JP6890013B2 - Transparent cover - Google Patents

Description

The present invention relates to a transmissive cover used in a vehicle.

In recent years, adaptive cruise control (ACC) is known, which measures the inter-vehicle distance or relative speed between a vehicle in front and the own vehicle using millimeter waves or infrared rays, accelerates or decelerates the own vehicle, and controls the inter-vehicle distance. As described in Patent Document 1, a vehicle radar device equipped with an adaptive cruise control system is provided behind the front grill of the vehicle.

Japanese Patent No. 4888732

In the configuration of Patent Document 1, a transparent cover is provided in the front grill.
By the way, the vehicle radar device and the camera may be used together in order to improve the function of the adaptive cruise control or to prepare for the failure of the vehicle radar device. If the camera is installed on the front grill or the transparent cover, the camera will be visually recognized from between the front grills. Therefore, the aesthetic appearance of the vehicle may be spoiled and the design of the vehicle may be deteriorated.

The present invention has been created in view of these respects, and an object of the present invention is to provide a transmission cover that can be used in combination with a vehicle radar device and a camera to improve the design of the vehicle.

The transmissive cover of the present invention is used in a vehicle (1), and includes a transparent member (20), a design layer (30), a first intermediate layer (40), an optical control layer (50), a base material (70), and a camera ( 80) is provided.
The transparent member is made of resin and is capable of transmitting radio waves and light.
The design layer is provided on the end face (21) of the transparent member.
The first intermediate layer is provided so as to sandwich the design layer with the transparent member, is made of resin, and is capable of transmitting radio waves and light.

The optical control layer is provided so as to sandwich the first intermediate layer between the transparent member or the design layer, is made of indium or tin, and can transmit and reflect light from the outside.
The base material is provided so as to sandwich the optical control layer with the first intermediate layer, is made of resin, and has holes (71).
The camera is fitted to the base material through a hole, faces the optical control layer , collects radio waves and light transmitted through the transparent member, the first intermediate layer, and the optical control layer from the outside, and images the outside of the vehicle. It is possible.

The optical control layer is made of indium or tin and is capable of transmitting and reflecting light from the outside. The light transmitted through the light control layer allows the camera to image the outside of the vehicle. Therefore, the vehicle radar device and the camera can be used together. In addition, the optical control layer prevents the camera from being recognized when viewed from the outside. Since the camera is not recognized from the outside, the aesthetic appearance of the vehicle is not spoiled and the design of the vehicle is improved.

The block diagram of the vehicle which uses the transmission cover by one Embodiment of this invention. FIG. 6 is a configuration diagram of a vehicle radar device in which a transmission cover according to an embodiment of the present invention is used. Sectional drawing of the transmission cover according to one Embodiment of this invention. FIG. 3 is an enlarged view of part IV. The schematic diagram for demonstrating the structure of the optical control layer used for the transmission cover by one Embodiment of this invention. The explanatory view for demonstrating the incident light from the light control layer used for the transmission cover according to one Embodiment of this invention to a camera. The explanatory view for demonstrating the reflection of light in the light control layer used for the transmission cover by one Embodiment of this invention. The relationship diagram of the control layer thickness and the light transmittance of the transmission cover by one Embodiment of this invention. The block diagram of the vehicle which uses the transparent cover of the comparative example.

Hereinafter, the transparent cover according to the embodiment of the present invention will be described with reference to the drawings. In a plurality of embodiments, substantially the same configuration will be described with the same reference numerals. Further, the term "the present embodiment" includes a plurality of embodiments. The transmissive covers of these embodiments are provided on the vehicle.

First, the vehicle 1 in which the transparent cover of the present embodiment is used will be described.
The forward direction of the vehicle 1 is "front", and the backward direction of the vehicle 1 is "rear". The upper side when viewed from the forward direction is "upper", and the lower side when viewed from the forward direction is "lower". The vertical direction is the same as the vehicle height direction. The right side when viewed from the forward direction is "right", and the left side when viewed from the forward direction is "left". The left-right direction is the same as the vehicle width direction.

As shown in FIG. 1, the vehicle 1 includes a front grill 2, a vehicle radar device 3, and a transmission cover 10.
The front grill 2 is provided at the front portion of the vehicle 1 and is provided between the headlights 4, and air can be introduced into the engine room of the vehicle 1 from the outside. The front grill 2 may be provided at the rear of the vehicle 1.

