The near-edge structure in the x-ray absorption coefficient of an element is affected by chemistry and local environment. Experiments demonstrate that this property can be exploited in x-ray imaging both to identify and enhance the detectability of different chemical states of the same element. Chemical contrast images are obtained by digital subtraction of absorption images taken at carefully selected energy values.
© 1986 Optical Society of America
John Kinney, Quintin Johnson, Monte C. Nichols, Ulrich Bonse, and Rudolf Nusshardt, "Elemental and chemical-state imaging using synchrotron radiation," Appl. Opt. 25, 4583-4585 (1986)