Source: https://patents.justia.com/patent/7501656
Timestamp: 2019-07-20 01:07:53
Document Index: 733757307

Matched Legal Cases: ['Application No. 2005', 'art 220', 'art 220', 'art 220', 'art 220', 'art 220']

US Patent for Light emitting diode package with diffuser and method of manufacturing the same Patent (Patent # 7,501,656 issued March 10, 2009) - Justia Patents Search
Justia Patents Incoherent Light Emitter StructureUS Patent for Light emitting diode package with diffuser and method of manufacturing the same Patent (Patent # 7,501,656)
Jul 25, 2006 - Samsung Electronics
This application claims the benefit of Korean Patent Application No. 2005-67859 filed on Jul. 26, 2005, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference.
The conventional LED package 200, disclosed in U.S. Patent No. 2005-0057144, includes a substrate 205 with electrode patterns 207a and 207b formed thereon, and an LED chip 210 mounted on the electrode pattern 207b and electrically connected to the electrode patterns 207a and 207b by wires 211.
In addition, a wavelength-converting material part 220 is formed in an inner space of the reflecting frame 212 where the LED chip 210 is mounted. The wavelength-converting material part 220 comprises transparent resin containing a phosphor 222a and a diffuser 222b, and encapsulates the LED chip 210.
In the above-described LED package 200, when emission takes place from the LED chip 210 and light is emitted, the light is directed to the wavelength-converting material part 220 by the reflecting layer 214. The light then collides with the phosphor 222a contained in the wavelength-converting part 220 to excite the phosphor 222a, and is scattered by a plurality of diffusers 222b contained in the wavelength-converting material part 220. As a result, light having a longer wavelength than the light that was incident onto the phosphor 222a exits the package due to the interaction between the phosphor 222a and the diffuser 222b.
Although the conventional technology is useful for elongating the wavelength of light emitted from the LED chip 210 and emitting white light, it does not necessarily allow uniform light emission. The conventional technology allows color mixing to generate white light, but emits white light only forward without a variety in radiating angles. Further, as it realizes white light using the phosphor 222a, it has mediocre color reproducibility.
As disclosed in Japanese Patent Application Publication No. 2001-60724, the LED package 250 includes an LED chip 260 positioned in a lamp housing 255 having a hollow part, electrodes 262a and 262b drawn out from the LED chip 260, and an encapsulant 270 filled in the lamp housing 255 for fixing the LED chip 260 and the electrodes 262a and 262b.
In such a conventional LED package 250, the glass beads 272 in the encapsulant 270 of transparent thermosetting resin function as a diffuser and scatter light to some degree. However, the light is directed only forward in a not-so-wide radiating angle due to the hollow part of the lamp housing 255, and it is difficult to reduce the thickness of the LED package 250 due to the structural characteristics of the electrodes 262a and 262b and the lamp housing 255.
FIG. 3 illustrates yet another conventional LED package 300. The conventional LED package 300 includes a base substrate 305 with electrodes 310a and 310b formed thereon, an LED chip 312 mounted on and connected to the electrodes 310a and 310b, and a molded frame 315 having a groove, thus being fixed around the LED chip 312.
Then, a molding member 317 containing a diffuser 317a is filled in the groove of the molded frame 315. This conventional LED package 300 achieves high luminance and contrast ratio using the diffuser 317a contained in the molding member 317 made of transparent resin, thereby enabling a high contrast display in a large angle of visibility in high precision.
FIGS. 9(a) and (b) are views illustrating the LED packages using a diffuser of the invention disposed in an array to be used for an LCD backlight.
As shown in FIG. 4, an LED package 1 using a diffuser according to the present invention has a substrate 10 with electrodes 5a and 5b formed thereon. The substrate 10 preferably has a planar structure molded with molding material, and has each of the electrodes 5a and 5b formed thereon to provide power to an LED chip 20 described later.
The LED chip 20 is mounted on an upper part of the substrate 10 and electrically connected to the electrodes 5a and 5b by wire bonding, etc. The invention is applicable to either a horizontal type of LED chip 20 with all electric terminals formed on an upper surface thereof, or a vertical type of LED chip 20 with electric terminals formed on both upper and lower surfaces thereof.
In addition, a step 25 is formed on an upper surface of the substrate 10 to surround the portion where the LED-chip 20 is mounted.
The manufacturing method of the LED package using a diffuser starts with a step of providing the substrate 10 with the electrodes 5a and 5b formed thereon.
The electrodes 5a and 5b are formed on the substrate 10 to supply power to the LED chip 20, and as described later, the step 25 is formed on an upper surface of the substrate 10, surrounding the portion where the LED chip 20 is mounted.
Next, the LED chip 20 is disposed on the substrate 10. The LED chip 20 is mounted on the substrate 10, and electrically connected to the electrodes 5a and 5b of the substrate 10 by wire bonding.
a substrate with an electrode formed thereon;
a light emitting diode chip mounted on the substrate;
an encapsulant applied around the light emitting diode chip, the encapsulant containing a diffuser; and
a lens part disposed on the light emitting diode chip and the encapsulant to radiate light in a wide angle,
2. The light emitting diode package according to claim 1, wherein the substrate has a step formed on an upper surface thereof, the step surrounding a portion of the substrate where the light emitting diode chip is mounted.
3. The light emitting diode package according to claim 1, wherein the substrate has a reflective layer formed on a side surface of a recessed portion formed on an upper surface thereof, the reflective layer surrounding the light emitting diode chip mounted on the substrate.
4. The light emitting diode package according to claim 1, wherein the lens part is made of a material mixed with a phosphor.
5. The light emitting diode package according to claim 1, wherein the lens part is made of a material mixed with a diffuser.
6. The light emitting diode package according to claim 1, wherein the lens part is made of a material mixed with a phosphor and a diffuser.
20020011601 January 31, 2002 Furukawa et al.
20050057144 March 17, 2005 Morita et al.
20050253159 November 17, 2005 Creswick et al.
1336693 February 2002 CN
1492506 April 2004 CN
5-240665 September 1993 JP
2001-060724 March 2001 JP
2002-176201 June 2002 JP
Patent number: 7501656
Patent Publication Number: 20070045644
Inventors: Seong Yeon Han (Suwon), Seon Goo Lee (Gunpo), Chang Ho Song (Seoul), Jung Kyu Park (Seoul), Young Sam Park (Seoul), Kyung Taeg Han (Hwasung)
Application Number: 11/491,947
Current U.S. Class: Incoherent Light Emitter Structure (257/79); With Reflector, Opaque Mask, Or Optical Element (e.g., Lens, Optical Fiber, Index Of Refraction Matching Layer, Luminescent Material Layer, Filter) Integral With Device Or Device Enclosure Or Package (257/98); Light Emitting Semiconductor Devices Having A Potential Or A Surface Barrier, Processes Or Apparatus Peculiar To The Manufacture Or Treatment Of Such Devices, Or Of Parts Thereof (257/E33.001)
International Classification: H01L 27/15 (20060101); H01L 31/12 (20060101); H01L 33/00 (20060101);