lighting equipment

Abstract

To restrain increase in the number of whole installed light sources by concurrently using a light source for a plurality of illuminations even though kind of illumination is increased.SOLUTION: An illumination device comprises one or more light sources and a light guide plate. The one or more light sources are concurrently used to a plurality of illuminations. The light guide plate includes a transparent part which transmits a light emitting from the light source directly, a light collection part which takes the light emitting from the light source in inside and an emitting part which emits the light taken in the inside by the light collection part.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a lighting device. [Background technology]

[0002] Various types of lighting are known for the interior of an automobile (see, for example, Patent Documents 1 and 2). The lighting mounted on the overhead console (OHC) located on the ceiling of the interior of the vehicle generally includes room lighting that illuminates the entire driver's seat and passenger seat, and spot lighting that illuminates each of the driver's seat and passenger seat.

[0003] In addition to these features, an increasing number of vehicles in recent years are being equipped with downlights that illuminate the center console and cup holders between the driver's seat and passenger seat, as well as ambient lighting to enhance the atmosphere inside the vehicle.Ambient lighting does not illuminate a specific location, but rather creates an aesthetic impression by emitting light itself. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2018-2118 [Patent Document 2] Japanese Patent Application Laid-Open No. 2012-201346 Summary of the Invention [Problem to be solved by the invention]

[0005] However, as the number of types of lighting increases, the number of light sources such as LEDs (Light Emitting Diodes) mounted on the overhead console also increases, which results in a direct increase in the cost of the entire overhead console.

[0006] The present invention has been made in consideration of the above, and aims to provide a lighting device that can share a light source for multiple lights and suppress an increase in the total number of light sources installed, even if the number of types of lighting increases. [Means for solving the problem]

[0007] In order to solve the above-mentioned problems and achieve the object, an illumination device according to one aspect of the present invention includes one or more light sources and a light guide plate. The one or more light sources are used for multiple illuminations. The light guide plate has a transmission section that directly transmits light emitted from the light source, a lighting section that takes in the light emitted from the light source, and an emission section that emits the light taken in by the lighting section. The transmission section is a flat portion of the light guide plate located on the optical axis of the light source, the light collecting section is a linear prism provided adjacent to the transmission section, and the emission section is a microlens array provided at a position spaced apart from the linear prism.

[0008] Advantageous Effects of Invention Even if the number of types of lighting increases, the lighting device according to one aspect of the present invention can share a light source for a plurality of lighting devices, thereby preventing an increase in the total number of mounted light sources. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a diagram illustrating an example of a lighting device according to an embodiment. [Figure 2] FIG. 2 is a YY end view of FIG. [Figure 3] FIG. 3 is a plan view and a partially enlarged view of the light guide plate. [Figure 4] FIG. 4 is a diagram showing the state of light emitted from each part of the lighting device. [Figure 5] FIG. 5 is a diagram showing the base angles of the linear prisms of the light guide plate. [Figure 6] FIG. 6 is a diagram showing an example of the relationship between the base angle of the linear prism of the light guide plate and the average luminance value of the microlens array. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, lighting devices according to embodiments will be described with reference to the drawings. Note that the present invention is not limited to these embodiments. Furthermore, the dimensional relationships and ratios of elements in the drawings may differ from reality. The dimensional relationships and ratios may differ between the drawings. Furthermore, the content described in one embodiment or modification is, in principle, applicable to other embodiments or modifications in the same manner.

[0011] Fig. 1 is a diagram showing an example of a lighting device 1 according to an embodiment, looking up at a ceiling C from the seat side. Fig. 2 is a YY end view of Fig. 1.

[0012] 1 and 2, the lighting device 1 is fixed to a ceiling C and has a frame 2 with a generally rectangular shape without corners. The frame 2 is provided with generally rectangular openings 2a, 2b, and 2c through which illumination light is emitted. The end faces of the openings 2a, 2b, and 2c are tapered so that the end facing the vehicle interior is wider than the end facing the light source so as not to obstruct the light path.

[0013] The central opening 2a is for a downlight, and the left and right openings 2b and 2c are for spot lighting (opening 2b is for the seat on the left side in the figure, and opening 2c is for the seat on the right side). When the left and right spot lights are turned on simultaneously, they provide room lighting. The left and right openings 2b and 2c also serve as ambient lighting. The openings 2a, 2b, and 2c in the frame 2 clearly define the light-emitting areas of the lighting device 1 and prevent light leakage, etc. Furthermore, the shape and size of the openings 2a, 2b, and 2c make it possible to adjust the distribution of the emitted light.

