This is the largest solar instrument in the world. It also is the world's largest unobstructed aperture optical telescope, having a diameter of 1.6 meters. All-reflective optics with no windows, lenses or central obscuration.
Primary Uses: High-precision solar spectroscopy and polarimetry. Infrared spectroscopy and imaging (1-20 micrometers). Solar-stellar spectroscopy. Laboratory spectroscopy. Planetary and cometary spectroscopy. Terrestrial atmospheric spectroscopy and monitoring (including ozone and CFCs).
Telescopes (3-mirror heliostat design): Main - 1.61 meters - f/54 East Auxiliary - 0.91 meters - f/50 West Auxiliary - 0.91 meters - f/44