A lighting device

Abstract

The present invention provides a lighting device, comprising: a light source and a first light guide, wherein the first light guide comprises a first light guide portion and a second light guide portion, the second light guide portion comprises a light emitting surface, the light emitted by the light source is coupled into the first light guide portion and emitted from the light emitting surface of the second light guide portion; the cross-sectional area of ​​the second light guide portion perpendicular to the center line of the first light guide gradually decreases along the optical axis direction of the light source; the light emitting surface does not have rotational symmetry. Through the above arrangement, the light emitted from the light emitting surface is unevenly distributed in space, and by changing the light distribution of the light emitted by the lighting device, it is beneficial to reduce light loss and improve light utilization.

Description

Technical Field

[0001] The invention relates to the field of automobile lighting, and in particular to a lighting device for automobile lamps. Background Art

[0002] LED light sources have advantages such as energy saving, environmental protection and long life, but the existing LED light sources are one-sided luminous bodies, and their luminous characteristics are different from those of traditional car lamp filaments such as halogen filaments or tungsten filaments, making them unable to directly replace traditional filaments. The prior art proposes a virtual filament, which guides the light emitted by the LED light source into a light guide rod to simulate the luminous characteristics of traditional filaments, so that it can directly replace traditional filaments.

[0003] The existing virtual filaments have symmetrical light-emitting parts, and the emitted illumination light is evenly distributed in 360 degrees. When applied to a reflective bowl, a predetermined light distribution pattern can be obtained, wherein the light-emitting part of the virtual filament is set at the focus of the reflective bowl, and the light emitted at different angles is reflected by different areas of the reflective bowl to form different areas of the illumination light pattern. Figure 1 As shown, the light emitted upward from the light emitting part of the virtual filament is reflected by the reflective area above the reflective bowl and then illuminates the area above the hh line of the illumination light pattern, while the light emitted downward from the light emitting part is reflected by the reflective area below the reflective bowl and then illuminates the area below the hh line of the illumination light pattern.

[0004] The main reason for limiting the application of virtual filaments is that the illumination light pattern formed by the virtual filaments cannot meet the requirements of automotive filament bulb headlights, such as the low illumination in zone II that does not meet the requirements. In the prior art, in order to increase the brightness of the light emitted by the virtual filament, the diameter of the light guide rod can be increased, and then the number of light sources on the light-entering surface of the light guide rod can be increased, thereby increasing the luminous flux coupled through the light guide rod, and ultimately increasing the brightness of the light emitted by the light-emitting portion; but increasing the diameter of the light guide rod will also increase the degree of defocusing of the light-emitting portion at the focus of the reflective bowl, so that the light emitted upward from the light-emitting portion is reflected by the reflective area above the reflective bowl and tilted downward to illuminate the area below the hh line, while the light emitted downward from the light-emitting portion is reflected by the reflective area below the reflective bowl and tilted upward to illuminate the area above the hh line, and the illumination of zone III of the low beam pattern obtained does not meet the requirements of automotive filament bulb headlights.

[0005] In the prior art, by setting a light baffle, the illumination light emitted by the virtual filament can be formed as follows: Figure 1 The low beam lighting pattern shown in the figure, however, using a light baffle to form the low beam pattern will result in greater light loss and lower light utilization efficiency. Summary of the invention

[0006] In view of the defects existing in the formation of low beam patterns in the above-mentioned prior art, the present invention provides a lighting device, comprising: a light source and a first light guide, wherein the first light guide comprises a first light guide portion and a second light guide portion, the second light guide portion comprises a light-emitting surface, light emitted by the light source is coupled into the first light guide portion and emitted from the light-emitting surface of the second light guide portion; the cross-sectional area of ​​the second light guide portion perpendicular to the center line of the first light guide gradually decreases along the direction of the optical axis of the light source; and the light-emitting surface does not have rotational symmetry.

[0007] Through the above settings, the spatial light distribution of the emitted light is optimized by utilizing the light-emitting surface, so that the light emitted from the light-emitting surface is unevenly distributed in space. By changing the light distribution of the emitted light of the lighting device, it is beneficial to reduce light loss and improve light utilization.

[0008] In one embodiment, the light emitting surface is a portion of a side surface of a right cone or a right truncated cone.

[0009] In one embodiment, the axis of the right cone or the right frustum of a cone is parallel to and does not overlap with the center line of the first light guiding portion.

[0010] In one embodiment, the second light guiding portion further includes a first reflective surface, and a combined surface of the light emitting surface and the first reflective surface has rotational symmetry.

[0011] In one embodiment, the light emitting surface is a side surface of an oblique cone or an oblique frustum of a pyramid.

[0012] In one embodiment, the light emitting surface is at least a portion of a side surface of a wedge-shaped body.

[0013] In one embodiment, the second light guide portion includes a first bottom surface and a second bottom surface that are oppositely disposed, the second bottom surface is disposed at an end of the second light guide portion, and a second reflective layer is disposed on the second bottom surface.

[0014] In one embodiment, the first light guide portion is a column structure or a frustum structure; the first light guide portion and the second light guide portion are integrally formed.

[0015] In one embodiment, a cross section of the first light guide portion perpendicular to the center line of the first light guide is a square structure including two rounded corners, and an orthographic projection of a vertex of the second light guide portion within the cross section is located on a side away from the rounded corners.

