Reflection structure for infrared rays, and lighting device

Abstract

This invention suppresses visibility of a reflection structure for infrared rays from human eyes while efficiently reflecting infrared rays from the outside. This reflection structure for infrared rays is provided with: an infrared transmission unit that transmits infrared rays and absorbs visible light; and a reflection unit that is disposed on the back side of the infrared transmission unit and that reflects the infrared rays transmitted through the infrared transmission unit. According to this configuration, infrared rays emitted from an external light source (for example, an infrared sensor) and incident on the reflection structure for infrared rays pass through the infrared transmission unit, are retroreflected or diffuse-reflected by the reflection unit, and are directed to the external light source.

Description

Infrared reflective structure, lighting device

[0001] The technology disclosed in this specification relates to an infrared reflective structure and a lighting device.

[0002] With the advancement of autonomous driving (AD) systems and advanced driver assistance systems (ADAS), research and development of light detection and ranging (LiDAR) is underway as one of the measurement devices used to grasp the surrounding environment and estimate the vehicle's position while the vehicle is traveling. LiDAR includes a projector that projects laser light onto a measurement target and a photoreceiver that receives the light reflected from the laser light that is reflected back from the measurement target. LiDAR measures the distance to the measurement target based on the difference between the timing at which the projector emits the laser light and the timing at which the photoreceiver receives the reflected light (see Patent Document 1 below).

[0003] JP 2010-185769 A

[0004] In recent years, measurement devices using infrared rays (such as LiDAR) have been studied to accurately measure objects, for example, at night or in rainy weather. For example, a vehicle equipped with an infrared LiDAR emits infrared rays to perform sensing (determine the presence or absence of a vehicle, measure the distance to a surrounding vehicle, etc.) of surrounding vehicles (e.g., other vehicles traveling ahead or to the side) while traveling. However, the infrared rays emitted from the LiDAR are absorbed or diffusely reflected by the surface of the vehicle body, resulting in a decrease in the specular reflection component. As a result, the ratio of the amount of infrared light reflected by the vehicle body and returning to the LiDAR to the amount of infrared light emitted from the LiDAR is low, which may prevent accurate sensing using infrared rays.

[0005] This specification discloses a technique that can solve the above-mentioned problems.

[0006] The technology disclosed in this specification can be realized, for example, in the following forms.

[0007] (1) The infrared reflective structure disclosed in the present specification is an infrared reflective structure that includes an infrared-transmitting portion that transmits infrared rays and absorbs visible light, and a reflective portion that is disposed on the back side of the infrared-transmitting portion and reflects the infrared rays that have transmitted through the infrared-transmitting portion.

[0008] In this configuration, infrared rays emitted from an external light source (e.g., an infrared sensor) and incident on the infrared reflective structure pass through the infrared transmitting portion, are reflected by the reflecting portion, and return to the external light source. On the other hand, visible light rays incident on the infrared reflective structure from the outside are absorbed by the infrared transmitting portion. Therefore, with this configuration, it is possible to efficiently reflect infrared rays from the outside while reducing the visibility of the infrared reflective structure to the human eye.

[0009] (2) In the infrared reflective structure, the reflective portion may have a retroreflective structure that retroreflects infrared light that has passed through the infrared transmitting portion. With this configuration, the efficiency of reflecting infrared light toward an external light source can be improved, compared to a configuration in which the reflective portion does not have a retroreflective structure, for example.

[0010] (3) In the infrared reflective structure, the reflecting portion may have a reflecting surface that internally reflects the infrared light transmitted through the infrared transmitting portion, and the reflecting surface may be formed with a reflecting material having a higher light reflectance than the reflecting surface. With this configuration, it is possible to improve the efficiency of reflecting infrared light toward an external light source, compared to a configuration in which the reflecting portion does not have a reflecting material, for example.

[0011] (4) In the infrared reflective structure, the reflector may be a light-transmitting member having a reflective surface that internally reflects infrared rays that have passed through the infrared-transmitting member, and the infrared-transmitting member may be a plate-shaped member that is disposed along the front surface of the reflector. With this configuration, compared to a configuration in which the entire infrared reflective structure is formed from an infrared-transmitting material, the amount of infrared-transmitting material used can be reduced, and the infrared reflective structure can be made less visible to the human eye while efficiently reflecting infrared rays from outside.

[0012] (5) A lighting device disclosed in the present specification includes a lamp and the infrared reflective structure. With this configuration, it is possible to efficiently reflect infrared rays from outside while reducing the visibility of the infrared reflective structure to the human eye.

