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Optical Wireless Power Transmission (OWPT) is one of the technologies of wireless energy transfer. OWPT uses optical light source as an energy emitter, and solar panel as an energy detector. With current trends of availability of large laser power source at lower prices and sophisticated image recognition technologies, OWPT increases its attention. In order to obtain high energy transfer efficiency in OWPT, precise control of laser illuminating position is required. We apply co-axially aligned optical system of imaging function and laser beam steering function to satisfy the requirement. At the presentation, we will introduce our approach of OWPT.

The possibility of an areal density over 50 Gbit/in2 was examined in near-field phase-change recording. The disk structure was optimized to maximize readout signals under the land-and-groove recording condition at a tracking pitch of 160 nm. We also evaluated the signal crosstalk from adjacent tracks. Eye diagrams of 50.4 Gbit/in2 areal density were demonstrated using 1.5 NA optics and a GaN laser diode. The track pitch and linear bit density are 160 nm and 80 nm/bit, respectively. The transmission electron microscope (TEM) micrograph of recorded amorphous marks at an areal density of 50.4 Gbit/in2 is also presented.

An optoelectronic CMOS memory technology is proposed where photon induced floating body effect stimulates switching and hysteresis in the transistor. The floating body effect is induced by exceedingly few carriers generated by two photon absorption. In this paper we present the structure of proposing device and numerically validated the device by Atlas device simulator from SILVACO Corporation.

A novel approach to three-dimensionally (3-D) integrate nanophotonic and electronic devices in silicon is described. The method is based on the SIMOX (Separation by Implantation of OXygen) process, to realize three-dimensionally (3-D) integrated devices in a monolithic fashion. In this approach, photonic and electronic devices are realized on vertically stacked layers of silicon, separated from each other by a dielectric layer of silicon dioxide formed through the process of oxygen implantation. Opto-electronic integration is demonstrated by realizing photonic circuits in a subterranean silicon layer and Metal-Oxide-Semiconductor (MOS) transistors on a surface layer of silicon. Optical and electronic functionalities are thus separated into two different layers of silicon, paving the way towards dense three-dimensional opto-electronic integration. This has the significant advantage that photonic devices do not consume any of the expensive silicon real estate required for CMOS circuitry. The versatility of the technique of SIMOX 3-D sculpting in obtaining complex optical circuitry is also demonstrated by synthesizing a cascaded microdisk structure that may be utilized to tailor the passband characteristics of optical filters.

We proposed the phase-profile modulating device with microdots on the electrode of LC panel. The phase modulation profile corresponding with the profile of density modulated microdots on the electrode of the device, was demonstrated.

We propose multi-layer near-field recording with using inner focus mode. The restricted conditions for multi-layer near-field recording are discussed from the viewpoint of both media structure and optical setup. One solution is presented for dual layer recording with a numerical aperture (NA) of 1.5 and a wavelength of 405 nm as a light source of GaN laser diode.In the proposed layer structure, a Nb2O5 material has been adopted as the intermediate layer because of its high refractive index, n = 2.4, in order to prevent the decrease of beam propagation that corresponds to NA>1. Almost the same signal characteristics can be obtained from both recording layers at the air gap of 40 nm. The adjustment of focusing position and the compensation of spherical aberrations have been implemented by the combination of an expander lens unit and a liquid crystal (LC) panel in the optical setup.

We demonstrated near-field recording with the combination of a GaN laser diode and a 1.5 NA objective lens. The realized linear bit density was less than 90 nm (corresponding to the areal recording density over 40 Gbit/in/sup 2/) regardless of using a small 1.0 mm-diameter super-hemispherical solid immersion lens (SIL). Further improvement of a near-field phase-change optical disk will enable a linear bit density of 80 nm or less. In this talk we shall also report the fabrication process of the plateau, and of the electrode on the SIL.

Recently, solid immersion lenses (SILs) have yielded a great interest in near-field optical data storage. However, convincing data on areal recording density have yet to be reported. The difficulty is attributed to the fact that an air-bearing slider needs to be kept optically contacted and also that a tiny SIL is vulnerable to aberrations caused by an air gap between a lens and a disk. The air-bearing system cannot easily achieve the condition above because its linear velocity changes the air gap. We have developed a new SIL device mounted on an actuator, which allows the air gap to be varied arbitrarily and enables optical contact independent of disk rotation. The obtained eyepattern of (l,7)-coded data on a phase-change disk demonstrates near-field recording over 1.2- numerical-aperture (NA).

We have fabricated a plasma-etched lens about three times larger than our previous design by using a novel selectivity control technique during transfer processes, and performed phase-change optical recording for the digital-video-recording (DVR)-blue format. We have fabricated an aspherical plasma etched lens using the selectivity control transfer technique.

Near-field recording for the disc mastering process was realized. A high-numerical-aperture (NA) objective (NA=1.4) composed of an aspherical lens and a solid immersion lens (SIL) was driven by an air pad and a piezotransducer. The gap between the SIL and the glassmaster was controlled by a new gap detection method using the totally internally reflected beam from the bottom surface of the SIL. In the near-field operation, the gap was maintained at 100 nm with a residual error of ±4.8 nm. In the DC exposure with a laser beam of 413 nm, a narrower groove structure could be formed almost at the inverse rate of NA expansion. In the read-only memory (ROM) exposure with an eight to fourteen modulation plus (EFM+) signal, signal bottom jitter values of 9.8% for an 18 GB disc and 10.9% for a 20 GB disc were obtained.