Optical Beam Control

Chapter 4Sources of Aberrations

An optical beam is a directed flow of light distinguished by a specific spatial profile and directionality. An optical beam may encounter various sources of aberration that can affect both its spatial profile and direction. This chapter examines the various sources of aberrations frequently observed in beam control systems.

4.1 Vibration and Jitter

Optical vibration and jitter refer to the periodic and random oscillations and perturbations in the position of an optical beam, particularly in the angular position of the beam that affects the beam propagation performances. There are many factors that can cause optical vibrations and jitter, including vibration in optical components, fluctuations in the optical path, mechanical vibrations, thermal changes in the environment, and atmospheric turbulence. Managing optical vibration and jitter is crucial for ensuring the precision and reliability of optical beam control systems.

4.1.1 Platform Jitter

Platform jitter is the common source of optical jitter encompassing many aberration sources present in the beam control system platform. The platform jitter is a result of random vibration of many different frequency components as well as narrowband frequency vibrations due to the rotating components and structural vibrations of the platform. Platform jitter is often represented by the power spectral density (PSD) of vibration signal power against spectrum of frequencies. For a window of with the ...