Optical wavelength conversion device and light source

Abstract

The utility model relates to the technical field of lighting equipment, in particular to an optical wavelength conversion device and a light source, the optical wavelength conversion device is used for receiving laser and emitting fluorescence in a specified direction under the excitation action of the laser, and the optical wavelength conversion device comprises a substrate and a plurality of surface microstructures. The substrate has a thickness direction and comprises a first surface and a second surface, and the first surface and the second surface are located on the two sides of the substrate in the thickness direction. The plurality of surface microstructures are arranged on the first surface of the substrate, each surface microstructure is provided with a third surface, the third surface is inclined relative to the first surface, and the third surface is provided with a wavelength conversion layer, so that the third surface is used for absorbing laser to generate fluorescent light and reflecting the laser which is not absorbed; and the reflection direction of the laser which is not absorbed is consistent with a specified direction. Through the arrangement, reflected laser and excited fluorescence can be mixed together, Fresnel reflection of the laser on the surface of the device can be reduced, and meanwhile, the laser for exciting the fluorescence is increased.

Description

Technical Field

[0001] The present application relates to the technical field of lighting equipment, and in particular to a light wavelength conversion device and a light source. Background Art

[0002] In traditional laser headlights, blue lasers are used to excite fluorescent ceramics to generate fluorescence, which is then collected by subsequent collection devices to achieve laser headlight illumination. Figure 1 As shown in the figure, the blue laser is incident at an angle, and most of the blue laser light is excited to produce fluorescence, while a small portion is reflected by the surface of the fluorescent ceramic. The generated fluorescence is collected by the collecting device, realizing the illumination of the laser headlight. The incident blue laser light is specularly reflected by the surface of the fluorescent ceramic. The reflected blue laser light is transmitted from the other side and is concentrated by the subsequent collecting device. This causes a blue spot in the headlight, which seriously affects the quality of the laser headlight.

[0003] Currently, a common solution to this problem is to add a polarizing beam splitter prism in front of the collection device. This deflects the blue laser light reflected from the fluorescent ceramic piece in another direction, preventing it from entering the subsequent collection device. The excited fluorescent light can then pass through the polarizing beam splitter and, after passing through the subsequent collection device, project the light beam toward the ground. The polarizing beam splitter separates the reflected blue laser light from the excited fluorescent light, thereby reducing the impact of the reflected blue laser light on the laser headlights. However, the reflected blue laser light also affects the excitation efficiency of the fluorescent light, which can have a certain impact on the overall efficiency of the laser headlights. Utility Model Content

[0004] The present application provides a light wavelength conversion device and also provides a light source.

[0005] In a first aspect, the present application provides a light wavelength conversion device for receiving laser light and emitting fluorescence in a specified direction under the excitation of the laser light. The light wavelength conversion device includes a substrate and a plurality of surface microstructures. The substrate has a thickness direction and includes a first surface and a second surface, the first surface and the second surface being located on opposite sides of the substrate in the thickness direction. The plurality of surface microstructures are arranged on the first surface of the substrate, the surface microstructures having a third surface that is inclined relative to the first surface and provided with a wavelength conversion layer, so that the third surface is used to absorb the laser light to generate fluorescence and reflect the unabsorbed laser light, and the reflection direction of the unabsorbed laser light is consistent with the specified direction.

[0006] Optionally, in some embodiments, a plurality of surface microstructure arrays are arranged on the first surface of the substrate and protrude relative to the first surface.

[0007] Optionally, in some embodiments, the third surfaces of the plurality of surface microstructures are parallel to each other.

[0008] Optionally, in some embodiments, the height of the surface microstructure protruding from the first surface is less than or equal to 10 μm; or / and the height of the surface microstructure protruding from the first surface is less than or equal to 1 / 3 of the thickness of the substrate.

[0009] Optionally, in some embodiments, when the optical wavelength conversion device is used for excitation, the angle between the laser and the first surface of the substrate is θ, and the angle between the first surface and the third surface is (90-θ) / 2.

[0010] Optionally, in some embodiments, the third surface is a diffuse reflection surface.

