JP2019219690A - Near infrared sensor cover - Google Patents

Abstract

To improve design while securing a detection function of a near-infrared sensor.SOLUTION: A plate-like near-infrared sensor cover 20 has a plate shape, and is disposed in front of a vehicle 10 in a transmission direction of near-infrared IR1 transmitted from a near-infrared sensor 11. A main section in a thickness direction of the cover 20E for a near-infrared sensor is composed of a cover body 21, and the cover body 21 has a surface 22 on a side far from the near-infrared sensor 11 and a rear surface 23 on a side close to the near-infrared sensor 11. A reflection suppressing layer 35 is laminated on at least one of the surface 22 and the rear surface 23 of the cover body 21. Light transmittance of near-infrared of a reflection suppressing layer 35 laminated on the cover body 21 is 80% or more and light transmittance of visible light is 70% or less.SELECTED DRAWING: Figure 5

Description

  The present invention relates to a cover for a near-infrared sensor that is disposed in the forward direction of near-infrared light transmitted from a near-infrared sensor.

  In the field of vehicles, the near-infrared sensor transmits near-infrared rays toward the front of the vehicle, and receives near-infrared rays that are reflected upon a preceding obstacle including a preceding vehicle, a pedestrian, etc. A technology for detecting a relative speed has been developed (for example, see Patent Document 1).

JP 2015-209112 A

  However, if the near-infrared sensor is attached to the vehicle in a bare state, the near-infrared sensor is directly visible from the front of the vehicle. Due to this, not only the near-infrared sensor itself but also the appearance around the near-infrared sensor in the vehicle is impaired, leaving room for improvement in terms of design.

  The present invention has been made in view of such circumstances, and an object thereof is to provide a cover for a near-infrared sensor that can improve the design property while securing the detection function of the near-infrared sensor. It is in.

  A cover for a near-infrared sensor that solves the above-mentioned problem is a plate-shaped cover for a near-infrared sensor that is disposed in the vehicle in front of a transmission direction of near-infrared light transmitted from the near-infrared sensor, and a main part in a thickness direction is provided. The cover body has a surface farther from the near infrared sensor and a back surface closer to the near infrared sensor, and at least one of the front surface and the back surface of the cover body. The antireflection layer is laminated, and the near-infrared light transmittance of the laminated body of the reflection suppression layer on the cover body is 80% or more and the visible light ray transmittance is 70% or less.

  In the near-infrared sensor cover, a housing case for accommodating the near-infrared sensor is attached in a state where a wall portion thereof is close to a back surface of the cover main body, and the reflection suppressing layer includes the back surface and the wall portion. Are preferably laminated between the two.

  In the near-infrared sensor cover, it is preferable that the entire cover body is formed in a shape in which the thickness of the cover body gradually changes in a direction along the front surface and the back surface.

  In the near-infrared sensor cover, the front surface is formed of a flat surface, and a part of the back surface is inclined with respect to the front surface, so that a distance from the front surface gradually changes in a direction along the first surface. And a second plane in which the distance from the surface gradually changes in a direction along the surface by inclining the surface with respect to the surface so as to have a relationship opposite to the first plane. It is preferable that the first plane and the second plane intersect in a sharp state.

  According to the near-infrared sensor cover, it is possible to improve the design while securing the detection function of the near-infrared sensor.

FIG. 2 is a side cross-sectional view showing the near-infrared sensor cover in the first embodiment together with the near-infrared sensor. FIG. 6 is a side sectional view showing a near-infrared sensor cover according to a second embodiment together with a near-infrared sensor. FIG. 10 is a partial side sectional view of a near-infrared sensor cover according to a third embodiment. FIG. 10 is a side sectional view showing a near-infrared sensor cover according to a fourth embodiment together with a near-infrared sensor. FIG. 15 is a side sectional view showing a near-infrared sensor cover according to a fifth embodiment together with a near-infrared sensor. FIG. 14 is a side cross-sectional view showing a near-infrared sensor cover according to a sixth embodiment, together with a housing case having a reflection suppressing layer formed thereon and a near-infrared sensor. FIG. 14 is a side sectional view showing a near-infrared sensor cover according to a seventh embodiment together with a near-infrared sensor. FIG. 15 is a side sectional view showing a near-infrared sensor cover according to an eighth embodiment together with a near-infrared sensor.

(1st Embodiment)
Hereinafter, a first embodiment of a near-infrared sensor cover will be described with reference to FIG.
Near-infrared sensors 11 are attached to the front part of the vehicle 10 on both sides in the vehicle width direction. Examples of the corresponding attachment locations include both sides of the front lower grill in the vehicle width direction, both sides of the front bumper in the vehicle width direction, and the vicinity of each of a pair of fog lamps.

  Each near-infrared sensor 11 is a component that constitutes a part of the near-infrared radar device. The near-infrared sensor 11 transmits the near-infrared ray IR1 toward the front of the vehicle 10 and is reflected by a forward obstacle including a preceding vehicle, a pedestrian, and the like. By receiving the near-infrared ray IR2, the distance and the relative speed to the obstacle ahead are detected. The detection result is used for collision damage reduction control, false start suppression control, and the like. The collision damage reduction control is control for reducing damage caused by the collision by operating the brake when it is determined that there is a possibility of collision between the vehicle 10 and the obstacle ahead. The false start suppression control is a control for suppressing the output of the engine and suppressing the sudden start of the vehicle 10 when the accelerator pedal is depressed more than a certain amount in a situation where an obstacle ahead exists while the vehicle 10 is stopped. It is.

