The Gouy phase, named after the French physicist Louis Gouy, refers to the additional phase shift experienced by a light wave that is focused by a lens or passes through a focus in comparison to a plane wave. This phenomenon is particularly relevant in the field of optics.
When light passes through or is focused by a lens, the wavefronts experience distortion due to the curvature of the lens. The Gouy phase is the resulting phase shift in the light’s wavefronts. It is associated with the focusing of light and is dependent on the wavelength of the light and the characteristics of the optical system.
The Gouy phase is most noticeable in the vicinity of the focal point of a lens. As light converges to the focus, the phase of the wave is modified, leading to variations in the intensity and interference patterns. Understanding the Gouy phase is crucial in precision optics and laser applications where accurate control of phase relationships is necessary.
