LaserQswitching by a PLZT shutter

The application of a polycrystalline ferroelectric ceramic Pb
1-x
La
x
(Zr
y
Ti
z
)
1-(x/4)
O
3
(called PLZT) electrooptic shutter is described for controlling the giant pulse emission of a ruby laser. The PLZT material had
y = 65
percent,
z = 35
percent, and the value of
x
was in the vicinity of 8 percent. Half-wave retardation switching was not possible with the PLZT shutter when 10-ns rise-time 70-ns-duration voltage pulses (fast
Q
switching) were applied. The increase insertion loss, due to less than half-wave retardation, resulted in laser pulsewidths that were wider and contained less energy than predicted by fast
Q
-switching theory. Since the PLZT material was damaged at relatively low power densities of between 5.6 to 8.5 MW/cm
²
, respectively, its use is restricted to
Q
-switching small output power.