Shin-etsu Chemical Co., Ltd.

Nippon Hoso' Kyokai

Other

Masanori Ikari

Toshihiko Ryuo

Takuto Matsumoto

Masayuki Tanno

Toshihiro Nomoto

Takao Kuki

Keita Tanaka

Tadakatsu Shimada

Shinji Makikawa

Yoshihiro Nojima

Akio Ikesue

Akira Yahagi

A method of fabricating a ceramic molded body for sintering, which includes molding a raw material powder containing a ceramic powder and a thermoplastic resin having a glass transition temperature higher than room temperature into a predetermined shape by isostatic pressing and in which a first-stage press-molded body is fabricated by subjecting a uniaxially press-molded body fabricated by uniaxially pressing the raw material powder into a predetermined shape or the raw material powder filled in a rubber die to a first-stage isostatic press molding at a temperature lower than a glass transition temperature of the thermoplastic resin and then a ceramic molded body is fabricated by heating this first-stage press-molded body to a temperature equal to or higher than the glass transition temperature of the thermoplastic resin and performing warm isostatic press molding as second-stage isostatic press molding.

Method for preparing ceramic molded body for sintering and method for producing ceramic sintered body

An optical isolator includes a Faraday rotator including a trivalent ion exchange TAG (terbium-aluminum garnet), and arranged around the Faraday rotator, a central hollow magnet and a first and a second hollow magnet units arranged to sandwich the central hollow magnet in an optical axis direction. A magnetic flux density B [T] in the Faraday rotator and an optical path length L [mm] where the Faraday rotator is arranged satisfy0<  (1) and14.0≤≤24.0  (2). The optical isolator, compared with a conventional Faraday rotator such as a terbium-gallium garnet (TGG) crystal, contributes to reduction of a thermal lensing effect, being a pending problem, in a high-output fiber laser.

Optical isolator

Provided is a transparent spinel sintered body which is formed from an Mg&#x2014;Al spinel powder having an Al/Mg ratio of from 1.97 to 2.03 or a mixed powder of an Mg oxide and an Al oxide, and wherein the total content of metal impurities excluding Al and Mg is less than 100 ppm. A sample of this transparent spinel sintered body having a thickness of 3 mm has a total light transmittance of 80% or more in the thickness direction for the wavelength range of from 190 nm to 400 nm; and this transparent spinel sintered body is usable as a medium that transmits light from an ultraviolet light emitting element.

Transparent spinel sintered body, optical member and method for producing transparent spinel sintered body

A paramagnetic garnet-type transparent ceramic is a sintered body of complex oxide represented by the following formula (1), comprising SiOas a sintering aid in an amount of more than 0% by weight to 0.1% by weight or less, and has a linear transmittance of 83.5% or more at the wavelength of 1,064 nm for an optical path length of 25 mm:(TbYSc)(AlSc)O&#x2003;&#x2003;(1)wherein 0.05&#x2264;x&#x3c;0.45, 0&#x3c;y&#x3c;0.1, 0.5&#x3c;1&#x2212;x&#x2212;y&#x3c;0.95, and 0.004&#x3c;z&#x3c;0.2.

Paramagnetic garnet-type transparent ceramic, magneto-optical material and magneto-optical device

A method includes molding a raw material powder containing a ceramic powder and a thermoplastic resin having a glass transition temperature higher than room temperature into a shape by isostatic pressing and in which a raw material powder slurry is prepared by adding the ceramic powder and the thermoplastic resin to a solvent so that the thermoplastic resin is 2% by weight or more and 40% by weight or less with respect to a total weight of the ceramic powder and the thermoplastic resin, a cast-molded body is to formed by wet-casting the raw material powder slurry into a shape, dried, and subjected to first-stage isostatic press molding at a temperature lower than the glass transition temperature of the thermoplastic resin, then this first-stage press-molded body is heated to the glass transition temperature of the thermoplastic resin or above, and warm isostatic press (WIP) molding is performed.