[0016] In one embodiment, the second light guiding portion includes a third reflecting surface, and the third reflecting surface and at least a portion of the side surface of the first light guiding portion are continuous surfaces.

[0017] In one embodiment, the light emitting surface is provided with a scattering structure and / or a fluorescent layer for scattering the light emitted by the light source or converting its wavelength.

[0018] In one embodiment, the first light guide further includes: a heat dissipation layer, which is arranged on at least a portion of the side surface of the first light guide portion and is used to dissipate heat from the first light guide; a transparent adhesive layer, which is used to adhere the heat dissipation layer to the side surface of the first light guide portion so that the heat of the first light guide is conducted to the heat dissipation layer, wherein the refractive index of the transparent adhesive layer is lower than the refractive index of the first light guide.

[0019] In one embodiment, the lighting device further comprises an optical lens, which is disposed on a light path between the light source and the first light conductor so that an incident angle of light emitted by the light source on the first light conductor is smaller than a preset value.

[0020] In one embodiment, the lighting device further includes a second light guide, which is the same as the first light guide, and includes a first light guide portion and a second light guide portion, and the light emitted by the light source is at least partially coupled into the third light guide portion and emitted from the light emitting surface of the fourth light guide portion, and the end of the first light guide is relatively close to the end of the second light guide. Through the above arrangement, the brightness of the light emitted by the lighting device is doubled.

[0021] In one embodiment, the lighting device further comprises a reflective bowl, the second light guide portion is arranged at the focal position of the reflective bowl, and the reflective bowl is used to reflect the light emitted from the light emitting surface to the outside. Through the above arrangement, the lighting device obtains the desired low beam pattern. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 The light distribution pattern of existing automobile headlights;

[0023] Figure 2 This is a schematic structural diagram of a lighting device according to a first embodiment of the present application;

[0024] Figure 3 This is a schematic structural diagram of the first light guide in the first embodiment of the present application;

[0025] Figure 4 This is a schematic structural diagram of the first light guide in a variant embodiment of the first embodiment of the present application;

[0026] Figure 5 This is a schematic structural diagram of a first light guide in yet another variant embodiment of the first embodiment of the present application;

[0027] Figure 6This is a schematic structural diagram of a first light guide in yet another variant embodiment of the first embodiment of the present application;

[0028] Figure 7 It is a schematic structural diagram of an illumination device and a first light guide according to a second embodiment of the present application;

[0029] Figure 8 A schematic structural diagram of an illumination device and a first light guide according to a third embodiment of the present application;

[0030] Fig. 9 A schematic structural diagram of a lighting device according to a fourth embodiment of the present application;

[0031] Fig.10 This is a schematic structural diagram of the first light guide in the fourth embodiment of the present application;

[0032] Fig.11 A schematic structural diagram of an illumination device and a first light guide according to a fifth embodiment of the present application;

[0033] Fig.12 This is a schematic structural diagram of a lighting device according to a sixth embodiment of the present application;

[0034] Fig.13 This is a schematic structural diagram of a lighting device according to a seventh embodiment of the present application;

[0035] Fig.14 It is a schematic structural diagram of a lighting device according to the eighth embodiment of the present application. DETAILED DESCRIPTION

[0036] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0037] It should be noted that if the embodiments of the present application involve directional indications (such as up, down, left, right, front, back...), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0038] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present application, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or suggesting their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in the field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by this application.

[0039] The “rotational symmetry” mentioned in the present invention means that the target object can coincide with itself after rotating around an axis by an angle a, and 0°<a<360°.

[0040] See also Figure 2 , Figure 2 1 is a schematic diagram of the structure of the first embodiment of the lighting device of the present application. The lighting device 100 of this embodiment includes: a light source 110 and a first light guide 120, the first light guide 120 includes a first light guide portion 121 and a second light guide portion 122, the second light guide portion 122 includes a light emitting surface 123, wherein the light emitted by the light source 100 enters the first light guide portion 121, and after being transmitted, is emitted from the light emitting surface 123 of the second light guide portion 122. In this embodiment, the cross-sectional area of ​​the second light guide portion 122 perpendicular to the central axis of the first light guide 120 gradually decreases along the direction of the light source optical axis, and the light emitting surface 123 does not have rotational symmetry.

[0041] The light emitted by the light source 110 enters the first light guide 120 through a bottom surface of the first light guide 121, undergoes TIR conduction in the first light guide 121, and enters the second light guide 122 from the other bottom surface of the first light guide 121. Some light rays are directly emitted from the light emitting surface 123 of the second light guide 122, such as light rays S1, S2, and S3, and a small portion of light rays are first totally internally reflected on the cylindrical surface of the second light guide 122, and then emitted from the light emitting surface 123, such as S4. Through the above arrangement, the light emitted from the light emitting surface 123 is unevenly distributed in space. By changing the light distribution of the light emitted from the light emitting surface 123, it is beneficial to reduce light loss and improve light utilization.

[0042] In this embodiment, the light source 110 may be an LED light source, a laser light source or other solid-state light source, and the light source 110 is composed of at least one of the above light sources. For example, in a specific embodiment of the present invention, the light source 110 includes 4 LED chips.

