A higher intensity eye safe laser is provided for long range target designation
or illumination as well as long range eye safe communications by providing a single
beam line combination of an optical parametric oscillator and optical parametric
amplifier which are used to double the output of the optical parametric oscillator
while limiting beam spread to less than 1.2 milliradians assuming a 20 mm clear
aperture. The OPO/OPA combination requires no conditioning, isolation or synchronization
optics and provides a factor of two improvements in beam quality as compared to
an equivalent optical parametric oscillator, with the subject system providing
a compact robust configuration. The high conversion is provided by the use of a
simple optical parametric oscillator seeding an optical parametric amplifier without
double passing the pump pulse in the optical parametric oscillator. Low beam divergence
operation is provided with minimum optics in a compact space with the optical parametric
oscillator operating at a reduced signal intercavity flux which provides increased
damaged threshold margins.
