Distinguish, in X-ray imaging, how sharpness differs from contrast. sharpness: contrast:
A student examines X-ray absorption in a model arm. Figure 11.1 shows a cross-section of the model arm. Parallel X-ray beams travel along line MM and along line BB. The linear absorption coefficients for muscle and bone are $0.20\,\text{cm}^{-1}$ and $12\,\text{cm}^{-1}$ respectively. Calculate the ratio $\frac{\text{intensity of emergent X-ray beam from model}}{\text{intensity of incident X-ray beam on model}}$ for a parallel X-ray beam directed along the line MM.
Calculate the ratio $\frac{\text{intensity of emergent X-ray beam from model}}{\text{intensity of incident X-ray beam on model}}$ for a parallel X-ray beam directed along the line BB.
State, from your answers in (b), whether the X-ray image would be sharp.
State, from your answers in (b), whether the X-ray image would show good contrast.