We proposed a novel optical power measurement scheme, which significantly improved resolution (OPR) by implementing an amplified-spontaneous-emission feedback circuit (ASEFC) ahead of conventional meter. The scheme was named “ASEFC scheme.” ASEFC operates in regions near the lasing threshold. OPR characteristics were clarified experimentally. demonstrated OPRs loss component. less than 0.00014 ...

A technique to suppress optical nonlinearities is demonstrated using adaptive optical domain post distortion. The concept, rooted in electrical domain linearization, mitigates optical nonlinearities by generating sidebands that are equal but opposite in phase from the unwanted components. We model and experimentally demonstrate >20 dB extinction in four wave mixing by an adaptive phase controll...

We report on the use of a high-speed wavelength division multiplexing (WDM) technique for multiplexing Fiber Bragg Grating (FBG) sensors applied to structural Vibration Control for the measurement of strain, permitting many sensing devices along a single optical fiber at different locations collecting samples at 5000 Hz with microstrain resolution. In this demonstration, a cantilevered flexible...

Recent realizations of single-atom trapping and tracking in cavity QED open the door for feedback schemes which actively stabilize the motion of a single atom in real time. We present feedback algorithms for cooling the radial component of motion for a single atom trapped by strong coupling to single-photon fields in an optical cavity. Performance of various algorithms is studied through simula...

We investigate experimentally and theoretically the dynamics of a semiconductor laser subject to filtered optical feedback. Depending on the feedback strength we find dynamical regimes with different dependence on the feedback phase. In particular, the influence of the feedback phase on cw emission and on frequency oscillations is characterized experimentally. We also measure the dependence of ...

Semantic web technologies have been applied to many aspects of learning content authoring including semantic annotation, semantic search, dynamic assembly, and personalization of learning content. At the same time, social networking services have started to play an important role in the authoring process by supporting authors' collaborative activities. Whether semantic web technologies and soci...

The filling of printed forms has always been an issue for the visually impaired. Though optical character recognition technology has helped many blind people to ‘read’ the world, there is not a single device that allows them to fill out apaper-based form without a human assistant. The task of filling forms is however an essential part of their daily lives, for example, for access to social secu...

In this paper, we consider the track-following control problem in the optical data storage systems in the presence of the eccentricity. The eccentricity results in the radial deviation of the objective lens so that it degrades the reliability of the data decoding system. To cope with the eccentricity, an adaptive disturbance compensation technique is newly proposed in the time domain based on a...

A combined photon scanning tunneling and shear-force microscope has been developed to investigate the optical field distribution in a planar waveguide splitter and a multibranch mode mixer. The optical intensity distribution just above the surface of a planar waveguide is mapped with subwavelength resolution by a tapered optical fiber that probes the evanescent field. Simultaneously, the topogr...