Which change would most directly improve spatial resolution of the imaging system?

Which change would most directly improve spatial resolution of the imaging system?

• A. Increasing the number of detector elements (dexels)
• B. Increasing exposure time
• C. Increasing screen brightness
• D. Increasing film speed

Answer: (A)

Spatial resolution hinges on how finely the image is sampled by the detector. Each detector element, or dexel, captures light from a small area of the scene. By increasing the number of dexels, you shrink the area each one covers and raise the sampling density. More sampling elements mean the system can distinguish smaller changes in brightness across the image, which directly improves the ability to resolve fine details. Exposing longer increases the total signal and can reduce noise, but it doesn’t change how large the sampling elements are or how finely the image is sampled. Similarly, increasing screen brightness or film speed changes exposure or contrast and graininess rather than the sampling geometry, so they don’t directly improve spatial resolution.

Spatial resolution hinges on how finely the image is sampled by the detector. Each detector element, or dexel, captures light from a small area of the scene. By increasing the number of dexels, you shrink the area each one covers and raise the sampling density. More sampling elements mean the system can distinguish smaller changes in brightness across the image, which directly improves the ability to resolve fine details.

Exposing longer increases the total signal and can reduce noise, but it doesn’t change how large the sampling elements are or how finely the image is sampled. Similarly, increasing screen brightness or film speed changes exposure or contrast and graininess rather than the sampling geometry, so they don’t directly improve spatial resolution.