CN102376832A - white light emitting diode - Google Patents

Abstract

A white light LED comprises an LED chip, which comprises a first light-emitting region and a second light-emitting region, and at least two currents are respectively conducted, wherein the LED chip emits a blue light; a first wavelength conversion layer arranged on the first light-emitting interval, wherein the first wavelength conversion layer is excited by blue light to generate first conversion light, and the first conversion light is mixed with the blue light to form warm white light; a second wavelength conversion layer arranged on the second light-emitting interval, wherein the second wavelength conversion layer is excited by blue light to generate second conversion light, and the second conversion light is mixed with the blue light to form cold white light; by controlling the current amount of the currents, the luminous intensity of each luminous interval is adjusted, and the adjustment of the color temperature of the white light emitting diode is achieved.

Description

white light emitting diode

technical field

The invention relates to a white light emitting diode, in particular to a white light emitting diode with different color temperatures to achieve dimming function.

Background technique

A light emitting diode (Light Emitted Diode, LED) is a semiconductor component that mainly converts electrical energy into light energy through semiconductor compounds to achieve the effect of light emission. Therefore, it has the characteristics of long life, high stability and low power consumption. In the early days, it was mainly used as lights for indicator lights, traffic signals or signboards. With the emergence of white light-emitting diodes, it began to be used in lighting equipment.

The traditional manufacturing method of white light-emitting diodes is to coat yellow Yttrium Aluminum Garnet (YAG) phosphor powder on the chip of blue light-emitting diodes. When the yellow phosphor powder is excited by blue light, the yellow light produced by it and The blue light originally used for excitation is mixed to produce white light.

However, due to the blue light emitting diode chip and the white light emitting diode made of the yellow phosphor, the blue light accounts for most of the spectrum, so there will be high color temperature and uneven light mixing.

In addition, some manufacturers mix the above-mentioned white light emitting diodes with red light emitting diodes or green light emitting diodes to form a light source module, so as to neutralize the problem of high color temperature of the white light emitting diodes. However, because the light-emitting diodes of individual colors are made of different materials, their driving voltages are also different, resulting in increased difficulty in circuit design; and the temperature characteristics and lifespan of light-emitting diodes of individual colors are not the same, making different light source modules There are also differences in light color and service cycle, which causes inconvenience in use.

Contents of the invention

In view of the prior art, in order to solve the problems of high color temperature of traditional white light-emitting diodes, uneven light mixing, and poor convenience in use, an object of the present invention is to provide a white light that can simultaneously generate different color temperatures, and A white LED that mixes these white lights to adjust the color temperature.

To achieve the above object, the present invention provides a white light emitting diode, which includes a light emitting diode chip, a first wavelength conversion layer and a second wavelength conversion layer.

The light-emitting diode chip includes a first light-emitting interval and a second light-emitting interval. The first light-emitting interval and the second light-emitting interval are respectively conducted with at least two currents, and the light-emitting diode chip emits a blue light.

The first wavelength conversion layer is arranged on the first light-emitting region, and the first wavelength conversion layer is excited by the blue light to generate a first converted light, and the first converted light is mixed with the blue light to form a warm white light.

The second wavelength conversion layer is arranged on the second light-emitting region, and the second wavelength conversion layer is excited by the blue light to generate a second converted light, and the second converted light is mixed with the blue light to form a cool white light; by controlling The current amounts of these currents are used to adjust the luminous intensity of each luminous interval and achieve the adjustment of the color temperature of the white light emitting diode.

The effect of the present invention is that the white light emitting diode of the present invention divides a light emitting diode chip into at least two sections, and different wavelength conversion layers are coated on different sections, so that these sections simultaneously generate white light with different color temperatures, and then The adjustment of the color temperature of the white light emitting diode is achieved by mixing the white lights with different color temperatures. The overall preparation process is simple, and effectively solves the problems of unequal service life of the light-emitting diodes and complicated circuit design caused by different driving voltages caused by using light-colored light-emitting diodes to adjust the color temperature.

The present invention will be described in detail below in conjunction with the accompanying drawings and specific embodiments, but not as a limitation of the present invention.

Description of drawings

1 is a top view of a white light emitting diode according to a first embodiment of the present invention;

2 is a cross-sectional view of a white light emitting diode according to a first embodiment of the present invention;

Fig. 3 is the top view of the electrode connection mode of the LED chip of the present invention;

Fig. 4 is the sectional view of the electrode connection mode of the LED chip of the present invention;

5 is a top view of a white light emitting diode according to a second embodiment of the present invention; and

FIG. 6 is a color temperature coordinate diagram.

Among them, reference signs

1 white light emitting diode

10 blue LED chips

12 The first luminous interval

14 Second luminous interval

100 light units

102 conductive unit

20 The first wavelength conversion layer

30 second wavelength conversion layer

Lc warm white light

Lw cool white light

Detailed ways

Below in conjunction with accompanying drawing, structural principle and working principle of the present invention are specifically described:

Referring to FIG. 1 and FIG. 2 together, they are respectively a top view and a cross-sectional view of a white light emitting diode according to a first embodiment of the present invention. The white light emitting diode 1 includes a blue light emitting diode chip 10 , a first wavelength conversion layer 20 , and a second wavelength conversion layer 30 .

