Optical structure for large-area lighting effect in a vehicle light

Abstract

This invention relates to the field of automotive lighting optical technology, and discloses an optical structure for a large-area illumination effect in automotive lights. The structure includes a light guide plate and an LED light fixedly connected to the top of the light guide plate. Collimation entrances are provided on both sides of the top wall of the light guide plate, and a 45° swept total reflection surface is located below each collimation entrance. Light guide surface two and light guide surface one are respectively provided on the top and inner top wall of the light guide plate. A microlens is installed on the front side of the light guide plate. Reflective surfaces four and three, and five and six with intersecting edges and an included angle of 90° are respectively provided at both ends of the light guide plate. This invention constructs a multi-stage total reflection and refraction light path through parallel light guide surfaces and end-mounted vertical reflective surfaces. The returning light beam is extracted and refracted by the central microlens array and emitted. Large-area uniform light emission is achieved using a small number of light sources in conjunction with a thin-walled light guide plate. This reduces visual graininess and material costs while adapting to the extremely limited assembly gaps in automotive lights.

Description

Technical Field

[0001] This invention relates to the field of automotive lighting optical technology, and in particular to an optical structure for a large-area illumination effect in automotive lights. Background Technology

[0002] Modern automotive headlight design requires the construction of large luminous surfaces to serve as nighttime driving or daytime signal indicators. Large luminous surfaces have high visual recognition for the human eye. Due to the compression of the overall vehicle aerodynamic appearance, the physical mechanical assembly gap reserved for optical components inside the headlights is gradually developing towards flattening and narrowing.

[0003] Traditional automotive headlights typically employ a direct-light-emitting physical structure with a dense array of LED light sources to meet the requirements of large-area light emission. After passing through an external light distribution lens, the densely arranged independent LED light sources form a discrete array of high-brightness light spots on the headlight's emitting surface. This array of high-brightness light spots causes uneven brightness distribution on the emitting surface and produces an abrupt visual graininess. Adding a diffuser behind the emitting surface will exacerbate the light penetration attenuation and reduce the overall optical extraction efficiency. To maintain the surface illuminance standards required by regulations, the number of LED light sources must be increased and the overall input power must be increased. The massive LED light source array drives up the manufacturing material costs of the automotive headlight electronic control system. The significant heat generated by multiple LED light sources emitting light in parallel requires a heavy metal heat sink base. The heavy metal heat sink base, combined with a multi-layer light distribution structure, makes the traditional optical assembly thick and bulky. This bulky optical assembly is difficult to install into the narrow and limited installation gaps in the vehicle body.

[0004] Therefore, this invention proposes an optical structure for large-area illumination in vehicle lights to address the shortcomings of existing technologies. Summary of the Invention

[0005] In view of the problems in the existing technology of large-area light-emitting components of vehicle lights, such as the reliance on dense LED light source arrays leading to a large internal structure volume, the appearance of discrete visual particles on the light-emitting surface, and the heavy heat dissipation base occupying the narrow assembly gap of the vehicle light due to the heat generated by multiple light sources in parallel, the present invention provides an optical structure with improved structure that can effectively solve the above problems and improve the large-area lighting effect in vehicle lights.

[0006] This invention provides an optical structure for a large-area illumination effect in a vehicle headlight, including a light guide plate and LED lights disposed on both sides of the top wall of the light guide plate. Collimation entrances are provided on both sides of the top wall of the light guide plate. The LED lights are located directly above the collimation entrances and fixedly connected to the light guide plate. Below the collimation entrances are total reflection surfaces formed by sweeping 45° angles based on parabolic surfaces. A second light guide surface is provided on the top of the light guide plate, and the inner top wall of the light guide plate is provided with... The light guide plate has a light guide surface 1, a microlens mounted on the front side of its outer wall, a reflective surface 4 mounted on the front end of its outer wall, a reflective surface 3 mounted on the rear end of its outer wall, a reflective surface 4 and a reflective surface 3 intersecting and connected at a 90° angle, a reflective surface 6 mounted on the other end of its outer wall, and a reflective surface 5 mounted on the other end of its outer wall, a reflective surface 5 intersecting and connected at a 90° angle.

[0007] Preferably, the first light guide surface and the second light guide surface are arranged parallel to each other in three-dimensional space, and the light projection direction of the collimated light inlet is parallel to the plane containing the first light guide surface and the second light guide surface. The parallel geometric arrangement is used to constrain the light beam entering the collimated light inlet to maintain the internal total internal reflection transmission path.

