Lamp unit

Abstract

To provide a lamp device which can effectively suppress multiple reflection by the reflected radar waves reflected by a part constituting a vehicle body and returning to the inside of a lamp body, and has a highly accurate radar function.SOLUTION: A lamp device includes: a housing 11 which is a mounting part on a vehicle; a lamp unit 14; a radar unit 15 having an antenna 15X transmitting a radar wave and receiving a reflected wave from an object; a translucent cover 12 which is mounted covering the front side of a housing so as to house the lamp unit and the radar unit in the inside and transmits the radar wave therethrough; and a radio wave absorbing part 20 which is provided on the surface opposite to the translucent cover of the housing or on the surface opposite thereto.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a lamp device, and more particularly to a lamp device for a vehicle incorporating a radar device. [Background technology]

[0002] For driving assistance and autonomous driving, various sensors are used, such as acceleration sensors, GPS sensors, cameras, LiDAR (Light Detection and Ranging), and millimeter wave sensors.

[0003] In particular, millimeter wave radar maintains high environmental resistance, not being affected by nighttime or backlit environments, or bad weather such as thick fog, rain, and snow. It can also directly detect the distance and direction to an object, as well as the relative speed to the object. Therefore, it has the characteristic of being able to detect objects at close range with high speed and high accuracy.

[0004] Patent Document 1 discloses a vehicle lamp having a millimeter wave radar mounted in a lamp chamber, and a light guide member that transmits millimeter waves provided between a front cover and the millimeter wave radar.

[0005] Patent Document 2 discloses a vehicle lamp equipped with a light source unit and a millimeter wave radar, with a resin cover that is visible on the exterior of the vehicle body, with an opaque design portion provided in part of the resin cover, which shields the millimeter wave radar.

[0006] Furthermore, Patent Document 3 discloses an in-vehicle light device having a separator arranged to separate the space between the lighting unit and the radar unit, blocking the transmission of radiant heat and electromagnetic waves between the lighting unit and the radar unit. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Patent No. 4842161 [Patent Document 2] Patent No. 5130192 [Patent Document 3] JP 2020-51974 A Summary of the Invention [Problem to be solved by the invention]

[0008] However, if radar waves are reflected by components placed on the front of the radar unit, such as a front cover or extension, and the reflected waves and multiple reflected waves cause ghosts (obstacles that do not actually exist), this will reduce the detection function of the radar device.

[0009] The present invention has been made in consideration of the above-mentioned points, and aims to provide a lamp device that has high-precision radar function, such as being able to effectively suppress radar wave reflection and multiple reflection, having low noise, and a wide dynamic range.

[0010] Another object of the present invention is to provide a lamp device having a highly accurate radar function, which can effectively suppress multiple reflections caused by radar waves reflected by parts constituting the vehicle body and returning to the inside of the lamp body. [Means for solving the problem]

[0011] A lamp device according to one embodiment of the present invention comprises: A housing which is an attachment part to a vehicle; A lamp unit; Radar waves As a transmission wave Send, The transmission wave a radar unit having an antenna for receiving a reflected wave from an object; a light-transmitting cover attached to cover a front side of the housing so as to house the lamp unit and the radar unit therein, the light-transmitting cover transmitting the radar wave; a radio wave absorbing portion provided on a surface of the housing facing the light-transmitting cover or on a surface opposite the surface; connected to the radar unit A signal processing unit; Including, The signal processing unit includes an object intensity / distance calculation unit and an unwanted reflection intensity / distance calculation unit, the object intensity / distance calculation unit calculates a relationship between a time difference between the transmitted wave and the reflected wave and a signal intensity of the reflected wave, the unwanted reflection intensity / distance calculation unit calculates a relationship between a time difference between the transmission wave and an unwanted reflection wave that reaches the antenna after being attenuated by the radio wave absorbing unit having a predetermined radio wave absorption rate, and a signal intensity of the unwanted reflection wave, The signal processing unit processes the signal based on the reflected wave and the unwanted reflected wave received by the antenna in the object intensity / distance calculation unit and the unwanted reflection intensity / distance calculation unit, thereby calculating the distance from the object to the radar unit. .

