We propose and demonstrate wavelength-selectable filters available for 32 WDM channels using a micro-mechanically movable mechanism with miniaturized voice-coil motors (VCMs). A simple straight geometry with a staggered configuration is used to densely pack 32 in/out moving elements into a small space of 452411 mm. The elements are precisely arranged along a collimated beam between fiber facets to provide flat-top passbands centered at ITU-T grids while maintaining small total insertion losses of less than 2.5 dB for all elements. The driving condition of the VCMs is also optimized for quick dynamic response with typical settling time of less than 10 ms. A repetition test 106 repetitions per element showed good wavelength reproducibility to an accuracy of below 0.1 nm, indicating the switches are feasible for practical system equipped with reconfigurable functionality for the next generation of optical networks.

The light output of a injection laser in a short (several µm) external cavity has been investigated both experimentally and theoretically. The amplitude modulation ratio of the light output signal reaches maximum where the drive current is below the threshold lasing current. An antireflection coated (ARC) laser diode is useful in increasing the light signal.

The Dynamic Readout performance of a micro-optical head, consisting of a semiconductor laser on a flying slider and a glass substrate disk medium has been examined. An antireflection coated (ARC) laser diode, whose reflectivity facing a medium, is less than 5%, is useful in decreasing signal amplitude fluctuation due to the head-to-medium spacing.

This paper considers a more generalized capacitor that can decrease its width using its own electrical force. We consider a model in which the capacitor with plate distance d is coupled with repulsive mechatronical potential energy, which is proportional to 1/dn. In the conventional case, n is considered to be approximately very large. In our capacitor model, there is a stable point between attractive electrical force and repulsive mechatronical force. In this system, electrostatic energy is equal to the sum of mechatronical potential energy and energy dissipation. Moreover, the mechatronical potential energy is 1/n times smaller than the electrostatic energy. All energies, including the electrostatic energy, potential energy, and energy dissipation, are proportional not to ordinary value V2, but to V2/(n-1)+2, where V is the power supply voltage. This means the voltage dependence of energy is unusual. It is strongly dependent on the capacitor matter, i.e., on the characteristics of the mechatronical system. In addition, the energy dissipation of the system can be reduced to zero using the adiabatic charging process.

We propose a mechanically tunable passively mode-locked semiconductor laser with a high repetition rate using a simple configuration with a moving mirror located very close to a laser facet. This scheme is demonstrated for the first time by a novel micromechanical laser consisting of an InGaAsP/InP multisegment laser with a monolithic moving micro-mirror driven by an electrostatic comb structure. The main advantage of this laser is the capability of generating high-quality mode-locked pulses stabilized by a phase-locked loop (PLL) with low residual phase noise in a wide repetition-rate tuning range. This paper describes the basic concept and tuning performances utilizing the micromechanical passively mode-locked laser in 22-GHz fundamental mode-locking and in its second-harmonic mode-locking.

Phase change recording with an optically switched laser (OSL) head is realised for the first time. This head consists of a 1.3µm wavelength laser diode monolithically integrated with a photodetector (LD-PD) and a flying slider. The lensless OSL head has a minimum power of 18 mW (1 MHz) for writing information on a 1200 rpm, 130 mm diameter, SbTe based alloy disk. The bit shape and crystalized level are uniform and the readout signals are of high quality.