Light-emitting device

Abstract

The invention relates to a light-emitting device, in particular to the structural improvement of a phosphor layer on a light-emitting diode chip. The light-emitting device comprises a substrate, the light-emitting diode chip and the phosphor layer, wherein the phosphor layer is provided with a first covering part and a second covering part; the first covering part is positioned on the top surface of the light-emitting diode chip; the second covering part covers the surface of the substrate around the light-emitting diode chip; height difference is formed between the top surface of the second covering part and the top surface of the first covering part. By the structural improvement of the phosphor layer, the color temperature difference value between the middle area and the edge area of the light-emitting device is reduced, and the light-emitting device has relatively high light-emitting quality.

Description

technical field [0001] The invention relates to a light-emitting device, in particular to a structural improvement of a fluorescent powder layer on a light-emitting diode chip. Background technique [0002] Light-emitting diodes (LEDs) have the advantages of low power consumption, long life, fast response, and small size. At present, the global white LED lighting industry continues to flourish, especially in mobile phone panel backlight, lighting and automotive industries. potential. [0003] At present, white light emitting devices on the market are mainly divided into two mainstreams. The first is to use phosphor to convert the blue light or ultraviolet light generated by blue LED or ultraviolet UV-LED into two-wavelength (Dichromatic) or three-wavelength (Trichromatic) white light, this technology is called phosphor powder conversion white light LED (Phosphor Converted-LED); the second type is a multi-chip white LED, which combines two (or more) LEDs of different colors...

AI Technical Summary

Problems solved by technology

[0009] another example figure 2 As shown, it is another traditional light-emitting device. The light-emitting diode chip 20 is arranged on the bottom of a reflective cup 40, and then the fluorescent powder colloid is coated on the top of the light-emitting diode chip 20 by dispensing. Phosphor powder layer 30 is formed in a limited space, however, due to flow, precipitation and surface tension of the phosphor powder colloid, the phosphor powder layer 30 will be convex in the middle, and the periphery will be sunken near the inner side of the reflective cup 40, resulting in the top of the light emitting diode chip 20. The thickness of the phosphor layer 30 is uneven, resulting in the yellow halo phenomenon of uneven color temperature when emitting light

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