阅读说明：本技术 电磁波利用系统 (Electromagnetic wave utilization system ) 是由 太田浩司 福田浩太郎 中村真一郎 横山佳之 于 2018-06-01 设计创作，主要内容包括：电磁波利用系统包括电磁波装置(100、201)和加热器(11、21)；电磁波装置进行电磁波的发送和接收中的至少一者；加热器对电磁波装置所利用的电磁波所通过的通过部(1、203)进行加热；加热器具备有电流流动便发热的发热体(111)和保持发热体的保持部(112)；发热体和保持部对电磁波装置所利用的电磁波透明；由此,能够在不妨碍电磁波通过的情况下将通过部加热。(An electromagnetic wave utilization system is provided with an electromagnetic wave device (100, 201) and a heater (11, 21), wherein the electromagnetic wave device transmits and receives electromagnetic waves at least , the heater heats a passage section (1, 203) through which the electromagnetic waves used by the electromagnetic wave device pass, the heater is provided with a heating element (111) which generates heat when a current flows and a holding section (112) which holds the heating element, and the heating element and the holding section are transparent to the electromagnetic waves used by the electromagnetic wave device, whereby the passage section can be heated without preventing the passage of the electromagnetic waves.)

An electromagnetic wave utilization system of , comprising:

an electromagnetic wave device (100, 201) that transmits and receives electromagnetic waves at least , and

a heater (11, 21) that heats a passage portion (1, 203) through which the electromagnetic waves used by the electromagnetic wave device pass,

the heater comprises a heating element (111) which generates heat when current flows and a holding part (112) which holds the heating element,

the heating element and the holding portion are transparent to the electromagnetic wave used by the electromagnetic wave device.

2. The electromagnetic wave utilization system according to claim 1, wherein said heat generating body is formed of a carbon nanotube.

3. The electromagnetic wave utilization system according to claim 2, wherein the passage portion is formed of resin.

4. The electromagnetic wave utilization system of any one of claims 1 to 3, ,

the electromagnetic wave device (201) is a device that irradiates laser light via the passage portion and receives the laser light reflected by an object,

the electromagnetic wave is the laser light utilized by the electromagnetic wave device,

the passage section is a cover (203) that protects the electromagnetic wave device.

5. The electromagnetic wave utilization system of any one of claims 1 to 3, ,

the electromagnetic wave device is a camera (100) that photographs the outside of the vehicle via the passage portion,

the passage section is a window (1) of the vehicle,

the heater is arranged at a position in the window corresponding to a field of view (v1) of the camera.

6. The electromagnetic wave utilization system according to claim 5,

the device is provided with heater control units (13, 14, 15) which determine the possibility of window fogging and cause current to flow through the heaters when the possibility of window fogging becomes high.

7. The electromagnetic wave utilization system according to claim 5,

the window fog control device is provided with heater control parts (13, 14, 15) which judge whether the window is fogging or not and make current flow in the heater when judging that the window is fogging.

8. The electromagnetic wave utilization system of any one of claims 5 to 7, ,

the heater has counter electrodes (113a, 113b) connected to the heating element,

the electrodes are arranged outside the field of view (v 1).

9. The electromagnetic wave utilization system of any one of claims 1 to 3, ,

the electromagnetic wave device is a device that irradiates visible light through the passage portion,

the electromagnetic wave is the visible light irradiated by the electromagnetic wave device,

the passage portion is a cover that protects the electromagnetic wave device.

Technical Field

The present invention relates to an electromagnetic wave utilization system that utilizes electromagnetic waves.

Background

Patent document 1 discloses an on-vehicle camera for capturing a rearward view of a vehicle. In this conventional technique, the vehicle-mounted camera is disposed on the ceiling in the vehicle cabin in the vicinity of the rear window, and captures an image of the outside through the rear window.

In this prior art, the vehicle-mounted camera is arranged so that the heater wire of the rear window defogger does not come within the shooting range. The defogger is a device that removes fog on the rear window by heating the rear window by a heating wire.

Prior art documents

Patent document

Patent document 1: japanese unexamined patent publication No. 2-300715

According to this prior art, the vehicle-mounted camera is disposed such that the heater wire of the rear window defogger does not come within the shooting range, and therefore the field of view of the vehicle-mounted camera is not obstructed by the heater wire of the defogger.