[0008] Preferably, the microlens is located on the back side of the middle region of the light guide plate, and the microlens is arranged in a dot array on the surface of the light guide plate. The optical physical dots distributed in the array disrupt the physical boundary condition of total internal reflection of the transmitted light beam and uniformly refract the light beam out of the front side of the light guide plate.

[0009] Preferably, the third, fourth, fifth, and sixth reflective surfaces are manufactured as an integral injection molding process with the main body of the light guide plate, avoiding mechanical seams caused by separate assembly, which could lead to light leakage of the internal total internal reflection beam.

[0010] Preferably, the number of LEDs is limited to 1 to 2. The limited number of light-emitting components, combined with the parabolic and right-angle end reflective surfaces, reduces the overall physical manufacturing material and heat dissipation substrate input cost of the light-emitting component.

[0011] Preferably, the thickness of the light guide plate is controlled between 2mm and 8mm, and the light guide plate is made of PC or PMMA material. The high light transmittance thin-walled solid medium is adapted to the narrow and flat physical pre-reserved assembly gap inside the car taillight or signal light.

[0012] This invention provides an optical structure for achieving a large-area illumination effect in vehicle headlights. It offers the following advantages: 1. In this invention, LED lights are fixedly connected above the collimated light inlets on both sides of the top wall of the light guide plate. The parabolic structure below the collimated light inlets constrains the light beam into a parallel propagation path. The parallel light beam undergoes continuous total internal reflection between the mutually parallel top light guide surface and the inner top wall light guide surface. The combination of double reflective surfaces with intersecting outer wall edges at both ends of the light guide plate and an included angle of 90 degrees controls the total internal reflection and refraction of the unexposed light beam. The returning light beam flows back to the middle area of ​​the light guide plate and is subjected to secondary extraction and refraction by the microlenses arranged in the dot array on the back. The multiple internal total internal reflection and refraction light paths combined with the microlens dot refraction physical architecture improve the overall photon extraction efficiency. The light beam is uniformly emitted in the large surface area of ​​the light guide plate, weakening the visual graininess caused by the direct light source dot array.

[0013] 2. In this invention, the thickness of the main structure of the light guide plate is limited to between 2mm and 8mm. The light propagation path is guided by the intersecting right-angle reflective surface structure at the end of the light guide plate and the microlens matrix combination interference. The entire light-emitting component relies on only two or fewer LEDs fixedly connected to the top of the light guide plate to provide the original illumination beam. The limited number of light-emitting diode components reduces the complexity of the automotive lamp circuit board layout and the material cost of electronic component manufacturing. The thin-walled design of the light guide plate optical structure carrier greatly compresses the thickness and volume of the automotive lamp assembly, adapting to the physical mechanical assembly environment with narrow and limited reserved gaps inside automotive taillights or daytime running lights. Attached Figure Description

[0014] Figure 1 This is a three-dimensional view of an optical structure for a large-area illumination effect in a vehicle headlight, as proposed in this invention. Figure 2 This is a partial structural diagram illustrating an optical structure for a large-area illumination effect in a vehicle headlight, as proposed in this invention. Figure 3 This is a partial structural diagram of an optical structure for a large-area illumination effect in a vehicle headlight, as proposed in this invention.

[0015] Among them, 1. light guide plate; 2. collimating light inlet; 3. LED light; 4. microlens; 5. light guide surface two; 6. reflective surface four; 7. reflective surface three; 8. reflective surface five; 9. reflective surface six; 10. light guide surface one. Detailed Implementation

[0016] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Example

[0017] Please refer to Figures 1 to 3 This invention provides an optical structure for large-area illumination in vehicle lights, which solves the problems of existing vehicle lights relying on dense light source arrangement, resulting in bulky structures and grainy light output.

[0018] Please refer to Figure 1 The optical structure for the large-area illumination effect in the headlights includes a light guide plate 1 and LED lights 3 fixedly connected to both sides of the top wall of the light guide plate 1. The light guide plate 1 serves as the core carrier for light transmission and is used to constrain the propagation trajectory of the internal light path. The LED lights 3 serve as light-emitting elements and are used to provide the initial beam of light to enter the interior of the light guide plate 1.

[0019] The top wall of the light guide plate 1 has collimation light inlets 2 on both sides. The LED lamp 3 is located directly above the collimation light inlet 2. Below the collimation light inlet 2 is a total reflection surface composed of a parabolic surface swept at 45°. The total reflection surface below the collimation light inlet 2 is used to accurately reflect the introduced light beam to the middle area of ​​the light guide plate 1. The parabolic structure is used to gather the divergent light beam emitted by the LED lamp 3 and convert it into a directional propagating light beam.

