[技术]RPC Photonics扩散片BSDF [复制链接]

摘要： I,.>tC  
eja_+`cJ  
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。 oc>,5 x  
M" %w9)@  
背景： Nf
Ki,^O  
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。 jF{zcYU  
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。 5G=2=E  
I%;xMtY1o  
G[)Q
GZ}8b  
3-srt^>w*  
步骤 ^#p Su  
 h9RG?r1  
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。 T/UhZ4(V  
}5FdX3YR  
M+9G^o)u  
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） #8QQZdC8`  
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 f_7a) 'V4  
例如下所示： c{7!:hi`x  
Sample name:  EDF-C1-56 D~G24k6b3  
Merging data from file EDF-C1-56 0-0.txt mn)kd  
Finished merging RPC data for sample EDF-C1-56 $-
EbJ  
FRED formatted data file:  D:\FRED\散射片数据\EDF-C1-56_FRED.txt '/J}T -,Z  
4、 生成了FRED可识别的文件后，将散射模型导入到FRED里面 ]]J2#mN:n  
a. 创建一个新的散射库 7kp$C?7K  
b. 散射模型命名 @or&GcQ*  
c. 改变散射模型为“Tabulated BSDF”. ^duNEu0*  
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 ） ! jm>  
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。 BC=U6>`/  
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， K1AI:$H  
g. 点击OK s+8 v7ZJ  
5、 数据输入后，可点击“Plot”按钮验证BSDF模型及总的散射值 DBI[OG9  
iP6$;Y{ZA  
*tC]Z&5  
脚本代码： 6hv4D`d;o  
4W &HUQ?^  
'#Language "WWB-COM" -{dsl|Dl  
'8R5?9"  
Option Explicit ]([:"j  
y w)q3zC  
Sub Main B`3RyM"J@  
G%_6"s  
    'Cleanup B#9rqC  
    ClearOutputWindow() 5-3`@
(/  
sS/#)/B  
    Print "Merging RPC Photonics BSDF Data Files" @AYO )Y8  
    SetTextColor(255,0,0) L8("1_  
    Print "Note: Script should be located in the same folder as the BSDF TXT files." l3dGe'  
    Print "Note: Do not run this script multiple times without deleting the output file between executions." u;rK.3o  
    SetTextColor(0,0,0) ,y@`wq>O  
`KBgVhS>  
    'Current directory of this script (should be the same as the text files being merged) %y;E1pva  
    Dim cDir As String g"gh2#!D  
    cDir = MacroDir$ & "\" %upnXRzw  
p_T>"v  
    'Array which will be populated with the list of files to be merged Ej\EuX  
    Dim fList() As String, curFile As String 2gLa4B-  
    GetFileList( cDir, fList ) O]rAo  
V9q
Za  
    Print "" {Wp+Y9c[  
    Print "Files found for merging:" aN9#ATE  
    For Each curFile In fList ~^jdiy5  
        Print Chr(9) & curFile JRQ{Q"`)  
    Next NMq#D$T  
CMI'y(GN  
    'Split the first text file name found to get the sample name.  First file should be 0-0 measurement. Itn7Kl  
    Dim nameArray() As String, sampName As String $U=E7JO  
    nameArray = Split(fList(0)," 0-0.txt") *K#7,*Oz  
    sampName  = nameArray(0) =\CJsS.  
    Print "" py#`  
    Print "Sample name: " & Chr(9) & sampName g3[Zh=+]E  
,M@
LtA3g  
    'Open an output file and write the FRED header data "JI FF_  
    Dim outFile As String vd>K=! J  
    outFile = cDir & sampName & "_FRED.txt" c`:
hE
Qs  
    Open outFile For Output As #1 {ctEjgiE  
    Print #1, "type bsdf_data" jIY   
    Print #1, "format angles=deg bsdf=value scale=1" *Z0Y:"  
c)H(w  
    'Loop the file list, skip the two header lines and write the remaining data to file ~AbnksR  
    Dim lineArray() As String, curLine As Long /Mk85C79  
    For Each curFile In fList GA&mM  
        Print "Merging data from file " & curFile QmQsNcF~z  
        ReadFile( cDir & curFile, lineArray ) $Pa7B]A,Ae  
        For curLine = 2 To UBound(lineArray) 5rG&Z5  
            Print #1, lineArray(curLine) ^X2U A{  
        Next Uh.XL=wY  
    Next HN'r ZAZ(  
-[-LR }u  
    'Close the output file ) V}q7\G~  
    Close #1 /Mq]WXq[V  
|||uTfrJ  
    Print "Finished merging RPC data for sample " & sampName a`}b'X:  
    Print "FRED formatted data file: " & Chr(9) & outFile }@IRReQ  
End Sub HnvE\t9`  
+ -e8MvP  
'Utility function to read the contents of a file into an array of strings. 8+^?<FKa  
Function ReadFile(ByVal fileName As String, _ rCcNu  
                  ByRef lineArray() As String) As Long {
"33 .^=  
zGz^T  
    ReadFile = -1 3#>;h
 
    Dim oFSO As Object >M.?qs4  
    Set oFSO = CreateObject("Scripting.FileSystemObject") t3 AZS0  
    Erase lineArray }g WSV  
8kZ~  
    Dim fid As Long 2A3;#v  
    If oFSO.fileexists( fileName ) Then 7I;Give{  
        fid = FreeFile() e_J_rx  
        Open fileName For Input As fid 9IL#\:d1  
        lineArray = Split(Input(LOF(fid), fid), vbCrLf) qB3{65  
        Close fid ^RkHdA  
    End If 02X~' To"  
    Set oFSO = Nothing _>HXQ6Hw  
    Return UBound( lineArray ) lo:]r.lX{  
*[*#cMZ   
End Function JH2?^h|{  
ErF;5ec  
Sub GetFileList( ByVal in_dir As String, _ ,=lMtW  
                 ByRef in_flist() As String ) 2F-!SI  
c1wM"  
    'Redimension the file list array ~BCSm]j  
    Erase in_flist c=H(*#  
w5jH#ja  
    'Tracks how many files are found 7dX1.}M<(  
    Dim fCount As Long `Oys&]vb  
    fCount = 0 oUZwZ_yKW  
3a#637%  
    'Recurse directory and search for text files ;^:~xJFx|  
    Dim f As String  3P/T`)V  
    f = Dir$(in_dir & "*.txt") }"fP,:n"KN  
    While f <> "" H7"I+qE-G  
        ReDim Preserve in_flist(fCount) U*/  
        in_flist(fCount) = f Y,WcHE  
        fCount += 1 +n9&q#ah  
        f = Dir$() &X_I^*  
    Wend 6\O4R  
    ReDim Preserve in_flist(fCount-1) Rjo6Pd{d<  
'm}~  
End Sub n5UcivyX