Passively Q-switched Yb : YAG laser with Cr4+: YAG as the saturable absorber

By using a continuous-wave Ti:sapphire laser as a pumping source, we demonstrated a passively Q-switched Yb:YAG laser at room temperature with Cr4+:YAG as the saturable absorber. We achieved an average output power of as much as 55 mW at 1.03 mum with a pulse width (FWHM) as short as 350 ns. The initial transmission of the Cr4+:YAG has an effect on the pulse duration (FWHM) and the repetition rate of the Yb:YAG passively Q-switched laser. The Yb:YAG crystal can be a most promising passively Q-switched laser crystal for compact, efficient, solid-state lasers. (C) 2001 Optical Society of America.

Caso práctico de auditoría de cuentas de la empresa SOGE Absorber, SA

[ES] Este documento recoge los procedimientos llevados a cabo y las conclusiones a las que ha dado lugar el trabajo de auditoría realizado a la sociedad SOGE Absorber SA, dedicada a la producción y distribución de amortiguadores, resortes y otros componentes de la industria del automóvil tanto para vehículos turísticos como industriales. En el presente documento se procederá a realizar un estudio del entorno y características de la entidad con la finalidad de evaluar el nivel de riesgo de auditoría y conocer mejor la situación económico-financiera. El objetivo final de la auditoría realizada será aumentar la confianza de los usuarios en los EEFF, para lo que se emitirá, por parte del auditor, una opinión sobre si los estados financieros han sido preparados, en todos los aspectos significativos, de conformidad con el marco de información financiera que le es aplicable. Como base para dicha opinión, el marco normativo de auditoría requiere que el auditor obtenga una seguridad razonable de que dichos estados financieros en su conjunto están libres de incorrección material,debida a fraude o error. En todo caso, la auditoría de cuentas de la empresa SOGE Absorber SA que se presenta en este proyecto toma como base las Normas Técnicas de Auditoría (NTA) vigentes a fecha 1 de enero de 2014, constituidas por las Normas Internacionales de Auditoría adoptadas en España (NIA-ES). El Trabajo Fin de Grado (TFG) recoge algunos de los aspectos más significativos detectados en la auditoría de Cuentas del ejercicio cerrado a 31 de diciembre de 2014.

Diode-pumped passively q-switched Nd : YAG ceramic laser with a Cr4+: YAG crystal-satiable absorber

Transparent polycrystalline Nd:YAG ceramics were fabricated by solid-state reactive sintering a mixture of commercial Al2O3,Y2O3, and Nd2O3 powders. The powders were mixed in ethanol and doped with 0.5 wt% tetraethoxysilane, dried, and pressed. Pressed samples were sintered at 1750 degrees C in vacuum. Transparent fully dense samples with average grain sizes of 10 mu m were obtained. The 1 at.% Nd:YAG ceramic was used to research passively Q-switched laser output with a Cr4+:YAG crystal as a saturable absorber. An average output power of 94 mW with a pulse width of 50 ns was obtained when the incident pump power was 750 mW. The slope efficiency was 13%. The pulse energy is 5 mu J, and the peak power is about 100 W.

Passively Q-switched Yb3+ laser with Yb3+-doped CaF2 crystal as saturable absorber

Passive Q-switching of a diode-pumped Yb:LYSO laser at 1060 nm with a Yb3+ ions-doped CaF2 crystal without the excited-state absorption (ESA) was demonstrated. An average output power of 174 mW with pulse duration of 5.6 mu s and repetition rate of 27 kHz have been obtained under the unoptimized conditions. And the Q-switching conversion efficiency was as high as 51.7%. (c) 2007 Optical Society of America.

Measurements of light scattering from glass substrates by total integrated scattering

A total integrated scattering (TIS) measurement was performed to investigate the surface and volume scattering of K9 glass substrates with low reflectance. Ag layers with thicknesses of 60 nm were deposited on the front and back surfaces of the K9 glass substrates by the magnetron sputtering technique. Surface scattering of the K9 glass substrate was obtained by the TIS measurement of the Ag layers on the assumption that the Ag layers and the K9 substrate had the same surface profile. Volume scattering of the substrates was deduced by subtracting the front and back surface scattering from the total scattering of the substrates. (c) 2005 Optical Society of America.