Random pinhole attenuator for high-power laser beams

Abstract

The intensity attenuation of a high-power laser is a frequent task in the measurements of optical science. Laser intensity can be attenuated by inserting an optical element, such as a partial reflector, polarizer, or absorption filter. These devices are, however, not always easily applicable, especially in the case of ultra-high power lasers, because they can alter the characteristics of a laser beam or get easily damaged. In this study, we demonstrated that the intensity of a laser beam could be effectively attenuated using a random pinhole attenuator (RPA), a device with randomly distributed pinholes, without changing beam properties. With this device a multi-PW laser beam was successfully attenuated and the focused beam profile was measured without any alterations of its characteristics. Additionally, it was confirmed that the temporal profile of a laser pulse, including the spectral phase, was preserved. Consequently, the RPA possesses significant potential for a wide range of applications. © 2024 Cambridge University Press. All rights reserved.