[0013] (6) In the lighting device described above, the lamp may be a rear lamp mounted on a rear portion of a vehicle, and the infrared reflective structure may be provided on the rear lamp. According to this configuration, infrared rays from outside are efficiently reflected by the infrared reflective structure provided on the rear lamp. As a result, for example, the rear lamp improves visibility from following vehicles equipped with a camera or the like that emits infrared light to recognize objects ahead.

[0014] (7) In the above lighting device, the lamp may be an elongated lamp extending in a predetermined direction, and the infrared reflective structure may be provided on the elongated lamp. According to this configuration, infrared rays from outside are efficiently reflected by the infrared reflective structure provided on the elongated lamp. Therefore, for example, it is possible to prevent a following vehicle equipped with a camera or the like that emits infrared light to recognize objects ahead from being unable to recognize the position of the infrared reflective structure due to light emission from the elongated lamp.

[0015] The technology disclosed in this specification can be realized in various forms, for example, in the form of an infrared reflective structure, a lighting device having an infrared reflective structure, etc.

[0016] 4(A) is a point cloud image of the reflex reflector of this embodiment, and FIG. 4(B) is a point cloud image of a reflex reflector of a comparative example. FIG. 4(B) is a point cloud image of a reflex reflector of a comparative example. FIG. 4(A) is a point cloud image of the reflex reflector of this embodiment, and FIG. 4(B) is a point cloud image of a reflex reflector of a comparative example. FIG. 4(B) is a point cloud image of the reflex reflector of a second embodiment. FIG. 4(B) is a point cloud image of the reflex reflector of a third embodiment. FIG. 4(B) is a point cloud image of the reflex reflector of a fourth embodiment. FIG. 4(B) is a point cloud image of the reflex reflector of a fifth embodiment.

[0017] A. First Embodiment: A-1. Example of Use of Reflex Reflector: FIG. 1 shows an example of sensing by a measuring device 50 using infrared rays L (infrared light, infrared laser light). The measuring device 50 of this embodiment is a LiDAR. The measuring device 50 is mounted on a vehicle M1 equipped with, for example, an AD (automated driving system) or an ADAS (advanced driver assistance system). The measuring device 50 assists in the detection of objects such as people and surrounding vehicles (M2, M3) while the vehicle M1 is traveling, and provides various information to other devices and users that is useful for ensuring the safety of the driver of the vehicle M1 and those around the vehicle M1, and for reducing damage to surrounding objects while the vehicle M1 is being driven.

[0018] The reflex reflector 10 of this embodiment is a reflector that efficiently reflects infrared rays L from the measuring device 50 while suppressing visibility to the human eye. The reflex reflector 10 is an example of an infrared reflective structure.

[0019] In the example of FIG. 1 , a measuring device 50 is mounted on the front end of vehicle M1, and infrared rays L1 are emitted from the measuring device 50. Vehicle M1 is traveling forward (upward in the plane of FIG. 1 ). A nearby vehicle M2 is traveling ahead of vehicle M1, heading in the same forward direction as vehicle M1. A pair of second reflex reflectors 10B, 10B are disposed on both left and right ends of the rear end of nearby vehicle M2. Nearby vehicle M3 is traveling ahead of vehicle M1 in the oncoming lane, heading backward in the opposite direction from vehicle M1 (downward in the plane of FIG. 1 ). A pair of first reflex reflectors 10A, 10A are disposed on both left and right ends of the front end of nearby vehicle M3. Each first reflex reflector 10A extends from the front end of nearby vehicle M3 to its side. This allows the first reflex reflector 10A to be detected by the measuring device 50 not only from the front of the vehicle M1 but also from the side of the vehicle M1.

[0020] Fig. 2 shows an example of the installation of the reflex reflector 10. Fig. 2 shows the rear end of a nearby vehicle M2. A tail lamp device 20C, a pair of rear combination lamps 20B, and a pair of fourth reflex reflectors 10D, 10D are mounted on the rear end of the nearby vehicle M2. The tail lamp device 20C and the rear combination lamps 20B are examples of lighting devices.

[0021] The tail lamp device 20C is disposed above the rear window 25 of the nearby vehicle M2. The tail lamp device 20C includes a tail lamp 22C and a pair of third reflex reflectors 10C. The tail lamp 22C has a shape that extends in the left-right direction and includes a light source (e.g., an LED). One of the third reflex reflectors 10C is disposed adjacent to the right side of the tail lamp 22C, and the other third reflex reflector 10C is disposed adjacent to the left side of the tail lamp 22C. The tail lamp 22C is an example of a lamp.