However, in this conventional technique, since the heater wire of the defogger is not present in the imaging range, the fog in the imaging range cannot be satisfactorily eliminated. Therefore, in the case of rear window fogging, visibility of the field of view of the vehicle-mounted camera may not be ensured satisfactorily.

This possibility occurs not only in an on-vehicle camera that captures visible light but also in various electromagnetic wave utilization systems that utilize electromagnetic waves, such as an automotive laser device that transmits and receives laser light.

Disclosure of Invention

In view of the above problems, an object of the present invention is to provide an electromagnetic wave utilization system capable of heating a passage portion through which an electromagnetic wave passes without preventing the passage of the electromagnetic wave.

An electromagnetic wave utilization system according to an embodiment of the present invention includes an electromagnetic wave device that transmits and receives electromagnetic waves at least , and a heater that heats a passage portion through which the electromagnetic waves used by the electromagnetic wave device pass.

This allows the passage portion to be heated without preventing the passage of electromagnetic waves.

Drawings

Fig. 1 is a sectional view of a vehicle mounted with an image pickup device for a vehicle in th embodiment.

Fig. 2 is a partially enlarged sectional view showing the vehicle imaging device of fig. 1.

Fig. 3 is a top view of the heater.

Fig. 4 is a flowchart showing control processing executed by the control device of the vehicle imaging device according to embodiment .

Fig. 5 is a sectional view showing a laser device according to a second embodiment.

Fig. 6 is a view in the direction VI of fig. 5.

Detailed Description

Hereinafter, embodiments will be described with reference to the drawings. In the following embodiments, the same or equivalent portions are denoted by the same reference numerals in the drawings.

(embodiment )

The following describes the image pickup apparatus for a vehicle according to the present embodiment with reference to the drawings, in which vertical and front-rear arrows indicate the vertical and front-rear directions of the vehicle, and the image pickup apparatus for a vehicle is an electromagnetic wave utilization system that utilizes types of visible light as electromagnetic waves.

As shown in fig. 1, the imaging unit 10 is attached to a surface of a front windshield 1 of a vehicle on the inner side of the vehicle cabin. The imaging unit 10 is attached to a substantially central portion in the left-right direction above the front windshield 1 of the vehicle. The imaging unit 10 is located near a not-shown rearview mirror.

As shown in fig. 2, the imaging unit 10 includes a camera 100 and a housing 101, the camera 100 images the outside in front of the vehicle via a window (in this example, a front windshield 1), the camera 100 is an electromagnetic wave device that images types of visible light as electromagnetic waves, and the front windshield 1 is a passage through which the visible light imaged by the camera 100 passes.

Image data captured by the camera 100 is input to the image processing apparatus 20. The image processing device 20 processes the image data of the camera 100, thereby detecting an object in front of the vehicle. The detection result of the image processing device 20 is output to the collision safety control device 26. The collision safety control device 26 controls braking and the like of the vehicle based on the detection result of the image processing device 20, thereby preventing collision of the vehicle.

The camera 100 is housed in a housing 101. The housing 101 is a member constituting a casing of the image pickup unit 10. The housing 101 may be in close contact with the front windshield 1, or may be provided with a predetermined gap from the front windshield 1.

The front windshield 1 is provided with a heater 11. The heater 11 heats the front windshield 1 by generating heat, and thereby functions to remove fog on the surface of the front windshield 1 on the vehicle interior side or melt snow or frost on the surface of the front windshield 1 on the vehicle exterior side.

The heater 11 is a transparent film-like member. The heater 11 is attached to the surface of the front windshield 1 on the vehicle interior side. The heater 11 may be embedded in the front windshield 1.

As shown in fig. 3, the heater 11 includes a carbon nanotube 111 and a binder (binder) 112. The carbon nanotube 111 is a heating element that generates heat when current flows. In fig. 3, the carbon nanotubes 111 are illustrated as dashed straight lines for convenience of illustration.

The carbon nanotube 111 (also referred to as "CNT") is a carbon crystal having a hollow cylindrical structure, the diameter of the carbon nanotube 111 is 0.7nm to 70nm, which is about parts per ten thousand of the hair, and the carbon nanotube 111 has a tube shape with a length of several tens of μm or less.

