[技术]RPC Photonics扩散片BSDF [复制链接]

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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。 1jmjg~W  
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背景： !{+,B5 Hc  
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。 a{L%7  
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。 JinU
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步骤 ^rB8? kt  
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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。 f$o_e90mu  
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2、 将     http://fred-kb.photonengr.com/wp-content/uploads/sites/2/2015/06/constructRpcScatterFile.frs脚本文件放在步骤1中的文件下。（脚本代码放在了本文的最后） 7m47rJyW4  
3、 打开FRED并运行脚本文件，会输出如下“<SAMPLE>_FRED.txt”格式，<SAMPLE>即为RPC Photonics散射片数据集 I }a`0Y&{  
例如下所示： pE3?"YO  
Sample name:  EDF-C1-56 3p$?,0ELH  
Merging data from file EDF-C1-56 0-0.txt ~T"Rw2vb  
Finished merging RPC data for sample EDF-C1-56 7zl5yKN  
FRED formatted data file:  D:\FRED\散射片数据\EDF-C1-56_FRED.txt ,5P0S0*{  
4、 生成了FRED可识别的文件后，将散射模型导入到FRED里面 O
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a. 创建一个新的散射库 mtpeRVcF  
b. 散射模型命名 ^L,K& Jd  
c. 改变散射模型为“Tabulated BSDF”. 8v6(qBK  
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 ） xBj9yu  
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。 dUD[e,?  
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， 4V"E8rUL(  
g. 点击OK ob!P;]T  
5、 数据输入后，可点击“Plot”按钮验证BSDF模型及总的散射值 7RQR)DG  
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脚本代码： <q)#  
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'#Language "WWB-COM" 3RUy,s  
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Option Explicit p0]=QH  
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Sub Main ;t)
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    'Cleanup k<z)WNBf  
    ClearOutputWindow() d.aS{;pse  
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    Print "Merging RPC Photonics BSDF Data Files" M+oHtX$  
    SetTextColor(255,0,0) I !- U'{  
    Print "Note: Script should be located in the same folder as the BSDF TXT files." gZV
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    Print "Note: Do not run this script multiple times without deleting the output file between executions." \a<wKTkn  
    SetTextColor(0,0,0) s$IDLs,WM  
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    'Current directory of this script (should be the same as the text files being merged) U
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    Dim cDir As String )J=!L\  
    cDir = MacroDir$ & "\" \-E^lIVF  
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    'Array which will be populated with the list of files to be merged J@`1TU  
    Dim fList() As String, curFile As String 7o\@>rNWP  
    GetFileList( cDir, fList ) xexaQuK  
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    Print ""
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    Print "Files found for merging:" 53_Hl]#qZ  
    For Each curFile In fList ~"gA,e-)  
        Print Chr(9) & curFile JhYe6y[q  
    Next `Uq#W+r,  
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    'Split the first text file name found to get the sample name.  First file should be 0-0 measurement. DmK57V4L^  
    Dim nameArray() As String, sampName As String eNh39er  
    nameArray = Split(fList(0)," 0-0.txt") ,};&tR  
    sampName  = nameArray(0) t}_r]E,{u  
    Print "" _r#Z}HK  
    Print "Sample name: " & Chr(9) & sampName $L`d&$Vh  
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    'Open an output file and write the FRED header data `K"L /I9  
    Dim outFile As String /*~EO{o  
    outFile = cDir & sampName & "_FRED.txt" +SzU  
    Open outFile For Output As #1 &/Z /Y ]  
    Print #1, "type bsdf_data" f^3*)Ni  
    Print #1, "format angles=deg bsdf=value scale=1" a9e>iU  
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    'Loop the file list, skip the two header lines and write the remaining data to file 2F
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    Dim lineArray() As String, curLine As Long E#RDqL*J  
    For Each curFile In fList  y`iBFC;_  
        Print "Merging data from file " & curFile $V
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        ReadFile( cDir & curFile, lineArray ) MBK^FR-K  
        For curLine = 2 To UBound(lineArray) Gf6p'(\zun  
            Print #1, lineArray(curLine) ]2A^1Del  
        Next B^=-Z8  
    Next -12UN(&&Z  
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    'Close the output file cdH>n)  
    Close #1 Vsr.=Nd=  
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    Print "Finished merging RPC data for sample " & sampName Q>qUk@  
    Print "FRED formatted data file: " & Chr(9) & outFile >tS'Q`R
 
End Sub AF{\6<m  
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'Utility function to read the contents of a file into an array of strings. 3m[vXr?  
Function ReadFile(ByVal fileName As String, _ MR7}s4o  
                  ByRef lineArray() As String) As Long 5&g@3j]  
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    ReadFile = -1 -/B+T>[nTb  
    Dim oFSO As Object f^ZRT@`O  
    Set oFSO = CreateObject("Scripting.FileSystemObject") wSL}`CgU  
    Erase lineArray C.:<-xo  
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    Dim fid As Long eu|YCYj)g  
    If oFSO.fileexists( fileName ) Then !.$I["/=  
        fid = FreeFile() m,28u3@r  
        Open fileName For Input As fid 1#g2A0U,  
        lineArray = Split(Input(LOF(fid), fid), vbCrLf) X56q-|  
        Close fid T.F!+  
    End If g9p
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    Set oFSO = Nothing yf)%%&  
    Return UBound( lineArray ) yF:1( 4  
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End Function S>+|OCl";  
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Sub GetFileList( ByVal in_dir As String, _ g'f@H-KCD  
                 ByRef in_flist() As String ) N];NAMp  
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    'Redimension the file list array 68|E9^`l  
    Erase in_flist ;V_e>TyG  
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    'Tracks how many files are found w(Ovr`o?9t  
    Dim fCount As Long "!P3R1;%  
    fCount = 0 ;O5zUl-`  
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    'Recurse directory and search for text files n80?N}  
    Dim f As String m@j?za9s  
    f = Dir$(in_dir & "*.txt") "^[ 'y7i  
    While f <> "" P:S.~Jq  
        ReDim Preserve in_flist(fCount) Po;W'7"Po`  
        in_flist(fCount) = f 7"D",1h  
        fCount += 1 BVQqY$>  
        f = Dir$() 3NqB <J  
    Wend /N+dQe  
    ReDim Preserve in_flist(fCount-1) P5V}#;v  
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End Sub #MkTkm&r