An embedded control and display system for a laser-based mid-infrared hyperspectral imager
MetadataShow full item record
Back-scatter absorption gas imaging (BAGI) is a powerful laser-based detection technique whereby the strong spectroscopic absorption features in the gaseous species of interest are exploited in order to provide an image of the otherwise invisible (to the naked eye) gas. Such a device had been under development at the University of St. Andrews for the past three years. This thesis is concerned with the work carried out in the design, construction and testing of an electronic supervisory system for such a device to both control the electro-mechanical image acquisition hardware and display the image data upon an LCD module via an on-board video driver. Two different LCD display technologies, super twisted nematic (STN) and thin film transistor (TFT), have been demonstrated and their suitability for use in this system is assessed. It was found that the refresh rate and contrast ratio of the TFT display was greatly superior to that of the STN. Frame rates in excess of 10 fps have been demonstrated with this module. In addition to the scanner, a laser management system (LMS) was designed, constructed and tested to control the laser illumination system, which is based on an intracavity optical parametric oscillator (ICOPO). This involved the development of a dual-channel PID temperature controller to stabilise various optical components located within the ICOPO illumination source, a digitally-controlled constant current source to drive the pump diode laser and a digitally controlled system for an associated Q-switch driver module. The LMS was developed as part of the miniaturisation process and resulted in one dedicated instrument replacing six individual devices required in the laboratory demonstrator. The BAGI device has now been commercialised with elements of this research program being part of the overall instrument.
Thesis, MPhil Master of Philosophy
Description of related resourcesC. R. Howle, D. J. M. Stothard, C. F. Rae, M. Ross, B. S. Truscott, C. D. Dyer and M. H. Dunn, “Active hyperspectral imaging system for the detection of liquids,” Paper 6954-XX, SPIE Chemical, Biological, Radiological, Nuclear, and Explosives (CBRNE) Sensing IX, Orlando, Florida, USA, April 2008.
D. J. M. Stothard, C. F. Rae, M. Ross and M. H. Dunn, “Mid-infrared, broadly tunable, active hyperspectral imaging system for the detection of gaseous species,” paper 6737-04, SPIE Europe conference on Security and Defence, “Electro-Optical and Infrared Systems: Technology and Applications IV” Florence, Italy, September 2007.
D. J. M. Stothard, C. F. Rae, M. Ross and M. H. Dunn, “Compact, all solid-state, high repetition rate intracavity optical parametric oscillator and its application to the spectroscopic imaging of gases and liquids,” paper CTuU3, Conference on lasers and electro-optics 2007, Baltimore, USA, May 2007.
Items in the St Andrews Research Repository are protected by copyright, with all rights reserved, unless otherwise indicated.
Showing items related by title, author, creator and subject.
Control control control : a reassessment and comparison of GenBank and chromatogram mtDNA sequence variation in Baltic grey seals (Halichoerus grypus) Fietz, Katharina; Graves, Jefferson Alden; Olsen, Morten Tange (2013-08-16) - Journal articleGenetic data can provide a powerful tool for those interested in the biology, management and conservation of wildlife, but also lead to erroneous conclusions if appropriate controls are not taken at all steps of the ...
The NAtional randomised controlled Trial of Tonsillectomy IN Adults (NATTINA) : a clinical and cost-effectiveness study: study protocol for a randomised control trial Rubie, Isabel; Haighton, Catherine; O'Hara, James; Rousseau, Nikki; Steen, Nick; Stocken, Deborah D; Sullivan, Frank; Vale, Luke; Wilkes, Scott; Wilson, Janet (2015-06-06) - Journal articleBACKGROUND: The role of tonsillectomy in the management of adult tonsillitis remains uncertain and UK regional variation in tonsillectomy rates persists. Patients, doctors and health policy makers wish to know the costs ...
Use of drug therapy in the management of symptomatic ureteric stones in hospitalized adults (SUSPEND), a multicentre, placebo-controlled, randomized trial of a calcium-channel blocker (nifedipine) and an α-blocker (tamsulosin) : study protocol for a randomized controlled trial McClinton, Sam; Starr, Kathryn; Thomas, Ruth; McLennan, Graeme; McPherson, Gladys; McDonald, Alison; Lam, Thomas; N'Dow, James; Kilonzo, Mary; Pickard, Robert; Anson, Ken; Burr, Jennifer; SUSPEND Study Group (2014-06-20) - Journal articleUrinary stone disease is common, with an estimated prevalence among the general population of 2% to 3%. Ureteric stones can cause severe pain and have a significant impact on quality of life, accounting for over 15,000 ...