What type of grid is the cheapest?

• A. Crossed
• B. Parallel
• C. Focused
• D. Variable

Answer: (B)

The main idea here is how grid design affects cost. A parallel (non-focused) grid uses a simple, single set of evenly spaced lead strips without any focusing mechanism. That simplicity makes manufacturing and handling cheaper, and it works across a range of source-to-image distances, so you don’t need special positioning or SID settings.

In contrast, focused grids are designed to match a specific beam geometry, requiring more precise construction and alignment; crossed grids stack two grids for greater scatter cleanup, which adds weight, complexity, and cost; and variable grids add even more specialized features and mechanisms. Because of its straightforward construction and broad compatibility with different setups, the parallel grid is the least expensive option.