KR20130059674A - Frit glass plate with sulfide phosphor and light emitting device using it - Google Patents

Abstract

PURPOSE: A frit glass plate with sulfide phosphor and a light emitting device using the same are provided to improve the chemical stability against the moisture of sulfide phosphor by using a frit glass. CONSTITUTION: A light emitting device(10) includes a reflector cup(4), a blue light emitting diode(3), and a frit glass plate(5). The blue light emitting diode is mounted on the bottom part of a reflector cup(4). The frit glass plate is separated from the blue light emitting diode. The frit glass plate includes sulfide phosphor(6) and a yellow fluorescent material(7). The sulfide phosphor(6) and the yellow fluorescent material are randomly distributed.

Description

Frit glass plate with sulfide phosphor and light emitting device using it

The present invention relates to a frit glass plate containing a sulfide phosphor, and more particularly, to a stabilization of a sulfide phosphor included in a frit glass plate and a light emitting device using the same.

In general, the phosphor material for wavelength conversion is used as a material for converting specific wavelength light of various light sources into the desired wavelength light. In particular, among the various light sources, the light emitting diode may be usefully applied as an LCD (Liquid Crystal Device) backlight, an automobile lighting device, and a home lighting device due to low power driving and excellent light efficiency. Therefore, recently, a phosphor material required for manufacturing an LED (Light Emitting Diode) has been in the spotlight.

Among the light emitting devices, a white light emitting device that generates white light by a combination of a blue light LED and a yellow phosphor, a combination of a blue light LED and a green and red phosphor, and a combination of an ultraviolet LED and a red, green and blue phosphor mixture has been widely studied. Among the above forms, it is known that a white light emitting device in which a red (R), green (G), and blue (B) phosphor mixture is combined with an ultraviolet LED has excellent white characteristics close to natural light.

The problem to be solved by the present invention is to increase the chemical stability of the sulfide phosphor against water using frit glass.

Another object of the present invention is to provide a new light emitting device using frit glass to provide a light emitting device having excellent long life and reliability.

One embodiment of the present invention relates to a light emitting device including a frit glass plate containing a sulfide phosphor. The light emitting device includes a reflector cup, a blue light emitting diode mounted in the reflector cup, and a frit glass plate spaced apart from the blue light emitting diode on the reflector cup, wherein the frit glass plate includes a phosphor different from a sulfide phosphor. It includes a light emitting device characterized in that.

According to an embodiment of the present invention, the frit glass plate containing the sulfide phosphor does not generate yellowing phenomenon occurring in the organic epoxy resin after a long time use of the light emitting device, and ensures stability of the sulfide phosphors against moisture, thereby ensuring reliability of the light emitting device. It can be secured.

According to the exemplary embodiment of the present invention, the frit glass plate including the sulfide phosphor is separated from the LED chip, and has an advantage of effectively dissipating heat generated from the LED chip.

1 is a flowchart for forming a frit glass plate forming method including a sulfide phosphor according to an embodiment of the present invention.
2 is a cross-sectional view showing a light emitting device using a frit glass plate containing a sulfide phosphor according to an embodiment of the present invention.
Figure 3 is a graph comparing the light emission characteristics of the phosphor using a CaS: Eu powder and a frit glass plate containing CaS: Eu according to an embodiment of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS The advantages and features of the present invention, and how to accomplish them, will become apparent by reference to the embodiments described in detail below with reference to the accompanying drawings. The present invention may, however, be embodied in many different forms and should not be construed as being limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of the invention to those skilled in the art. Is provided to fully convey the scope of the invention to those skilled in the art, and the invention is only defined by the scope of the claims. Like reference numerals refer to like elements throughout the specification.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. In the present specification, the singular form includes plural forms unless otherwise specified in the specification. As used herein, the terms 'comprises' and / or 'comprising' mean that the stated element, step, operation and / or element does not imply the presence of one or more other elements, steps, operations and / Or additions.

In addition, the embodiments described herein will be described with reference to cross-sectional views and / or plan views, which are ideal illustrations of the present invention. In the drawings, the thicknesses of films and regions are exaggerated for effective explanation of technical content. Thus, the shape of the illustrations may be modified by manufacturing techniques and / or tolerances. Accordingly, the embodiments of the present invention are not limited to the specific forms shown, but also include variations in forms generated by the manufacturing process. For example, the etched area shown at right angles may be rounded or may have a shape with a certain curvature. Thus, the regions illustrated in the figures have schematic attributes, and the shapes of the regions illustrated in the figures are intended to illustrate specific types of regions of the elements and are not intended to limit the scope of the invention.