[0012] A lamp device according to another embodiment of the present invention comprises: A housing which is an attachment part to a vehicle; A lamp unit; Radar waves As a transmission wave Send, The transmission wave a radar unit having an antenna for receiving a reflected wave from an object; a light-transmitting cover attached to cover a front side of the housing so as to house the lamp unit and the radar unit therein, the light-transmitting cover transmitting the radar wave; connected to the radar unit A signal processing unit; Including, The signal processing unit includes an object intensity / distance calculation unit and an unwanted reflection intensity / distance calculation unit, the object intensity / distance calculation unit calculates a relationship between a time difference between the transmitted wave and the reflected wave and a signal intensity of the reflected wave, the unwanted reflection intensity / distance calculation unit calculates a relationship between a time difference between the transmission wave and an unwanted reflected wave that reaches the antenna after being attenuated by the housing having a predetermined radio wave absorption rate, and a signal intensity of the unwanted reflected wave, the signal processing unit calculates a distance from the object to the radar unit by processing a signal based on the reflected wave and the unwanted reflected wave received by the antenna in the object intensity / distance calculation unit and the unwanted reflection intensity / distance calculation unit, The housing contains an electromagnetic wave absorbing material that absorbs the radar waves. [Brief description of the drawings]

[0013] [Figure 1] 1 is a diagram illustrating an example of an internal structure of a lamp device according to a first embodiment of the present invention. [Figure 2A] FIG. 2 is a diagram showing a schematic configuration and arrangement of a radar unit 15. [Figure 2B] 2 is a block diagram showing an example of the configuration of a millimeter wave sensor module 30 provided in a radar unit 15. FIG. [Diagram 3] 10 is a flowchart showing a procedure for identifying an object executed by the millimeter wave sensor module 30. [Figure 4] 1 is a time chart showing the relationship between the time difference (Δt) between a transmitted wave TX and a reflected wave RX in a pulse radar system. [Diagram 5]1 is a graph showing the principle of object identification by the millimeter wave sensor module 30. [Figure 6] 3A to 3C are diagrams illustrating reflection from vehicle body components in the lamp device 10 of the first embodiment. [Figure 7A] FIG. 11 is a diagram illustrating an example of the internal structure of a lamp device 40 according to a second embodiment of the present invention. [Figure 7B] 10 is a diagram illustrating the arrangement and size of a radio wave absorber 20 in a second embodiment of the present invention. FIG. [Figure 8] FIG. 11 is a diagram illustrating an example of the internal structure of a lamp device 50 according to a third embodiment of the present invention. [Figure 9] FIG. 11 is a diagram illustrating an example of the internal structure of a lamp device 60 according to a fourth embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] In the following, preferred embodiments of the present invention will be described, but these may be modified or combined as appropriate. In the following description and accompanying drawings, substantially the same or equivalent parts are designated by the same reference numerals. [First embodiment] 1 is a diagram showing an example of the internal structure of a lamp device 10 according to a first embodiment of the present invention. The lamp device 10 is mounted on a vehicle such as an automobile. For example, the lamp device is a headlight, but it can also be used as a lamp device such as a taillight.

[0015] In the following description, an automobile will be taken as an example of a vehicle, but the present invention is not limited thereto. That is, in this specification, a vehicle refers to a vehicle such as a ship or an aircraft, and manned or unmanned transportation means.

[0016] FIG. 1 shows a schematic cross section in a horizontal plane (or a plane parallel to the road surface) when a lamp device 10 (left headlamp) mounted on the left front of a vehicle is viewed from above.

[0017] In the lamp device 10, a lamp housing (casing) 13 is formed by a base (housing) 11 and a light-transmitting cover (front cover) 12 attached to the front side or forward side of the base 11.

