[技术]RPC Photonics扩散片BSDF [复制链接]

摘要： C$rZn%dp(  
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RPC Photonics公司有高品质的的工程漫射体BSDF测试数据，但它对于FRED帮助甚少，下面这个步骤描述了如何利用FRED脚本转换RPC Photonics提供的TXT文件，并将数据直接应用到FRED的Tabulated scatter 散射模型。 2R.YHj  
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背景： 92eS*x2@  
Thorlabs和RPC Photonics联手共同推出的新型漫射体及光束整形技术，可以解决其他技术的不足，大大改善了诸如光刻系统、有效固态照明，显示，背光，显示亮度增强和投影屏等大多数应用的性能。这项我们称之为工程漫射体（Engineered DiffusersTM）的新概念，与其他技术有许多不同。与诸如磨砂玻璃、乳色玻璃和全息元件等随机漫射体截然不同，工程漫射体要求对于每个散射中心，通常为微透镜单元，都进行控制。例如全息漫射体可以视为一组随机排列的透镜，但是通过全息曝光形成的类透镜效果只能通过静态方式进行控制：而无法单独操控每个微透镜单元，这也帮助解释了全息漫射体无法控制光的分布和轮廓。另一方面，在工程漫射体中，每个微透镜单元形成漫射体，由其凹形纵断面和在阵列中的位置所确定。同时，为了确保漫射体不受输入光束变化的影响，并且不产生衍射效果，微透镜单元的分布是随机的，根据产生相应的光束形状函数所选取的概率分布函数来确定。因此，工程漫射体同时保留了随机与确定性漫射体的优点，从而实现高性能的光束整形功能。 T*LbZ"A  
FRED是美国Photon Engineering 公司开发的光学工程仿真软件，其在杂散光分析中独特的算法、高效的准确性，使其与其它同类产品相比更具优势。本案例我们重点讲述如何由RPC Photonics的BSDF数据转为FRED可识别的散射数据。 %M~Ugv_4v  
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步骤 vzy/R
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1、 在http://www.rpcphotonics.com/bsdf-data-optical-diffusers/下载并解压BSDF数据到某一文件夹下，选择“Raw data”文件。 c1b@3  
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2、 将     http://fred-kb.photonengr.com/wp-content/uploads/sites/2/2015/06/constructRpcScatterFile.frs脚本文件放在步骤1中的文件下。（脚本代码放在了本文的最后） &Gxk
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3、 打开FRED并运行脚本文件，会输出如下“<SAMPLE>_FRED.txt”格式，<SAMPLE>即为RPC Photonics散射片数据集 m;8_A|$A  
例如下所示： %!LrC!6P4  
Sample name:  EDF-C1-56 } %rF}>$A  
Merging data from file EDF-C1-56 0-0.txt lD\lFN(:
 
Finished merging RPC data for sample EDF-C1-56 ])0&el3-  
FRED formatted data file:  D:\FRED\散射片数据\EDF-C1-56_FRED.txt @$Z5Ag!  
4、 生成了FRED可识别的文件后，将散射模型导入到FRED里面 Hk$|.TjzI  
a. 创建一个新的散射库 'X{7b <  
b. 散射模型命名 D3BX[  
c. 改变散射模型为“Tabulated BSDF”. ;Mw9}Reh@  
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 ） nL@P{,J  
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。 oM QH-\(}  
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， 9?l( }S`  
g. 点击OK 0jE,=<W0>  
5、 数据输入后，可点击“Plot”按钮验证BSDF模型及总的散射值 tz._*n83  
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脚本代码： W:hR81ci  
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'#Language "WWB-COM" &)<]AG.vd!  
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Option Explicit m,qU})  
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Sub Main Z A7u66  
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    'Cleanup $;"@;Lj%,  
    ClearOutputWindow() ?9 2+(s  
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    Print "Merging RPC Photonics BSDF Data Files" Ab8~'<F$B  
    SetTextColor(255,0,0) F1gDeLmJ  
    Print "Note: Script should be located in the same folder as the BSDF TXT files." {ZN{$Ad3/  
    Print "Note: Do not run this script multiple times without deleting the output file between executions." 6R dfF$f
 
