[技术]RPC Photonics扩散片BSDF [复制链接]

摘要： yG' 5:  
La2f]+sV  
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。 ;b`kN;s  
Z|#G+$"QV  
背景： KgH_-REN  
Thorlabs和RPC Photonics联手共同推出的新型漫射体及光束整形技术，可以解决其他技术的不足，大大改善了诸如光刻系统、有效固态照明，显示，背光，显示亮度增强和投影屏等大多数应用的性能。这项我们称之为工程漫射体（Engineered DiffusersTM）的新概念，与其他技术有许多不同。与诸如磨砂玻璃、乳色玻璃和全息元件等随机漫射体截然不同，工程漫射体要求对于每个散射中心，通常为微透镜单元，都进行控制。例如全息漫射体可以视为一组随机排列的透镜，但是通过全息曝光形成的类透镜效果只能通过静态方式进行控制：而无法单独操控每个微透镜单元，这也帮助解释了全息漫射体无法控制光的分布和轮廓。另一方面，在工程漫射体中，每个微透镜单元形成漫射体，由其凹形纵断面和在阵列中的位置所确定。同时，为了确保漫射体不受输入光束变化的影响，并且不产生衍射效果，微透镜单元的分布是随机的，根据产生相应的光束形状函数所选取的概率分布函数来确定。因此，工程漫射体同时保留了随机与确定性漫射体的优点，从而实现高性能的光束整形功能。 Jkx_5kk/\  
FRED是美国Photon Engineering 公司开发的光学工程仿真软件，其在杂散光分析中独特的算法、高效的准确性，使其与其它同类产品相比更具优势。本案例我们重点讲述如何由RPC Photonics的BSDF数据转为FRED可识别的散射数据。 *'-[J2  
"Wb>y*S   
]/#3 P  
wbpz,  
步骤 kEYkd@{  
(v,g=BS,  
1、 在http://www.rpcphotonics.com/bsdf-data-optical-diffusers/下载并解压BSDF数据到某一文件夹下，选择“Raw data”文件。 6"oG bte  
On~
w`  
F
(;=^w  
2、 将     http://fred-kb.photonengr.com/wp-content/uploads/sites/2/2015/06/constructRpcScatterFile.frs脚本文件放在步骤1中的文件下。（脚本代码放在了本文的最后） (rieg F  
3、 打开FRED并运行脚本文件，会输出如下“<SAMPLE>_FRED.txt”格式，<SAMPLE>即为RPC Photonics散射片数据集 T5_/*`F  
例如下所示： 20,}T)}Tm  
Sample name:  EDF-C1-56 Op_(10|  
Merging data from file EDF-C1-56 0-0.txt WvoJ^{\4N*  
Finished merging RPC data for sample EDF-C1-56 !h
ugn6  
FRED formatted data file:  D:\FRED\散射片数据\EDF-C1-56_FRED.txt H3xMoSs  
4、 生成了FRED可识别的文件后，将散射模型导入到FRED里面 3j6Am{9  
a. 创建一个新的散射库 "$I8EW/1  
b. 散射模型命名 ,%T sfB  
c. 改变散射模型为“Tabulated BSDF”. <~bvfA=  
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 ） ii5dTimRJ  
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。 l9Av@|  
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， Mp3nR5@d$  
g. 点击OK 0sP*ChY5S  
5、 数据输入后，可点击“Plot”按钮验证BSDF模型及总的散射值 "Ng%"N
z  
grxlGS~Q  
D &Bdl5g  
脚本代码： 8U)*kmq  
x+bC\,q  
'#Language "WWB-COM" 8zO;=R A7%  
Tr.u'b(  
Option Explicit O~OM.:al&  
XY,!v
LjL  
Sub Main P_.zp5>  
B!x7oD9  
    'Cleanup ^2`*1el  
    ClearOutputWindow() 7Tc^}Q  
!!<H*9]+W;  
    Print "Merging RPC Photonics BSDF Data Files" [{q])P;  
    SetTextColor(255,0,0) &a
'mh  
    Print "Note: Script should be located in the same folder as the BSDF TXT files." q\
G7T{t$.  
    Print "Note: Do not run this script multiple times without deleting the output file between executions." ?&JKq^9\I  
    SetTextColor(0,0,0) X?$"dqA  
sZ>0*S  
    'Current directory of this script (should be the same as the text files being merged) \'6%Ld5km  
    Dim cDir As String pG^>y0  
    cDir = MacroDir$ & "\" >x*ef]aS  
`hDH7u!U.  
    'Array which will be populated with the list of files to be merged Pyp#'du>  
    Dim fList() As String, curFile As String
LO;6g~(1  
    GetFileList( cDir, fList ) ID~}pEQ  
ncpNesB  
    Print "" GGU>={D)  
    Print "Files found for merging:" /[I#3|  
    For Each curFile In fList qm6X5T  
        Print Chr(9) & curFile Ce:w^P+  
    Next r-AD*h@QZ  
' 7H"ezt  
    'Split the first text file name found to get the sample name.  First file should be 0-0 measurement. eyuQ}
R  
    Dim nameArray() As String, sampName As String "XLFw;o  
    nameArray = Split(fList(0)," 0-0.txt") K2gF;(  
    sampName  = nameArray(0) hO2W!68
 
