Method for coating phosphor layer on light-emitting element and jetting device

Abstract

A method for coating a fluorescent powder layer onto a light-emitting element, and an air injection device. The method comprises: step A, dripping fluorescent powder slurry (2) onto a light-emitting surface (1a) of a light-emitting element (1), so that the fluorescent powder slurry (2) covers at least a partial area of the light-emitting surface (1a), and the surface of the fluorescent powder slurry (2) is in the shape of a curved surface; step B, conducting air injection on at least the partial area of the fluorescent powder slurry (2) on the light-emitting element (1), on which the fluorescent powder slurry (2) has been dripped, in a pre-set condition through a nozzle (10), so that the fluorescent powder slurry (2) covers the whole light-emitting surface (1a), and the fluorescent powder slurry (2) is laid more uniformly across the entire light-emitting surface (1a); and step C, solidifying the fluorescent powder slurry (2) to form a fluorescent powder sheet layer. The method of coating a fluorescent powder layer onto a light-emitting element (1) is intended to improve the uniformity of the thickness of the fluorescent powder layer across the entire light-emitting element (1).

Description

technical field [0001] The invention relates to the technical field of illumination and display, in particular to a method for coating a fluorescent powder layer on a light-emitting element and an air injection device. Background technique [0002] As a green and environment-friendly light source, white LED has achieved rapid development in recent years. One of the most commonly used methods for white LEDs is to use phosphor sheets to generate high-brightness color light. For example, a yellow phosphor layer can be formed on the surface of a blue LED, where the yellow phosphor is excited by blue light to produce yellow light. The light mixes with the blue light that is not absorbed to form white light. Therefore, as the core optical device of the light source, the manufacturing quality and efficiency of the phosphor sheet have an important impact on the final light source product. [0003] At present, there are many methods for coating phosphor powder on the surface of LED...

AI Technical Summary

Problems solved by technology

[0004] Because the surface of the phosphor paste is convex in an arc shape, the light-emitting surface of the phosphor LED becomes larger, which increases the etendue, resulting in low light efficiency.

At the same time, since the surface of the phosphor paste is not flat, the amount of blue light absorbed by the phosphor is different at different places on the light-emitting surface of the LED, resulting in poor color uniformity of the emitted white light.

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