    SetTextColor(0,0,0) ukvz#hdE  
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    'Current directory of this script (should be the same as the text files being merged) }MuXN<DDb  
    Dim cDir As String i1C]bUXA  
    cDir = MacroDir$ & "\" ]!0 BMZmf  
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    'Array which will be populated with the list of files to be merged +1F@vag7  
    Dim fList() As String, curFile As String HwM:bY N  
    GetFileList( cDir, fList ) }me]?en_Ra  
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    Print "" Br1JZHgA  
    Print "Files found for merging:" )bPwB.}kq  
    For Each curFile In fList st/Tb/  
        Print Chr(9) & curFile 9`-ofwr'|  
    Next Q]a5]:0  
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    'Split the first text file name found to get the sample name.  First file should be 0-0 measurement. `[57U,v  
    Dim nameArray() As String, sampName As String S3btx9y{  
    nameArray = Split(fList(0)," 0-0.txt") Wb/@~!+i`  
    sampName  = nameArray(0) Qh?q0VKU^  
    Print "" [Z~>7ayF+)  
    Print "Sample name: " & Chr(9) & sampName //K]zu  
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    'Open an output file and write the FRED header data m6+2rD  
    Dim outFile As String tJ2l_M^  
    outFile = cDir & sampName & "_FRED.txt" KDg!Y(m{  
    Open outFile For Output As #1 z8vFQO\I"  
    Print #1, "type bsdf_data" \`|,wLgH  
    Print #1, "format angles=deg bsdf=value scale=1" 7o0ej
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    'Loop the file list, skip the two header lines and write the remaining data to file WNlWigwYl  
    Dim lineArray() As String, curLine As Long T-f+<Cxf  
    For Each curFile In fList AUzJ:([V  
        Print "Merging data from file " & curFile '00DUUa  
        ReadFile( cDir & curFile, lineArray ) BRD>q4w  
        For curLine = 2 To UBound(lineArray) nLdI>c9R  
            Print #1, lineArray(curLine) >(:KEA  
        Next khc5h^0  
    Next /0Zwgxt4?7  
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    'Close the output file b>Vs5nY!  
    Close #1 gaTI:SKzc  
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    Print "Finished merging RPC data for sample " & sampName O_(J',++  
    Print "FRED formatted data file: " & Chr(9) & outFile }^)M)8zS  
End Sub  QqtFNG  
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'Utility function to read the contents of a file into an array of strings. `'+[Y;s_  
Function ReadFile(ByVal fileName As String, _ f^m8 4o'  
                  ByRef lineArray() As String) As Long s:wLEj+  
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    ReadFile = -1 k. px  
    Dim oFSO As Object }SUe 4r&4}  
    Set oFSO = CreateObject("Scripting.FileSystemObject") EDL<J1%  
    Erase lineArray ,i,f1XJ|  
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    Dim fid As Long evu@uq  
    If oFSO.fileexists( fileName ) Then <Pg.N  
        fid = FreeFile() \HTXl]  
        Open fileName For Input As fid GMB%
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        lineArray = Split(Input(LOF(fid), fid), vbCrLf) "1h|1'S50?  
        Close fid 3u+~
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    End If Z78&IbR  
    Set oFSO = Nothing ?}B_'NZ%  
    Return UBound( lineArray ) oAvL?2  
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End Function oNl_r:G
 
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Sub GetFileList( ByVal in_dir As String, _ =GFlaGD  
                 ByRef in_flist() As String ) o)Ob}j  
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    'Redimension the file list array "sL#)<%  
    Erase in_flist J}%&;uv  
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    'Tracks how many files are found olQ;XTa01F  
    Dim fCount As Long 9b()ck-\F#  
    fCount = 0 R &T(S
 
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    'Recurse directory and search for text files bWjW_$8  
    Dim f As String 
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    f = Dir$(in_dir & "*.txt") u=RF6V|  
    While f <> "" /v=MGX@r  
        ReDim Preserve in_flist(fCount) V4ayewVX  
        in_flist(fCount) = f } Tp!Ub\Cc  
        fCount += 1 (Cqhk:F  
        f = Dir$() Q6"r^wWx  
    Wend Yl>@(tu)|  
    ReDim Preserve in_flist(fCount-1) *J~N  
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End Sub .P-@ !Q5*