Point Spread Function

A mathematical description of how a single point of light is spread or blurred by an optical system such as the human eye. The point spread function characterizes the degree and pattern of distortion introduced by optical aberrations. In accessibility research, PSFs are used to model how a person with visual impairments perceives images, enabling techniques like display pre-compensation where screen content is mathematically adjusted to counteract the user's specific pattern of visual blurring.