[技术]RPC Photonics扩散片BSDF [复制链接]

摘要： &hL2xx=  
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RPC Photonics公司有高品质的的工程漫射体BSDF测试数据，但它对于FRED帮助甚少，下面这个步骤描述了如何利用FRED脚本转换RPC Photonics提供的TXT文件，并将数据直接应用到FRED的Tabulated scatter 散射模型。 LdNpb;*  
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背景： m||9,z-  
Thorlabs和RPC Photonics联手共同推出的新型漫射体及光束整形技术，可以解决其他技术的不足，大大改善了诸如光刻系统、有效固态照明，显示，背光，显示亮度增强和投影屏等大多数应用的性能。这项我们称之为工程漫射体（Engineered DiffusersTM）的新概念，与其他技术有许多不同。与诸如磨砂玻璃、乳色玻璃和全息元件等随机漫射体截然不同，工程漫射体要求对于每个散射中心，通常为微透镜单元，都进行控制。例如全息漫射体可以视为一组随机排列的透镜，但是通过全息曝光形成的类透镜效果只能通过静态方式进行控制：而无法单独操控每个微透镜单元，这也帮助解释了全息漫射体无法控制光的分布和轮廓。另一方面，在工程漫射体中，每个微透镜单元形成漫射体，由其凹形纵断面和在阵列中的位置所确定。同时，为了确保漫射体不受输入光束变化的影响，并且不产生衍射效果，微透镜单元的分布是随机的，根据产生相应的光束形状函数所选取的概率分布函数来确定。因此，工程漫射体同时保留了随机与确定性漫射体的优点，从而实现高性能的光束整形功能。 'yA/sZ  
FRED是美国Photon Engineering 公司开发的光学工程仿真软件，其在杂散光分析中独特的算法、高效的准确性，使其与其它同类产品相比更具优势。本案例我们重点讲述如何由RPC Photonics的BSDF数据转为FRED可识别的散射数据。 OUGkam0UK  
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步骤 >D~8iuy]8.  
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1、 在http://www.rpcphotonics.com/bsdf-data-optical-diffusers/下载并解压BSDF数据到某一文件夹下，选择“Raw data”文件。 $2i@@#g8  
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2、 将     http://fred-kb.photonengr.com/wp-content/uploads/sites/2/2015/06/constructRpcScatterFile.frs脚本文件放在步骤1中的文件下。（脚本代码放在了本文的最后） e`7>QS;.  
3、 打开FRED并运行脚本文件，会输出如下“<SAMPLE>_FRED.txt”格式，<SAMPLE>即为RPC Photonics散射片数据集 LJ@r+|>  
例如下所示： X;)/<:mX  
Sample name:  EDF-C1-56 F?H=2mzKbz  
Merging data from file EDF-C1-56 0-0.txt 2@z.ory.  
Finished merging RPC data for sample EDF-C1-56 }}~a4p>%  
FRED formatted data file:  D:\FRED\散射片数据\EDF-C1-56_FRED.txt CqZHs 9+e&  
4、 生成了FRED可识别的文件后，将散射模型导入到FRED里面 +5Dc5Bl  
a. 创建一个新的散射库 [v*q%Mi_  
b. 散射模型命名 C3f\E: D)  
c. 改变散射模型为“Tabulated BSDF”. EleJ$ `/  
d. 在File框出右键选择“Replace With Data From a File”, 选择步骤三生成的数据文件（如EDF-C1-56_FRED.txt ） Dg0rVV6c  
e. 切换为“Varies w/angle” 选项（假定所有的RPC Photonics datasets 数据有多个测试角度。 W  
f. 在底部的对话框中，选择透射散射、反射停并且你需要终止入射光线， 'OP0#`6`  
g. 点击OK vF'>?O?  