[0011] Optionally, in some embodiments, the surface microstructure further includes a fourth surface, the fourth surface is arranged adjacent to the third surface, the side of the fourth surface away from the third surface is connected to the first surface of the substrate, and the side of the third surface away from the fourth surface is connected to the first surface of the substrate; the fourth surface is arranged perpendicular to the first surface of the substrate.

[0012] Optionally, in some embodiments, a light absorbing layer is provided on the fourth surface.

[0013] Optionally, in some embodiments, the third surface and the fourth surface of two adjacent surface microstructures are arranged relative to each other and connected to each other, or the third surface and the fourth surface of two adjacent surface microstructures are arranged relative to each other and spaced from each other, and the first surface of the substrate is connected between the third surface and the fourth surface of the two adjacent surface microstructures.

[0014] In a second aspect, the present application also provides a light source, which includes a light-emitting module and the above-mentioned light wavelength conversion device, the light wavelength conversion device is arranged on the light path of the light-emitting module, and the light-emitting module is used to emit laser light to the light wavelength conversion device.

[0015] In the optical wavelength conversion device provided herein, due to the provision of multiple surface microstructures, when laser light is irradiated onto the third surface of the surface microstructures, the third surface absorbs the laser light to generate fluorescence and reflects the unabsorbed laser light. Since the reflection direction of the unabsorbed laser light is consistent with the specified direction, the reflected laser light and the excited fluorescence light are uniformly mixed and emitted in the specified direction, thereby preventing the reflected laser light from being emitted in other directions and generating stray light, thereby reducing the negative impact of the reflected laser light on the lighting quality. In addition, since the third surface is inclined relative to the first surface of the substrate, the incident angle of the laser light can be reduced, thereby reducing the Fresnel reflection of the laser light on the third surface, while increasing the amount of laser light used to excite fluorescence, improving the utilization rate of the laser light, and generating more fluorescence, thereby increasing the light intensity and improving the lighting quality. Finally, since the optical wavelength conversion device provided with the surface microstructures on the first surface of the substrate can eliminate or reduce the stray light generated by the reflected laser light, without the need for additional filters or other light collection components, the optical wavelength conversion device provided herein also has the advantages of simple structure, compact size, and low cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solution of the present application, the following is a brief introduction to the drawings required for use in the implementation. Obviously, the drawings described below are only some implementation methods of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0017] Figure 1 This is a schematic diagram of the structure of a laser headlight in the prior art for reflecting laser light in the background technology section of this application.

[0018] Figure 2 It is a schematic structural diagram of an optical wavelength conversion device in some embodiments of the present application.

[0019] Figure 3 It is a schematic structural diagram of an optical wavelength conversion device in some other embodiments of the present application.

[0020] Figure 4 It is a schematic structural diagram of an optical wavelength conversion device in some other embodiments of the present application.

[0021] Figure 5 It is a schematic structural diagram of a single surface microstructure in some embodiments of the present application.

[0022] Figure 6 It is a schematic structural diagram of the light source in some embodiments of the present application.

[0023] Explanation of reference numerals: 100, optical wavelength conversion device; 10, substrate; 101, first surface; 102, second surface; 20, surface microstructure; 201, third surface; 202, fourth surface; 30, fluorescent ceramic sheet; 40, incident laser; 50, fluorescence; 60, reflected laser; 200, light source; 21, housing; 22, light-emitting module. DETAILED DESCRIPTION

[0024] In order to enable those skilled in the art to better understand the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0025] In the description of this application, it should be understood that the terms "length," "width," "thickness," "up," "down," "left," "right," "front," "back," "top," "bottom," "inside," "outside," "center," "vertical," "horizontal," "transverse," and "longitudinal" and the like, indicating positions or state relationships, are based on the positions or state relationships shown in the accompanying drawings. These terms are primarily intended to better describe this application and its embodiments, and are not intended to limit the devices, elements, or components indicated to having a specific position, or being constructed or operated in a specific position.

