[技术]RPC Photonics扩散片BSDF [复制链接]

摘要： Fe8X@63  
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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。 Zpd-ob  
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背景： 8vx ca]DcV  
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。 s}zR@ !`  
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。 |Iy;_8c  
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步骤 "P7OD^(x/  
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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。 {-)^?Zb @  
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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） |=5zI6pT  
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 r1~W(r.x  
例如下所示： 0hY3vBQ!  
Sample name:  EDF-C1-56 _DR@P(0>_  
Merging data from file EDF-C1-56 0-0.txt lhM5a \  
Finished merging RPC data for sample EDF-C1-56 Q g/Rw4[  
FRED formatted data file:  D:\FRED\散射片数据\EDF-C1-56_FRED.txt $uLTYu  
4、 生成了FRED可识别的文件后，将散射模型导入到FRED里面 O0}uY:B  
a. 创建一个新的散射库 ^*jwe^  
b. 散射模型命名 hy/g*>  
c. 改变散射模型为“Tabulated BSDF”. y,?=,x}o#  
d. 在File框出右键选择“Replace With Data From a File”, 选择步骤三生成的数据文件（如EDF-C1-56_FRED.txt ） 1_7p`Gxt[/  
e. 切换为“Varies w/angle” 选项（假定所有的RPC Photonics datasets 数据有多个测试角度。 p,=IL_  
f. 在底部的对话框中，选择透射散射、反射停并且你需要终止入射光线， =2q#- ,t  
g. 点击OK Up Z 9g"  
5、 数据输入后，可点击“Plot”按钮验证BSDF模型及总的散射值 4EYD5  
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脚本代码： !S~)U{SSK  
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'#Language "WWB-COM" V;^-EWNj  
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Option Explicit =LGM[Z3$s  
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Sub Main ts=D

  
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    'Cleanup r@JMf)a]  
    ClearOutputWindow() U_jW5mgsG  
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    Print "Merging RPC Photonics BSDF Data Files" :E{)yT  
    SetTextColor(255,0,0) =pzTB-
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    Print "Note: Script should be located in the same folder as the BSDF TXT files." e"1mdw"  
    Print "Note: Do not run this script multiple times without deleting the output file between executions." 7(5d$W  
    SetTextColor(0,0,0) uj;iE 9  
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    'Current directory of this script (should be the same as the text files being merged) y%|Ez  
    Dim cDir As String L@RnLaoQ  
    cDir = MacroDir$ & "\" C;ab-gh  
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    'Array which will be populated with the list of files to be merged ;{8 X+H  
    Dim fList() As String, curFile As String ke@OG! M/  
    GetFileList( cDir, fList ) vEjf|-Mb9  
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    Print "" Dhm;K$T  
    Print "Files found for merging:" uv5NqL&  
    For Each curFile In fList ty[%:eG#  
        Print Chr(9) & curFile I3Co   
    Next krGIE}5  
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    'Split the first text file name found to get the sample name.  First file should be 0-0 measurement. (4z_2a(Dl,  
    Dim nameArray() As String, sampName As String BgN^].z&  
    nameArray = Split(fList(0)," 0-0.txt") J_a2DM6d  
    sampName  = nameArray(0) ZK?V{X{";  
    Print ""  irh Z  
    Print "Sample name: " & Chr(9) & sampName };rEN`L  
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    'Open an output file and write the FRED header data m5/]+xdNX  
    Dim outFile As String "z6p=B"?3  
    outFile = cDir & sampName & "_FRED.txt" l_((3e[)  
    Open outFile For Output As #1 g[y&GCKY!=  
    Print #1, "type bsdf_data" Z$i?p;HnW  
    Print #1, "format angles=deg bsdf=value scale=1" QP"5A7=m  
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    'Loop the file list, skip the two header lines and write the remaining data to file V6>{k_0{V  
    Dim lineArray() As String, curLine As Long  "X=^MGV  
    For Each curFile In fList /g0' +DP  
        Print "Merging data from file " & curFile e`B!)Sr  
        ReadFile( cDir & curFile, lineArray ) 'xEomo#  
        For curLine = 2 To UBound(lineArray) s o: o b}  
            Print #1, lineArray(curLine) |-v/  
        Next '?90e4x3/  
    Next j
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    'Close the output file 2/ )~$0  
    Close #1 >;G7ty[RX7  
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    Print "Finished merging RPC data for sample " & sampName ]c\`EHN  
    Print "FRED formatted data file: " & Chr(9) & outFile ^tyqc8&  
End Sub R0w~ Z   
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'Utility function to read the contents of a file into an array of strings. PMiu "  
Function ReadFile(ByVal fileName As String, _ J>hjIN  
                  ByRef lineArray() As String) As Long TJcHqzcUc  
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    ReadFile = -1 R4D$)D  
    Dim oFSO As Object daB5E<?  
    Set oFSO = CreateObject("Scripting.FileSystemObject") zzC{I@b
 
    Erase lineArray eZL!Z!  
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    Dim fid As Long t[({KbIy  
    If oFSO.fileexists( fileName ) Then G=Xas"|  
        fid = FreeFile() ?+c-m+;wj  
        Open fileName For Input As fid E)'T
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        lineArray = Split(Input(LOF(fid), fid), vbCrLf) .F/l$4CQ  
        Close fid )):D&wlq  
    End If #pD=TMefC  
    Set oFSO = Nothing ) [)1  
    Return UBound( lineArray ) D.F1^9Q  
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End Function :p1_ij]ND  
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Sub GetFileList( ByVal in_dir As String, _ 25vq#sS]  
                 ByRef in_flist() As String ) `y"a>gHC  
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    'Redimension the file list array !(_qM  
    Erase in_flist 7*+tG7I @  
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    'Tracks how many files are found 5uM`4xkj  
    Dim fCount As Long DI :  
    fCount = 0 Z'wGZ(  
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    'Recurse directory and search for text files ?+]   
    Dim f As String %u?A>$Jn  
    f = Dir$(in_dir & "*.txt") Z1\=d=  
    While f <> "" yTWicW7i  
        ReDim Preserve in_flist(fCount) |UQGZ  
        in_flist(fCount) = f qz-lQ  
        fCount += 1 UJ)(Sw  
        f = Dir$() Z%{`j!!p  
    Wend ) Cm95,Y  
    ReDim Preserve in_flist(fCount-1) I_`$$-|
 
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End Sub |pT[ZT|}G