[0018] That is, the light-transmitting cover 12 is attached to the base 11 so as to cover the front side of the base 11, and the base 11 is attached to the vehicle body, whereby the lamp device 10 is mounted on the vehicle body (not shown). The light-transmitting cover 12 includes those having light transmissivity that transmits light of a color other than white, such as red or yellow.

[0019] The base 11 is made of plastic (resin). For example, the headlight is made of PP (polypropylene), and the taillight is made of ASA (acrylonitrile styrene acrylic rubber), but is not limited to these. Metal may also be used partially.

[0020] The light-transmitting cover 12 is made of a light-transmitting resin such as polycarbonate (PC) or acrylic (PMMA).

[0021] Built into the lamp housing 13 are a headlamp unit 14 which is a lamp unit (light source), a millimeter wave radar unit (hereinafter simply referred to as the radar unit) 15 which is a radar device, a light emitting unit 16, and an extension 19. The base 11 is disposed on a surface excluding a transmitting / receiving surface (an antenna surface 15S described below) of the radar unit 15, for example, on the rear side as viewed from the radar unit 15.

[0022] In this embodiment, a radio wave absorber 20 is provided on the base 11 as a radio wave absorbing section that absorbs radar waves. More specifically, the radio wave absorber 20 is provided at a position where it absorbs radar waves reflected by a member, particularly the translucent cover 12, that is provided in front of the radar unit in the lamp device 10 and directed toward a vehicle component, and radar waves reflected by the vehicle component and directed toward the inside of the lamp device 10. That is, the reflected radar waves are absorbed by the radio wave absorber 20 on both the round trip. Note that, although the radio wave absorber 20 is provided on the inside of the base 11 in FIG. 1, that is, on the side facing the translucent cover 12, it may be provided on the outside, that is, on the opposite side to the translucent cover 12.

[0023] The vehicle components in question are radar wave reflecting parts, for example vehicle parts made of metal, such as the engine, chassis, radiator, etc.

[0024] In this specification, the lamp device 10 is not limited to a headlight light source, but refers to a light-emitting device having the purpose and function of emitting light to the outside, such as a tail lamp or backlight.

[0025] The headlamp unit 14 has a light source such as an LED (Light Emitting Diode) and a lens or reflector for distributing and irradiating the light from the light source. The headlamp unit 14 is disposed along an optical axis AX1 and is provided so as to irradiate low beam (passing beam) and high beam (driving beam) light LB in the forward direction (FRONT in the drawing).

[0026] The radar unit 15 has a transmitting / receiving surface 15S on the front of which a millimeter wave transmitting / receiving antenna 15X is provided. In this specification, the transmitting / receiving surface of the radar unit (radar device) 15 (the front surface of the radar unit 15) is also referred to as the antenna surface 15S.

[0027] The radar unit 15 transmits millimeter waves from the transmitting / receiving antenna 15X and receives the waves reflected by an object.

[0028] The received signal is processed by a control device, for example, a signal processing device, and the distance, speed, and angle to the target are detected. In the radar unit 15, for example, millimeter waves in the 76-81 GHz band, particularly millimeter waves in the 79 GHz band, are preferably used, but are not limited to this frequency band.

[0029] The light-emitting unit 16 has a light source 16A and a light guide 16B that is composed of at least one light guide member that guides the light from the light source 16A. The light-emitting unit 16 functions as a DRL (Daytime Running Lights) or a turn lamp. The light source 16A has, for example, an LED or an incandescent bulb, and supplies the light to the light guide 16B.

[0030] The normal direction AX2 of the antenna surface 15S of the radar unit 15 is arranged so as to be inclined at an angle θ (45° in this embodiment) outward (i.e., leftward in the case of the left headlight) with respect to the optical axis AX1 of the headlight unit 14 (or with respect to the direction of travel of the vehicle).

[0031] Further, an extension 19 is provided inside the lamp housing 13. The extension 19 is a design part provided to reflect or guide light, or to make the internal structure difficult to see from the outside.

[0032] It should be noted that the light emitting unit 16 and the extension 19 do not necessarily have to be provided.

