Kabushiki Kaisha Toshiba

Hitachi, Ltd.

Hokuto Electronics Co., Ltd.

Mitsuhiro Oikawa

Tsutomu Ishii

Takeshi Takahara

Kiyoshi Inoue

Masaaki Tamatani

Takeo Itou

Hidemi Matsuda

Norio Koike

Hirofumi Takemura

Hidenobu Taniguchi

Yohe Shimizu

Kazuaki Higuchi

Yoshinori Tetsuishi

Toshifumi Takehara

Yutaka Tagawa

Yoshifumi Chujo

To verify a qualification on a network without notifying verifier privacy information that can identify as a subject of a public key certificate while keeping safety of the public key infrastructure technology. An attribute certificate validation method wherein by preparing an environment in which only an attribute certificate validation device operated by a trusted third party can access a user's public key certificate, the verifier transmits attribute certificate and signed data received from a user having presented a qualification, to the attribute certificate validation device to thereby request the device to make a check to confirm authenticity of the holder of the attribute certificate, thereby preventing the public key certificate (particularly, privacy information contained in the public key certificate) of the user from being passed to the verifier.

Attribute certificate validation method and device

Without modifying application programs in a smart card, data and functions of the application programs can be used by one authentication operation if an apparatus has an invented authentication information management function utilization part. Even if the apparatus not implemented with the invention can use the smart card in a similar manner to the conventional manner. An authentication information management program for managing information necessary for authentication of each application is introduced into the smart card. When each application is utilized, the authentication information management program acquires the application authentication information after an authentication request message from the application program is captured, and transmits the application authentication information to the application program. It is possible to realize a method of utilizing data and functions possessed by the application programs through one authentication operation.

Authentication information management method for device embedded with microprocessor unit

An electroluminescent phosphor includes a phosphor powder that has zinc sulfide as a phosphor host. The phosphor powder has an average particle size, which is expressed by a D(50) value, in the range of 10 &mgr;m or more and 20 &mgr;m or less. In addition, the phosphor powder has a particle size distribution, in which coarser particle component, of which particle size is 31 &mgr;m or more, is 15% by mass or less. An electroluminescent element includes a luminescent layer that includes such electroluminescent phosphor, and of which particle density is heightened on the basis of the average particle size and the particle size distribution of the phosphor powder. A transparent electrode layer is integrally disposed to face one main surface of the luminescent layer, and a rear electrode layer is integrally disposed through a reflective insulating layer on the other main surface. According to such electroluminescent element, brightness may be improved.

Electroluminescent phosphor and electroluminescent element therewith

An electroluminescent phosphor comprises zinc sulfide as a phosphor base material, at least one kind selected from copper and manganese as an activator, and at least one kind selected from chlorine, bromine, iodine, and aluminum as a coactivator. The content of alkaline earth metal elements in the electroluminescent phosphor is 0.05% by weight or less. In addition, the electroluminescent phosphor includes cesium in the range of 0.0001% by weight or more and 0.01% by weight or less. Such an electroluminescent phosphor has excellent brightness and life. An electroluminescent element comprises a phosphor layer in which an electroluminescent phosphor is dispersed in a dielectric. The electroluminescent phosphor includes reduced amount of alkaline earth metal elements and a slight amount of cesium.

Electroluminescent phosphor and electroluminescent element using the same

A method for regenerating a fluorescent material from a recovered phosphor slurry characterized by including a chemical washing step wherein a hypochlorite and a periodate are used; a carbon removing step for floating carbon in the supernatant liquid by the use of ammonia thereby removing the carbon; an acid washing step; and a heat treating step in this order as well as a system for regenerating a fluorescent material comprising means for effecting the aforesaid steps. From this constitution, it becomes possible that impurities are easily and effectively removed from the recovered phosphor slurry, whereby a fluorescent material providing excellent luminance and excellent grade of phosphor film can be regenerated.

Regenerating method and system for fluorescent material

Zinc silicate phosphor emitting green for cathode ray tubes with a long persistence, which does not contain arsenic.

Cathode ray tube containing zinc silicate phosphor

A cathode-ray tube according to the present invention is provided with a phosphor screen comprising phosphors A, B, and C, wherein each of the phosphors A and B constitute 5 to 15% by weight and, the phosphor C constitutes 70 to 90% by weight. The phosphor A is a bluish white-emitting phosphor (Y.sub.1-x-y Gd.sub.x Tb.sub.y).sub.2 O.sub.2 S (0.ltoreq.X.ltoreq.0.999999 and 0.000001.ltoreq.Y.ltoreq.0.001), the phosphor B is at least one of a blue-emitting silver-activated hexagonal zinc sulfate (ZnS:Ag) phosphor, etc., and the phosphors C is a yellow-emitting phosphor (In.sub.1-p-r M.sub.p TB.sub.q Eu.sub.r BO.sub.3) (wherein M is at least one element selected from the group consisting of Sc, Lu, Y, Gd, and Ga, and p, q, and r satisfy 0.ltoreq.p.ltoreq.0.2, 0.0005.ltoreq.q.ltoreq.0.05, and 0.001.ltoreq.r.ltoreq.0.1). The cathode-ray tube of the present invention is a phosphor screen which is free from toxicity and has good flickering and brightness characteristics and high current dependence of brightness.

Cathode-ray tube including a white phosphor screen

In a cathode ray tube with a phosphor screen containing a Zn type green emitting phosphor, e.g. ZnS, ZnCdS and Zn.sub.2 SiO.sub.4, the surface of the phosphor particle includes a surface area of (Co,Zn)O. The surface area is green colored to operate as a filter against incident light from outside the tube and reduces background brightness of picture images caused by excitation of scattering electrons. Thus, the contrast of the picture images rises. The contrast is further increased by Ni doped.

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Yokohama, Japan

Mitsuhiro Oikawa