[0043] The first light guide 120 may be made of a material with good light transmittance, such as PMMA, quartz, glass, sapphire, YAG single crystal, etc. In this embodiment, light propagates in the first light guide 120 in a total reflection manner, which can have a very high reflectivity and reduce the complexity of the process caused by the coating of a reflective film, etc. It can be understood that in some other embodiments of the present invention, a first light guide with a reflective film disposed on a portion of the surface can also be used to achieve light conduction. The main difference lies in the preparation process, which will not be repeated here.

[0044] The light emitting surface 123 is provided with a scattering structure, and the scattering structure can be obtained by, for example, roughening the conical surface of the second light guide portion 122; or microstructuring the conical surface of the second light guide portion 122; or coating the conical surface of the second light guide portion 122 with a scattering layer.

[0045] In some embodiments of the present invention, the scattering layer includes scattering particles and a carrier, and the refractive index of the carrier is greater than the refractive index of the first light conductor, so that it becomes a scattering surface, and light can be emitted from the light-emitting surface 123. Specifically, the scattering layer can be a mixture of titanium oxide powder and glue or glass, and the refractive index of the glue or glass is greater than the refractive index of the second light guide part, so as to form the light-emitting surface 123, and the light can be scattered outward, thereby forming illumination light.

[0046] In a specific embodiment, the light-emitting surface 123 may be formed by setting a fluorescent layer on the conical surface of the second light-guiding portion 122. The fluorescent layer may be formed by mixing fluorescent powder and its carrier. The carrier may be, for example, glue, glass, etc. The fluorescent powder may be, for example, yellow fluorescent powder, green fluorescent powder, red fluorescent powder, or a mixture of several fluorescent powders, etc. In a specific embodiment, the wavelength of light emitted by the light source is converted by exciting the fluorescent powder to form illumination light.

[0047] In the present invention, the first light guide includes a first light guide portion and a second light guide portion. In some embodiments, the first light guide portion and the second light guide portion can be defined as follows: the first light guide is divided into two parts by a plane that is perpendicular to the optical axis of the light source (or the center line of the first light guide portion) and tangent to the light-emitting surface, so that the portion of the two parts close to the light source does not contain the light-emitting surface and is the first light guide portion, and the portion away from the light source is the second light guide portion that includes the light-emitting surface.

[0048] The first light guide portion 121 and the second light guide portion 122 of the first light guide 120 may be integrally formed, or may be separately formed and then glued together. When the first light guide portion 121 and the second light guide portion 122 are integrally formed, the second light guide portion 122 further includes a third reflection surface (not shown in the figure), and the third reflection surface is a continuous surface with at least part of the side surface of the first light guide portion. In fact, the third reflection surface is an extension surface of the total reflection surface of the first light guide portion 121. In the present invention, for the technical solution in which the first light guide portion and the second light guide portion are integrally formed, the first light guide can be obtained by processing on the basis of an original light guide, for example, grinding one end of a cylindrical light guide into a cone / truncated cone shape, that is, a first light guide consisting of the first light guide portion and the second light guide portion is obtained.

[0049] Specifically, Figure 3 As shown in (a) and (b), Figure 3 (a) is a three-dimensional diagram of the first light guide 120, Figure 3 (b) is a right view of the first light guide 120; the first light guide 120 includes a first light guide portion 121 and a second light guide portion 122. The first light guide portion 121 is a cylindrical structure including two bottom surfaces and a cylindrical surface; the second light guide portion 122 is a structure including a bottom surface, a portion of a conical surface and a portion of a cylindrical surface, and the conical surface portion is divided into a light-emitting surface 123, which is a portion of the side surface of a right cone (not a complete conical surface). Among them, the bottom surface of the first light guide portion 121 and the bottom surface of the second light guide portion 122 are equal in area, which is used to realize the connection between the first light guide portion 121 and the second light guide portion 122 (in the technical solution in which the first light guide portion and the second light guide portion are integrally formed, the bottom surface is a virtual surface), corresponding to Figure 2 The dotted line position in . In the present embodiment, the first light guide portion 121 is a cylinder of the minimum length that passes through the intersection of the cylinder and the cone and is perpendicular to the center line L2 of the first light guide portion 121. The second light guide portion 122 is the portion of the light guide 120 other than the first light guide portion 121. The straight line that passes through the vertex or the midpoint of the end of the second light guide portion 122 and is perpendicular to the bottom surface of the second light guide portion 122 is L1. In the present embodiment, the light emitting surface 123 is a part of the conical surface, and L1 is the axis of the right cone corresponding to the conical surface. After the light emitting surface 123 rotates around the straight line L1 by any angle a (0°<a<360°), it does not coincide with itself. The straight line L1 is parallel to the straight line L2 and does not coincide with it.

[0050] In a variant embodiment of the first embodiment of the present invention, please refer to Figures 4 to 6 The first light guide 120 may also be in other shapes. The following mainly discusses the deformation structure of the first light guide. The description of other technical features of the lighting device can refer to the above description.

