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2022-02-25 09:52 |
Arizona眼睛模型
简介 h%'4V<V |<nS<x 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。 mEi+Tj zp jIY
模型 566vjE v=!Ap ; 2L 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。 "E`;8SZa Table 1. AZ眼睛模型的定义 [attachment=111140] kO3{2$S6 rGb7p`J 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. |Z%I3-z_DS Hg8n`a;R 光源 [NQ\(VQ1c (!FUu 多个光源定义来分析该模型的不同特性。图1显示了所以的光源和提示信息告诉您他们可以用来做什么。 X r7pFw Q y(Gy'q~ [attachment=111141] 图1. 光源和提示信息使用 v(ABZNIn R#j-Z#/" 除了“Letter F”之外的所有光源的光线位置设定在了孔径光阑位置处,并增加了pre-propagation distance= -8。尽管光线在光瞳处创建,规定的传输方向相对于光线位置在pre-propagation distance之后。这意味着光束沿着Z轴在眼睛的前面以平行光入射,而不是在光瞳处入射。 a*4"j2j v ,(aOTFQS 在往下看是内置的脚本用来修改屈光度,使其为4(250mm),光源“Letter F”在视网膜处生成一个字母为F的图像。绿色的光线聚焦的非常好而红色和蓝色光线有一点的模糊。使用Positions Spot Diagram分析工具来观察最为合适。 t;BvKH77 [attachment=111142] 图2. 字母F光源的设定方法光 q^{Z"ifL u{%gB&nC [attachment=111143] 图3. 字母F在视网膜上位置点列图 [hy:BV6H+ nya-Io. 视网膜的散射 HN'r
ZAZ( J?/.|Y]e 在散射文件中,有一个名为“Retina surface”的72%的反射型朗伯散射,它为视网膜的散射提供了一个粗略的近似。为了模拟来自视网膜的散射,改变自定义元件“Eye ball” 下的视网膜的表面从“halt all” 到”Allow All”。并使几何中“plane”可追迹。 -[-LR }u 1rhsmcE [attachment=111144] 图4. 视网膜朗伯散射设定 ml7nt0{ !]bXHT&!R 注意在视网膜的表面有散射重点采样规格定义,在“Scatter”标签的底部可获取该信息。“toward pupil”指定散射光朝向光瞳,半角度10度。 e&&;"^@- uQy5t:! [attachment=111145] 图5. 视网膜重点采样规格设定 >FtW~J"X ~50b$];y 脚本 At5:X*vD u3{gX{so 内置脚本使用对话框显示屈光度和光瞳直径的数值设置。使用FRED Basic脚本创建和使用对话框非常容易。图6显示了如何获取用户自定义对话框,如下图所示: 1_JxDT,=> [attachment=111146] 图6. 用户对话框的创建与编辑 \Ol3kx| [attachment=111147] 图7. 用户对话框编辑器 "BB#[@ }5n((7@X 如果“OK”按钮按下,将会核对对话框下面的代码行,如果点击取消则脚本终止。然后输入的参数赋予变量,如果此处是保留为空白,则使用默认值。因此,如果没有值输入并点击“OK”按钮,则脚本是以屈光度为0,光瞳直径为4mm来运行的。 F|._'i+B! 余下的脚本计算与屈光度有关的所有参数。 ^{<x*/ nK gv=mz,z 分析 7 mulNq S312h'K
j 屈光度为4,光瞳直径为4mm,字母F点在视网膜上所成的像。 z1\G,mJK [attachment=111148] 图7. 字母F在视网膜上颜色分析 jRz2l`~7# ZdQm&? 脚本代码 m35Blg34 |xI\)VE^
- Option Explicit 'Remove this to enable non-dimensioned variables to be used. JL~QE-pvD
YxMOr\B Dim entity As T_ENTITY G?-27Jk8 Dim op As T_OPERATION ?p{xt$<p Dim mat As T_MODELMATERIAL '[shY Dim A As Double DbSl}N ; Dim pupilDiam As Double gi`K^L=C Dim eID As Long '"}|'J Dim parID As Long 66\0JsT?3 Dim count As Integer f~Dl;f~H_; Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double 7^k`:Z Dim tlens As Double, nlens As Double myH:bc>6 Dim curv As Double, conic As Double '<
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j Dim ok As Long oRM EC7!A0 m:TS
.@p Sub Main N"|^AF {]ZZ] '用户输入对话框 (_ov_3 Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 6y)xMX TextBox 220,21,40,21,.TextBox1 'default: 0 bAeN>~WvY Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 8F0+\40 OKButton 40,91,90,21 TX{DZ# CancelButton 190,91,90,21 u(JC 4w' Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 VVuL+i TextBox 220,49,40,21,.TextBox2 'default: 4 jIMaPT End Dialog zypZ3g{vz Dim dlg As UserDialog <[xxCW(2 uR"srn;^ ok = Dialog (dlg) _<5 o1 (]0$^!YK If ok=0 Then 'cancel button was pressed XgKtg-, Print "Execution cancelled." 5VWXUNe@_q End TyMRm End If daBu<0\ "}DuAs 'Assign accommodation and pupil diameter & use defaults if field left empty oaI7j=Gp If dlg.TextBox1 = "" Then _1*EMq6 A = 0 'Default accommodation %"
