Laser-based light source and surface mount device

Abstract

The utility model relates to a laser-based light source and a surface mounting device. The laser-based light source includes a material disposed on a package base adjacent to the laser diode chip and an optical element coupled to the material. The optical elements are aligned to receive electromagnetic radiation from the laser diode chip. The optical element includes a wavelength converting material and is configured to receive at least a portion of the electromagnetic radiation emitted by the laser diode chip. The reflective material surrounds the sides of the optical element.

Description

Technical Field

[0001] The present utility model relates to a laser-phosphor integrated light source, and more particularly, to a laser-based light source and a surface mount device. Background Art

[0002] Due to the high efficiency, long life, low cost, and non-toxicity provided by solid-state lighting technology, light-emitting diodes (LEDs) have rapidly become the lighting technology of choice. An LED is a two-lead semiconductor light source typically based on a p-i-n junction diode that emits electromagnetic radiation when activated. The emission of an LED is spontaneous and is typically in a Lambertian pattern. When a suitable voltage is applied to the leads, electrons and holes recombine within the device, releasing energy in the form of photons. This effect is known as electroluminescence, and the color of the light is determined by the bandgap of the semiconductor.

[0003] By combining GaN-based LEDs with wavelength-converting materials such as phosphors, solid-state white light sources have been achieved. This technology of using GaN-based LEDs and phosphor materials to generate white light is now illuminating the world around us due to its many advantages such as low energy consumption, long life, good physical robustness, small size, and fast switching speed compared to incandescent light sources. Light-emitting diodes are now widely used in fields such as aviation lighting, automotive headlights, advertising, general lighting, traffic signals, and camera flashes. LEDs allow for the development of new text, video displays, and sensors, and their high switching rate is also useful in advanced communication technologies.

[0004] Although useful, according to the present utility model described in the following disclosure, LEDs still have limitations that are desired to be overcome. Summary of the Utility Model

[0005] The present utility model provides a device and method for integrating a white electromagnetic radiation source using a combination of a laser diode excitation source based on gallium- and nitrogen-containing materials and a light-emitting source based on phosphor materials. In the present utility model, a purple, blue, or other wavelength laser diode light source based on gallium- and nitrogen-containing materials is tightly integrated with a phosphor material (such as a yellow phosphor) to form a compact, high-brightness, and efficient white light source. In one example, the source can be provided for dedicated applications as well as general applications, etc.

[0006] According to one embodiment, a laser-based light source includes: a package base; a laser diode chip coupled to the package base, the laser diode chip being configured to output a laser beam of electromagnetic radiation from an output facet; the laser diode chip being configured to emit the electromagnetic radiation of a first wavelength; a material coupled to the package base and disposed on the package base adjacent to the laser diode chip, the material having a reflective surface; an optical element directly coupled to the top surface of the material, wherein a groove extends between a portion of the material and a portion of the optical element, the groove being aligned with the laser diode chip to receive the electromagnetic radiation from the laser diode chip, and the material being configured to direct at least a portion of the electromagnetic radiation in the groove into the optical element, the optical element including a wavelength conversion material configured to convert at least a portion of the electromagnetic radiation in the laser beam having the first wavelength into a second wavelength longer than the first wavelength; and a reflective material surrounding the side surface of the optical element, the reflective material being configured to reflect a portion of the electromagnetic radiation incident on the side surface of the optical element, wherein the optical element is configured to emit light from the top surface, the light including a first portion having the first wavelength and a second portion having the second wavelength.

[0007] In one embodiment, the laser-based light source further includes one or more additional laser diode chips and one or more additional grooves, each of the one or more additional laser diode chips being aligned with one of the additional grooves, wherein the one or more additional laser diode chips are configured to emit the electromagnetic radiation of the first wavelength.

[0008] In another embodiment, the laser-based light source further includes one or more additional laser diode chips and one or more additional grooves, each of the one or more additional laser diode chips being aligned with one of the additional grooves, wherein at least one of the one or more additional laser diode chips is configured to emit the electromagnetic radiation of a second wavelength different from the first wavelength.

[0009] In another embodiment, the groove is formed in the top of the material and extends from the side surface of the material, the groove reflecting at least a portion of the electromagnetic radiation in an upward direction toward the optical element.

[0010] In another embodiment, the material is thermally conductive and the material includes silicon (Si), silicon carbide (SiC), germanium (Ge), gallium arsenide (GaAs), sapphire, ceramic aluminum nitride (AlN), ceramic aluminum oxide (Al2O3), ceramic boron nitride (BN), aluminum (Al), or copper (Cu), and the reflective surface includes a reflective coating on the material.

[0011] In another embodiment, the wavelength conversion material is dispersed throughout the optical element.

[0012] In another embodiment, the upper portion of the optical element includes an optical homogenizer configured to improve the color uniformity of light emitted from the top surface of the optical element.

[0013] In another embodiment, at least one of the side, top, and bottom of the groove is covered with a reflective coating.

[0014] In another embodiment, a gap extends between at least some sides of the optical element and the reflective material.

[0015] In another embodiment, the laser-based light source further includes a scattering material in the groove, the scattering material in the groove being configured to scatter at least a portion of the electromagnetic radiation from the laser diode chip into the optical element.

[0016] In another embodiment, the groove includes sidewalls having a flat plane or sidewalls having a curved cross-section.

[0017] In another embodiment, the reflective material includes a reflective coating on the inner wall of the reflective material.

[0018] In yet another embodiment, the optical element includes at least one of a scattering feature, a diffraction feature, or a photonic crystal structure configured to provide color uniformity of light emitted from the top surface of the optical element.

[0019] According to another embodiment, a Surface Mount Device (SMD) includes a laser-based light source as described herein.

[0020] According to another embodiment, a laser-based light source includes: a package base; a laser diode chip coupled to the package base, the laser diode chip being configured to output a laser beam of electromagnetic radiation from an output facet; the laser diode chip being configured to emit electromagnetic radiation of a first wavelength; a material coupled to the package base and disposed on the package base adjacent to the laser diode chip, the material having a reflective surface; an optical element directly coupled to the top surface of the material; an optical waveguide having one end aligned with the output facet of the laser diode chip and the other end aligned with the optical element, the optical waveguide being configured and arranged to guide at least a portion of the electromagnetic radiation from the laser diode chip to the optical element, wherein the optical element includes a wavelength conversion material and is configured to receive at least a portion of the electromagnetic radiation emitted into the optical element, the wavelength conversion material being configured to convert at least a portion of the electromagnetic radiation having the first wavelength in the laser beam into a second wavelength longer than the first wavelength; and a reflective material surrounding the side surfaces of the optical element, the reflective material being configured to reflect a portion of the electromagnetic radiation incident on the side surfaces of the optical element, wherein the optical element is configured to emit light from the top surface, the light including a first portion having the first wavelength and a second portion having the second wavelength.

[0021] In one embodiment, the laser-based light source further includes a second laser diode chip, a second optical waveguide, and a groove extending between a portion of the material and a portion of the optical element, wherein the optical waveguide is aligned with a first end of the groove, and the second optical waveguide is aligned with a second end of the groove, the second optical waveguide being configured and arranged to guide a second electromagnetic radiation from the second laser diode chip to the groove in the optically transparent material.

[0022] In another embodiment, the material is thermally conductive and the material includes silicon (Si), silicon carbide (SiC), germanium (Ge), gallium arsenide (GaAs), sapphire, ceramic aluminum nitride (AlN), ceramic aluminum oxide (Al2O3), ceramic boron nitride (BN), aluminum (Al), or copper (Cu), and the reflective surface includes a reflective coating on the material.

[0023] In another embodiment, the wavelength conversion material is dispersed throughout the optical element.

[0024] In another embodiment, an upper portion of the optical element includes an optical homogenizer configured to improve color uniformity of the light emitted from the top surface of the optical element.

[0025] In another embodiment, a gap extends between at least some side surfaces of the optical element and the reflective material.

[0026] In another embodiment, the laser-based light source further includes a groove extending between a portion of the material and a portion of the optical element, and a scattering material in the groove, the scattering material in the groove being configured to scatter electromagnetic radiation from the laser diode chip into the optical element.

[0027] In yet another embodiment, the optical element includes at least one of a scattering feature, a diffraction feature, or a photonic crystal structure configured to provide color uniformity of the light emitted from the top surface of the optical element.

[0028] According to another embodiment, a surface mount device (SMD) includes a laser-based light source as described herein.

[0029] A further understanding of the nature and advantages of the present utility model can be realized by referring to the later part of the specification and the drawings. Description of the Drawings

[0030] Figures 1A to 1D is a simplified cross-sectional view of an integrated phosphor laser-based light source according to some embodiments of the present utility model.

[0031] Figure 2 is according to an embodiment of the present utility model Figures 1A to 1D a simplified top view of an integrated phosphor laser-based light source in one of the figures.

[0032] Figure 3 is a simplified perspective view of an integrated phosphor laser-based light source according to another embodiment of the present utility model.

[0033] Figure 4 is according to an embodiment of the present utility model Figure 3 a simplified cross-sectional perspective view of an integrated phosphor laser-based light source.

[0034] Figure 5 is a simplified perspective view of a material having a groove formed on the top surface according to an embodiment of the present utility model.

[0035] Figure 6 is a simplified perspective view of a material having a groove formed on the top surface according to another embodiment of the present utility model.