[0051] like Figure 4As shown in (a) and (b), the first light guide 120 includes a first light guide portion 121 and a second light guide portion 122, wherein the first light guide portion 121 includes a cylindrical structure including two bottom surfaces, a cylindrical surface and a side plane, and the two bottom surfaces are in a "D" shape, which is formed by cutting off a small part of a full circle with a straight line that does not pass through the center of the circle. The second light guide portion 122 is a structure including a bottom surface, a part of a conical surface and a side plane, and its conical surface portion is divided into a light emitting surface 123, which is also a part of the conical surface of a right circular cone (not a complete conical surface), and the bottom surface of the second light guide portion 122 is the same shape and size as the bottom surface of the first light guide portion 121, and is used to achieve the connection between the first light guide portion 121 and the second light guide portion 122. Specifically, the light guide 120 can be obtained by cutting off a portion of a raw material light guide that is rotationally symmetrical about the center line formed by a cylinder and a cone in one piece by a plane that is parallel to the center line of the light guide and does not pass through the center line, or by polishing the side of the raw material light guide that is rotationally symmetrical about the center line formed by a cylinder and a cone in one piece. In this case, the second light guide portion further includes a third reflection surface (not shown in the figure), and the third reflection surface is a continuous surface with at least part of the side surface of the first light guide portion 121, and the third reflection surface is the above-mentioned side plane.

[0052] like Figure 5 As shown in (a) and (b), the first light guide portion 121 of the first light guide 120 is a quadrangular prism including two bottom surfaces and four side planes, and the two bottom surfaces are square. The second light guide portion 122 is a structure including a bottom surface, a portion of a conical surface and four side planes, and the conical surface portion is divided into a light-emitting surface 123, and the conical surface portion is also a portion of the conical surface of a right circular cone (not a complete conical surface).

[0053] like Figure 6 As shown, Figure 6 (a) is a front view of the first light guide 120, (b), (c), (d), (e) are right views of the first light guide 120, and (b), (c), (d), (e) show three other structures of the first light guide 120. Since the cross-sectional area of ​​the second light guide portion perpendicular to the center line of the first light guide gradually decreases along the optical axis of the light source, the right views (b), (c), (d), (e) can actually be regarded as right views of the first light guide portion. Figure 6 In the embodiment shown, the first light guide portion 121 is a columnar structure. Figure 6 (b), (c), (d), and (e) also represent the cross-section of the columnar structure of the first light guide portion 121. For example, Figure 6The first light guide portion 121 of the first light guide 120 shown in (b) is a columnar structure including two bottom surfaces, four side planes and two curved surfaces, and the curved surface is arranged on the side away from the straight line L1, that is, the cross section of the first light guide portion 121 perpendicular to the center line of the first light guide 120 is a square structure including two rounded corners, and the orthographic projection of the vertex of the second light guide portion 122 on the cross section is located on the side away from the two rounded corners, with the center line of the first light guide portion 121 as the center, and the two rounded corners and the orthographic projection of the vertex are respectively located on both sides of the center line. This structure enables the lighting device to have higher light utilization efficiency and higher central illumination of the lighting spot formed when it is applied to a reflective bowl or other secondary optical elements. It can be understood that when the end of the second light guide portion is a line or a plane, rather than a point, the vertex of the second light guide portion can be considered as the midpoint of the end of the second light guide portion.

[0054] It can be understood that the structure of the first light guide part in the present invention is not limited here, and can be a columnar structure, such as the cylinders, prisms and their mixtures listed above, or a frustum structure, such as a truncated cone structure or a prism structure.

[0055] In the first embodiment of the present invention and its variant embodiments, various structures of the first light guide parts are listed. The function of the first light guide parts is to homogenize the light from the light source so that the light entering the second light guide part is a uniform light field. In the above-mentioned embodiments, the common point of each second light guide part is that its structure includes a part of a right circular cone, and the side of the "incomplete right circular cone" is just the light-emitting surface of the second light guide part, that is, the light-emitting surface is an "incomplete right circular cone surface". Through the above settings, the light-emitting surface 123 can be made asymmetrically rotated around the straight line L1, so that the light emitted by the light-emitting surface 123 is unevenly distributed in space.

[0056] It can be understood that in some other embodiments, the above-mentioned "perfect circular cone" can be replaced by "perfect pyramid", and the cone can be regarded as a case where the number of edges of the pyramid is infinite. In this case, the light-emitting surface is a part of the side of the right pyramid, which is an "incomplete right pyramid surface". In general, the light-emitting surface can be a part of the side of a right cone, and the right cone includes a right circular cone and a right pyramid, and also includes other right cone structures (the orthographic projection of the cone vertex on the cone bottom coincides with the center of the cone bottom).

[0057] The first light guide portion 121 of the first light guide 120 of this embodiment further includes a transparent adhesive layer and a heat dissipation layer. The heat dissipation layer is disposed on at least a portion of the outer surface of the first light guide portion, and is used to dissipate heat from the first light guide 120; the transparent adhesive layer is used to bond the first light guide portion and the heat dissipation layer, so that the heat of the first light guide portion is transferred to the heat dissipation layer, wherein the refractive index of the transparent adhesive layer is lower than the refractive index of the first light guide portion, so that the light emitted by the light source can be totally reflected at the interface between the first light guide portion and the transparent adhesive layer, thereby reducing light loss.