$.2O@ Else `"[VkQFB/ A = CDbl(dlg.TextBox1) +-,Q>` End If 'j$iS W& 'DF3|A], If dlg.TextBox2 = "" Then u*[,W-R& pupilDiam = 4 'Default pupil diameter wd*i~A3+? Else T4T_32`XR pupilDiam = CDbl(dlg.TextBox2) ?)Lktn9% End If 4UoUuKzt v:CYf_ Print " " /-4i"| Print "Accommodation = " & A & " Diopters" wpY%"x#-+= Print "Pupil Diameter = " & pupilDiam & " mm" 5d|*E_yu {a_=4a ' Calculate new parameters with accommodation mT@UQCG taq = 0.55 + 2.97 - 0.04*A 'Aqueous thickness qsFA~{o. {i^ ?XdM Rant = 12.0 - 0.4*A 'Radius of anterior lens t=S94^g CCant = -7.518749 + 1.285720*A 'Conic constant of anterior lens ".v9#| x{ ~-YzWho Rpost = -5.224557 + 0.2*A 'Radius of posterior lens qYIBP?`g CCpost = -1.353971 - 0.431762*A 'Conic constant of posterior lens VYf$0oo\4 \WouTn tlens = 3.767 + 0.04*A 'Lens thickness j]J2,J X =S;8=N nlens = 1.42 + 0.00256*A - 0.00022*A^2 'Lens index of refraction fJOU1% 9{ i6g+ 'Adjust parameters to account for accommodation \ ;Hj,z\ a%ec: % '************************************************************************* M6AQ8~z 'Aqueous thickness (Position of Lens) *~ 4uF '************************************************************************* abD55YJY eID = FindFullName( "Geometry.Arizona Eye.Lens" ) "rc}mq GetCustomElement eID, entity Pc? d@tm xQ1&j,R] parID = FindFullName( "Geometry.Arizona Eye" ) RNoS7[& -sO EL{ ' Delete any shift(s) in z DXKk1u?Tq count = 0 ]ZO^@sH While GetOperationCount(eID)>count B_`A[0H GetOperation eID, count, op @[zPN[z. If op.Type="ShiftZ" Then lqqY5l6j DeleteOperation eID,count QEUg=*3W= count=count-1 ('
`) m End If M0c"wi@S_ count=count+1 XPUH\I= Wend 8 gOK?>'9 bvEk.~tC' 'Set new shift in kf>'AbN op.Type = "ShiftZ" ]t0?,q.$7 op.val1 = taq D6bCC;
h= op.parent = parID sF_.9G)S0 AddOperation eID, op ,PRM(n - Print "Set aqueous humor thickness = " & taq-0.55 ^fnRzX ~DqNA%Mb '************************************************************************* X~GZI*P 'Radius and conic constant of anterior lens yKZ~ ^ '************************************************************************* F1Egcx/$V eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) j(nPWEyJM GetConic eID, entity, curv, conic 'r1&zw( Vl^jTX5N SetConic eID, entity, 1/Rant, CCant 8Mws?]\/q Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant !6<2JNf o>U%3-+T^J '************************************************************************* Z`b,0[rG[ 'Radius and conic constant of posterior lens X:8=jHkz '************************************************************************* An]*J|nFIY eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) XFK$p^qu GetConic eID, entity, curv, conic \FVR'A1 Dvd.Q/f SetConic eID, entity, 1/Rpost, CCpost RG*Nw6A Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost cY\-e?`=4 ( Y/