[0033] In this embodiment, the radar wave (transmission wave TX) from the radar unit 15 is directly irradiated to the outside through the light-transmitting cover 12.

[0034] A shielding member may be provided in front of the radar unit 15 to make the radar unit 15 difficult to see from the outside.

[0035] 2A is a diagram showing a schematic configuration and arrangement of the radar unit 15. The radar unit 15 has a transmitting antenna (TX antenna) 15TX, a receiving antenna (RX antenna) 15RX, and a millimeter wave sensor device (hereinafter also referred to as a millimeter wave sensor module) 30. Note that the transmitting antenna 15TX and the receiving antenna 15RX may be configured as a common antenna 15X depending on the radar system. Hereinafter, when there is no particular distinction between the transmitting antenna and the receiving antenna, they will be described as the transmitting / receiving antenna 15X.

[0036] FIG. 2B is a block diagram showing an example of the configuration of the millimeter wave sensor module 30 provided in the radar unit 15.

[0037] The millimeter wave sensor module 30 detects an object (target) by, for example, a pulse radar system or an FMCW (frequency modulated continuous wave) system. More specifically, a generator (synthesizer system) 31 generates a transmission wave. In the case of the pulse radar system, a repeating pulse wave is generated as the transmission wave, and in the case of the FMCW system, a modulated wave is generated as the transmission wave.

[0038] A transmission wave (TX wave) generated by a generator 31 is transmitted by a transmitter 32 from a transmission antenna 15TX as a transmission wave.

[0039] The reflected wave (RX wave) reflected by the object is received by the receiving antenna 15RX. The transmitted wave and the received reflected wave (received wave) are processed by the signal processor 35, and the distance, speed, and angle of the object are detected.

[0040] The signal processing unit 35 has an object distance / intensity calculation unit 35A that calculates the signal strength (received signal strength) VR of the received wave and the distance (or delay time Δt) of the object to be detected, and a signal identification unit 35B that identifies the signal from the object based on the calculated signal strength and distance.

[0041] The signal discriminating unit 35B has a relational expression that expresses the correspondence between the signal strength VR from an object that is to be correctly detected and the distance (time difference Δt).

[0042] The signal discrimination unit 35B discriminates between a signal from an object to be detected and a ghost or noise due to reflection (unwanted reflected waves) based on the correspondence and the radio wave absorption rate or the signal intensity attenuation rate of the radio wave absorber 20. That is, the signal discrimination unit 35B functions as an unwanted signal discrimination unit.

[0043] More specifically, for example, the signal identification unit 35B has an unwanted reflection distance / intensity calculation unit that calculates the relationship between the delay time (time difference) from the time of transmission of the radar wave of the unwanted reflected wave that is attenuated by the radio wave absorber 20 and reaches the antenna 15X, and the signal strength of the unwanted reflected wave.

[0044] In the case of the FMCW system, a mixer that mixes a transmission wave (modulated wave) and a reception wave to generate an IF (intermediate frequency) signal, an AD converter (analog-to-digital converter: ADC), and the like are provided.

[0045] Millimeter Wave Sensor Module The radar signal strength detector 30 is configured to detect the distance (or delay time) of an object and the signal strength of the radar wave, and to identify whether or not the signal is from an object (target object).

[0046] Fig. 3 is a flowchart showing the procedure of object identification executed by the millimeter wave sensor module 30. Fig. 4 is a time chart showing the relationship of the time difference (Δt) between the transmitted wave TX and the reflected wave RX in the pulse radar system.

[0047] Fig. 5 is a graph showing the principle of object identification by the millimeter wave sensor module 30. Fig. 6 is a diagram for explaining reflection from vehicle body components in the lamp device 10 of the present embodiment.

[0048] The flow of object identification will be described with reference to Fig. 3. First, the millimeter wave sensor module 30 transmits a transmission wave TX generated by the generator 31 from the transmission antenna 15TX (step S11). Next, a reflected wave RX reflected by an object is received by the reception antenna 15RX (step S12).

