Small projection vehicle-mounted reading lamp system based on TIR lens

Abstract

The invention discloses a TIR lens-based small projection vehicle-mounted reading lamp system, which relates to the technical field of projection lamps and comprises an LED light source, a TIR lens, a carving plate and a projection lens which are sequentially arranged along an optical axis, the LED light source, the TIR lens, the carving plate and the projection lens are all positioned and connected through a preset optical support, one end, close to the LED light source, of the TIR lens is a light incident surface of the TIR lens, and one end, close to the carving plate, of the TIR lens is a light emergent surface of the TIR lens. The function limitation of single illumination of a traditional vehicle-mounted reading lamp is broken through, and the two core functions of reading illumination and logo projection are integrated through the same optical system. According to the two-in-one function design, an independent lighting module and an independent projection module do not need to be arranged in a vehicle-mounted system, the number of vehicle-mounted electronic elements is reduced, the complexity of a whole vehicle electrical system is reduced, and meanwhile diversified use scenes are provided for users.

Description

Technical Field

[0001] This invention relates to the field of projection lamp technology, and more specifically to a small projection vehicle-mounted reading lamp system based on a TIR lens. Background Technology

[0002] In the field of automotive interior lighting, automotive reading lights, as standard components of vehicles, primarily function to provide localized directional lighting for occupants when the vehicle is in motion or parked, meeting short-range lighting needs such as reading and searching for items inside the vehicle. They are widely used in various vehicle types, including passenger cars, commercial vehicles, and SUVs. From a technological standpoint, existing automotive reading light optical systems are mostly designed around a single light source plus a basic focusing or diffuser lens, working in conjunction with a power supply module and control components to achieve the lighting function. While some products have been optimized in terms of dimming accuracy, installation flexibility, and energy consumption control with technological advancements, they still generally suffer from limitations such as limited functionality and insufficient adaptability to different scenarios, making it difficult to meet diverse user needs and the desire for personalized brand expression.

[0003] The aforementioned shortcomings not only reduce the flexibility and user experience of in-vehicle reading lights, but also prevent them from meeting automakers' demands for branded interior design details and adapting to users' emergency lighting needs in various scenarios inside and outside the vehicle. Therefore, there is an urgent need for an in-vehicle reading light optical system that integrates "in-vehicle reading lighting and logo projection functions" and whose optical parameters and power supply methods are adapted to multiple scenarios to address the deficiencies of existing technologies. Summary of the Invention

[0004] The purpose of this invention is to provide a small projection vehicle reading light system based on a TIR lens, which overcomes the shortcomings of existing optical systems that only offer single-function lighting. It integrates a logo projection module on top of the lighting function, and through optimized optical path design, achieves clear projection of brand logos, enhances product differentiation competitiveness, meets the brand communication needs of car companies and the personalized needs of users, and solves the technical problems mentioned in the background.

[0005] To solve the above-mentioned technical problems, the present invention specifically provides the following technical solution:

[0006] A small projection vehicle-mounted reading light system based on a TIR lens includes an LED light source, a TIR lens, a stencil, and a projection lens arranged sequentially along an optical axis. The LED light source, TIR lens, stencil, and projection lens are all positioned and connected by a preset optical bracket. The end of the TIR lens closer to the LED light source is the light-incident surface of the TIR lens, and the end of the TIR lens closer to the stencil is the light-exit surface of the TIR lens.

[0007] Furthermore, the divergence angle of the LED light source is 120°.

[0008] Furthermore, the TIR lens is composed of a first refractive surface, a total reflection surface, and a second refractive surface. The first refractive surface is disposed on the light-incident surface of the TIR lens, the second refractive surface is disposed on the light-outceasing surface of the TIR lens, and the total reflection surface is disposed on the inner side of the TIR lens and is parabolic in shape.

[0009] Furthermore, the TIR lens is made of PMMA material.

[0010] Furthermore, the light-incident surface of the TIR lens has a concave structure.

[0011] Furthermore, the projection lens is composed of a first lens, a cemented doublet lens, an aperture stop, a second lens, and a third lens. The aperture stop is located in the middle of the projection lens, the first lens is located at the end of the projection lens closer to the engraving plate, the third lens is located at the end of the projection lens away from the engraving plate, the cemented doublet lens is located between the first lens and the aperture stop, and the second lens is located between the aperture stop and the third lens.

