For the highest spatial resolution, which combination should be used?

• A. Small matrix and low pitch
• B. Small matrix and high pitch
• C. Large matrix and high pitch
• D. Large matrix and low pitch

Answer: (D)

Highest spatial resolution comes from making the pixels as small as possible and sampling the image as densely as possible. Pixel size is set by the field of view divided by how many pixels across the image area (the matrix size). A larger matrix means more pixels, so each pixel covers a smaller area, which improves the ability to distinguish fine details. Pitch is the spacing between detector elements; smaller pitch means elements are closer together, reducing gaps and allowing finer sampling of the image. So combining a large matrix with a low pitch yields the smallest pixels and the most tightly packed sampling, giving the highest spatial resolution. A small matrix would smear details with larger pixels, and a high pitch would introduce bigger gaps between elements, degrading resolution even if the matrix is large.