[0036] Figures 7A to 7F is a simplified diagram showing a process for forming a portion of an integrated phosphor laser-based light source according to an embodiment of the present utility model.

[0037] Figures 8A to 8B is a simplified diagram showing a process for forming a part of an integrated phosphor laser-based light source according to an embodiment of the present utility model.

[0038] Figures 9A to 9C is a simplified diagram of a laser-based light source with an integrated phosphor according to another embodiment of the present utility model.

[0039] Figures 10A to 10C is a simplified diagram of a laser-based light source with an integrated phosphor according to another embodiment of the present utility model.

[0040] Figures 11A to 11B is a simplified diagram of a laser-based light source with an integrated phosphor according to another embodiment of the present utility model.

[0041] Figures 12A to 12B is a simplified diagram showing a Figures 11A to 11B light guide and groove of a laser-based light source with an integrated phosphor according to an embodiment of the present utility model in a bottom view.

[0042] Figure 13 is a simplified diagram of a light guide structure according to an embodiment of the present utility model.

[0043] Figures 14A to 14E is a simplified diagram showing a process for forming a part of a laser-based light source with an integrated phosphor according to an embodiment of the present utility model.

[0044] Figures 15A to 15B is a simplified diagram showing a process for forming a groove at the bottom of an optically transparent material according to an embodiment of the present utility model.

[0045] Figure 16 is a simplified diagram of a metallization pattern on the bottom of an optically transparent material according to an embodiment of the present utility model.

[0046] Figures 17A to 17B is a simplified diagram of a laser-based light source with an integrated phosphor according to another embodiment of the present utility model.

[0047] Figures 18A to 18B is a simplified diagram showing a Figures 11A to 11B light guide and groove of a laser-based light source with an integrated phosphor according to an embodiment of the present utility model in a bottom view.

[0048] Figures 19 to 21 is a simplified cross-sectional view of a package of a laser-based light source with an integrated phosphor according to some embodiments of the present utility model.

[0049] Figures 22A to 22B is a simplified perspective view of a package of a laser-based light source with an integrated phosphor according to another embodiment of the present utility model.

[0050] Figures 23A to 23B is a simplified cross-sectional view and a plan view of a laser-based light source according to some embodiments of the present utility model.

[0051] Figures 24A to 24D is a simplified cross-sectional view of an optical element in a laser-based light source that can be used according to some embodiments of the present utility model.

[0052] Figures 25A to 25B is a simplified cross-sectional view and partial sectional view of a laser-based light source according to some embodiments of the present utility model.

[0053] Figures 26A to 26B is a simplified cross-sectional view and partial sectional view of a laser-based light source according to some embodiments of the present utility model.

[0054] Figures 27A to 27B is a simplified cross-sectional view and partial sectional view of a laser-based light source according to some embodiments of the present utility model.

[0055] Figures 28A to 28B is a simplified cross-sectional view and plan view of a laser-based light source according to some embodiments of the present utility model.

[0056] Figures 29A to 29C is a simplified cross-sectional view, perspective view, and sectional view of a laser-based light source according to some embodiments of the present utility model.

[0057] Figures 30A to 30B is a simplified cross-sectional view and plan view of a laser-based light source according to some embodiments of the present utility model.

[0058] Figures 31A to 31B is a simplified sectional view of a laser-based light source according to some embodiments of the present utility model.

[0059] Figures 32A to 32C is a simplified cross-sectional view, perspective view, and sectional view of a laser-based light source according to some embodiments of the present utility model.

[0060] Figures 33A to 33B is a simplified cross-sectional view and plan view of a laser-based light source according to some embodiments of the present utility model.

[0061] Figures 34A to 34D is a simplified perspective view and sectional view of a laser-based light source and components according to some embodiments of the present utility model.

[0062] Figures 35A to 35B is a simplified perspective view and sectional view of a laser-based light source according to some embodiments of the present utility model.

[0063] Figures 36A to 36B is a simplified perspective view and sectional view of a laser-based light source according to some embodiments of the present utility model.

[0064] Figures 37A to 37C is a simplified perspective view of a laser-based light source and various component structures according to some embodiments of the present utility model.

[0065] Figures 38A to 38C is a simplified perspective view of a laser-based light source and various component structures according to some embodiments of the present utility model.

[0066] Figures 39A to 39C is a simplified perspective view of components of a laser-based light source according to some embodiments of the present utility model.

[0067] Figures 40A to 40C is a simplified perspective view of components of a laser-based light source according to some embodiments of the present utility model.

[0068] Figure 41 is a simplified perspective view of components of a laser-based light source according to embodiments of the present utility model.

[0069] Figures 42A to 42B is a simplified perspective view of a part of components of a laser-based light source according to some embodiments of the present utility model.

[0070] Figures 43A to 43B is a simplified perspective view of a part of components of a laser-based light source according to some embodiments of the present utility model.

[0071] Figure 44 is a simplified perspective view of components of a laser-based light source according to embodiments of the present utility model.

[0072] Figures 45A to 45B is a simplified perspective view of a part of components of a laser-based light source according to some embodiments of the present utility model.

[0073] Figure 46 includes a simplified perspective view and an exploded view of components of a laser-based light source according to embodiments of the present utility model. Detailed Embodiments

[0074] The present utility model provides a method and a device for emitting white electromagnetic radiation by using a combination of a laser diode excitation source based on gallium- and nitrogen-containing materials and a light-emitting source based on phosphor materials. In the present utility model, a purple, blue, or other wavelength laser diode light source based on gallium- and nitrogen-containing materials is tightly integrated with a phosphor material to form a compact, high-brightness, and efficient white light source.

[0075] The use of the present utility model can achieve additional benefits superior to the prior art. Specifically, the present utility model realizes a cost-effective white light source. In a specific embodiment, this optical device can be manufactured in a relatively simple and cost-effective manner. Depending on the implementation, the present device and method can be manufactured using conventional materials and / or methods by those of ordinary skill in the art. In some embodiments of the present utility model, the gallium- and nitrogen-containing laser diode source is based on C-plane gallium nitride material, while in other embodiments, the laser diode is based on non-polar or semi-polar gallium and gallium nitride materials. In one embodiment, the white light source is configured as a chip on submount (CoS) with an integrated phosphor on a secondary submount to form a chip and phosphor on submount (CPoS) white light source.

[0076] In various embodiments, the laser device and the phosphor device are mounted on a common support member with or without an intermediate secondary submount, and the phosphor material operates in a transmission mode or a reflection mode to produce a laser-based light source that emits white light. By way of example only, the present utility model can be applied to, for example, white light illumination, white spot illumination, flashlights, automotive headlights, all-terrain vehicle illumination; light sources for recreational sports such as cycling, surfing, running, racing, rowing; light sources for drones, aircraft, robots, other mobile or robotic applications; autonomous devices such as land, sea or air vehicles and technologies, security, defense applications, countermeasures, multicolor illumination, illumination for tablets, medical, metrology, beam projectors and other displays; high-intensity lamps, spectroscopy, entertainment, theater, music and concerts, analysis, fraud detection and / or authentication, tools, water treatment, laser dazzlers, aiming, communication, transformation, transportation, leveling, curing and other chemical processes, heating, cutting and / or ablation, pumping other optical devices, other optoelectronic devices and related applications, and light source illumination, etc.

[0077] Figure 1A is a simplified cross-sectional view of a laser-based light source with an integrated phosphor according to an embodiment of the present utility model. The light source includes a laser diode chip 1 disposed on a package base such that the facet is positioned to emit light into a cavity or groove formed in the top surface of material 2 and / or formed in the bottom surface of optically transparent material 3. Alternatively, the light can be directly emitted into the optically transparent material 3. The laser diode chip 1 can include one or more laser diodes, and the light can be, for example, a laser beam with a wavelength in the blue or other color region. The light can be injected directly from the laser diode chip 1 or via an optical waveguide.

[0078] In some embodiments, the encapsulation base can be a printed circuit board (PCB). In other embodiments, the encapsulation base can be the bottom of a semiconductor package, which is configured to conduct heat from the laser diode chip 1 and the material 2 to the underlying structure, such as solder, metal core PCB, heat sink, etc. The encapsulation base can also include a metal block (e.g., Cu or Al), other electroplated metals, or a composite material of a ceramic material (e.g., AlN, Al 2 O 3 ) and metal. In other embodiments, the encapsulation base can be a metal plate (e.g., Cu or Al) and form part of a metal core PCB, such as a chip on board (COB).

[0079] In embodiments where the laser diode chip 1 emits light into the groove, the groove can form an air gap between the material 2 and the optically transparent material 3. The top surface of the material 2 and / or the interior of the groove can be covered with a reflective coating to direct and / or reflect light upward. For example, the reflective coating can be silver (Ag) or aluminum (Al), and if the surface is smooth, the reflective coating can be deposited as a flat specular reflection film, or if the surface is rough, the reflective coating can be deposited as a rough film that produces diffuse reflection.

[0080] The material 2 directs and / or reflects at least a portion of the light from the laser diode chip 1 in the upward direction towards the optically transparent material 3. The material 2 can have high thermal conductivity to conduct heat from the optically transparent material 3 and / or the wavelength conversion material 4 to the encapsulation base. In some embodiments, the material 2 can include silicon (Si), silicon carbide (SiC), germanium (Ge), gallium arsenide (GaAs), sapphire, ceramic aluminum nitride (AlN), ceramic aluminum 2 O 3 ) oxide, ceramic boron nitride (BN), aluminum (Al), copper (Cu), or other thermally conductive materials.

