Graduate Exam Abstract
Saurabh Gupta
M.S. Final
November 4, 2020, 2:00 pm - 3:00 pm
MS Teams
APPLICATIONS OF DIGITAL ADAPTIVE FILTERS
Abstract: Phosphorescence lifetime imaging is used on several fronts, such as, skin cancer or melanoma diagnosis, and estimation of tissue oxygenation among others. Oxygen profiling is critical for mapping brain activity, apart from its use to monitor several metabolic activities, and often employs oxygen tagging molecules/probes. In this work, we describe a novel technique to recover phosphorescence lifetime using a real-time digital adaptive filter running on a field-programmable gate array (FPGA) and conclude with an important takeaway.
In subsequent chapters, we describe our strategy to mitigate relative intensity noise (RIN) in ultrafast fiber lasers, which are an attractive alternative to bulk lasers for non-linear optical microscopy due to their compactness and low cost. The high RIN of these lasers poses a challenge for pump-probe measurements such as transient absorption and stimulated Raman scattering, along with modalities that provide label-free contrast from the vibrational and electronic structure of molecules. Later, we describe a real-time approach for RIN suppression using a digital adaptive noise canceller implemented on a FPGA. We demonstrate its application to transient absorption spectroscopy and microscopy and show compatibility with a commercial lock-in amplifier.
Adviser: Jesse Wilson
Co-Adviser: N/A
Non-ECE Member: Doug Thamm, Clinical Sciences
Member 3: Ali Pezeshki, ECE
Addional Members: N/A
Publications:
1] Real-Time Time-Resolved Optical Measurements using a Digital Adaptive Filter
2] Error estimation and enhanced stiffness sensitivity in contact resonance force microscopy with a multiple arbitrary frequency lock-in amplifier (MAFLIA)
3] Adaptive noise cancelling for transient absorption microscopy
4] RINS: A FPGA-based Real-time Relative Intensity Noise Suppressor in Pump-probe Microscopy (in review)
Program of Study:
ECE 451
ECE 561
ECE 442
GRAD 510
ECE 571
ECE 572
ECE 512
ECE 699