[0012] Compared with the prior art, the present invention has the following advantages:

[0013] 1. This invention breaks through the functional limitations of traditional vehicle reading lights, which only provide illumination. It integrates two core functions—reading illumination and logo projection—through a single optical system. When the system is used for reading illumination, the uniformly collimated beam output from the TIR lens provides a comfortable lighting effect and avoids glare. When switching to projection mode, the light, after being uniformly collimated by the TIR lens, illuminates the projected logo, which is then projected as an image through the projection lens. This dual-function design eliminates the need for separate lighting and projection modules in the vehicle system, reducing the number of in-vehicle electronic components, lowering the complexity of the overall vehicle electrical system, and providing users with diverse usage scenarios.

[0014] 2. In terms of light processing performance, this invention uses a single lens to achieve the functions of light homogenization and collimation of the light source. Specifically, the incident surface of the TIR lens adopts a concave structure that matches the 120° divergence angle of the LED light source, which can efficiently collect light emitted from various angles of the LED light source, solving the problem of uneven light spot in Lambertian LED light sources. The parabolic total reflection surface and the freeform surface of the second refractive surface inside the TIR lens work together to ensure that light with a small divergence angle is collimated through two refractions, while light with a large divergence angle is transmitted and output after total internal reflection, ultimately forming an output beam with high uniformity and good collimation.

[0015] 3. Regarding the projection function, the double cemented lens design formed by two cemented lenses in this invention effectively corrects chromatic aberration. Combined with the lens structure of positive and negative optical power combination, it can clearly magnify the logo projected through the stereo and project it to a distance, with stable image quality, meeting the visual needs of brand display in in-vehicle scenarios. Attached Figure Description

[0016] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are merely exemplary, and those skilled in the art can derive other embodiments based on the provided drawings without creative effort.

[0017] Figure 1 This invention provides a schematic diagram of the overall structure of a small projection vehicle-mounted reading light system based on a TIR lens;

[0018] Figure 2 A schematic diagram of the TIR lens provided for this invention;

[0019] Figure 3 A schematic diagram of the projection lens provided for this invention;

[0020] Figure 4 The optical path, spot, and angle distribution diagram of the TIR lens provided by the present invention;

[0021] Figure 5 A dot matrix diagram of projection lens imaging provided by the present invention;

[0022] Figure 6 The distortion diagram of the projection lens image provided by the present invention.

[0023] The labels in the diagram represent the following:

[0024] 1. LED light source; 2. TIR lens; 21. First refractive surface; 22. Total reflection surface; 23. Second refractive surface; 3. Plate; 4. Projection lens; 41. First lens; 42. Cemented doublet lens; 43. Aperture; 44. Second lens; 45. Third lens; 5. Optical axis. Detailed Implementation

[0025] The technical solutions of 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.

[0026] The concepts involved in this application will first be described with reference to the accompanying drawings. It should be noted that the following descriptions of various concepts are only for the purpose of making the content of this application easier to understand and do not constitute a limitation on the scope of protection of this application; furthermore, the embodiments and features in the embodiments of this application can be combined with each other unless otherwise specified. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0027] like Figures 1 to 6 As shown, this invention provides a small projection vehicle-mounted reading light system based on a TIR lens, including an LED light source 1, a TIR lens 2, a stencil 3, and a projection lens 4 arranged sequentially along an optical axis 5; wherein, the optical axis 5 is the optical path in existing projection technology. To clarify the arrangement path of the LED light source 1, TIR lens 2, stencil 3, and projection lens 4, the following is provided in the appendix. Figure 1 The optical axis 5 is shown in the diagram. This is existing technology and will not be described in detail here. The LED light source 1, TIR lens 2, engraving plate 3, and projection lens 4 are all positioned and connected by a preset optical bracket. The end of the TIR lens 2 closest to the LED light source 1 is the light-incident surface of the TIR lens 2, and the end of the TIR lens 2 closest to the engraving plate 3 is the light-exit surface of the TIR lens 2. The LED light source 1, TIR lens 2, engraving plate 3, and projection lens 4 are positioned and connected by a preset optical bracket to form a complete illumination and projection optical system, which can realize reading illumination and logo projection functions. The optical structure is compact, and a single TIR lens 2 achieves uniform light and collimation of the LED light source 1, reducing the complexity of the optical axis 5.