  Infrared rays are a kind of electromagnetic waves and have a wavelength longer than the wavelength of visible light (0.36 μm to 0.83 μm). The near infrared rays IR1 and IR2 have the shortest wavelength (0.83 μm to 3 μm) among infrared rays.

  As a device having a function similar to that of the near-infrared radar device, there is a millimeter-wave radar device that detects an inter-vehicle distance from a preceding vehicle traveling in front of the vehicle 10. The millimeter-wave radar device emits a millimeter wave toward a predetermined angle range in front of the vehicle 10 and detects a distance between vehicles and a relative speed with respect to a preceding vehicle from a time difference between a transmission wave and a reception wave, the intensity of the reception wave, and the like. I do.

  The near-infrared sensor 11 in each near-infrared radar device emits near-infrared rays IR1 in a wider angle range than the millimeter-wave radar device. In addition, the near-infrared sensor 11 detects a forward obstacle that is closer than the millimeter wave radar.

  In the vehicle 10, a plate-like cover for a near-infrared sensor (hereinafter, referred to as a "cover 20A") is disposed near the front in the transmission direction of the near-infrared ray IR1 transmitted from each near-infrared sensor 11, and It is attached to a strength member such as a radiator grill and a lean hosement in the vehicle 10. The cover 20A for each near-infrared sensor 11 has a common configuration.

  At least a main part in the thickness direction of each cover 20 </ b> A is constituted by the cover main body 21. In the first embodiment, the entire cover 20 </ b> A in the thickness direction is constituted by the cover main body 21. Each cover body 21 is formed of a transparent resin material, for example, a material-borne resin material mainly composed of PC (polycarbonate), PMMA (polymethyl methacrylate), COP (cycloolefin polymer), or the like. The material-attached resin material is a material in which the resin itself is colored by mixing a coloring material such as a pigment with the above resin material, or by mixing a glitter material with the resin material together with the coloring material. The entirety of each cover body 21 thus configured is colored and translucent. The light transmittance of the near infrared rays IR1 and IR2 in each cover body 21 is 80% or more, and the light transmittance of visible light is 70% or less.

  Each cover body 21 has a front surface 22 farther from the near infrared sensor 11 and a back surface 23 closer to the near infrared sensor 11. The entire cover body 21 is formed in a shape in which the thickness T, which is the distance between the front surface 22 and the back surface 23, gradually changes in the direction along the front surface 22 and the back surface 23 (in the vertical direction in FIG. 1). . In the first embodiment, the front surface 22 is formed by a flat surface, and the back surface 23 is formed by a concave curved surface. With this configuration, the thickness T of each cover main body 21 is minimized at the middle portion in the vertical direction, and gradually increases as the distance from the middle portion to the top and the bottom decreases.

Next, the operation and effects of the first embodiment configured as described above will be described.
Each cover 20 </ b> A that is colored and translucent and has a visible light ray transmittance of 70% or less is located in front of the transmission direction of the near-infrared ray IR <b> 1 transmitted from the near-infrared ray sensor 11, so that the near-infrared ray sensor 11 is provided. Demonstrate the function of hiding. In the first embodiment, this function is exerted by the cover body 21 constituting each cover 20A.

  Therefore, when each cover 20A is viewed from the front of the vehicle 10, the near-infrared sensor 11 located behind the colored translucent cover 20A (cover body 21) is difficult to see. Therefore, compared with the case where each cover 20A is not used and each near-infrared sensor 11 is attached to the vehicle 10 in a bare state, and these near-infrared sensors 11 can be directly seen, the appearance and the design are improved. Can be improved.

  In addition, in each cover body 21 which is colored and translucent, the color density varies depending on the thickness. A portion having a large thickness T is darker than a portion having a small thickness T. Therefore, the design of the cover body 21 is more varied than in the case where the thickness T of each cover body 21 is uniform and the color density is constant at any part of the cover body 21.

  Moreover, since the thickness T of each cover body 21 gradually changes in the direction along the front surface 22 and the back surface 23 of the cover body 21, the color density is continuous in the direction along the front surface 22 and the back surface 23. It changes with the gradation that was set. Therefore, the change in the shade becomes more natural than when the shade of the color changes rapidly.

  In addition, each near-infrared sensor 11 is protected by covering each near-infrared sensor 11 from the front of the vehicle 10 with each cover 20A. With this protection, each near-infrared sensor 11 is prevented from being damaged. In addition, deterioration or deterioration of each near infrared sensor 11 due to sunlight, wind, rain, temperature change, or the like is suppressed.

  When the near-infrared rays IR1 are transmitted from the near-infrared sensors 11, the near-infrared rays IR1 pass through the cover main body 21 of each cover 20A. This near-infrared ray IR1 is reflected by hitting a forward obstacle. The reflected near-infrared ray IR2 passes through the cover body 21 again, and is received by the near-infrared ray sensor 11. Since the light transmittance of the near infrared rays IR1 and IR2 in each cover body 21 is 80% or more, these cover bodies 21 are less likely to hinder transmission and reflection of the transmitted and reflected near infrared rays IR1 and IR2. Of the near infrared rays IR1 and IR2, the amount of attenuation by each cover body 21 can be kept within an allowable range. Therefore, the function of detecting the distance or the relative speed between the vehicle 10 and the obstacle ahead can be appropriately exhibited by each of the near-infrared sensors 11.