The blue light emitting diode chip 10 emits a blue light, the blue light emitting diode chip 10 includes a first light emitting region 12 and a second light emitting region 14, and the first light emitting region 12 conducts a first current I ₁ , the second light emitting region The light-emitting interval 14 conducts a second current I ₂ . In this embodiment, the blue LED chip 10 includes sixteen light emitting units 100 arranged in a matrix, the first light emitting section 12 and the second light emitting section 14 respectively include eight light emitting units 100 connected in series, But in actual use, it is not limited to this.

Referring to FIG. 3 and FIG. 4 together, it is a top view and a cross-sectional view of the electrode connection method of the white light emitting diode of the present invention. The first light-emitting area 12 and the second light-emitting area 14 respectively include a plurality of light-emitting units 100, and each of the light-emitting units 100 is connected in series by using a conductive unit 102. They are connected in series so that the currents passing through the light emitting units 100 are all equal.

Referring again to FIG. 1 and FIG. 2, the first wavelength conversion layer 20 is disposed in the first light-emitting region 12. The first wavelength conversion layer 20 includes yellow photoluminescence phosphor and red photoluminescence phosphor, which can absorb short wavelengths. blue light and emit longer wavelength light. When the first light-emitting region 12 is conducted with the first current _I1 , the first wavelength conversion layer 20 disposed in the first light-emitting region 12 is excited by blue light to generate a first converted light L1, and the first converted The light L1 is mixed with the blue light to form a warm white light Lw, wherein the warm white light refers to a color temperature range from 2670K to 3800K.

The second wavelength conversion layer 30 is disposed in the second light-emitting region 14 , and the second wavelength conversion layer 30 includes yellow photoluminescence phosphor. When the second current _I2 is conducted in the second light-emitting region 14, the second wavelength conversion layer 30 disposed in the second light-emitting region 14 is excited by blue light to generate a second converted light L2, and the second converted The light L2 is mixed with the blue light to form a cool white light Lc, wherein the cool white light refers to a color temperature range from 5000K to 10000K.

When the first light-emitting interval 12 and the second light-emitting interval 14 are simultaneously conducted with the first current _I1 and the second current _I2 , a mixture of the first light-emitting interval 12 and the second light-emitting interval 14 is generated. The neutral white light of the warm white light Lw and the cool white light Lc, wherein the neutral white light refers to a color temperature range of 3800K to 5000K.

In addition, when the number of light-emitting units 100 in the first light-emitting interval 12 is equal to the number of light-emitting units 100 in the second light-emitting interval 14, by controlling the second light-emitting interval 12 and the second light-emitting interval 14 The magnitude of the current _I1 and the second current _I2 can also achieve the function of controlling the color temperature of the white light emitting diode 1 , wherein the magnitude of the current is proportional to the light intensity of the light emitted in the light-emitting interval. When the current amount of the first current _I1 is equal to the current amount of the second current _I2 , the light intensity of the warm white light Lw is equal to the light intensity of the cool white light Lc, and the white light emitting diode 1 emits a neutral white light; When the first current _I1 is greater than the second current _I2 , the light intensity of the warm white light Lw is greater than the light intensity of the cool white light Lc, and the white light emitting diode 1 emits a warm white neutral white light, Or when the second current _I2 is zero, the white light emitting diode 1 emits a warm white light; when the first current _I1 is less than the second current _I2 , the light intensity of the warm white light Lw is less than that of the cold light. For the light intensity of the white light Lc, the white light emitting diode 1 emits a cool white neutral white light, or when the first current _I1 is zero, the white light emitting diode 1 emits a cool white light.

Referring to FIG. 5 , it is a top view of a white light emitting diode according to a second embodiment of the present invention. The biggest difference between the white light emitting diodes of this embodiment and the white light emitting diodes of the above embodiments lies in the distribution of the light emitting regions 12 of the blue light emitting diode chip 10 . In this embodiment, the first light-emitting interval 12 and the second light-emitting interval 14 of the blue light-emitting diode chip 10 are set in a staggered manner, and the first wavelength conversion is set corresponding to the first light-emitting interval 12 and the second light-emitting interval 14. Layer 20 and the second wavelength converting layer 30. When the first light-emitting interval 12 and the second light-emitting interval are respectively conducted with the first current _I1 and the second current _I2 , the first light-emitting interval 12 and the second light-emitting interval 14 will generate the warm white correspondingly. The light Lw and the cool white light Lc, and the warm white light Lw and the cool white light Lc generated by the first light emitting region 12 and the second light emitting region 14 are mixed to generate neutral white light. In particular, since the first light-emitting intervals 12 and the second light-emitting intervals 14 are arranged alternately, the uniformity of the mixed neutral white light is greatly improved.

