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Diode laser arrays, also called diode bars, are very important light sources that are generally used for pumping of other solid-state lasers and in medical and industrial applications that require high power but low intensity. Although they are very interesting from a commercial point of view, they did not find their way into many important applications because of their very low beam quality and spectral brightness.

In this work we present the results for stratospheric NO2-total column concentration retrieved by DOAS (Differential Optical Absorption Spectroscopy) performed with compact spectrographs. The behavior for three different spectrographs (MonoSpec 27, Jarrell-Ash; HR4000, Ocean Optics and Mechelle 900, Multichannel Instruments) are analyzed making one intercomparison in the facilities of the LIDAR Division of CEILAP (CITEFA - CONICET), in Villa Martelli, Argentina (34.5° S, 58.5° W, 20 m amsl). The three instruments have a similar resolution (approximately 0.1 nm) but operate with different optical configurations and have optical sensors of different characteristics; two of them have cooling capability and the other one (HR4000) operates at room temperature. The NO2 concentration was obtained from spectral results at twilight using solar noon spectra as reference. In all cases zenithal diffuse irradiance was used. The NO2 absorption cross section given by S. Voigt and J. P. Burrows (University of Bremen - Institute of Environmental Physics) corresponding to 223°K and 100 mbar is used. Results are compared with public data corresponding to ground-based device or to instruments mounted in satellites. These atmospheric soundings are of extreme importance to understand the roll that plays the stratospheric NO2 in the associated phenomena of destruction and formation of ozone in the low stratosphere at middle latitudes. Fil: Raponi, Marcelo Martín. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones Científicas y Técnicas para la Defensa. Centro de Investigación en Láseres y Aplicaciones; Argentina Fil: Wolfram, Elian Augusto. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones Científicas y Técnicas para la Defensa. Centro de Investigación en Láseres y Aplicaciones; Argentina Fil: Rinaldi, Horacio. Instituto Tecnológico de Buenos Aires; Argentina Fil: Alejandro Rosales. Universidad Nacional de la Patagonia "San Juan Bosco"; Argentina Fil: Quel, Eduardo Jaime. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones Científicas y Técnicas para la Defensa. Centro de Investigación en Láseres y Aplicaciones; Argentina Fil: Tocho, Jorge Omar. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigaciones Ópticas. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigaciones Ópticas. Universidad Nacional de La Plata. Centro de Investigaciones Ópticas; Argentina

Recent developments on micro‐structuring of ferroelectric crystals, such as LiNbO3, have opened up new possibilities for several devices in nonlinear and electro optics. In this paper, after describing the basics of LiNbO3 based integrated electro‐optic modulators, we will show how techniques such as etching, domain inversion and thin film processing can be used to realize new geometries which can take the performance to unprecedented levels. In particular we will report recent results on the use of domain inversion on a micron scale to tailor and improve the electro‐optic response of LiNbO3 waveguide modulators, showing that these applications for domain inversion techniques might be even more important and commercially valuable than those in nonlinear optics (e.g. quasi‐phase‐matched optical parametric devices). With respect to standard single‐domain structures, larger bandwidths and lower driving voltages can be obtained, thus achieving figure of merits for the electro‐optic response that are up to 50%...

An interferometry experiment is proposed, working on a Twyman‐Green optical configuration. The interferogram is acquired with a digital camera and processed. Using polarization components the interferogram is phase‐shifted and four different interferograms are acquired. The experiment is proposed as an introduction to modern phase‐shift interferometry, using concepts and laboratory equipment at the level of undergraduate optics courses.

As part of environmental studies concerning with measurements of the stratospheric ozone layer, the CEILAP developed a new Differential Absorption Lidar (DIAL) instrument. Since the early construction of the first DIAL instrument, Lidar Division has been made important financial and scientific investments to improve this initial prototype. The new version has a bigger reception system formed by 4 newtonian telescopes of 50 cm diameter each one and a higher number of detection channels: four different wavelengths are detected simultaneously and six digital channels record the Rayleigh and Raman backscattered photons emitted by an ClXe Excimer laser at 308 nm and third harmonic of Nd‐YAG laser at 355 nm. A number of different changes have been made to increase the dynamical range of this lidar: a mechanical chopper was installed together with gated photomultiplier in the high energy detection channels to avoid strong signals from lower atmospheric layers. This new version was installed inside a shelter given the possibility to make field campaigns outside CEILAP laboratories as SOLAR Campaign made in Argentine Patagonian region during 2005–2006 springs. In this paper a full description of instrument update is given. Intercomparisons with ozonesonde and satellite platform instrument are presented. The results show agreement better than 10% in 16–38 km range when same airmasses are sampled.