Abstract

In late 1996, the Multiple Mirror Telescope will be replaced by a 6.5 m telescope with a single borosilicate honeycomb primary mirror. Earlier we showed [1] that an adaptive optics system using a low-power sodium laser guide star could provide diffraction-limited performance for infrared imaging in H and K bands, yielding the equivalent 0.05 arcsec resolution of Hubble Space Telescope optical images over most of the sky. Our approach used a continuous-wave sodium dye laser of a few watts, projected from a flat above the secondary mirror. To yield the highest efficiency and lowest emissivity, we proposed using an adaptive secondary mirror for full correction of the wavefront. In addition, the use of an infrared field star sensor to sense the global atmospheric tilt was shown to give very good sky coverage. A schematic of the system concept for the 6.5 m MMT is shown in Fig. 1.

© 1995 Optical Society of America