A paramagnetic garnet-type transparent ceramic characterized by being a sintered body of a terbium-containing composite oxide represented by formula (1) in which the linear transmittance at a wavelength of 1,064 nm at an optical path length of 15 mm is 83% or higher.(TbScCe)(AlSc)O&#x2003;&#x2003;(1)(In the formula, 0&#x3c;x&#x3c;0.08, 0&#x2264;y&#x2264;0.01, 0.004&#x3c;z&#x3c;0.16.)

Paramagnetic garnet-type transparent ceramic, magneto-optical material, and magneto-optical device

To a co-precipitating aqueous solution, aqueous solutions containing (a) Tb ions, (b) at least one other rare earth ions selected from the group consisting of Y ions and lanthanoid rare earth ions (excluding Tb ions), (c) Al ions and (d) Sc ions are added; the resulting solution is stirred at a liquid temperature of 50&#xb0; C. or less to induce a co-precipitate of the components (a), (b), (c) and (d); the co-precipitate is filtered, heated and dehydrated; and the co-precipitate is fired thereafter at from 1,000&#xb0; C. to 1,300&#xb0; C., thereby forming a sinterable garnet-type complex oxide powder.

Preparation of sinterable complex oxide powder and manufacturing of transparent ceramics

A slurry or slip composed of a dispersion medium and a dispersoid including sinterable raw material powder containing a complex oxide powder represented by the following formula (1):(TbRSc)(AlSc)O&#x2003;&#x2003;(1)wherein R is yttrium and/or lutetium, 0.05&#x2264;x&#x3c;0.45, 0&#x3c;y&#x3c;0.1, 0.5&#x3c;1-x-y&#x3c;0.95, and 0.004&#x3c;z&#x3c;0.2 is prepared; the slurry or slip is subsequently enclosed in a mold container to be subjected to solid-liquid separation by centrifugal casting to mold a cast compact; the cast compact is dried thereafter; a dried compact is degreased; a degreased compact is sintered thereafter; and a sintered body is further subjected to a hot isostatic pressing treatment to obtain the transparent ceramic material composed of the sintered body of garnet-type rare earth complex oxide represented by the formula (1).

Method for manufacturing transparent ceramic material for faraday rotator

A garnet-structure complex oxide powder having formula (1) is prepared by adding an aqueous solution containing (a) Tb ion, an aqueous solution containing (b) Al ion, and an aqueous solution containing (c) Sc ion to a co-precipitating aqueous solution, to induce a co-precipitate of components (a), (b) and (c), filtering, heat drying and firing the co-precipitate.(RSc)(ASc)O&#x2003;&#x2003;(1)R is yttrium or a lanthanoid element, typically Tb, A is a Group 13 element, typically Al, x and y are 0&#x3c;x&#x3c;0.08 and 0.004&#x3c;y&#x3c;0.16.

Preparation of sinterable garnet-structure complex oxide powder and manufacturing of transparent ceramics

This invention provides a transparent magnetooptical material that is suitable for use in a magnetooptical device such as an optical isolator. Said magnetooptical material comprises either a transparent ceramic consisting primarily of a complex oxide that can be represented by formula (1) or a single crystal of such a complex oxide. Said magnetooptical material does not absorb fiber-laser light in the 0.9-1.1 &#x3bc;m wavelength range, does not cause heat lensing, and has a higher Verdet constant than TGG crystals, with a Verdet constant of at least 0.14 min/(Oe&#xb7;cm) at a wavelength of 1,064 nm.TbRO&#x2003;&#x2003;(1)(In formula (1), R represents one or more elements selected from among the group consisting of silicon, germanium, titanium, tantalum, tin, hafnium, and zirconium (but not silicon only, germanium only, or tantalum only)).

