Abstract: Heat diffusion preventing film is formed on the cleavage plane of a semiconductor laser, and thin film comprising a low melting point material, such as indium, is formed on top on the heat diffusion preventing film. When irradiated by the laser light emitted from the semiconductor laser and heated, the irradiated area of the thin film changes in state from crystalline to amorphous and forms a small light transmitting area. Near field light passes through this light transmitting area. The near field light generating device of the present invention uses a simple construction as described above, and complex adjustment is not required. In addition, problems such as laser oscillation failure do not occur.

Abstract: An optical head has a near-field light generating element generating near-field light; and a beam shaper which shapes an incident beam into a substantially toroidal beam and directs the shaped beam to said near-field light generating element. According to the optical head having the above-described structure, the incident light is shaped into a substantially toroidal beam without being intercepted, incident on the zonal part of the near-field light generating element, and condensed to a minute spot. That is, only the light of the high numerical aperture part is used with efficiency, and the light can be condensed to a minute spot.

Abstract: A radiographic intensifying screen set comprising a pair of a front intensifying screen and a rear intensifying screen, each comprising a support and a plurality of phosphor layers each having a binder resin and a phosphor dispersed therein, provided on the support, wherein at least some of the phosphor layers of the respective front intensifying screen and rear intensifying screen contain a fluorescent dye or a fluorescent pigment which absorbs some of emitted lights from the phosphors and emits lights having other wavelengths, the support for the front intensifying screen is a light-reflective support, and the support for the rear intensifying screen is a light-absorptive support.

Abstract: An optical head has a near-field light generating element generating near-field light; and a beam shaper which shapes an incident beam into a substantially coroidal beam and directs the shaped beam to said near-field light generating element. According to the optical head having the above-described structure, the incident light is shaped into a substantially toroidal beam without being intercepted, incident on the zonal part of the near-field light generating element, and condensed to a minute spot. That is, only the light of the high numerical aperture part is used with efficiency, and the light can be condensed to a minute spot.

Abstract: A radiographic intensifying screen having at least a fluorescent layer and a protective layer on a support, wherein the protective layer has a multi-layer structure comprising at least one layer of an organic macromolecule film and a film-forming resin layer provided on the surface of the organic macromolecule film at least on the side which is not in contact with the fluorescent layer, and the resin of the film-forming resin layer is different from the resin of the organic macromolecule film.

Abstract: This invention relates to a radiographic intensifying screen excellent in sharpness and durability, which comprises a support, a fluorescent layer formed on the support, and a protective layer formed by coating a solution containing a protective layer-forming resin on the fluorescent layer, wherein a water repellent layer or a resin layer which may optionally contain a water repellent is provided between the fluorescent layer and the protective layer, or the fluorescent layer may optionally contain a water repellent, and also relates to a process for preparing the same.

Abstract: A calcium tungstate phosphor which comprises calcium tungstate as a host and vanadium, wherein the proportion of the vanadium to the calcium tungstate is within a range of from 0.01 to 30 ppm. The phosphor is produced by forming a solid calcium tungstate precipitate from an aqueous medium containing ammonia, calcium ion, tungstate ion and vanadate ion and firing the precipitate in the presence of fluxing material.

Abstract: A radiographic intensifying screen comprising a support and a fluorescent layer formed on the support, characterized in that said fluorescent layer is composed essentially of a rare earth oxysulfide phosphor represented by the formula:(Ln.sub.1-x-y-z' Tb.sub.x, R.sub.y, A.sub.z).sub.2 O.sub.2 Swhere Ln is at least one element selected from the group consisting of La, Gd, Y and Lu, R is at least one element selected from the group consisting of Nd and Ho, A is at least one element selected from the group consisting of Pr, Er and Yb, and x, y and z are numbers within the ranges of 0.001.ltoreq.x.ltoreq.0.02, 0.0001.ltoreq.y.ltoreq.0.01 and O.ltoreq.z.ltoreq.0.01, respectively, and x.gtoreq.y+z.

Abstract: A radiographic image conversion screen comprises a support, a first fluorescent layer formed on the support and consisting essentially of a blue emitting phosphor and a second fluorescent layer formed on the first fluorescent layer and consisting essentially of a green emitting rare earth phosphor.

Abstract: A radiographic image conversion screen comprising a support, a first fluorescent layer formed on the support and consisting essentially of a blue emitting phosphor and a second fluorescent layer formed on the first fluorescent layer and consisting essentially of a green emitting rare earth oxysulfide phosphor. The green emitting rare earth oxysulfide phosphor is represented by the formula: (Ln.sub.1-i, Yi, Tba, Rb).sub.2 O.sub.2 S where Ln is at least one element selected from the group consisting of La, Ga and Lu, R is at least one element selected from the group consisting of Dy, Pr, Yb and Nd, and i, a and b are numbers within the ranges of 0.ltoreq.i.ltoreq.0.35, 0.0005.ltoreq.a.ltoreq.0.09 and 0.0002.ltoreq.b.ltoreq.0.01 respectively.

