  VERITAS is a new atmospheric Cherenkov imaging telescope array to detect very
high energy gamma rays above 100 GeV. The array is located in southern Arizona,
USA, at an altitude of 1268m above sea level. The array consists of four 12-m
telescopes of Davies-Cotton design and structurally resembling the Whipple 10-m
telescope. The four focal plane instruments are equipped with high-resolution
(499 pixels) fast photo-multiplier-tube (PMT) cameras covering a 3.5 degree
field of view with 0.15 degree pixel separation. Light concentrators reduce the
dead-space between PMTs to 25% and shield the PMTs from ambient light. The PMTs
are connected to high-speed preamplifiers allowing operation at modest anode
current and giving good single photoelectron peaks in situ. Electronics in the
focus box provides real-time monitoring of the anode currents for each pixel
and ambient environmental conditions. A charge injection subsystem installed in
the focus box allows daytime testing of the trigger and data acquisition system
by injecting pulses of variable amplitude and length directly into the
photomultiplier preamplifiers. A brief description of the full VERITAS focal
plane instrument is given in this paper.