[0026] Furthermore, some of the above terms may be used to express other meanings besides indicating a position or state. For example, the term "on" may also be used to express a dependency or connection in certain circumstances. Those skilled in the art will understand the specific meanings of these terms in this application based on the specific circumstances.

[0027] In addition, the terms "first," "second," etc. are primarily used to distinguish different devices, elements, or components (the specific types and configurations of which may be the same or different), and are not intended to indicate or imply the relative importance or quantity of the devices, elements, or components indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of this application, "plurality" means at least two, such as two, three, etc., unless otherwise specifically defined.

[0028] Furthermore, unless otherwise expressly specified or limited, the terms "mounted," "connected," "connect," and "fixed" should be interpreted broadly. For example, these terms may refer to fixed, removable, or integral connections; mechanical or electrical connections; direct or indirect connections through an intermediary; internal communication between two components; or mere surface contact. Those skilled in the art will understand the specific meanings of these terms in this application based on the specific circumstances.

[0029] If certain terms are used in the specification and claims to refer to specific components, those skilled in the art should understand that hardware manufacturers may use different terms to refer to the same component. The specification and claims do not distinguish components based on differences in name, but rather on differences in their functionality. For example, the term "including" used throughout the specification and claims is an open-ended term and should be interpreted as meaning "including but not limited to." "Substantially" means that those skilled in the art can solve the technical problem within a certain error range and achieve a substantial technical effect.

[0030] See also Figure 2 The embodiments of the present application provide a light wavelength conversion device 100, which is used to receive laser light and emit fluorescence 50 in a specified direction under the excitation of the laser light. The wavelength conversion device 100 is typically used in lighting equipment (such as the light source 200 below) or projection light machines (such as projection displays). The lighting equipment or projection light machine is internally provided with a module for emitting laser light (such as the light-emitting module 22 below). The wavelength conversion device can receive the laser light and excite it to produce fluorescence 50, thereby realizing the lighting function of the lighting equipment or the projection function of the projection light machine.

[0031] The optical wavelength conversion device 100 includes a substrate 10 and a plurality of surface microstructures 20. The substrate 10 is a material plate for receiving laser light and capable of generating fluorescence 50, such as a fluorescent ceramic plate. In the drawings of the present embodiment, the substrate 10 is generally rectangular. In other embodiments, the substrate 10 may also be any shape, such as a circle or a trapezoid. The substrate 10 has a thickness direction Y and includes a first surface 101 and a second surface 102. The first surface 101 and the second surface 102 are located on either side of the substrate 10 in the thickness direction Y. The plurality of surface microstructures 20 are arranged on the first surface 101 of the substrate 10. The surface microstructures 20 have a third surface 201 that is inclined relative to the first surface 101. The third surface 201 is provided with a wavelength conversion layer, so that the third surface 201 is used to absorb laser light (incident laser light 40) to generate fluorescence 50 and reflect unabsorbed laser light (reflected laser light 60), and the reflection direction of the unabsorbed laser light (reflected laser light 60) is consistent with a specified direction. The wavelength conversion layer is a phosphor layer. Its core component is a fluorescent dye, a photosensitive compound that absorbs light energy of a specific wavelength and converts it into light of a longer wavelength. The wavelength conversion layer covers the third surface 201. When incident laser light 40 strikes the third surface 201, the wavelength conversion layer generates and reflects fluorescent light 50 while also reflecting a portion of the laser light (i.e., reflected laser light 60).

[0032] Through the above arrangement, since the surface microstructure 20 is provided, the third surface 201 of the surface microstructure 20 is inclined relative to the first surface 101 of the substrate 10, so the incident angle of the incident laser 40 relative to the first surface 101 of the substrate 10 is reduced, so the Fresnel reflection of the laser on the surface of the light wavelength conversion device can be reduced, which will increase the laser used to excite the fluorescence 50, so that more laser can excite the fluorescence 50; at the same time, the reflected laser 60 and the fluorescence 50 are emitted along the same designated direction, so that the reflected laser 60 is mixed with the excited fluorescence 50 to obtain white light, thereby reducing the interference of the reflected laser 60 on the lighting light, thereby improving the lighting quality; finally, the above-mentioned surface microstructure 20 can also control the reflection direction of the reflected laser 60 to prevent the laser from damaging the internal structure of the lighting device.

