Sumita Optical Glass, Inc.

Nippon Telegraph and Telephone Corporation

Sumita Optical Glass Mfg. Co., Ltd.

Shinobu Nagahama

Naruhito Sawanobori

Yoshinori Yamamoto

Masaaki Yamazaki

Masaaki Otsuka

Koichi Tsuchiya

Masayuki Komiya

Osamu Ishii

Nobuyoshi Baba

Yuhu Wang

Junichi Ohwaki

Koji Nakahata

Junya Yamauchi

Koji Moriya

Atsushi Shibukawa

A white light-emitting device using a fluorescent fiber includes a blue semiconductor light-emitting element () for emitting an excitation light (a), and an optical fiber () having one side end face and the other side end face, the excitation light (a) emitted from the blue semiconductor light-emitting element () being made incident to the one side end face to be guided to the other side end face. The optical fiber () includes a core containing therein a phosphor for emitting wavelength conversion lights by being excited by the excitation light (a) received from the blue semiconductor light-emitting element (), and a cladding member (B) having a light emission surface in its peripheral surface, at least a part of optically multiplexed lights, which are obtained by optically multiplexing the wavelength conversion lights and the excitation light, being emitted through the light emission surface.

White light-emitting device using fluorescent fiber

The present invention provides a high refractive index, high dispersion optical glass for precision molding, being free from harmful materials causing environmental problems, such as lead oxide, etc., and having a low yield temperature, a refractive index (nd) of at least 1.83 and an Abbe number (&#x3bd;d) of at most 26.0 and further providing a low softening property as well as an improved mass production property with less coloration, which is represented in terms of for making up the glass, by the following chemical composition (wt %): 

Optical glass for precision molding

An optical glass suitable for mold forming having a metal composition in wt % in terms of metal oxides calculated from the composition of the following components: PO34&#x2013;50%, LiO 2&#x2013;9%, NaO 7&#x2013;28%, KO 3&#x2013;27%, provided that the total of RO is 17&#x2013;41% (R: Li, Na, K), AlO6.5&#x2013;30%, ZnO 0&#x2013;22%, BaO 0&#x2013;21%, SrO 0&#x2013;18%, CaO 0&#x2013;16%, MgO 0&#x2013;14%, provided that the total of R'O is 0&#x2013;34% (R&#x2032;: Zn, Ba, Sr, Ca, Mg), ZrO0&#x2013;1.5% and F 1.5&#x2013;32% relative to the total weight of the oxides, and exhibits a glass transition temperature (Tg) of 350&#xb0; C. or lower and a specific gravity (Sg) of 3.1 or less and is excellent in chemical durability. The optical glass can be press formed at a low temperature of about 270 to 400&#xb0; C.

Optical glass suitable for mold forming

The present invention provides a high refractive index, high dispersion optical glass for precision molding, being free from harmful materials causing environmental problems, such as lead oxide, etc., and having a low yield temperature (At), i.e. at most 580&#xb0; C., a refractive index (nd) of at least 1.89 and an Abbe number (&#x3bd;d) of at most 23.0 and further providing a low softening property as well as an improved mass production property with less coloration, which is represented in terms of for making up the glass, by the following chemical composition (wt %): 

The present invention provides an optical glass for press molding, in particular, a low softening point glass which contains, in an oxide glass of phosphate type, a durability improving component in addition to glass forming components, and has a weight loss of at most 0.15 weight % in a durability test, and which is represented, in term of elements for making up the glass, by the following chemical composition (mol %):

Optical glass for molding

The object of the present invention is to provide an oxide glass capable of exhibiting a long lasting afterglow and photostimulated phosphorescence, whereby energy can be accumulated by radiation excitation, for example, by &ggr;-rays, X-rays, UV-rays, etc. and light emission can be continued for a long time even after stopping the excitation. That is, the present invention relates to an oxide glass capable of exhibiting a long lasting afterglow and photostimulated luminescence, characterized by a constitutional composition comprising, at least, terbium oxide (Tb O ) or manganese oxide (MnO), gallium oxide (Ga O ) or aluminum oxide (Al O ), alkali metal oxide or alkaline earth metal oxide and boron oxide (B O ) or silicon oxide (SiO ) or zinc oxide (ZnO).

