ) AZtZa'hbkQ   NCl={O9<j       ' Delete any z-shift(s) T.&^1qWWA       count = 0 v}[7)oj|       While GetOperationCount(eID)>count f+gyJ#R`           GetOperation eID, count, op jQ7RH/?_           If op.Type="ShiftZ" Then .\1XR               DeleteOperation eID,count WU}JArX9               count=count-1 - d>)           End If Ym!Ia&n           count=count+1 lfWxdi       Wend ^#"!uCq]gM   ~W`upx)j       'Set new z-shift *4+;Ey       op.Type = "ShiftZ" 2&5"m;<       op.val1 = tlens K4l, YR;r       op.parent = parID )!M:=}."       AddOperation eID, op ]M= 3Sn8}       Print "Set lens thickness = " & tlens vp-)$f&   -bKli<C       '************************************************************************* FtE%<QHt       'Lens index of refraction J^1w& 40       '************************************************************************* {]|};E[}m       eID = FindMaterial( "Lens" ) oIbd+6>f       GetModelMaterial eID, mat 3QGg;    I_eYTy-a`1       mat.Nd = nlens (wvDiW5       SetModelMaterial eID, mat #9p{Y}2#       Print "Set lens index of refraction = " & nlens %.[GR   !XgkK k       '************************************************************************* 9I9J}&4       'Pupil diameter Po=)jkW       '************************************************************************* I[&z#foN=w       eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) Q{mls   qTiX;e\W       'Adjust pupil diameter (trimming volume inner hole) U2+CL)al^   W^al`lg+y       SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" <W\~A$   d<: VoQM6M       ' Adjust pupil location to just in front of the lens UAH} ])U       parID = FindFullName( "Geometry.Arizona Eye" ) 7kG>s9O       eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) }^P(p?~       count = 0 G4AX8@;U       While GetOperationCount(eID)>count Gl}=Q7           GetOperation eID, count, op RQ9T<t42           If op.Type="ShiftZ" Then J%D'Xlb               DeleteOperation eID,count O,:ent|               count=count-1 bg[q8IBCd           End If tse(iX/D           count=count+1 ugucq},[       Wend pD.7ib^       op.Type = "ShiftZ" RR^I*kRH       op.val1 = taq-0.01 E}\^GNT       op.parent = parID 9 `J`(       AddOperation eID, op fm:/}7s   +<@7x16       Print "Set pupil diameter = " & pupilDiam 0XL x@FYn   I=Ws /+       'Update AZ Eye subassembly Description )#i]exZ       eID = FindFullName( "Geometry.Arizona Eye" ) xzIs,i}U       GetEntity eID, entity A3yVT8       entity.Description = "Accommodation = " & A & "D" yIqsZJj       SetEntity eID, entity Z4bN|\I    1OE^pxfi>       Update kB"Sh_:m       Print "DONE!" :3{@LOil^        ~F>oNbJIv   End Sub B >#zrCD   fy9{W@E3p   如果屈光度是4，光瞳直径是4，则会输出如下数据： #j iQa"   VLu_SXlo*   Accommodation = 4 Diopters h'w9=Pk~6y   Pupil Diameter = 4 mm Lg_y1Mu7o   Set aqueous humor thickness = 2.81 7Dom[f   Set anterior lens radius = 10.4 and conic constant = -2.375869 `H^Nc\P#   Set posterior lens radius = -4.424557 and conic constant = -3.081019 BxO2w1G   Set lens thickness = 3.927 cd*y{Wt   Set lens index of refraction = 1.42672 XC0G5rtB   Set pupil diameter = 4 -5kq9Dy\,   DONE!

dg/7?gV

6i%LM`8GEk