[0022] One rear combination lamp 20B is disposed on the lower right side of the rear window 25, and the other rear combination lamp 20B is disposed on the lower left side of the rear window 25. Each rear combination lamp 20B has a second reflex reflector 10B and a backup lamp 22B. Each backup lamp 22B has a light source (e.g., an LED or an incandescent lamp). Each second reflex reflector 10B is disposed inside the backup lamp 22B. The backup lamp 22B is an example of a lamp.

[0023] One of the fourth reflex reflectors 10D is disposed below one of the rear combination lamps 20B, and the other fourth reflex reflector 10D is disposed below the other rear combination lamp 20B. Each of the fourth reflex reflectors 10D is, for example, red.

[0024] A-2. Reflex Reflector Configuration: Figure 3 shows the configuration of the reflex reflector 10 in this first embodiment as seen from the side. The measuring device 50 shown in this figure is a schematic diagram, and the size relationship with the measuring device 50 differs from the actual size. In the example of Figure 3, the shape of the reflex reflector 10 is flat, but this is not limited to this and it may be curved, for example. The reflex reflector 10 has an infrared transmitting portion 12, a reflecting portion 14, and a reflecting material 17. Note that the first to fourth reflex reflectors 10A to 10D have the same configuration as the reflex reflector 10 described below.

[0025] The infrared transmitting portion 12 is disposed on the frontmost surface of the reflex reflector 10 and transmits infrared rays L and absorbs visible light. Specifically, the infrared transmitting portion 12 is plate-shaped and forms the front surface 13 (the outer surface facing the outside, such as the surrounding vehicle M2) of the reflex reflector 10. The front surface 13 of the infrared transmitting portion 12 is generally flat, but is not limited to this and may be curved, for example.

[0026] The infrared transmitting portion 12 is made of an infrared transmitting material that transmits light in the infrared region, and includes materials such as germanium (Ge), chalcogenide glass, and silicon (Si).

[0027] The infrared transmitting portion 12 is configured to absorb light in the visible light region. Specifically, the color of the infrared transmitting portion 12 is a visible light absorbing color overall. A visible light absorbing color is a color that easily absorbs visible light, such as black. Note that the visible light absorbing color is not limited to black, and may be a mixture of black and another color (such as dark red). As long as at least the color of the front surface 13 of the infrared transmitting portion 12 is a visible light absorbing color, the entire infrared transmitting portion 12 does not have to be a visible light absorbing color. In short, it is sufficient for the infrared transmitting portion 12 to have a higher visible light absorption rate than a typical reflex reflector for visible light.

[0028] The reflecting section 14 is disposed on the rear side of the infrared transmitting section 12 and retroreflects the infrared light L1 that has passed through the infrared transmitting section 12. Specifically, the rear surface 15 of the infrared transmitting section 12 has a cube-corner shape. The rear surface 15 of the infrared transmitting section 12 has a plurality of cube corners formed thereon, each of which is made up of three mutually orthogonal reflecting surfaces 16. As shown in FIG. 3 , the infrared light L1 that has passed through the infrared transmitting section 12 is reflected by the cube corners (reflecting surfaces 16) to become reflected light L2 that travels toward the light source of the infrared light L1 and passes through the infrared transmitting section 12.

[0029] The reflector 17 is formed on the rear surface 15 (reflecting surface 16). The reflector 17 is made of a material having a higher reflectance than the reflecting surface 16 (infrared transmitting portion 12). The reflector 17 is formed by, for example, metal deposition, a reflective film, a metal sheet, or the like. The reflector 17 is formed on the entire rear surface 15.

[0030] A-3. Advantages of this embodiment: In this embodiment, infrared rays L1 emitted from the measuring device 50 and incident on the reflex reflector 10 pass through the infrared transmitting portion 12, are reflected by the reflecting portion 14, and proceed toward the measuring device 50 (see FIG. 3). On the other hand, visible light incident on the reflex reflector 10 from the outside is absorbed by the infrared transmitting portion 12. Therefore, according to this embodiment, it is possible to efficiently reflect infrared rays L1 from the measuring device 50 while reducing the visibility of the reflex reflector 10 to the human eye.

