This Small Business Innovation Research (SBIR) Phase II project investigates an inexpensive ultra-compact optical spectrometer based on photonic crystal arrays. Current spectrometer technology, based on diffraction gratings, has pushed the limits of current manufacturing in terms of miniaturization, and has already benefited from economies of scale. In contrast, the photonic crystal spectrometer does not use diffractive grating optics, allowing significantly decreased size and cost. The photonic crystal spectrometer is a compact spectral sensing solution suitable for applications where grating spectrometers are too bulky or expensive and dye filter arrays do not offer the needed performance. In this project, the photonic crystal spectrometer module developed in Phase I will be further developed and customized for visible and UV applications. Low-resolution implementations targeting molecular absorption/emission applications will use extensions of the technology developed in Phase I. In addition, a new technology will be developed for high-resolution implementations targeting atomic absorption/emission. The anticipated results of this project are customizable spectrometer modules suitable for applications in water, biological, and chemical analysis, as well as other applications where a moderate number of spectral signals are indicative of state.
The broader impact/commercial potential of this project includes the expansion of low-cost spectroscopic techniques to applications which have previously been infeasible due to limitations in range or resolution of commercially available technologies. The commercial potential includes new handheld and portable instruments for chemical, photometric, and biological sensing. Photonic crystal spectrometers can be integrated into compact form factors that enable in situ measurement for manufacturing process analysis and in-process feedback control. Applications include solid-state lighting characterization and testing, emissions control, portable sensing, and personal health care. The electrochemical pH and oxidation-reduction potential (ORP) measurement market, a proxy for the pH sensing market addressed by this technology, was valued at $112 million in 2006. The platform spectrometer technology has the additional potential to be applied in other areas within the water testing market, which has an aggregate value of $4 billion.
