Arizona眼睛模型

ATjE8!gO!   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。 q^h/64F   {RI)I   模型 Ho1V)T >   9ePom'1f1   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。 >65\   Table 1. AZ眼睛模型的定义 OO\$'% y`   N v6=[_D   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. 5,?^SK|'x   Q9i[?=F:z   光源 b-RuUfUn0   1p8hn!V   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。 Z1{>"o:@   I.it4~]H   图1. 光源和提示信息使用 *W2o$_Hs   9-!GYa'Z   除了“Letter F”之外的所有光源的光线位置设定在了孔径光阑位置处，并增加了pre-propagation distance= -8。尽管光线在光瞳处创建，规定的传输方向相对于光线位置在pre-propagation distance之后。这意味着光束沿着Z轴在眼睛的前面以平行光入射，而不是在光瞳处入射。 bu{dT8g'U   9I(00t_   在往下看是内置的脚本用来修改屈光度，使其为4（250mm），光源“Letter F”在视网膜处生成一个字母为F的图像。绿色的光线聚焦的非常好而红色和蓝色光线有一点的模糊。使用Positions Spot Diagram分析工具来观察最为合适。 "[0.a\ d<   图2. 字母F光源的设定方法光 gv1y%(`|n(   -_= m j   图3. 字母F在视网膜上位置点列图 Hyi'z 1   +[}<u--   视网膜的散射 e xkPu-[W   D"exI]   在散射文件中，有一个名为“Retina surface”的72%的反射型朗伯散射，它为视网膜的散射提供了一个粗略的近似。为了模拟来自视网膜的散射，改变自定义元件“Eye ball” 下的视网膜的表面从“halt all” 到”Allow All”。并使几何中“plane”可追迹。 QOY{j   EI496bsRHm   图4. 视网膜朗伯散射设定 hD{ `j   R?M>uaxn   注意在视网膜的表面有散射重点采样规格定义，在“Scatter”标签的底部可获取该信息。“toward pupil”指定散射光朝向光瞳，半角度10度。 [Y.=bfV!   [S9"' ^H   图5. 视网膜重点采样规格设定 TX;)}\   ^0-e.@   脚本 5v^tPGg4   ja6V*CWb   内置脚本使用对话框显示屈光度和光瞳直径的数值设置。使用FRED Basic脚本创建和使用对话框非常容易。图6显示了如何获取用户自定义对话框，如下图所示： 45&Rl,2   图6. 用户对话框的创建与编辑 3,n"d-   图7. 用户对话框编辑器 KDb`g}1Q   v-wZHkdd1   如果“OK”按钮按下，将会核对对话框下面的代码行，如果点击取消则脚本终止。然后输入的参数赋予变量，如果此处是保留为空白，则使用默认值。因此，如果没有值输入并点击“OK”按钮，则脚本是以屈光度为0，光瞳直径为4mm来运行的。 Z\cD98B#   余下的脚本计算与屈光度有关的所有参数。 y+KAL{AGK   .A0fI" ;Q   分析 e^;%w#tEqI   1 J}ML}h)   屈光度为4，光瞳直径为4mm，字母F点在视网膜上所成的像。 )_Z^oH ]<   图7. 字母F在视网膜上颜色分析 hzT)5'_   %m+7$iD   脚本代码 Hg$7[um   v0?SN>fZ   Option Explicit     'Remove this to enable non-dimensioned variables to be used. #\_8y`{x   EW r7eH   Dim entity As T_ENTITY >P]gjYN   Dim op As T_OPERATION 0Ua=&;/2   Dim mat As T_MODELMATERIAL q@tym5   Dim A As Double zQ#*O'-n   Dim pupilDiam As Double %0 i)l|   Dim eID As Long |(AFU3~   Dim parID As Long (][-()YV   Dim count As Integer .(3ec/i4CF   Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double X?XB!D7[   Dim tlens As Double, nlens As Double v\_\bT1   Dim curv As Double, conic As Double {e q378d   Dim ok As Long q^?a|l   g> ~+M   Sub Main r=~K#:66   ]"~ x       '用户输入对话框 jOzi89       Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 ~Z!YB,)bp           TextBox 220,21,40,21,.TextBox1 'default: 0 klH? !r&           Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 @b,6W wc           OKButton 40,91,90,21 Gp+\}<^Z           CancelButton 190,91,90,21 +k~0&lZi           Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 v1Q78P           TextBox 220,49,40,21,.TextBox2 'default: 4 b%vIaP|]B       End Dialog boHbiE       Dim dlg As UserDialog +vxOCN4}v   *C<;yPVc       ok = Dialog (dlg)  lfre-pS+   !zllvtK4       If ok=0 Then    'cancel button was pressed r7L.W            Print "Execution cancelled." /'5d0' ,M           End ;Rpib[m       End If |:.Uw\z5'   `*BV@       'Assign accommodation and pupil diameter & use defaults if field left empty R PoBF~>       If dlg.TextBox1 = "" Then t 7o4 aBl"           A = 0           'Default accommodation ,.}%\GhY       Else wc.