[技术]RPC Photonics扩散片BSDF [复制链接]

摘要： Ag{iq(X  
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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。 Ec
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背景： |<:vY  
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。 u%w`:v7Yo(  
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。 B!vmQR*1  
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步骤 cWoPB _  
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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。 ZosP(Tdq  
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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） b )B?
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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 eeyHy"@  
例如下所示： !o:f$6EA~C  
Sample name:  EDF-C1-56 {phNds%  
Merging data from file EDF-C1-56 0-0.txt 28 ?\  
Finished merging RPC data for sample EDF-C1-56 bD/~eIcWL  
FRED formatted data file:  D:\FRED\散射片数据\EDF-C1-56_FRED.txt Y;?{|  
4、 生成了FRED可识别的文件后，将散射模型导入到FRED里面
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a. 创建一个新的散射库 ILGMMA_2  
b. 散射模型命名 ogyTO
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c. 改变散射模型为“Tabulated BSDF”. ;M)QwF1  
d. 在File框出右键选择“Replace With Data From a File”, 选择步骤三生成的数据文件（如EDF-C1-56_FRED.txt ） 9I}-[|`u  
e. 切换为“Varies w/angle” 选项（假定所有的RPC Photonics datasets 数据有多个测试角度。 ,P;Pm68V  
f. 在底部的对话框中，选择透射散射、反射停并且你需要终止入射光线， ;lHr =e7  
g. 点击OK #"@|f  
5、 数据输入后，可点击“Plot”按钮验证BSDF模型及总的散射值 x[a<mk  
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脚本代码： A"L&a l$i  
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'#Language "WWB-COM" MF5[lK9e  
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Option Explicit `@`CG[-9  
be.*#[  
Sub Main Y$"O VC  
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    'Cleanup E7rDa1  
    ClearOutputWindow() hb}+A=A=+  
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    Print "Merging RPC Photonics BSDF Data Files" _h{C_;a[_  
    SetTextColor(255,0,0) F(>Np2oi6  
    Print "Note: Script should be located in the same folder as the BSDF TXT files." N sXHO  
    Print "Note: Do not run this script multiple times without deleting the output file between executions." aA
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    SetTextColor(0,0,0) =l+yA>t|  
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    'Current directory of this script (should be the same as the text files being merged) ]'&
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    Dim cDir As String 0Tx6zO  
    cDir = MacroDir$ & "\" ZrpU <   
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    'Array which will be populated with the list of files to be merged y [}.yyye  
    Dim fList() As String, curFile As String ,o86}6Ag  
    GetFileList( cDir, fList ) eA2@Nkw~)  
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    Print "" g6j?,c|y  
    Print "Files found for merging:" ,E S0NA  
    For Each curFile In fList -t!~%_WCv  
        Print Chr(9) & curFile <:+x+4ru  
    Next ;U/&I3dzV  
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    'Split the first text file name found to get the sample name.  First file should be 0-0 measurement. )_YX DU  
    Dim nameArray() As String, sampName As String ]d$8f  
    nameArray = Split(fList(0)," 0-0.txt") +$ 'Zf0U  
    sampName  = nameArray(0) D4eDHq  
    Print "" oB(?_No7  
    Print "Sample name: " & Chr(9) & sampName u^^[Q2LDU}  
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    'Open an output file and write the FRED header data rV` #[d  
    Dim outFile As String DX#Nf""Pw  
    outFile = cDir & sampName & "_FRED.txt" em%4Ap  
    Open outFile For Output As #1 fK>L!=Q  
    Print #1, "type bsdf_data" W=N+V
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    Print #1, "format angles=deg bsdf=value scale=1" fDv2JdiU  
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    'Loop the file list, skip the two header lines and write the remaining data to file }T(D7|^R  
    Dim lineArray() As String, curLine As Long <sb~ ^B  
    For Each curFile In fList P)Jgs  
        Print "Merging data from file " & curFile K@ I9^b  
        ReadFile( cDir & curFile, lineArray ) b/+u4'"  
        For curLine = 2 To UBound(lineArray) f\|w'  
            Print #1, lineArray(curLine) )}Hpi<5N  
        Next D+rxT: d  
    Next )1?y 8_B  
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    'Close the output file T6\[iJI|  
    Close #1 h0g8*HY+}  
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    Print "Finished merging RPC data for sample " & sampName y6(Z`lx  
    Print "FRED formatted data file: " & Chr(9) & outFile hNC&T`.-~B  
End Sub h79}qU  
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'Utility function to read the contents of a file into an array of strings. qqjwJ!@P  
Function ReadFile(ByVal fileName As String, _ is?{MJZ_  
                  ByRef lineArray() As String) As Long ?g_3 [Fk  
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    ReadFile = -1 .73X3`P25  
    Dim oFSO As Object G<L;4nA)  
    Set oFSO = CreateObject("Scripting.FileSystemObject") HY56"LZ$(}  
    Erase lineArray E^B'4  
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    Dim fid As Long g@d*\ P)  
    If oFSO.fileexists( fileName ) Then Yj&F;_~  
        fid = FreeFile() u+9hL4  
        Open fileName For Input As fid tHU2/V:R  
        lineArray = Split(Input(LOF(fid), fid), vbCrLf) Ki;*u_4{  
        Close fid Akq2 d;  
    End If ) ;EBz  
    Set oFSO = Nothing P0;n9>g  
    Return UBound( lineArray ) {a =#B)6  
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End Function * `JYC  
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Sub GetFileList( ByVal in_dir As String, _ aS>u,=C  
                 ByRef in_flist() As String ) pE`})/?\*  
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    'Redimension the file list array >R'F,  
    Erase in_flist P9R9(quI  
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    'Tracks how many files are found [F+}V,  
    Dim fCount As Long 5tl< 3g`  
    fCount = 0 ncaT?~u j  
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    'Recurse directory and search for text files d9k0F OR1  
    Dim f As String R|'ybW'Y  
    f = Dir$(in_dir & "*.txt") lqy Qf$t  
    While f <> "" N"Z{5A  
        ReDim Preserve in_flist(fCount) hqD*z6aH  
        in_flist(fCount) = f D ;RiGW4  
        fCount += 1 Mc)}\{J  
        f = Dir$() W<'m:dq  
    Wend ~$c\JKH-  
    ReDim Preserve in_flist(fCount-1) &1Ok`_plO  
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End Sub B.=FSow