[0028] Specifically, the divergence angle of LED light source 1 is 120°. LED light source 1 is an approximate Lambertian light source with a divergence angle of 120°, possessing a large beam divergence angle. Lambertian light sources follow the cosine law of light emission; at a large divergence angle of 120°, the light naturally diffuses widely into space, achieving basic uniform illumination without the need for complex optical structures. In automotive reading light scenarios, it can cover the entire page of a book or the passenger reading area, avoiding localized overbrightness or dimness, meeting the needs of comfortable reading for the human eye.

[0029] Specifically, the TIR lens 2 is composed of a first refractive surface 21, a total reflection surface 22, and a second refractive surface 23. The first refractive surface 21 is disposed on the light-incident surface of the TIR lens 2, the second refractive surface 23 is disposed on the light-outceasing surface of the TIR lens 2, and the total reflection surface 22 is disposed on the inner side of the TIR lens 2 and is parabolic in shape.

[0030] Specifically, the TIR lens 2 is made of PMMA material. The TIR lens 2 is made of high light transmittance PMMA, which is polymethyl methacrylate, and the entire TIR lens 2 is integrally molded by injection molding.

[0031] Specifically, the light-incident surface of the TIR lens 2 is a concave structure. The first refractive surface 21 matches the 120° divergence angle of the LED light source 1, which can efficiently collect light emitted from the LED light source 1 at various angles; the second refractive surface 23 is a free-form surface design, which, combined with the total reflection surface 22 inside the TIR lens 2, achieves the dual functions of collimation and uniform light distribution. Compared with the traditional "lens + reflector" combination structure, a single TIR lens 2 reduces the number of optical elements, shortens the overall optical system size, and is suitable for installation in confined automotive spaces.

[0032] Specifically, the projection lens 4 is composed of a first lens 41, a cemented doublet lens 42, an aperture 43, a second lens 44, and a third lens 45. The aperture 43 is located in the middle of the projection lens 4, the first lens 41 is located at the end of the projection lens 4 near the plate 3, the third lens 45 is located at the end of the projection lens 4 away from the plate 3, the cemented doublet lens 42 is located between the first lens 41 and the aperture 43, and the second lens 44 is located between the aperture 43 and the third lens 45.

[0033] Light rays with a small divergence angle emitted from LED light source 1 pass through the transmission part at the center of TIR lens 2, namely the first refractive surface 21, the total reflection surface 22, and the second refractive surface 23. After being refracted twice, they are collimated and output from the center part of TIR lens 2.

[0034] The light emitted from LED light source 1, with a large divergence angle, undergoes total internal reflection at the sidewall of TIR lens 2 before being transmitted and collimated. A plate 3 containing the brand logo to be projected is placed behind TIR lens 2. This plate 3 is illuminated by collimated light and projected onto a distant location through a small projection lens 4. Projection lens 4 consists of five lenses and an aperture 43, two of which are cemented together to correct chromatic aberration, forming a cemented doublet lens 42. The combination of positive and negative optical powers of the first lens 41, cemented doublet lens 42, aperture 43, second lens 44, and third lens 45 magnifies and projects the logo image from plate 3 onto a distant location, resulting in a simple and compact structure.

[0035] This invention improves structural compactness through modular integration and optical path optimization. As shown in the attached diagram, the light source, collimation and homogenization module, and imaging output module are arranged sequentially along the optical path. It adopts a core optical architecture of "a single lens plus a five-element projection lens," significantly simplifying the optical path design. Specifically, the TIR lens 2, through an integrated refraction-total reflection-refraction structure, replaces the traditional "lens + reflector" combination, effectively reducing the number of optical components and shortening the overall axial dimension of the optical system. The projection lens 4 achieves imaging using only a combination of positive and negative optical powers from five lenses (including two cemented lenses), avoiding complex multi-element lens designs. This compact design perfectly fits the limited installation space in automotive interiors, reducing system integration difficulty and improving the flexibility of vehicle interior layout.

