laser box, projection screen
Description:
Designed
for
the
EP3
course,
this
demonstration
makes
the
lasing
threshold
apparent.
A
collimated
laser
beam
is
spread
into
spectral
components
by
a
diffration
grating,
allowing
its
power
spectrum
to
be
projected
onto
a
screen.
Spectral
narrowing
is
observed
as
the
pumping
power
is
adjusted
through
the
lasing
threshold.