Three-mirror anastigmatic five-meter aperture telescope and camera optics for CMB-S4

The next-generation ground-based cosmic microwave background (CMB) experiment, CMB-S4 will map the cosmic microwave background in degree and arcminute angular scales. Inflationary science benefits from the use of a large-aperture, arcminute resolution delensing survey, able to observe a large field of view of 9 degrees at wavelengths as short as $\lambda = 1 .1$ mm. In this work we review the optical design of the three-mirror anastigmatic large-aperture CMB-S4 telescope and its array of optics tubes. This optical system is capable mapping the CMB with unprecedented levels of sensitivity.