[0081] If the material 2 is Si, the groove can be etched with KOH to produce angled sidewalls. Many variations in the groove shape are possible. Figure 6 An example of a groove with a narrow neck that opens into a polygon is provided. In some embodiments, the optically transparent material 3 can have a shape similar to the groove. For example, Figure 6 the profile of the optically transparent material 3 includes a polygon shape similar to the groove. In some embodiments, the groove can be partially or completely filled with a diffusive volume scatterer (e.g., TiO 2 or Al 2 O 3 particles) in a low refractive index matrix such as glass, epoxy resin, or silicone.

[0082] The optically transparent material 3 can be optically transparent and thermally conductive. Example materials include single crystal SiC, sapphire, diamond, and transparent crystals from the garnet or spinel groups. The optically transparent material 3 allows light to be transmitted from the laser diode chip 1 to the wavelength conversion material 4 and conducts heat from the wavelength conversion material 4 to the material 2. The optically transparent material 3 can scatter light incident from other components. The top and bottom surfaces of the optically transparent material 3 can be smooth or rough. The rough surface serves the purpose of scattering light and can help to produce good color uniformity of the light emitted from the top surface of the wavelength conversion material 4. In one embodiment, the thickness of the optically transparent material 3 can be between about 100 μm and 250 μm, or between about 20 - 50% of the lateral dimension between about 300 μm and 1000 μm. The shape of the optically transparent material 3 as seen from a top view is not limited and can be square, rectangular, hexagonal, octagonal, circular, or any other shape.

[0083] The wavelength conversion material 4 down-converts all or a portion of the light from the laser diode chip 1. The wavelength conversion material 4 can be formed and / or configured according to any of the embodiments described herein. In an example, the wavelength conversion material 4 can be Ce-doped YAG. In some embodiments, the wavelength conversion material 4 can have voids or inclusions of other materials with different refractive indices that cause light scattering. The wavelength conversion material 4 can be a single crystal or sintered smaller particles. In some embodiments, the wavelength conversion material 4 can be a Ce-doped YAG / sapphire eutectic crystal. In one embodiment, the thickness of the wavelength conversion material 4 can be between about 50 μm and 800 μm, and the lateral dimension can be between about 300 μm and 1000 μm. The shape of the wavelength conversion material 4 as seen from a top view is not limited and can be square, rectangular, hexagonal, octagonal, circular, or any other shape.

[0084] The reflective material 5 reflects light incident from the sides of the optically transparent material 3 and the wavelength conversion material 4. The reflective material 5 can cover a part or all of the sides of the optically transparent material 3 and the wavelength conversion material 4 that can emit light. Example shapes of the reflective material 5 are as Figures 1B to 1C shown. If the light from the laser diode chip 1 is directly injected into the optically transparent material 3, the reflective material 5 can be omitted from the region where the light from the laser diode chip 1 injects the light into the optically transparent material 3. The reflective material 5 can be a diffusive volume scatterer (e.g., TiO 2 or Al 2 O 3 particles) in a low refractive index matrix such as glass, epoxy resin, or silicone. The reflective material 5 can also be a thin film coating (e.g., SiO 2 / Ag or Ag). If the reflective material 5 is a diffusive volume scatterer, its lateral thickness can be between about 50 μm and 500 μm, and if it is a thin film coating, it can be between about 50 nm and 10 μm. The height of the reflective material 5 can be approximately equal to the thickness of the optically transparent material 3 plus the thickness of the wavelength conversion material 4.

[0085] Figure 2 is a Figures 1A to 1D simplified top view of a laser-based light source with an integrated phosphor according to one embodiment of the present invention. In this example, the reflective material 5 surrounds the sides of the wavelength conversion material 4.

[0086] Figure 3 is a simplified perspective view of a laser-based light source with an integrated phosphor according to another embodiment of the present invention. In this example, the reflective material 5 is offset with respect to the material 2 and extends over a portion of the laser diode chip 1. Additionally, the shape of the wavelength conversion material 4 is different from that of the material 2. This can be seen more clearly in Figure 4 the cross-sectional view of Figure 4 which shows a groove formed in the top of the material 2, with the optically transparent material 3 and the wavelength conversion material 4 disposed above the groove. Figure 5 is a simplified perspective view of the material 2 with a groove formed in the top surface according to one embodiment.

[0087] Figures 7A to 7F is a simplified diagram showing a process for forming a portion of a laser-based light source with an integrated phosphor according to an embodiment of the present invention. Figure 7A shows the laser diode chip 1 and the material 2 assembled onto a package base. The laser diode chip 1 and the material 2 can be coupled to the package base using, for example, a soldering process. The material 2 has a groove formed in the top surface, and the light-emitting aperture of the laser diode chip 1 is aligned with the groove such that the light emitted from the laser diode chip 1 enters the groove.

[0088] Figures 7B to 7C shows a partially scribed sheet including an optically transparent material layer and a wavelength conversion material layer. Figure 7B is a plan view of the partially scribed sheet, and Figure 7C is a perspective view. The optically transparent material layer and the wavelength conversion material layer can be bonded using an adhesive. In one embodiment, the adhesive can be optically transparent and can produce a bond line thin enough to effectively conduct heat between the optically transparent material and the wavelength conversion material. Example adhesives include epoxy resin, silicone, glass, spin-on glass, or materials formed by a sol-gel process. Preferred properties of the adhesive include high thermal conductivity, optical transparency, good adhesion, and stability under long-term exposure to high temperature and optical flux.

[0089] As Figures 7B to 7C shown, the sheet of composite material can be diced into a desired shape. In this example, the sheet is diced into an octagon. This requires multiple cuts at different angles. The octagon does not utilize the sheet area as effectively as a square, but the octagon is close to circular and may be desirable for some applications.

[0090] Figures 7D to 7E shows a reflective material 5 formed around the sides of an octagonal optically transparent material 3 and wavelength conversion material 4 (“octagonal material”). The reflective material 5 can be a diffusive volume scatterer. After dicing, and while the octagonal materials are still mounted on the dicing carrier or tape, or after removing the octagonal materials and reassembling them on a new carrier at a desired spacing, the reflective material 5 can be dispensed around the octagonal materials. In one embodiment, the reflective material 5 can be dispensed or otherwise deposited in the gaps between an array of octagonal materials. The reflective material 5 can be cured using heat treatment and ensured to adhere to the octagon if necessary. Alternatively, the reflective material 5 can be deposited on an array of octagonal shapes and subsequently removed by a planarization process, such as milling, grinding, or, if the reflective material 5 is still in liquid or paste form, with a squeegee. A dicing process can be used to divide the octagonal materials surrounded by the reflective material 5.

[0091] Figure 7F shows the assembly of the octagonal materials surrounded by the reflective material 5 on the laser diode chip 1 and material 2. The material for attachment can be an optically transparent material, such as epoxy, silicone, glass, spin-on glass, or a material formed by a sol–gel process. Alternatively, the material for attachment can be solder or a similar material where the mating surfaces are metallized. In this case, the metallization can be added to the bottom surface of the reflective material 5 and / or the optically transparent material 3 in a pattern corresponding to the mating surface on the material 2. The metallization can be used as a reflector. In one embodiment, the metallization can include SiO 2 / Ag / TiW / Au. Solder can be included in the metallization, in which case the stack can include SiO 2 / Ag / TiW / AuSn.

[0092] Figures 8A to 8B is a simplified diagram showing a process for forming a portion of a laser-based light source for an integrated phosphor according to an embodiment of the present invention. These diagrams are similar to Figure 7A and Figure 7F , except that the grooves in the material 2 have different shapes and the metallization is added to the optically transparent material 3 in a different pattern. Other steps can correspond to Figures 7B - 7E , and are not shown separately.

[0093] Figures 9A to 9C is a simplified diagram of a laser-based light source with an integrated phosphor according to another embodiment of the present invention. The structure of this embodiment is similar to Figures 7A to 7F the structure of the embodiment shown in

[0094] In Figures 9A to 9C the example shown in

[0095] Figures 10A to 10C is a simplified diagram of a laser-based light source with an integrated phosphor according to another embodiment of the present invention. This embodiment is similar to Figures 9A to 9C the embodiment of

[0096] Figures 11A to 11B is a simplified diagram of a laser-based light source with an integrated phosphor according to another embodiment of the present invention. Figure 11B Similar to Figure 11A except that the reflective material 5 has been removed to show the light guide 1L aligned with the grooves in the optically transparent material 3. Figures 12A to 12B is a simplified diagram showing a bottom view of the light guide 1L and the grooves in the optically transparent material 3. The light guide 1L guides the light from the laser diode chip 1 to the grooves in the optically transparent material 3. The laser diode chip 1, the material 2, the optically transparent material 3, the wavelength conversion material 4, and the reflective material 5 may be similar in other respects to the corresponding features described with respect to Figures 1A to 1D above.

[0097] In this embodiment, the optical waveguide 1L guides the light from the laser diode chip 1 into the groove in the optically transparent material 3. The light is injected into the groove, where it is transmitted to the wavelength conversion material 4. The top surface of the material 2 may be covered with a reflective material that reflects the light upward through the optically transparent material 3.

[0098] The groove may be formed in the bottom surface of the optically transparent material 3. The groove may have a U-shape, V-shape, trench shape, or any other shape. The groove may extend partially through the optically transparent material 3. The groove may be aligned with the optical waveguide 1L or may be at an angle with respect to the optical axis of the optical waveguide 1L. The surface of the groove may be smooth or rough.