The bonding member 112 is a holding portion that holds the carbon nanotube 111. The material of the engaging member 112 is transparent resin.

For example, the heater 11 is a thin film in which carbon nanotubes 111 are dispersed in the bonding member 112. The heater 11 may have a plurality of line segment-shaped heat generating lines using wires formed of carbon nanotubes 111. The diameter of the wire formed of the carbon nanotube 111 is about several μm.

The carbon nanotube 111 is a component that is so thin as to be unrecognizable by the naked eye. The wire formed using the carbon nanotube 111 is also a component that is so thin as to be invisible to the naked eye. Therefore, the heater 11 appears transparent to the naked eye. The carbon nanotubes 111 can absorb light and prevent scattering of the light.

The heater 11 has counter electrodes 113a, 113b the electrodes 113a, 113b are connected to the carbon nanotubes 111.

When a dc voltage is applied from the battery 12 of the vehicle to the electrodes 113a and 113b, a current flows through the carbon nanotube 111, and the carbon nanotube 111 generates heat. The electrodes 113a, 113b are formed in an elongated shape along the edge portion of the heater 11.

The current-carrying portion 13 switches between applying and interrupting the dc voltage from the battery 12 to the electrodes 113a and 113 b. The energizing portion 13 has a relay or a switch. The operation of the current carrying portion 13 is controlled by a heater control device 14.

The heater 11 is arranged to overlap the entire range of the field of view v1 of the camera 100 in fig. 3, the field of view v1 of the camera 100 is indicated by a two-dot chain line for easy understanding and the heater 11 is arranged to reach a range larger than the field of view v1 of the camera 100 by turns.

The electrodes 113a, 113b of the heater 11 are arranged outside the field of view v1 of the camera 100. Thereby, the view v1 of the camera 100 is prevented from being obstructed by the heater 11.

The heater control device 14 is constituted by a well-known microcomputer including a CPU (central processing unit), a ROM (read only memory), a RAM (random access memory), and the like, and a peripheral circuit thereof, and performs various calculations and processes according to a control program stored in the ROM, thereby controlling the operation of various devices connected to the output side.

A window surface humidity sensor 15 is connected to the input side of the heater control device 14. The window surface humidity sensor 15 is constituted by a window vicinity humidity sensor, a window vicinity air temperature sensor, and a window surface temperature sensor.

The window vicinity humidity sensor detects the relative humidity of the air in the vehicle cabin in the vicinity of the front windshield 1 in the vehicle cabin. Hereinafter, the relative humidity is referred to as "relative humidity in the vicinity of the window". The window vicinity air temperature sensor detects the temperature of the air in the vehicle cabin in the vicinity of front windshield 1. The window surface temperature sensor detects the surface temperature of the front windshield 1.

The current-carrying section 13, the heater control device 14, and the window surface humidity sensor 15 are heater control sections that control the operation of the heater 11.

The heater control device 14 executes a control process shown in the flowchart of fig. 4. Fig. 4 is a flowchart showing a subroutine of a control routine executed by the heater control device 14.

First, in step S100, the relative humidity RHW of the cabin inner surface of the front windshield 1 is calculated based on the detection value of the window surface humidity sensor 15. Hereinafter, the relative humidity RHW is referred to as "window surface relative humidity RHW".

The window surface relative humidity RHW is an index indicating the possibility of fogging of the front windshield 1. Specifically, the larger the value of the window surface relative humidity RHW, the higher the possibility of fogging of the front windshield 1.

At step S110, it is determined whether or not the window surface relative humidity RHW is equal to or greater than the threshold value α, and when it is determined at step S110 that the window surface relative humidity RHW is equal to or greater than the threshold value α, the process proceeds to step S120 to heat the heater 11, and specifically, the heater control device 14 applies a dc voltage from the battery 12 of the vehicle to the electrodes 113a, 113b of the heater 11.

Accordingly, when there is a high possibility of fogging of the front windshield 1, the front windshield 1 can be heated by the heater 11 to prevent fogging of the front windshield 1, or when the front windshield 1 is fogged, the front windshield 1 can be heated by the heater 11 to remove fogging on the front windshield 1.

, when it is determined in step S110 that the window surface relative humidity RHW is not equal to or higher than the threshold α, the process proceeds to step S130 to stop the heater 11 from generating heat, and specifically, the heater control device 14 cuts off the application of the dc voltage to the electrodes 113a and 113b of the heater 11.