[0031] Fig. 4(A) shows a point cloud image of the reflex reflector 10 of this embodiment, and Fig. 4(B) shows a point cloud image of a reflex reflector 60 of a comparative example. The reflex reflector 60 of the comparative example is a black plate that does not transmit infrared rays. Each of the reflex reflectors 10 and 60 was fixed on a tripod N, and measurements were performed using the measuring device 50. As shown in Fig. 4(B), a point cloud image of the reflex reflector 60 of the comparative example was not acquired. This is thought to be because the reflex reflector 60 is a black plate and therefore has low reflectivity of infrared rays L1 from the measuring device 50.

[0032] Meanwhile, as shown in Fig. 4(A), a point cloud image of the reflex reflector 10 of this embodiment was acquired. The reflex reflector 10 has an infrared-transmitting portion 12 that transmits infrared rays L1, and a reflective portion 14 on its back surface (see Fig. 3). Therefore, the reflex reflector 10 has a higher reflectance of the infrared rays L1 from the measuring device 50 than the reflex reflector 60. This means that the reflex reflector 10 can be detected and the distance measured with high accuracy by the measuring device 50.

[0033] In the example of Fig. 2, the third reflex reflector 10C in the tail lamp device 20C can efficiently return infrared rays L1 from the measuring device 50 back to the measuring device 50. The color of the infrared-transmitting portion 12 of the third reflex reflector 10C is a visible light-absorbing color (e.g., black), making the reflex reflector 10 inconspicuous. This prevents the presence of the reflex reflector 10 from affecting the design of the external appearance of the surrounding vehicle M2. Also, like the fourth reflex reflector 10D, a dummy rear fog lamp can be given the function of reflecting infrared rays.

[0034] In this embodiment, the reflecting portion 14 has a retroreflective structure that retroreflects the infrared light L1 that has passed through the infrared transmitting portion 12 (see FIG. 3 ). According to this embodiment, the reflection efficiency of the infrared light L2 toward the measuring device 50 can be improved compared to, for example, a configuration in which the reflecting portion 14 does not have a retroreflective structure (a diffuse reflection structure or a specular reflection structure).

[0035] In this embodiment, a reflecting material 17 is formed on the reflecting surface 16 of the reflecting portion 14 (see FIG. 3 ). According to this embodiment, the reflection efficiency of the infrared ray L2 to the measuring device 50 can be improved compared to, for example, a configuration in which a reflecting material is not formed on the reflecting surface 16.

[0036] B. Second Embodiment: Figure 5 shows the configuration of a reflex reflector 10a in this second embodiment as viewed from the side. Of the configuration of the reflex reflector 10a of the second embodiment, the same components as those of the reflex reflector 10 of the first embodiment described above are designated by the same reference numerals and their description will be omitted. The reflex reflector 10a has an infrared-transmitting portion 12a and a reflective portion 14a.

[0037] The reflecting portion 14a is a light-transmitting member. The light-transmitting member may be formed from a material (e.g., glass, acrylic resin, etc.) that is transmissive to not only infrared rays but also visible light. The front surface 19a of the reflecting portion 14a is flat, and the back surface 15a of the reflecting portion 14a is formed in a cube-corner shape. The reflecting portion 14a has a reflecting surface 16 (the same as in FIG. 3 ) that internally reflects the infrared rays L1 that have passed through the infrared-transmitting portion 12a. Note that a reflective material may be formed on the reflecting surface 16 of the reflecting portion 14a by metal vapor deposition or the like.

[0038] The infrared transmitting portion 12a is made of an infrared transmitting material. The infrared transmitting portion 12a is a plate-shaped member and is arranged along the front surface of the reflecting portion 14a. The infrared transmitting portion 12a constitutes the front surface 13a of the reflex reflector 10a. The color of the infrared transmitting portion 12a as a whole is a visible light absorbing color.

[0039] According to the second embodiment, similarly to the first embodiment, it is possible to reduce the visibility of the reflex reflector 10a to the human eye while efficiently reflecting the infrared rays L1 from the measuring device 50. Furthermore, in the second embodiment, the number of portions that need to be made of an infrared-transmitting material is reduced compared to the first embodiment, thereby reducing manufacturing costs.

[0040] C. Third Embodiment: Figure 6 shows the configuration of a reflex reflector 10b in this third embodiment as viewed from the side. Of the configuration of the reflex reflector 10b in the third embodiment, the same components as those in the reflex reflector 10 in the first embodiment described above are designated by the same reference numerals and their description will be omitted. The reflex reflector 10b has an infrared-transmitting portion 12b, a reflective portion 14b, and a reflective material 17b.