[0058] See also Figure 7 (a), (b) and (c), Figure 7 (a) is a schematic structural diagram of the second embodiment of the lighting device of the present application, Figure 7 (b) is a schematic diagram of the structure of the first light guide of the lighting device according to the second embodiment of the present application, Figure 7 (c) is another schematic diagram of the structure of the first light guide of the lighting device of the second embodiment of the present application. The lighting device 200 includes: a light source 210, a first light guide 220, wherein the light source 210 can refer to the description in the above embodiments and will not be described again here. The difference between the lighting device 200 of this embodiment and the lighting device 100 in the above embodiments mainly lies in the difference in the second light guide portion of the first light guide: the second light guide portion 222 of the first light guide 220 of this embodiment is a part of a truncated cone, which can be regarded as a structure obtained by cutting off the tip of the corresponding cone (i.e., the part near the vertex) on the basis of the above embodiments. The specific structure of the second light guide portion 222 is mainly described below. The first light guide portion 221 of the first light guide 220 in this embodiment can refer to the technical solution of the first light guide portion 121 of the first light guide 120 in the above embodiments.

[0059] like Figure 7 As shown in (b), the second light guide portion 222 of the first light guide 220 is a part of a truncated cone structure, including two bottom surfaces, a conical surface and a cylindrical surface, and the conical surface is divided into a light emitting surface 223; Figure 7 As shown in (c), the second light guide portion 222 of the first light guide 220 is a truncated cone structure including two bottom surfaces, a conical surface and a side plane, and the conical surface is the light emitting surface 223.

[0060] The two bottom surfaces of the second light guide portion 222 are arranged opposite to each other, wherein the first bottom surface has a larger area and is connected to the first light guide portion 221, and the second bottom surface has a smaller area and is arranged at the end of the second light guide portion 222. The second bottom surface is provided with a second reflective layer 224, which can reflect the excitation light emitted from the second end face of the second light guide portion 222 back to the light guide to improve the light efficiency.

[0061] The second reflection layer 224 can be configured as a diffuse reflection layer or a Gaussian scattering reflection layer, wherein diffuse reflection means that the light beam is Lambertian distributed after being reflected by the reflection layer, and the intensity of the reflected light is cosine distributed, and the diffuse reflection material can be a mixture of particles such as TiO2, MgO, BaSO4, etc. and glue or glass powder; Gaussian scattering reflection means that the light beam is Gaussian distributed after being reflected by the reflection layer, and the intensity of the reflected light is Gaussian distributed. The second reflection layer 224 can reflect the light transmitted thereto so that it is emitted from the light emitting surface 223.

[0062] In some other embodiments, the above-mentioned "perfect circular truncated cone" can be replaced with "perfect truncated pyramid", and the circular truncated pyramid is regarded as a case where the number of edges of the truncated pyramid is infinite. In this case, the light-emitting surface is a part of the side of the right truncated pyramid, which is an "incomplete right truncated pyramid surface". In general, the light-emitting surface can be a part of the side of a right truncated pyramid, and the right truncated pyramid includes a right circular truncated pyramid and a right truncated pyramid, and also includes other right truncated pyramid structures.

[0063] It can be understood that in the present invention, the technical solution of providing a second bottom surface with a second reflective layer at the end of the second light guide portion is not limited to the technical solution of the second light guide portion being a part of a frustum. In other embodiments of the present invention, the second bottom surface can also be inclined rather than perpendicular to the optical axis direction of the light source, and the second bottom surface can also be obtained by obliquely cutting off the tip of the corresponding cone on the basis of the first embodiment and its variant embodiments. The shape of the second bottom surface is not limited to a plane structure, and can also be a curved surface structure.

[0064] See also Figure 8 (a), (b) and (c), Figure 8 (a) is a schematic structural diagram of the third embodiment of the lighting device of the present application, Figure 8 (b) is a schematic structural diagram of a first light guide of an illumination device according to a third embodiment of the present application, Figure 8 (c) is a right view of the first light guide. The lighting device 300 of this embodiment includes: a light source 310 and a first light guide 320, wherein the light source 310 is consistent with that described in the above embodiment and will not be described again. The first light guide 320 includes a first light guide portion 321 and a second light guide portion 322, wherein the cross-sectional area of ​​the second light guide portion 322 perpendicular to the central axis of the first light guide 320 gradually decreases along the direction of the light axis of the light source, and the second light guide portion is rotationally symmetrical around the central axis L; the second light guide portion 322 includes a light emitting surface 323 and a first reflective surface 324, and the combined surface of the light emitting surface 323 and the first reflective surface 324 is rotationally symmetrical.

[0065] Specifically, Figure 8As shown in (b) and (c), the first light guide 320 includes a first light guide portion 321 and a second light guide portion 322, wherein the first light guide portion 321 is a cylindrical structure including two bottom surfaces and a cylindrical surface, and the second light guide portion 322 is a right circular cone structure including a bottom surface and a conical surface, and a light emitting surface 323 and a light absorbing surface 324 are arranged on the conical surface of the second light guide portion 322, and the bottom surface of the first light guide portion 321 and the bottom surface of the second light guide portion 322 are of the same size, so as to realize the connection between the first light guide portion 321 and the second light guide portion 322. By setting a part of the conical surface of the second light guide portion 322 as the first reflecting surface 324, the light emitting surface 323 is rotationally asymmetric around the center line of the light guide, thereby making the light emitted from the light emitting surface 323 unevenly distributed in space, and further, the light is guided to the light emitting surface opposite to it by using the first reflecting surface 324, thereby further changing the spatial distribution of the emitted light. Compared with the above-mentioned embodiments, since the first light guide portion 321 and the second light guide portion 322 of the first light guide 320 of this embodiment are rotationally symmetrical structures, the processing of the light guide is simpler.

