SCUBA (for Submillimetre Common-user Bolometer Array) is the name of two instruments (SCUBA-1 and SCUBA-2) on the James Clerk Maxwell Telescope in Hawaii.
SCUBA-1 had 91 pixels at 450 microns and 37 pixels at 850 microns, and detects thermal emission from dust. It was deployed in the 1990s and retired in 2005.
SCUBA-2 has 5120 array elements at each of the same two wavelengths, and was deployed in November 2011. With it was produced the SCUBA-2 All Sky Survey (aka SCUBA-2 Ambitions Sky Survey or SASSy), a survey of the northern sky with an angular resolution of 14 arcseconds.