[0049] Next, the signal processing unit 35 calculates the intensity VR of the reflected wave RX and the time difference (Δt) between the transmitted wave TX and the reflected wave RX (step S13). The time difference (Δt) is equivalent to the distance to the object that reflected the transmitted wave TX.

[0050] Here, referring to FIG. 4, the reflected wave RX reflected by an object is received with a time difference (Δt) from the time (time T=0) when the transmitted wave TX (intensity VX) is transmitted.

[0051] For example, the time difference (Δt1) of the reflected wave RX from an object (detection target PF) that is relatively far from the radar unit 15 is larger than the time difference (Δt2) of the reflected wave RX from an object (detection target PN) that is relatively close (Δt1>Δt2).

[0052] In addition, regarding the signal strength VR of the reflected wave RX, the signal strength (V1) of the reflected wave RX from an object (detection target PF) that is relatively far away is smaller than the signal strength (V2) of the reflected wave RX from an object (detection target PN) that is relatively close (V1 <V2)。

[0053] On the other hand, as shown in FIG. 6, inside the lamp device 10, there are reflected radar waves (hereinafter simply referred to as reflected waves) RW that are reflected or multiply reflected by internal components of the device such as the translucent cover 12, which is the front cover, the headlamp unit 14, and the extension 19.

[0054] According to the lamp device 10 of this embodiment, of the reflected waves RW, the reflected waves RP traveling from inside the lamp device 10 toward the vehicle component 90, and the vehicle reflected waves RQ reflected by the vehicle component 90 and traveling toward the inside of the lamp device 10 are absorbed by the radio wave absorber 20, and their intensity is greatly reduced.

[0055] Therefore, even though the reflected wave from the vehicle component 90 (vehicle internal reflected wave) is in a short distance (Δt is small), its signal strength is smaller than that of the reflected wave from the object to be detected (close-distance object PN) outside the lamp device 10 by the amount of absorption by the radio wave absorber 20. For example, as shown in FIG. 4, even if the time difference (Δt2) is the same as that of the close-distance object PN, the signal strength is smaller than that of the close-distance object PN (V3 <V2)。

[0056] 3 and 5, the signal processing unit 35 has a reference function (VR-Δt function) that expresses the correspondence relationship between the signal strength VR and the distance (time difference Δt) from an object that is to be detected correctly. The signal discrimination unit 35B discriminates between the object to be detected and ghosts or noises due to unnecessary reflections based on the correspondence relationship and the signal strength attenuation rate due to the radio wave absorber 20 (step S14).

[0057] More specifically, for example, a threshold function (Vth-Δt) obtained by subtracting the amount of signal strength attenuation caused by the radio wave absorber 20 from the reference function (VR-Δt) is used as a reference, and a signal equal to or greater than the threshold is output as a detection signal for an object (step S15 ).

[0058] On the other hand, signals below the threshold (signals within the hatched area in FIG. 5) are deemed to be ghosts or noise (unwanted reflected waves) and are excluded from the detection target (step S15 "NO" in

[0059] Alternatively, the signal processing unit 35 may hold a threshold function (Vth-Δt) and directly use the threshold function to distinguish between an object to be detected and a ghost or noise due to reflection. The above-mentioned reference function or threshold function or an equivalent relational expression may be held, for example, as a mathematical expression or a table.

[0060] Although the pulse radar system has been described above as an example, the present invention can be similarly applied to other radar systems such as the FMCW (frequency modulated continuous wave) system.

[0061] As the radio wave absorber 20, for example, a carbon sheet or a resin containing a radio wave absorbing material such as carbon (carbon powder, carbon nanotubes, or carbon fibers) or ferrite can be used. For example, a carbon sheet having a radar wave transmittance of about 40% (i.e., attenuation rate of 60%) can be used as the radio wave absorber 20. Alternatively, the transmittance of polycarbonate (PC) is about 20%, and a carbon-containing PC having a transmittance of about 20% (i.e., attenuation rate of 80%) can be used as the radio wave absorber 20. Furthermore, it is more preferable to use a carbon sheet or a carbon-containing PC having a radar wave transmittance of 10% or less (i.e., attenuation rate of 90% or more) as the radio wave absorber 20.

