Which statement accurately describes how ERA size affects beam directionality?

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Multiple Choice

Which statement accurately describes how ERA size affects beam directionality?

Explanation:
Beam directionality is shaped by diffraction at the aperture. A larger ERA enlarges the opening the beam passes through, which reduces edge diffraction and keeps rays closer to parallel, producing a most collimated beam. In contrast, a smaller ERA tightens the opening, increasing edge diffraction and causing the beam to spread out more, making it more divergent. So a large ERA yields a more collimated beam.

Beam directionality is shaped by diffraction at the aperture. A larger ERA enlarges the opening the beam passes through, which reduces edge diffraction and keeps rays closer to parallel, producing a most collimated beam. In contrast, a smaller ERA tightens the opening, increasing edge diffraction and causing the beam to spread out more, making it more divergent. So a large ERA yields a more collimated beam.

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