In the present embodiment, the heater 11 that heats the front windshield 1 is disposed at a position corresponding to the field of view v1 of the camera 100 in the front windshield 1. The heater 11 has carbon nanotubes 111 and a bonding member 112. The carbon nanotube 111 is a component that cannot be recognized with the naked eye. The engaging member 112 is made of a transparent material.

Accordingly, since the heater 11 is present in the field of view v1 of the camera 100, the fog in the field of view v1 can be eliminated well. Further, since the carbon nanotubes 111 of the heater 11 are components that cannot be recognized by the naked eye and the bonding members 112 of the heater 11 are formed of a transparent material, the heater 11 can be made transparent. Therefore, the heater 11 can be prevented from obstructing the view v1 of the camera 100.

In the present embodiment, the heating element of the heater 11 is formed of the carbon nanotube 111. Accordingly, the carbon nanotubes 111 can absorb light and prevent scattering of the light, and thus the transparency of the heater 11 can be improved.

In the present embodiment, the current carrying portion 13, the heater control device 14, and the window surface humidity sensor 15 determine the possibility of fogging of the front windshield 1, and when the possibility of fogging of the front windshield 1 becomes high, current is caused to flow through the heater 11. This enables the heater 11 to operate efficiently.

The current-carrying section 13, the heater control device 14, and the window surface humidity sensor 15 may determine whether the front windshield 1 is fogging, and may cause the current to flow through the heater 11 when it is determined that the front windshield 1 is fogging. This enables the heater 11 to operate efficiently.

In the present embodiment, the electrodes 113a and 113b of the heater 11 are visually recognizable, and are disposed outside the visual field v 1. This can prevent the electrodes 113a and 113b, which can be recognized by naked eyes, from interfering with the field of view v1 of the camera 100.

(second embodiment)

In the above embodiment, the vehicle imaging device including the heater 11 is described, and in the present embodiment, the vehicle laser device 24 including the heater 21 is described with reference to fig. 5 and 6.

The laser device 24 for a vehicle measures a distance, a direction, an attribute, and the like of an object based on a time from when a laser beam is irradiated in a pulse shape until the laser beam is reflected by the object, and is used as a sensor for automatic driving of a vehicle, for example.

The laser device 24 for a vehicle includes a laser transceiver 201, a housing 202, and a cover 203. The laser transceiver 201 is a device that detects an object or measures a distance to the object by irradiating laser light and receiving the laser light reflected by the object.

For example, the laser device 24 for a vehicle is mounted on a bumper, not shown, of a vehicle, and irradiates laser light toward the front of the vehicle and receives laser light returning from the front of the vehicle. The laser light irradiated by the vehicle laser device 24 is, for example, laser light having a wavelength of near infrared rays.

The operation of the laser transceiver 201 is controlled by the automatic driving control device 22. The detection result and the measurement result of the laser transceiver 201 are input to the automatic driving control device 22. The automatic driving control device 22 performs automatic driving of the vehicle based on the detection result and the measurement result of the laser transceiver 201.

The laser transceiver 201 is housed in a space sealed by a case 202 and a cover 203. The housing 202 and the cover 203 are members that house the laser transceiver 201 and protect the laser transceiver 201. The housing 202 is disposed in a region through which laser light transmitted or received by the laser transceiver 201 does not pass. The cover 203 is disposed in a region through which laser light transmitted or received by the laser transceiver 201 passes. The cover 203 is formed of resin.

The heater 21 is a transparent film-like member similar to the heater 11 of the -th embodiment, and includes carbon nanotubes and a bonding material, and the carbon nanotubes and the bonding material of the heater 21 are transparent to the laser light transmitted or received by the laser transceiver 201.

The transparency of the heater 21 to the laser light transmitted or received by the laser transceiver 201 is 80% or more. Therefore, the heater 21 can be prevented from interfering with the passage of the laser light in the cover 203. The transparency of the heater 21 to the laser light transmitted or received by the laser transceiver 201 is preferably about 95%.

The heater 21 is adhered to the inner surface of the cover 203 by adhesion. The heater 21 may be attached to the outer surface of the cover 203. The heater 21 may be insert molded on the cover 203.