DMQ '************************************************************************* CoJaVLl 'Lens thickness (Position of posterior lens surface) ~Gwn||g78 '************************************************************************* j nI)n* %*}JDx#@ parID = FindFullName( "Geometry.Arizona Eye.Lens" ) J|6aa A.WJ#1i}E ' Delete any z-shift(s) 9Eg'=YJ count = 0 8VMq>- While GetOperationCount(eID)>count y"@~5e477$ GetOperation eID, count, op Q.\+
XR_| If op.Type="ShiftZ" Then ;C{2*0"H| DeleteOperation eID,count <YJU?G:@ count=count-1 ) 3YE$, End If hC6$>tl count=count+1 C8&)-v| Wend +hXph b.Y[:R_9& 'Set new z-shift o6vm(I% op.Type = "ShiftZ" l[\[)X3$ op.val1 = tlens uu#ALB
Jm op.parent = parID i"w$D{N AddOperation eID, op m?<C\&)6x Print "Set lens thickness = " & tlens w:N\]=Vh % j^= '************************************************************************* @*%.V. 'Lens index of refraction f0wQn09 '************************************************************************* TC R( eID = FindMaterial( "Lens" ) ;Rwr5 GetModelMaterial eID, mat gvy%`SSW O^:Rm=,$ mat.Nd = nlens H,H'bd/ SetModelMaterial eID, mat ^lf;Lc Print "Set lens index of refraction = " & nlens @9vz%1B<l kk!}mbA_} '************************************************************************* xTAC&OCk^[ 'Pupil diameter {Ja#pt '************************************************************************* Z#4? /' eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) p(Qm\g< )*s.AFu]7x 'Adjust pupil diameter (trimming volume inner hole) W*U\79H lZ_i~;u4@v SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" G3?8GTH ?J<4IvL/ ' Adjust pupil location to just in front of the lens YToRG7X# parID = FindFullName( "Geometry.Arizona Eye" ) y!aq}YS eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) uOW9FAW count = 0 39m# While GetOperationCount(eID)>count xQJdt$]U@ GetOperation eID, count, op z@iY(;Qo If op.Type="ShiftZ" Then {W0]0_mI( DeleteOperation eID,count Uyi_B.:` count=count-1 T+2?u.{I End If *;o=hM)Tp count=count+1 )cOm\^,
Wend :&TOQ<vM op.Type = "ShiftZ" Sf*VkH op.val1 = taq-0.01 @~a52'\ op.parent = parID `^w5/v# AddOperation eID, op g~Q#U;] Xb;CY9& Print "Set pupil diameter = " & pupilDiam TH6g:YP`7 t3bDi/m 'Update AZ Eye subassembly Description ^(&:=r.PC eID = FindFullName( "Geometry.Arizona Eye" ) Qiw Zk<rb GetEntity eID, entity 0 ]NsT0M entity.Description = "Accommodation = " & A & "D" 0n3O;=[aV SetEntity eID, entity $9ON3> *M KVm)Iv Update x$M[/ID0 Print "DONE!" IlS{>6 B VPf8!- End Sub TWxMexiW Wxp^*._q3I 如果屈光度是4,光瞳直径是4,则会输出如下数据: <cWo]T`X! >#>YoA@S Accommodation = 4 Diopters >xH3*0Lp Pupil Diameter = 4 mm 9prG@ Set aqueous humor thickness = 2.81 KE(kR>OB] Set anterior lens radius = 10.4 and conic constant = -2.375869 $'[(
DwLS Set posterior lens radius = -4.424557 and conic constant = -3.081019 uYO?Rb&} Set lens thickness = 3.927 a2YdkdjT Set lens index of refraction = 1.42672 Z/ThYbk Set pupil diameter = 4 ew"[]eZ:ut DONE!
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