Oxide glass showing long afterglow and accelerated phosphorescence

The present invention provides an optical glass for precision molding, having excellent properties, i.e. yield temperature (At) of at most 550&deg; C., refractive index (nd) of at least 1.83 and Abbe number (&ngr;d) of at most 26.0 and further providing a low softening property as well as an improved mass production property with less coloration, which is represented, in term of atoms for making up the glass, by the following chemical composition (wt %)

The present invention provides an oxide glass capable of exhibiting a long lasting afterglow and photostimulated phosphorescence, can be used not only as a material for confirming an infrared laser or controlling an optical axis, but also as a material for recording or reproducing of &ggr;-rays, X-rays or UV-rays images and further can be used as an optical recording material of such a type that can be read. This glass material is represented, in term of atoms for making up the glass, by the following chemical composition (mol %):

Oxide phosphorescent glass capable of exhibiting a long lasting afterglow and photostimulated luminescence

The present invention provides an oxide glass capable of exhibiting a long lasting afterglow and photostimulated phosphorescence, whereby energy can be accumulated by radiation excitation, for example, by .gamma.-rays, X-rays, UV-rays, etc., light emission can be continued for a long time even after stopping the excitation. Furthermore, the long lasting afterglow and photostimulated luminescence oxide glass can be used not only as a phosphorescent material for night illumination or night signal, but also as a material for confirming an infrared laser or controlling an optical axis because of exhibiting photostimulated luminescence by irradiation of infrared rays or visible rays. In addition, this glass is useful for recording or reproducing of .gamma.-rays, X-rays or UV-rays images. This glass material is represented, in term of atoms for making up the glass, by the following chemical composition (mol %):

Oxide phosphorescent glass capable of exhibiting a long lasting

According to the present invention, there is provided a fluorophosphate fluorescent glass, capable of converting invisible ultraviolet rays into visually observable visible rays with a high efficiency and available for controlling the optical axis of a laser beam such as excimer laser, etc. The feature of this fluorescent glass consists in a fluorophosphate fluorescent glass capable of exhibiting fluorescence in the visible region, having a chemical composition comprising, at least, (I) phosphorus (P), oxygen (O) and fluorine (F), as glass constituting components, and (II) at least one member selected from the group consisting of divalent europium, terbium, samarium and manganese, as a fluorescent agent, the divalent europium being contained as an essential component and at least one of samarium and manganese being contained as an essential component when terbium is contained. In particular, a fluorophosphate fluorescent glass exhibiting a blue fluorescence containing europium as an essential component and a fluorophosphate fluorescent glass exhibiting a white fluorescence containing at least one of samarium and manganese as an essential component are provided.

Fluorophosphate fluorescent glass capable of exhibiting fluorescence in

A new infrared-to-visible up-conversion material is provided which can be applied to an infrared light identification element having a useful conversion efficiency and sensitivity for infrared light in the wavelength of 1.5 .mu.m band, 0.98 .mu.m band and 0.8 .mu.m band without the necessity of previous excitation of the material. This infrared-to-visible up-conversion material consists of an inorganic material comprising at least two elements of erbium (Er) and a halogen or compounds thereof.

Infrared-to-visible up-conversion material

An optical fiber bundle for heat resistance and vacuum resistance which can be used even at a very high temperature or high vacuum is provided in economical manner. This is accomplished by a process for the production of an optical fiber bundle for heat resistance and vacuum resistance, which comprises making up optical fiber filaments each having a core part and a clad part into a bundle, closely fusion-bonding the end of the optical fiber bundle with a bonding glass and then subjecting the bonding glass to a crystallization treatment to increase the heat resistance.

Process for the production of an optical fiber bundle for heat

A fluorophosphate optical glass having optical constants, i.e. a refractive index of 1.45 to 1.54 and an Abbe number of 75 to 90, preferably 75 to 89.5, useful as a lens for an optical instrument to obtain a good quality image, is provided, which has a chemical composition (% by mole) comprising:

Fluorosphosphate optical glass

A fluorophosphate optical glass having optical constants, i.e. refractive index (nd) of 1.54 to 1.60 and Abbe number (.nu.d) of 68 to 75 and having abnormal partial dispersion represented by a relative partial dispersion of at least 0.537 is provided, which has a chemical composition (% by weight) comprising:

Growing community of inventors

Saitama-ken, Japan

Shinobu Nagahama