[0062] If the translucent cover 12 does not have an optimized thickness for the frequency of the radar wave, a large reflected wave (for example, about -5 dB) will be generated. The radar wave reflected from the translucent cover 12 returns in the direction of the base 11 as a reflected wave. To sufficiently absorb this, it is preferable that the radio wave absorber 20 has an attenuation rate that is at least twice the reflection attenuation rate (radio wave reflectance rate) of the translucent cover 12, which is the front cover. In this case, the radar wave reflected by the translucent cover 12 is reflected by the vehicle components, and the intensity of the reflected wave returning to the radar unit 15 is reduced to about 1 / 10 or less, thereby achieving sufficiently high noise identification accuracy.

[0063] The radio wave absorber 20 is not limited to the above-mentioned examples, and various materials such as dielectric radio wave absorbing materials, magnetic radio wave absorbing materials, conductive radio wave absorbing materials, or combinations of these materials can be used.

[0064] Furthermore, if the radar waves reflected by the radio wave absorber 20 are sufficiently absorbed and the target object can be detected with sufficient accuracy, the process of identifying unnecessary signals using a threshold function (Vth-Δt) (step S14) may not be necessary.

[0065] According to the lamp device of this embodiment, the radar waves reflected by components inside the lamp device, such as the light-transmitting cover (front cover) 12, are reflected by vehicle components such as the engine, and the reflected waves return to the lamp device. This makes it possible to effectively suppress ghosts or noise caused by undesired reflected radar waves (and their multiple reflected waves). Furthermore, the base 11 is disposed on the surface of the radar unit 15 excluding the antenna surface 15S, and the radio wave absorber 20 is disposed on the base 11, so that undesired reflected radar waves (and their multiple reflected waves) from components disposed on the front portion of the radar unit 15 can be efficiently absorbed.

[0066] Therefore, it is possible to provide a lamp device having a highly accurate radar function with low noise, a wide dynamic range, etc. Also, it is easy to distinguish between signals and noise, and a high-speed and highly accurate radar function can be realized.

[0067] In particular, in a cross traffic radar used for a cross traffic alert that detects objects diagonally in front of or behind a vehicle, the radar detects objects at a relatively short distance, making it difficult to distinguish between ghosts or noise (unwanted reflected waves) caused by reflections from vehicle components. According to the present invention, it is possible to distinguish between object detection signals and unwanted reflected waves with high accuracy, particularly when detecting objects at a relatively short distance. [Second embodiment] FIG. 7A is a diagram showing an example of the internal structure of a lamp device 40 according to the second embodiment of the present invention, and FIG. 7B is a diagram explaining the arrangement and size of a radio wave absorber 20. As shown in FIG.

[0068] In this embodiment, the radio wave absorber 20 may be provided on a part of the base 11. The radio wave absorber 20 (radio wave absorbing portion) is provided so as to be disposed between the radar unit 15 and the vehicle component 90, i.e., on a part of the base 11 that separates the radar unit 15 and the vehicle component 90, when the radio wave absorber 20 is attached to the vehicle.

[0069] More specifically, the radio wave absorber 20 is configured such that at least the reflected wave from the light-transmitting cover 12 is reflected by the vehicle component 90, and the reflected wave from the lamp device 40 The reflector 1 is provided at a position and with a size that attenuates the reflected wave RQ toward the inside of the reflector 1.

[0070] In other words, the radio wave absorber 20 is provided in at least a part of the area on the surface of the base 11 facing the light-transmitting cover (front cover) 12. That is, the radio wave absorber 20 is provided in at least a part of the area on the rear surface of the lamp device 40. The radio wave absorber 20 may be provided on either the inner side or the outer side of the lamp device 40.

