A laser illumination TO package structure based on fluorescence converter

Abstract

This invention discloses a laser lighting TO packaging structure based on a phosphor converter, relating to the field of laser lighting technology. The structure includes a TO base, a laser chip, a right-angled triangular prism, a phosphor converter, a reflecting prism, and a reflecting mirror. The TO base includes pins and a boss, with the laser chip soldered to the side of the boss. The right-angled triangular prism is positioned above the laser chip, with one right-angled face fixed to the side of the boss and the other right-angled face facing upwards, housing the phosphor converter. The reflecting prism is an irregularly shaped prism, mounted on the TO base via a support frame, and the reflecting mirror is fixedly mounted on the top of the boss. This invention utilizes the ease of shaping laser beams, and through a simple optical path design, splits the blue laser beam into two beams. While maintaining the total energy and laser spot size, it decomposes the laser spot into two beams with different irradiation directions, improving the laser tolerance of the phosphor converter without affecting its miniaturization.

Description

Technical Field

[0001] This invention relates to the field of laser lighting technology, and more specifically to a laser lighting TO packaging structure based on a phosphor converter. Background Technology

[0002] As a new generation of lighting technology, laser lighting technology uses laser light sources with excellent directional performance as the lighting source. It has the characteristics of strong penetration and long illumination distance, and has broad application prospects in fields such as military reconnaissance, security, and projection display. Its implementation schemes are generally divided into two types: one is to achieve white light illumination by exciting a yellow phosphor with a blue laser; the other is to achieve white light illumination by combining and mixing red, green, and blue primary color laser beams.

[0003] The basic principle of white light illumination via a phosphor converter is to use a blue laser to excite a yellow phosphor, producing yellow fluorescence. The remaining blue laser light mixes with the generated yellow fluorescence to produce white light. The main problem in this process is the weak laser tolerance of the yellow phosphor. The process of pump light irradiating the phosphor converter and being absorbed to produce fluorescence is usually accompanied by significant heat generation. Simultaneously, due to the small spot size and high energy density of the blue laser source, irradiation of the phosphor converter will cause a sharp, localized temperature rise, resulting in extremely uneven temperature distribution within the phosphor converter. This affects the performance of the phosphor converter and, in severe cases, can lead to its breakage. Increasing the laser spot size through beam expansion masks the advantages of miniaturization in laser illumination. Therefore, the overall solution must improve the functional capacity of the illumination component while maintaining a small laser spot size.

[0004] Currently, researchers and industry professionals largely focus on the power handling capacity of fluorescent converters, employing various methods to improve their thermal conductivity and suppress heat generation. These methods have evolved from the initial silica gel and phosphor approach to PiG fluorescent glass, fluorescent transparent ceramics, and fluorescent crystals, even leading to the development of complex multiphase fluorescent converter components. For example, Chinese invention patent CN117003558A discloses a relatively comprehensive high-performance fluorescent converter fabrication scheme, utilizing a fluorescent transparent ceramic technology platform, and covering component design and structural design. However, as a comprehensive device, laser lighting devices cannot be adequately improved by simply upgrading core components.

[0005] Some researchers have adopted a scheme similar to a color wheel, fixing the phosphor converter on a high-speed rotating disk. Through rapid mechanical movement, the position of the phosphor converter under laser irradiation constantly changes, thereby improving the laser load-bearing capacity of the phosphor converter. This is an effective method, but the mechanical components are large, the cost is high, and the requirements for the operating environment are also quite stringent. It is generally only used in fields such as laser projection displays and is difficult to promote in areas such as automotive lighting. Summary of the Invention

[0006] To address the aforementioned issues, this invention discloses a laser illumination TO packaging structure based on a phosphor converter. Utilizing the ease of shaping laser beams, the laser spot originally hitting one location on the phosphor converter is split into two with different irradiation directions, while maintaining the same total energy and laser spot size. This effectively improves the laser tolerance of the phosphor converter.

[0007] According to the present invention, a laser illumination TO packaging structure based on a phosphor converter is proposed, comprising a TO base, a laser chip, a right-angled triangular prism, a phosphor converter, a reflecting prism, and a reflecting mirror. The TO base includes pins and a boss, and the laser chip is soldered to the side of the boss of the TO base. The right-angled triangular prism is disposed above the laser chip, with one right-angled face fixed to the side of the boss and the other right-angled face facing upwards, where the phosphor converter is placed. The reflecting prism is an irregularly shaped prism, mounted on the TO base by a support frame. The reflecting prism cooperates with the right-angled triangular prism to split the pump light emitted by the laser chip into two parts: one part is directly incident on the lower surface of the phosphor converter, and the other part reaches the side of the phosphor converter after multiple reflections. The reflecting mirror is fixedly mounted on the top of the boss and disposed on the back side of the phosphor converter that receives the reflected light. After the reflected light is absorbed by the phosphor converter, the remaining light is reflected back to the phosphor converter by the reflecting mirror.

