Abstract: A transducer plate having at least two mounting zones separated by a transverse groove of a depth greater than the desired thickness of the transducer plate obtained after polishing the mounted transducer plate, and a method for mounting the transducer plate to an optical medium to form an acousto-optic device are disclosed.

Abstract: An improved infrared acousto-optic tunable filter is provided by an acousto-optic birefringent crystal having polished, uncoated input and output faces normal to the radiation incident-on or diffracted-by the crystal, respectively, and wherein crystallographic axis is oriented at about 21 degrees to the incident infrared radiation, rf transducer means coupled to the crystal for tuning or selecting a narrow bandwidth infrared wavelength of interest, and input and output wire grid polarizer are aligned with the crystal. The input wire grid polarizer is aligned to polarize the input infrared radiation in the same plane as the plane of the b-c crystalline axes of the crystal. The output wire grid polarizer is disposed with the parallel conductors aligned transversely to the conductors of the input polarizer, so that only the selected or tuned bandwidth of interest is transmitted through the output polarizer.

Abstract: An automated acousto-optic tunable filter infrared analyzer system useable in a variety of industrial and commercial control applications. The system relies upon a narrow band pass tunable acousto-optic filter which is selectively tuned by predetermined rf frequency signals to selectively transmit the narrow band pass of interest which corresponds to a specific molecular species for identification and analysis. The system includes a microcomputer and associated memory function to measure and compare detected signals from an infrared detector which converts the filtered infrared signal to an electrical signal. The memory provides control signals for the computer and for controlling the sequence and frequency of rf energy applied to tune the filter. In this way, the near to mid range infrared can be analyzed for absorption bands corresponding to predetermined molecular species such as combustion product gases, and a feedback signal generated to control the combustion process.

Abstract: A broadband antireflection multilayer coating for infrared transmissive materials comprises a first thin film layer selected from the group consisting of zinc-selenide and zinc-sulfide, a second thin film layer selected from the group consisting of lead-fluoride and aluminum oxide and a third thin film layer selected from the group consisting of magnesium-fluoride, barium-fluoride and calcium-fluoride. This antireflection coating is particularly useful with acousto-optic tunable filter systems, wire grid polarizers and infrared frequency doublers.

Abstract: An improved self Q-switching Nd--UO.sub.2 -glass laser is provided in which a diffusing medium is included, either within the laser rod or externally thereof to increase the effective volume of the laser rod. Various diffusing means are disclosed including optical inhomogeneities, diffusion coatings, and curvilinear resonators.