JP2007080880A - Light emitting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a light emitting device which can mix colors. <P>SOLUTION: The light emitting device is provided with a plurality of LED chips 1 and 1, a package 10 as a base member wherein the LED chips 1 and 1 are mounted, and a color conversion member 20 which is arranged on the mounting face of the LED chips 1 and 1 in the package 10. A mixed color light (white light) of a blue light emitted from the LED chip 1 and a light emitted from a yellow phosphor is emitted from a first color conversion area M1 of the color conversion member 20. In addition, a mixed color light (slightly reddish white (bulb color) light) of a blue light emitted from the LED chip 1, a red light emitted from a red phosphor, and a green light emitted from a green phosphor, is emitted from a second color conversion M2 of the color conversion member 20. Therefore, a blue light is alternatively emitted from either of the two LED chips 1 and 1, or blue lights are emitted from both LED chips 1 and 1, thereby permitting mixing of colors. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a light emitting device using an LED chip (light emitting diode chip).

Conventionally, an LED chip, a base member on which the LED chip is mounted, and a light of a color different from the emission color of the LED chip when excited by light emitted from the LED chip disposed on the LED chip mounting surface side of the base member. There has been proposed a light-emitting device including a color conversion member made of a molded product obtained by molding a radiating fluorescent material together with a transparent material (see, for example, Patent Document 1). As this type of light-emitting device, for example, a white light-emitting device (generally white light-emitting device) that obtains white light (white light emission spectrum) by mixing an LED chip that emits blue light and a phosphor that emits yellow light. It is called LED.) Has been commercialized.
JP 2001-148514 A

  However, in the above-described conventional device, one type of light emission color (for example, white) is obtained by mixing a plurality of types of light having different emission colors, and light of a plurality of types of colors is switched and emitted (hereinafter, referred to as “color”). Called "Toning").

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a light-emitting device capable of toning.

  In order to achieve the above object, the invention according to claim 1 is a plurality of LED chips, a base member on which each LED chip is mounted, and a LED chip disposed on the mounting surface side of each LED chip in the base member. And a color conversion member made of a molded product obtained by molding together with a transparent material a fluorescent material that emits light of a color different from the light emission color of the LED chip. The color conversion member emits light of different colors. A plurality of types of fluorescent materials are individually distributed in a plurality of color conversion regions, and the plurality of color conversion regions are arranged so as to substantially correspond to the light emission range of each LED chip. Features.

  The invention of claim 2 is characterized in that, in the invention of claim 1, a condensing lens member is provided between each LED chip and the color conversion member.

  According to a third aspect of the present invention, in the first or second aspect of the present invention, a light-shielding wall that shields light emitted from an LED chip that has a one-to-one correspondence with another adjacent color conversion region is provided for each LED chip and the color conversion region. It is provided between.

  According to the first aspect of the present invention, it is possible to perform color matching by switching and emitting light of a plurality of types of colors by selectively emitting light from a plurality of LED chips.

  According to the second aspect of the present invention, since light is efficiently radiated to each color conversion region, the light leaking to the adjacent color conversion region is reduced, and the occurrence of color unevenness can be suppressed.

  According to invention of Claim 3, the light which leaks to the color conversion area | region adjacent by a light-shielding wall reduces, and generation | occurrence | production of color unevenness can be suppressed.

  As shown in FIGS. 1A and 1B, the light emitting device of this embodiment includes a plurality (two in the illustrated example) of LED chips 1 and 1 and a package as a base member on which the LED chips 1 and 1 are mounted. 10 and a color conversion member 20 disposed on the mounting surface side of the LED chips 1 and 1 in the package 10.

  The package 10 is formed in a substantially rectangular parallelepiped shape with a ceramic material, and a conical recess 11 is provided on one surface, and two LED chips 1 and 1 are mounted on the bottom surface of the recess 11. A light shielding wall 12 that rises from the bottom surface of the recess 11 toward the opening surface is provided between the two LED chips 1 and 1. A reflective surface made of a highly reflective material (for example, alumina) is formed on the inner peripheral surface of the recess 11 facing the LED chips 1 and 1 and the side surface of the light shielding wall 12. The light emitted from 1 is efficiently emitted from the opening surface of the recess 11.