Referring to FIG. 6 , it is a color temperature coordinate diagram. The color temperature coordinate diagram shows the positions of color temperature 6000K, color temperature 4000K and color temperature 3000K respectively, where the color temperature of 6000K is cool white light, the color temperature of 4000K is neutral white light, and the color temperature of 3000K is warm white light.

The following table is the measurement data of the white light emitting diode of the present invention. In this embodiment, the white light emitting diode includes six light emitting units arranged in a matrix, and the first light emitting section and the second light emitting section respectively include three series connected The light-emitting unit 100, wherein the first light-emitting interval and the second light-emitting interval flow through the first current and the second current respectively, and the current amount of the first current is equal to the current amount of the second current, so that the six emitters can emit Lighting units with different color temperatures are measured. Numbers 1 to 6 are for measuring the color temperature of the above six light emitting units. The X and Y coordinates of the light-emitting units numbered 1, 2, and 3 in the table are (0.3263, 0.3397), (0.3266, 0.3394), (0.3263, 0.3398), and their coordinate positions correspond to the color temperatures of 6021K, 5980K, and 6051K, respectively. Cool white light. The X and Y coordinates of the light-emitting units numbered 4, 5, and 6 in the table are (0.4404, 0.4160), (0.4410, 0.4150), (0.4422, 0.4162), and their coordinate positions correspond to the color temperatures of 3012K, 2990K, and 2982K, respectively, for sending out Warm white light. Number 7 in the table is the mixed light measurement data of the white light emitting diode composed of six light emitting units with different color temperatures. The color temperature is 4108K for emitting a neutral white light.

serial number X-axis coordinate position Y-axis coordinate position Color temperature (K) 1 0.3263 0.3397 6021 2 0.3266 0.3394 5980 3 0.3263 0.3398 6051 4 0.4404 0.4160 3012 5 0.4410 0.4150 2990 6 0.4422 0.4162 2982 7 0.3752 0.3733 4108

Based on the above, the white light emitting diode of the present invention divides a blue light emitting diode chip into at least two sections, and coats different wavelength conversion layers in different sections, so that at least two currents pass through these sections, and these currents are used According to the magnitude of the current, these intervals are selectively turned on to generate white light with different color temperatures at the same time, and then by mixing the white lights with different color temperatures, the color temperature of the white light-emitting diode can be adjusted to increase its dimming performance. The overall preparation process of the present invention is simple and convenient, and effectively solves the problems of unequal service life of light-emitting diodes and complicated circuit design caused by different driving voltages caused by using light-colored light-emitting diodes to adjust color temperature.

Certainly, the present invention also can have other multiple embodiments, without departing from the spirit and essence of the present invention, those skilled in the art can make various corresponding changes and deformations according to the present invention, but these corresponding Changes and deformations should belong to the scope of protection of the appended claims of the present invention.

Claims (10)

1. a white light emitting diode is characterized in that, comprises:

One light-emitting diode chip for backlight unit, its comprise between one first luminous zone and one second luminous zone between, between this first luminous zone and between this second luminous zone respectively conducting at least two electric currents are arranged, wherein this light-emitting diode chip for backlight unit sends a blue light;

One first wavelength conversion layer, be arranged between this first luminous zone on, this first wavelength conversion layer receives blue-light excited back to produce one first conversion light, this first conversion light also becomes a warm white line with the blue light mixed light; And

One second wavelength conversion layer; On being arranged between this second luminous zone, this second wavelength conversion layer receives blue-light excited back to produce one second conversion light, and this second conversion light also becomes a cold white light line with the blue light mixed light; Wherein, By the magnitude of current of those electric currents of control,, and reach the adjustment of white light emitting diode colour temperature with the adjustment luminous intensity between this luminous zone respectively.

2. white light emitting diode according to claim 1 is characterized in that, those electric currents include one first electric current and one second electric current.

3. white light emitting diode according to claim 1 is characterized in that, this first wavelength conversion layer includes yellow photoluminescent phosphor and red photoluminescent phosphor.

4. white light emitting diode according to claim 1 is characterized in that, this second wavelength conversion layer includes yellow photoluminescent phosphor.

5. white light emitting diode according to claim 1 is characterized in that, comprises a plurality of luminescence units respectively between between this first luminous zone and this second luminous zone.

6. white light emitting diode according to claim 5 is characterized in that, the luminescence unit number that comprises between between this first luminous zone and this second luminous zone is identical.

7. white light emitting diode according to claim 6 is characterized in that, this first electric current equals this second electric current, and this white light emitting diode sends neutral white light.

8. white light emitting diode according to claim 3 is characterized in that respectively this luminescence unit is for being connected in series.

9. white light emitting diode according to claim 3 is characterized in that those luminescence units are arrayed.

10. white light emitting diode according to claim 1 is characterized in that, those luminescence unit interleaved are provided with.

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