[技术]RPC Photonics扩散片BSDF [复制链接]

摘要： &xExyz~`  
BFt> 9x]T  
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。 ` G kX  
NCD04U5y  
背景： f?)-}\[IR{  
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。 J9 I:Q<;  
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。 U
GatWj  
3iU=c&P  
U%/+B]6jP  
f)<6  
步骤 CNx8] _2  
&,)&%Sg[  
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。 onV>.7sG  
(QiAisE  
51.%;aY~z  
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） YHl;flv  
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 bs1Rvx1:J%  
例如下所示： q0\6F^;M  
Sample name:  EDF-C1-56 @KUWxFak  
Merging data from file EDF-C1-56 0-0.txt ABYcH]m  
Finished merging RPC data for sample EDF-C1-56 OB}Ib]  
FRED formatted data file:  D:\FRED\散射片数据\EDF-C1-56_FRED.txt EEL,^3KR  
4、 生成了FRED可识别的文件后，将散射模型导入到FRED里面 m)D|l1AtF  
a. 创建一个新的散射库 wS3'?PRX  
b. 散射模型命名 D3K8F@d  
c. 改变散射模型为“Tabulated BSDF”. r@,2E6xn  
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 ） >KKMcTOYY  
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。 JjS?  
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， |gY
^)9ei  
g. 点击OK E<*xx#p  
5、 数据输入后，可点击“Plot”按钮验证BSDF模型及总的散射值 J?$,c4;W2  
n._
-! WI  
_Bj":rzY  
脚本代码： |vzl. ^"-  
^d73Ig:8q  
'#Language "WWB-COM" pmYHUj #  
rU(+T0t?I  
Option Explicit uXl3k:_n  
f|oh.z_R  
Sub Main h zn6kbv  
p{dj~
&v  
    'Cleanup GsM<2@?  
    ClearOutputWindow() caX< n>  
1yY0dOoLG)  
    Print "Merging RPC Photonics BSDF Data Files" @9|hMo  
    SetTextColor(255,0,0) T&7qC=E#5  
    Print "Note: Script should be located in the same folder as the BSDF TXT files." E&:,oG2M  
    Print "Note: Do not run this script multiple times without deleting the output file between executions." o3}3p]S\  
    SetTextColor(0,0,0) % %UE+u@J  
q-d:TMkc  
    'Current directory of this script (should be the same as the text files being merged) IEvdV6{K  
    Dim cDir As String bi;1s'Y<D  
    cDir = MacroDir$ & "\" "tpSg  
L9#g)tf 8T  
    'Array which will be populated with the list of files to be merged C+&l< fM&  
    Dim fList() As String, curFile As String B4 }bVjs  
    GetFileList( cDir, fList ) "@

8li^  
18:%~>.!  
    Print "" lU8Hd|@-  
    Print "Files found for merging:" +m,yA mEEd  
    For Each curFile In fList )@bQu~Y  
        Print Chr(9) & curFile ,UE83j8D^  
    Next @pU)_d!pJ  
\Y}8S/]  
    'Split the first text file name found to get the sample name.  First file should be 0-0 measurement. ^5 Tqy(M  
    Dim nameArray() As String, sampName As String d m%8K6|  
    nameArray = Split(fList(0)," 0-0.txt") <1M-Ro?5k  
    sampName  = nameArray(0) Ozf@6\/t  
    Print "" ;gr9/Vl  
    Print "Sample name: " & Chr(9) & sampName r",GC]  
qJUK_6|3  
    'Open an output file and write the FRED header data @U
}1EC{A  
    Dim outFile As String Pk)1WK7E  
    outFile = cDir & sampName & "_FRED.txt" GWip-wI  
    Open outFile For Output As #1 u\JNr}bL  
    Print #1, "type bsdf_data" 4H]L~^CD  
    Print #1, "format angles=deg bsdf=value scale=1" uM6+?A9@l  
m`r(p"  
    'Loop the file list, skip the two header lines and write the remaining data to file t\ewHZG"  
    Dim lineArray() As String, curLine As Long jo@J}`\Zt  
    For Each curFile In fList N ZSSg2TX#  
        Print "Merging data from file " & curFile du^J2m{f  
        ReadFile( cDir & curFile, lineArray ) uu687|P
m  
        For curLine = 2 To UBound(lineArray) 45>?o  
            Print #1, lineArray(curLine) <2qr}K{'A  
        Next |ZBI *  
    Next lHX72s|V  
i~J'%a<Qp  
    'Close the output file Q]>.b%s[  
    Close #1 N]sAji*  

A3@6N(  
    Print "Finished merging RPC data for sample " & sampName czd~8WgOa  
    Print "FRED formatted data file: " & Chr(9) & outFile D}/vLw:v  
End Sub um0N)&iY  
0lR5<^B  
'Utility function to read the contents of a file into an array of strings. ~qOa\#x_  
Function ReadFile(ByVal fileName As String, _ [cp+i^f  
                  ByRef lineArray() As String) As Long L;I]OC^J  
CeC6hGR5  
    ReadFile = -1 }`~+]9<  
    Dim oFSO As Object 0"bcdG<}  
    Set oFSO = CreateObject("Scripting.FileSystemObject") @<&m|qtMsz  
    Erase lineArray %bfQ$a:  
~Jz6O U*z  
    Dim fid As Long N?"]  
    If oFSO.fileexists( fileName ) Then w+CA1q<  
        fid = FreeFile() kW&TJP+5*  
        Open fileName For Input As fid +; AZ+w]ZF  
        lineArray = Split(Input(LOF(fid), fid), vbCrLf) :20W\P<O!A  
        Close fid Jg|XH L)  
    End If 0:Ol7  
    Set oFSO = Nothing )hfpwdQ  
    Return UBound( lineArray ) >\3V a  
ZzT9j~  
End Function p=}Nn(  
@J`"[%U  
Sub GetFileList( ByVal in_dir As String, _ ,nDaqQ-C!!  
                 ByRef in_flist() As String ) :Fvrs( x  
SI-Ops~e  
    'Redimension the file list array >I&5j/&}+  
    Erase in_flist j eP  
!d0kV,F:  
    'Tracks how many files are found ;MdlwQ$`  
    Dim fCount As Long FQ5U$x.[P  
    fCount = 0 Z>5b;8  
~FG]wNgS  
    'Recurse directory and search for text files v z '&%(  
    Dim f As String [K0(RDV)%  
    f = Dir$(in_dir & "*.txt") cHt#us  
    While f <> "" wD'SPk5S?  
        ReDim Preserve in_flist(fCount) HCC#j9UN6  
        in_flist(fCount) = f 5C5sgR C  
        fCount += 1 ]-/VH
h  
        f = Dir$() ckE-",G  
    Wend Dwfu.ZJa  
    ReDim Preserve in_flist(fCount-1) b!5~7Ub.No  
b2&0Hx  
End Sub dVT$VQg