[0066] In addition, the first light guide portion 321 of the first light guide 320 may also be other structures, such as a truncated cone, a truncated cone structure or a prism structure, etc.; the second light guide portion 322 may also be a truncated cone structure, a pyramid structure, a truncated cone structure, etc. In an actual application scenario, in order to simplify the preparation process of the first light guide 320, the second light guide portion may not be provided with the first reflective surface 324, and the second bottom surface of the second light guide portion 321 of the truncated cone structure may be set to be inclined relative to the optical axis direction of the light source rather than perpendicular, and the conical surface is the light-emitting surface. At this time, the light-emitting surface does not have rotational symmetry. Through the above setting, the light emitted from the light-emitting surface is unevenly distributed in space.

[0067] In this embodiment, the light emitted by the light source 310 is coupled from the first light guide portion 321 into the first light guide 320, and is emitted from the light emitting surface 323 of the second light guide portion 322 or is reflected by the first reflection surface 324 of the second light guide portion 322, wherein most of the light will be emitted from the light emitting surface 323, and a small part of the light will be transmitted to the first reflection surface 324, where it is reflected and then emitted from the light emitting surface 323 to the outside.

[0068] See also Fig. 9 , Fig. 9 4 is a schematic diagram of the structure of the fourth embodiment of the lighting device of the present application. The lighting device 400 of this embodiment includes: a light source 410 and a first light guide 420, wherein the light source 410 is consistent with that described in the above embodiment and is not described again. The first light guide 420 includes a first light guide portion 421 and a second light guide portion 422, wherein the cross-sectional area of ​​the second light guide portion 422 perpendicular to the central axis of the first light guide 420 gradually decreases along the direction of the light source optical axis, and the second light guide portion 422 includes a light emitting surface 423, and the light emitting surface 423 does not have rotational symmetry.

[0069] In this embodiment, if Fig.10 As shown in (a), (b) and (c), Fig.10 (a) is a three-dimensional diagram of the first light guide 420, Fig.10 (b) is a right side view of the first light guide 420, Fig.10 (c) is a cross-sectional view of the first light guide 420; the first light guide 420 includes a first light guide portion 421 and a second light guide portion 422, the first light guide portion 421 is a cylindrical structure including two bottom surfaces and a cylindrical surface, the second light guide portion 422 is an oblique cone structure including a bottom surface and a conical surface, the conical surface is the light emitting surface 423, wherein the bottom surface of the first light guide portion 421 and the bottom surface of the second light guide portion 422 are equal in area, and are used to achieve the connection between the first light guide portion 421 and the second light guide portion 422. Fig.10 As shown in (c), the second light-guiding portion 422 forms intersection lines S1 and S2 with the light-emitting surface 323 through any plane P1 of the straight line L, wherein the angle formed by the intersection line S1 and the straight line L1 is A1, and the angle formed by the intersection line S2 and the straight line L1 is A2, wherein A1 and A2 are not equal in size; in the present embodiment, at most one A1 is equal to one A2; through the above arrangement, the light-emitting surface 423 is rotationally asymmetric around the straight line L1, thereby making the light emitted from the light-emitting surface 323 unevenly distributed in space.

[0070] In some other embodiments, the above-mentioned "oblique circular cone" can be replaced with "oblique pyramid", and the circular cone is regarded as a case where the number of edges of the pyramid is infinite. In this case, the light-emitting surface is the side of the oblique truncated pyramid. In general, the light-emitting surface can be the side of an oblique cone, and the oblique cone includes an oblique circular cone and an oblique pyramid, and also includes other oblique cone structures.

[0071] In addition, the first light guide portion 421 of the first light guide 420 may also be other structures, such as a truncated pyramid, a truncated cone structure or a prism structure, etc. The second light guide portion 422 may also be an oblique truncated pyramid structure such as a truncated pyramid or a truncated pyramid. In this type of technical solution, the second light guide portion 422 includes a second bottom surface provided with a second reflective layer.

[0072] See also Fig.11 (a), (b) and (c), Fig.11 (a) is a schematic structural diagram of a fifth embodiment of the lighting device of the present application, Fig.11 (b) is a schematic structural diagram of the first light guide of the lighting device of the fifth embodiment, Fig.11(c) is a right side view of the first light guide. The lighting device 500 of this embodiment includes: a light source 510 and a first light guide 520, wherein the light source 510 is consistent with that described in the above embodiment and will not be described again. The first light guide 520 includes a first light guide portion 521 and a second light guide portion 522, wherein the cross-sectional area of ​​the second light guide portion 522 perpendicular to the central axis of the first light guide 520 gradually decreases along the direction of the light source optical axis, and the second light guide portion 522 includes a light emitting surface 523, and the light emitting surface 523 does not have rotational symmetry.

