A pavilion on the exhibit floor of the recent SPIE conference in San Diego, CA showcased consumer-level applications of photonics technology as well as several projects bringing energy-efficient lighting and cooking capabilities to the developing world. Presented under the rubric of Photonics for a Better World, the pavilion included displays of cars and solar-powered flashlights, both using LED lighting technology. The growing adoption of solid-state lighting, which has now moved well beyond commercial settings and into the home, is creating significant manufacturing challenges for makers of light-emitting diodes with consequent opportunities for photonics-based solutions. Emission wavelength and power both affect LED production yields so a variety of techniques have been developed to address them, ranging from binning (sorting) to LED designs aimed at improving the light extraction efficiency. In both cases, optical metrology can help improve the yield and product quality of high-brightness LEDs (see page 35).
Away from the consumer–but with a significant impact on them–is the seemingly relentless quest for faster communications networks. Increased capacity is the goal of next-generation coherent communications systems while preserving optical reach and agility on the existing fiber plant, but the optimization of fiber designs for these systems is only just beginning (see page 47). And at the backplane level, parallel-optics transmitters based on arrays of vertical-cavity surface-emitting lasers (VCSELs) are used to accommodate the growing data rates. At these high rates, individual monitoring of every VCSEL in the array offers systems designers new capabilities (see page 58).
Researchers worldwide continue to explore the unique ability of ultrafast pulses to alter materials without collateral damage. In Europe femtosecond pulses are being used to create microsystems, like the tiny flowers shown on our cover, by transforming the internal structure of glass–potentially creating future opportunities for system integration at the microscale (see page 13).