- document
-
Functionalizing a Tapered Microcavity as a Gas Cell for On-Chip Mid-Infrared Absorption SpectroscopyAyerden, N.P. (author), Mandon, Julien (author), Harren, Frans J.M. (author), Wolffenbuttel, R.F. (author)Increasing demand for field instruments designed to measure gas composition has strongly promoted the development of robust, miniaturized and low-cost handheld absorption spectrometers in the mid-infrared. Efforts thus far have focused on miniaturizing individual components. However, the optical absorption path that the light beam travels...journal article 2017
- document
-
Ayerden, N.P. (author), Ghaderi, M. (author), De Graaf, G. (author), Wolffenbuttel, R.F. (author)The design, fabrication and characterization of a highly integrated optical gas sensor is presented. The gas cell takes up most of the space in a microspectrometer and is the only component that has so far not been miniaturized. Using the tapered resonator cavity of a linear variable optical filter as a gas cell enables ultimate miniaturization,...conference paper 2015
- document
-
Silva, M.F. (author), Rodrigues, J.A. (author), Oliveira, M.J. (author), Fernandes, A.R. (author), Pereira, S. (author), Costa, C.G. (author), Ghaderi, M. (author), Ayerden, P. (author), Goncalves, L.M. (author), De Graaf, G. (author), Wolffenbuttel, R.F. (author), Correia, J.H. (author)This paper presents the design, fabrication and characterization of two Fabry Perot type optical filters (415 nm and 540 nm) for enabling Narrow Band Imaging (NBI) in medical devices (MD). The two-colour illumination should satisfy a highly specific optical design, which is composed of a thin-film optical filter stack of titanium dioxide (TiO2)...journal article 2014
- document
-
Ayerden, N.P. (author), Ghaderi, M. (author), De Graaf, G. (author), Wolffenbuttel, R.F. (author)A set-up for optical gas composition measurement based on absorption spectroscopy is composed of a white light source, a gas cell and a spectrometer. The Fabry-Perot optical filter is suitable for miniaturization of this system, as it is composed of only two reflectors with a transparent layer in-between. Varying the width of this optical...journal article 2014