[0008] Preferably, the reflecting prism includes a semi-transparent and semi-reflective surface and two total reflection surfaces. The semi-transparent and semi-reflective surface of the reflecting prism is opposite to and parallel to the inclined surface of the right-angled triangular prism. The two total reflection surfaces are intersecting surfaces. The principle for setting the intersection angle is that the light can be horizontally output to the phosphor converter after being reflected by the semi-transparent and semi-reflective surface and the two total reflection surfaces. After the pump light emitted by the laser chip enters the reflecting prism, it is first split into two beams by the semi-transparent and semi-reflective surface. One beam passes through the right-angled triangular prism and reaches the lower surface of the phosphor converter. The other beam is reflected by the two total reflection surfaces of the reflecting prism and reaches the side of the phosphor converter.

[0009] Preferably, the phosphor converter is a YAG:Ce phosphor ceramic, and the Ce doping concentration is 0.01%-0.5%.

[0010] Preferably, the fluorescent converter is made by welding low-melting-point glass powder onto a right-angled triangular prism.

[0011] Compared with the prior art, the advantages of the laser illumination TO packaging structure based on a phosphor converter disclosed in this invention are:

[0012] This invention utilizes the easy shaping characteristic of laser beams. Through a simple optical path design, the blue laser beam is split into two beams. Without changing the total energy and laser spot size, the laser spot that originally hit one position on the phosphor converter is decomposed into two beams with different irradiation directions. This effectively reduces the power density per unit light-receiving area of ​​the phosphor converter, improves the laser tolerance of the phosphor converter, and does not affect the miniaturization of the phosphor converter. Attached Figure Description

[0013] To more clearly illustrate the technical solutions of the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0014] Figure 1 This is a front view of an embodiment of the present invention.

[0015] Figure 2 This is a right view of an embodiment of the present invention.

[0016] Figure 3 This is a schematic diagram of the optical path according to an embodiment of the present invention.

[0017] In the figure: 1-Reflecting prism; 2-Boss; 3-Support frame; 4-TO base; 5-YAG:Ce fluorescent ceramic; 6-Reflector; 7-Isosceles right-angled triangular prism; 8-Laser chip. Detailed Implementation

[0018] The specific embodiments of the present invention will be briefly described below with reference to the accompanying drawings. Obviously, the described embodiments are merely some, not all, embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0019] Figures 1-3 A preferred embodiment of the present invention is shown and analyzed in detail.

[0020] like Figure 1 , Figure 2 The illustrated laser illumination TO packaging structure based on a phosphor converter includes a TO base 4, a laser chip 8, an isosceles right-angled triangular prism 7, a YAG:Ce phosphor ceramic 5, a reflective prism 1, and a reflector 6.

[0021] The TO base 4 includes pins and bosses 2.

[0022] The laser chip 8 is soldered to the side of the boss 2 of the TO base 4.

[0023] The isosceles right-angled triangular prism 7 is made of K9 glass and is set above the laser chip 8. One right-angled face is glued to the side of the protrusion 2 of the TO base 4, and the other right-angled face is set upwards to place the YAG:Ce fluorescent ceramic 5. The emitted light from the laser chip 8 can reach the bottom surface of the YAG:Ce fluorescent ceramic 5 after passing through the isosceles right-angled triangular prism 7.

[0024] The YAG:Ce fluorescent ceramic 5 has a size of 1*1*1mm and a Ce doping concentration of 0.5%. It is soldered onto the isosceles right-angled triangular prism 7 using low-melting-point glass powder, and the solder does not cover the light-transmitting surface.

[0025] The reflecting prism 1 is an irregularly shaped hexagonal prism made of K9 glass. It is mounted on the TO base 4 via a support frame 3, and the reflecting prism 1 is bonded to the support frame 3. The reflecting prism 1 includes a semi-transparent and semi-reflective surface and two total reflection surfaces. The semi-transparent and semi-reflective surface of the reflecting prism 1 is opposite to and parallel to the inclined plane of the isosceles right-angled triangular prism 7. The semi-transparent and semi-reflective surface is achieved using an optical coating. The two total reflection surfaces are intersecting surfaces. The principle for setting the intersection angle is that light rays, after being reflected by the semi-transparent and semi-reflective surface and the two total reflection surfaces, can be horizontally output to the YAG:Ce fluorescent ceramic 5. The total reflection effect of the total reflection surface can be generated by coating or by the total reflection effect itself. If the total reflection effect is generated, the incident angle needs to reach or exceed the total reflection angle of the material. In this invention, the incident angle of the incident light rays on the total reflection surface is 45°, reaching the total reflection angle from K9 glass to air. Therefore, the total reflection is achieved by using the total reflection angle method. One of the total reflection surfaces is positioned opposite the semi-transparent and semi-reflective surface to receive the reflected light from the semi-transparent and semi-reflective surface. The light beam reflected by the two total reflection surfaces is perpendicular to the light output direction of the laser chip 8 and reaches the side of the YAG:Ce fluorescent ceramic 5. The support is made of glass and is bonded to the TO base 4.

