Point spread function (PSF) is a fundamental concept in optics and imaging that describes how a point source of light is spread out or blurred in an image. It is a mathematical function that characterizes the response of an imaging system to a point source of light. The PSF is determined by various factors such as the optical system's design, aberrations, diffraction effects, and other physical properties. Understanding the PSF is crucial in image processing and analysis as it affects the resolution, sharpness, and overall quality of an image. Researchers typically study the PSF to optimize imaging systems, correct aberrations, deconvolve images, and improve image quality. By analyzing and characterizing the PSF, researchers can better understand the limitations and capabilities of imaging systems and develop strategies to enhance image resolution and fidelity.