KR101524968B1 - Green phosphor for high color reproducing uv-led back-light-unit, and method of designing composition thereof - Google Patents

Abstract

The present invention relates to gosaek reproduced UV-LED light unit green phosphor and their composition design method for, more specifically, BaMgAl ₁₀ O _17: Eu, the Mn phosphor Eu, or UV-LED through the content control of Mn This is a method of controlling the saturation phenomenon during high current driving. By controlling the amount of Eu and Mn added to the green phosphor BaMgAl ₁₀ O ₁₇ : Eu and Mn through the present invention, it is possible to improve the luminance saturation phenomenon caused by increasing the LED PKG current, It is possible to apply the green phosphor for reproduction UV-LED BLU, thus realizing the premium LED BLU.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a green phosphor for a color reproduction UV-LED backlight unit and a method for designing the green phosphor,

The present invention relates to a green phosphor for a high color reproduction UV-LED backlight unit and a method for designing the composition thereof.

The combination of blue LED PKG in LED BLU is a combination of blue LED with green and red phosphors. The color recall rate is determined by the color coordinates of blue, green, and red that pass through the color filter, and what percentage of the NTSC color coordinates correspond to the area is referred to as the color recall rate.

One of the important factors that determines the color reproduction rate in BLU is the combination of phosphors. Currently, Blue LED, LSN (Yellow Phosphor) and SCASN (Red Phosphor) are applied to common blue LED BLU, resulting in a color recall rate of about 70%, which is limited in the application of premium grade.

In order to solve this problem, studies have been made to improve the color reproduction ratio with a green phosphor having a center wavelength of 510 to 530 nm and a narrow half width.

However, Blue LED PKG has a limit in achieving color reproduction rate of 85% or more. The development of UV-LED is progressing to realize color recall rate of 85% or more. In the case of UV-LED Green phosphor, BaMgAl ₁₀ O ₁₇ : Eu, Mn is under development. The center wavelength of 515nm and the narrow half width (25nm) make it possible to realize a color reproduction rate of 85% or more, so that a high color reproduction can be applied.

However, when UV-LED PKG is driven at high current, the application of UV-LED BLU is limited by luminance saturation due to different decay time of BaMgAl ₁₀ O ₁₇ : Eu and Mn phosphors Eu and Mn. FIG. 1 schematically shows the concept of decay time of Eu and Mn.

The present invention is based on the fact that when the UV-LED PKG is driven at a high current, the luminance saturation due to different decay times of BaMgAl ₁₀ O ₁₇ : Eu, Mn phosphors Eu and Mn is limited, Mn ratio in order to overcome this problem.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems of the conventional art,

There is provided a phosphor composition comprising a green phosphor represented by the following formula (1), a blue phosphor represented by the following formula (2), and a red phosphor represented by the following formula (3).

[Chemical Formula 1]

Ba _{1 - x} Mg _{1 - y} Al ₁₀ O ₁₇ : Eu _x , Mn _y

Here, 0 < x < 0.5 and 0.1 < y < 0.5.

(2)

Sr _(5-xy) Ca _x (PO ₄ ) ₃ Cl: Eu _y

Where 0 < x < 1, 0 < y < 0.5

(3)

_{(Sr 1 -x Eu x) 2} Si 5 TE y N (8 + y) - z O 3/2 * z

Here, TE = Group 3 element including Al, Ga and In, x = 0.02, 0 <y = 1, 0 = z <1.

The present invention also provides a method for controlling the saturation phenomenon in driving a high-current LED by controlling the content of BaMgAl ₁₀ O ₁₇ : Eu, Eu of a phosphor of Mn, or Mn.

By controlling the amount of Eu and Mn added to the green phosphor BaMgAl ₁₀ O ₁₇ : Eu and Mn through the present invention, it is possible to improve the luminance saturation phenomenon caused by increasing the LED PKG current, It is possible to apply the green phosphor for reproduction UV-LED BLU, thus realizing the premium LED BLU.