[0071] Fig. 7B is a schematic partial enlarged view for explaining the arrangement of the radio wave absorber 20. As shown in Fig. 7B, the radio wave absorber 20 (radio wave absorbing portion) is preferably provided to have an area PR that is larger than an area R1 on the base 11 when the radar unit 15 is projected onto the base 11 along a normal direction AX2 of the transmission surface and / or reception surface (antenna surface 15S) of the antenna 15X of the radar unit 15, and has a position and size that includes the projection area R1.

[0072] Alternatively, it is preferable that at least the radio wave absorber 20 is provided at a position and with a size (area PR of the radio wave absorber 20) that is larger than the area R2 on the base 11 when the antenna 15X is projected onto the base 11 along the normal direction AX2 and that includes the projected area R2.

[0073] The lamp device 40 of the second embodiment can prevent the radar waves reflected from the vehicle parts such as the engine from being incident on the antenna 15X and generating noise or affecting the transmission waves from the antenna 15X. In addition, it can prevent the radar waves reflected from the vehicle parts that are incident on the radar unit 15 from being multiple-reflected within the radar unit 15 and impairing the radar function of the radar unit 15.

[0074] According to the lamp device of this embodiment, radar waves reflected by a translucent cover or the like are reflected by vehicle components and return to the inside of the lamp device, and ghosts or noise caused by these multiple reflected waves can be effectively suppressed.

[0075] Therefore, it is possible to provide a lamp device having a highly accurate radar function with low noise, a wide dynamic range, etc. Also, it is easy to distinguish between signals and noise, and a high-speed and highly accurate radar function can be realized. [Third embodiment] FIG. 8 is a diagram illustrating an example of the internal structure of a lamp device 50 according to the third embodiment of the present invention.

[0076] A lamp device 50 of this embodiment differs from the lamp device 10 of the first embodiment in that a base 11A is made of a radio wave absorbing resin containing a radio wave absorbing material such as carbon, instead of the base 11 of the lamp device 10 of the first embodiment.

[0077] More specifically, the base 11A is made of a carbon-containing resin, for example, polycarbonate (PC) containing carbon. For example, a carbon-containing resin having a radar wave transmittance of 40% or less is preferably used as the base 11A, and a carbon-containing resin having a radar wave transmittance of 10% or less is more preferably used.

[0078] The entire base 11A is not limited to being made of a resin containing a radio wave absorbing material. As described above, it is sufficient that the radio wave absorbing material is contained in the resin of the base 11 and a radio wave absorbing material-containing region (radio wave absorbing portion) is provided so as to have a region PR whose position and size include at least the region R1 on the base 11 when the radar unit 15 or the antenna 15X is projected on the base 11 in the normal direction AX2 of the antenna surface 15S.

[0079] According to the lamp device 50 of this embodiment, the radio wave absorbing portion is attached to the base body with a simple structure. 11A It is possible to provide a lamp device having a radar function that has the same advantages as the above-described embodiment.

[0080] In this embodiment, a shielding member (extension) 18 is provided between the radar unit 15 and the light-transmitting cover (front cover) 12 in front of the radar unit 15.

[0081] The shielding member 18 is provided so as to cover the front surface of the radar unit 15 in order to make the radar unit 15 difficult to see from the outside. In addition, the shielding member 18 is provided so as to cover the entire transmitting / receiving surface (antenna surface) 15S of the transmitting / receiving antenna 15X of the radar unit 15.

[0082] In addition, the radio wave absorber 20 (radio wave absorbing portion) is arranged to have an area PR whose position and size include an area R1 when the radar unit 15 is projected onto the base 11 in the normal direction AX2 of the antenna surface 15S of the radar unit 15 (see Figure 7B).