[0036] In terms of light processing performance, this invention uses a single lens to achieve the functions of uniform light and collimation of the light source. Among them, the light incident surface of the TIR lens 2 adopts a concave structure that matches the 120° divergence angle of the LED light source 1, which can efficiently collect the light emitted from the LED light source 1 at various angles and solve the problem of uneven light spot of the Lambertian LED light source 1. The parabolic total reflection surface 22 and the free-form surface of the second refractive surface 23 inside the TIR lens 2 work together to collimate the light with a small divergence angle through two refractions, and the light with a large divergence angle is transmitted and output after total internal reflection, ultimately forming an output beam with high uniformity and good collimation.

[0037] For the projection function, the design of the double cemented lens 42 formed by two cemented lenses effectively corrects chromatic aberration. Combined with the lens structure of positive and negative optical power combination, it can clearly magnify the logo projected through the plate 3 and project it to a distance. The image quality is stable and meets the visual needs of brand display in the car scene.

[0038] This invention overcomes the limitations of traditional vehicle reading lights that only provide single-function illumination, integrating both reading lighting and logo projection into a single optical system. When used for reading lighting, the uniformly collimated beam output from the TIR lens 2 provides comfortable illumination and avoids glare. When switched to projection mode, the light, after being collimated and uniformly distributed by the TIR lens 2, illuminates the logo projection plate 3, which is then projected onto the image through the projection lens 4. This dual-function design eliminates the need for separate lighting and projection modules in the vehicle system, reducing the number of in-vehicle electronic components, lowering the complexity of the overall vehicle electrical system, and providing users with diverse usage scenarios, thus enhancing the product's added value.

[0039] The embodiments and / or implementation methods described above are merely preferred embodiments and / or implementation methods for implementing the technology of the present invention, and are not intended to limit the implementation methods of the technology of the present invention in any way. Any person skilled in the art can make some modifications or alterations to other equivalent embodiments without departing from the scope of the technical means disclosed in the content of the present invention, but they should still be regarded as the technology or embodiments that are substantially the same as the present invention.

[0040] This document uses specific examples to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the methods and core ideas of this application. The above descriptions are only preferred embodiments of this application. It should be noted that due to the limitations of written expression, while there are objectively infinite specific structures, those skilled in the art can make several improvements, modifications, or changes without departing from the principles of this application, and can also combine the above technical features in an appropriate manner. These improvements, modifications, changes, or combinations, or the direct application of the inventive concept and technical solution to other situations without modification, should all be considered within the scope of protection of this application.

Claims

1. A small projection vehicle-mounted reading light system based on a TIR lens, characterized in that, It includes an LED light source (1), a TIR lens (2), a stencil (3), and a projection lens (4) arranged sequentially along the optical axis (5); the LED light source (1), TIR lens (2), stencil (3), and projection lens (4) are all positioned and connected by a preset optical bracket. The end of the TIR lens (2) near the LED light source (1) is the light-incident surface of the TIR lens (2), and the end of the TIR lens (2) near the stencil (3) is the light-exit surface of the TIR lens (2).

2. The small projection vehicle-mounted reading light system based on a TIR lens according to claim 1, characterized in that, The divergence angle of the LED light source (1) is 120°.

3. A small projection vehicle-mounted reading light system based on a TIR lens according to claim 1, characterized in that, The TIR lens (2) is composed of a first refractive surface (21), a total reflection surface (22), and a second refractive surface (23). The first refractive surface (21) is located on the light-incident surface of the TIR lens (2), and the second refractive surface (23) is located on the light-outceasing surface of the TIR lens (2). The total reflection surface (22) is located on the inner side of the TIR lens (2) and the total reflection surface (22) is parabolic.

4. A small projection vehicle-mounted reading light system based on a TIR lens according to claim 3, characterized in that, The TIR lens (2) is made of PMMA material.

5. A small projection vehicle-mounted reading light system based on a TIR lens according to claim 2, characterized in that, The light-incident surface of the TIR lens (2) is a concave structure.

6. A small projection vehicle-mounted reading light system based on a TIR lens according to claim 4, characterized in that, The projection lens (4) is composed of a first lens (41), a cemented doublet lens (42), an aperture (43), a second lens (44), and a third lens (45). The aperture (43) is located in the middle of the projection lens (4). The first lens (41) is located at the end of the projection lens (4) near the engraving plate (3). The third lens (45) is located at the end of the projection lens (4) away from the engraving plate (3). The cemented doublet lens (42) is located between the first lens (41) and the aperture (43). The second lens (44) is located between the aperture (43) and the third lens (45).

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