5、 数据输入后，可点击“Plot”按钮验证BSDF模型及总的散射值 oxL<\4)WJ  

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脚本代码： .7b%7dQ<\  
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'#Language "WWB-COM" Ma$~B0!;s  
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Option Explicit eh]syeKBj  
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Sub Main 2YW;=n  
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    'Cleanup ,~ZD"'*n6g  
    ClearOutputWindow() D^.  c:  
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    Print "Merging RPC Photonics BSDF Data Files" Jx}-Y* o  
    SetTextColor(255,0,0) gSw<C+  
    Print "Note: Script should be located in the same folder as the BSDF TXT files." {R@V  
    Print "Note: Do not run this script multiple times without deleting the output file between executions." m26YAcip}  
    SetTextColor(0,0,0) nC%qdzT  
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    'Current directory of this script (should be the same as the text files being merged) U887@-!3  
    Dim cDir As String +M_
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    cDir = MacroDir$ & "\" S-gO  
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    'Array which will be populated with the list of files to be merged <Ohi+a%6  
    Dim fList() As String, curFile As String 0!lWxS0#=  
    GetFileList( cDir, fList ) *DfOm`m  
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    Print "" 3Zd,"/RH  
    Print "Files found for merging:" ;e5PoLc  
    For Each curFile In fList z rSPa\M  
        Print Chr(9) & curFile YT(Eh3ID  
    Next {b4`\I@<  
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    'Split the first text file name found to get the sample name.  First file should be 0-0 measurement. ^w~B]*A:"  
    Dim nameArray() As String, sampName As String [yQ%g;m  
    nameArray = Split(fList(0)," 0-0.txt") L98T!5)  
    sampName  = nameArray(0)
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    Print "" N\|z{vn  
    Print "Sample name: " & Chr(9) & sampName G(#t,}S}@  
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    'Open an output file and write the FRED header data !vRZh('R  
    Dim outFile As String M;ADL|  
    outFile = cDir & sampName & "_FRED.txt" eU%49 A  
    Open outFile For Output As #1 -2J37   
    Print #1, "type bsdf_data" 04;s@\yX4  
    Print #1, "format angles=deg bsdf=value scale=1" -NN=(p!<  
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    'Loop the file list, skip the two header lines and write the remaining data to file ([<HFc`  
    Dim lineArray() As String, curLine As Long ;]=w6'dP!  
    For Each curFile In fList T pF[-fO  
        Print "Merging data from file " & curFile -W('^v_*  
        ReadFile( cDir & curFile, lineArray ) F.$z7ee@  
        For curLine = 2 To UBound(lineArray) .aY$-Y<  
            Print #1, lineArray(curLine) KU` *LB:  
        Next ?=&S?p)-<  
    Next ur'<8pDb$  
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    'Close the output file b}0h()v  
    Close #1 4y7_P0}:B  
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    Print "Finished merging RPC data for sample " & sampName UcQ]n0J=Z  
    Print "FRED formatted data file: " & Chr(9) & outFile A<)n H=G&  
End Sub EyPJ Jc8  
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'Utility function to read the contents of a file into an array of strings. 7<WS@-2I#  
Function ReadFile(ByVal fileName As String, _ 70R6:  
                  ByRef lineArray() As String) As Long ?cRF;!o"  
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    ReadFile = -1 ye$_=KARP  
    Dim oFSO As Object BM /FOY;  
    Set oFSO = CreateObject("Scripting.FileSystemObject") fS4W*P[B3  
    Erase lineArray \~%+)a%%  
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    Dim fid As Long *%KIq/V  
    If oFSO.fileexists( fileName ) Then 63u%=-T%a  
        fid = FreeFile() Q+ 
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        Open fileName For Input As fid v~
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        lineArray = Split(Input(LOF(fid), fid), vbCrLf) JnBc@qnP6  
        Close fid .i4aM;Qy  
    End If `~u=[}w  
    Set oFSO = Nothing }bS1M  
    Return UBound( lineArray ) I&La0g_E  
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End Function o1(;"5MM  
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Sub GetFileList( ByVal in_dir As String, _ uKk#V6
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                 ByRef in_flist() As String ) 'M"z3j]m-,  
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    'Redimension the file list array [6mK<A,/  
    Erase in_flist 0@"'SKq  
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    'Tracks how many files are found J2VPOn  
    Dim fCount As Long ?Xypn#OPt  
    fCount = 0 1 gjaTPwY  
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    'Recurse directory and search for text files C
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    Dim f As String jJiuq#;T3  
    f = Dir$(in_dir & "*.txt") %;:![?M  
    While f <> "" 7w)8s  
        ReDim Preserve in_flist(fCount) >]~581fYf  
        in_flist(fCount) = f Pt5wm\  
        fCount += 1 a^J(TW/  
        f = Dir$() l.pxDMY  
    Wend vm+3!s:u  
    ReDim Preserve in_flist(fCount-1) hTLf$_|P  
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End Sub j? BL8E'