Fig. 1 is a schematic diagram for decay time of Eu and Mn.
FIG. 2 is a graph showing the relationship between Eu content and BaMgAl ₁₀ O ₁₇ : Eu, Mn Phosphor Powder PL characteristics .
3, BaMgAl ₁₀ O ₁₇ : Eu, Mn Phosphor Powder PL characteristics .
4 is a graph showing the relationship between Eu content and BaMgAl ₁₀ O ₁₇ : Eu, Mn The spectrum of the LED PKG current including the phosphor is shown in .
5, BaMgAl ₁₀ O ₁₇ : Eu, Mn The spectrum of the LED PKG current including the phosphor is shown in .

Hereinafter, the present invention will be described in detail.

According to an aspect of the present invention,

A green phosphor represented by the following general formula (2), and a red phosphor represented by the following general formula (3).

[Chemical Formula 1]

Ba _{1 - x} Mg _{1 - y} Al ₁₀ O ₁₇ : Eu _x , Mn _y

Here, 0 < x < 0.5 and 0.1 < y < 0.5.

(2)

Sr _(5-xy) Ca _x (PO ₄ ) ₃ Cl: Eu _y

Where 0 < x < 1, 0 < y < 0.5

(3)

_{(Sr 1 -x Eu x) 2} Si 5 TE y N (8 + y) - z O 3/2 * z

Here, TE = Group 3 element including Al, Ga and In, x = 0.02, 0 <y = 1, 0 = z <1.

In particular, the green phosphor can be used as a UV-LED phosphor, and the LED backlight unit employing the same can be applied to a premium-grade TV. Since the green phosphor contains Mn and Eu together, the green phosphor exhibits different decay times, which is undesirable because a problem of afterglow may occur in a PDP that is a self-luminous display.

According to another aspect of the present invention,

BaMgAl ₁₀ O ₁₇ : The saturation phenomenon at the time of UV-LED high current driving by controlling the content of Eu or Mn of the phosphor of Eu, Mn is controlled.

Hereinafter, the present invention will be described in more detail by way of examples. It is to be understood that the following embodiments are for the purpose of illustration only and are not intended to limit the scope of the present invention.

Example

The phosphor PL spectra and the LED PKG spectra were measured while varying the Eu and Mn concentrations of the BaMgAl ₁₀ O ₁₇ : Eu, Mn phosphors.

Phosphor PL  spectrum

The PL characteristic of the phosphor was excited to 400 nm with respect to the concentration of Eu and Mn to confirm the optical characteristics .

The results are shown in FIG. 2 and FIG. 3. FIG. 2 shows that the content of Mn is fixed to 0.3 mol, the content of Eu is adjusted to 0.005 to 0.08 mol, 0.3 to 0.6 mol.

LED PKG  spectrum

For the LED PKG spectrum, current was measured by applying stepwise from 10mA to 400mA.

The results are shown in FIGS. 3 and 4, and the lower one of FIGS. 3 and 4 shows the intensity of the 515 nm wavelength for each current.

As can be seen from FIG. 3 and FIG. 4, when the content of Eu and Mn is minimized (Eu = 0.01), the saturation phenomenon is slowed down.

Claims (3)

1. A phosphor composition comprising a green phosphor represented by the following formula (1), a blue phosphor represented by the following formula (2) or a red phosphor represented by the following formula (3).
[Chemical Formula 1]
Ba _1-x Mg _1-y Al ₁₀ O ₁₇ : Eu _x , Mn _y
Here, 0 < x < 0.5 and 0.1 < y < 0.5.
(2)
Sr _(5-xy) Ca _x (PO ₄ ) ₃ Cl: Eu _y
Where 0 < x < 1, 0 < y < 0.5
(3)
(Sr _1-x Eu _x ) ₂ Si ₅ TE _y N _{(8 + y) -z} O _{3/2 * z}
Here, TE = Group 3 element including Al, Ga and In, x = 0.02, 0 <y = 1, 0 = z <1. delete The phosphor composition of claim 1, wherein the phosphor composition is for a UV-LED backlight unit.

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