CN106356439A - An LED packaging structure with adjustable color temperature - Google Patents

Abstract

The invention discloses a color temperature adjustable LED packaging structure which comprises a packaging substrate and LED chips arranged on the packaging substrate, wherein the LED chips comprise a first LED chip and a second LED chip, the upper end surface of the first LED chip is covered with a first fluorescent layer, the LED packaging structure is also provided with a second fluorescent layer covered on the packaging substrate and the second LED chip, and the color temperatures of the first fluorescent layer and the second fluorescent layer are different. The light emitted by the first LED chip and the light emitted by the second LED chip are white light after passing through the primary fluorescent layer, so that the problems of light bias and light quality reduction are solved; the first LED chips and the second LED chips are uniformly and alternately arranged on the packaging substrate, the side surfaces of the bottoms of the first LED chips and the second LED chips are wrapped by the second fluorescent layer, the phenomenon that the light quality is reduced due to the fact that blue light of the first LED chips and the blue light of the second LED chips are leaked is avoided, uniform light is obtained, and the light spot effect when only one LED chip is used is eliminated.

Description

An LED packaging structure with adjustable color temperature

technical field

The invention belongs to the field of LED packaging, in particular to an LED packaging structure with adjustable color temperature.

Background technique

The method of manufacturing white light LED chips is: directly cover a layer of fluorescent film on the blue LED wafers with electrode pads prepared in advance, and form individual white light LED chips after cutting. The problem is: white light LED chips There will be blue light leakage on the bottom side of the , causing light quality defects. When using LED chips to manufacture LED light sources, in order to realize the adjustable color temperature of the LED light source, the commonly used technical means are to arrange the packaged LED chip unit and a bare LED chip unit formed by the first fluorescent layer in advance on the packaging substrate. A second fluorescent layer is also provided to cover the above-mentioned wrapped LED chip unit and a bare LED chip unit. The LED light source with this packaging structure achieves light color consistency, uniform light, and adjustable color temperature, but the manufacturing process of the wrapped LED chip unit is complicated, and the light emitted from the top and side of the chip is white light, making the wrapped LED chip After the white light emitted by the unit passes through the fluorescent powder in the middle of the second fluorescent layer again, it will emit a yellowish or greenish mixed color light), which reduces the light quality and causes discomfort to users.

Contents of the invention

The LED packaging structure with adjustable color temperature provided by the present invention can effectively solve the technical problems of polarization and light quality degradation after the light passes through the fluorescent layer for the second time. The technical solution adopted in the present invention is:

An LED packaging structure with adjustable color temperature, comprising a packaging substrate and an LED chip arranged on the packaging substrate, the LED chip includes a first LED chip and a second LED chip, and the upper end surface of the first LED chip is covered with The first fluorescent layer is also provided with a second fluorescent layer covering the packaging substrate and the second LED chip, wherein the first fluorescent layer and the second fluorescent layer have different color temperatures.

Further, the first LED chips and the second LED chips are evenly arranged in a staggered manner on the packaging substrate.

Further, the distance between the first LED chip and the second LED chip is not greater than twice the size of the first LED chip or the second LED chip.

Further, the height of the second fluorescent layer on the packaging substrate is not lower than the height of the first LED chip on the packaging substrate.

Further, the first fluorescent layer and the second fluorescent layer have the same thickness on the package substrate.

Further, the thickness of the second fluorescent layer on the packaging substrate is not higher than the thickness of the first fluorescent layer on the packaging substrate.

According to the present invention, the light emitted from the upper end surface of the first LED chip passes through the first fluorescent layer and emits white light. The side of the first LED chip is surrounded by the second fluorescent layer, and the light emitted from the side of the first LED chip passes through the second fluorescent layer. White light with different color temperatures can be obtained after layering, and the light emitted by the second LED chip passes through the second fluorescent layer and emits white light; avoiding the first LED chip and the second LED chip from passing through the fluorescent layer twice, solving the problem The problem of light quality degradation caused by polarized light; the sides of the bottom of the first LED chip and the second LED chip are wrapped by the second fluorescent layer, and the second fluorescent layer around the first LED chip protects the first LED chip. function, to avoid the problem of light leakage from the side of the bottom of the first LED chip and the second LED chip; the first LED chip and the second LED chip are evenly arranged in a staggered manner, and the emitted light is mixed to obtain uniform light, eliminating the need for only one on the packaging substrate. The light spot effect when planting LED chips.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only For some embodiments of the present invention, those skilled in the art can also obtain other drawings based on these drawings without creative work.

1 is a schematic diagram of the basic layout of the LED packaging structure with adjustable color temperature according to the present invention;

Fig. 2 is the structural representation of the COB adopting the LED packaging structure with adjustable color temperature according to the present invention;

Fig. 3 is a schematic structural diagram of an SMD adopting the LED packaging structure with adjustable color temperature according to the present invention.

detailed description

In order to make the purpose, technical solutions and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention and the accompanying drawings.

The specific implementation manner of the present invention will be described below in conjunction with the accompanying drawings.

As shown in FIG. 1 , the LED packaging structure with adjustable color temperature in the present invention includes a packaging substrate 1 and an LED chip 2 disposed on the packaging substrate 1 . The LED chip 2 includes a first LED chip 21 and a second LED chip 22, and the first LED chip 21 and the second LED chip 22 are evenly arranged alternately on the packaging substrate 1, and the first LED chip 21 and the second LED chip The distance between 22 is not more than twice the size of the first LED chip 21 or the second LED chip 22, the emitted light has the same color and uniform light mixing, and uniform white light is obtained.

