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The demonstration of optical processing based on spectral line-by-line pulse shaping on an optical frequency comb generator (OFCG) is discussed. Findings reveal the generation of transform-limited 1.6-ps short pulses at 10 GHz due to the direct combination of two pulses in each period from the OFCG.

We propose a novel, to our knowledge, silicon planar-apertured probe array as an optical head for high-density near-field optical storage. In comparison with a conventional fiber probe employed for near-field optical storage the apertured probe array has a higher readout data-transmission rate and better mechanical durability. A probe array with an aperture size of 100 nm was fabricated by use of photolithography and wet etching of a silicon wafer. Subwavelength-readout capability was demonstrated by use of one aperture of the probe array. Furthermore, we achieved a 16 times increase in the light-transmission efficiency of the probe array by installing glass-sphere microlenses on each aperture. The increase was confirmed by measurement of the near-field optical intensity.

A study was conducted to examine frequency difference measurements and noise analysis associated with an optical frequency comb in optical fibers. The frequency comb supported a coherent nature that was analyzed by heterodyne-detecting the sidebands offset by up to 12 THz from the carrier. Each beat signal was then maintained within a few megahertz while phase noise pedestal power increased with the offset frequency.

The optical frequency difference measurement of 1.5 micrometer wavelength semiconductor lasers is measured using a specially devised wide-span optical frequency comb (OFC) generator which consists of a high frequency electrooptic phase modulator, LiNbO3, installed in a Fabry-Perot cavity. The span of the OFC is wider than 4 THz of 1 kHz spectrum linewidth and a sensitive optical balanced-mixer-receiver. It is possible to measure frequency difference up to 0.5 THz with signal-to-noise ratio higher than 61 dB.