[0073] like Fig.11 As shown in (b) and (c), the first light guide portion 521 of the first light guide 520 is a quadrangular prism including two bottom surfaces and four side planes, and the two bottom surfaces are square; the second light guide portion 522 is a wedge including a bottom surface and four side surfaces, and at least part of the side surfaces are light-emitting surfaces 523. In the present embodiment, the second light guide portion 522 includes two sub-light-emitting surfaces 523a and 523b, and the orthographic projection of the intersection of the sub-light-emitting surface 523a and the sub-light-emitting surface 523b on the bottom surface of the second light guide portion 422 divides the bottom surface into two shapes of different sizes. In a specific application case, the orthographic projection of the intersection of the sub-light-emitting surface 523a and the sub-light-emitting surface 523b on the bottom surface of the second light guide portion divides the bottom surface into two shapes of the same size; the bottom surface of the second light guide portion 522 is the same in shape and size as the bottom surface of the first light guide portion 521, and is used to realize the connection between the first light guide portion 521 and the second light guide portion 522. Through the above arrangement, the light emitted from the light emitting surface 523 is evenly distributed in the space.

[0074] In some other embodiments, the second light guide portion 522 may also be other wedge-shaped structures, so that the second light guide portion includes three or more sub-light emitting surfaces, and the shape formed by the orthographic projection of the intersection line of each sub-light emitting surface on the bottom surface of the second light guide portion is changed by changing the inclination angle of each sub-light emitting surface relative to the central axis of the first light guide, so that the light emitted from the light emitting surface is unevenly distributed in space. In addition, the first light guide portion 521 of the first light guide 520 may also be other structures, such as a truncated pyramid, a truncated cone structure, or a cylindrical structure.

[0075] In summary, the first light guide portion of the first light guide may be a columnar structure or a frustum structure; the second light guide portion may be a part of a right cone structure or a right frustum structure, may be part or all of an oblique cone structure or an oblique frustum structure, or may be part or all of a wedge structure. For ease of understanding, the second light guide portion may be simply regarded as a structure formed by the spatial intersection of the right cone structure, right frustum structure, oblique cone structure, oblique frustum structure, or wedge structure and the columnar structure or frustum structure of the first light guide portion. For example, Figure 3 The second light guide portion of the first light guide is the intersection of a cylinder and a right circular cone in space. Figure 5The second light guide portion of the first light guide is the intersection of a quadrangular prism and a right circular cone in space. Figure 7 The second light guide portion of the first light guide is the intersection of a cylinder and a right circular truncated cone in space. Fig.10 The second light guide portion of the first light guide is the intersection of a cylinder and an oblique cone in space. Fig.11 The second light guide portion of the first light guide shown is the intersection of a quadrangular pyramid and a wedge in space. Examples are not given here one by one. Through this spatial overlap, the "intercepted" second light guide portion has a spatially non-rotationally symmetrical structure ( Figure 8 Except for the embodiment shown), the aspect does not have rotational symmetry, so that the spatially unevenly distributed output light can be obtained.

[0076] See also Fig.12 , Fig.12 This is a schematic diagram of the structure of the sixth embodiment of the lighting device of the present application. The lighting device 600 of this embodiment includes: a light source 610, an optical lens 640 and a first light guide 620, wherein the light source 610 is consistent with that described in the above embodiments, and the first light guide 620 can be the first light guide in any of the above embodiments (only for illustration in the figure), which will not be repeated here. The optical lens 640 is arranged on the light path between the light source 610 and the first light guide 620, and is used to collect the light emitted by the light source 620, so that the incident angle of the light emitted by the light source 610 on the first light guide 620 is less than a preset value, so that more light can enter the first light guide 620 and meet the total internal reflection angle, thereby improving the light utilization rate.

[0077] Specifically, when the first light guide portion 621 of the first light guide 520 is a columnar structure, the optical lens 640 makes the incident angle of the light incident on the first light guide 620 Wherein n is the refractive index of the first light guide 620 .

[0078] In order to further improve the brightness of the emitted light of the lighting device, in the seventh embodiment, as Fig.13 As shown, the lighting device 700 of this embodiment includes: a light source (including two sub-light sources 710 and 740), a first light guide 720 and a second light guide 750, the second light guide being the same as the first light guide described in any of the above embodiments, the first light guide 720 including a first light guide portion 721 and a second light guide portion 722, the second light guide 750 including a third light guide portion 751 and a fourth light guide portion 752, the light emitted from the sub-light source 740 is coupled into the third light guide portion 751, and is emitted from the light emitting surface of the fourth light guide portion 752; wherein the ends of the second light guide portion 722 and the fourth light guide portion 752 are relatively closely arranged, and the second light guide portion 722 and the fourth light guide portion 752 are both located at the focal position of the reflective bowl 730. Through the above arrangement, the brightness of the light emitted from the lighting device is doubled.

[0079] In a variant embodiment of the sixth embodiment, the third light guide portion of the second light guide may be bent (for example, bent into a U shape) so that the end of the fourth light guide portion is arranged opposite to the end of the second light guide portion. In this way, the two sub-light sources can be located on the same side, which facilitates circuit wiring.

