Reflection type red fluorescent ceramic packaging structure for laser display

Abstract

The invention discloses a reflective red fluorescent ceramic packaging structure for laser display, and relates to the technical field of semiconductor illumination. The packaging structure comprises a transparent dielectric layer, an optical cement connecting layer, a red ceramic layer, a welding layer and a reflecting substrate, wherein the welding layer, the red ceramic layer, the optical cement connecting layer and the transparent dielectric layer are sequentially arranged in the reflection substrate, the red ceramic layer is connected with the reflection substrate through the welding layer, and the transparent dielectric layer is combined with the red ceramic layer through the optical cement connecting layer. The sapphire material and the optical cement connecting material are introduced to the upper surface of the light-emitting material, so that the heat dissipation performance is better, and higher power density can be realized; meanwhile, the red ceramic and the reflection substrate are connected through the welding layer, connection strength is high, stability is good, service performance is excellent, and the method is suitable for industrial application.

Description

Technical Field

[0001] The invention relates to the technical field of semiconductor lighting, and in particular to a reflective red fluorescent ceramic packaging structure for laser display. Background Art

[0002] Laser lighting and display technology can be widely used in many important fields such as car headlights, outdoor lighting, laser TVs, and laser cinemas. As the key light conversion material for laser lighting, the performance of fluorescent materials directly determines important technical parameters of lighting devices such as color rendering index, lumen efficiency, and reliability. At present, the commonly used fluorescent materials for laser lighting are fluorescent ceramics. In order to achieve high-quality white light laser lighting and improve the color rendering index of the light source, red ceramics in fluorescent ceramics are currently a hot research topic.

[0003] In the field of laser display applications, in addition to the color wheel structure, the static packaging form of red fluorescent ceramics is reflective, which is significantly different from the packaging of traditional red fluorescent powders (traditional fluorescent powder packaging forms, such as coating fluorescent silica gel on the surface of yellow fluorescent ceramics or sintering a glass layer containing red fluorescent powder). Generally, red fluorescent ceramics are directly bonded to the transparent sapphire heat dissipation substrate, but there is a certain gap between the red fluorescent ceramic layer and the sapphire substrate, which cannot effectively adhere and conduct heat. Although a bonding solution can be used to solve the above problems, the bonding solution between the two is costly and technically difficult.

[0004] In addition, since the upper surface of the red fluorescent ceramic is "hollowed out", the heat generated by the fluorescence conversion process can only be dissipated from the bottom. Different from yellow and green fluorescent ceramic materials, red fluorescent ceramics generate more heat due to the wide Stokes shift, and dissipating heat only from the bottom cannot solve the thermal focusing effect.

[0005] Therefore, based on comprehensive research progress, it is necessary to propose a reflective red fluorescent ceramic packaging structure to achieve coordinated processing of light and heat. Summary of the invention

[0006] In response to the above problems, the present invention discloses a reflective red fluorescent ceramic packaging structure for laser display, in which sapphire material and optical adhesive connecting material are introduced on the upper surface of the luminescent material, which has better heat dissipation performance and can achieve higher power density. At the same time, a welding layer is used to connect the red ceramic and the reflective substrate, which has high connection strength, good stability, excellent service performance, and is suitable for industrial applications.

[0007] According to the purpose of the present invention, a reflective red fluorescent ceramic packaging structure for laser display is proposed, including a transparent dielectric layer, an optical adhesive connecting layer, a red ceramic layer, a welding layer and a reflective substrate; wherein the welding layer, the red ceramic layer, the optical adhesive connecting layer and the transparent dielectric layer are sequentially placed inside the reflective substrate, the red ceramic layer is connected to the reflective substrate via the welding layer, and the transparent dielectric layer is combined with the red ceramic layer via the optical adhesive connecting layer.

[0008] Preferably, the transparent medium layer is one of aluminum oxide ceramics and aluminum oxide single crystals, with a refractive index of 1.76 to 1.77 at 800 nm and a transmittance of 80 to 85%.

