VI Systems GmbH of Berlin has acquired an exclusive silicon photonics patent license for applications in sensing, data communications and illumination using vertical-cavity LED structures. The patent addresses the ability to fabricate surface-emitting lasers and LEDs in any materials system by attaching a dielectric cavity layer, confined by multilayer dielectric distributed Bragg reflectors on both sides of the gain medium. The technique enables light trapping and amplification, even if the cavity layer itself remains passive. It allows integration of the device with photonic crystals, waveguides and subwavelength gratings, and offers an option of high-temperature wavelength stability for uncooled dense-wavelength division multiplexing applications. AFL of Spartanburg, N.C., has received a patent for the development of optical time-domain reflectometers (OTDRs) to detect and test fiber signals. In the patented technology, multiple wavelength-specific test signal generators and detector channels are combined on a single OTDR test port. The approach enables users to determine whether a fiber is live or dark, to measure the power level of any signals present on the fiber and to apply test signals (including noninterfering signals) on dark and live fibers, all without having to swap test ports or equipment.