[0099] Figure 13 is a simplified diagram of an optical waveguide structure according to an embodiment of the present invention. The optical waveguide structure includes an optical waveguide 1L (or waveguide) and a frame. In some embodiments, the optical waveguide 1L may be tapered with a rectangular cross-section, or in other embodiments, the optical waveguide 1L may have a different cross-section including a circular shape. In some embodiments, the optical waveguide 1L may have different taper angles, including no taper. The optical waveguide 1L may include an optical fiber. The structure providing the optical waveguide 1L may provide mechanical support and / or assistance in the assembly of a laser-based light source incorporating a phosphor. The optical waveguide 1L may include a low refractive index material (cladding) surrounding a core material. The cladding may be formed by depositing, for example, MgF 2 onto a glass core.

[0100] Figures 14A to 14E is a simplified diagram showing a process for forming a portion of a laser-based light source incorporating a phosphor according to an embodiment of the present invention. In Figure 14A , the material 2 is disposed on a package base. The material 2 may be welded or glued to the package base using an adhesive. In Figure 14B , an optical waveguide structure having the optical waveguide 1L is disposed on the material 2. The optical waveguide structure may be welded or glued to the material 2 using an adhesive such as epoxy or silicone. Alternatively, the optical waveguide structure may be part of an array of sheet-like similar structures bonded to a sheet of the material (sheet of the material 2). In this embodiment, a splitting process may be used to form the optical waveguide structure and the material 2 and then assemble them onto the package base. In either embodiment, the optical waveguide structure may be formed from a glass substrate using, for example, known processes that may include deposition, patterning, etching, and splitting.

[0101] In Figure 14C , the optically transparent material 3 and the wavelength conversion material 4 are assembled onto the material 2. The optically transparent material 3 and the wavelength conversion material 4 may be formed in a manner shown in the above Figures 7B to 7C , except that in this embodiment, it may be as inFigures 15A to 15B A groove is formed at the bottom of the optically transparent material as shown. The groove in the bottom of the optically transparent material 3 is aligned with the end of the light guide 1L. The adhesive for attachment can be optically transparent, such as epoxy resin, silicone, glass, spin-on glass or a material formed by a sol-gel process. Alternatively, the material for attachment can be solder or a similar material, where the mating surfaces are metallized. In this case, metallization can be added to the bottom surface of the optically transparent material 3, as Figure 16 shown. The metallization can be used as a reflector. In one embodiment, the metallization can include SiO 2 / Ag / TiW / Au. Solder can be included in the metallization, in which case the stack can include SiO 2 / Ag / TiW / AuSn.

[0102] In Figure 14D , a reflective material 5, such as a diffusive volume scatterer, is formed around the sides of the optically transparent material 3 and the wavelength conversion material 4. In Figure 14E , the laser diode chip 1 is assembled onto the package base. The laser diode chip 1 can be coupled to the package base using, for example, a soldering process. The light emitting aperture of the laser diode chip 1 is aligned with the light guide 1L such that the light emitted from the laser diode chip 1 can be guided to the groove.

[0103] Figures 17A to 17B is a simplified diagram of an integrated phosphor-based laser light source according to another embodiment of the present invention. The structure of this embodiment is similar to the structure of the embodiment shown in Figures 14A to 14E , except that this embodiment includes a first laser diode chip 1a and a second laser diode chip 1b, and the light guide structure includes separate light guides 1L for each laser diode chip. The light guides 1L can be aligned with the opposite ends of a single groove as shown in Figure 17B , where the reflective material 5 is removed for clarity. In another embodiment, each light guide can be aligned with a separate groove.

[0104] In Figures 17A to 17B the example shown, both laser diode chips 1a, 1b inject light into the same groove. In some embodiments, the light from each of the laser diode chips 1a, 1b can have substantially similar wavelengths (e.g., 440 - 460 nm), or the light from each of the laser diode chips 1a, 1b can have different wavelengths (e.g., 450 nm and 590 - 650 nm, 450 nm and 850 nm, 450 nm and 905 nm, 450 nm and 940 nm, 450 nm and 980 nm, 450 nm and 405 nm or any other wavelengths). Figures 18A - 18BIt is a simplified top view showing the light guides 1L at each end of the groove in the optically transparent material 3 according to one embodiment.

[0105] Figures 19 to 21 It is a simplified cross-sectional view of a laser-based light source package integrated with a phosphor according to some embodiments of the present invention. In Figure 19 a seal is formed between the window or cover and the package sidewall using an adhesive (such as epoxy resin or solder). The window can be glass or another optically transparent material that allows light to pass through. The window, package sidewall, and package base can provide an implicit seal for the laser diode chip 1, material 2, optically transparent material 3, wavelength conversion material 4, and reflective material 5.

[0106] In Figure 20 a seal is formed between the window or cover and the wall of the metal can using an adhesive (such as glass solder, brazing material, or metal solder). A seal between the metal can and the package base can be formed by raised welding. The wall of the metal can can block stray light from the laser diode 1. The window, wall, and package base can provide an implicit seal for the laser diode chip 1, material 2, optically transparent material 3, wavelength conversion material 4, and reflective material 5.

[0107] In Figure 21 a seal is formed between the metal flange and the reflective material 5 using an adhesive (such as epoxy resin or solder). The reflective material 5 and the wavelength conversion material 4 can be non-porous, enabling an airtight seal for the laser diode chip 1, material 2, and optically transparent material 3.

[0108] Figures 22A to 22B It is a simplified perspective view of a laser-based light source package integrated with a phosphor according to another embodiment of the present invention. In this example, a light guide structure, such as described above with respect to Figures 11A - 11B forms part of the package housing. A seal is formed between the metal flange and the light guide structure using an adhesive (such as epoxy resin or solder). A seal is formed between the metal flange and the sidewall using an adhesive (such as epoxy resin, solder, or raised welding).

[0109] Figure 23ASimplified cross-sectional view of a laser-based light source according to some embodiments of the present invention. The light source includes a laser diode 1 (or laser diode chip) disposed on a packaging base such that the facet is positioned to emit light into a cavity or groove formed in the top surface of a material 2 (e.g., a thermally conductive material) and / or formed in the bottom surface of an optical element 4 and / or in a cavity between the material 2 and the optical element 4. Alternatively, the light can be directly emitted into the optical element 4. The laser diode 1 can be formed according to any of the embodiments described herein. The light source 1 can include one or more laser diodes, and the light can be, for example, a laser beam having a wavelength in the blue or another color region. The light can be directly injected from the laser diode 1 or via an optical waveguide.

[0110] In some embodiments, the packaging base can be a printed circuit board (PCB). In other embodiments, the packaging base can be the bottom of a semiconductor package configured to conduct heat from the laser diode 1 and the material 2 to a structure below, such as solder, a metal core PCB, a heat sink, etc. The packaging base can also include a metal block (e.g., Cu or Al), other electroplated metals, or a composite material of a ceramic material (e.g., AlN, Al 2 O 3 ) that can include metal. In other embodiments, the packaging base can be a metal plate (e.g., Cu or Al) and form part of a metal core PCB, such as a chip on board (COB).

[0111] In embodiments where the laser diode 1 emits light into the groove, the groove can constitute an air gap between the material 2 and the optical element 4. The top surface of the material 2 and / or at least a portion of the interior of the groove can be covered with a reflective coating to direct and / or reflect the light upward. For example, the reflective coating can include silver (Ag) or aluminum (Al). Alternatively or additionally, the reflective coating can include a covering dielectric layer for environmental protection and / or include a dielectric stack, such as one or more layers of SiO 2 and / or Ta 2 O 5 to increase the reflectivity. If the surface is smooth, the reflective coating can be deposited as a flat specular reflection film, or if the surface is rough, the reflective coating can be deposited as a rough film that produces diffuse reflection.

[0112] The material 2 directs and / or reflects at least a portion of the light from the laser diode 1 in an upward direction toward the optical element 4. The material 2 can have high thermal conductivity to conduct heat from the optical element 4 to the packaging base. In some embodiments, the material 2 can include silicon (Si), silicon carbide (SiC), germanium (Ge), gallium arsenide (GaAs), sapphire, ceramic aluminum nitride (AlN), ceramic aluminum 2 O 3)), ceramic boron nitride (BN), aluminum (Al), copper (Cu), or other thermally conductive materials.

[0113] If Material 2 is Si, grooves can be etched with KOH to produce angled sidewalls. Many variations in the groove shape are possible. Figure 6 An example of a groove with a narrow neck that opens into a polygon is provided. In some embodiments, the optical element 4 can have a shape similar to the groove. For example, Figure 6 includes a profile of an optically transparent material 3 having a polygonal shape similar to the groove. In some embodiments, the groove can be partially or fully filled with a diffusive volume scatterer (e.g., TiO in a low refractive index matrix such as glass, epoxy, or silicone 2 or Al 2 O 3 particles).