Magnetooptical material, manufacturing method therefor, and magnetooptical device

Provided, as a transparent magneto-optical material which does not absorb fiber laser light within a wavelength range of 0.9-1.1 &#x3bc;m and is thus suitable for constituting a magneto-optical device such as an optical isolator wherein the formation of a thermal lens is suppressed, is a magneto-optical material which is composed of a transparent ceramic that contains a complex oxide represented by formula (1) as a main component, or which is composed of a single crystal of a complex oxide represented by formula (1).TbRO&#x2003;&#x2003;(1)(In the formula, 0.800&#x3c;x&#x3c;1.00, and R represents at least one element selected from the group consisting of silicon, germanium, titanium, tantalum tin, hafnium and zirconium (excluding the cases where R represents only silicon, germanium or tantalum)).

Magneto-optical material, method for producing same and magneto-optical device

Provided is a magneto-optical material which does not absorb fiber laser light in a wavelength range of 0.9-1.1 &#x3bc;m and does not cause a thermal lens, while having a larger Verdet constant than TGG crystals, and which is suitable for constituting a magneto-optical device such as an optical isolator. This magneto-optical material is formed of a single crystal of a rare earth oxysulfide that is represented by formula (1) or a transparent ceramic which contains, as a main component, a rare earth oxysulfide that is represented by formula (1), and this magneto-optical material has a Verdet constant of 0.14 min/(Oe&#xb7;cm) or more at the wavelength of 1,064 nm.(TbR)OS&#x2003;&#x2003;(1)(In the formula, x is 0.3 or more but less than 1; and R represents at least one rare earth element that is selected from the group consisting of yttrium, lutetium, gadolinium, holmium, scandium, ytterbium, europium and dysprosium.)

Provided is a light transmitting metal oxide sintered body manufacturing method for obtaining a light transmitting sintered body, the main component of which is metal oxide, by carrying out hot isostatic pressing at a HIP heat processing temperature (T) set in a temperature range of 1000-2000&#xb0; C. The light transmitting metal oxide sintered body manufacturing method, by which light transmitting properties can be improved, is characterized by the following: in the temperature elevating step of the hot isostatic pressing, a temperature range (S) from room temperature to the HIP heat processing temperature (T) is divided into a plurality of stages; for each divided stage the temperature elevation rate is controlled; and the temperature elevation rate of a final stage (14) that includes at least the HIP heat processing temperature (T) is 10&#xb0; C./h to 180&#xb0; C./h.

Light transmitting metal oxide sintered body manufacturing method and light transmitting metal oxide sintered body

Provided is a method of manufacturing a transparent sesquioxide sintered body by which a transparent MOtype sesquioxide sintered body can be manufactured. A powder including particles of an oxide of at least one rare earth element selected from Y, Sc or lanthanide elements and Zr oxide particles is prepared as a raw material powder, wherein in the particle size distribution of the rare earth element oxide particles, or in the particle size distribution of secondary particles in the case where the rare earth element oxide particles are agglomerated to form the secondary particles, the particle diameter Dvalue at which the cumulative particle amount from the minimum particle size side is 2.5% based on the total particle amount is in the range from 180 nm to 2000 nm, inclusive. The raw material powder is press molded into a predetermined shape, followed by sintering.

Method of manufacturing transparent sesquioxide sintered body, and transparent sesquioxide sintered body manufactured by the method

A polarization-independent optical isolator includes a first birefringent wedge plate having an inclined plane directed to a light incoming side; a second birefringent wedge plate having an inclined plane directed to a light outgoing side, the wedge equal thickness line of the inclined plane of the second birefringent wedge plate being in parallel to the wedge equal thickness line of the inclined plane of the first birefringent wedge plate; and a Faraday rotator element disposed between the first and second birefringent wedge plates. A non-inclined plane of the first birefringent wedge plate is adhesively bonded to a light incoming plane of the Faraday rotator element, and a light outgoing plane of the Faraday rotator element is adhesively bonded to a non-inclined plane of the second birefringent wedge plate. The first and second birefringent wedge plates and the Faraday rotator element thus adhesively bonded to each other are disposed in a cylindrical magnet.

Growing community of inventors

Annaka, Japan

Masanori Ikari