As shown in FIG. 2, the vehicle radar device 3 is provided on the rear side of the front grill 2 and can transmit and receive millimeter waves or infrared rays.
When the vehicle radar device 3 transmits millimeter waves or infrared rays, the transmitted millimeter waves or infrared rays pass through the transmission cover 10. The vehicle radar device 3 receives millimeter waves or infrared rays reflected from a target such as a vehicle in front. In FIG. 2, infrared rays are hatched with diagonal lines so that millimeter waves or infrared rays are clearly defined.

The vehicle radar device 3 measures the distance, angle, and relative velocity from the vehicle 1 to the target by transmitting and receiving millimeter waves or infrared rays.
The distance from the vehicle 1 to the target is measured from the time difference between transmission and reception extracted by applying appropriate modulation to the amplitude, frequency or phase of the transmission signal and correlating it with the reception signal.
The angle from vehicle 1 to the target is measured by scanning millimeter waves or infrared rays with the transmission and reception of millimeter waves or infrared rays limited to a limited direction.
The relative velocity from the vehicle 1 to the target is measured by extracting the frequency deviation generated in the millimeter wave or infrared ray reflected by the Doppler effect.

In recent years, adaptive cruise control (ACC) is known, which measures the inter-vehicle distance or relative speed between a vehicle in front and the own vehicle using millimeter waves or infrared rays, accelerates or decelerates the own vehicle, and controls the inter-vehicle distance.
The vehicle radar device and the camera may be used together to improve the function of the adaptive cruise control or to prepare for the failure of the vehicle radar device.
As shown in FIG. 9, since the camera 91 is also used, when the camera 91 is provided, the camera 91 is visually recognized from between the front grills 92. Therefore, the aesthetic appearance of the vehicle 90 may be spoiled, and the design of the vehicle 90 may be deteriorated.

Therefore, the transmission cover 10 of the present embodiment can be used in combination with the vehicle radar device 3 and the camera 80, and the design of the vehicle 1 is improved.

(One Embodiment)
As shown in FIG. 3, the transmission cover 10 includes a transparent member 20, a design layer 30, a first intermediate layer 40, an optical control layer 50, a second intermediate layer 60, a base material 70, and a camera 80. In FIG. 3, in order to clarify the locations of the design layer 30 and the optical control layer 50, the design layer 30 and the optical control layer 50 are shown by a dot pattern.

The transparent member 20 is provided on the front side of the vehicle 1 and is capable of transmitting radio waves and light, and is capable of transmitting millimeter waves or infrared rays.
Further, the transparent member 20 is made of resin. The resin used for the transparent member 20 is, for example, polycarbonate or acrylic.
Further, the transparent member 20 has a plurality of recesses 22 formed on the rear end surface 21.
The recess 22 is formed in the upper end 23, the central portion 24, or the lower end portion 25 of the transparent member 20.

The design layer 30 is formed on the rear end surface 21 of the transparent member 20 excluding the plurality of recesses 22, and displays various designs. The design of this embodiment is "SR".
Further, the design layer 30 is formed by depositing metal.

The first intermediate layer 40 is formed on the rear end surface 21 of the transparent member 20 or the rear end surface 31 of the design layer 30.
The first intermediate layer 40 is provided so as to sandwich the design layer 30 with the transparent member 20, and is provided between the transparent member 20 or the design layer 30 and the optical control layer 50.
Further, the first intermediate layer 40 is made of a resin capable of transmitting radio waves and light, similarly to the transparent member 20.
The first intermediate layer 40 is formed by painting or vapor deposition.

The optical control layer 50 is formed on the rear end surface 41 of the first intermediate layer 40. The thickness of the optical control layer 50 is defined as the control layer thickness Tc [nm].
Further, the optical control layer 50 is provided so as to sandwich the first intermediate layer 40 between the transparent member 20 or the design layer 30, and is provided between the first intermediate layer 40 and the second intermediate layer 60. ..

Further, the optical control layer 50 is made of indium (In). The optical control layer 50 may be made of tin (Sn). By using tin, it has the same effect as indium.
Further, the optical control layer 50 is formed by vacuum deposition. The optical control layer 50 may be formed by a physical vapor deposition method (PVD) such as sputtering.

