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Optical Society of Northern California Meeting

Optical Society of Northern California

24 May 2012
8:00-10:00pm; optional dinner with speaker at 6:30pm (RSVP ncal.osa@gmail.com)
George E. Pake Auditorium, PARC, map/ directions



The Northern California Local Section of Optical Society of American (NCal OSA) has the aim and purpose to promote local, interdiscipline, and multinational interactions between optics professionals in Northern California, by tapping into the strong and diversified industrial and academic resources in Silicon Valley and Bay Area. To support this purpose NCal OSA will reach out and work with other local OSA sections, OSA Student Chapters, optics related professional organizations like SPIE and IEEE, and other professional organizations in the mechanical, electronic, biological, and chemistry areas. We encourage those from other areas to attend talks and interact through the website. We will also have talks where we bring in experts from other disciplines who use optics to provide their unique perspective.


Dr. Kiesel is conducting research in the areas of compact optical sensing systems, ultra sensitive light detection, and nitride based light emitters. Leading the optical detection group at PARC, Peter's current research and development activities include compact on-chip optical detection systems targeting bio-technological and medical applications. Key technologies that he has developed over the last 5 years include: Micro-fluidic-based optical detection platform for on-the-flow analyte characterization; Spatially modulated excitation and emission technique for analyte detection with improved signal-to-noise discrimination which enables point-of-care flow cytometers; Low-cost interrogation unit for wavelength-encoded optical sensors; Improved light/target interaction by guiding light in the fluid containing the analyte; Cavity-enhanced sensing, a method enabling on-the-flow absorption and refractive index measurements in a microfluidic device; Chip-size spectrometer which enables fluorescence spectroscopy on a chip; and Detection of individual bacteria based on native fluorescence. Dr. Kiesel is author or coauthor of more than 240 scientific publications including 90 refereed journal articles, 53 issued patents, 22 patent applications and 3 book chapters. He has organized many international workshops and conferences and has been the principal investigator on more than 12 research projects covering a large variety of sensing systems and optoelectronic devices (e.g., pathogen detection in water, micro-fluidic flow cytometer, bio-detection based on native fluorescence spectroscopy, highly efficient light emitters, light modulators, sensitive photo detectors, opto-optical switches, and polarization coded logic elements).

Opto-fluidic Detection System Enabling Sophisticated Point-of-care Diagnostics

The strategic landscape for biological and biomedical testing is undergoing a truly disruptive transformation. Today the majority of tests are performed at major, centralized clinical laboratories since compact, robust, and inexpensive instruments for point of care (POC) testing are not available. The principal drivers for POC testing are reducing costs, obtaining timely test results, lowering mortality rates, and reducing morbidity. We have demonstrated and prototyped a new optical detection approach that delivers high signal-to-noise discrimination – without complex optics, expensive detectors or bulky excitation sources. It therefore enables a truly compact and low-cost microfluidic-based instrument that can be used for diagnostics on whole blood or other complex fluids. The enabling technique is termed “spatially modulated emission” and generates a time-dependent signal as a continuously fluorescing bio-particle traverses a predefined pattern for optical transmission. Correlating the detected signal with the known pattern achieves high discrimination of the particle signal from background noise. The detection technique has been evaluated with measurements of CD4+ lymphocytes in human blood, which is required for initiation and monitoring the treatment of HIV-infected patients. The technique has been benchmarked against a commercial instrument and excellent agreement for both absolute CD4 and percentage CD4 has been demonstrated. More recent experiments showed that our detection platform can address a large variety of diagnostic needs including multiplexed bead-based assays (ELISA on-the-flow) and identification and enumeration of pathogens (e.g., Giardia, Cryptosporidium and E.Coli) in fluids.