Sony Magnescale Inc.

Sony Corporation

Nec Corporation

Mori Seiki Co., Ltd.

Sony Magnescale Incorporation

Hideki Tsuchiya

Kayoko Taniguchi

Kenichi Sato

Hideaki Tamiya

Akihiro Kuroda

Hiroyuki Ohkubo

Masaaki Toyama

Masahito Kon

Yasuhiko Onodera

Disclosed is a displacement measuring apparatus that includes a composite scale having a magnetic pattern and a diffraction grating each aligned in a direction of measuring axis, and a detector head moving in a direction of measuring axis relative to the composite scale. The detector head has a magnetic detection unit detecting a magnetic field exerted by the magnetic pattern to generate first reproduced signals, a light source irradiating the diffraction grating with light, and an optical detection unit detecting the light diffracted by the diffraction grating to generate second reproduced signals. In composite scale, the magnetic pattern and the diffraction grating are arranged such that a pitch of the first reproduced signals is larger than that of the second reproduced signals.

Displacement measuring apparatus

In each of discharge cells of a color plasma display panel, a data electrode is formed so as to cover entire side walls and bottom of the cell. A fluorescent layer is also formed on an entire surface of the data electrode to improve brightness. The barriers are provided by forming a plurality of grooves a glass substrate to reduce flicker of a screen. The surface of the substrate is made black to improve a display contrast.

Color plasma display panel and fabricating method

A reflection type hologram scale, in which a hologram dry plate is bonded to a protecting base member in which a hologram grating formed on a scale base member forming the hologram dry plate and a reflecting film formed on a base member forming the protecting base member are opposed to each other. Therefore, the hologram grating and the reflecting film are both protected by the scale base member and the base member so that the hologram grating and the reflecting film are prevented from being exposed to the air, thereby preventing the hologram grating and the reflecting film from being smudged by fingermarks, dust and also from being scratched.

Reflection type hologram scale

An apparatus for making a hologram scale is comprised of a reference diffraction grating on which a light becomes incident and from or by which the incident light is emitted or reflected as a diffracted light, and a recording material, wherein at least two diffracted lights of the diffracted light are caused to interfere with each other as an object wave and a reference wave so as to form a hologram scale on the recording material. Further, an apparatus for making an assembled hologram scale, a hologram scale, an assembled hologram scale and a moving member having a hologram scale are also provided.

Hologram scale, apparatus for making hologram scale, moving member

A hologram scale having a base substrate, a hologram film with a diffraction grating of a desired pitch exposed thereon, adhered to the base substrate, and with a protective substrate to protect the hologram film is manufactured by the following method: a hologram of a laser produced diffraction grating is formed on a holographic film to act as a scale. This film is applied on a central portion of a base substrate. Adhesives having moisture resistance are applied between the base and the protective substrates to essentially surround the hologram film positioned on the base substrate. The protective and the base substrates are sealed integrally by the adhesives, securing the hologram film therein so as to protect it from ambient environmental conditions.

Hologram scale having moisture resistance

Optical instrument for measuring displacement comprising a movable diffraction grating used as a scale, a semiconductor laser device, photodetectors, and means for making two light beams diffracted by the diffraction grating interfere with each other in which displacement of said diffraction grating is measured, based on variations of interference signals. The laser device has a suitable coherency for making selectively two necessary light beams with equal optical path lengths interfere with each other.

Growing community of inventors

Kanagawa, Japan

Hideki Tsuchiya