Functional inorganic thin films
Hyperspectral imaging combines two-dimensional imaging and spectroscopy. A hyperspectral image therefore includes a third dimension, which represents the optical spectrum in each pixel. One approach to realize a hyperspectral imaging system is to combine a broadband camera sensor with a tunable optical bandpass filter.
At NanoSYD, we are developing optical filters for thermal hyperspectral imaging applications based on a Fabry Perot interferometer principle. Two partially transmitting mirrors are realized as multilayer stacks of high and low refractive index materials. The mirrors form an optical cavity with a width carefully controlled by piezo elements. These enable the scanning of the center wavelength of the optical filter which, combined with a broadband camera sensor, realizes a hyperspectral imaging system. The thin films are deposited by various physical vapor deposition techniques and are studied by a range of experimental techniques incl. ellipsometry, SEM, energy-dispersive X-ray spectroscopy, FTIR, atomic force microscopy and more.
Moreover, we also have activities relating to the development of advanced materials for high-temperature strain gauges. The thin-film materials are deposited by a reactive sputtering process, which can enable the composition and the morphology of the deposited films to be varied over a wide range. The thin films are studied by different experimental techniques incl. ellipsometry, energy-dispersive X-ray spectroscopy, atomic force microscopy, and electrical and electromechanical measurements.
NanoSYD members working within this research area
Jakob Kjelstrup-Hansen, Associate Professor
Mads Nibe Larsen, Industrial PhD student
Funded projects
Methodologies for Hyperspectral Thermal Imaging. Innovation Fund Denmark, Industrial PhD project in collaboration with Newtec Engineering A/S, 2018-2021.
Thin film strain gauges for high temperature applications. Innovation Fund Denmark, Industrial postdoc project in collaboration with Danfoss A/S, 2013-2015.
Selected publications
Acquisition and Analysis of Hyperspectral Thermal Images for Sample Segregation, A. C. L. Jørgensen, J. Kjelstrup-Hansen, B. B. E. Jensen, V. Petrunin, S. F. Fink and B. Jørgensen, Applied Spectroscopy, in print, DOI: https://doi.org/10.1177/0003702820972382
Three-point bending setup for piezoresistive gauge factor measurement of thin-film samples at high temperatures, N. D. Madsen and J. Kjelstrup-Hansen, Review of Scientific Instruments. 88, 015001 (2017)
Titanium Nitride as a Strain Gauge Material, N. D. Madsen, M. Hausladen, S. Chiriaev, P. Johannesen, Z. E. Fabrim, P. F. P. Fichtner and Kjelstrup-Hansen, J., I E E E Journal of Microelectromechanical Systems, 25, 4, 683 (2016)