[0009] Preferably, the refractive index of the optical adhesive connection layer at 800 nm is 1.77-1.80, and the transmittance is 95-98%.

[0010] Preferably, the shear strength of the optical adhesive connection layer is 3 to 6 MPa.

[0011] Preferably, the red ceramic layer is one of oxide and nitride systems; and the refractive index at 800 nm is 1.78-1.83.

[0012] Preferably, the red ceramic layer has an emission peak wavelength of 625-655 nm.

[0013] Preferably, the welding layer is one of solder and silver paste, and has a shear strength of 35 to 75 MPa.

[0014] Preferably, the reflective substrate is an aluminum plate, and the reflectivity at 800 nm is 85-90%.

[0015] Preferably, the fluorescence conversion efficiency of the reflective red fluorescent ceramic packaging structure is 245-255 lm / W, and the blue light saturation power density is 15-25 W / mm 2 .

[0016] Compared with the prior art, the reflective red fluorescent ceramic packaging structure for laser display disclosed in the present invention has the following advantages:

[0017] 1. The present invention innovatively introduces sapphire material and optical adhesive connection material on the upper surface of the light-emitting material, which has better heat dissipation performance and can achieve higher power density.

[0018] 2. The present invention designs an intermediate transition layer with a gradual refractive index based on the refractive index of the red fluorescent material, so that the fluorescence can be better emitted from the medium and the luminous efficiency is higher.

[0019] 3. The present invention uses solder and silver paste to bond the red ceramic layer and the reflective substrate, which has high connection strength, good stability, excellent service performance, and is suitable for industrial application. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the present invention or the technical solutions of the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0021] Figure 1 This is a schematic diagram of the packaging structure disclosed in the present invention.

[0022] In the figure: 1-transparent medium layer; 2-optical adhesive connection layer; 3-red ceramic layer; 4-welding layer; 5-reflective substrate. DETAILED DESCRIPTION

[0023] The specific implementation of the present invention is briefly described below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0024] Figure 1 The preferred embodiments of the present invention are shown and analyzed in detail.

[0025] Example 1

[0026] like Figure 1 A reflective red fluorescent ceramic packaging structure for laser display is shown, comprising a transparent medium layer 1, an optical adhesive connection layer 2, a red ceramic layer 3, a welding layer 4 and a reflective substrate 5. The welding layer 4, the red ceramic layer 3, the optical adhesive connection layer 2 and the transparent medium layer 1 are sequentially placed inside the reflective substrate 5 from bottom to top, the red ceramic layer 3 is connected to the reflective substrate 5 through the welding layer 4, and the transparent medium layer 1 is combined with the red ceramic layer 3 through the optical adhesive connection layer 2.

[0027] The transparent medium layer 1 is an aluminum oxide single crystal, with a refractive index of 1.77 at 800nm ​​and a transmittance of 85%. The optical adhesive connection layer 2 has a refractive index of 1.80 at 800nm ​​and a transmittance of 98%. The red ceramic layer 3 is an oxide system, with a refractive index of 1.83 at 800nm ​​and an emission peak wavelength of 625nm. The welding layer 4 is a solder. The reflective substrate 5 is an aluminum plate, with a reflectivity of 90% at 800nm.

[0028] In this packaging structure, the shear strength between the transparent medium layer 1 and the red ceramic layer 3 is 6Mpa through the use of the optical adhesive connection layer 2; the shear strength between the red ceramic layer 3 and the reflective substrate 5 is 75Mpa through the use of the welding layer 4. This structure is applied to the laser display system. Under the irradiation of blue laser, the fluorescence conversion efficiency of the reflective red fluorescent ceramic packaging structure is 255lm / W, and the blue light saturation power density is 25W / mm 2 .