[0020] The top of the light guide plate 1 has a second light guide surface 5, and the inner top wall of the light guide plate 1 has a first light guide surface 10. The first light guide surface 10 and the second light guide surface 5 are arranged parallel to each other to construct a total internal reflection boundary for the light to propagate multiple times inside the light guide plate 1. A microlens 4 is installed on the front side of the outer wall of the light guide plate 1. The microlens 4 is specifically located on the back of the middle area of ​​the light guide plate 1. The microlens 4 is arranged in a dot array on the surface of the light guide plate 1 to break the total internal reflection condition of the light beam and uniformly refract the light beam out of the outer surface of the light guide plate 1.

[0021] A reflective surface 6 is installed on the front end of the outer wall of the light guide plate 1, and a reflective surface 7 is installed on the rear end of the outer wall of the light guide plate 1. The edges of the reflective surface 6 and the reflective surface 7 intersect and are connected, and the spatial angle is fixed at 90°. A reflective surface 9 is installed on the other end of the front side of the outer wall of the light guide plate 1, and a reflective surface 8 is installed on the other end of the front side of the outer wall of the light guide plate 1. The edges of the reflective surface 8 and the reflective surface 9 also intersect and are connected, and the spatial angle is fixed at 90°. The mutually perpendicular reflective surface structure is used to reflect the light beam that has not been refracted and extracted by the microlens 4 by 180° total internal reflection. The end reflection structure is used to force the residual light beam to return to the central area of ​​the light guide plate 1 to be optically extracted by the microlens 4 for a second time.

[0022] Please refer to Figure 3The end reflection structure is described in detail. In the structure at the end of the light guide plate 1 used to constrain the light beam, the reflective surfaces 3 (7), 4 (6), 5 (8), and 6 (9) are all integrally injection molded with the main body of the light guide plate 1. The integral injection molding process ensures the continuity of the light reflection interface and eliminates the light leakage phenomenon caused by splicing gaps in the separate assembly. The edges of reflective surfaces 3 (7) and 4 (6) are directly connected and the spatial right angle is guaranteed to be 90°. The edges of reflective surfaces 5 (8) and 6 (9) are also directly connected and the spatial right angle is guaranteed to be 90°. The 90° included angle structure formed by two adjacent reflective surfaces constitutes the end reflection matrix used to force the light beam to change its propagation direction.

[0023] The light projection direction of the collimated light inlet 2 is parallel to the plane containing the first light guide surface 10 and the second light guide surface 5. The light beam emitted by the LED lamp 3 is corrected by the higher-order curved surface formed by the 45° sweep of the parabolic surface below the collimated light inlet 2 and then enters the interior of the light guide plate 1. The light beam entering the interior of the light guide plate 1 propagates in parallel with the first light guide surface 10 and the second light guide surface 5 in physical space. The parallel propagating light beam satisfies the physical condition of the critical angle of total internal reflection and undergoes continuous total internal reflection between the first light guide surface 10 and the second light guide surface 5. With this multiple internal reflection optical structure, only 1 to 2 LED lamps 3 are needed to meet the illumination requirements of the entire area of ​​the light guide plate 1.

[0024] In a preferred embodiment, the microlens 4 is located on the back side of the middle region of the light guide plate 1. The microlens 4 are arranged in a dot array on the surface of the light guide plate 1. The dot array of microlenses 4 covers and is attached to the outer wall structure of the light guide plate 1. The physical microscopic protrusion structure of the microlens 4 intersects with the back plane of the light guide plate 1. The array of microlenses 4 is used to change the propagation path of the light beam and interrupt the parallel transmission state of the light inside the light guide plate 1.

[0025] As another preferred embodiment, the light guide surface 10 and the light guide surface 5 are arranged parallel to each other in three-dimensional space. The light projection direction of the collimated light inlet 2 is parallel to the plane containing the light guide surface 10 and the light guide surface 5. The parallel spatial geometric arrangement is used to constrain the propagation of the light beam, and the parallel optical boundary is used to ensure that the incident light beam meets the physical total internal reflection critical angle requirement.

[0026] In a preferred embodiment, the number of LED lights 3 is set to 1 to 2. The LED lights 3, which are fixedly connected to the top of the light guide plate 1, are arranged directly in front of the direct light inlet 2 area. The limited light source, combined with the structure of the parabolic surface and the end vertical reflective surface, is used to reduce the investment in electronic components and the cost of manufacturing and assembly materials for the overall light-emitting component.