[0080] See also Fig.14 , Fig.14 800 of the present embodiment comprises: a light source 810, a first light guide 820 and a reflective bowl 830, wherein the light source 810 is consistent with the light source of the above embodiment, and the first light guide 820 is any of the first light guides in the above embodiment. Figure 3 The structure of the present invention is not limited to the structure. The specific description refers to the description of the above embodiments, which will not be repeated here. The reflective bowl 830 is a curved reflective bowl, such as a parabolic reflective bowl or an ellipsoidal reflective bowl. A reflective area 831 is arranged inside the reflective bowl 830. The reflective area 831 can be formed by arranging a film layer with high reflectivity inside the reflective bowl 830, such as a reflective silver layer, a reflective aluminum layer, etc.; the second light guide portion 822 of the first light guide 820 is arranged at the focal position of the reflective bowl 830.

[0081] In this embodiment, light emitted from the light source 810 is coupled into the first light guide 820 from the first light guide portion 821 , emitted from the light emitting surface 823 of the second light guide portion 822 , and then reflected to the outside by the emission area 831 of the reflective bowl 830 to form illumination light.

[0082] Through the above arrangement, the illumination of each area of ​​the illumination light pattern formed after reflection by the reflective bowl can meet the requirements, and the light utilization rate of the illumination device is high.

[0083] In summary, the present application provides a lighting device, which includes a light source and a first light guide, wherein the second light guide portion of the first light guide includes a light-emitting surface, and by making the light-emitting surface not have rotational symmetry, the light emitted from the light-emitting surface is unevenly distributed in space, and by changing the light distribution of the light emitted by the lighting device, it is beneficial to reduce light loss and improve light utilization.

[0084] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0085] The above description is only an implementation mode of the present invention, and does not limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made by using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A lighting device, comprising: The light source and the first light guide are characterized by: The first light guide comprises a first light guide portion and a second light guide portion, the second light guide portion comprises a light emitting surface, and the light emitted by the light source is at least partially coupled into the first light guide portion and emitted from the light emitting surface of the second light guide portion; The cross-sectional area of ​​the second light guide portion perpendicular to the center line of the first light guide gradually decreases along the optical axis direction of the light source; The light-emitting surface does not have rotational symmetry; The lighting device further comprises a reflective bowl, the second light guide portion is arranged at a focal position of the reflective bowl, and the reflective bowl is used to reflect the light emitted from the light-emitting surface to the outside; The lighting device further comprises an optical lens, which is arranged on a light path between the light source and the first light guide so that the light emitted by the light source is incident at an angle of incidence of the first light guide. , where n is the refractive index of the first light guide.

2. The lighting device according to claim 1, characterized in that: The second light guide portion is a part of a right cone or a right truncated cone, and the light emitting surface of the second light guide portion is arranged as a part of the side surface of the right cone or the right truncated cone.

3. The lighting device according to claim 2, characterized in that: The axis of the right cone or right frustum is parallel to and does not overlap with the center line of the first light guide portion.

4. The lighting device according to claim 2, characterized in that: The second light guide portion further includes a first reflective surface, which is arranged as a part of the side surface of the right cone or the right frustum of a pyramid, and a combined surface of the light emitting surface and the first reflective surface has rotational symmetry.

5. The lighting device according to claim 1, characterized in that: The second light guide portion is an oblique cone or an oblique frustum, and the light emitting surface of the second light guide portion is a side surface of the oblique cone or the oblique frustum.

6. The lighting device according to claim 1, characterized in that: The second light guiding portion is a wedge-shaped body, and the light emitting surface of the second light guiding portion is at least a part of a side surface of the wedge-shaped body.

7. The lighting device according to any one of claims 1 to 6, characterized in that: The second light guide portion includes a first bottom surface and a second bottom surface that are opposite to each other. The second bottom surface is disposed at an end of the second light guide portion, and a second reflective layer is disposed on the second bottom surface.

8. The lighting device according to any one of claims 1 to 6, characterized in that: The first light guide portion is a column structure or a frustum structure; the first light guide portion and the second light guide portion are integrally formed.

9. The lighting device according to any one of claims 1 to 6, characterized in that: A cross section of the first light guide portion perpendicular to the center line of the first light guide is a square structure including two rounded corners, and an orthographic projection of a vertex of the second light guide portion within the cross section is located on a side away from the rounded corners.

10. The lighting device according to claim 8, characterized in that: The second light guiding portion includes a third reflecting surface, and the third reflecting surface and at least a portion of the side surface of the first light guiding portion are continuous surfaces.

11. The lighting device according to any one of claims 1 to 6, characterized in that: The light emitting surface is provided with a scattering structure and / or a fluorescent layer.

12. The lighting device according to any one of claims 1 to 6, characterized in that: The first light guide further comprises: a heat dissipation layer, the heat dissipation layer being arranged on at least a part of the side surface of the first light guide portion and being used for dissipating heat from the first light guide; A transparent adhesive layer is used to adhere the heat dissipation layer to the side surface of the first light guide portion so that the heat of the first light guide is transferred to the heat dissipation layer, wherein the refractive index of the transparent adhesive layer is lower than the refractive index of the first light guide.

13. The lighting device according to any one of claims 1 to 6, characterized in that: The lighting device also includes a second light guide, which includes a third light guide portion and a fourth light guide portion, and the light emitted by the light source is at least partially coupled into the third light guide portion and emitted from the light emitting surface of the fourth light guide portion, and the end of the first light guide is arranged relatively close to the end of the second light guide.

Images