38 research outputs found
Inkjet-printed vertically emitting solid-state organic lasers
In this paper, we show that Inkjet Printing can be successfully applied to
external-cavity vertically-emitting thin-film organic lasers, and can be used
to generate a diffraction-limited output beam with an output energy as high as
33.6 uJ with a slope efficiency S of 34%. Laser emission shows to be
continuously tunable from 570 to 670 nm using an intracavity polymer-based
Fabry-Perot etalon. High-optical quality films with several um thicknesses are
realized thanks to ink-jet printing. We introduce a new optical material where
EMD6415 commercial ink constitutes the optical host matrix and exhibits a
refractive index of 1.5 and an absorption coefficient of 0.66 cm-1 at 550-680
nm. Standard laser dyes like Pyromethene 597 and Rhodamine 640 are incorporated
in solution to the EMD6415 ink. Such large size " printed pixels " of 50 mm 2
present uniform and flat surfaces, with roughness measured as low as 1.5 nm in
different locations of a 50um x 50um AFM scan. Finally, as the gain capsules
fabricated by Inkjet printing are simple and do not incorporate any tuning or
cavity element, they are simple to make, have a negligible fabrication cost and
can be used as fully disposable items. This works opens the way towards the
fabrication of really low-cost tunable visible lasers with an affordable
technology that has the potential to be widely disseminated
Direct imprinting of organic-inorganic hybrid materials into high aspect ratio sub-100nm structures
The challenging fabrication of sub-100-nm structures with high aspect ratio by UV-nanoimprint lithography (NIL) is addressed in this work. Thermal shrinkage is induced by cooling the structures below room temperature to avoid the issues commonly arising during the release of the polymeric nanostructures from the master. The UV-NIL has been performed to obtain OrmoComp® nanostructures using OrmoStamp® working stamps copied from Si masters. Nanoridges and nanopillars with 45nm width and 380nm thickness have been fabricated with a corresponding aspect ratio of 8.5. This is, to the best of our knowledge, the highest aspect ratio achieved using organic-inorganic hybrid materials at the sub-100-nm scale
Mechanically tuneable microoptical structure based on PDMS
A system of two solid microlenses with uncoupled optical properties is presented. This structure has been designed in order to have one lens as a reference, while the other one can be mechanically tuneable. The reference lens presents a diameter of 2 mu m and it is placed in the optical axis of the mechanically tuneable lens, which has a diameter of 10 mu m. The proposed microoptical structure has been fabricated in poly(dimethilsiloxane) (PDMS) merging deep reactive ion etching, SU-8 and soft lithography, with a low-cost (mass-production), simple and highly repetitive technology. This device was numerically simulated prior to its fabrication, to optimize its design and improve its behaviour. In addition, an optical characterization of the fabricated devices was carried out. Both simulation and experimental results shows a good agreement, under mechanical actuation behaviour of the reference lens is invariable, while the tuneable lens become an elliptic lens and the interval of Sturm can be observed. These results provide a proof of concept of the proposed devices and validate both the design and the fabrication technology. (C) 2010 Elsevier B.V. All rights reserved
Direct imprinting of organic-inorganic hybrid materials into high aspect ratio sub-100 nm structures
The challenging fabrication of sub-100-nm structures with high aspect ratio by UV-nanoimprint lithography (NIL) is addressed in this work. Thermal shrinkage is induced by cooling the structures below room temperature to avoid the issues commonly arising during the release of the polymeric nanostructures from the master. The UV-NIL has been performed to obtain OrmoComp(A (R)) nanostructures using OrmoStamp(A (R)) working stamps copied from Si masters. Nanoridges and nanopillars with 45 nm width and 380 nm thickness have been fabricated with a corresponding aspect ratio of 8.5. This is, to the best of our knowledge, the highest aspect ratio achieved using organic-inorganic hybrid materials at the sub-100-nm scale
Polymeric MOEMS variable optical attenuator
In this letter, we take advantage of the high coefficient of thermal expansion (CTE) of a chemically amplified, epoxy-based negative polymer (SU-8) to define a low-power consumption polymeric variable optical attenuator that combines the working principles of microoptoelectromechanical systems and photonic light-wave circuits. The SU-8 symmetric structure comprises a seismic mass and four mechanical beams. Three multimode waveguides are defined on this structure: two of them are located on the frame and the third one in the middle of the seismic mass. Aluminum is used as a heater electrode extending over two of the mechanical beams and part of the seismic mass. When a dc voltage is applied, the mechanical beams bend, resulting in a misalignment between the waveguides. Experimental results have shown a power consumption of 12 mW at 20 dB with a working wavelength of 633 nm emitted from a light-emitting diode
La Lanterne : journal politique quotidien
03 août 18951895/08/03 (N929,A12)