A first-generation CT scanner is used to image the object shown in Figure P6.2 (su...

A first-generation CT scanner is used to image the object shown in Figure P6.2 (surrounded by air). Suppose for E > 100 keV

Suppose that each incident photon burst is polychromatic, but has only two photon energies, and that there are 10⁶ photons at 100 keV, and 0.5 × 10⁶ at 140 keV.

(a) Calculate the incident intensity of the x-ray burst.

(b) Ignore the dimension of the detector in this part. Find the intensity Id as a function of x for the measured projection at θ = 0°. Sketch it.

(c) Calculate the local contrast of the middle square given the measured projection Id(x). What is the local contrast of the projection?

(d) Suppose the detector has a width of 1 cm. Find the measured projection Id(x) (x being a continuous variable) in this case, and sketch it. Will this change affect the local contrast? Explain.