The heater 21 has flexibility to follow the curved shape of the surface of the cover 203 the heater 21 is provided on part or the whole of the area of the cover 203 through which the laser transmitted or received by the laser transceiver 201.

The cover 203 and the heater 21 are transparent to the laser light transmitted or received by the laser transceiver 201. In other words, the cover 203 and the heater 21 transmit laser light transmitted or received by the laser transceiver 201.

A dc voltage is applied from a battery, not shown, of the vehicle to an electrode, not shown, of the heater 21, and a current is caused to flow through the carbon nanotubes, not shown, of the heater 21, thereby causing the carbon nanotubes to generate heat. The electrodes of the heater 21 are formed in an elongated shape along the edge portion of the heater 21.

Since the case 202 and the cover 203 form a closed space, there is a case where mist is generated inside the cover 203 due to a temperature difference between the inside and the outside of the closed space. During winter, snow sometimes adheres to the outside of the cover 203.

In the present embodiment, since the heater 21 heats the cover 203, it is possible to favorably eliminate the mist inside the cover 203 or favorably melt the snow outside the cover 203.

Further, since the heater 21 is transparent to the laser light used by the laser transceiver 201, it is possible to avoid the situation where the laser light passing through the cover 203 is obstructed by the heater 21.

Since the cover 203 is formed of resin, the amount of absorption of laser light in the cover 203 can be suppressed to a lower degree than when the cover 203 is formed of glass.

(other embodiments)

The above embodiments may be appropriately combined. For example, the above embodiment can be variously modified as follows.

(1) In the -th embodiment, the heater 11 is disposed to extend over turns larger than the field of view v1 of the camera 100 in the front windshield 1, but the heater 11 may be disposed over the entire front windshield 1, whereby fogging of the front windshield 1 can be prevented well, and the heater 11 is transparent, so that it is possible to prevent the heater 11 from obstructing the field of view of the occupant.

(2) In the -th embodiment, the imaging unit 10 and the heater 11 are disposed on the front windshield 1, but the imaging unit 10 and the heater 11 may be disposed on a window other than the front windshield 1, such as a rear windshield.

(3) In the th embodiment, the heater 11 is disposed on the front windshield 1, but the heater 11 may be disposed on a cover for protecting an illumination device (i.e., a device for irradiating visible light) such as a large lamp cover of a vehicle.

(4) Although the carbon nanotubes 111 are used as the heat generating elements of the heater 11 in the -th embodiment, various members that are invisible to the naked eye, such as metal particles, carbon particles, and metal oxide particles, may be used as the heat generating elements of the heater 11.

(5) In the -th embodiment, the image data of the camera 100 is used to prevent a collision of the vehicle, but the present invention is not limited to this, and the image data of the camera 100 may be used for various purposes such as lane departure prevention and vehicle distance measurement.

(6) The camera 100 according to the is a camera for capturing visible light, but may be a camera for capturing infrared light or ultraviolet light.

(7) The laser device 24 for a vehicle of the second embodiment described above transmits or receives laser light toward the front of the vehicle, but may be configured to transmit or receive laser light while rotating the laser transceiver 201 within a horizontal plane in this case, the heater 21 may be provided so as to rotate the heater 21 and the laser transceiver 201 or so that the heater 21 surrounds the laser transceiver 201 by 360 degrees.

(8) In the second embodiment, the heater 21 is used for the laser device 24 for a vehicle, but the heater 21 may be used for a radio wave device for a vehicle. A vehicle radio wave device measures a distance, a direction, an attribute, and the like of an object based on a time from when a radio wave is irradiated to when the radio wave is reflected by the object, and is used as a sensor for automatic driving of a vehicle, for example.

In this case, the mist on the cover of the vehicle radio wave device can be removed by the heater 21, and the influence of moisture generated by the mist on the radio wave can be prevented.

(9) In the second embodiment, the heating element of the heater 21 is the carbon nanotube, but the heating element of the heater 21 may be indium tin oxide, silver mesh, or the like. That is, various members transparent to the laser light used by the laser transceiver 201 may be used.

(10) In the above-described embodiments, the vehicle imaging device and the vehicle laser device have been described as specific examples of the electromagnetic wave utilization system, but the electromagnetic wave utilization system may be a stationary imaging device, a stationary laser device, or the like.