Fuji Xerox Co., Ltd.

Fuji Xerox Corporation

Keiichi Nashimoto

Hiroaki Moriyama

Takashi Morikawa

Shigetoshi Nakamura

Masao Watanabe

Atsushi Masuda

Eisuke Osakabe

Masao Ito

Koichi Haga

An optical waveguide element capable of being coupled with optical fibers at high coupling efficiency is to be provided. Also an optical waveguide element manufacturing method permitting accurate production of such optical waveguide elements is to be provided. The optical waveguide element is provided with a buffer layer formed over a monocrystalline substrate and an optical waveguide layer formed over the buffer layer, and a recess is formed in the buffer layer along the lengthwise direction of the monocrystalline substrate. The optical waveguide layer is provided to fit into this recess to form a channel optical waveguide. Over the upper face of the optical waveguide layer on the light incidence side and the light emission side, a cladding layer whose refractive index is smaller than that of the optical waveguide layer and whose thickness increases towards the end face(s) in a flared shape is provided in the same width as that of the monocrystalline substrate. By providing the cladding layer whose refractive index is smaller than that of the optical waveguide layer, it is made possible to expand the mode field diameter and substantially reduce the coupling loss between the optical fiber and the optical waveguide element. Further by increasing the thickness of the cladding layer in a flared shape toward the end face(s), it is made possible to gradually compress the mode field diameter and to reduce the optical propagation loss within the optical waveguide.

Optical waveguide element, manufacturing method for optical waveguide element, optical deflecting element, and optical switching element

An optical device assures high speed drive, excellent temperature stability, low drive voltage and small crosstalk and insertion loss. The optical device includes a single crystal substrate which is used as a conductive or semiconductive lower electrode, an epitaxial buffer layer consisting of an oxide provided on the single crystal substrate, an epitaxial optical waveguide layer with an oxide ferroelectric material having an electro-optic effect which is provided on the buffer layer and which has a channel optical waveguide of which an optical path is switched when a voltage is applied to the branching portion between an optical path for incident light and an optical path for outgoing light, and a couple of upper electrodes for applying a voltage to the branching portion of the channel optical waveguide.

Optical device, driving method of optical device and manufacture of optical device

The present invention uses a single substrate to provide a small-size optical waveguide element that requires no optical axis adjustments, can be driven at a low voltage, is excellent in light utilization efficiency, and can rapidly two-dimensionally deflect a light beam. A right-triangle upper electrode and a rectangular transparent upper electrode are formed on top of a thin-film optical waveguide formed on a conductive substrate to serve as a lower electrode, and an emission right-angled prism is secured on top of the transparent upper electrode. A voltage is applied between the upper electrode and the conductive substrate, and between the transparent upper electrode and the conductive substrate. A horizontal deflection is performed upon application of a voltage to the upper electrode and a vertical deflection is performed upon application of a voltage to the transparent upper electrode.

Optical deflection element

In an optical waveguide device, a laser beam is collected to an end face of a channel waveguide, and introduced into a PLZT thin film optical waveguide. The incident laser beam, when emitted from the channel waveguide, diverges in the PLZT waveguide, permeates a thin film lens and is collimated into 0.4 Mm size. When a high frequency voltage is not applied to a comb Al electrode, the laser beam is collected after penetrating through the second thin film and emitted from the end face through the channel waveguide to form an emission beam. When the high frequency voltage is applied to the comb Al electrode, a diffraction grating is formed by an acousto-optic effect, and the laser beam is deflected. The deflected laser beam, when penetrating through the second thin film lens, is collected and emitted from the end face through the channel waveguide in adjacent with the above-described channel waveguide to form a deflected emission beam.

Optical waveguide device and manufacturing method thereof

The invention intends to provides an optical waveguide device having a structure that satisfies the low drive voltage characteristic and the low propagation loss characteristic at the same time. The optical waveguide device contains a conductive or semiconductive lower electrode, an epitaxial or single orientational buffer layer provided on the lower electrode, an epitaxial or single orientational optical waveguide provided on the buffer layer, and an upper electrode of a conductive thin film or a semiconductive thin film, provided on the optical waveguide. The optical waveguide device is able to modulate, switch, or deflect incident light beams guided into the optical waveguide by applying a voltage between the upper electrode and the lower electrode.

Opical waveguide device

An optical scanning device for deflecting a plurality of light beams is disclosed. The device includes a plurality of deflection means for deflecting each of the plurality of light beams. The means are formed in a thin film waveguide, and distributes a refractive index of the waveguide by an electro-optic effect according to input signals to cause diffraction due to the distributed refractive index, thereby deflecting a plurality of light beams.

Optical scanning device and image forming apparatus

An oxide thin film comprising an oxide represented by ABO.sub.3, wherein A comprises at least one element selected from the group consisting of the groups IA, IIA, IIIA, IVB and VB of the periodic table, and B comprises at least one element selected from the group consisting of the groups IVA and VA of the periodic table, wherein said oxide thin film has a mixed structure in which crystal grains are dispersed in an amorphous phase or an ultrafine grain phase. The oxide thin film is prepared by preparing an organic solvent solution (1) of a metal alkoxide compound of A and a metal alkoxide compound of B; adding water, or water and a catalyst to the organic solvent solution (1) to prepare a solution (2); mixing the organic solvent solution (1) and the solution (2) to prepare a mixed solution; coating the mixed solution on a substrate to form a thin film; and subjecting the thin film to heat treatment.

