LED device and portable telephone, digital camera and LCD apparatus using the same

• US 7,176,612 B2
• Filed: 04/21/2004
• Issued: 02/13/2007
• Est. Priority Date: 04/21/2003
• Status: Active Grant

• Current Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Original Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Inventors: Masuda, Masatsugu, Omoto, Masatoshi, Kitano, Masaharu
• Primary Examiner(s): Patel; Nimeshkumar D.
• Assistant Examiner(s): MACCHIAROLO, PETER J
• Application Number:
  US10/830,379
• Publication Number:
  US 20040207313A1
• Time in Patent Office: 1,028 Days
• Field of Search: 313/487, 313/468, 257/80, 257/84
• US Class Current: 313/487
• CPC Class Codes: C09K 11/0883 Arsenides; Nitrides; Phosphides
• CPC Class Codes: C09K 11/54 containing zinc or cadmium
• CPC Class Codes: C09K 11/584 with zinc or cadmium
• CPC Class Codes: C09K 11/595 with zinc or cadmium
• CPC Class Codes: C09K 11/62 containing gallium, indium or thallium
• CPC Class Codes: C09K 11/662 with zinc or cadmium
• CPC Class Codes: C09K 11/7729 Chalcogenides
• CPC Class Codes: C09K 11/7734 Aluminates
• CPC Class Codes: H01L 2224/45144 Gold (Au) as principal constituent
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48247 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2224/48465 the other connecting portion not on the bonding area being a wedge bond, i.e. ball-to-wedge, regular stitch
• CPC Class Codes: H01L 25/0753 the devices being arranged next to each other
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/00012 Relevant to the scope of the group, the symbol of which is combined with the symbol of this group
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 2924/181 Encapsulation
• CPC Class Codes: H01L 33/502 Wavelength conversion materials
• CPC Class Codes: H01L 33/504 Elements with two or more wavelength conversion materials
• CPC Class Codes: H04N 23/56 provided with illuminating means
• CPC Class Codes: Y02B 20/00 : Energy efficient lighting technologies, e.g. halogen lamps or gas discharge lamps

Abstract

An LED device at least including a blue light emitting element having peak emission wavelength of 420 nm to 480 nm, a green fluorescent substance having peak wavelength of fluorescent spectrum in the range of 500 nm to 580 nm with the emission of the blue light emitting element, and a red light emitting element having peak emission wavelength of 600 nm to 670 nm is provided. The device may further include an ultraviolet/violet light emitting element for exciting green fluorescent substance. As a result, an LED device capable of attaining bright white light with good color reproduction characteristic is provided.

Claims

1. An LED device, at least comprising:

a blue light emitting element having peak emission wavelength of 420 nm to 480 nm, a green fluorescent substance having peak wavelength of fluorescent spectrum in the range of 500 nm to 580 nm with the emission of said blue light emitting element, and a red light emitting element having peak emission wavelength of 600 nm to 670 nm, wherein

said green fluorescent substance having peak wavelength of fluorescent spectrum in the range of 500 nm to 580 nm is formed of at least two fluorescent substances, and wherein the fluorescent substances are selected from the group consisting of SrGa₂S₄;

Eu;

RMg₂Al₁₆O₂₇;

Eu, Mn (R is at least one element selected from Sr and Ba);

RMgAl₁₀O₁₇;

Eu, Mn (R is at least one element selected from Sr and Ba);

ZnS;

Cu;

SrAl₂O₄;

Eu;

SrAl₂O₄;

Eu, Dy;

ZnO;

Zn;

Zn₂Ge₂O₄;

Mn;

Zn₂SiO₄;

Mn; and

Q₃MgSi₂O₈;

Eu, Mn (Q is at least one element selected from Sr, Ba and Ca).

2. The LED device according to claim 1, wherein

the fluorescent substance has light transmitting characteristic and refractive index n of n>

1, and said fluorescent substance is coated with a heat-resistant, water-proof and light transmitting coating.

3. The LED device according to claim 1, wherein

grain size of the fluorescent substance is at most 20 μ

m.

4. A digital camera using, as an auxiliary light source of a CCD or CMOS camera, an LED device at least including:

a blue light emitting element having peak emission wavelength of 420 nm to 480 nm, a green fluorescent substance having peak wavelength of fluorescent spectrum in the range of 500 nm to 580 nm with the emission of said blue light emitting element, and a red light emitting element having peak emission wavelength of 600 nm to 670 nm, wherein said green fluorescent substance having peak wavelength of fluorescent spectrum in the range of 500 nm to 580 nm is formed of at least two fluorescent substances.

5. A portable telephone using, as an auxiliary light source of a CCD or CMOS camera, an LED device at least including:

a blue light emitting element having peak emission wavelength of 420 nm to 480 nm, a green fluorescent substance having peak wavelength of fluorescent spectrum in the range of 500 nm to 580 nm with the emission of said blue light emitting element, and a red light emitting element having peak emission wavelength of 600 nm to 670 nm, wherein said green fluorescent substance having peak wavelength of fluorescent spectrum in the range of 500 nm to 580 nm is formed of at least two fluorescent substance.

6. An LCD apparatus using, as a backlight source, an LED device at least including:

a blue light emitting element having peak emission wavelength of 420 nm to 480 nm, a green fluorescent substance having peak wavelength of fluorescent spectrum in the range of 500 nm to 580 nm with the emission of said blue light emitting element, and a red light emitting element having peak emission wavelength of 600 nm to 670 nm, wherein said green fluorescent substance having peak wavelength of fluorescent spectrum in the range of 500 nm to 580 nm is formed of at least two fluorescent substances.