A kind of ultraviolet conversion white light LED transparent ceramic material and preparation method thereof

Abstract

The invention relates to an ultraviolet conversion white light LED transparent ceramic material and a preparation method thereof. Chemical formula of the transparent ceramic material is [R(1-x-y)Dy(x)Tm(y)](3)Al(5)O(12), wherein R is used for representing one or two elements selected from Lu, Y, and Yb; x and y are used for representing molar coefficients, 0.005<=x<=0.15, and 0<=y<=0.04; the transparent ceramic material is capable of emitting white light under excitation of ultraviolet LED chips. The transparent ceramic material possesses following obvious advantages, firstly, the transparent ceramic material is used for replacing conventional resin packaged fluorescent particles, so that luminescence uniformity is increased; and in addition, thermal conductivity and high temperature stability of the transparent ceramic material are better than that of resin, so that service life of LED devices are prolonged greatly; secondly, ultraviolet sources are adopted, so that influences of excitation light sources on white light chromaticity are reduced to a great extent. The ultraviolet conversion white light LED transparent ceramic material is prepared via vacuum reaction sintering; optical transmitance of ceramic at visible band is high; the preparation method is simple; large size preparation can be realized; stability is high; and the ultraviolet conversion white light LED transparent ceramic material is especially suitable for large power white light LED devices.

Description

technical field [0001] The invention relates to an ultraviolet conversion white light LED transparent ceramic material and a preparation method thereof, in particular to a transparent ceramic material capable of absorbing and converting ultraviolet light and a preparation method thereof, belonging to the technical field of LED lighting. Background technique [0002] As a new type of lighting source, white LED has significant advantages such as energy saving, environmental protection, non-toxic, non-polluting, and long service life compared with traditional incandescent and fluorescent lamps. Especially in terms of reducing energy consumption and environmental decompression, the promotion and application of white light LEDs have played a huge role. In the United States, 22% of electricity is used for lighting. If all lighting sources are replaced by LEDs, 1000TW h can be saved every year, which is equivalent to the annual power generation of 230 500MW coal power stations, an...

AI Technical Summary

Problems solved by technology

This technology has some obvious shortcomings: the light emitted by the excitation light source is a component of white light, which is greatly affected by current and voltage, which reduces the stability of white light; resin is used as a packaging material, and it is difficult to ensure the dispersion of phosphor powder. The uniformity of the packaging process is complicated; the lack of red light in the emission spectrum leads to a low color rendering index of the white LED produced; the blue light is irritating to the human eye and easily causes discomfort, so it is difficult to be widely used in the lighting field; Low thermal conductivity, easy aging in high temperature environment, and the luminous efficiency of phosphor decays rapidly with the increase of temperature, resulting in unstable white light quality and reduced lifespan

Although this patent replaces the resin encapsulation material with a bulk transparent ceramic with high thermal conductivity, although the thermal stability is improved and the service life of the LED device is effectively extended, the white light obtained through blue light excitation also has low color rendering index and low white light stability. Human eye irritation and other defects

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