Which optical effect enabled Ibn al-Haytham to more accurately describe the human vision process?

💡 Explanation

When light passes through a small hole into a dark room—'camera obscura'—an inverted image forms because rectilinear propagation projects the scene. Therefore this projection concept allowed Ibn al-Haytham to demonstrate that vision occurs through light entering the eye, not emanating from it, contravening prior beliefs involving intromission or extramission theories, which did not account for image formation.

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