[0114] The optical element 4 can include a wavelength conversion material that down-converts all or a portion of the light from the laser diode 1. The wavelength conversion material can be uniformly dispersed throughout the optical element 4. The optical element 4 can be formed and / or configured according to any of the embodiments described herein. In one example, the optical element 4 can include Ce-doped YAG. In another example, the optical element 4 can include Ce-doped YAG doped with sapphire in a eutectic crystal. In some embodiments, the optical element 4 can have voids or inclusions of other materials with different refractive indices that cause light scattering. The optical element 4 can be a single crystal or sintered smaller particles. In one embodiment, the thickness of the optical element 4 can be between about 50 - 800 μm or greater, and the lateral dimension can be between about 300 - 1000 μm. The shape of the optical element 4 as seen from a top view is not limited and can be square, rectangular, hexagonal, octagonal, circular, or any other shape.

[0115] The reflective material 5 reflects light incident from the sides of the optical element 4. The reflective material 5 can cover a portion or all of the sides of the optical element 4 that can emit light. Example shapes of the reflective material 5 are as Figures 1B to 1C shown. If the light from the laser diode 1 is directly injected into the optical element 4, the reflective material 5 can be omitted from the region where the light is injected into the optical element 4 from the laser diode 1. The reflective material 5 can be a diffusive volume scatterer (e.g., TiO in a low refractive index matrix such as glass, epoxy, or silicone 2 or Al 2 O 3 particles). The reflective material 5 can also be a thin film coating on the sidewalls of the optical element 4 (e.g., SiO 2 / Ag or Ag). If the reflective material 5 is a diffusive volume scatterer, its lateral thickness can be between about 20 - 500 μm, and if it is a thin film coating, it can be between about 50 nm and 10 μm. The height of the reflective material 5 can be approximately equal to the thickness of the optical element 4.

[0116] Figure 23B is according to an embodiment of the present utility model Figure 23A Simplified plan view of a laser-based light source. In this example, the reflective material 5 surrounds the side surface of the optical element 4.

[0117] Figures 24A to 24D is a simplified cross-sectional view of an optical element that can be used in any laser-based light source described herein according to some embodiments of the present utility model. In Figure 24A the example, the optical element 4 includes a wavelength conversion material. The thermal conductivity of the wavelength conversion material can be sufficient to conduct heat from the optical element 4 to the underlying material 2. In some embodiments including a cavity between the optical element 4 and the material 2, the thermal conductivity of the wavelength conversion material can be sufficient to conduct heat from the optical element 4 and around the cavity to the underlying material 2.

[0118] In Figure 24B the example, the optical element 4 includes a wavelength conversion material 4a covering an optically transparent thermal conductor 4b. The optically transparent thermal conductor 4b can be disposed between the wavelength conversion material 4a and the material 2. The optically transparent thermal conductor 4b can be configured to allow light to pass from the laser diode 1 and the material 2 to the wavelength conversion material 4a, and conduct heat from the wavelength conversion material 4a to the material 2 and the package base. The optically transparent thermal conductor 4b can also be configured to scatter light incident from other elements to improve the color uniformity of the light emitted from the top surface of the optical element 4. Light scattering can occur at one or more interfaces of the optically transparent thermal conductor 4b and / or within the body of the optically transparent thermal conductor 4b.

[0119] In Figure 24C the example, the optical element 4 includes a wavelength conversion material 4a and at least one optical homogenizer 4c. The at least one optical homogenizer 4c is configured to improve the color uniformity of the light emitted from the top surface of the optical element 4. The optical homogenizer 4c can be optically transparent (e.g., glass or sapphire) or at least partially translucent (e.g., Al 2 O 3 ceramics). In some embodiments, the top surface of the optical homogenizer 4c can be rough and / or include optical scattering features.

[0120] In Figure 24DIn the example of, the optical element 4 includes a wavelength conversion material 4a disposed between an optically transparent thermal conductor 4b and at least one optical homogenizer 4c. The optically transparent thermal conductor 4b may include features similar to those described with respect to Figure 24B and at least one optical homogenizer 4c may include features similar to those described with respect to Figure 24C Description.

[0121] Figures 25A to 25B is a simplified cross-sectional view and partial sectional view of a laser-based light source according to some embodiments of the present invention. The optical element 4 includes a wavelength conversion material 4a disposed on an optically transparent thermal conductor 4b. Alternatively, the optical element may include Figures 24A to 24D Any other configuration shown in. In this particular example, the wavelength conversion material 4a may include features similar to those described with respect to Figure 24A and the optically transparent thermal conductor 4b may include features similar to those described with respect to Figure 24B Description. Figure 25A And Figure 25B The embodiments of also include an optical waveguide 1L. The optical waveguide 1L may have features similar to those of the optical waveguide discussed with reference to FIGS. 11 to 14. The optical waveguide 1L is configured to direct light from the laser diode 1 to the optical element 4 or the space or groove between the material 2 and the optical element 4. In embodiments including a space or groove, at least a portion of the optical waveguide 1L may be disposed in the space or groove. In some embodiments, the optical waveguide 1L may have light extraction features along at least a portion of its length, such as the portion in the space or groove.

[0122] In Figure 25A In the example of, a cross-sectional view showing the relative spatial arrangement of various elements of a display embodiment is shown. The light emitted by the laser diode 1 is transmitted to the transparent thermal conductor by the optical waveguide 1L.

[0123] In Figure 25B In the example of, a cross-sectional view showing the relative spatial arrangement of various elements of a display embodiment is shown. As can be seen from this figure, the wavelength conversion material 4a and the optically transparent thermal conductor 4b may have a polygonal shape surrounded by a reflective material 5.

[0124] Figures 26A to 26B is a simplified cross-sectional view and partial sectional view of a laser-based light source according to some embodiments of the present invention. This embodiment is similar to Figures 25A to 25B except that the optical waveguide 1L is arranged at an angle with respect to the laser diode 1 and the optical element 4 (or the optically transparent thermal conductor 4b in this example). Other angles may be used in other embodiments, and the specific angle is not limited.

[0125] In Figure 26AIn the example of, a cross-sectional view showing the relative spatial arrangement of various elements of the display embodiment is shown, including the angle of the optical waveguide 1L extending between the laser diode 1 and the optical element 4.

[0126] In Figure 26B the example of, a cross-sectional view showing the relative spatial arrangement of various elements of the display embodiment is shown. As described above, the optical waveguide 1L can be configured to guide light from the laser diode 1 to the space or groove between the optical element 4 or the material 2 and the optical element 4.

[0127] Figures 27A to 27B is a simplified cross-sectional view and partial cross-sectional view of a laser-based light source according to some embodiments of the present invention. The optical element 4 includes a wavelength conversion material 4a disposed on the optically transparent thermal conductor 4b. The wavelength conversion material 4a can include features similar to those described with respect to Figure 25A and the optically transparent thermal conductor 4b can include features similar to those described with respect to Figure 25B described. Figure 27A and Figure 27B The embodiments of also include an optical waveguide 1L. The optical waveguide 1L can have features similar to the optical waveguide discussed with reference to FIGS. 11 to 14. In the illustrated embodiment, there is a cavity between the material 2 and the optically transparent thermal conductor 4b, and the cavity is formed as a space or groove in the bottom surface of the optically transparent thermal conductor 4b. A portion of the optical waveguide 1L is placed in the groove. The optical waveguide 1L can have light extraction features along a portion of its length, such as the portion in the groove.

[0128] In Figure 27A the example of, a cross-sectional view showing the relative spatial arrangement of various elements of the display embodiment is shown, including the optical waveguide 1L extending into the cavity between the material 2 and the optical element 4.

[0129] In Figure 27B the example of, a cross-sectional view showing the relative spatial arrangement of various elements of the display embodiment is shown. The figure also shows the optical waveguide 1L extending into the cavity.

[0130] Figures 28A to 28B is a simplified cross-sectional view and plan view of a laser-based light source according to some embodiments of the present invention. In the illustrated embodiment, a gap extends between the optical element 4 and the reflective material 5. The reflective material 5 reflects light incident from the side of the optical element 4 and covers most or all of the side region of the optical element 4 that can emit light. In some embodiments, the reflective material 5 may not cover the portion of the optical element 4 where the laser diode 1 injects light into the optical element 4.

[0131] In Figure 28AIn the example, a cross-sectional view showing the relative spatial arrangement of various elements of the display embodiment is presented, including the gap between the optical element 4 and the reflective material 5.

[0132] In Figure 28B the example, a top-down view showing the relative spatial arrangement of various elements of the display embodiment with respect to the Figure 28A orientation shown in

[0133] Figures 29A to 29C are a simplified side view, perspective view, and cross-sectional view of a laser-based light source according to some embodiments of the present invention. In the illustrated embodiment, the gap extends between the optical element 4 and the reflective material 5. In some embodiments, for example, due to tolerances, there may be a nominal small gap between the optical element 4 and the reflective material 5. From an optical perspective, it may be desirable for the gap to be less than, for example, up to about 40 μm, up to about 50 μm, up to about 60 μm or greater. The gap can have other dimensions depending on, for example, various materials, shapes, manufacturing processes, and / or assembly techniques.

[0134] In some embodiments, the reflective material 5 is formed separately, for example, using a sintering process, a high-temperature ceramic process, or a glass particle process, and subsequently assembled with the optical element 4, and may include a gap. In some embodiments, the reflective material 5 has diffusive properties. In some embodiments, the reflective material 5 is formed of a material (such as TiO 2 or Al 2 O 3 ) co-sintered with a transparent low-refractive-index material (such as glass, SiO 2 or BaTiO 3 particles). In some embodiments, the reflective material 5 can be formed separately (e.g., by a sintering process) and then assembled with the optical element 4. In other embodiments, the reflective material 5 can include an element having a reflective film or coating on the inner wall (or walls) facing the optical element 4. As an example, the reflective material 5 can be a silicon element having holes produced using an etching process (such as reactive ion etching), and the silicon element can include a reflective coating (such as an Ag coating) on the inner wall (or walls) facing the optical element 4.