The upper surface of the first LED chip 21 is covered with the first fluorescent layer 3, and the LED chip 22 and the package substrate 1 are covered with the second fluorescent layer 4, wherein the first fluorescent layer 3 and the second fluorescent layer The color temperatures of the layers 4 are different, and the height of the second fluorescent layer 4 on the packaging substrate 1 is not lower than the height of the first LED chip 21 on the packaging substrate 1 . Preferably, the thicknesses of the first phosphor layer 3 and the second phosphor layer 4 on the package substrate 1 are equal.

The materials of the first fluorescent layer 3 and the second fluorescent layer 4 are formed by mixing transparent silica gel and fluorescent powder, and the concentrations of the fluorescent powder in the transparent silica gel in the first fluorescent layer 3 and the second fluorescent layer 4 are different, and the obtained The color temperatures of the first fluorescent layer 3 and the second fluorescent layer 4 are different.

The upper surface of the first LED chip 21 is only covered with the first fluorescent layer 3, the light emitted upward by the first LED chip 21 passes through the first fluorescent layer 3 and emits white light, and the light emitted from the side of the first LED chip 21 passes through the second fluorescent layer 4. Then emit white light. The white light emitted upward by the first LED chip 21 and the white light emitted from the side have different color temperatures. The white light of the two color temperatures can be mixed to obtain white light of another color temperature, which eliminates the problem of only one LED chip. Light spot effect, with better lighting effect.

Only the second fluorescent layer 4 is coated on the second LED chip 22, and the light emitted by the second LED chip 22 emits white light after passing through the second fluorescent layer 4, so as to prevent the light emitted by the first LED chip 21 and the second LED chip 22 from being caused by The second pass through the fluorescent layer results in a color cast and a decrease in light quality.

Example 1

As shown in Figure 2, Embodiment 1 is a COB with adjustable color temperature using the LED packaging structure of the present invention, including a COB substrate 5, a first LED chip 21 and a second LED chip 22 arranged on the COB substrate 5, so The upper end surface of the first LED chip 21 is covered with a first fluorescent layer 3 (not shown in the figure), and the second fluorescent layer 4 is covered on the COB substrate 5 and the second LED chip 22, wherein the first fluorescent layer 3 and the second fluorescent layer 4 have the same thickness on the COB substrate 5, and the first fluorescent layer 3 and the second fluorescent layer 4 are made of different fluorescent materials and have different color temperatures. When the first LED chip 21 and the second LED chip 22 are turned on, the light emitted upward by the first LED chip 21 passes through the first fluorescent layer 3 and becomes white light, and the light on the bottom side of the first LED chip 21 and the second LED The chip 22 becomes white light with different color temperatures after passing through the second fluorescent layer 4 , and emits two kinds of white light with different color temperatures.

The first LED chips 21 and the second LED chips 22 are evenly arranged in a staggered manner on the COB substrate 5, and the distance between the first LED chips 21 and the second LED chips 22 is twice that of the LED chips 2, and the distance Small, so that the light emitted by the first LED chip 21 and the second LED chip 22 mixes and produces uniform light, and can be adjusted separately by controlling the first LED chip 21 and the second LED chip 22 to have their own independent driving signals. The intensity of the driving signal is used to adjust the color temperature output ratio of the first LED chip 21 and the second LED chip 22, so as to obtain a COB with adjustable color temperature.

Example 2

As shown in Figure 3, Embodiment 2 is an SMD with adjustable color temperature using the LED package structure of the present invention, including an LED bracket 6, and a first LED chip 21 and a second LED chip 22 arranged on the LED bracket 6, so The first LED chip 21 is covered with a first fluorescent layer 3, and a second fluorescent layer 4 for covering the second LED chip 22 and filling the groove of the LED bracket 6 is also provided, wherein the first fluorescent layer 3 and the second The thickness of the fluorescent layer 4 is different, and the heights of the first fluorescent layer 3 and the second fluorescent layer 4 on the LED bracket 6 are equal.

In this embodiment, the first LED chip 21 and the second LED chip 22 are respectively connected to different driving circuits on the LED bracket 6, and different driving signals are input to the first LED chip 21 and the second LED chip 22 to obtain an adjustable light color. SMD.

It should be noted that the described embodiments are only some of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

Claims (5)

1. An LED packaging structure with adjustable color temperature, comprising a packaging substrate and an LED chip arranged on the packaging substrate, wherein the LED chip comprises a first LED chip and a second LED chip, and the first LED The upper surface of the chip is covered with a first fluorescent layer, and a second fluorescent layer is provided covering the packaging substrate and the second LED chip, wherein the first fluorescent layer and the second fluorescent layer have different color temperatures. 2 . The LED packaging structure with adjustable color temperature according to claim 1 , wherein the first LED chips and the second LED chips are evenly arranged in a staggered manner on the packaging substrate. 3. The LED packaging structure with adjustable color temperature according to claim 2, wherein the distance between the first LED chip and the second LED chip is not greater than the size of the first LED chip or the second LED chip twice as much. 4 . The LED packaging structure with adjustable color temperature according to claim 1 , wherein the height of the second fluorescent layer on the packaging substrate is not lower than the height of the first LED chip on the packaging substrate. 5 . The LED packaging structure with adjustable color temperature according to claim 1 , wherein the first fluorescent layer and the second fluorescent layer have the same thickness on the packaging substrate.