Abstract:
A tanning device is described by which the bluish light emitted by mercury vapor lamps is converted into yellow or white light. For this purpose, the mercury lamps, or the sheets of transparent plastics material covering these lamps, are doped or coated with one or more organic or inorganic fluorescent dyes that partially absorb the blue light emitted by the mercury lamps and convert it into light of wavelengths of 550 to 650 nm.
Abstract:
A luminescent material is dispersed in a watery solution of sodium polyphosphate, a watery solution of a nitrate of the metal M is added, after which the luminescent material is separated, dried and fired. The metal is chosen from the group consisting of Ca, Sr, and Ba, whereby a protective layer of metal polyphosphate is formed on the luminescent material.
Abstract:
A gas discharge lamp has a gas discharge vessel filled with a gas filling suitable for a gas discharge which emits VUV radiation, with a phosphor coating containing a downconversion phosphor. The downconversion phosphor has, in a host lattice, a pair of activators of a first lanthanoid ion and a second lanthanoid ion; a sensitizer selected from the group formed by the thallium(I) ion, lead(II) ion and bismuth(III) ion; and samarium(II) ion co-activator.
Abstract:
A lighting system includes at least two light-emitting diodes each emitting, in operation, visible light in a preselected wavelength range. A converter converts part of the visible light emitted by one of the diodes into visible light in a further wavelength range so as to optimize the color rendition of the lighting system. The diodes include a blue light-emitting diode and a red light-emitting diode. Further, the converter includes a luminescent material for converting a portion of the light emitted by the blue light-emitting diode into green light.
Abstract:
A lamp vessel is made from a material which absorbs short-wave UV radiation. In addition, the luminescent screen comprises cerium-activated lunthanum phosphate and a luminescent substance having an emission band whose maximum is situated in the wavelength range from 340 nm and whose half-value ranges between 35 nm and 80 nm. The emission spectrum of the lamp for wavelengths below 400 nm corresponds closely to the solar spectrum while the lamp also has a high erythema L light output.
Abstract:
A lighting system includes at least two light-emitting diodes each emitting, in operation, visible light in a preselected wavelength range. A converter converts part of the visible light emitted by one of the diodes into visible light in a further wavelength range so as to optimize the color rendition of the lighting system. The diodes include a blue light-emitting diode and a red light-emitting diode. Further, the converter includes a luminescent material for converting a portion of the light emitted by the blue light-emitting diode into green light.
Abstract:
The invention relates to a light emitting device (1) with high colour rendering comprising a wavelength converting member (2) with a luminescent medium for wavelength conversion of blue light and/or ultraviolet light (10) into red light and/or yellow and/or green light and a light source (3) emitting blue light (10) and/or ultraviolet light arranged to pump the luminescent medium, said luminescent medium essentially having a main phase of a solid state host material which is doped with Ce3+-ions. According to the invention the host material comprises ions of a further rare-earth material Ln, wherein the host material is selected such that the emission energy of the 5d-4f emission on Ce3+-ions is energetically higher than the absorption energy into an upper 4fn state of the further rare-earth material Ln, and wherein the light emission of wavelength converted light is caused by an intra-atomic 4fn- 4fn transition within the ions of the further rare-earth material. The invention further relates to a corresponding lighting system comprising the light-emitting device and a corresponding luminescent medium.
Abstract:
A vehicle position measurement system (100) and method to determine the (relative) position of a vehicle (110) and an object (120) are proposed. The system comprises at least two light sources (131, 132) capable of emitting light and positioned at a predetermined distance (140) to each other. Furthermore the system comprises at least one detector (150 / 151, 152) capable of measuring the light emitted. The light emitted by the light sources comprises synchronized light source identification codes. The detector is arranged to determine the position of the vehicle (110) and object (120) on the basis of a phase-difference measurement between the light originating from the individual light sources (131, 132) and a comparison phase. The vehicle (110) may comprise the at least two light sources (131, 132) and the detector (151, 152), while the phase-difference is measured between light reflected from the object (120) and the comparison phase. Alternatively, the vehicle (110) may comprise the at least two light sources (131, 132) while the object (120) comprises the detector (150) and the detector is arranged to obtain the comparison phase from the light received from one of the light sources (131, 132). The object may be a vehicle.
Abstract:
A hot axial pressing method for sintering a ceramic powder, particularly doped Gd2O2S, comprise the step of placing a first porous body (7), the ceramic powder (9) and a second porous body (7) into a mould shell (5) supported by a support (13, 14). The ceramic powder (9) is located between the porous bodies (7). Gaseous components are evacuated from the ceramic powder (9) up to an ambient pressure of less than 0,8 bar. The porous body (7) and the ceramic powder (9) are heated to a maximum temperature of at least 900° C and are applied to a pressure up to a maximum pressure of at least 75 Mpa. According to the invention the variation in time of the heating step and the variation in time of the pressure applying step is adjusted to each other such that the mould shell 5 is held by the porous bodies (7) and/or the ceramic powder (9) in a state where the mould shell (5) and the support (13, 14) are disconnected with respect to each other.
Abstract:
A radiation- sensitive detector includes a photosensor elements (122) and a scintillator (116) optically coupled to the photosensor element (122). The scintillator (116) includes a powdered scintillator and a resin mixed with the powdered scintillator. The refractive index mismatch between the powdered scintillator and the resin is less than 7%. In one non-limiting instance, the composite scintillator material may be used to form fiber optic leaves arranged as a high-resolution detector array in conventional or spectral CT.