[分享]RPC Photonics扩散片BSDF [复制链接]

摘要： f\vMdY  
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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。 N`J]k B7  
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背景： -!QVM\t  
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。 QAzwNXE+  
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。 z'&tmje[?  
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步骤 A~
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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。 xnOd$]  
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2、 将     http://fred-kb.photonengr.com/wp-content/uploads/sites/2/2015/06/constructRpcScatterFile.frs脚本文件放在步骤1中的文件下。（脚本代码放在了本文的最后） 7{lWg x  
3、 打开FRED并运行脚本文件，会输出如下“<SAMPLE>_FRED.txt”格式，<SAMPLE>即为RPC Photonics散射片数据集 ?mHu eX  
例如下所示： 2jF}n*[OW  
Sample name:  EDF-C1-56 DX_?-jw})f  
Merging data from file EDF-C1-56 0-0.txt xzXNcQ  
Finished merging RPC data for sample EDF-C1-56 3Z}v%=5 "  
FRED formatted data file:  D:\FRED\散射片数据\EDF-C1-56_FRED.txt _0|@B8!J?  
4、 生成了FRED可识别的文件后，将散射模型导入到FRED里面 QlMv_|`9  
a. 创建一个新的散射库 N4l}5(e  
b. 散射模型命名 _<%YLv  
c. 改变散射模型为“Tabulated BSDF”. watTV\b  
d. 在File框出右键选择“Replace With Data From a File”, 选择步骤三生成的数据文件（如EDF-C1-56_FRED.txt ） 88KQ) NU  
e. 切换为“Varies w/angle” 选项（假定所有的RPC Photonics datasets 数据有多个测试角度。 12@Ge]  
f. 在底部的对话框中，选择透射散射、反射停并且你需要终止入射光线， ?sv[vR(  
g. 点击OK WK5B8u*<  
5、 数据输入后，可点击“Plot”按钮验证BSDF模型及总的散射值 E[Q2ZqhgbP  
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脚本代码： VwKfM MI8  
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'#Language "WWB-COM" 7Ue&y8Yf  
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Option Explicit &2nICAN[  
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Sub Main cB)tfS4)  
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    'Cleanup O^n\lik  
    ClearOutputWindow() }.1}yz^y  
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    Print "Merging RPC Photonics BSDF Data Files" cTQ._|M  
    SetTextColor(255,0,0) :F_>`{  
    Print "Note: Script should be located in the same folder as the BSDF TXT files." ZnBGNr  
    Print "Note: Do not run this script multiple times without deleting the output file between executions." i|rCGa0}  
    SetTextColor(0,0,0) z31g"  
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    'Current directory of this script (should be the same as the text files being merged) oB(9{6@N  
    Dim cDir As String .kTOG'K\e  
    cDir = MacroDir$ & "\" Qxfds`4V9i  
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    'Array which will be populated with the list of files to be merged ,$Cr9R&/  
    Dim fList() As String, curFile As String H<tU[U=G  
    GetFileList( cDir, fList ) b7y#uL1AE  
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    Print "" a'g&1N0Rc  
    Print "Files found for merging:" T 0qM"  
    For Each curFile In fList u2IU/z8 ^  
        Print Chr(9) & curFile 2%|n}V[  
    Next .7M.bpmqE  
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    'Split the first text file name found to get the sample name.  First file should be 0-0 measurement. 1\)C;c
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    Dim nameArray() As String, sampName As String Jl1\*1"  
    nameArray = Split(fList(0)," 0-0.txt") yMD3h$w3a  
    sampName  = nameArray(0) ??P%.  
    Print "" IBUFXzl  
    Print "Sample name: " & Chr(9) & sampName >2F9Tz,3  
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    'Open an output file and write the FRED header data \;iOQqv0&  
    Dim outFile As String j'OXT<n*  
    outFile = cDir & sampName & "_FRED.txt" BC5R$W.e  
    Open outFile For Output As #1 4|4 *rhwp  
    Print #1, "type bsdf_data" \}\# fg  
    Print #1, "format angles=deg bsdf=value scale=1" u08j9) ,4  
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    'Loop the file list, skip the two header lines and write the remaining data to file ?mF:L"i  
    Dim lineArray() As String, curLine As Long NV==[$(r  
    For Each curFile In fList U5OFw+J  
        Print "Merging data from file " & curFile 5A^8?,F@  
        ReadFile( cDir & curFile, lineArray ) / U!xh3  
        For curLine = 2 To UBound(lineArray) HCx0'|J  
            Print #1, lineArray(curLine) Mf !S'\  
        Next bc NyB$S  
    Next Z|fi$2k0!  
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    'Close the output file 1Y%lt5,*  
    Close #1 .V\~#Ro$G  
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    Print "Finished merging RPC data for sample " & sampName tvBLfqIr  
    Print "FRED formatted data file: " & Chr(9) & outFile ^=a:{["@!  
End Sub pMY7{z  
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'Utility function to read the contents of a file into an array of strings. &gr  T@  
Function ReadFile(ByVal fileName As String, _ S(^YTb7  
                  ByRef lineArray() As String) As Long /q8B | (U  
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    ReadFile = -1 -8vGvI>  
    Dim oFSO As Object @BPQ >  
    Set oFSO = CreateObject("Scripting.FileSystemObject") K4o']{:U  
    Erase lineArray VbTX;?  
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    Dim fid As Long qu!x#OY+  
    If oFSO.fileexists( fileName ) Then /sn }Q-Zy2  
        fid = FreeFile() 5!pNo*QK  
        Open fileName For Input As fid O3)B]!xL  
        lineArray = Split(Input(LOF(fid), fid), vbCrLf) df {\O*6  
        Close fid nf[KD,f  
    End If 0l/7JH_@V  
    Set oFSO = Nothing K9Onjs%U  
    Return UBound( lineArray ) Y]Z&  
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End Function >5?c93?  
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Sub GetFileList( ByVal in_dir As String, _ bxO[y<|XL  
                 ByRef in_flist() As String ) ^hr# 1  
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    'Redimension the file list array D=Nt0y  
    Erase in_flist Q@8(e&{#W  
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    'Tracks how many files are found :4x6dYNU  
    Dim fCount As Long F_i"v5#  
    fCount = 0 G$)tp^%]  
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    'Recurse directory and search for text files IwS<p-  
    Dim f As String t;0]d7ey'  
    f = Dir$(in_dir & "*.txt") YXmy-o>  
    While f <> "" \zBZ$5 rE  
        ReDim Preserve in_flist(fCount) KY0<N9{  
        in_flist(fCount) = f XMykUr e|  
        fCount += 1 A>315!d"  
        f = Dir$() ;49sou  
    Wend ydRS\l  
    ReDim Preserve in_flist(fCount-1) ;j[
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End Sub 1}SON4U  
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