[0014] Inside the lighting device 1, a flat substrate 3 is provided on the bottom side (upper side in FIG. 2, the side facing the ceiling C of the automobile), and a light source 41 such as an LED that serves as both a downlight and ambient lighting is arranged in the center on the light output side of the substrate 3. Here, there is one light source 41 that serves both as a downlight and ambient lighting, but there may be multiple light sources depending on the amount of light required.

[0015] In addition, pairs of light sources, such as LEDs for spot lighting, are provided on both sides of the substrate 3, one on the front side and one on the back side of the figure. That is, light sources 42 and 43 are provided on the front side of the left side of FIG. 2, light sources 44 and 45 are provided on the back side, and light sources 46 and 47 are provided on the front side of the right side of the figure, and light sources 48 and 49 are provided on the back side. For example, the front side light sources 42, 43 and light sources 46, 47 and the back side light sources 44, 45 and light sources 48, 49 are set to have warm colors on the front side and cool colors on the back side (or vice versa). By adjusting the ratio of the light intensities of the two, the spot lighting and room lighting can be adjusted between warm and cool colors. The light intensities of the spot lighting and room lighting are controlled by the drive currents supplied to the light sources 42, 43, light sources 44, 45, light sources 46, 47, and light sources 48, 49, respectively.

[0016] Lenses 51 and 52 are provided on the emission sides of light sources 42 and 43 on the left side, lenses 53 and 54 are provided on the emission sides of light sources 44 and 45 on the rear side, lenses 55 and 56 are provided on the emission sides of light sources 46 and 47 on the right side, and lenses 57 and 58 are provided on the emission sides of light sources 48 and 49 on the rear side. Annular Fresnel lenses 51a, 52a, 53a, 54a, 55a, 56a, 57a, and 58a are provided on the light-source-side surfaces of lenses 51, 52, 53, 54, 55, 56, 57, and 58 for focusing light, and linear prisms 51b, 52b, 53b, 54b, 55b, 56b, 57b, and 58b for tilting the optical axis are provided on the emission-side surfaces.

[0017] Furthermore, a light guide plate 7 is provided on the output side of lenses 51, 52, 53, 54, 55, 56, 57, and 58, with internal frame 6 sandwiched between them. Internal frame 6 has an opening 6a in a region facing central light source 41. An opening 6b is provided in a region corresponding to lenses 51, 52 and lenses 53, and 54 on the left side, and an opening 6c is provided in a region corresponding to lenses 55, 56 and lenses 57, 58 on the right side. Openings 6a, 6b, and 6c in internal frame 6 allow light to shine only on necessary areas and block out other areas, making the light-emitting areas clear and preventing light leakage, etc.

[0018] The light guide plate 7 is made of a transparent material such as polycarbonate or acrylic, and allows light to pass through and propagate light taken in. Linear prisms 7a1 and 7a2 are provided on the light source side of the central portion of the light guide plate 7 (opening 6a of the internal frame 6), sandwiching the portion directly below the light source 41. Microlens arrays 7b1 and 7b2 corresponding to lenses 51 and 52 and lenses 53 and 54 are provided on the light source side of the left portion of the light guide plate 7 (opening 6b of the internal frame 6). Microlens arrays 7c1 and 7c2 corresponding to lenses 55 and 56 and lenses 57 and 58 are provided on the light source side of the right portion of the light guide plate 7 (opening 6c of the internal frame 6).

[0019] FIG. 3 is a plan view and a partially enlarged view of the light guide plate 7, and the light guide plate 7 shown at the top of the figure is a view from the back side of FIG. 1. In FIG. 3, the linear prisms 7a1 and 7a2 have, for example, a substantially triangular cross section with concave and convex grooves extending in the Y-axis direction. The groove pitch is, for example, 0.05 mm. Note that the linear prisms 7a1 and 7a2 function as light collecting sections that take in light emitted from the light source, and any other prisms other than the linear prisms 7a1 and 7a2 may be used as long as they have a similar function. Furthermore, the flat portion between the linear prisms 7a1 and 7a2 functions as a transmitting section that directly transmits light emitted from the light source 41 (FIG. 2).

