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Laser Induced Fluorescence (LIF) could permit fast early warning systems either for point or standoff detection if a reliable classification of warfare biological agents versus biological or non-biological fluorescing background can be achieved. In order to improve LIF discrimination capability, a new system is described in which the fluorescence pattern is enriched by the use of multiple wavelength delayed excitation while usual spectral fluorescence analysis is extended to time domain to use both aspects as criteria for classification. General considerations and guidelines for the system design are given as well as results showing good discrimination between background and simulants., QC 20141015

The results of examinations of spectroscopic properties and generation parameters of new active media, i.e., Er(3+) and Yb(3+) doped YAG crystals are given. Erbium and ytterbium doped YAG single crystals were obtained by the Czochralski method. The spectral properties and laser characteristics were investigated. Absorption spectra of Er(3+) and Yb(3+) - doped active media were measured in the spectral range 190+5000 nm at room temperature. Excitation and luminescence spectra were also recorded at room temperature with a JOBIN-YVON spectrofluorimeter using a diode laser (POLAROID 4300, 980 nm, 1 W) as an excitation source. The measurements of the lifetime of the Er(3+) ions in the upper laser level (sup 4 I sub 13/2) of the samples were made by the direct method with pulse excitation. We present also the results of investigations on spectroscopic properties and non-linear absorption effect in YAG: Co(2+) crystal - new absorber used for the systems generating giant-pulse radiation at 1.5 micrometers., Prepared in cooperation with the Polish Society for Crystal Growth, SPIE-The International Society for Optical Engineering in association with SPIE Poland Chapter; Inst. of Technical Physics, Military Univ. of Technology, Warsaw, Poland; Inst. of Electronic Materials Technology, Warsaw, Poland. Pub. in Proc. SPIE, Vol. 4412 pp406-411, 2001. This article is from ADA399287 International Conference on Solid State Crystals 2000: Growth, Characterization, and Applications of Single Crystals Held in Zakopane, Poland on 9-12 October 2000

This paper describes efforts taken in Institute of Applied Physics and Institute of Electronic Materials Technology to obtain several single crystals from borate family, namely CsLiB6O10 (CLBO) Ca4GdO(BO3)3 (GdCOB), Li2B4O7 (TBO), beta-BaB2O4 (BBO), and YAl3(BO3)4 (YAB), pure and doped with several ions. The main goal of this investigation was to develop technology of these new nonlinear optical materials to create possibility of their applications in higher harmonics generators and self-frequency doubling lasers. Depending on such properties of crystallized borate materials as incongruent melting or high temperature phase transitions, Czochralski technique or high temperature solution growth technique were used. The main aspects of crystallization of these materials as well as their optical properties are discussed., Prepared in cooperation with the Polish Society for Crystal Growth, SPIE-The International Society for Optical Engineering in association with SPIE Poland Chapter; Institute of Electronic Materials Technology, Warsaw, Poland; Institute of Optoelectronics, MUT, Kaliskiego; Institute of Microelectronics and Optoelectronics PW Koszykowa, Poland. Pub. in Proc. SPIE, Vol. 4412 pp74-80, 2001. This article is from ADA399287 International Conference on Solid State Crystals 2000: Growth, Characterization, and Applications of Single Crystals Held in Zakopane, Poland on 9-12 October 2000

Single crystals of double tungstates find applications as laser materials having very good parameters. One of the intensively investigated materials is KGd(WO4)2 doped with rare earth elements. Single crystals of KGd(WO4)2 were grown with the use of Top Seeded Solution Growth technique from K2W2O7 solvent. The crystals have low absorption losses and show high lasing efficiency. Optical investigations of as grown KGW:Nd single crystals confirmed their good optical quality and high absorption coefficient near 810 nm, what in connection with strong luminescence near 1067 nm allows fabrication of diode pumped microchip lasers working both in CW and giant pulse regime. Absorption and luminescence spectra of Nd(3+) doped KGW single crystals are presented. Laser action was obtained in form of 128.5 kHz train of 100 ns giant pulses due to YAG:Cr(4+) passive Q-switch., Prepared in cooperation with the Polish Society for Crystal Growth, SPIE-The International Society for Optical Engineering in association with SPIE Poland Chapter. Pub. in Proc. SPIE, Vol. 4412 pp69-73, 2001. This article is from ADA399287 International Conference on Solid State Crystals 2000: Growth, Characterization, and Applications of Single Crystals Held in Zakopane, Poland on 9-12 October 2000