Abstract: A radiographic image conversion screen comprising a support, a first fluorescent layer formed on the support consisting essentially of a blue emitting phosphor and a second fluorescent layer formed on the first fluorescent layer consisting essentially of a green emitting rare earth phosphor.

Abstract: A radiographic image conversion screen comprising a support, a first fluorescent layer formed on the support and consisting essentially of a blue emitting phosphor and a second fluorescent layer formed on the first fluorescent layer and consisting essentially of a green emitting rare earth oxysulfide phosphor. The green emitting rare earth oxysulfide phosphor is represented by the formula: (Ln.sub.1-i, Y.sub.i, Tb.sub.a, R.sub.b).sub.2 O.sub.2 S where Ln is at least one element selected from the group consisting of La, Gd and Lu, R is at least one element selected from the group consisting of Dy, Pr, Yb and Nd, and i, a and b are numbers within the ranges of 0.ltoreq.i.ltoreq.0.35, 0.0005.ltoreq.a.ltoreq.0.09 and 0.0002.ltoreq.b.ltoreq.0.01, respectively.

Abstract: In an intensifying screen composed of a support, a fluorescent layer disposed on the support and a protective layer disposed on the fluorescent layer, the fluorescent layer is composed of one or more phosphors selected from the group consisting of a terbium activated rare earth oxysulfide phosphor, a divalent europium activated alkali earth metal fluorohalide phosphor and a silver activated sulfide phosphor, and the protective layer is a light absorption layer which absorbs a part of light emitted by the fluorescent layer.

Abstract: A radiographic intensifying screen having high radiographic image quality is composed of a support and a fluorescent layer formed on the support. The fluorescent layer contains a pigment coated phosphor in which pigment particles adhere to the surface of the phosphor and partly absorb the light emitted by the phosphor.

Abstract: A complex halide phosphor represented by the following composition formula and an X-ray image converter using the same:(Me.sub.1-f,Mg.sub.f )F.sub.2.aMe' X.sub.2.bKX'.cMe" SO.sub.4 :dEu.sup.2+,eTb.sup.3+wherein Me, Me' and Me" each represents at least one of the alkaline earth metals of the group consisting of barium, strontium and calcium; X and X' each represents at least one of chlorine and bromine; and a, b, c, d, e and f are numbers defined by one of the following five combinations:1. 0.80.ltoreq.a.sub.1 .ltoreq.1.50, 0.10.ltoreq.b.sub.1 .ltoreq.1.50, c.sub.1 =0, 0.001.ltoreq.d.sub.1 .ltoreq.0.20, e.sub.1 =0 and f.sub.1 =0.2. 0.30.ltoreq.a.sub.2 .ltoreq.1.50, 0.10.ltoreq.b.sub.2 .ltoreq.2.00, 0.01.ltoreq.c.sub.2 .ltoreq.1.00, 0.001.ltoreq.d.sub.2 .ltoreq.0.20, e.sub.2 =0 and f.sub.2 =0.3. a.sub.3 =1, b.sub.3 =0, c.sub.3 =0, 0.01.ltoreq.d.sub.3 .ltoreq.0.10, 0<e.sub.3 .ltoreq.0.05 and f.sub.3 =0.4. a.sub.4 =1, b.sub.4 =0, c.sub.4 =0, 0.001.ltoreq.d.sub.4 .ltoreq.0.20, e.sub.4 =0 and 0<f.sub.4 .

Abstract: An X-ray intensifying screen having a high speed and capable of providing good image quality superior in sharpness, granularity and contrast comprising a support having formed thereon a fluorescent layer composed of a complex halide phosphor represented by the composition formula shown below and having further formed on the fluorescent layer another fluorescent layer composed of a calcium tungstate phosphor:(Me.sub.1-f, Mg.sub.f)F.sub.2 .multidot.aMe'X.sub.2 .multidot.bKX'.multidot.cMe"SO.sub.4 :dEu.sup.2+,eTb.sup.3+wherein Me, Me' and Me" each represents at least one of the alkaline earth metals of the group consisting of barium, strontium and calcium; X and X' each represents at least one of chlorine and bromine; and a, b, c, d, e and f are the numbers defined by one of the following five combinations:1. 0.80.ltoreq.a.sub.1 .ltoreq.1.50, 0.10.ltoreq.b.sub.1 .ltoreq.1.50, c.sub.1 .dbd.0, 0.001.ltoreq.d.sub.1 .ltoreq.0.20, e.sub.1 .dbd.0 and f.sub.1 .dbd.0;2. 0.30.ltoreq.a.sub.2 .ltoreq.1.50, 0.10.ltoreq.b.