[0135] In Figures 29A to 29B the example, a side view and a perspective view showing the relative spatial arrangement of various elements of the display embodiment are presented respectively. In Figure 29C the example, a cross-sectional view showing the cavity in which light is directly or through the light guide 1L emitted onto the upper surface of the material 2 according to one embodiment is presented. In other embodiments, light can be emitted into the optical element 4, into the cavity in the bottom surface of the optical element 4, or into the cavity between the material 2 and the optical element 4.

[0136] Figures 30A to 30B is a simplified cross-sectional view and a plan view of a laser-based light source according to some embodiments of the present invention. In the illustrated embodiment, element 2b is included. Element 2b can be a reflective element. The laser diode 1 injects light into the cavity between the material 2, the element 2b, and the optical element 4. A variety of devices for injecting light from different positions are possible. For example, light can be injected directly from the laser diode 1 or via an optical waveguide 1L (not shown), and can extend at least partially into the cavity. For example, the cavity can be formed by a groove in the top surface of the material 2 and a through-hole in the reflective element 2b.

[0137] In some embodiments, the material 2 redirects a portion of the incident light in the upward direction. Additionally, the reflective element 2b can also be used to redirect a portion of the incident light in the upward direction. The reflective element 2b can also serve as a mechanical support for the optical element 4 and / or the reflective material 5. The reflective element 2b can also be configured to conduct heat from the optical element 4 to the package base via the material 2.

[0138] Figures 31A to 31B is a simplified cross-sectional view of a laser-based light source according to some embodiments of the present invention. In the illustrated embodiment, different-shaped elements 2b are shown. In some embodiments, the element 2b can be formed by, for example, wafer manufacturing techniques, including lithography, etching, and deposition; photochemical etching, including using different mask designs on the top and bottom ("half-etching"); or stamping / pressing of metal sheets or other forming. Materials for the reflective element 2b can include, for example, Si, Ge, sapphire, SiC, glass, and various metals. In some embodiments, the material has a reflective coating.

[0139] In Figures 31A to 31B the example of, a cross-sectional view showing the relative spatial arrangement of various elements of an embodiment including the element 2b is shown. In Figure 31A the example of, the element 2b has a relatively flat shape with a through-hole for light to pass through. In Figure 31B the example of, the element 2b also extends around the side of the reflective material 5.

[0140] Figures 32A to 32C is a simplified cross-sectional view, a perspective view, and a cross-sectional view of a laser-based light source according to some embodiments of the present invention. In the illustrated embodiment, another element 2b is shown. As Figure 32C shown, the element 2b has a stepped feature that provides a gap between the top surface of the element 2b and the laser diode 1. In some embodiments, the gap can be used, for example, for wire bonding on the top surface of the laser diode 1.

[0141] Figures 33A to 33BSimplified cross-sectional and plan views of a laser-based light source according to some embodiments of the present invention. In the illustrated embodiment, element 24 is included. The laser diode 1 injects light into the cavity between the material 2, element 24, and the optical element 4. A variety of devices for injecting light from different positions are possible. The light can be injected directly from the laser diode 1 or via, for example, an optical waveguide 1L (not shown) that is at least partially located in the cavity. For example, the cavity between the material 2, element 24, and the optical element 4 can be formed by a groove in the top surface of the material 2. Element 24 can be an element or material that redirects a portion of the incident light in the upward direction and can be formed as a topological feature of the material 2. In some embodiments, element 24 is different from the material 2.

[0142] In some embodiments, the material 2 includes a stepped feature to redirect a portion of the incident light in the upward direction, and element 24 is also used to redirect a portion of the incident light in the upward direction.

[0143] Figures 34A to 34D Simplified perspective and cross-sectional views of a laser-based light source and components according to some embodiments of the present invention. In the illustrated embodiment, the material 2 is shown to have a groove or cavity and a through-hole. Element 24 can also be included on top of the material 2. Element 24 can couple the material 2 to the optical element 4. In some embodiments, a groove is formed within the material 2. Light from the laser diode 1 is injected into the groove. The inner walls of the groove, including the top and bottom, can be coated with a high reflectivity coating to minimize absorption losses. In some embodiments, the material 2 can include a bottom member having a groove and an element 24 that engages to form the groove.

[0144] Figure 34A and Figure 34C Simplified perspective and cross-sectional views of a laser-based light source according to some embodiments of the present invention. In the illustrated embodiment, the optical element 4 and the reflective material 5 are disposed on top of the element 24 and the material 2. The laser diodes 1 are disposed on each side such that light is injected into each end of the groove. The material 2 includes a stepped feature within the groove to redirect a portion of the incident light in the upward direction. These figures illustrate how the light emitted from the laser diode 1 is guided upward through the holes in the element 24 and into the optical element 4.

[0145] In Figure 34B the example of, a cross-sectional view showing the relative spatial arrangement of the various elements of the illustrated embodiment is shown. In this example, a stepped or ramp-shaped feature is included in the groove to facilitate guiding the light upward through the hole and into the optical element 4.

[0146] In Figure 34DIn the example, a perspective view showing the relative spatial arrangement of various elements of the display embodiment is presented, including how the top surface of element 24 forms the base or support for an optical element 4 (not shown).

[0147] Figures 35A to 35B FIG. 4 is a simplified perspective view and cross-sectional view of a laser-based light source according to some embodiments of the present invention. In the illustrated embodiment, a package configuration is shown. According to some embodiments of the present invention, the package structure houses the laser-based light source, and the package structure includes a lid and a window. The lid can be made of metal, ceramic, plastic, or other materials, and the window can be a transparent material. In this example, the lid is square (a square can include a rectangle), with rounded corners and a ridge around the bottom. Other shapes can be used according to the embodiments described herein. In some embodiments, a seal between the window and the lid is formed using, for example, a frit, a brazing material, solder, an epoxy resin, or another sealing material. A seal between the lid and the package base can be formed, for example, using a bump weld, a frit, a brazing material, solder, an epoxy resin, or other methods.

[0148] In some embodiments, the window includes glass or other transparent materials. The shape of the window can be flat or include topological features such as curves. The window can include a lens. For example, the lens can be flat or have a topological structure such as a laterally varying thickness. The window can have an optical coating applied to one or both sides, such as an anti-reflection coating or a wavelength filter. Additionally, in some embodiments, the window can have diffractive or scattering features formed on one or both sides or over the entire surface.

[0149] In Figure 35A the example, a perspective view showing the relative spatial arrangement of various elements of the display embodiment is presented, and in Figure 35B the example, a cross-sectional view showing the relative spatial arrangement of various elements of an embodiment of the display including the exemplary laser-based light source described herein is presented. Other laser-based light sources can be used with the package.

[0150] Figures 36A to 36Bis a simplified perspective view and cross-sectional view of a laser-based light source according to some embodiments of the present invention. In the illustrated embodiment, a packaging configuration is shown. According to some embodiments of the present invention, the packaging structure houses the laser-based light source, and the packaging structure includes a cover having an opening. Thus, in this embodiment, the top surface of the optical element 4 can be exposed through the opening. A portion of the reflective material 5 can also be exposed through the opening. The cover can be made of metal, ceramic, plastic, or other materials. Seals between the cover and the element 24, between the element 24 and the optical element 4, between the cover and the frame, and between the frame and the packaging base can be formed, for example, with glass frit, brazing material, solder, epoxy resin, or other materials. In some embodiments, the cover can include a frame in a single piece.

[0151] In Figure 36A the example of, a perspective view showing the relative spatial arrangement of the various elements of the display embodiment is shown, and in Figure 36B the example of, a cross-sectional view showing the relative spatial arrangement of the various elements of the display embodiment including the exemplary laser-based light source described herein is shown. An enlarged view of a portion of the laser-based light source is shown, showing the material 2, the element 24, the optical element 4, and the reflective material 5. Other laser-based light sources can be used with the packaging.

[0152] Figures 37A to 37C is a simplified perspective view of a laser-based light source and various component structures according to some embodiments of the present invention. In the illustrated embodiment, an optical waveguide is formed in or on a substrate or a packaging base. The light source 1 is mounted on a substrate having an emission hole, for example, at or near the substrate, and the light source 1 injects light into the optical waveguide. The optical waveguide can be routed under the optical element 4 and the reflective material 5, and the optical waveguide can have the characteristic of extracting light upward and injecting light through the bottom surface of the optical element 4 in this region. In some embodiments, the optical waveguide can be formed, for example, by thin film deposition techniques or by sol gel processes.

[0153] In Figure 37A the example of, a perspective view showing the relative spatial arrangement of the various elements of the display embodiment is shown. In Figures 37B to 37C the example of, a perspective view showing the relative spatial arrangement of the various elements of the substrate and the optical waveguide is shown, without the laser diode 1, the optical element 4, and the reflective material 5. In Figure 37C the example of, a close-up perspective view showing pads that can be included on the substrate for attaching the optical element 4 is shown. The optical waveguide can be divided into multiple parts to increase and / or improve the uniformity of light extraction into the optical element 4.

