Monoblock laser for a low-cost, eyesafe, microlaser range finder

A small, lightweight, low-cost prototype laser has been developed for use in a microlaser range finder (mu LRF). The laser design is based on a flash-lamp-pumped, Nd:YAG laser with a Cr4+ passive Q switch. The design incorporates a monolithic potassium titanyl arsenide (KTA) optical parametric oscillator (OPO) in an intracavity configuration, producing output at 1.54 mu m Precisely cut, properly coated crystals make up the laser resonator, reducing the number of components and enabling laser oscillation with the simplest of alignment fixtures. The 1.54-mu m laser cavity consists of only four rectangular-shaped crystals: a Nd:YAG laser rod, a Nd:YAG endcap, a Cr4+ Q switch, and a KTA OPO. Along with a ceramic laser pallet and a flash lamp, these six components make up a prototype monoblock (essentially a one-piece) laser transmitter. Several of these simple prototypes have been built and tested, giving a nominal output of >3.0 mJ at 1.54 mu m with a 27-ns pulse width. The transmitter was incorporated into a breadboard laser range finder, and successful ranging operations were performed to targets at ranges in excess of 3 km. (C) 2000 Optical Society of America OCIS codes: 140.0140, 140.3530, 140.3540, 140.3580, 280.3400.