=`Me           A = CDbl(dlg.TextBox1) x )GheM^       End If 9t6c*|60#n   |cgjn*a?M       If dlg.TextBox2 = "" Then K&Bbjb_|           pupilDiam = 4   'Default pupil diameter Y;%LwDC       Else (CY D]n           pupilDiam = CDbl(dlg.TextBox2) CtV|oeJ       End If r-TrA$k   Ff(};$/&W       Print " " MfHOn YV       Print "Accommodation = " & A & " Diopters" +L`}(yLJ)9       Print "Pupil Diameter = " & pupilDiam & " mm" {Dk!<w I)   s\pukpf@       ' Calculate new parameters with accommodation ge:a{L       taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness Tjq1[Wq   $#p5B QQ|       Rant = 12.0 - 0.4*A                     'Radius of anterior lens BAY e:0       CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens BxjSo^n   p:5NMo       Rpost = -5.224557 + 0.2*A               'Radius of posterior lens Y0T:%       CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens IZ7o6Etti   lwrh4<~\,*       tlens = 3.767 + 0.04*A                  'Lens thickness IGQBTdPUa   pGjwI3_K       nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction X%j`rQk`   7C0xKF       'Adjust parameters to account for accommodation 8FMxn{k2   *DC/O( 0       '************************************************************************* GWWg3z.o"W       'Aqueous thickness (Position of Lens) yxHo0U       '************************************************************************* >Zs!       eID = FindFullName( "Geometry.Arizona Eye.Lens" ) vI0,6fOd6       GetCustomElement eID, entity &1yJrj9y   wjwCs`       parID = FindFullName( "Geometry.Arizona Eye" ) #}+H   W"\}##       ' Delete any shift(s) in z |-b\N6 }       count = 0 boGdZ2$h4       While GetOperationCount(eID)>count GdI,&|/           GetOperation eID, count, op *X/Vt$P           If op.Type="ShiftZ" Then ;!A8A4~nu               DeleteOperation eID,count I`X!M!dB)               count=count-1 grzmW4Cw           End If bs?\ )R5/           count=count+1 rzIWQFv       Wend @jm+TW    eyJWFJh       'Set new shift in oI/_ WY[t       op.Type = "ShiftZ" 7 PMz6       op.val1 = taq Rw{' O]Q*       op.parent = parID j \jMN*dmV       AddOperation eID, op 1F,U^O       Print "Set aqueous humor thickness = " & taq-0.55 c-(RjQ~M5   :_6o|9J\t       '************************************************************************* BInSS*L       'Radius and conic constant of anterior lens J<"K`|F       '************************************************************************* * @]wT'       eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) C/Tk`C&       GetConic eID, entity, curv, conic CLzF84@W=   jmwN1Se>       SetConic eID, entity, 1/Rant, CCant SoM,o]s#y       Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant H\oxj,+N   ,HTwEq>-G       '************************************************************************* E> GmFw       'Radius and conic constant of posterior lens <Y7j'n       '************************************************************************* U1y!R<qlp       eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) t2)uJN`a$X       GetConic eID, entity, curv, conic 6Q7=6   "h_f-vP       SetConic eID, entity, 1/Rpost, CCpost ]pBEoktp       Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost 9DhM 9VU   LF!KP       '************************************************************************* ~6kF`}5       'Lens thickness (Position of posterior lens surface) e8("G[P>       '************************************************************************* fYy w2"   yKl^-%Uq<       parID = FindFullName( "Geometry.Arizona Eye.Lens" ) ,]wQ]fpt   >y#MEN>?       ' Delete any z-shift(s) r4/b~n+*       count = 0 z0/+P       While GetOperationCount(eID)>count Yc]k<tQ           GetOperation eID, count, op OP=brLGu0           If op.Type="ShiftZ" Then t;VMtIW+E               DeleteOperation eID,count )jgz(\KZ               count=count-1 -c?x5 /@3           End If  VQH48{X           count=count+1 ^g6v#]&WA       Wend b'+Wf#.]f0   K BtqtE'(L       'Set new z-shift 1/?Wa       op.Type = "ShiftZ" WLXt@dK*u       op.val1 = tlens ,dQ*0XO!       op.parent = parID e8 ]C B       AddOperation eID, op GBb8}lx       Print "Set lens thickness = " & tlens 13/,^?   C('D]u$Hdk       '************************************************************************* WuY#Kx~2       'Lens index of refraction !Z2h?..O       '************************************************************************* 5A`>3w{3n       eID = FindMaterial( "Lens" ) [>?|wQy>=       GetModelMaterial eID, mat 6O{QmB0KK   e_epuki       mat.Nd = nlens .jqil0#)Y"       SetModelMaterial eID, mat W)r|9G8T       Print "Set lens index of refraction = " & nlens A,EG0yb   }w35f G^       '************************************************************************* -{OJM|W+       'Pupil diameter i=n;rT       '************************************************************************* PU.j(0       eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) 8/R$}b><   3l~7       'Adjust pupil diameter (trimming volume inner hole) }rmr0Bh   :!Q(v( M       SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" Xk%eU>d   GOdWc9Ta!       ' Adjust pupil location to just in front of the lens -FZNk}       parID = FindFullName( "Geometry.Arizona Eye" ) h!(# /       eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) .$cX:"_Mk       count = 0 `$1A;wg<       While GetOperationCount(eID)>count G2wSd'n*y           GetOperation eID, count, op x'}zNEXI           If op.Type="ShiftZ" Then H?r~% bh               DeleteOperation eID,count vqT)=ZC1               count=count-1 <ndY6n3           End If +pq=i           count=count+1 ?H_@/?       Wend /!Ag/SmS!9       op.Type = "ShiftZ" YR\(*LJL       op.val1 = taq-0.01 8u)>o* :       op.parent = parID /V+7:WDj       AddOperation eID, op [g"nu0sOK   Dj=$Q44       Print "Set pupil diameter = " & pupilDiam "kcix!}&   u8?$W%eW       'Update AZ Eye subassembly Description ux^rF       eID = FindFullName( "Geometry.Arizona Eye" ) =jm\8sl~~       GetEntity eID, entity mvpcRe <       entity.Description = "Accommodation = " & A & "D" &k*oG:J3       SetEntity eID, entity <nk/w5nKL   :## $-K*W"       Update oc-&}R4=       Print "DONE!" :_HdOm        GE] QRKf   End Sub a6:hH@,   %8DI)n#H   如果屈光度是4，光瞳直径是4，则会输出如下数据： %=K[C   J=kf KQV   Accommodation = 4 Diopters Y#9bM$x7   Pupil Diameter = 4 mm GK6~~ga=   Set aqueous humor thickness = 2.81 AwuhFPG   Set anterior lens radius = 10.4 and conic constant = -2.375869 =`(W^&|   Set posterior lens radius = -4.424557 and conic constant = -3.081019 6j1C=O@S   Set lens thickness = 3.927 cna%;f.   Set lens index of refraction = 1.42672 \goiW;b   Set pupil diameter = 4 nZYO}bv\   DONE!

}vP (SF6

H^o_B1