[0026] The reflector 6 is fixedly mounted on the top of the boss 2, positioned on the back side of the YAG:Ce fluorescent ceramic 5 to receive reflected light. After the reflected light is absorbed by the YAG:Ce fluorescent ceramic 5, the remaining light is reflected back to the YAG:Ce fluorescent ceramic 5 by the reflector 6. The reflector 6 is made of K9 glass with aluminum plating, and its connection to the boss 2 of the TO base 4 is by adhesive bonding.

[0027] like Figure 3As shown, the pump light emitted by the laser chip 8 enters the reflecting prism 1 and is first split into two beams by the semi-transparent and semi-reflective surface. One beam passes through the isosceles right-angled triangular prism 7 and reaches the lower surface of the YAG:Ce fluorescent ceramic 5. The other beam is reflected by the two total reflection surfaces of the reflecting prism 1 and reaches the side of the YAG:Ce fluorescent ceramic 5. The light reflected by the total reflection surface to the YAG:Ce fluorescent ceramic 5 is absorbed by the YAG:Ce fluorescent ceramic 5, and the remainder is reflected by the reflecting mirror 6 and returns to the YAG:Ce fluorescent ceramic 5.

[0028] After completion, the device has a standard TO56 package size. Using the optical path structure of this invention, the power handling capability of the YAG:Ce phosphor ceramic 5 is increased by approximately two times, from 15W / m². 2 Rise to 30W / m 2 This improved the laser tolerance of the fluorescent converter.

[0029] The above description of the disclosed embodiments enables those skilled in the art to make and use the invention. Various modifications to these embodiments will be readily 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 invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A laser illumination TO packaging structure based on a phosphor converter, characterized in that, The system includes a TO base (4), a laser chip (8), a right-angled triangular prism, a phosphor converter, a reflecting prism (1), and a reflecting mirror (6). The TO base (4) includes pins and a boss (2). The laser chip (8) is soldered to the side of the boss (2) of the TO base (4). The right-angled triangular prism is positioned above the laser chip (8), with one right-angled face fixed to the side of the boss (2) and the other right-angled face facing upwards to hold the phosphor converter. The reflecting prism (1) is an irregularly shaped prism. The mirror is mounted on the TO base (4) by the support frame (3). The reflecting prism (1) cooperates with the right-angled triangular prism to split the pump light emitted by the laser chip (8) into two parts. One part is directly incident on the lower surface of the phosphor converter, and the other part reaches the side of the phosphor converter after multiple reflections. The reflecting mirror (6) is fixedly installed on the top of the boss (2) and is set on the back of the phosphor converter to receive the reflected light. After the reflected light is absorbed by the phosphor converter, the remainder is reflected back to the phosphor converter by the reflecting mirror (6).

2. The laser illumination TO packaging structure based on a phosphor converter according to claim 1, characterized in that, The reflecting prism (1) includes a semi-transparent and semi-reflective surface and two total reflection surfaces. The semi-transparent and semi-reflective surface of the reflecting prism (1) is opposite to the inclined surface of the right-angled triangular prism and remains parallel. The two total reflection surfaces are intersecting surfaces. The principle for setting the intersection angle is that the light can be horizontally output to the phosphor converter after being reflected by the semi-transparent and semi-reflective surface and the two total reflection surfaces. After the pump light emitted by the laser chip (8) enters the reflecting prism (1), it is first split into two beams by the semi-transparent and semi-reflective surface. One beam passes through the right-angled triangular prism and reaches the lower surface of the phosphor converter. The other beam is reflected by the two total reflection surfaces of the reflecting prism (1) and reaches the side of the phosphor converter.

3. The laser illumination TO packaging structure based on a phosphor converter according to claim 1, characterized in that, The phosphor converter is a YAG:Ce phosphor ceramic (5), and the Ce doping concentration is 0.01%-0.5%.

4. The laser illumination TO packaging structure based on a phosphor converter according to claim 3, characterized in that, The fluorescent converter is welded onto a right-angled triangular prism using low-melting-point glass powder.

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