Asako Baba

Design and fabrication of an apodization profile in linearly chirped fiber Bragg gratings for wideband > 35 nm and compact tunable dispersion compensator

Linearly chirped fiber Bragg gratings have been developed for a wideband and compact tunable dispersion compensator. The apodization function of positive hyperbolic-tangent profile (tanh) was designed as an optimum profile by taking a practical writing technique into consideration. This writing technique was improved by finding the optimum condition of laser power and the division number of profile. A precise tuning of dispersion compensation is achieved by controlling the temperature distribution along a fiber Bragg grating. We fabricated a compact tunable dispersion compensator with a bandwidth of >35 nm and low group-delay ripples of <10 ps.

8 X 8 digital smart pixel array

We present a digital smart pixel array, a new type of smart pixel array, for high speed parallel image processing. We have developed assembly methods for the device and fabricated 8 X 8 and 2 X 2 digital smart pixel arrays. We have also cascaded the 2 X 2 arrays, and demonstrated the functions of the device. Operation of the array can be changed by external instructions and basic operations, including data transmission between nearest neighboring pixels, were implemented. The operating speed in the cascaded system was 0.5 ms/frame.

Tunable dispersion slope compensator based on chirped FBGs with temperature distribution for 160 Gbit/s

Tunable dispersion slope compensator based on FBGs is presented, which can be tuned precisely with parabolic temperature distribution. Using this device, 160 Gbit/s signals are transmitted over 140 km within 1 dB power penalty.

Image processing on a digital smart pixel array

We have developed 8/spl times/8 digital smart pixel arrays. Each pixel has a processing element, a photodetector, a LED and diffractive optical elements. We have also implemented some image-processing algorithms on the digital smart pixel array.