[0033] In some embodiments, the third surface 201 is a diffusely reflective surface, for example, a frosted surface can be obtained by frosting the third surface 201. With the above arrangement, when the incident laser light 40 contacts the third surface 201, it can fully contact the third surface 201 to generate fluorescence 50, and the excitation efficiency of the fluorescence 50 is high, thereby ensuring high lighting quality.

[0034] In some embodiments, a plurality of surface microstructures 20 are arranged in an array on the first surface 101 of the substrate 10 and protrude relative to the first surface 101, and the third surfaces 201 of the plurality of surface microstructures 20 are parallel to each other. As a specific example, in the drawings of the specification of this embodiment, the plurality of surface microstructures 20 are arranged in an array along the illustrated direction X. In other embodiments, the plurality of surface microstructures 20 can also be arranged in an array on the first surface 101 along any other direction. Through the above arrangement, the plurality of surface microstructures 20 can synchronously reflect the incident laser light 40 having the same incident direction, and while exciting the fluorescence 50, can ensure that the reflected laser light 60 generated by each beam of incident laser light 40 can be reflected along the same specified direction, thereby ensuring that the reflected laser light 60 is fully mixed with the fluorescence 50 to improve the lighting quality.

[0035] In some embodiments, the height h1 of the surface microstructure 20 relative to the first surface 101 (see Figure 2 、 Figure 3 and Figure 4 ) is less than or equal to 10 μm. For example, the height h1 of the surface microstructure 20 protruding relative to the first surface 101 can be 1 μm, 2 μm, 3 μm, 4 μm, 5 μm, 6 μm, 7 μm, 8 μm, 9 μm, 10 μm, or any other value. In some embodiments, the height h1 of the surface microstructure 20 protruding relative to the first surface 101 is less than or equal to 1 / 3 of the thickness h2 of the substrate 10. Through the above arrangement, it is possible to avoid the negative impact of the surface microstructure 20 on the excitation of the fluorescence 50 due to its own excessive thickness. Moreover, the smaller the height h1 of the surface microstructure 20 protruding relative to the first surface 101, the smaller its structure, and the smaller the negative impact on the fluorescence 50.

[0036] See also Figure 5 In some embodiments, when the optical wavelength conversion device 100 is used for excitation, the angle between the incident laser 40 and the first surface 101 of the substrate 10 is θ, and the angle between the first surface 101 and the third surface 201 is (90-θ) / 2 ( Figure 5Since the angle between the first surface 101 and the third surface 201 is (90-θ) / 2, the incident angle of the incident laser light 40 on the third surface 201 (the angle between the incident laser light 40 and the normal O) plus θ (the angle between the incident laser light 40 and the first surface 101) plus (90-θ) / 2 (the angle between the first surface 101 and the third surface 201) equals 90°. The angle between the reflected laser light 50 and the first surface 101 is equal to the incident angle of the incident laser light 40 on the third surface 201 plus θ (the angle between the incident laser light 40 and the first surface 101) plus the reflection angle of the reflected laser light 50 on the third surface 201 (the angle between the reflected laser light 50 and the normal O). When the angle between the first surface 101 and the third surface 201 is (90-θ) / 2, the incident angle of the incident laser light 40 on the third surface 201 (equal to the reflection angle of the reflected laser light 50 on the third surface 201) is also (90-θ) / 2 (90 minus θ minus (90-θ) / 2). At this time, the angle between the reflected laser light 60 and the first surface 101 is 90° (θ plus (90-θ) / 2 plus (90-θ) / 2). Therefore, by setting the above angle, it is possible to ensure that the reflected laser 60 is emitted along the thickness direction Y of the substrate 10, thereby ensuring that the emission direction of the reflected laser 60 is the same as the reflection direction of the fluorescence 50, so as to ensure that the reflected laser 60 and the fluorescence 50 are fully mixed and uniform.

