Which grid type has strips angled to coincide with beam divergence?

Which grid type has strips angled to coincide with beam divergence?

• A. Parallel
• B. Crosshatch
• C. Focused
• D. Rhombic

Answer: (C)

Grids are designed to match the geometry of the X-ray beam. Because the beam diverges from the focal spot, a grid whose lead strips are angled to follow that divergence helps keep the primary photons aligned with the grid openings across the image field. This is the focused grid. Its strips tilt so they converge toward the focal line, reducing grid cutoff and preserving image exposure at the intended distance. Other grids don’t angle the strips to match the beam’s divergence, so they’re more likely to absorb useful primary radiation at the edges or require exact positioning to avoid cutoff.

Grids are designed to match the geometry of the X-ray beam. Because the beam diverges from the focal spot, a grid whose lead strips are angled to follow that divergence helps keep the primary photons aligned with the grid openings across the image field. This is the focused grid. Its strips tilt so they converge toward the focal line, reducing grid cutoff and preserving image exposure at the intended distance. Other grids don’t angle the strips to match the beam’s divergence, so they’re more likely to absorb useful primary radiation at the edges or require exact positioning to avoid cutoff.