  The LED chips 1 and 1 are GaN-based blue LED chips that emit blue light, and are formed of a GaN-based compound semiconductor material on the main surface side of a crystal growth substrate made of a sapphire substrate, and have, for example, a double heterostructure. A light emitting portion made of a laminated structure is grown by an epitaxial growth method (for example, MOVPE method). The LED chips 1 and 1 are mounted on the package 10 by bonding an anode electrode and a cathode electrode (not shown) to gold bumps (not shown) formed on the bottom surface of the recess 11. Moreover, in order to condense the light which LED chip 1,1 radiates | emits, the lens members 2 and 2 which comprise a plano-convex lens are arrange | positioned at the surface (upper surface in FIG.1 (b)) of LED chip 1,1. .

  The color conversion member 20 is composed of a molded product obtained by molding a transparent material such as a silicone resin into a rectangular flat plate shape, and one of the two regions separated by a center line (broken line in FIG. 1A). (Hereinafter, it is referred to as a first color conversion region.) In M1, a fluorescent material composed of a particulate yellow phosphor that is excited by blue light emitted from the LED chips 1 and 1 and emits broad yellow light. In the other region (hereinafter referred to as the second color conversion region) M2, a particulate red phosphor that emits red light when excited by the blue light emitted from the LED chips 1 and 1 is used. And a fluorescent material made of a green phosphor that emits green light are mixed. The color conversion member 20 configured as described above is coupled to the package 10 so that the center line thereof overlaps the light shielding wall 12 when viewed from the front (upper side in FIG. 1) and closes the opening of the recess 11. Yes. Therefore, the mixed color light (white light) of the blue light emitted from the LED chip 1 and the light emitted from the yellow phosphor is emitted from the first color conversion region M1 of the color conversion member 20 and emitted from the LED chip 1. The mixed light of the blue light emitted from the red phosphor and the green light emitted from the red phosphor and the green light emitted from the green phosphor (light with a slightly reddish white color (so-called light bulb color)) is the second light of the color conversion member 20. The light is emitted from the color conversion area M2.

  Thus, in the light emitting device according to the present embodiment, the blue light is emitted only from the LED chip 1 corresponding to the first color conversion region M1, and white light is emitted from the first color conversion region M1 to the outside. Then, by emitting blue light only from the LED chip 1 corresponding to the second color conversion region M2, light bulb color light is emitted from the second color conversion region M2 to the outside, and two LED chips 1 are further emitted. , 1 can radiate blue light from the first and second color conversion regions M1 and M2 to the outside and emit light of a plurality of types of colors. It is possible to perform so-called toning in which the light is switched. In this embodiment, since the light shielding wall 12 is provided between the two LED chips 1 and 1 and the color conversion regions M1 and M2, light leaking to the adjacent color conversion regions M1 and M2 is reduced by the light shielding wall 12. Occurrence of uneven color can be suppressed.

  Incidentally, in the present embodiment, the first and second color conversion regions M1 and M2 are formed in a target rectangular shape with the center line in between, but as shown in FIG. The color conversion member 20 is divided into four regions along the center line (broken line in the figure), the two regions adjacent on the diagonal are defined as the first color conversion region M1, and the remaining two regions adjacent on the diagonal are defined as the first region. Two color conversion regions M2 may be provided, and a total of four LED chips 1 may be mounted on the bottom surface of the recess 11 facing each region. Alternatively, as shown in FIG. 1D, fluorescent materials made of phosphors that emit different emission colors are mixed in the four divided regions, and light of four different colors is emitted to the outside. Color conversion regions M1, M2, M3, and M4 may be formed.

(A) is a perspective view showing an embodiment of the present invention, (b) is a cross-sectional view, (c) is a plan view of a color conversion member of another configuration, and (d) is a plane of a color conversion member of still another configuration. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 LED chip 10 Package 11 Recess 12 Light shielding wall 20 Color conversion member M1 1st color conversion area M2 2nd color conversion area

Claims (3)

  A plurality of LED chips, a base member on which each LED chip is mounted, and a color different from the emission color of the LED chip excited by light emitted from the LED chip disposed on the mounting surface side of each LED chip in the base member A color conversion member made of a molded product obtained by molding a fluorescent material that emits light together with a transparent material, and the color conversion member individually includes a plurality of types of fluorescent materials that emit light of different colors in a plurality of color conversion regions. A light emitting device characterized in that the plurality of color conversion regions are arranged so as to substantially correspond to the light emission range of each LED chip.   The light-emitting device according to claim 1, wherein a condensing lens member is provided between each LED chip and the color conversion member.   3. A light-shielding wall that shields light emitted from LED chips that are in one-to-one correspondence with other adjacent color conversion regions is provided between each LED chip and the color conversion region. Light-emitting device.

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