TW200417051A - Light-emitting device to emit white light - Google Patents

Abstract

A light-emitting device to emit white light comprises: an optical semiconductor for use as the light source of blue light; and a fluorescent layer bonded on the optical semiconductor by adhesive, which is characterized in that: the fluorescent layer is formed by mixing uniformly the fluorescent powder with red and green colors and transparent adhesive. The red fluorescent element in the fluorescent layer is excited by blue light and emits light with wavelengths different from that of the blue light. The green fluorescent element in the fluorescent layer is excited by blue light and emits light with wavelengths different from that of the blue light. The two different spectra (wavelengths) are mixed with part of the unexcited blue light spectrum and form white light.

Description

200417051 V. Description of the invention (1) Technical field to which the invention belongs: The present invention provides a white light emitting device, particularly a device having a pure white light emitting diode (L E D). Prior technology: According to the conventional white LED, a typical example, such as Taiwan Patent Publication No. 3 8503, "New White LED" invention case, which uses ultraviolet semiconductor as a light source to excite red, green, The coating layer of blue (R, G, B) three-color phosphor powder and transparent glue is mixed to make white light appear. However, the light source of this light-emitting device is ultraviolet light, which will cause damage to the epoxy resin structure currently used, causing the final "white light" to cause the problem of light attenuation, and the brightness of white light is not strong, especially in this case. The coating layer is made by mixing three colors of red, green, and blue phosphors. The ratio and process of the three pigments are difficult to control and are one of its disadvantages. Taiwan Patent Bulletin No. 3 8 3 5 0 8 "Light-emitting device and display device" patent case, the photoluminescence fluorescence system includes Y, La, Gd and Sm-at least one element selected from the group and At least one element selected from the group A1, Ga, and I η — and a living garnet phosphor that has been activated by tritium. However, the pomegranate-based phosphor that is activated by radon is essentially a yellow phosphor. Among them, a thallium nitride semiconductor light-emitting element that emits short-wavelength blue light is used as a light source. The light source emits blue light to excite yellow fluorescent light. The layer generates white light with different wavelengths. Since only a single wavelength of light is mixed with some unexcited blue light, its color rendering is poor, that is, the white light is not pure.

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V. Description of the invention (3) The luminescence spectrum (wavelength) of the rural fluorescent color system is 6 20 nm after being triggered by the blue light source, and the luminescence spectrum (wavelength) of the green fluorescence system after being triggered by the blue light source is 5 20nm The blue light emission spectrum is between 43 0 and 48 0 nm. According to the foregoing main features, the red phosphor can be replaced by an orange-red glory powder. The orange-red phosphor can be a YAG · · C e series (that is, & decorated as an activated pomegranate series), which is affected by blue light. The light emission spectrum after the light source is triggered is 590 nm. According to the aforementioned main features, the fluorescent layer 20 can encapsulate and encapsulate the optical semiconductor 10 into a granular structure (as shown in FIG. 1). According to the foregoing main features, the optical semiconductor 10 and the fluorescent layer 20 can fill and cover the upper gap 6 2 of the reflective cover 60, and the inner wall surface of the upper gap 6 2 forms a light reflecting surface (see FIG. 3). , As shown in Figure 4). The present invention further provides a white light emitting device (as shown in FIG. 2A), which includes: an optical semiconductor 10 as a blue light source, which is characterized by:-a cap 5 5 with a groove 5 2 inside, the cap The sleeve 50 is formed by a transparent plastic 80 body. The groove wall surface 5 2 1 is evenly coated or plated with a fluorescent layer 2 〇 'The glory layer 2 〇 can be red (or orange-red) and green fluorescent powder & amp Transparent plastic 80 is evenly mixed; towel sleeve 50 can be put on the optical semiconductor 10. According to the above-mentioned minor temples, it can be directly formed from red or mixed to make the white light emitting device described in the cap 5, wherein the 5 5 color of the cap and the green fluorescent powder and transparent plastic 8 0 uniform 0 directly to form fluorescent Layer 2 0 (as shown in Figure 2B)

200417051 V. Description of Invention (4)). Embodiments: (1). As shown in Figure 1, the device is centered on the optical semiconductor 10, and the bottom is a conductive body connected to the left lead frame 30 with a conductive adhesive 12, and the fluorescent layer 20 is coated. Packaged on the optical semiconductor 10, the lead S is shuttled from above the optical semiconductor 10 and connected to the right lead frame 32 to form an electrical circuit, in which the transparent adhesive 80 connects the optical semiconductor 10, the fluorescent layer 20 and the left The upper half of the right and left lead frames 30 and 32 are covered to form a granular structure. The optical semiconductor 10 is preferably made of a nitride-based compound semiconductor, which can emit blue light as a light source; the fluorescent layer 20 is composed of red and green fluorescent powder and transparent glue in an appropriate ratio. For example, when the optical semiconductor 10 emits blue light, the main peak wavelength of the blue light is in the range of 4 30 to 480 nm, and the red phosphor powder in the fluorescent layer 20 is YAG: EU system (that is, activated by thallium element). Pomegranate series). When the red fluorescent layer is excited by blue light, the wavelength of blue light is changed, and the main peak of the spectral wavelength is emitted at 6 2 0 nm. The green phosphor powder is S r G a 2 S 4 : The EU system (that is, the weighted system activated with plutonium) is excited by blue light to change the wavelength of blue light, and emits with the main peak of the spectral wavelength being 5 20 nm. Therefore, the red and green fluorescent layers absorb a part of the wavelength of blue light and change the wavelength of 470 nm of blue light, and further emit two kinds of light (that is, 6 2 0 η m, 520nm) that are different from the wavelength of blue light. Light of different wavelengths plus some unexcited blue light, these three different wavelengths