(2nd Embodiment)
Next, a second embodiment of the near-infrared sensor cover will be described with reference to FIG.
In the second embodiment, the main part of each near-infrared sensor cover (hereinafter, referred to as “cover 20B”) is configured by the cover main body 24. Each cover body 24 is made of a transparent resin material such as PC, PMMA, COP, etc., and is colorless and transparent. In this respect, the second embodiment is different from the first embodiment in which each cover body 21 is formed of a material-attached resin material and is colored and translucent.

  Each cover body 24 has a front surface 25 farther from each near infrared sensor 11 and a back surface 26 closer to the near infrared sensor 11. On the back surface 26 of each cover main body 24, a colored translucent layer 27 that is colored so that the density becomes uniform at any position along the back surface 26 is laminated. The colored translucent layer 27 is formed by printing on the back surface 26 or attaching a film to the back surface 26.

  The light transmittance of near-infrared rays IR1 and IR2 in each cover 20B formed by laminating the colored translucent layer 27 on each cover body 24 is 80% or more, and the light transmittance of visible light is 70% or less. is there.

The configuration other than the above is the same as that of the first embodiment. Therefore, the same elements as those described in the first embodiment are denoted by the same reference numerals, and redundant description will be omitted.
Therefore, according to the second embodiment, the cover main body 24 constituting the main part in the thickness direction of each cover 20B and the colored translucent layer 27 laminated on the back surface 26 have the function of hiding each near-infrared sensor 11. And makes the near-infrared sensor 11 difficult to see, so that the appearance is improved.

  Further, the cover main body 24 and the colored translucent layer 27 are unlikely to hinder the transmission of the near-infrared ray IR1 transmitted from the near-infrared ray sensor 11 and the near-infrared ray IR2 reflected on the front obstacle. Therefore, each near-infrared sensor 11 easily exerts a detection function.

  However, although the thickness T of each cover body 24 gradually changes in the direction along the front surface 25 and the back surface 26 of the cover body 24, each cover body 24 is colorless and transparent at any location. The color of each cover 20B is determined solely by the colored translucent layer 27 having a uniform density at any location. Therefore, unlike the first embodiment, it is difficult to obtain the effect of varying the color depth depending on the thickness T of each cover body 24.

(Third embodiment)
Next, a third embodiment of a cover for a near-infrared sensor will be described with reference to FIG.
In the third embodiment, the entirety of each near-infrared sensor cover (hereinafter, referred to as “cover 20C”) in the thickness direction is formed of a colored and translucent cover body 28. Each cover main body 28 is formed of a flat surface, and has a front surface 29 on the far side from each near-infrared sensor 11 and a back surface 30 on the side near the near-infrared sensor 11.

  In the third embodiment, a part of the back surface 30 has a first plane 31 inclined with respect to the front surface 29, and a second plane inclined with respect to the front surface 29 so that the first plane 31 has an opposite relationship to the first plane 31. And a plane 32. More specifically, the first plane 31 is formed so as to be inclined with respect to the surface 29 such that the distance (thickness T) between the first plane 31 and the surface 29 gradually increases toward the lower side. The second plane 32 is formed so as to be inclined with respect to the surface 29 in a direction opposite to the first plane 31 so that the distance (thickness T) between the second plane 32 and the surface 29 gradually decreases toward the lower side. I have. By the first plane 31 and the second plane 32, a projection 33 protruding rearward and having a sharp rear end is formed in a part of the cover main body 28. In other words, at the rear end of the projection 33, the first plane 31 and the second plane 32 intersect in a sharp state.

Note that the angle formed by the surface 29 of the first plane 31 may be the same as or different from the angle formed by the surface 29 of the second plane 32.
The light transmittance of the near-infrared rays IR1 and IR2 in each of the covers 20C in which a part of the back surface 30 of the cover body 28 is constituted by the first plane 31 and the second plane 32 is 80% or more, In addition, the light transmittance of visible light is 70% or less.

The configuration other than the above is the same as that of the first embodiment. Therefore, the same elements as those described in the first embodiment are denoted by the same reference numerals, and redundant description will be omitted.
Therefore, according to the third embodiment, similarly to the first embodiment, the near-infrared sensor 11 at the back of each cover main body 28 which is colored and translucent and has a visible light ray transmittance of 70% or less. Can be made harder to see and the appearance can be improved, and the design can be improved. Further, the cover main body 28 in which the light transmittance of the near-infrared rays IR1 and IR2 is 80% or more allows the near-infrared ray sensor 11 to properly exhibit the detection function.

  In addition, according to the third embodiment, a part of the visible light incident on each cover main body 28 from the front surface 29 side is reflected on the back surface 30, and the first plane 31 and the second plane 32 are separated. Differs in the mode of reflection. Therefore, when each cover 20C is viewed from the front of the vehicle 10, the first plane 31 and the second plane 32 look differently, and the design of the cover 20C is rich in change.