As shown in FIGS. 4 and 5, a plurality of indium particles 52 are deposited, and the optical control layer 50 is formed in an island-like structure.
In the light control layer 50, a space through which light can be transmitted is formed between the indium particles 52, and light from the outside can be transmitted and reflected. In FIG. 4, indium particles 52 are exaggerated and described in order to clarify the indium particles 52, and diagonal hatching is omitted. Similarly, in FIG. 5, the indium particles 52 are exaggerated and described.

The second intermediate layer 60 is formed on the rear end surface 51 of the optical control layer 50.
Further, the second intermediate layer 60 is provided so as to sandwich the optical control layer 50 with the first intermediate layer 40, and is provided between the optical control layer 50 and the base material 70.
The second intermediate layer 60 is made of resin. The resin used for the second intermediate layer 60 is, for example, AES. AES is an abbreviation for acrylonitrile styrene acrylate.
The second intermediate layer 60 is formed by painting or vapor deposition.

The maximum height roughness of the surface of the design layer 30 is defined as the design layer roughness Rz_D [nm]. The maximum height roughness of the surface of the first intermediate layer 40 is defined as the first intermediate layer roughness Rz_M1 [nm]. The maximum height roughness of the surface of the optical control layer 50 is defined as the optical control layer roughness Rz_C [nm]. The maximum height roughness of the surface of the second intermediate layer 60 is defined as the second intermediate layer roughness Rz_M2 [nm].
Each maximum height roughness is a definition based on JIS_B_0601. The device for measuring the maximum height roughness is, for example, a contact type surface roughness measuring machine using a stylus or the like or a non-contact type surface roughness measuring machine using a laser or the like.

The first intermediate layer roughness Rz_M1 is set to be smaller than the design layer roughness Rz_D, that is, Rz_M1 <Rz_D.
The second intermediate layer roughness Rz_M2 is set to be smaller than the optical control layer roughness Rz_C, that is, Rz_M2 <Rz_C.

Substrate 70 is formed on the rear end surface 61 of the second intermediate layer 60 is provided so as to sandwich the light control layer 50 between the first intermediate layer 40.
Further, the base material 70 is made of the same resin as the second intermediate layer 60.
Further, the substrate 70 has holes 71 at the ends 72.

The camera 80 is fitted to the base material 70 through the hole 71, and is provided so as not to face the second intermediate layer 60.
Further, the camera 80 is provided outside the irradiation range of millimeter waves or infrared rays of the vehicle radar device 3.
Further, the lens 81 of the camera 80 faces the optical control layer 50.

The camera 80 includes an image pickup optical system having a wide-angle lens, and also has a CCD type or CMOS type image pickup element, and can output an image pickup as a moving image having several or more frames per second. CCD is an abbreviation for Charge Coupled Device, and is a sensor using a charge coupling element. CMOS is an abbreviation for Complementary MOSFET. Further, the camera 80 may be an image radar device capable of transmitting and receiving millimeter waves to take an image.
The camera 80 can collect radio waves and light transmitted through the transparent member 20, the first intermediate layer 40, and the optical control layer 50 from the outside, and can image the front of the vehicle 1.

The operation of the optical control layer 50 of the transmission cover 10 of the present embodiment will be described.
As shown in FIG. 6, the light transmitted from the outside through the transparent member 20 and the first intermediate layer 40 is transmitted through the space between the indium particles 52 and is transmitted through the light control layer 50. The transmitted light is incident on the camera 80. The camera 80 takes an image from the incident light. In FIG. 6, the light incident on the camera 80 is shown by a long-dotted line.

As shown in FIG. 7, when the light transmitted through the transparent member 20 and the first intermediate layer 40 from the outside hits the indium particles 52, the light is reflected. In FIG. 7, the light reflected by the light control layer 50 is shown by a chain double-dashed line.
The illuminance on the camera 80 side, the control layer thickness Tc, or the like is set so that the amount of light transmitted through the light control layer 50 is smaller than the amount of light reflected by the light control layer 50. Since the amount of light reflected by the light control layer 50 is large, only the reflected image of the light control layer 50 is recognized and the camera 80 is not recognized when viewed from the outside.

(effect)
[1] The light control layer 50 is made of indium and is capable of transmitting and reflecting light from the outside. The light transmitted through the light control layer 50 allows the camera 80 to image the front of the vehicle 1. Therefore, the vehicle radar device 3 and the camera 80 can be used together. Further, the optical control layer 50 does not recognize the camera 80 when viewed from the outside. Since the camera 80 is not recognized, the aesthetic appearance of the vehicle 1 is not spoiled, and the design of the vehicle 1 is improved.

