Hitachi, Ltd.

Hitachi Maxell, Limited

Other

Hitachi Chemical Company, Ltd.

Hitachi Maxwell, Ltd.

Tetsuo Tajima

Ryoichi Sudo

Hiroaki Miwa

Eiji Koyama

Shinkichi Horigome

Toshiaki Taii

Makoto Kobata

Norio Ohta

Yutaka Sugita

Fusaji Shoji

Akira Kageyama

Yoshinori Miyamura

Toshio Niihara

Hitoshi Saito

Kazutoshi Kobayashi

Makoto Iida

Makoto Kitoh

Noboru Mitsugi

Masayoshi Kitadani

Kouji Oikawa

Noboru Terunuma

Chiyoko Iwano

Hiroyuki Onodera

A sheet screen is provided on one of sides of test glass, and a projected image of the test glass is electronically and directly picked up. After tone image signals of the test glass thus picked up are binarized while modifying threshold values according to brightness of a background in the tone image, the number of fragments, the area of the greatest fragment and the length of the longest fragment are calculated. Thus, operations, such as calculating the number of the fragments, can be automatically performed by directly picking up an image of the test glass, allowing a fragmentation test to be carried out with good operability and high precision.

Plate glass shatter testing method, device, imaging method for glass testing and image signal processing method

An optical disc used with an optical head with a focus depth of about 2 micron meter minimizes defects and deterioration in the optical disc at the time of manufacture, during operation and storage thereof as well. The optical disc includes a pair of transparent substrates each provided with at least one layer enabling recording of information, with the pair being bonded and laminated together has an instantaneous axial acceleration<2G.

Optical disc

The object of the present invention is to provide an optical disc and a method of manufacturing thereof wherein defects and deterioration in the optical disc are minimized at the time of manufacture, during operation and storage thereof as well. The invention conceives an optical disc suitable for accomplishing the above object through specifications such as providing a cross-sectional structure thereof comprising a pair of transparent substrates each provided with at least one layer of a recording film formed on the surface of information patterns thereof, with the pair being bonded and laminated with an adhesive, and further providing an instantaneous axial acceleration<2 G measured at room temperatures, a skew angle<5 mrad measured at room temperatures, and a skew angle<5 mrad measured after being left for one hour as heated to 80&deg; C. (otherwise, a shear mass<20 &mgr;m measured after being left for one hour as heated to 80&deg; C.), and still further by utilizing a reaction adhesive the hardness of which after cure is between A30 and A80 in Shore hardness. On the other hand, preferred methods of manufacturing optical discs suitable for implementing the object of the invention were set forth, which utilize reaction adhesives having a Shore hardness after cure between A30 and A80.

Method of manufacturing optical discs

A small-sized heat resisting high voltage transformer and an ignition transformer using the high voltage transformer are provided and utilize both a heat resistant casting resin and a bobbin, which contain an inorganic filler. The high voltage transformer is capable of producing an output voltage of 10-35 kV and comprises a primary coil, a secondary coil, and a magnetic core, wherein a casting resin is injected into the coil part and subsequently cured. The casting resin and bobbin material used for making the coils have heat distortion temperature of at least 130&deg; C., and contain an inorganic filler. The surface of the bobbin may be pretreated. Thereby, adhesion between a bobbin and a casting resin is enhanced to ensure operating properly under the sever heat cycle condition and provide a small-sized heat resistant high voltage transformer.

High voltage transformer and ignition transformer using the same

The object of the present invention is to provide an optical disc and a method of manufacturing thereof wherein defects and deterioration in the optical disc are minimized at the time of manufacture, during operation and storage thereof as well. The invention conceives an optical disc suitable for accomplishing the above object through specifications such as providing a cross-sectional structure thereof comprising a pair of transparent substrates each provided with at least one layer of a recording film formed on the surface of information patterns thereof, with the pair being bonded and laminated with an adhesive, and further providing an instantaneous axial acceleration&lt;2 G measured at room temperatures, a skew angle&lt;5 mrad measured at room temperatures, and a skew angle &lt;5 mrad measured after being left for one hour as heated to 80.degree. C. (otherwise, a shear mass&lt;20 .mu.m measured after being left for one hour as heated to 80.degree. C.), and still further by utilizing a reaction adhesive the hardness of which after cure is between A30 and A80 in Shore hardness. On the other hand, preferred methods of manufacturing optical discs suitable for implementing the object of the invention were set forth, which utilize reaction adhesives having a Shore hardness after cure between A30 and A80.

Optical recording and reproduction apparatus

The object of the present invention is to provide an optical disc and a method of manufacturing thereof wherein defects and deterioration in the optical disc are minimized at the time of manufacture, during operation and storage thereof as well. The invention conceives an optical disc suitable for accomplishing the above object through spcifications such as providing a cross-sectional structure thereof comprising a pair of transparent substrates each provided with at least one layer of a recording film formed on the surface of information patterns thereof, with the pair being bonded and laminated with an adhesive, and further providing an instantaneous axial acceleration&lt;2 G measured at room temperatures, a skew angle&lt;5 mrad measured at room temperatures, and a skew angle&lt;5 mrad measured after being left for one hour as heated to 80.degree. C. (otherwise, a shear mass&lt;20 .mu.m measured after being left for one hour as heated to 80.degree. C.), and still further by utilizing a reaction adhesive the hardness of which after cure is between A30 and A80 in Shore hardness. On the other hand, preferred methods of manufacturing optical discs suitable for implementing the object of the invention were set forth, which utilize reaction adhesives having a Shore hardness after cure between A30 and A80.