[0083] Therefore, it is possible to effectively prevent the reflected wave reflected by the shielding member 18 from being reflected by vehicle components and returning to the inside of the lamp device to cause ghosts or noise. Also, it has the same advantages as the above-mentioned embodiment. Therefore, it is possible to provide a lamp device having a high-speed and high-precision radar function with low noise and a large dynamic range. [Explanation of symbols]

[0084] 10, 40, 50, 60: Lamp unit 11: Base 12:Translucent cover 14: Lamp unit 15: Radar unit 15S: Antenna surface 15X: Transmitting and receiving antenna 16: Light emitting unit 16A:Light source 16B: Light guide 18: Shielding material 19: Extension 20: Radio wave absorption body 30: Millimeter wave sensor module 31: Generator 35: Signal processing section 35A: Distance / signal strength calculation section 35B: Signal identification section

Claims

1. A housing which is an attachment part to a vehicle; A lamp unit; a radar unit having an antenna for transmitting radar waves as transmission waves and receiving reflected waves of the transmission waves from an object; a light-transmitting cover attached to cover a front side of the housing so as to house the lamp unit and the radar unit therein, the light-transmitting cover transmitting the radar wave; a radio wave absorbing portion provided on a surface of the housing facing the light-transmitting cover or on a surface opposite the surface; a signal processor connected to the radar unit; The signal processing unit includes an object intensity / distance calculation unit and an unwanted reflection intensity / distance calculation unit, the object strength / distance calculation unit calculates a relationship between a time difference between the transmitted wave and the reflected wave and a signal strength of the reflected wave, the unwanted reflection intensity / distance calculation unit calculates a relationship between a time difference between the transmission wave and an unwanted reflected wave that reaches the antenna after being attenuated by the radio wave absorbing unit having a predetermined radio wave absorption rate, and a signal intensity of the unwanted reflected wave, The signal processing unit is a lamp device that calculates the distance from the object to the radar unit by processing signals based on the reflected waves and the unwanted reflected waves received by the antenna in the object strength / distance calculation unit and the unwanted reflection intensity / distance calculation unit.

2. The lamp device according to claim 1 , wherein the radio wave absorbing portion is provided in an area including at least an area on the housing where the radar unit is projected along a normal direction of a transmitting surface or a receiving surface of the antenna.

3. 3. The lamp device according to claim 1, wherein the radio wave absorbing portion is provided in an area including at least an area on the housing where the antenna is projected along a normal direction of a transmitting surface or a receiving surface of the antenna.

4. A housing which is an attachment part to a vehicle; A lamp unit; a radar unit having an antenna for transmitting radar waves as transmission waves and receiving reflected waves of the transmission waves from an object; a light-transmitting cover attached to cover a front side of the housing so as to house the lamp unit and the radar unit therein, the light-transmitting cover transmitting the radar wave; a signal processor connected to the radar unit; The signal processing unit includes an object intensity / distance calculation unit and an unwanted reflection intensity / distance calculation unit, the object strength / distance calculation unit calculates a relationship between a time difference between the transmitted wave and the reflected wave and a signal strength of the reflected wave, the unwanted reflection intensity / distance calculation unit calculates a relationship between a time difference between the transmission wave and an unwanted reflected wave that reaches the antenna after being attenuated by the housing having a predetermined radio wave absorption rate, and a signal intensity of the unwanted reflected wave, the signal processing unit processes a signal based on the reflected wave and the unwanted reflected wave received by the antenna in the object intensity / distance calculation unit and the unwanted reflection intensity / distance calculation unit, thereby calculating a distance from the object to the radar unit; The lamp assembly includes a radio wave absorbing material in the housing that absorbs the radar waves.

5. 5. The lamp device as described in claim 4, wherein the radio wave absorbing material-containing area of ​​the housing containing the radio wave absorbing material is provided in an area that includes at least an area on the housing onto which the radar unit is projected along a normal direction of the transmitting surface or receiving surface of the antenna.

6. 6. The lamp device according to claim 4, wherein the radio wave absorbing material-containing area of ​​the housing containing the radio wave absorbing material is provided in an area that includes at least an area on the housing where the antenna is projected along a normal direction of the transmitting surface or receiving surface of the antenna.

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