%0 Journal Article %T A large-aperture telescope to map the CMB 10X faster %A Michael D. Niemack %J Physics %D 2015 %I arXiv %X Current large-aperture cosmic microwave background (CMB) telescopes have nearly maximized the number of detectors that can be illuminated while maintaining diffraction-limited image quality. The polarization-sensitive detector arrays being deployed in these telescopes in the next few years will have roughly $10^4$ detectors. Increasing the mapping speed of future instruments by at least an order of magnitude is important to enable precise probes of the inflationary paradigm in the first fraction of a second after the big bang and provide strong constraints on cosmological parameters. This paper introduces new crossed Dragone telescope and receiver optics designs that increase the usable diffraction-limited field-of-view, and therefore the mapping speed, by over an order of magnitude to enable high efficiency illumination of $>10^5$ detectors in a next generation CMB telescope. %U http://arxiv.org/abs/1511.04506v1