Dissertation/ Thesis
Radiometric analysis of LEDs and the use of rapidly pulsed infrared LEDs for portable sensing of gases
| العنوان: | Radiometric analysis of LEDs and the use of rapidly pulsed infrared LEDs for portable sensing of gases |
|---|---|
| المؤلفون: | Noori, A |
| سنة النشر: | 2018 |
| المجموعة: | University of Tasmania: UTas ePrints |
| مصطلحات موضوعية: | Light Emitting Diodes (LEDs), optical sensing, radiometric power output, rapid microsecond pulsing, redpitaya, microcontroller with FPGA, wireless data transfer and on-the-fly data processing, real time gas monitoring |
| الوصف: | This thesis focuses on the radiometric analysis of commercial light emitting diodes (LEDs) and investigation and development of an infrared (IR) LED based optical sensing system for continuous monitoring of methane gas with wireless, on-the-fly and flexible data processing capabilities in indoor and outdoor environments. The areas of analytical use of LEDs as well as of gas monitoring with IR LEDs covered in the scientific literature are reviewed in Chapter 1. The first experimental section of this thesis (Chapter 2) focuses on radiometric analysis of LEDs. LEDs have been established as light sources in countless areas where they offer a better alternative to traditional light sources in terms of low-cost, small size and robustness supporting portability, performance parameters such as low noise and wide applicability. Lack of rapid, facile and accurate radiometric analysis of LEDs is a major limiting factor which constrains their purposeful use in analytical chemistry. A holistic radiometric analysis of LEDs in terms of absolute emission spectra analyses, radiometric power output, irradiances, radiant efficiencies as well as uncertainties are invaluable to analytical chemists as such analysis has the capability to justify the purposes of LEDs as light sources in analytical chemistry. We demonstrate and cross-validate a rapid, facile, accurate and low-cost radiometric analysis of LEDs with directional light output using a large active area silicon photodiode in a simple optical design with the LED light source in proximity, without the need for a calibrated light source. The obtained radiometric data for a wide range of 21 commercial LEDs in UV, visible and near-infrared (NIR) spectral range (255-950 nm) agree very well with two completely independent approaches: chemical actinometric and spectrophotometric methods. At first, an excellent agreement was achieved with accuracy within 5% for radiometric power output (mW) measured using chemical actinometric methods and further, the accuracy of irradiance (mW/cm2) ... |
| نوع الوثيقة: | thesis |
| وصف الملف: | application/pdf |
| اللغة: | English |
| Relation: | https://eprints.utas.edu.au/28545/1/Noori_whole_thesis_ex_pub_mat.pdf; https://eprints.utas.edu.au/28545/2/Noori_whole_thesis.pdf; Noori, A orcid:0000-0002-8231-5537 2018 , 'Radiometric analysis of LEDs and the use of rapidly pulsed infrared LEDs for portable sensing of gases', PhD thesis, University of Tasmania. |
| الاتاحة: | https://eprints.utas.edu.au/28545/ https://eprints.utas.edu.au/28545/1/Noori_whole_thesis_ex_pub_mat.pdf https://eprints.utas.edu.au/28545/2/Noori_whole_thesis.pdf |
| رقم الانضمام: | edsbas.F5C1284D |
| قاعدة البيانات: | BASE |
| الوصف غير متاح. |