|
A
continuous
wave (CW)
is an
electromagnetic
wave of
constant
amplitude
and
frequency;
and in
mathematical
analysis,
of
infinite
duration.
Continuous
wave is
also the
name
given to
an early
method
of radio
transmission,
in which
a
carrier
wave is
switched
on and
off.
Information
is
carried
in the
rhythm
and
spacing
with
which
the
signal
is sent.
CW is
thus is
a form
of
on-off
keying (OOK).
The
output
of a
laser
which is
operated
in a
continuous
rather
than a
pulsed
mode.
For
purposes
of
safety
evaluation,
a laser
operating
with a
continuous
output
for a
period >
0.25 s
is
regarded
as a cw
laser. |
