Noise analysis in isolation of iodine using three energies.

The Poisson noise inherent in multispectral x-ray imaging systems is formulated to give the SNR under a limited exposure constraint. The SNR value is maximized with respect to the exposure partition among different x-ray energies. The study shows how to choose suitable spectra and the dose weights. The robustness of these dose weights is also demonstrated for systems of varying bone and tissue contents.