[0154] Figures 38A to 38Cis a simplified perspective view of a laser-based light source and various component structures according to some embodiments of the present invention. In the illustrated embodiment, the optical element 4 is located above the light source in the arrangement of the figure. For example, the light source may have two laser diodes or laser diode chips 1a and 1b mounted on a single secondary mount. Grooves in the bottom side of the optical element 4 or the optically transparent thermal conductor 4b and the reflective material 5 are aligned with the laser diode chips 1a and 1b and the reflective element to provide a gap during assembly. The top surface of the secondary mount corresponding to the bottom surface of the optically transparent thermal conductor 4b may have a reflective coating to direct light upward toward the optical element 4. In some embodiments, only one laser chip or more than two laser chips are mounted on the secondary mount, and the reflective element redirects the emitted light of all chips toward the optical element 4.

[0155] In Figure 38A the example of, a perspective view showing the relative spatial arrangement of various elements of the display embodiment is shown. In Figure 38B the example of, a perspective view of the bottom of the optically transparent thermal conductor 4b and the reflective material 5 is shown, showing the relative spatial arrangement of various elements of the embodiment including the grooves. In Figure 38C the example of, a perspective view of the secondary mount with the optical element 4 and the reflective material 5 removed is shown to show the relative spatial arrangement of various elements of the embodiment including the reflective element.

[0156] As discussed elsewhere herein, the material 2 can be configured to redirect a portion of the incident light from the light source 1 to the optical element 4. There are other elements that can also redirect light. For example, in some embodiments, an optical waveguide 1L present in the structure can direct at least a portion of the light from the laser diode 1 to the optical element 4. In some embodiments, there is a cavity in the structure between the material 2 and the optical element 4, and the shape of the cavity and the interface between the cavity and the optical element 4 can additionally or alternatively direct a portion of the light from the light source 1 in an upward direction to the optical element 4. In some embodiments, the optical element 4 has an interface between the wavelength conversion material 4a and the optically transparent thermal conductor 4b, and the interface can be configured to redirect light within the optical element 4.

[0157] Figures 39 to 45 are simplified perspective views of examples of the material 2 of a laser-based light source according to some embodiments of the present invention. The illustrated embodiments show examples that achieve light redirection and can be used to generate a more uniform illumination of the bottom of the optical element 4. In some embodiments, by redirecting a portion of the light from the light source 1 into the optical element 4 at a high angle with respect to the normal, the irradiance of the non-wavelength-converted light will be more uniform across the lateral cross-section of the optical element 4. This can result in an increase in the spatial color uniformity of the light exiting from the top surface of the optical element 4.

[0158] Figures 39A to 39C A simplified perspective view of an example of material 2 of a laser-based light source according to some embodiments of the present invention. The illustrated embodiment has a groove that advantageously redirects light from light source 1 to optical element 4 with high uniformity. The groove of the illustrated embodiment has a rectangular pattern layout, which is formed by, for example, standard crystallographic etching techniques for etching a silicon substrate. The illustrated embodiment provides a non-limiting example. Other groove arrangements may be considered. In some embodiments, the surface of the groove is smooth. In some embodiments, the surface of the groove has scattering and / or diffraction features. In some embodiments, the surface of the groove has or includes a photonic crystal structure. In some embodiments, the scattering and / or diffraction features are formed in a bottom layer material having a reflective thin film coating on top. In some embodiments, the scattering and / or diffraction features are formed on top of a smooth surface coated with a reflective coating, where a further coating with desired features is formed on top. For example, in some embodiments, a coating of high refractive index particles in a low refractive index binder is used. In some embodiments, a dielectric layer having features etched into its surface is used.

[0159] In Figure 39A the example of, material 2 includes a single groove to facilitate guiding light into optical element 4. Figure 39B The example of is similar, except that material 2 includes a plurality of offset grooves. Separate laser diodes 1 may be aligned with each groove. Figure 39C The example of is similar, except that the grooves are aligned. The grooves in these examples may be rectangular, for example, and may be well formed by crystal etching of silicon.

[0160] Figures 40A to 40CA simplified perspective view of an example of material 2 of a laser-based light source according to some embodiments of the present invention. The illustrated embodiment has a groove that advantageously redirects light from one or more light sources 1 to an optical element 4 with high uniformity. The groove of the illustrated embodiment has a layout with a curved cross-section. Compared to sidewalls composed of flat planes, the curved cross-section can propagate the reflected light over a wider angular range. The illustrated embodiment provides a non-limiting example. Other groove arrangements may be considered. In some embodiments, the surface of the groove is smooth. In other embodiments, the surface of the groove has scattering and / or diffraction features. In some embodiments, the surface of the groove has or includes a photonic crystal structure. In some embodiments, the scattering and / or diffraction features are formed in a base material having a reflective thin film coating on top. In some embodiments, the scattering and / or diffraction features are formed on a smooth surface and may be coated with a reflective coating and / or a coating having other desired features. For example, in some embodiments, a coating of high refractive index particles in a low refractive index binder may be used. In some embodiments, a dielectric layer having features etched into its surface may be used. The groove may include a cavity, as shown in Figure 40A the example of.

[0161] Figure 41 A simplified perspective view of an example of material 2 of a laser-based light source according to some embodiments of the present invention. The illustrated embodiment has a groove that advantageously redirects light from light source 1 to an optical element 4 with high uniformity. The illustrated groove has steps. For example, the steps can be formed by performing two or more etching processes using different mask layouts. The illustrated embodiment provides a non-limiting example. Other groove arrangements may be considered. For example, in some embodiments, one or more grooves may have more than one step. Additional grooves for multiple light source embodiments may be included.

[0162] Figures 42A to 42B A simplified perspective view of the groove sidewall profile in material 2 according to some embodiments of the present invention. As shown, in some embodiments, the groove sidewall profile is straight and has a slope. The slope can be any slope that allows for a desired improvement in the uniformity of the light injected into the optical element 4, which can result in an improved color uniformity of the light exiting from the top surface of the optical element 4.

[0163] Figures 43A to 43Bis a simplified perspective view of the groove sidewall profile in material 2 according to some embodiments of the present invention. As shown, in some embodiments, the groove sidewall profile is curved. Compared with a straight sidewall, the curvature can be various profiles sufficient to propagate reflected light within a wider angular range. Thus, the curved cross-section can contribute to improving the uniformity of light injected into the optical element 4, which can result in improved color uniformity of the light exiting from the top surface of the optical element 4. Although these examples illustrate grooves formed in the top surface of the material 2, alternative embodiments may include similar grooves formed in the bottom surface of the optical element 4.

[0164] Figure 44 is a simplified perspective view of an example of material 2 of a laser-based light source according to some embodiments of the present invention. The illustrated embodiment has a groove that can advantageously redirect light from the light source 1 to the optical element 4 with high uniformity. The groove of the illustrated embodiment has a scattering volume element. The scattering volume element is configured to scatter incident light from the laser diode 1 into the optical element 4. In some embodiments, the scattering volume element includes high refractive index particles in a low refractive index binder. In some embodiments, the low refractive index binder can have high refractive index particles. The scattering volume element can be formed by applying (e.g., dispensing) a substance in liquid or paste form, which can subsequently be cured to form a solid. In some embodiments, the scattering volume element is additionally or alternatively formed in a groove on the bottom surface of the optical element 4.

[0165] Figures 45A to 45B is a simplified perspective view of an example of material 2 of a laser-based light source according to some embodiments of the present invention. The illustrated embodiment has a groove that can advantageously redirect light from the light source 1 to the optical element 4 with high uniformity. The groove of the illustrated embodiment has a transparent or translucent optical element in the groove. One or more surfaces of the transparent or translucent optical element can have scattering features, diffraction features, or a photonic crystal structure. In some embodiments, the transparent or translucent optical element is attached to the groove, as shown. In some embodiments, the transparent or translucent optical element is additionally or alternatively attached to the bottom surface of the optical element 4 or formed within a groove on the bottom surface of the optical element 4. In some embodiments, the optical element can also act as a light guide 1L for injecting light from the light source 1 into the cavity between the material 2 and the optical element 4.

[0166] In Figure 45A example, the optical element does not extend beyond the groove. In Figure 45B example, the optical element extends beyond the groove. For example, if the optical element is used as a light guide 1L, it may be advantageous to extend beyond the groove.

[0167] Figure 46 A simplified perspective view and an exploded view of components of a laser-based light source according to an embodiment of the present invention are shown. In the illustrated embodiment, example diffraction or scattering features are shown. These features can be used to increase the color uniformity of the light exiting from the top surface of the optical element 4. In some embodiments, the top surface of the optically transparent thermal conductor 4b can include scattering features, diffraction features, or a photonic crystal structure, as shown, for example. These features can include air gaps or can be filled in whole or in part with a material having a refractive index different from one or more of the optically transparent thermal conductor 4b and the wavelength conversion material 4a.