[0029] Example 2

[0030] like Figure 1 A reflective red fluorescent ceramic packaging structure for laser display is shown, comprising a transparent medium layer 1, an optical adhesive connection layer 2, a red ceramic layer 3, a welding layer 4 and a reflective substrate 5. The welding layer 4, the red ceramic layer 3, the optical adhesive connection layer 2 and the transparent medium layer 1 are sequentially placed inside the reflective substrate 5 from bottom to top, the red ceramic layer 3 is connected to the reflective substrate 5 through the welding layer 4, and the transparent medium layer 1 is combined with the red ceramic layer 3 through the optical adhesive connection layer 2.

[0031] The transparent medium layer 1 is alumina ceramic, with a refractive index of 1.76 at 800nm ​​and a transmittance of 80%. The optical adhesive connection layer 2 has a refractive index of 1.77 at 800nm ​​and a transmittance of 95%. The red ceramic layer 3 is a nitride system, with a refractive index of 1.78 at 800nm ​​and an emission peak wavelength of 655nm. The welding layer 4 is silver paste. The reflective substrate 5 is an aluminum plate, with a reflectivity of 85% at 800nm.

[0032] In this packaging structure, the shear strength between the transparent medium layer 1 and the red ceramic layer 3 is 3Mpa through the use of the optical adhesive connection layer 2; the shear strength between the red ceramic layer 3 and the reflective substrate 5 is 35Mpa through the use of the welding layer 4. This structure is applied to the laser display system. Under the irradiation of blue laser, the fluorescence conversion efficiency of the reflective red fluorescent ceramic packaging structure is 245lm / W, and the blue light saturation power density is 15W / mm 2 .

[0033] The above description of the disclosed embodiments enables those skilled in the art to implement and use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit and scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest range consistent with the principles and novel features disclosed herein.

Claims

1. A reflective red fluorescent ceramic packaging structure for laser display, characterized in that: The invention comprises a transparent medium layer (1), an optical glue connection layer (2), a red ceramic layer (3), a welding layer (4) and a reflective substrate (5); wherein the welding layer (4), the red ceramic layer (3), the optical glue connection layer (2) and the transparent medium layer (1) are sequentially arranged inside the reflective substrate (5); the red ceramic layer (3) is connected to the reflective substrate (5) via the welding layer (4); and the transparent medium layer (1) is combined with the red ceramic layer (3) via the optical glue connection layer (2).

2. A reflective red fluorescent ceramic packaging structure for laser display according to claim 1, characterized in that: The transparent medium layer (1) is one of aluminum oxide ceramics and aluminum oxide single crystals, with a refractive index of 1.76 to 1.77 at 800 nm and a transmittance of 80 to 85%.

3. The reflective red fluorescent ceramic packaging structure for laser display according to claim 1, characterized in that: The refractive index of the optical adhesive connection layer (2) at 800 nm is 1.77-1.80, and the transmittance is 95-98%.

4. The reflective red fluorescent ceramic packaging structure for laser display according to claim 3, characterized in that: The shear strength of the optical adhesive connection layer (2) is 3 to 6 MPa.

5. The reflective red fluorescent ceramic packaging structure for laser display according to claim 1, characterized in that: The red ceramic layer (3) is one of an oxide and a nitride system; and has a refractive index of 1.78 to 1.83 at 800 nm.

6. The reflective red fluorescent ceramic packaging structure for laser display according to claim 5, characterized in that: The red ceramic layer (3) has an emission peak wavelength of 625-655 nm.

7. The reflective red fluorescent ceramic packaging structure for laser display according to claim 1, characterized in that: The welding layer (4) is made of solder or silver paste, and has a shear strength of 35 to 75 MPa.

8. The reflective red fluorescent ceramic packaging structure for laser display according to claim 1, characterized in that: The reflective substrate (5) is an aluminum plate, and its reflectivity at 800 nm is 85-90%.

9. The reflective red fluorescent ceramic packaging structure for laser display according to claim 1, characterized in that: The reflective red fluorescent ceramic packaging structure has a fluorescence conversion efficiency of 245-255 lm / W, and a blue light saturation power density of 15-25 W / mm 2 .

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