    Print "" hf:\^w  
    Print "Sample name: " & Chr(9) & sampName =@P]eK/  
YRyaOrl$<  
    'Open an output file and write the FRED header data g*;zVi  
    Dim outFile As String bAEwjZ  
    outFile = cDir & sampName & "_FRED.txt" P@0J!  
    Open outFile For Output As #1 z:;yx  
    Print #1, "type bsdf_data" nP0rg  
    Print #1, "format angles=deg bsdf=value scale=1" ~{ucr#]C  
@!*I mN
MI  
    'Loop the file list, skip the two header lines and write the remaining data to file Z3f}'vr  
    Dim lineArray() As String, curLine As Long ZU;nXqjc  
    For Each curFile In fList xk7VuS*  
        Print "Merging data from file " & curFile L=gG23U&  
        ReadFile( cDir & curFile, lineArray ) jt0f*eYE8  
        For curLine = 2 To UBound(lineArray) ) D5JA`  
            Print #1, lineArray(curLine) V6&6I  
        Next U U3o(Yq  
    Next _
q}^#-  
yeLd,M/I  
    'Close the output file EUbyQL  
    Close #1 mZ g'  
Yo\%53w/  
    Print "Finished merging RPC data for sample " & sampName -d[Gy- J  
    Print "FRED formatted data file: " & Chr(9) & outFile =vsvx{o?  
End Sub P}w0=  
x b!&'cw  
'Utility function to read the contents of a file into an array of strings. !$p E=~1C  
Function ReadFile(ByVal fileName As String, _ ,MUgww!.  
                  ByRef lineArray() As String) As Long SP;1XXlL  
|(=b  
    ReadFile = -1 #&Rx?V  
    Dim oFSO As Object 1]"S?  
    Set oFSO = CreateObject("Scripting.FileSystemObject") ri49r*_1  
    Erase lineArray usw(]CnH  
h*?]A  
    Dim fid As Long q!WiX|P  
    If oFSO.fileexists( fileName ) Then B.}j1Bb  
        fid = FreeFile() NCVhWD21|  
        Open fileName For Input As fid ++BQ==@  
        lineArray = Split(Input(LOF(fid), fid), vbCrLf) 2BO"mc<#$  
        Close fid ,L; y>::1  
    End If 7 iQa)8,  
    Set oFSO = Nothing v7<r-<I[  
    Return UBound( lineArray ) 5}2148  
@%8$k[
  
End Function |$[.X3i  
rxOvYF  
Sub GetFileList( ByVal in_dir As String, _ 6 )lWuY]e  
                 ByRef in_flist() As String ) q:mqA$n  
x??H%'rP  
    'Redimension the file list array Wu)An  
    Erase in_flist \"P$*y4Le  
]?_V+F  
    'Tracks how many files are found =WK's8FB;8  
    Dim fCount As Long vofBS   
    fCount = 0 b@B\2BT  
d!y_N&z|(  
    'Recurse directory and search for text files =<Ss&p>  
    Dim f As String 10tt':  
    f = Dir$(in_dir & "*.txt") &(NW_<(  
    While f <> "" VqS1n  
        ReDim Preserve in_flist(fCount) o97*3W]  
        in_flist(fCount) = f h5lngw  
        fCount += 1 >[<f\BN|  
        f = Dir$() B %  
    Wend Z& bIjp  
    ReDim Preserve in_flist(fCount-1) :`S\p[5  
HFX,EE  
End Sub 58]t iP"