[0020] The microlens arrays 7b1, 7b2, 7c1, and 7c2 each have, for example, hemispherical convex portions densely arranged in a staggered pattern. The radius of the hemispheres constituting the convex portions is, for example, 0.3 mm. The microlens arrays 7b1, 7b2, 7c1, and 7c2 function as an output portion that outputs light taken in by the light collecting portion. Although spot lighting light also passes through the microlens arrays 7b1, 7b2, 7c1, and 7c2, this does not significantly affect the spot lighting. The microlens arrays 7b1, 7b2, 7c1, and 7c2 have the effect of diffusing light, which eliminates color unevenness (yellow ring) of the LEDs of the light sources 42 to 49 and widens the light distribution. Furthermore, the microlens arrays 7b1, 7b2, 7c1, and 7c2 function as an emission section that emits light taken in by the light collecting section, and any other elements may be used other than the microlens arrays 7b1, 7b2, 7c1, and 7c2 as long as they have a similar function.

[0021] Fig. 4 is a diagram showing the state of light emitted from each part of the lighting device 1. In Fig. 4, EP1 is the eye point of the passenger in the left seat, and EP2 is the eye point of the passenger in the right seat.

[0022] 4, light L1 emitted from light source 41 at a narrow angle directly downward through the flat portion of light guide plate 7 between linear prisms 7a1 and 7a2 serves as a downlight to illuminate the center console and cup holders (not shown) inside the vehicle cabin. The light distribution of the downlight is determined by the shape and size of opening 2a in frame 2, the position of light source 41, the light distribution characteristics of light source 41, etc., and can be adjusted mainly by the shape and size of opening 2a and the position of light source 41.

[0023] Light L2 and L3 emitted from light source 41 at wide angles diagonally downward to the left and right is prevented from being reflected on the surface of light guide plate 7 by linear prisms 7a1 and 7a2, and is taken inside light guide plate 7. Light L2 and L3 are totally reflected inside light guide plate 7 and spread as light L4 and L6, and then hit microlens arrays 7b1 and 7b2 and microlens arrays 7c1 and 7c2, respectively, and are emitted downward as light L5 and L7.

[0024] 4, light L5 and L7 are shown only at the ends of microlens arrays 7b1 and 7b2 and microlens arrays 7c1 and 7c2 near the center, but light L4 and L6 reflected within light guide plate 7 spreads to the outside and is scattered and emitted by microlens arrays 7b1 and 7b2 and microlens arrays 7c1 and 7c2 as a whole. The light emitted by microlens arrays 7b1 and 7b2 and microlens arrays 7c1 and 7c2 acts as ambient lighting to enhance the atmosphere in the vehicle cabin. The light intensity of the ambient lighting can be adjusted not only by controlling the drive current of light source 41, but also by the shape, size, and number of linear prisms 7a1 and 7a2, which form the light-collecting section, and the shape and size of microlens arrays 7b1, 7b2, 7c1, and 7c2, which form the light-emitting section.

[0025] In this way, it is possible to prevent an increase in the number of light sources installed, since light for both downlighting and ambient lighting is supplied by one light source 41. Note that, as mentioned above, the light source 41 may be configured with a plurality of LEDs or the like depending on the required light intensity, and in this case, the effect of preventing an increase in the number of light sources installed due to dual use is similar.

[0026] Meanwhile, light L11 emitted from light sources 42 and 44 and light L13 emitted from light sources 43 and 45 are converted into light L12 and light L14 by lenses 51 and 53 and lenses 52 and 54, respectively, and act as spot lights for the seats on the left. Similarly, light L15 emitted from light sources 46 and 48 and light L17 emitted from light sources 47 and 49 are converted into light L16 and light L18 by lenses 55 and 57 and lenses 56 and 58, respectively, and act as spot lights for the seats on the right. When both spot lights are turned on, they act as room lights.

[0027] FIG. 5 is a diagram showing the base angles α and β of the linear prism 7a1 of the light guide plate 7. That is, the base angle on the side farther from the light source 41 is α, and the base angle on the side closer to the light source is β. FIG. 6 is a diagram showing an example of the relationship between the base angles α and β of the linear prism 7a1 of the light guide plate 7 and the average luminance value of the microlens arrays 7b1 and 7b2. In FIG. 6, among the combinations shown, the average luminance value of the microlens arrays 7b1 and 7b2 when α=β=45° is 126 cd / m 2 It will be the highest.