[0041] The infrared transmitting portion 12b is made of an infrared transmitting material that transmits infrared rays and blocks visible light. The infrared transmitting portion 12b is a plate-shaped member. The infrared transmitting portion 12b constitutes the front surface 13b of the reflex reflector 10b. The color of the infrared transmitting portion 12b as a whole is a visible light absorbing color.

[0042] The reflecting portion 14b is a flat plate-shaped member having a diffusing texture, such as a wrinkled pattern (texture) added to the surface of a metal or the like. The reflecting portion 14b is disposed along the back surface of the infrared transmitting portion 12b. The reflecting material 17b is formed on the surface of the reflecting portion 14b by metal vapor deposition or the like.

[0043] According to the third embodiment, similarly to the first embodiment, it is possible to reduce the visibility of the reflex reflector 10b to the human eye while efficiently reflecting the infrared rays L1 from the measuring device 50. Furthermore, in the third embodiment, unlike the first embodiment, the reflecting portion 14b does not have a cube corner, and therefore it is possible to reduce the thickness of the reflex reflector 10b.

[0044] D. Fourth Embodiment: Fig. 7 is an explanatory diagram showing an example of mounting a reflex reflector in a fourth embodiment. The mounting example in Fig. 7 differs from the mounting example in Fig. 2 in that a long lamp 30 and a pair of rear combination lamps 20E, 20E are mounted instead of the pair of rear combination lamps 20B, 20B.

[0045] One rear combination lamp 20E is disposed on the lower right side of the rear window 25, and the other rear combination lamp 20E is disposed on the lower left side of the rear window 25. Each rear combination lamp 20E has a reflex reflector 10E and a rear lamp 22E. Each rear lamp 22E has a light source (e.g., an LED or an incandescent lamp).

[0046] Each reflex reflector 10E is disposed within the light-emitting surface of the rear lamp 22E. Each reflex reflector 10E has the same configuration as any one of the reflex reflectors 10 (10A to 10D), 10a, and 10b of the above-described embodiments.

[0047] The long lamp 30 is disposed between the pair of rear combination lamps 20E in the left-right direction. The long lamp 30 has a rod-like shape extending in the left-right direction and includes a light source (e.g., an LED). The long lamp 30 may be a line lamp.

[0048] A pair of rear combination lamps is located at both the left and right ends of the rear end of a vehicle. Therefore, a measuring device can identify the presence of a vehicle traveling ahead and the vehicle's width by recognizing the pair of rear combination lamps (the light-emitting points of the pair of rear lamps and the reflecting points of the pair of reflectors). However, in recent years, to improve vehicle design, long lamps have been installed at the rear end of vehicles and are often turned on constantly, both day and night. Therefore, the light emitted by the long lamps may make it difficult for the measuring device to recognize the pair of rear combination lamps.

[0049] In contrast, in this embodiment, the pair of rear combination lamps 20E, 20E are each provided with a reflex reflector 10E, so that the measuring device 50 can accurately recognize the pair of rear combination lamps 20E, 20E of the nearby vehicle M2 by emitting infrared rays.

[0050] E. Fifth embodiment: Fig. 8 is an explanatory diagram showing an example of mounting a reflex reflector in a fifth embodiment. The mounting example in Fig. 8 differs from the mounting example in Fig. 2 in that a long lamp 32 is mounted.

[0051] The long lamp 32 has a rod-like shape extending in the left-right direction and includes a light source (e.g., an LED). Both left-right ends of the long lamp 32 are located outside the pair of fourth reflex reflectors 10D in the left-right direction. The pair of fourth reflex reflectors 10D are disposed within the light-emitting surface of the long lamp 32.

[0052] According to this embodiment, the fourth reflex reflectors 10D are disposed at both left and right ends of the elongated lamp 32. Therefore, the measuring device 50 can accurately recognize the pair of fourth reflex reflectors 10D on the surrounding vehicle M2 by emitting infrared rays.

[0053] F. Modifications: The technology disclosed in this specification is not limited to the above-described embodiment, and can be modified in various forms without departing from the spirit of the invention. For example, the following modifications are also possible.

