This RPF(u) generator is based upon the following article:
Wu X and Liu H. "A new theory of phase-contrast x-ray imaging based on Wigner distributions." Med Phys. 2004 Sept;31(9):2378-84.
The purpose of this site is to educate residents and graduate students who want to play around with these types of calculations. I had to make some approximations, but the values should come close to the true values. Use at your own risk. There are no guarantees here. You should read the above article and understand what you are getting if you plan to use these results for anything other than your own enjoyment. Also, if you use them for anything scientific, please cite the Wu and Liu article and verify the calculations on your own.
The program also makes use of my radiography spectrum generator, which is itself based upon a published article (by Boone and Seibert) which you should also cite if you do anything scientific with this program. You should also read my remarks on the program and confirm its calculations on your own.
Currently, the program allows only a tungsten source and all attenuation and filtering is in mmAl. I am working on a version that will allow different mammography x-ray sources as well as different attenuators and filters.
Note that this function requires the exit spectrum, so you need to account for the difference in your mmAl if the object has any appreciable attenuation.