[0028] Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications are possible without departing from the spirit of the present invention.

[0029] As described above, the lighting device according to the embodiment includes one or more light sources that are shared by multiple types of lighting, and a light guide plate that has a transmission section that directly transmits light emitted from the light source, a lighting section that takes in the light emitted from the light source, and an emission section that emits the light taken in by the lighting section. This allows the light source to be shared by multiple types of lighting, preventing an increase in the total number of light sources installed, even if the number of types of lighting increases.

[0030] The transmitting section is a flat section of the light guide plate located on the optical axis of the light source, the light collecting section is a linear prism located adjacent to the transmitting section, and the emitting section is a microlens array located at a distance from the linear prism, thereby specifically realizing the use of two types of illumination.

[0031] A pair of linear prisms are provided on both sides of the transmitting section, and a pair of microlens arrays are provided at positions spaced apart from the pair of linear prisms, thereby realizing a lighting device in which a section corresponding to a downlight is located in the center and sections corresponding to ambient lighting are located around it.

[0032] The light source and lens for spot lighting are disposed on the non-light-emitting side of the light-emitting part, thereby realizing a lighting device that provides spot lighting, downlighting, and ambient lighting.

[0033] The light guide plate also includes a frame that is disposed on the light-emitting side and has openings facing the transmitting and emitting portions. This makes the light-emitting portion of the lighting device clear and prevents light leakage. The shape and size of the openings also make it possible to adjust the distribution of the emitted light.

[0034] In addition, an internal frame is provided on the opposite side of the light guide plate frame, and the internal frame has openings at positions facing the area including the transmission section and the light collecting section and the emission section. This allows light to reach only the necessary areas and blocks out the rest, making the light emitting section clear and preventing light leakage.

[0035] Furthermore, the light-collecting section is not covered by the inner frame but is covered by the frame, which prevents the light-collecting section from appearing shiny.

[0036] Furthermore, the present invention is not limited to the above-described embodiments. Configurations in which the above-described components are appropriately combined are also included in the present invention. Furthermore, further effects and modifications can be easily derived by those skilled in the art. Therefore, the broader aspects of the present invention are not limited to the above-described embodiments, and various modifications are possible. [Explanation of symbols]

[0037] 1 lighting device, 2 frame, 2a to 2c opening, 3 substrate, 41 to 49 light source, 51 to 58 lens, 51a to 58a Fresnel lens, 51b to 58b linear prism, 6 internal frame, 6a to 6c opening, 7 light guide plate, 7a1, 7a2 linear prism, 7b1, 7b2, 7c1, 7c2 microlens array, C ceiling, L1 to L7, L11 to L18 light, EP1, EP2 eye point

Claims

1. One or more light sources that are used for multiple lighting purposes; A light guide plate; Equipped with The light guide plate is a transmission portion that directly transmits light emitted from the light source; a light collecting section that takes in light emitted from the light source; an emission section that emits light taken in by the light collecting section; and the transmission portion is a flat portion of the light guide plate located on the optical axis of the light source, the light collecting section is a linear prism provided adjacent to the transmission section, the emission unit is a microlens array provided at a position spaced apart from the linear prism, Lighting equipment.

2. One or more light sources that can be used for multiple lighting applications; A light guide plate; Equipped with The light guide plate is a transmission portion that directly transmits light emitted from the light source; a light collecting section that takes in light emitted from the light source; an emission section that emits light taken in by the light collecting section; and a frame disposed on the light emitting side of the light guide plate and having openings at positions facing the transmission portion and the light emitting portion, Lighting equipment.

3. a pair of the linear prisms are provided on both sides of the transmission section, a pair of the microlens arrays are provided at positions spaced apart from the pair of linear prisms; The lighting device according to claim 1 .

4. a spot lighting light source and a lens disposed on the non-light emitting side of the light emitting section; 4. The lighting device according to claim 1.

5. a frame disposed on the light-emitting side of the light guide plate, the frame having openings at positions facing the transmission portion and the light-emitting portion; The lighting device of claim 1 .

6. an inner frame on the opposite side of the light guide plate from the frame; the internal frame has openings at positions facing the region including the transmission section and the light collecting section and the emission section, 6. The lighting device according to claim 2 or 5.

7. The light-collecting portion is not covered by the internal frame but is covered by the frame.

7. The lighting device according to claim 6.

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