Nippon Telegraph and Telephone Corporation

Tetsuyoshi Ishii

Toshiaki Tamamura

Katsunari Okamoto

Saburo Imamura

Takashi Kurokawa

Kazunori Naganuma

Hirokazu Takenouchi

Hiroyuki Tsuda

Kenji Kurihara

Hiroshi Nozawa

Takashi Kurihara

Toshio Watanabe

Yasuyuki Inoue

Tadayuki Imai

Seiji Toyoda

Satoru Tomaru

Shoichi Hayashida

Shogo Yagi

Naoki Ooba

Tadahito Matsuda

Makoto Hikita

Haruki Kozawaguchi

Katsuhiro Harada

Shigeru Moriya

A laminated optical medium for read-only information recording has ultra-high memory capacity and reliably extracts desired information from laminated memories. Methods for low-cost mass production of laminated read-only medium are demonstrated. The optical medium is a lamination of planar type waveguides made of polymeric materials, in which each waveguide has information recorded as periodic scattering factor to generate scattered light by injection of input light into a waveguide layer. Therefore, read-only information recording medium of ultra-high memory capacity, equivalent to the memory capacity achievable by volume holography, can be produced by using a low-cost planar holographic technique. The laminated medium is simple and energy conserving, because it does not require rotation mechanisms for reproduction of music and video holographic recordings. The medium is ideally suited as identification card, because the card is difficult to counterfeit and a high level of extra information can be stored conveniently for use in a wide range of potential applications.

Read-only laminated information recording medium and manufacturing method therefor

An optical signal processing apparatus includes a first optical waveguide and a first slab waveguide configured to equally distribute an output light of the first optical waveguide. A first arrayed waveguide includes an aggregate of optical waveguides changing in optical length by a constant interval for dividing the output light. A second slab waveguide focuses the optical output of the first arrayed waveguide. A spatial filter receives incident light focused by the second slab waveguide and distributes the incident light on a straight line. The spatial filter also modulates the light into a desired amplitude according to the position on the straight line. The apparatus also includes a second arrayed waveguide and an aggregate of optical waveguides changing in optical length by a constant interval for applying light modulated by the spatial filter to the second arrayed waveguide. Structure is provided for converging the output light of said second arrayed waveguide to a single point. The resulting output light is then appiled to a second optical waveguide.

Optical signal processing apparatus and optical signal processing method

A resist material having a resist and particles mixed into the resist, a major component of the particles being a cluster of carbon atoms, is provided. A method for fabricating a resist material is also provided, the method repeatedly performing: a first step of coating a substrate with a resist film; and a second step of depositing particles whose major component is a cluster of carbon atoms on the resist film. Accordingly, a resist film with high etching resistance can be obtained, and it is possible to realize a reduction in the thickness of the resist film, improvements of contrast of resist patterns; resist sensitivity; heat resistance of resist films; mechanical strength of resist patterns; and further, stabilization of resist sensitivity. Therefore, highly precise fine pattern fabrication can be realized.

Resist material and fabrication method thereof

The present invention relates to an optical signal processing apparatus and optical signal processing method which enable generation, waveform shaping, waveform measurement, waveform recording, correlation processing, and the like of optical pulses of 1-10 ps. A basic construction of the optical signal processing apparatus includes an optical waveguide, a first structure for equally distributing output light of the optical waveguide, an optical waveguide comprising an aggregate of optical waveguides changing in optical length by a constant interval, a arrayed waveguide for dividing the output light, second structure for focusing optical output of the arrayed waveguide, and a mirror for receiving and reflecting incident light focused by the second structure. Or, the apparatus includes an optical waveguide, first structure for equally distributing output light of the optical waveguide, a arrayed waveguide comprising an aggregate of optical waveguides changing in optical length by a constant interval for dividing the output light, second structure for focusing optical output of the arrayed waveguide, and a spatial filter for receiving light focused by the second structure to distribute the incident light on a straight line and making desired amplitude or phase modulation of the light according to the position on the straight line and reflecting the light.

In a digital thermo-optic switch and an optical ADM filter of the present invention, functional components such as a splitter and a grating structure part formed in the course of an optical circuit as a component are composed of silicone materials which are superior in heat resistance, reduced loss, and low birefringence, thereby achieving sufficiently practical thermal stability, low loss at 1.55 to 1.58 .mu.m band, wavelength selectivity, and cost reduction.

Thermo-optic devices

A resist pattern is formed on a substrate by forming a resist on a substrate and radiating an energy beam carrying predetermined pattern information onto the resist, thereby forming a recessed pattern in a surface portion of the resist so as not to extend through the resist. A flat mask layer is formed on the resist including the recessed pattern. The mask layer is uniformly etched along a direction of thickness thereof until at least a surface of the resist is exposed to allow the mask layer to remain on at least a bottom of the recessed pattern, thereby forming a mask pattern comprising the remaining residual mask layer. Finally, the resist is etched by using the mask pattern as an etching mask.

Method of forming resist micropattern

Growing community of inventors

Isehara, Japan

Tetsuyoshi Ishii