  In particular, a point where the first plane 31 and the second plane 32 intersect in a pointed manner (a part surrounded by a dashed-dotted frame in FIG. 3) looks like a line. Therefore, by devising the position, the extending direction, the length, and the like of this portion, the design of the cover 20C can be varied, such as expressing a lattice pattern.

(Fourth embodiment)
Next, a fourth embodiment of the near-infrared sensor cover will be described with reference to FIG.
Each near-infrared sensor cover (hereinafter simply referred to as “cover 20D”) of the fourth embodiment is laminated on the surface 22 of the colored and translucent cover main body 21 in addition to the configuration of the first embodiment, and generates heat when energized. A heating layer 34 is provided.

  As the heating layer 34, a material that hardly transmits visible light and easily transmits near infrared rays IR1 and IR2 is used. For example, a transparent conductive film made of a metal oxide-based conductive material such as ITO (indium tin oxide) or tin oxide is formed on a film-like polymer base material such as PET (polyethylene terephthalate) or PEN (polyethylene naphthalate). A film formed by sputtering or the like is used as the heating layer 34. As the heating layer 34 having such a configuration, it is desirable that the temperature distribution in the direction along the surface 22 be uniform when heat is generated.

  The light transmittance of near-infrared rays IR1 and IR2 in each cover 20D obtained by laminating the heating layer 34 on the surface 22 of the cover body 21 is 80% or more, and the light transmittance of visible light is 70% or less. is there.

The configuration other than the above is the same as that of the first embodiment. Therefore, the same elements as those described in the first embodiment are denoted by the same reference numerals, and redundant description will be omitted.
Therefore, according to the fourth embodiment, the same operation and effect as those of the first embodiment can be obtained. In addition, according to the fourth embodiment, the near-infrared ray IR1 transmitted from each of the near-infrared ray sensors 11 and the near-infrared ray IR2 reflected on a front obstacle pass through each cover 20D. At this time, the transparent heating layer 34 does not easily hinder the transmission of the near infrared rays IR1 and IR2.

  Further, at the time of snowfall, the transparent conductive film of the heating layer 34 is energized to generate heat, so that it is possible to prevent snow from adhering to the surface of each cover 20D or to melt the adhering snow.

  In particular, in the fourth embodiment, since the heating layer 34 is located at the forefront of each cover 20D, the heat generated by the heating layer 34 is easily transmitted to the snow attached to the surface of each cover 20D. Therefore, the attached snow can be efficiently melted by the heat of the heating layer 34.

(Fifth embodiment)
Next, a fifth embodiment of the near-infrared sensor cover will be described with reference to FIG.
Each of the near-infrared sensor covers (hereinafter, referred to as “cover 20E”) of the fifth embodiment has, in addition to the configuration of the first embodiment, a reflection suppressing layer formed on the back surface 23 of each cover body 21 and made of a transparent thin film. 35 is provided. Each reflection suppressing layer 35 is made of a material having a lower refractive index than the material (PC, PMMA, COP, etc.) for forming each cover body 21, for example, magnesium fluoride or the like, and is formed by vacuum deposition, sputtering, WET coating, or the like. It is formed by performing. The thickness of each reflection suppressing layer 35 is set to a size such that the near-infrared ray IR1A reflected on the back surface 23 of each cover body 21 and the near-infrared ray IR1B reflected on the back surface of the reflection suppressing layer 35 have opposite phases. ing.

  The light transmittance of near-infrared rays IR1 and IR2 in each cover 20E formed by laminating the reflection suppressing layer 35 on the back surface 23 of each cover body 21 is 80% or more, and the light transmittance of visible light is 70%. It is as follows.

The configuration other than the above is the same as that of the first embodiment. Therefore, the same elements as those described in the first embodiment are denoted by the same reference numerals, and redundant description will be omitted.
Therefore, according to the fifth embodiment, the same operation and effect as those of the first embodiment can be obtained. In addition, according to the fifth embodiment, most of the near-infrared rays IR1 transmitted from each of the near-infrared sensors 11 pass through each of the covers 20E, but some of the near-infrared rays IR1 are transmitted through the back surface 23 of each of the cover bodies 21 and the reflection suppression. Each light is reflected on the back surface of the layer 35. At this time, the near-infrared ray IR1A reflected on the back surface 23 of the cover main body 21 passes through the reflection suppressing layer 35, and a phase shift occurs between the near-infrared ray IR1B reflected on the back surface of the reflection suppressing layer 35. The near-infrared rays IR1A and the near-infrared rays IR1B have opposite phases, and the two near-infrared rays IR1A and IR1B interfere with each other and are canceled. In this way, the reflection of the near-infrared ray IR1 on the back surface side of each cover 20E is reduced. Due to the reflection, it is possible to prevent the amount of the near-infrared ray IR1 transmitted through each cover 20E from decreasing (loss). The degree of the near-infrared ray IR2 returned to the near-infrared ray sensor 11 with respect to the near-infrared ray IR1 transmitted from each of the near-infrared ray sensors 11 can be increased, so that each of the near-infrared ray sensors 11 can properly perform the detection function.