[2] As shown in FIG. 8, as the thickness Tc of the control layer increases, the light transmittance X of the light control layer 50 decreases. The light transmittance X is calculated by the ratio of the intensity of the incident light on the light control layer 50 and the intensity of the transmitted light on the light control layer 50. Based on the characteristics of the transmissive cover 10 used in one embodiment, when the control layer thickness Tc is 1 nm or less, the light transmittance X is equal to or more than the permissible value.

Further, as the thickness Tc of the control layer increases, the reflectance R of the optical control layer 50 increases. The reflectance R is a relative reflectance or an absolute reflectance.
When examined based on the characteristics of the transmission cover 10, when the control layer thickness Tc is larger than zero, that is, when the optical control layer 50 is provided, the reflectance R becomes equal to or higher than the permissible value, and the camera 80 becomes invisible.

[3] The first intermediate layer roughness Rz_M1 is set to be smaller than the design layer roughness Rz_D. The surface on which the optical control layer 50 is deposited is smoothed, that is, leveled by the first intermediate layer 40. Therefore, when the optical control layer 50 is vapor-deposited, the surface tension generated between the first intermediate layer 40 and the optical control layer 50 becomes small. The adhesion between the first intermediate layer 40 and the optical control layer 50 is improved more than the adhesion between the design layer 30 and the optical control layer 50. This facilitates the formation of the optical control layer 50.

[4] The optical control layer 50 is sandwiched between the first intermediate layer 40 and the second intermediate layer 60. The internal stress of the optical control layer 50 by the first intermediate layer 40 is relaxed by the internal stress of the optical control layer 50 by the second intermediate layer 60. Therefore, the adhesion of the optical control layer 50 is improved.

[5] Since the optical control layer 50 has an island-like structure, the surface roughness is relatively large. In the transmission cover 10, the second intermediate layer roughness Rz_M2 is set to be smaller than the optical control layer roughness Rz_C. As a result, the interface between the optical control layer 50 and the second intermediate layer 60 is smoothed. When recognizing an image of light reflected by the light control layer 50, the light control layer 50 looks beautiful.

(Other embodiments)
[I] The transparent cover may be provided on a side portion such as the inside of a vehicle door. Further, the transparent cover may be provided at the rear of the vehicle. At this time, the camera with the transmissive cover can take an image of the periphery of the vehicle.

[Ii] The roughness of the design layer, the first intermediate layer, the second intermediate layer and the optical control layer is not limited to the maximum height roughness, but the arithmetic average roughness Ra, the average height Rc or the root mean square height Rq. And so on.
As described above, the present invention is not limited to such embodiments, and can be implemented in various embodiments without departing from the spirit of the invention.

1 ... Vehicle,
20 ... Transparent member,
30 ... Design layer,
40 ... 1st intermediate layer,
50 ... Optical control layer,
70 ・ ・ ・ Base material,
80 ... Camera.

Claims (6)

A transparent cover used for the vehicle (1).
A transparent member (20) that is made of resin and is capable of transmitting radio waves and light,
A design layer (30) provided on the end face (21) of the transparent member,
A first intermediate layer (40), which is provided so as to sandwich the design layer with the transparent member, is made of resin, and is capable of transmitting radio waves and light, and
An optical control layer (50) provided so as to sandwich the first intermediate layer between the transparent member or the design layer, formed of indium or tin, and capable of transmitting and reflecting light from the outside.
A base material (70) which is provided so as to sandwich the optical control layer between the first intermediate layer and is made of resin and has holes (71).
The vehicle is fitted with the base material through the hole, faces the optical control layer, and collects radio waves and light transmitted from the transparent member, the first intermediate layer, and the optical control layer from the outside. A camera (80) capable of capturing the outside of the
A transparent cover with. The transmission cover according to claim 1, wherein the thickness (Tc) of the optical control layer is 1 nm or less. The transparent cover according to claim 1 or 2, wherein the roughness of the first intermediate layer is smaller than the roughness of the design layer. The transmission cover according to any one of claims 1 to 3, further comprising a second intermediate layer (60) provided between the optical control layer and the base material and formed of a resin. The transmission cover according to claim 4, wherein the roughness of the second intermediate layer is smaller than the roughness of the optical control layer. The transparent cover according to any one of claims 1 to 5, wherein the transparent member has a plurality of recesses (22).

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