1 is a flowchart for forming a frit glass plate forming method including a sulfide phosphor according to an embodiment of the present invention.

Referring to FIG. 1, frit glass, a red sulfide phosphor, and a yellow phosphor are mixed. (S10) The frit glass includes silicate-based frit glass, borosilicate frit glass, and phosphor-silicate. It may be a (phosphor-silicate) frit glass, a phosphor (Phosphor) frit glass, borate (Borate) frise glass. The silicate-based frit glass may be SiO 2 -B 2 O 3 —ZnO—P 2 O 5. The red sulfide phosphor may be CaS: Eu or (Ca, Sr) S: Eu. The yellow phosphor may be YAG: Ce or (Ca, Sr, Ba) (Al, In, Ga) 2 S 4: Eu (thiogallate phosphor).

The frit glass, the red sulfide phosphor, and the yellow phosphor are weighed in a glove box filled with argon (Ar) gas, placed in a mortar, and then ground and mixed for about 10 minutes. The reason for using the glove box filled with the argon (Ar) gas is to prevent oxidation of the sulfide red phosphor.

The mixed frit glass and the phosphor are heat-treated. (S20) The mixed frit glass and the phosphor are contained in a graphite crucible. The reason for not using a common aluminum crucible is to prevent the frit glass from reacting with the alumina crucible during the heat treatment. After the graphite crucible is put into a heating furnace, heat treatment is performed at 600 ° C. for 30 minutes in the heating furnace.

The frit glass plate containing the phosphor is manufactured and stabilized. (S30) The molten frit glass containing the phosphor formed by the heat treatment process is poured into a plate preheated to about 300 ° C., and then 300 ° in another heating furnace. Cool slowly at C for 2 hours.

2 is a cross-sectional view illustrating a light emitting device using a frit glass plate including a yellow phosphor and a sulfide phosphor according to an embodiment of the present invention.

Referring to FIG. 2, the light emitting device 10 includes a reflector cup 4 and a frit glass plate including a blue light emitting diode 3 mounted on a bottom portion of the reflector cup 4, a yellow phosphor, and a sulfide phosphor. (5) is included. The blue light emitting diode 3 is a (Al, In, Ga) N series light emitting diode and emits ultraviolet rays or blue light in the range of 420 to 490 nm. An inner surface of the reflector cup 4 may be coated with a reflective material such as aluminum (Al) or silver (Ag). The aluminum (Al) and the silver (Ag) may serve to reflect light incident from the blue light emitting diode path 3 to the reflector cup 4 to face upward. The reflector cup 4 includes a frit glass plate 5 including a yellow phosphor and a sulfide phosphor. The sulfide phosphor may be a red phosphor CaS: Eu (6). The yellow phosphor of the frit glass plate 5 may be YAG: Ce (7). The phosphors are randomly distributed.

The frit glass plate 5 including the sulfide phosphor is mounted away from the blue light emitting diode 3. Therefore, heat generated in the blue light emitting diode 3 can be easily released. In addition, when the phosphor was mixed with an organic epoxy resin, the light emission characteristics of the light emitting device were deteriorated by the reaction between the yellowing phenomenon of the epoxy resin and the moisture of the sulfide phosphor. The reliability of the light emitting device can be improved by replacing the frit glass plate.

3 is a graph comparing light emission characteristics of CaS: Eu powder and frit glass plate including CaS: Eu according to an embodiment of the present invention, and is a graph of wavelength (nm) -intensity (a.u.).

Referring to FIG. 3, the frit glass plate includes 10 g of SiO 2 -B 2 O 3 —ZnO-P 2 O 5 frit glass and 3 g of CaS: Eu, and compared with 3 g of CaS: Eu powder in the same amount. As a result of using an excitation wavelength of 450 nm, which is a blue wavelength, the red light emission characteristic of the frit glass plate containing CaS: Eu at about 650 nm wavelength was about 90% of the red light emission characteristic of the same amount of Cas: Eu powder. Effect.

3: blue light emitting diode
4: reflector cup
5: fritted glass plate
6: CaS: Eu
7: YAG; Ce
10: Light emitting element

Claims (1)

Reflector cups;
A blue light emitting diode mounted on a bottom portion of the reflector cup; And
A frit glass plate spaced apart from the blue light emitting diode on the reflector cup,
The frit glass plate includes a sulfide phosphor and another phosphor.

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