(Sixth embodiment)
Next, a sixth embodiment of the cover for a near-infrared sensor will be described with reference to FIG.
In the sixth embodiment, a housing case 36 that houses the near infrared sensor 11 is used for each near infrared sensor 11. Each storage case 36 includes a cylindrical wall portion 37, a bottom wall portion 38, and a flange wall portion 39. The cylindrical wall portion 37 has a cylindrical shape extending in the front-rear direction, and surrounds each of the near-infrared sensors 11 from up, down, left, and right. The bottom wall portion 38 is provided at the rear end of the cylindrical wall portion 37, and closes the cylindrical wall portion 37 from the rear side. The flange wall 39 is formed around the front end of the cylindrical wall 37.

A cover having the same configuration as the cover 20A in the first embodiment is used as each near-infrared sensor cover.
Each housing case 36 is attached to the vehicle 10 with the flange wall portion 39 approaching the back surface of each cover 20A (the back surface 23 of the cover body 21).

  As in the reflection suppressing layer 35 in the fifth embodiment, the reflection suppressing layer made of a transparent thin film is formed on the inner wall surface of each storage case 36 and irradiated with the near infrared rays IR1 from the respective near infrared sensors 11. A layer 41 is formed.

  The thickness of the reflection suppressing layer 41 is set to a size such that the near-infrared ray IR1 reflected on the inner wall surface of each storage case 36 and the near-infrared ray IR1 reflected on the reflection suppressing layer 41 have phases opposite to each other.

The configuration other than the above is the same as that of the first embodiment. Therefore, the same elements as those described in the first embodiment are denoted by the same reference numerals, and redundant description will be omitted.
Therefore, according to the sixth embodiment, the same operation and effect as those of the first embodiment can be obtained. In addition, according to the sixth embodiment, a part of the near-infrared ray IR1 transmitted from each near-infrared ray sensor 11 is also applied to the inner wall surface of each storage case 36, mainly the cylindrical wall portion 37 and the flange wall portion 39. Irradiated. Here, if no countermeasures are taken for the irradiated portion, the near-infrared ray IR1 is reflected by the cylindrical wall portion 37, the flange wall portion 39, and the like. If the reflected near-infrared rays IR1 are mixed with the near-infrared rays IR2 reflected by the obstacle ahead and received by each of the near-infrared sensors 11, the distance and relative speed with respect to the obstacle ahead may be erroneously detected. is there.

  In this regard, in the sixth embodiment, a part of the near-infrared ray IR1 transmitted from each near-infrared ray sensor 11 is reflected by the inner wall surface of the housing case 36 and the reflection suppression layer 41, respectively. At this time, the near-infrared ray IR1 reflected on the inner wall surface of the housing case 36 passes through the reflection suppressing layer 41, and a phase shift occurs with the near-infrared ray IR1 reflected on the reflection suppressing layer 41. The near-infrared ray IR1 reflected on the inner wall surface of the housing case 36 and the near-infrared ray IR1 reflected on the reflection suppressing layer 41 have opposite phases, and the two near-infrared rays IR1 interfere with each other and are canceled out. Thus, the reflection of the near-infrared ray IR1 in the storage case 36 is reduced. Due to the reflection of the near-infrared ray IR1 in the housing case 36, each of the near-infrared ray sensors 11 can be prevented from erroneously detecting the distance or the relative speed to the obstacle in front.

  In addition, it is possible to prevent the amount of the near-infrared ray IR1 that passes through each storage case 36 from being reduced (loss) due to reflection. The degree of the near-infrared ray IR2 returned to the near-infrared ray sensor 11 with respect to the near-infrared ray IR1 transmitted from each near-infrared ray sensor 11 can be increased, and each of the near-infrared ray sensors 11 can properly perform the detection function.

(Seventh embodiment)
Next, a seventh embodiment of a cover for a near-infrared sensor will be described with reference to FIG.
In each of the near-infrared sensor covers (hereinafter, referred to as “cover 20F”) of the seventh embodiment, in addition to the configuration of the first embodiment, an antifouling layer 42 is formed on the front surface 22 of each cover main body 21 and the rear surface 23 has an antifouling layer. A cloudy layer 43 is formed. The antifouling layer 42 is composed of, for example, a film formed using a fluorine compound or the like. The anti-fog layer 43 is formed, for example, by applying an anti-fog agent to the back surface 23 of the cover body 21.

  The light transmittance of near-infrared rays IR1 and IR2 in each cover 20F formed by laminating the antifouling layer 42 and the antifogging layer 43 on each cover body 21 is 80% or more, and the light transmittance of visible light is 70%. % Or less.

The configuration other than the above is the same as that of the first embodiment. Therefore, the same elements as those described in the first embodiment are denoted by the same reference numerals, and redundant description will be omitted.
Therefore, according to the seventh embodiment, the same operations and effects as those of the first embodiment can be obtained. In addition, according to the seventh embodiment, it becomes difficult for dirt components such as raindrops and mud to adhere to the surface of the cover 20F. In addition, even if a dirt component adheres, it can be easily removed and the surface of the cover 20F can be kept clean.

Further, according to the seventh embodiment, even if each cover 20F cools and becomes lower than the dew point, it is possible to suppress condensation of water vapor in the air and condensation on the back surface of the cover 20F.
Therefore, it is possible to prevent the detection function of each near-infrared sensor 11 from being impaired due to the above-mentioned dirt component adhering to the front surface of each cover 20F or dew condensation on the back surface, thereby suppressing a decrease in detection accuracy. Can be.