[0027] Working principle: When the LED lamp 3 is powered on, it emits light to generate an initial beam. The initial beam enters the interior of the light guide plate 1 through the collimating light inlet 2. The parabolic structure below the collimating light inlet 2 constrains the beam to a parallel propagation state. The beam entering the interior of the light guide plate 1 maintains a parallel transmission path with the light guide surface 5 on the top of the light guide plate 1 and the light guide surface 10 on the inner top wall. The parallel beam propagates to the end of the light guide plate 1 and illuminates the reflective surface 7. The reflective surface 7 reflects the beam to the reflective surface 6 arranged at a 90° angle. The parallel alternating propagation mode includes the beam being reflected by the reflective surface 6 to the reflective surface 7. After being reflected by the right-angle reflective surface structure at the end, the beam enters the middle area of ​​the light guide plate 1 in parallel. The beam encounters the microlens 4 on the back in the middle area of ​​the light guide plate 1. The physical dot structure of the microlens 4 destroys the boundary condition of total internal reflection of the beam and refracts the beam out of the front of the light guide plate 1 to form a light-emitting surface. The light beam that passes through the total internal reflection of reflector 7 and reflector 6 and enters the middle area of ​​the light guide plate 1 does not undergo optical interference or refraction with the microlens 4. The non-interfering light beam continues to propagate along a parallel path inside the light guide plate 1 and reaches the positions of reflector 8 and reflector 9 at opposite ends. Reflector 8 and reflector 9, which are arranged at a spatial angle of 90°, perform a second total internal reflection and refraction interference on the non-interfering light beam. The light beam that has changed its deflection direction returns to the central area of ​​the light guide plate 1 along the parallel constraint path. The returning light beam encounters the physical dots of the microlens 4 again in the central area and undergoes refraction and emission. The multiple internal reflections and refractions combined with the array distribution structure of the microlens 4 improve the uniformity of illumination and the photon extraction and utilization rate. With the light guide plate 1 with a thickness between 2mm and 8mm, the collimating light inlet 2, and the right-angle reflector structures, the LED lights 3 with a fixed connection number between 1 and 2 complete the smooth conversion from point light source to surface light source.

[0028] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An optical structure for a large-area lighting effect in a vehicle headlight, comprising a light guide plate (1), wherein LED lights (3) are provided on both sides of the top wall of the light guide plate (1); Its features are, The light guide plate (1) has collimation light inlet ports (2) on both sides of its top wall. The LED lamp (3) is located directly above the collimation light inlet ports (2) and is fixedly connected to the light guide plate (1). The top of the light guide plate (1) has a second light guide surface (5). The inner top wall of the light guide plate (1) has a first light guide surface (10). The front side of the outer wall of the light guide plate (1) is equipped with a microlens (4). The front end of the outer wall of the light guide plate (1) is equipped with a fourth reflective surface (6). The rear end of the outer wall of the light guide plate (1) is equipped with a third reflective surface (7).

2. The optical structure for a large-area illumination effect in a vehicle headlight according to claim 1, characterized in that, The fourth (6) of the light guide plate intersects and is connected to the third (7) at an angle of 90°. The other end of the outer wall of the light guide plate (1) is equipped with a sixth (9) and a fifth (8). The fifth (8) of the light guide plate (1) intersects and is connected to the sixth (9) at an angle of 90°. The first (10) of the light guide plate and the second (5) of the light guide plate are arranged parallel to each other.

3. The optical structure for a large-area illumination effect in a vehicle headlight according to claim 1, characterized in that, The microlens (4) is located on the back side of the middle region of the light guide plate (1).

4. The optical structure for a large-area illumination effect in a vehicle headlight according to claim 2, characterized in that, The three reflective surfaces (7), four reflective surfaces (6), five reflective surfaces (8), and six reflective surfaces (9) are integrally injection molded with the light guide plate (1).

5. The optical structure for a large-area illumination effect in a vehicle headlight according to claim 1, characterized in that, The microlenses (4) are arranged in a dot array on the surface of the light guide plate (1).

6. The optical structure for a large-area illumination effect in a vehicle headlight according to claim 1, characterized in that, The light projection direction of the collimated light inlet (2) is parallel to the plane containing the first light guide surface (10) and the second light guide surface (5).

7. The optical structure for a large-area illumination effect in a vehicle headlight according to claim 1, characterized in that, The number of LED lights (3) is 1 to 2.

8. The optical structure for a large-area illumination effect in a vehicle headlight according to claim 1, characterized in that, The thickness of the light guide plate (1) is between 2mm and 8mm.

9. The optical structure for a large-area illumination effect in a vehicle headlight according to claim 1, characterized in that, The light guide plate (1) is made of PC or PMMA material.

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