[0054] In the above embodiments, LiDAR has been used as an example of the measurement device, but this is not a limitation and optical measurement devices other than LiDAR may also be used. In the first embodiment, the lighting device was the rear combination lamp 20B or the tail lamp device 20C, but this is not a limitation and may be a headlamp device or the like. In the first embodiment, the lamp was the tail lamp 22C or the like, but this is not a limitation and may be a headlamp or the like.

[0055] In the above embodiments, the infrared reflective structure is a reflex reflector mounted on a vehicle, but the present invention is not limited to this and may be a reflector mounted on a moving object other than a vehicle (e.g., a bicycle), a reflector disposed on a fixed object (e.g., a traffic sign), or a reflector disposed on a helmet, safety clothing, etc. By applying the present invention to such a reflector, it is possible to improve the detection accuracy using infrared light while suppressing the impact on the design of the object to which the present invention is applied.

[0056] In the first embodiment, the reflex reflector 10 may not have the reflecting material 17 .

[0057] The reflective portions 14, 14a in the first and second embodiments may have a retroreflective structure other than a cube-corner structure (e.g., a glass bead structure). In the first and second embodiments, the reflective portions 14, 14a have a retroreflective structure that retroreflects the infrared rays L1 transmitted through the infrared-transmitting portions 12, 12a. However, the present invention is not limited to this, and the reflective portions 14b may have a structure that diffusely reflects or specularly reflects the infrared rays L1. In the third embodiment, the reflective portions 14b are not limited to a diffuse texture, and may have a retroreflective structure, for example.

[0058] The lighting device in the fourth embodiment may be configured to include a pair of rear combination lamps 20B, 20B, without including the long lamp 30. Each reflex reflector 10E may be disposed around the light-emitting surface of the rear lamp 22E. The long lamps 30, 32 are not limited to being linear, but may also be curved.

[0059] The elongated lamp 32 in the fifth embodiment may be mounted on a location other than the rear end of the vehicle (for example, on the side or front end of the vehicle). The pair of fourth reflex reflectors 10D may be arranged around the light-emitting surface of the elongated lamp 32. Moreover, the fourth reflex reflector 10D may be arranged in the central portion of the elongated lamp 32.

[0060] This international application claims priority based on Japanese Patent Application No. 2024-111370, filed on July 11, 2024, and Japanese Patent Application No. 2025-108308, filed on June 26, 2025. The entire contents of Japanese Patent Application Nos. 2024-111370 and 2025-108308 are incorporated by reference into this international application.

[0061] The above descriptions of specific embodiments of the present invention have been presented for purposes of illustration. They are not intended to be exhaustive or to limit the invention to the precise forms described. Numerous modifications and variations will be apparent to those skilled in the art in light of the above description.

[0062] 10 (10A to 10D), 10a, 10b, 10E: Reflex reflector 12, 12a, 12b: Infrared transmitting portion 14, 14a, 14b: Reflecting portion 16, 17, 17b: Reflecting material 20B: Rear combination lamp 20C: Tail lamp device 22B: Back lamp 22C: Tail lamp 30, 32: Long lamp 50: Measuring device L: Infrared M1: Vehicle M2, M3: Surrounding vehicles

Claims

1. An infrared reflective structure comprising: an infrared-transmitting portion that transmits infrared rays and absorbs visible light; and a reflecting portion that is disposed on the back side of the infrared-transmitting portion and reflects the infrared rays that have transmitted through the infrared-transmitting portion.

2. An infrared reflective structure according to claim 1, wherein the reflecting portion has a retroreflective structure that retroreflects infrared light that has passed through the infrared transmitting portion.

3. An infrared reflective structure according to claim 1 or 2, wherein the reflecting portion has a reflecting surface that internally reflects the infrared light that has passed through the infrared transmitting portion, and a reflecting material having a higher light reflectance than the reflecting surface is formed on the reflecting surface.

4. An infrared reflective structure according to claim 1 or 2, wherein the reflecting portion is a light-transmitting member having a reflective surface that internally reflects infrared light that has passed through the infrared-transmitting portion, and the infrared-transmitting portion is a plate-like member that is arranged along the front surface of the reflecting portion.

5. A lighting device comprising: a lamp; and an infrared reflective structure according to claim 1 or 2.

6. A lighting device according to claim 5, wherein the lamp is a rear lamp mounted on the rear of a vehicle, and the infrared reflective structure is provided on the rear lamp.

7. An illumination device according to claim 5, wherein the lamp is an elongated lamp extending in a predetermined direction, and the infrared reflective structure is provided on the elongated lamp.

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