(Eighth embodiment)
Next, an eighth embodiment of a cover for a near-infrared sensor will be described with reference to FIG.
In each near-infrared sensor cover (hereinafter, referred to as “cover 20G”) of the eighth embodiment, each of the cover main bodies 21 in the first embodiment includes a colored semi-transparent or transparent front main body 44 constituting a front part thereof, The cover main body 21 is divided into a colored translucent or transparent rear main body portion 45 constituting a rear portion. However, at least one of the front main body portion 44 and the rear main body portion 45 is colored and translucent. A liquid crystal light control film 46 including liquid crystal molecules in a transparent polymer is disposed between the front main body portion 44 and the rear main body portion 45.

  When a voltage is applied to the light control film 46, the liquid crystal molecules in the transparent polymer are regularly arranged in the direction in which light passes, so that the light control film 46 is in a state where light is easily transmitted (substantially transparent state), and the voltage application is stopped. Then, the liquid crystal molecules are arranged irregularly, so that it is difficult to transmit light.

  By utilizing such characteristics of the light control film 46, in the eighth embodiment, the voltage is applied to each light control film 46 when the vehicle 10 is running, and the voltage application is stopped when the vehicle 10 stops. I have. Switching between voltage application and application stop for each light control film 46 is performed based on the vehicle speed or the like by, for example, an electronic control device (not shown) mounted on the vehicle 10.

  The light transmittance of the near infrared rays IR1 and IR2 in each cover 20G in which the light control film 46 is disposed between the front main body portion 44 and the rear main body portion 45 is 80% or more, and the light transmission of visible light is performed. The rate is less than 70%. However, the value for visible light is the value when voltage application is stopped.

The configuration other than the above is the same as that of the first embodiment. Therefore, the same elements as those described in the first embodiment are denoted by the same reference numerals, and redundant description will be omitted.
Therefore, according to the eighth embodiment, the same operation and effect as those of the first embodiment can be obtained. In addition, according to the eighth embodiment, when the vehicle 10 travels, a voltage is applied to each light control film 46 by the electronic control unit, and the light control film 46 is in a state where light easily passes. Therefore, each light control film 46 is unlikely to hinder the transmission of near infrared rays IR1 and IR2 transmitted from each near infrared sensor 11 and reflected by a forward obstacle. Therefore, each near-infrared sensor 11 can exhibit its detection function.

  On the other hand, when the vehicle 10 is stopped, the application of the voltage to each light control film 46 is stopped by the electronic control unit, and the light control film 46 is in a state where it is difficult to transmit light. Therefore, the function of each cover 20 </ b> G hiding the near-infrared sensor 11 can be enhanced by the light control film 46. From the front of the vehicle 10, the respective near-infrared sensors 11 are more difficult to see.

The above embodiment can be implemented as a modified example in which this is changed as follows.
<About the first embodiment>
-Two or more of the fourth to eighth embodiments may be combined with the first embodiment.

<About the second embodiment>
-The colored translucent layer 27 may be laminated on the front surface 25 instead of the back surface 26 of each cover main body 24. Further, the colored translucent layer 27 may be laminated on both the front surface 25 and the back surface 26 of each cover body 24.

  -The second embodiment may be implemented by combining at least one of the contents of the third to eighth embodiments. When the third embodiment is combined, a part of the back surface 26 of each cover main body 24 is constituted by a first plane and a second plane.

<About the third embodiment>
3. Instead of the protrusion 33 constituted by the first plane 31 and the second plane 32 in FIG. 3, a concave part which is recessed forward is formed in a part of the cover body 28 as shown by a two-dot chain line in FIG. It may be formed. In this case, the first plane 31 is formed so as to be inclined with respect to the surface 29 such that the distance (thickness T) between the first plane 31 and the surface 29 gradually decreases toward the lower side. The second plane 32 is formed so as to be inclined in the direction opposite to the first plane 31 with respect to the surface 29 so that the distance (thickness T) between the second plane 32 and the surface 29 gradually increases toward the lower side. . The first plane 31 and the second plane 32 intersect in a sharp state at the deepest part of the recess.

Note that the angle formed by the surface 29 of the first plane 31 may be the same as or different from the angle formed by the surface 29 of the second plane 32.
-The third embodiment may be implemented by combining at least one content of the fourth to eighth embodiments.

<About the fourth embodiment>
-Each heating layer 34 may be laminated on the back surface 23 instead of the front surface 22 of each cover main body 21. However, since the heating layer 34 moves away from the surface of each cover 20D, the heat generated by the heating layer 34 is less likely to be transmitted to the snow attached to the surface of the cover 20D.

  As each of the heating layers 34, one having a resin sheet and a linear heater formed on the resin sheet may be used. As the resin sheet, for example, a sheet formed of a transparent resin material such as PC is used. As the linear heater, for example, a heater formed by printing a nichrome wire, a carbon heating element, a silver paste, or the like is used.

  This heater is desirably provided in a portion of the cover 20D outside the transmission region of the transmitted and reflected near-infrared rays IR1 and IR2. This can prevent the heater from hindering the transmission of the near infrared rays IR1 and IR2.

  When the heater generates heat, the heat is also transmitted to the transmission area surrounded by the heater in each cover 20D. Therefore, even if snow adheres to each cover 20D, the snow can be melted by the heat transmitted from the heater.