An optical disk producing apparatus produces an optical disk by bonding a pair of replica disks together. The replica disks are disposed in a sealed space to oppose to each other with a predetermined gap therebetween. The sealed space is defined by a peripheral wall and opposite ends. The peripheral wall is divided into two portions which are slidingly movable relative to each other. When the sealed space is evacuated, the two portions are moved to apply an atmospheric pressure to the replica disks, so that the replica disks are bonded together into an optical disk.

Optical disk producing apparatus

The object of the present invention is to provide an optical disc, a method of manufacturing thereof and an optical reproduction apparatus including the same wherein defects and deterioration in the optical disc are minimized at the time of manufacture, during operation and storage thereof as well. The invention conceives an optical disc suitable for accomplishing the above object through specifications such as providing a cross-sectional structure thereof comprising a pair of transparent substrates each provided with at least one layer of a recording film formed on the surface of information patterns thereof, with the pair being bonded and laminated with an adhesive, and further providing an instantaneous axial acceleration &lt;2G measured at room temperatures, a skew angle &lt;5 mrad measured at room temperatures, and a skew angle &lt;5 mrad measured after being left for one hour as heated to 80.degree. C. (otherwise, a shear mass &lt;20 .mu.m measured after being left for one hour as heated to 80.degree. C.), and still further by utilizing a reaction adhesive the hardness of which after cure is between A30 and A80 in Shore hardness. On the other hand, preferred methods of manufacturing optical discs suitable for implementing the object of the invention were set forth, which utilize reaction adhesives having a Shore hardness after cure between A30 and A80.

Optical reproduction apparatus

The object of the present invention is to provide an optical disc and a method of manufacturing thereof wherein defects and deterioration in the optical disc are minimized at the time of manufacture, during operation and storage thereof as well. The invention conceives an optical disc suitable for accomplishing the above object through specifications such as providing a cross-sectional structure thereof comprising a pair of transparent substrates each provided with at least one layer of a recording film formed on the surface of information patterns thereof, with the pair being bonded and laminated with an adhesive, and further providing an instantaneous axial acceleration &lt;2 G measured at room temperatures, a skew angle &lt;5 mrad measured at room temperatures, and a skew angle &lt;5 mrad measured after being left for one hour as heated to 80.degree. C. (otherwise, a shear mass &lt;20 .mu.m measured after being left for one hour as heated to 80.degree. C.), and still further by utilizing a reaction adhesive the hardness of which after cure is between A30 and A80 in Shore hardness. On the other hand, preferred methods of manufacturing optical discs suitable for implementing the object of the invention were set forth, which utilize reaction adhesives having a Shore hardness after cure between A30 and A80.

The object of the present invention is to provide an optical disc and a method of manufacturing thereof wherein defects and deterioration in the optical disc are minimized at the time of manufacture, during operation and storage thereof as well. The invention conceives an optical disc suitable for accomplishing the above object through specifications such as providing a cross-sectional structure thereof comprising a pair of transparent substrates each provided with at least one layer of a recording film formed on the surface of information patterns thereof, with the pair being bonded and laminated with an adhesive, and further providing an instantaneous axial acceleration &lt;2G measured at room temperatures, a skew angle &lt;5 mrad measured at room temperatures, and a skew angle &lt;5 mrad measured after being left for one hour as heated to 80.degree. C. (otherwise, a shear mass &lt;20 .mu.m measured after being left for one hour as heated to 80.degree. C.), and still further by utilizing a reaction adhesive the hardness of which after cure is between A30 and A80 in Shore hardness. On the other hand, preferred methods of manufacturing optical discs suitable for implementing the object of the invention were set forth, which utilize reaction adhesives having a Shore hardness after cure between A30 and A80.

This invention relates to insulated wires having good heat resistance and solderability. In particular, wires coated with a polyimide resin or an imide-modified polyurethane resin are provided. They can each be produced by coating a conductor with an insulating coating composition which contains a polyamic acid represented by the following formula: ##STR1## wherein R.sup.1 means a particular tetravalent organic group, R.sup.2 denotes a specific divalent organic group, X is an alkylene or alkylenephenylene group, and n stands for a positive integer.

Insulating coating composition, solderable insulated wires, production

Method of manufacturing an optical disc

This invention relates to a replica plate having a transparent plastic substrate and a photo-cured resin, and a projection type television using the replica plate. An adhesive layer comprising an acrylic or methacrylic compound is provided between a transparent plastic plate and a replica-forming photo-curable resin, whereby it is possible to enhance the adhesion between the surface of the transparent plastic plate and the photo-cured resin, and to produce a replica plate having excellent optical characteristics, good replicating properties and high reliability. The adhesive layer can be provided (1) by coating a layer containing the acrylic or methacrylic compound on the plastic plate, the compound infiltrating into the plate, or (2) by incorporating the acrylic or methacrylic compound into the photo-curable resin, the compound infiltrating therefrom into the plate; in this latter technique, the plate coated with the resin should be heated. This invention has contribution to enhancement of the performance of projection type screens for television, optical parts such as lenses, and products associated with optical disks.

Replica plate, process for producing the same and projection type

A polymer excellent in transparency, mechanical properties, moisture resistance suitable for optical use is obtained by copolymerizing a (meth)acrylate compound (I) and a (meth)acrylate compound (II). ##STR1##

Growing community of inventors

Fujisawa, Japan

Tetsuo Tajima