The present invention relates to an in vitro method for detecting and/or quantifying a biological or chemical substance of interest in a liquid sample, by a capillary action test using, as probes, photoluminescent inorganic nanoparticles, of formula A.sub.1-xLn.sub.xVO.sub.4(1-y)(PO.sub.4).sub.y (II), in which Ln is selected from europium (Eu), dysprosium (Dy), samarium (Sm), neodymium (Nd), erbium (Er), ytterbium (Yb), thulium (Tm), praseodymium (Pr), holmium (Ho) and mixtures thereof; A is selected from yttrium (Y), gadolinium (Gd), lanthanum (La), lutetium (Lu), and mixtures thereof; 0<x<1; and 0≤y<1, said method employing detection of the luminescence, with an emission lifetime shorter than 100 ms, of the nanoparticles, after one-photon absorption, by excitation of the matrix at a wavelength less than or equal to 320 nm.

It also relates to a capillary action test device comprising, as probes, the aforementioned nanoparticles, as well as the use of such a method for purposes of in vitro diagnostics.

Examples of a monolithic phosphor composite for measuring a parameter of an object are disclosed. The ceramic metal oxide phosphor composite is used in an optical device for measuring the parameter of the measuring object. The device comprises a fiber optic probe with a light guide, a light source operatively coupled to the fiber optic probe to provide excitation light into the light guide, a monolithic ceramic metal oxide phosphor composite functionally coupled to a tip of the fiber optic probe, a sensor operatively coupled to the fiber optic probe to detect the emitted light and a processing unit functionally coupled to the sensor to process the emitted light. The monolithic ceramic metal oxide phosphor composite can be embedded in a notch made into the object or can be adhered to a surface of the object with a binder. When the monolithic ceramic metal oxide phosphor composite is illuminated with the excitation light it emits light in a wavelength different from the excitation light and a change in emission intensity at a single wavelength or the change in intensity ratio of two or more wavelengths, a shift in emission wavelength peak or a decay time of the phosphor luminescence is a function of the measuring parameter.

An object is to provide a new type of near-infrared ray-emitting phosphor which exhibits excellent emission intensity. A near-infrared ray-emitting phosphor is represented by a general formula, (Y,Lu,Gd).sub.3-x-y (Ga,Al,Sc).sub.5O.sub.12:(Cr.sub.x,(Yb,Nd).sub.y) (0.05<x<0.3, 0≤y<0.3).

Provided is a light emitting device that includes a light emitting element having a light emission peak wavelength ranging from 380 nm to 490 nm, and a fluorescent material excited by light from the light emitting element and emitting light having at a light emission peak wavelength ranging from 580 nm or more to less than 680 nm. The light emitting device emits light having a ratio R/B of a photon flux density R to a photon flux density B ranging from 2.0 to 4.0 and a ratio R/FR of the photon flux density R to a photon flux density FR ranging from 0.7 to 13.0, the photon flux density R being in a wavelength range of 620 nm or more and less than 700 nm, the photon flux density B being in a wavelength range of 380 nm or more and 490 nm or less, and the photon flux density FR being in a wavelength range of 700 nm or more and 780 nm or less.

The near-infrared luminescent material is capable of efficiently emitting near-infrared light with a peak wavelength of 900 nm to 1,100 nm under an effective excitation wavelength of 250 nm to 750 nm. The luminescent material has the characteristics of wide excitation emission wavelength, high luminous efficiency, uniform luminescence, no impurity phase, high stability, simple preparation and the like. The present invention further provides the light-emitting device prepared from the near-infrared luminescent material. The luminescent material and the light-emitting device provided by the present invention solve the problems of poor stability, low luminous efficiency, high preparation cost and the like of a conventional near-infrared luminescent material and light-emitting device, and have a favorable application prospect.

Examples of a monolithic phosphor composite for measuring a parameter of an object are disclosed. The composite comprises a thermographic phosphor and a metal oxide material that are dried and calcinated at high temperatures to form a ceramic metal oxide phosphor composite. The ceramic metal oxide phosphor composite is used in an optical device for measuring the parameter of the measuring object. The device comprises a fiber optic probe with a light guide, a light source operatively coupled to the fiber optic probe to provide excitation light into the light guide, a monolithic ceramic metal oxide phosphor composite functionally coupled to a tip of the fiber optic probe, a sensor operatively coupled to the fiber optic probe to detect the emitted light and a processing unit functionally coupled to the sensor to process the emitted light. When the monolithic ceramic metal oxide phosphor composite is illuminated with the excitation light it emits light in a wavelength different from the excitation light and a change in emission intensity at a single wavelength or the change in intensity ratio of two or more wavelengths, a shift in emission wavelength peak or a decay time of the phosphor luminescence is a function of the measuring parameter.

A process for ultrasensitive in vitro detection and/or quantification of a substance of interest in a sample is performed by detecting the luminescence emission by photoluminescent inorganic nanoparticles. The process includes (i) use of photoluminescent particles comprising a photoluminescent inorganic nanoparticle consisting of a crystalline matrix having at least 10.sup.3 rare-earth ions, and coupled to a targeting agent for the substance to be analyzed, under conditions conducive to their association with the sample substance to be analyzed; (ii) exciting the rare-earth ions of the particles by an illumination device having a power of at least 50 mW and an excitation intensity of at least 1 W/cm.sup.2; (iii) detecting the luminescence emission by the particles after single-photon absorption; and (iv) determining the presence and/or concentration of the substance by interpreting said luminescence measurement. This process can be used for in vitro diagnostic purposes and as an in vitro diagnostic kit.

An optical storage phosphor, a method for checking an authenticity feature, and an apparatus for carrying out a method, relate to an authenticity feature and to a value document. An inorganic optical storage phosphor is provided having a garnet structure and predetermined composition.

An object of the present invention is to provide an infrared light-emitting phosphor which emits light in a wavelength range where the sensitivity of a detector is high by combination with a semiconductor light-emitting element that emits light in the visible light region, and to provide an infrared light-emitting device using the infrared light-emitting phosphor. The object can be achieved with a light-emitting device including a semiconductor light-emitting element that emits ultraviolet light or visible light and a phosphor that absorbs ultraviolet light or visible light emitted from the semiconductor light-emitting element and emits light in the infrared region, wherein an emission peak wavelength in the infrared region of the phosphor emitting in the infrared region is from 750 to 1,050 nm, and the half width of an emission peak waveform is more than 50 nm.

Provided is a light emitting device that includes a light emitting element having a light emission peak wavelength ranging from 380 nm to 490 nm, and a fluorescent material excited by light from the light emitting element and emitting light having at a light emission peak wavelength ranging from 580 nm or more to less than 680 nm. The light emitting device emits light having a ratio R/B of a photon flux density R to a photon flux density B ranging from 2.0 to 4.0 and a ratio R/FR of the photon flux density R to a photon flux density FR ranging from 0.7 to 13.0, the photon flux density R being in a wavelength range of 620 nm or more and less than 700 nm, the photon flux density B being in a wavelength range of 380 nm or more and 490 nm or less, and the photon flux density FR being in a wavelength range of 700 nm or more and 780 nm or less.