Note that the heater may be arranged alone, not as a part of the resin sheet.
<About Fifth Embodiment>
-Each reflection suppression layer 35 may be formed in the front surface 22 instead of the back surface 23 of each cover main body 21. By doing so, the reflection of the near infrared ray IR2 on the surface of each cover 20E is suppressed. The near-infrared ray IR2 that passes through the cover 20E and returns to the near-infrared sensor 11 increases. Therefore, each near-infrared sensor 11 can more appropriately exhibit the detection function.

  Further, each reflection suppressing layer 35 may be formed on both the front surface 22 and the rear surface 23 of each cover body 21. By doing so, it is possible to suppress both the reflection of the near infrared rays IR1 and IR2 on the front surface and the back surface of each cover 20E.

<About matters common to the fifth and sixth embodiments>
-As each reflection suppression layer 35 and 41, what laminated | stacked the some thin film may be employ | adopted. In this case, as the plurality of thin films, those having different refractive indexes and different thicknesses may be used. In this way, the phases of the near infrared rays IR1 and IR2 reflected by each thin film can be made different. For a wide range of wavelengths, the reflection of near infrared rays IR1 and IR2 can be reduced.

<About the seventh embodiment>
-In each cover 20F, one of the antifouling layer 42 and the antifogging layer 43 may be omitted.
A water-repellent layer, a hydrophilic layer, a photocatalytic layer, or the like may be formed on the surface 22 of each cover body 21 instead of the antifouling layer 42. By doing so, it is possible to prevent water drops, mud, and the like from adhering to the surface of each cover 20F.

  For example, the water-repellent layer is composed of an organic coating film, a silicone film, or the like. The water-repellent layer repels water adhering to the surface of the cover 20F and makes the cover 20F less likely to wet, thereby suppressing the formation of a water film on the surface of each cover 20F.

In the case where a hydrophilic layer is provided, dew condensation can be washed off by spreading the water in a film form.
Furthermore, when a photocatalyst layer is provided, the contact angle of water can be made close to zero by superhydrophilicity, so that condensation of water droplets can be suppressed.

<About the eighth embodiment>
As each light control film 46, a film different from the above-described liquid crystal system, for example, a SPD (Suspended Particle Device) system, an electrochromic system, a thermochromic system, or the like may be adopted.

<Matters Common to First, Second, Fourth to Eighth Embodiments>
The cover bodies 21 and 24 may have a uniform thickness T.
<Matters Common to First to Eighth Embodiments>
-Each cover 20A-20G is applicable also to the place where each near infrared sensor 11 is different from the front part of a vehicle, for example, the vehicle 10 attached to the rear part. An example of a target mounting location is a rear bumper. When each of the near-infrared sensors 11 transmits the near-infrared ray IR1 toward the rear of the vehicle 10, each of the covers 20 </ b> A to 20 </ b> G approaches the near-infrared sensor 11 to the rear of the vehicle 10 in the transmission direction. Placed at

  A hard coat layer having higher hardness than the member may be laminated on the surface of the member constituting the outermost part of each of the covers 20A to 20G. The hard coat layer is formed by applying a known surface treatment agent to a resin on the surface of the member. Examples of the surface treatment agent include acrylate-based, oxetane-based, and silicone-based organic hard coat agents, inorganic hard coat agents, and organic-inorganic hybrid hard coat agents.

  This can prevent the surfaces of the covers 20A to 20G from being damaged. In addition, it is possible to suppress deterioration or deterioration of each of the covers 20A to 20G due to sunlight, wind and rain, temperature change, and the like.

The technical ideas that can be grasped from the above embodiments are described below.
(B) The near-infrared sensor cover is a plate-like near-infrared sensor cover that is disposed in the vehicle in front of the near-infrared sensor transmitting direction of the near-infrared sensor, and at least a part of the cover in the thickness direction is colored. It is translucent, has a near-infrared ray transmittance of 80% or more, and has a visible light ray transmittance of 70% or less.

  According to the above configuration, the cover for the near-infrared sensor in which at least a part in the thickness direction is colored and translucent, and the light transmittance of visible light is 70% or less, the near-infrared sensor cover which is The function of hiding the near-infrared sensor is exhibited by being located in front of the transmission direction. Therefore, when the near-infrared sensor cover is viewed, the near-infrared sensor located behind the cover is difficult to see. Therefore, the appearance can be improved as compared with the case where the near-infrared sensor is not attached to the vehicle and the near-infrared sensor cover is not used.

  Further, when near infrared rays are transmitted from the near infrared ray sensor, the near infrared rays pass through the near infrared ray sensor cover disposed in the front in the transmission direction. The near-infrared light is reflected by the near-infrared sensor cover again after hitting an obstacle and received by the near-infrared sensor. Since the near-infrared sensor cover has a near-infrared ray transmittance of 80% or more, it hardly hinders the transmission of near-infrared rays. Therefore, the near-infrared sensor easily exerts the function of detecting the distance and the relative speed between the vehicle and the obstacle.

  (B) In the near-infrared sensor cover, at least a main part in the thickness direction is a near-infrared sensor cover constituted by a cover main body, the whole of the cover main body is colored and translucent, and the near-infrared ray in the cover main body is provided. Is preferably 80% or more, and the light transmittance of visible light is 70% or less.

