from omega-2theta (w-2t) you transfer to Q (1/Aengstroem)

[Qx,Qy] = 1/lambda([sin(2t-w)+sinw],[cosw-cos(2t-w)])

this is then scaled with the lattice constants (rlu means relative lattice units); your lattice constants are already used to create your reciprocal space map. You can calculate your lattice parameter from the 2theta value using Braggs formula.

For the question of software - it is unclear to me how your data looks in the first place; the images you present have already been processed. Also it is unclear which type of measurement you present.

Hi Dr. Frontzek,

Thanks for your answer! I now understand how they transfer. But what's the physical interpretation behind this equation? I guess the '1/lambda[sin(2t-w)+sinw]' part is related to Braggs formula 2 d sin(t)=n lambda, but i'm confused by '1/lambda [cosw-cos(2t-w)]'. 

For the data, it's '.XRDML' document, we now use software 'X'Pert Epitaxy.exe' to open it. In some papers, I saw they rotated (103) RSM image by some degrees (like below),  but in our software, we can't do that. Thus I was asking if there's other software. By the way, I don't know why they rotated the image, too. Could you give me some suggestions? Thank you very much!

I'm keenly interested in all the answers!

Do feel welcome to review and post your comments on some of these related RG & LI posts below.

Thanks for sharing the knowledge :-)

https://www.flickr.com/photos/85210325@N04/14348488010/in/album-72157645018820696/

https://www.researchgate.net/post/How_do_I_compute_b_Burgers_Vector_correctly_using_the_Hirsch_approach_to_computing_dislocation_density_employing_XRD_rocking_curve_profile_analysis?_tpcectx=profile_questions

https://www.researchgate.net/post/What_is_the_best_way_to_interpret_REAL_TIME_3D_X_Y_o-2TH_o_ph_ch_reciprocal_space_relative_intensity_data_from_HRXRD_rocking_curve_analyses?_tpcectx=profile_questions

https://www.linkedin.com/pulse/nano-structural-meaning-xrd-data-converting-bragg-condition-ananth?trk=mp-reader-card

https://www.linkedin.com/pulse/imaging-nanostructure-75mm-production-grade-sic-4h-wafers-ravi-ananth?trk=mp-reader-card