Gaussianstrålen

Gaussianstrålen is a mathematical model used to describe the intensity distribution of a laser beam. It assumes that the electric field amplitude varies in a Gaussian profile across the beam's cross-section. This means the intensity is highest at the center of the beam and decreases smoothly as one moves away from the center. The shape of this Gaussian distribution is characterized by a single parameter, the beam waist ($w_0$), which represents the radial distance from the axis where the intensity drops to $1/e^2$ (approximately 13.5%) of its peak value.

The propagation of a Gaussian beam in free space is also well-defined. As it travels, the beam waist increases linearly with distance, causing the beam to diverge. This divergence is inversely proportional to the initial beam waist; a tighter beam diverges more rapidly. The radius of curvature of the wavefront also changes with distance. At the beam waist, the wavefront is planar, but it becomes spherical further away. This behavior is crucial for understanding how laser beams focus and how their properties change over distance.

Gaussianstrålen is a fundamental concept in optics and is widely used in various applications, including laser design, optical communication, and microscopy. While real laser beams are often approximations of the ideal Gaussian model, the Gaussian beam description provides a powerful and accurate framework for analyzing and predicting their behavior in many practical scenarios. Deviations from the ideal Gaussian profile can occur due to factors like optical aberrations or beam shaping elements.