[0037] See also Figure 2 In some embodiments, two adjacent surface microstructures 20 are continuously connected. Figure 3 In some other embodiments, two adjacent surface microstructures 20 are spaced apart. Figure 2 In the embodiment shown, the third surface 201 and the fourth surface 202 of two adjacent surface microstructures 20 are arranged opposite to each other and connected to each other. Figure 3 In the embodiment shown, the third surface 201 and the fourth surface 202 of two adjacent surface microstructures 20 are arranged opposite to each other and are spaced apart from each other. The first surface 101 of the substrate 10 is connected between the third surface 201 and the fourth surface 202 of the two adjacent surface microstructures 20. Figure 4 The embodiment shown, Figure 3 In the embodiment shown, the arrangement of the plurality of surface microstructures 20 on the first surface 101 is more dense. When the number of surface microstructures 20 to be arranged is determined, Figure 3 The embodiment shown is Figure 4 The embodiment shown can occupy a smaller space, thereby reducing the area of ​​the substrate 10, thereby saving material costs and space. When the size of the substrate 10 is determined, Figure 3 The embodiment shown is Figure 4The illustrated embodiment may provide a greater number of surface microstructures 20 on the substrate 10 , thereby improving the reflection effect and efficiency of the incident laser light 40 , and ensuring that the reflected laser light 60 and the fluorescent light 50 are fully and evenly mixed.

[0038] See also Figure 2 or Figure 3 In some embodiments, the surface microstructure 20 further includes a fourth surface 202, which is disposed adjacent to the third surface 201 and located on the side of the third surface 201 facing away from the incident laser light 40. The side of the fourth surface 202 facing away from the third surface 201 is connected to the first surface 101 of the substrate 10, and the side of the third surface 201 facing away from the fourth surface 202 is connected to the first surface 101 of the substrate 10. The fourth surface 202 is disposed perpendicular to the first surface 101 of the substrate 10. Due to the above arrangement, since the fourth surface 202 is disposed perpendicular to the first surface 101 of the substrate 10, the width of a single surface microstructure 20 in the illustrated direction X can be reduced, thereby reducing the space occupied by a single surface microstructure 20 on the substrate 10, thereby facilitating the provision of a larger number of surface microstructures 20 on the substrate 10. It should be noted that when the fourth surface 202 is substantially perpendicular to the first surface 101, it does not participate in the excitation or reflection of the incident laser light 40. Therefore, the generation of stray laser light can be avoided, and the third surface 201 can be fully utilized, resulting in relatively high efficiency in excitation of the fluorescent light 50. In some other embodiments, for example Figure 4 In the embodiment shown, the fourth surface 202 may not be perpendicular to the first surface 101 of the substrate 10 , which is not limited thereto.

[0039] In some embodiments, a light-absorbing layer is provided on the fourth surface 202. For example, the light-absorbing layer can be a black coating, ink coating, or other light-absorbing coating. As a specific example, the surface microstructure 20 can be a black grid structure. The reflective surface (white surface) of the black grid structure is the third surface 201 of the surface microstructure 20, and the light-absorbing surface (black surface) of the black grid structure is the light-absorbing layer on the fourth surface 202 of the surface microstructure 20. Through this arrangement, the black grid structure can not only reflect laser light so that the reflected laser light 60 coincides with the direction of the fluorescent light 50, but also absorb stray light from other directions through the fourth surface 202, thereby reducing the negative impact of stray light on laser reflection.

