A light source for emitting emitted light having an SPD comprising: (a) a plurality of light emitters including at least one violet solid-state emitter; (b) at least one phosphor; wherein said light emitters and said at least one phosphor being configured such that: at least 25% of the power within the SPD is in the range 390-420 nm, and the emitted light has a chromaticity which is within a Duv distance of less than 5 points from the Planckian locus.

Described herein is the application of centrifugal spinning to provide a flexible mechanoluminescent material composed of rare earth metal doped fibers. Rare earth metal doped fibers are formed, in one embodiment, by centrifugal spinning.

A light emitting device includes: a solid-state light emitting element that emits excitation light having a maximum intensity value within a wavelength range of 440 nm or more and less than 470 nm; and a wavelength conversion member composed by combining a first wavelength converter, which includes a first phosphor activated by Ce.sup.3+, and a second wavelength converter, which includes a second phosphor activated by Ce.sup.3+, with each other. The first phosphor emits first fluorescence having a maximum intensity value within a wavelength range of 470 nm or more and less than 530 nm, and the second phosphor emits second fluorescence having a maximum intensity value within a wavelength range of 580 nm or more and less than 660 nm. The first wavelength converter has a dispersed state in which particles of the first phosphor are not in contact with one another.

A light source for emitting emitted light having an SPD comprising: (a) a plurality of light emitters including at least one violet solid-state emitter; (b) at least one phosphor; wherein said light emitters and said at least one phosphor being configured such that: at least 25% of the power within the SPD is in the range 390-420 nm, and the emitted light has a chromaticity which is within a Duv distance of less than 5 points from the Planckian locus.

A light emitting device including a light emitting element for emitting blue light; and a fluorescent film including a single crystal fluorescent material or a polycrystalline fluorescent material, wherein the fluorescent film absorbs the blue light and emits light having a wavelength different from that of the blue light, wherein the fluorescent film faces a surface of the light emitting element, and the fluorescent material included in the fluorescent film is represented by the following Formula (1):

Y.sub.3-x-yL.sub.xM.sub.yAl.sub.5O.sub.12 wherein L is Gd or Lu, and M is Ce, Tb, Eu, Yb, Pr, Tm, or Sm, 0x2.999, and 0.001y0.1.

The present invention aims to provide a scintillator which has a short fluorescence decay time, whose fluorescence intensity after a period of time following radiation irradiation is low, and which shows largely improved light-transmittance. A scintillator represented by the following General Formula (1), the scintillator including Zr, having a Zr content of not less than 1500 ppm by mass therein, and being a block of a sintered body. Q.sub.xM.sub.yO.sub.3z:A . . . (1) (wherein in General Formula (1), Q includes at least one or more kinds of divalent metallic elements; M includes at least Hf; and x, y, and z independently satisfy 0.5?x?1.5, 0.5?y?1.5, and 0.7?z?1.5, respectively).

A light-emitting ceramic and a light-emitting device. The light-emitting ceramic comprises a YAG substrate and light-emitting centers and diffusion particles evenly dispersed in the YAG substrate. The light-emitting centers are lanthanide-doped YAG fluorescent powder particles of 10-20 m in grain size. The particle size of the scattering particles is 20-50 nm. The YAG substrate is a lanthanide-doped YAG ceramic. Also, the grain size of the YAG substrate is less than the grain size of the YAG fluorescent powder particles.

The present invention includes: a radiation detecting unit including a fluorescent body expressed by the formula ATaO.sub.4: B, C (in the formula, A is selected from at least one kind of element from among rare-earth elements involving 4f-4f transitions, B is selected from at least one kind of element, different from A, from among rare-earth elements involving 4f-4f transitions, and C is selected from at least one kind of element from among rare-earth elements involving 5d-4f transitions); an optical fiber that transmits photons generated by the fluorescent body; a light detector that converts the photons transmitted via the optical fiber 3 one by one into electrical pulse signals; a counter that counts the number of electrical pulse signals converted by the light detector; an analysis and display device 6 that obtains a radiation dose rate on the basis of the number of electrical pulse signals counted by the counter.

A boron nitride fluorescent material, having at least one light emission peak wavelength in a range of 480 nm or more and less than 650 nm as excited with light having a light emission peak wavelength in a range of 250 nm or more and 460 nm or less, and comprising: at least one element A selected from the group consisting of alkaline earth metal elements; nitrogen and boron; and optionally at least one element M1 selected from the group consisting of Tb, Sm, Pr, Ce, Mn, and Yb.

The present teachings relate to an endoscope (and methods of manufacturing the same) having an illumination system that utilizes small diameter fibers for delivering bright, high quality light to a target site. In accordance with one aspect, an endoscope is provided having a phosphor-loaded, light emitting distal tip that can be energized via optical radiation delivered to the light-emitting distal tip via a small-diameter optical fiber (e.g., less than about 100 m in diameter) that extends through or along the length of the endoscope. The light-emitting distal tip can be energized by short wavelength laser light (e.g., radiation having wavelengths at 445 nm blue or 405 nm violet) coupled to the optical fiber's proximal end so as to deliver light of extremely high quality CRI (e.g., greater than 80, greater than 90, about 95).