Oxide thin film and process for forming the same

The present invention is to provide a production method of a ferroelectric thin film element comprising an epitaxial ferroelectric thin film having stable composition control, an optical smoothness of the surface, and a high crystallization. In the production method, carrying out a first solid phase epitaxial growth process where a first organometallic compound is applied on the single-crystalline substrate and heated to form a ferroelectric buffer layer on a single-crystalline substrate, having a composition different from the substrate with a film thickness of 1 nm to 40 nm; carrying out at least once a second solid phase epitaxial growth process where a second organometallic compound is applied on the ferroelectric buffer layer formed in the above process and heated to form a ferroelectric single layer thin film with a film thickness of 10 nm or more, and being thicker than the ferroelectric buffer layer.

Ferroelectric thin film element and production method thereof

An oriented ferroelectric thin film element, which comprises a single-crystal substrate having thereon (a) a first epitaxial or oriented ferroelectric thin film prepared by a gas phase growth method and (b) a second epitaxial or oriented ferroelectric thin film prepared by application of a coating solution of an organic metal compound to the first ferroelectric thin film followed by heating the coated material. The oriented ferroelectric thin film element has a smooth surface and is useful as an optical guide element, light modulation element, etc. The second ferroelectric thin film can be formed by repeating the process of application of a coating solution of an organic metal compound followed by heating the coated material several times. The present invention also discloses a process for preparing the oriented ferroelectric thin film element.

Oriented ferroelectric thin film element and process for preparing the

An optical deflecting device of optical waveguide type comprising: a conductive or semi-conductive monocrystalline substrate, or a monocrystalline substrate having a conductive or semi-conductive, epitaxial or oriented film provided on the surface thereof; an optical waveguide comprising an epitaxial or oriented ferroelectric film provided on the surface of the monocrystalline substrate; and an upper electrode disposed on top of the optical waveguide. In the optical deflecting device, the conductive or semi-conductive monocrystalline substrate, or the conductive or semi-conductive, epitaxial or oriented film provided on the monocrystalline substrate acts as a lower electrode. The laser beam introduced into the optical waveguide is deflected by applying a voltage between the upper electrode and the lower electrode.

Optical deflecting device

An optical scanning device having a scanning speed which can be used in a laser beam printer, a digital copier, a facsimile apparatus or the like, an optical scanning method using the optical scanning device, and an image forming apparatus using the optical scanning device are disclosed. The optical scanning device comprising: a light source for emitting a laser beam having a constant divergent angle; a thin film waveguide; means for coupling the laser beam to said thin film waveguide; and a comb-like electrode for exciting a surface acoustic wave of a high frequency sweep signal so that the laser beam is deflected to be output as parallel rays.

Optical scanning device, optical scanning method, and image forming

An oriented ferroelectric thin film element has a structure in which an epitaxial or oriented buffer thin film is formed on a semiconductor single crystal substrate, an epitaxial or oriented metallic thin film is formed on the buffer thin film, and an epitaxial or oriented ferroelectric thin film is further formed on the metallic thin film. The semiconductor single crystal substrate may be made of Si or GaAs, the buffer thin film may be made of MgO or MgAl.sub.2 O.sub.4, the metallic thin film may be made of Pd, Pt, Al, Au, or Ag, and the ferroelectric thin film has an ABO.sub.3 perovskite crystal structure.

Oriented ferroelectric thin film element

A buffer layer having crystal orientation In a (111) face is formed on a semiconductor single-crystal (100) substrate and a ferroelectric thin film having crystal orientation in a (111) or (0001) face is then formed over the buffer layer. The buffer layer is preferably formed of MgO at a temperature ranging from 20.degree. to 600.degree. C. and at a rate ranging from 0.5 to 50 .ANG./sec. The thus formed ferroelectric thin film has its axes of polarization aligned in one direction. Using the oriented ferroelectric thin-film device, highly functional nonvolatile memories, capacitors or optical modulators can be fabricated on semiconductor substrates.

Oriented ferroelectric thin-film element and manufacturing method

An optical scanning device of the thin film waveguide type, which has a scanning speed and excellent scanning accuracy that can be used in a laser beam printer, a digital copier, a facsimile apparatus or the like, and an image forming apparatus using the optical scanning device are disclosed. The optical scanning device comprising: a thin film waveguide; a light source for emitting a plurality of laser beams to the thin film waveguide; a comb-like electrode for exciting a surface acoustic wave for deflecting the laser beams in the thin film waveguide; and a plurality of emitting means for emitting the deflected laser beams to an outside of the thin film waveguide, the emitting means being equal in number to the laser beams is disclosed. In an embodiment, the plurality of emitting means are located at the same position in a traveling direction of the incident laser beams, and have different emittance angles. In another embodiment, the plurality of emitting means are located at different positions in a traveling direction of the incident laser beams, and have the same emittance angle.

Optical scanning device and image forming apparatus using the same

An oriented conductive thin film useful as a thin film electrode or a thin film resistor is disclosed, comprising an epitaxial or oriented ABO.sub.3 type oxide (e.g., BaPbO.sub.3) conductive thin film which is obtained by coating a single crystal oxide substrate or a single crystal semiconductor substrate with a solution of a metal oxide precursor comprising an organometallic compound, thermally decomposing the coating layer, followed by annealing. An epitaxial or oriented ABO.sub.3 type ferroelectric thin film may further be provided on the conductive thin film.

Growing community of inventors

Minami-Ashigara, Japan

Keiichi Nashimoto