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When light is collected and mixed, it is defined as white light when viewed by the human eye. Because the generation of the white light is not mixed with the ultraviolet light source, the pure white light obtained has a strong intensity and is not subject to color attenuation, and especially it is a mixture of three-color light (R, G, B) to produce white light, making Good color rendering. (2). As shown in the second figure A, it shows that the cap sleeve 50 has a circular groove 5 2 in the system, and the groove wall 5 2 1 is uniformly coated or mineralized with a fluorescent layer 20. The cap 50 is sleeved on the left and right wires ^ 30 and 32 of the optical semiconductor, so that when the optical semiconductor emits blue light, the red and green fluorescent lights in the fluorescent layer 20 can be excited. Material to emit two kinds of light with different wavelengths' and transmitted through the transparent cap 5. The space in the circular groove 5 2 can be vacuum-shaped. The optical semiconductor 10 has the positive and negative conductive pins S 1 and s. 2 Welded to the left and right lead frames 30 and 32 respectively, and the left and right lead frames 30 and 32 are separated by insulation elements 35 to form an electrical circuit. The cap 50 shown in the second figure b is made of a fluorescent layer 20-a body compression molding, so the cap 50 is the fluorescent layer 20 and can also emit two kinds of light with different wavelengths. … As shown in the third picture, a reflective cover 60 is used as a base, and a fluorescent layer 20 is filled and embedded in the upper notch 62, and an optical semiconductor i. Bottom two insulating adhesives 14 are fixed to the upper notch 62. At the bottom, leads s 3 and S 4 are connected to the right lead frame 3 0 and 3 2 respectively to form an electrical circuit: the blue light emitted by the optical semiconductor 10 and the red emitted by the blue light and the fluorescent layer 20 Both green and green light can be reflected from the inner wall ^ of the upper notch 62 to the outside of the upper notch 62, so that the fluorescent layer 20 appears white.

200417051 V. Description of invention (6) Lightman. As shown in the fourth figure, the reflection cover 60 is combined with the fluorescent layer 20 and the optical semiconductor 10, and its effect is the same as the technology in the third figure. However, the leads S 3 and S 4 of the optical semiconductor 10 are shuttled from the bottom respectively. And further connected to the left and right lead frames 30 and 32 respectively to form an electrical circuit.

Page 10 200417051 Brief description of the drawings The first figure is a longitudinal sectional view of the present invention. FIG. 2A is a longitudinal sectional view of another embodiment of the present invention. FIG. 2B is a longitudinal sectional view of still another embodiment of the present invention. The third figure is a longitudinal sectional view of the present invention adhering to a reflective cover. The fourth figure is a cross-sectional view of still another embodiment of the invention adhering to a reflective cover. Part Number: Optical Semiconductor --- 10 Insulating Adhesive ---- 14 Conductive Adhesive ---- 12 Fluorescent Layer ---- 20 Left Lead Frame --- 30 Right Lead Frame --- 32 Insulation Element- -35 Cap sleeve ----- 5 0 groove ------ 5 2 groove wall ---- 5 2 1 reflection cover ---- 6 0 upper notch ---- 6 2 transparent glue- --- 8 0 pin ----- SI, S2 lead ----- S, S3, S4

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Claims (1)

200417051 6. Scope of patent application 1. A white light emitting device includes: an optical semiconductor as a blue light source; a fluorescent layer is glued on the optical semiconductor; its characteristics are: The light-emitting layer is made up of red and green fluorescent powders and transparent glue. The red fluorescent system in the fluorescent layer is excited by blue light and emits light with a different spectrum (wavelength) from blue light. Green Fluorescence is excited by blue light and emits light with a different spectrum (wavelength) than blue light. The two different spectra (wavelengths) plus some unexcited blue light spectrum are mixed to form white light. 2 · According to the white light emitting device described in item 1 of the scope of the patent application, the red phosphor is YAG: EU (ie pomegranate based on thallium) and the green phosphor is S r G a 2 S 4: EU series (namely pomegranate series activated by thallium element), in which the red fluorescence system is triggered by the blue light source (wavelength) is 6 20 nm, and the green fluorescence system is triggered by the blue light source The emission spectrum (wavelength) is 5 2 0 nm, and the emission spectrum of blue light is between 43 0 ~ 480 η in. 3. According to the white light emitting device described in item 1 of the scope of the patent application, the red fluorescent powder can be replaced by orange-red fluorescent powder, and the orange-red fluorescent powder can be YAG: C e series (Live pomegranate series) 'The luminescence spectrum after being triggered by a blue light source is 590 nm. 4 The white light emitting device according to item 1 of the scope of patent application, wherein the fluorescent layer can encapsulate and encapsulate the optical semiconductor into a granular structure. Page 12 200417051 5 Scope of patent application -------~ ----% L ^ According to the white light emitting device described in item 1 of the scope of patent application, the conductor and the fluorescent layer can be filled and covered on the reflective cover In the notch, the inner wall surface of the j notch forms a light reflecting surface. I white light emitting device includes: ~ optical semiconductor as a blue light source, which is characterized by: ~ a cap with a groove inside, which is integrally formed by transparent glue, and the groove wall is evenly coated or mineralized An upper layer of light, which can be made by mixing red or orange red with green fluorescent powder and transparent glue uniformly; the cap can be placed on the optical semiconductor. According to the white light-emitting device described in item 6 of the scope of the patent application, the cap sleeve can be directly formed by uniformly mixing red or orange-red and green fluorescent powder with transparent powder, so that the cap sleeve directly forms a light-emitting layer. Page 13