Injection laser system architecture, upgrades, and future at the National Ignition Facility

The front end of the National Ignition Facility (NIF) known as the Injection Laser System (ILS) has a 30-year history of development and phased upgrades. It continues to be modernized in support of enhanced NIF performance, reliability, availability, maintainability, and sustainability. This paper provides an overview of the ILS architecture, sub-systems, and their design features developed to meet specifications. The most impactful upgrades are reviewed including the first-generation Programmable Spatial Shaping (PSS) system, wavelength / bandwidth control, FM-AM mitigation and verification, and the High-Fidelity Pulse Shaping system. Future upgrades planned or in progress are discussed including the second-generation Programmable Spatial Shaping system, Diode-Pumped Multi-Pass Amplifier, and prospects for high bandwidth pulse shaping and/or spectral control.