| Astrophysics (Index) | About |
A cylindrical telescope is a telescope with cylindrical optical elements rather than the typical circularly-symmetric. Its lenses or reflectors are cylindrical, i.e., with the same cross-sectional shape along one of its dimensions. Radio telescopes have been developed like this, typically using phase information to electronically (possibly digitally) disentangle signals along the one dimension, by the same principles as used for phased arrays. An example cylindrical radio telescope, Ooty Radio Telescope, can be physically aimed across one dimension, tilting a long cylindrical reflector using an equatorial mount, able to do this for being located near the equator. Another example, Canadian Hydrogen Intensity Mapping Experiment (CHIME), is non-steerable, with fixed mounting, using the Earth's rotation to scan all the celestial sphere viewable from its location. The Tianlai Project is another such telescope in China. In each case, they benefit from the lower construction costs by eliminating some of the structures needed to aim. They also offer the potential to extract from a single observation's data, signals from more than a single direction.