The Nancy Grace Roman Space Telescope (“Roman”) is NASA’s next flagship observatory. Launching in 2027, it will test theories of the accelerated expansion of the universe, as well as expand the census of exoplanets in our galaxy. These science objectives are enabled by Roman’s large field of view, agile survey capabilities, and excellent stability. The Roman optical system comprises an optical telescope assembly (OTA) and two instruments: the primary science wide-field instrument (WFI), and a technology demonstration coronagraph instrument (CGI). This paper will describe the optical system configuration and associated performance requirements and expectations, including summary results from Monte Carlo simulations of the end-to-end alignment, launch, and commissioning operations. We will describe the optical test and verification program, including stray light analysis and verification. We will also describe the use of focus-diverse phase retrieval during both test and commissioning ph
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