Abstract: A two-cell Raman converter for generating a relatively large number of Stokes shifted waves from an input laser pump beam. A first lens focuses the pump beam into the first cell, whose output is recollimated and focused by second and third lenses into the second cell. The second cell output is recollimated by a recollimating lens to provide the final output. Each Raman cell employs stimuated rotational Raman scattering and Raman media at low pressures optimized to achieve maximum conversion into Stokes lines.

Abstract: A transmitter for producing an energy beam which has encoded thereon as a polarization state of the energy, angular position along a selected one of a plurality of dimensions across the beam. The transmitter comprises a laser unit for transmitting energy through a plurality of switchable modulators with each of said modulators comprising an electro-optical device, such as a 180.degree. retarder or a 90.degree. rotator, coupled between a pair of birefringent wedges. The wedges are configured such that when the associated electro-optical device is not energized the birefringence of the wedges cancel. When energized, the electro-optical device translates the polarization state of the energy passing therethrough such that the birefringence of the wedges add so as to cause a variation in the polarization across the beam. The spatial orientation of the two wedges in a given modulator determines the dimension across the beam encoded thereby.

Abstract: A system for providing signals which are indicative of a target's position along at least one dimension across an electromagnetic energy beam. The system comprises a transmitter for transmitting energy which is encoded such that the polarization state of the energy varies across the beam, and a receiver which responds to the polarization of the received energy to provide signals indicative of the relative position of the target within the beam.

Abstract: A passive laser Q-switch cell is disclosed wherein a chamber containing a liquid Q-switching material has an extent along the laser beam path not greater than approximately 0.25 mm. When the laser beam has a frequency of approximately 1.06 .mu.m, the Q-switching material may consist of a substantially saturated solution of the dye complex bis(4-dimethylaminodithiobenzil)nickel in toluene.

Abstract: A coating consisting of polycrystalline Sm.sub.2 O.sub.3 powder dispersed in a Na.sub.2 SiO.sub.3 or K.sub.2 SiO.sub.3 binder may be provided on either the inner or outer lateral surface of a substantially tubular pumping cavity housing member for a Nd:YAG laser. The coating is absorptive of radiation at the lasing wavelength of about 1.06 .mu.m and has a thickness sufficient to provide a high diffuse reflectivity for pumping radiation.