[0040] See also Figure 6Based on the aforementioned optical wavelength conversion device 100, this embodiment further provides a light source 200, which can be any light-emitting device, such as a laser headlight used in an automobile. The light source 200 includes a housing 21, a light-emitting module 22, and the aforementioned optical wavelength conversion device 100. Both the light-emitting module 22 and the optical wavelength conversion device 100 are disposed within the housing 21. The light-emitting module 22 is configured to emit laser light toward the optical wavelength conversion device 100, and the optical wavelength conversion device 100 is disposed in the optical path of the laser light emitted by the light-emitting module 22. Through the above arrangement, the laser emitted by the light source 200 module is irradiated onto the optical wavelength conversion device 100. The optical wavelength conversion device 100 can make the reflected laser 60 and the fluorescent light 50 have the same reflection direction, so that the reflected laser 60 and the fluorescent light 50 are evenly mixed to reduce the negative impact of the reflected laser 60 on the lighting effect; and the surface microstructure 20 can also reduce the incident angle of the incident laser 40, thereby reducing the Fresnel reflection of the laser on the surface of the optical wavelength conversion device 100, thereby increasing the laser that excites the fluorescent light 50 to improve the lighting quality; in addition, because the surface microstructure 20 can adjust the reflection direction of the reflected laser 60, it can prevent the reflected laser 60 from irradiating other structures inside the light source 200 to cause damage to other structures, thereby also improving the safety and stability of the light source 200.

[0041] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and features of different embodiments or examples without contradiction.

[0042] Finally, it should be noted that the above embodiments are intended only to illustrate the technical solutions of this application and are not intended to limit them. Although this application has been described in detail with reference to the aforementioned embodiments, those skilled in the art will appreciate that they may modify the technical solutions described in the aforementioned embodiments or substitute equivalent features for some of the technical features. However, such modifications or substitutions do not deviate from the spirit and scope of the technical solutions of the various embodiments of this application.

Claims

1. An optical wavelength conversion device, characterized in that: The optical wavelength conversion device is used to receive laser light and emit fluorescence in a specified direction under the excitation of the laser light, and the optical wavelength conversion device includes: A substrate, wherein the substrate has a thickness direction, the substrate comprises a first surface and a second surface, the first surface and the second surface are located on both sides of the substrate in the thickness direction; A plurality of surface microstructures are arranged on the first surface of the substrate, wherein the surface microstructures have a third surface, wherein the third surface is inclined relative to the first surface, and wherein a wavelength conversion layer is provided on the third surface so that the third surface is used to absorb the laser to generate the fluorescence and reflect the laser that is not absorbed, and the reflection direction of the laser that is not absorbed is consistent with the specified direction.

2. The optical wavelength conversion device according to claim 1, wherein: A plurality of surface microstructure arrays are arranged on the first surface of the substrate and protrude relative to the first surface.

3. The optical wavelength conversion device according to claim 2, characterized in that: The third surfaces of the plurality of surface microstructures are parallel to each other.

4. The optical wavelength conversion device according to claim 2, wherein: The height of the surface microstructure protruding relative to the first surface is less than or equal to 10 μm; or / and, A height of the surface microstructure protruding relative to the first surface is less than or equal to 1 / 3 of the thickness of the substrate.

5. The optical wavelength conversion device according to claim 1, wherein: When the optical wavelength conversion device is used for excitation, the angle between the laser and the first surface of the substrate is θ, and the angle between the first surface and the third surface is (90-θ) / 2.

6. The optical wavelength conversion device according to claim 1, wherein: The third surface is a diffuse reflection surface.

7. The optical wavelength conversion device according to any one of claims 1 to 6, characterized in that: The surface microstructure also includes a fourth surface, which is arranged adjacent to the third surface, and the side of the fourth surface away from the third surface is connected to the first surface of the substrate, and the side of the third surface away from the fourth surface is connected to the first surface of the substrate; the fourth surface is arranged perpendicular to the first surface of the substrate.

8. The optical wavelength conversion device according to claim 7, characterized in that: A light absorbing layer is disposed on the fourth surface.

9. The optical wavelength conversion device according to claim 7, wherein: The third surface and the fourth surface of two adjacent surface microstructures are arranged opposite to each other and connected to each other; or, The third surface and the fourth surface of two adjacent surface microstructures are arranged opposite to each other and are spaced apart from each other, and the first surface of the substrate is connected between the third surface and the fourth surface of two adjacent surface microstructures.

10. A light source, characterized in that: include: A light emitting module and an optical wavelength conversion device as claimed in any one of claims 1 to 9, wherein the optical wavelength conversion device is arranged on the optical path of the light emitting module, and the light emitting module is used to emit laser light to the optical wavelength conversion device.

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