  According to the above configuration, the cover main body that constitutes at least the main part in the thickness direction of the near-infrared sensor cover has a function of hiding the near-infrared sensor and makes the near-infrared sensor difficult to see. For this reason, the appearance of the near-infrared sensor becomes better than when the sensor is attached to the vehicle in a bare state.

  Further, the cover main body is unlikely to hinder the transmission of near-infrared rays transmitted from the near-infrared ray sensor and near-infrared rays reflected on an obstacle. Therefore, the near-infrared sensor easily exerts the detection function.

  (C) In the cover for a near-infrared sensor, the cover body has a front surface far from the near-infrared sensor and a back surface near the near-infrared sensor. It is preferable that the thickness of the main body is formed in a shape that gradually changes in a direction along the front surface and the back surface.

  According to the above configuration, in a cover body that is colored and translucent, the color density varies depending on the thickness. The thick part has a darker color than the thin part. Therefore, the design of the cover body is more varied than in the case where the thickness of the cover body is uniform and the color depth is constant at any part of the cover body.

  In addition, since the thickness of the cover body gradually changes in the direction along the front and back surfaces of the cover body, the color density changes in a continuous gradation in the direction along the front and back surfaces. Therefore, the change in the shade becomes more natural than when the shade of the color changes rapidly.

  (D) In the near-infrared sensor cover, a main part in the thickness direction is a near-infrared sensor cover formed of a transparent cover body, and the cover body has a surface farther from the near-infrared sensor; A back surface on the side close to the near-infrared sensor, a colored translucent layer is laminated on at least one of the front surface and the back surface of the cover body, and the colored translucent layer is laminated on the cover body. It is preferable that the light transmittance of near-infrared light is 80% or more and the light transmittance of visible light is 70% or less.

  According to the above configuration, the transparent cover main body constituting the main part in the thickness direction of the near-infrared sensor cover, and the colored translucent layer laminated on at least one of the front surface and the back surface hide the near-infrared sensor. It functions well and makes the near-infrared sensor difficult to see, so it looks better.

  Further, the cover main body and the colored translucent layer are unlikely to hinder the transmission of near infrared rays transmitted from the near infrared ray sensor or near infrared rays reflected on an obstacle. Therefore, the near-infrared sensor easily exerts the function of detecting the distance and the relative speed between the vehicle and the obstacle.

  (E) In the near-infrared sensor cover, the cover main body has a surface farther from the near-infrared sensor and a back surface closer to the near-infrared sensor, and the front surface is formed of a flat surface, A part of the back surface is inclined with respect to the front surface, so that the distance between the first surface and the first plane is gradually changed in a direction along the same surface, and the first surface is opposite to the first plane. By inclining so as to have a relationship, the distance between the first surface and the second surface is configured by a second plane in which a distance from the surface gradually changes in a direction along the same surface. Preferably cross in a pointed manner.

  According to the above configuration, a part of the visible light incident on the cover main body from the front side is reflected on the rear surface, and the first plane and the second plane have different reflection modes. Therefore, when the near-infrared sensor cover is viewed, the first plane and the second plane look different from each other, and the design of the cover body is rich in change.

  In particular, a point where the first plane and the second plane intersect in a pointed manner looks like a line. Therefore, by devising the position, the extending direction, the length, and the like of this portion, it is possible to make the design of the near-infrared sensor cover rich in variety.

  DESCRIPTION OF SYMBOLS 10 ... Vehicle, 11 ... Near infrared sensor, 20A, 20B, 20C, 20D, 20E, 20F, 20G ... Cover for near infrared sensor, 21, 24, 28 ... Cover body, 22, 25, 29 ... Surface, 23, 26 , 30 ... back surface, 27 ... colored translucent layer, 31 ... first plane, 32 ... second plane, IR1, IR1A, IR1B, IR2 ... near infrared ray, T ... thickness.

Claims (4)

In the vehicle, a plate-like near-infrared sensor cover that is disposed in front of the transmission direction of near-infrared transmitted from the near-infrared sensor,
The main part in the thickness direction is constituted by the cover body,
The cover body has a surface on the side far from the near-infrared sensor and a back surface on the side near the near-infrared sensor,
A reflection suppressing layer is laminated on at least one of the front surface and the rear surface of the cover body,
A cover for a near-infrared sensor in which a near-infrared ray transmittance in a layer in which the reflection suppressing layer is laminated on the cover body is 80% or more and a visible ray light transmittance is 70% or less. A housing case for housing the near-infrared sensor is attached in a state where a wall portion thereof is close to a back surface of the cover body,
The near-infrared sensor cover according to claim 1, wherein the reflection suppressing layer is laminated between the back surface and the wall.   3. The near-infrared sensor cover according to claim 1, wherein the entire cover body is formed in a shape in which the thickness of the cover body gradually changes in a direction along the front surface and the back surface. 4. The surface is constituted by a plane,
A part of the back surface is inclined with respect to the front surface, so that a first plane in which a distance from the front surface gradually changes in a direction along the same surface is opposite to the first plane with respect to the front surface. By being inclined so as to have the relationship of, a second plane whose interval with the surface gradually changes in a direction along the surface,
The near-infrared sensor cover according to any one of claims 1 to 3, wherein the first plane and the second plane intersect in a sharp state.