[0168] In some embodiments, the scattering features, diffraction features, or photonic crystal structure can be formed at the interface between the wavelength conversion material 4a and the optically transparent thermal conductor 4b. In some embodiments, the scattering features, diffraction features, or photonic crystal structure are additionally or alternatively formed in the bottom surface of the wavelength conversion material 4a and / or the bottom surface of the optically transparent thermal conductor 4b. In some embodiments, the scattering features, diffraction features, or photonic crystal structure are additionally or alternatively formed in the bottom surface of the optical element 4. The scattering features, diffraction features, or photonic crystal structure formed in the bottom surface of the element can cover the entire bottom surface or a portion of the bottom surface. For example, these features can cover a portion of the bottom surface where light from one or more laser diodes 1 enters the optical element 4. In some embodiments, the scattering features, diffraction features, or photonic crystal structure are additionally or alternatively formed in the top surface of the optical element 4, the wavelength conversion material 4a, the optically transparent thermal conductor 4b, and / or the optical homogenizer 4c. Scattering features can also be formed inside the optical element 4 (including the wavelength conversion material 4a, the optically transparent thermal conductor 4b, and / or the optical homogenizer 4c (when present)). These features can be dispersed throughout the optical element 4 or they can be concentrated in a specific layer within the optical element 4. For example, the scattering features can be formed in a volume near the top and / or bottom of the optical element 4 or at the top and / or bottom of various regions of the optical element 4.

[0169] Many shapes, sizes, geometric features, and spacings can be used for the scattering features, diffraction features, or photonic crystal structure, and the shapes, sizes, and geometric features are not limited. In some embodiments, the size and spacing of the scattering features, diffraction features, or photonic crystal structure are close to the visible light wavelength, for example, 50 nm to 1000 nm.

[0170] In some embodiments, the pattern of the scattering features, diffraction features, or photonic crystal structure is regular, as Figure 46as shown in the examples. In some embodiments, the scattering features, diffraction features, or photonic crystal structures are defined by holography, conventional lithography, nanoimprint lithography, or similar processes. In some embodiments, the patterns of the scattering features, diffraction features, or photonic crystal structures are irregular or random. In some embodiments, for example, the features are defined by nanosphere lithography. In some embodiments, the distribution pattern of the scattering features, diffraction features, or photonic crystal structures is the result of roughness caused, for example, by mechanical processes or chemical etching processes. In some embodiments, lithography-defined masks are not used.

[0171] It should be understood that the number of laser diodes or chips used with each embodiment described herein is not limited. For example, any embodiment can be used with a single or multiple laser diode 1 configurations, as Figures 10A to 10B or Figures 34A to 35B as shown in the examples. Additionally, in some embodiments, one or more laser diodes 1 can emit within the blue wavelength range, purple wavelength range, infrared (IR) wavelength range, or a combination including different IR wavelengths. For example, some embodiments can include one or more laser diodes that emit within the blue wavelength range, one or more laser diodes that emit within a first IR wavelength range (e.g., 850 nm), and one or more laser diodes that emit within a first IR wavelength range (e.g., 905 nm). Other embodiments can include other various combinations of laser diodes of blue, purple, and IR wavelengths (e.g., the IR wavelengths can be 850 nm, 905 nm, 940 nm, 1300 nm, 1550 nm, or others).

[0172] The methods, systems, and devices discussed above are examples. Various configurations can appropriately omit, replace, or add various procedures or components. For example, in alternative configurations, the methods can be performed in a different order than described, and / or various stages can be added, omitted, or combined. Additionally, the features described with respect to certain configurations can be combined in various other configurations. Different aspects and elements of the configurations can be combined in a similar manner. Moreover, technology is evolving, and thus, many of the elements are examples and do not limit the scope of the present disclosure or the claims.

Claims

1. A laser-based light source, characterized in that The light source comprises: Package base; a laser diode chip coupled to the package base, the laser diode chip being configured to output a laser beam of electromagnetic radiation from an output facet; the laser diode chip being configured to emit the electromagnetic radiation at a first wavelength; a material coupled to the package base and disposed on the package base adjacent to the laser diode chip, the material having a reflective surface; an optical element directly coupled to a top surface of the material, wherein a groove extends between a portion of the material and a portion of the optical element, the groove is aligned with the laser diode chip to receive electromagnetic radiation from the laser diode chip, and the material is configured to direct at least a portion of the electromagnetic radiation in the groove into the optical element, the optical element comprising a wavelength conversion material configured to convert at least a portion of the electromagnetic radiation in the laser beam having a first wavelength to a second wavelength longer than the first wavelength; and a reflective material surrounding a side of the optical element, the reflective material being configured to reflect a portion of the electromagnetic radiation incident on the side of the optical element, wherein the optical element is configured to emit light from a top surface, the light comprising a first portion having the first wavelength and a second portion having the second wavelength.

2. The laser-based light source according to claim 1, characterized in that The light source further includes one or more additional laser diode chips and one or more additional grooves, each of the one or more additional laser diode chips being aligned with one of the additional grooves, wherein the one or more additional laser diode chips are configured to emit electromagnetic radiation at the first wavelength.

3. The laser-based light source of claim 1, wherein: The light source further includes one or more additional laser diode chips and one or more additional grooves, each of the one or more additional laser diode chips being aligned with one of the additional grooves, wherein at least one of the one or more additional laser diode chips is configured to emit electromagnetic radiation at the second wavelength different from the first wavelength.

4. The laser-based light source of claim 1, wherein: The grooves are formed in the top of the material and extend from the side surface of the material, the grooves reflecting at least a portion of the electromagnetic radiation in an upward direction towards the optical element.

5. The laser-based light source of claim 1, wherein: The material is thermally conductive and includes one of silicon (Si), silicon carbide (SiC), germanium (Ge), gallium arsenide (GaAs), sapphire, ceramic aluminum nitride (AlN), ceramic aluminum oxide (Al2O3), ceramic boron nitride (BN), aluminum (Al) and copper (Cu), and the reflective surface includes a reflective coating on the material.

6. The laser-based light source of claim 1, wherein: The wavelength converting material is dispersed throughout the optical element.

7. The laser-based light source of claim 1, wherein: An upper portion of the optical element includes an optical homogenizer configured to improve color uniformity of the light emitted from the top surface of the optical element.

8. The laser-based light source of claim 1, wherein: At least one of the side, top and bottom of the groove is covered by a reflective coating.

9. The laser-based light source of claim 1, wherein: Gaps extend between at least some of the sides of the optical element and the reflective material.

10. The laser-based light source of claim 1, wherein: The light source further includes a scattering material in the recess, the scattering material in the recess being configured to scatter at least a portion of the electromagnetic radiation from the laser diode chip into the optical element.

11. The laser-based light source of claim 1, wherein: The groove includes a side wall having a flat plane or a side wall having a curved cross-section.

12. The laser-based light source of claim 1, wherein: The reflective material includes a reflective coating on an inner wall of the reflective material.

13. The laser-based light source of claim 1, wherein: The optical element includes at least one of scattering features, diffractive features, and photonic crystal structures configured to provide color uniformity of the light emitted from the top surface of the optical element.

14. The laser-based light source of claim 13, wherein: The reflective material includes a reflective coating on an inner wall of the reflective material.

15. A surface mounted device, characterized in that: Comprising the laser-based light source of claim 1.

16. A laser-based light source, characterized in that The light source comprises: Package base; a laser diode chip coupled to the package base, the laser diode chip being configured to output a laser beam of electromagnetic radiation from an output facet; the laser diode chip being configured to emit the electromagnetic radiation at a first wavelength; a material coupled to the package base and disposed on the package base adjacent to the laser diode chip, the material having a reflective surface; an optical element coupled directly to the top surface of the material; a light guide having one end aligned with the output facet of the laser diode chip and another end aligned with the optical element, the light guide being configured and arranged to guide at least a portion of the electromagnetic radiation from the laser diode chip to the optical element, wherein the optical element comprises a wavelength conversion material and is configured to receive at least a portion of the electromagnetic radiation emitted into the optical element, the wavelength conversion material being configured to convert at least a portion of the electromagnetic radiation having a first wavelength in the laser beam into a second wavelength longer than the first wavelength; and a reflective material surrounding a side of the optical element, the reflective material being configured to reflect a portion of the electromagnetic radiation incident on the side of the optical element, wherein the optical element is configured to emit light from a top surface, the light comprising a first portion having the first wavelength and a second portion having the second wavelength.

17. The laser-based light source of claim 16, wherein: The light source further comprises a second laser diode chip, a second light guide, and a groove extending between a portion of the material and a portion of the optical element, wherein the light guide is aligned with a first end of the groove and the second light guide is aligned with a second end of the groove, and the second light guide is configured and arranged to guide second electromagnetic radiation from the second laser diode chip to the groove.

18. The laser-based light source of claim 16, wherein: The material is thermally conductive and includes one of silicon (Si), silicon carbide (SiC), germanium (Ge), gallium arsenide (GaAs), sapphire, ceramic aluminum nitride (AlN), ceramic aluminum oxide (Al2O3), ceramic boron nitride (BN), aluminum (Al) and copper (Cu), and the reflective surface includes a reflective coating on the material.

19. The laser-based light source of claim 16, wherein: The wavelength converting material is dispersed throughout the optical element.

20. The laser-based light source of claim 16, wherein: An upper portion of the optical element includes an optical homogenizer configured to improve color uniformity of the light emitted from the top surface of the optical element.

21. The laser-based light source of claim 16, wherein: Gaps extend between at least some of the sides of the optical element and the reflective material.

22. The laser-based light source of claim 16, wherein: The light source further includes a groove extending between a portion of the material and a portion of the optical element and a scattering material in the groove, the scattering material in the groove being configured to scatter the electromagnetic radiation from the laser diode chip into the optical element.

23. The laser-based light source of claim 16, wherein: The optical element includes at least one of scattering features, diffractive features, and photonic crystal structures configured to provide color uniformity of the light emitted from the top surface of the optical element.

24. A surface mounted device, characterized in that: Comprising the laser-based light source of claim 16.

Images