Disclosed are a red light and near-infrared light-emitting material and a preparation method thereof, and a light-emitting device including the light-emitting material. The red light and near-infrared light-emitting material contains a compound represented by a molecular formula, aSc.sub.2O.sub.3.Math.Ga.sub.2O.sub.3.Math.bR.sub.2O.sub.3, wherein the element R includes one or two of Cr, Ni, Fe, Yb, Nd or Er; 0.001?a?0.6; and 0.001?b?0.1. The light-emitting material can be excited by a spectrum having a wide wavelength range (ultraviolet light or purple light or blue light) to emit light with a wide spectrum of 650 nm to 1700 nm or multiple spectra, thus having higher light-emitting intensity.

An optical device includes an LED chip, a visible-light luminescent material, and a near-infrared luminescent material, wherein a luminous power of light emitted by the near-infrared and visible-light luminescent materials in a band of 650-1000 nm under the excitation of the LED chip is A, and a sum of a luminous power of light emitted by the near-infrared and visible-light luminescent materials in a band of 350-650 nm under the excitation of the LED chip and a luminous power of residual light emitted by the LED chip in the band of 350-650 nm after the LED chip excites the near-infrared and visible-light luminescent materials is B, with B/A*100% being 0.1%-10%. According to the implementation where the optical device employs the LED chip to combine the near-infrared luminescent material and the visible-light luminescent material simultaneously.

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 present invention relates to a phosphor, a method for preparing the phosphor, an optoelectronic component, and a method for producing the optoelectronic component. The phosphor has the following general formula: La.sub.3(1x)Ga.sub.1yGe.sub.5(1z)O.sub.16: 3xA.sup.3+, yCr.sup.3+, 5zB.sup.4+, where x, y, and z do not equal to 0 simultaneously; A represents at least one of Gd and Yb; B represents at least one of Sn, Nb, and Ta. For the phosphor, its emission spectrum is within a red visible light region and a near-infrared region when excited by blue visible light, purple visible light or ultraviolet light; and it has a wide reflection spectrum and a high radiant flux. Therefore, it can be used in optoelectronic components such as LEDs to meet requirements of current medical testing, food composition analysis, security cameras, iris/facial recognition, virtual reality, gaming notebook and light detection and ranging applications.

Provided is a phosphor represented by general formula (1) below,

(Gd.sub.1-x-y,Ln.sub.y,M.sup.II.sub.x).sub.3M.sup.III.sub.2(Ga.sub.1-z,M.sup.IV.sub.z).sub.3O.sub.12:Cr.sup.3+(1) where, in the formula, Ln is one or more elements selected from La, Pr, Nd, Sm, Eu, Tb, Dy, Ho, Er, Yb, and Lu, M.sup.II is a divalent element, M.sup.III is a trivalent element, M.sup.IV is a tetravalent element, and x, y, and z satisfy 0<x<0.5, 0?y<0.5, and 0<z<0.5.

An infrared-excited infrared light emitting material and a preparation method thereof, and a security article for anti-counterfeit using thereof relate to a white to pale colored infrared-excited infrared light emitting material, a preparation method thereof, and an ink composition for anti-counterfeit containing the infrared exciting infrared light emitting material which visually appears white or colored, and is excited in the infrared region, emits light in the infrared region, but does not emit light in the visible region, and a security article requiring confirmation of authenticity and anti-counterfeit.

Disclosed is a light-emitting device provided with a solid-state light-emitting element and a phosphor and emits output light. The spectral distribution of the output light has a first light component and a second light component derived from fluorescence emitted by the phosphor, and has a first minimum value between the first light component and the second light component. The first light component is a fluorescent component having a maximum intensity value within a wavelength range of 560 nm or more and less than 700 nm. The second light component is a fluorescent component having a maximum intensity value within a wavelength range of 700 nm or more and less than 2500 nm. The maximum intensity value of the second light component is greater than that of the first light component. The first minimum value is less than 50% of the maximum intensity value of the second light component.

Provided is a light emitting device including a solid-state light-emitting element that emits primary light, a wavelength converter that includes a phosphor containing a fluorescent ion which absorbs the primary light on the basis of a forbidden transition-type electronic energy transition, and an optical member that reflects the primary light while transmitting fluorescence emitted by the fluorescent ion. The solid-state light-emitting element is arranged on a side of one surface of the wavelength converter and the optical member is arranged on a side of the other surface. The fluorescence emitted by the fluorescent ion passes through the optical member and is output to the outside of the light emitting device. An electronic apparatus includes the above-described light emitting device.

A security element has at least two luminescent substances, in which the security element has a first and a second luminescent substance which have a substantially identical, joint emission band. The first or the second luminescent substance, or both luminescent substances, have at least one excitation band that leads to an emission at the joint emission band only in the case of the first or the second luminescent substance.

The invention relates to a security element having at least two luminescent substances. The invention starts out from a security element having at least two luminescent substances, whereby the security element has a first and a second luminescent substance which have a substantially identical, joint emission band, whereby at least the first or the second luminescent substance, or both luminescent substances, have at least one excitation band that leads to an emission at the joint emission band only in the case of the first or the second luminescent substance.