JP6775195B2 - Detection device, detection method and detection program - Google Patents

Description

The present invention relates to a detection device, a detection method, and a detection program for detecting the state of water, the state of freezing, etc. in an object.

Conventionally, a light source that emits light to a road surface (an example of an object), a light detecting means for detecting the intensity of light (an example of a light receiving unit), and a first analyzer that transmits S-polarized light (an example of a polarization separating unit). A road surface condition detection sensor (detection device) including a second detector that transmits P-polarized light (an example of a polarization separation unit) and a signal processing means (an example of a control unit) that processes an output signal from the light detection means. (Example) is disclosed (see, for example, Patent Document 1).

This road surface condition detection sensor identifies the road surface condition based on the relative light intensity between specific wavelengths in P-polarized light.

Japanese Unexamined Patent Publication No. 2005-43240

However, in the conventional detection device, the state of the object is identified based on the relative light intensity between wavelengths by irradiating the object with P polarized light (linearly polarized light), but the object uses polarized light different from the linearly polarized light. There is a desire to accurately detect the state of an object.

Therefore, an object of the present invention is to provide a detection device, a detection method, and a detection program capable of accurately detecting the state of an object.

In order to achieve the above object, the detection device according to one aspect of the present invention directs light in the first wavelength band and light in the second wavelength band, which is less easily absorbed by water than the first wavelength band, toward an object. The polarized light separation unit that separates at least P-polarized light from the light source that emits light and the light that contains S-polarized light and P-polarized light that is reflected or scattered by the object, and the light that is reflected or scattered by the object are polarized. It includes a light receiving unit that receives light through the unit and a control unit that determines the state of the object from information based on the light received by the light receiving unit, and the light emitted from the light source is the S-polarized light and the P-polarized light. substantially uniform randomly polarized der proportion of is, the control unit includes a step S1 polarization intensity in the S-polarized light of the first wavelength band, and P1 polarization intensity in the P-polarized light of the first wavelength band, said first Information based on the S2 polarization intensity in the S polarization in the two wavelength band or the P2 polarization intensity in the P polarization in the second wavelength band is acquired from the light receiving unit, and the S2 polarization intensity or the P2 polarization intensity is a predetermined threshold value. If it is larger than, it is determined that the object is in a snowy state, and the S1 polarization intensity and the S2 polarization intensity are substantially equal to each other, or the P1 polarization intensity and the P2 polarization intensity are substantially equal to each other. When it is determined that the object is in a dry state, the P2 polarization intensity is larger than the S2 polarization intensity, and the value obtained by dividing the S2 polarization intensity by the P2 polarization intensity is equal to or less than a predetermined value. In addition, when it is determined that the object is submerged, the P2 polarization intensity is larger than the S2 polarization intensity, and the intensity at the S2 polarization intensity is divided by the P2 polarization intensity, which is a predetermined value. If it is larger than, it is determined that the object is in a frozen state .

Further, in order to achieve the above object, the detection method according to one aspect of the present invention is a detection method for detecting the state of an object using a detection device, and the control unit is the above-mentioned first wavelength band. S1 polarization intensity in S polarization, P1 polarization intensity in the P polarization in the first wavelength band, S2 polarization intensity in the S polarization in the second wavelength band, or P2 polarization intensity in the P polarization in the second wavelength band. An acquisition step of acquiring information based on the above from the light receiving unit, and a snow accumulation determination step of determining that the object is in a snow accumulation state when the S2 polarization intensity or the P2 polarization intensity is larger than a predetermined threshold value. When the S1 polarization intensity and the S2 polarization intensity are substantially equal to each other, or when the P1 polarization intensity and the P2 polarization intensity are substantially equal to each other, the drying determination step of determining that the object is in a dry state, and the above-mentioned If P2 polarization intensity is greater than the step S2 polarization intensity, and step S2 in polarization intensity, when the value obtained by dividing the P2 polarization intensity is below a predetermined value, determining that the object is a state of flooding Submersion determination step to be performed, and when the P2 polarization intensity is larger than the S2 polarization intensity and the value obtained by dividing the P2 polarization intensity by the intensity at the S2 polarization intensity is larger than a predetermined value, the object is Includes a freeze determination step to determine that is in a frozen state.

Further, in order to achieve the above object, the detection program according to one aspect of the present invention causes a computer to execute a detection method.

It should be noted that these general or specific embodiments may be realized in a system, method, integrated circuit, computer program or recording medium such as a computer-readable CD-ROM, system, method, integrated circuit, computer. It may be realized by any combination of a program and a recording medium.

According to the present invention, the state of an object can be detected with high accuracy.

FIG. 1 is a schematic view showing a detection device according to the first embodiment. FIG. 2 is a flowchart showing the operation of the detection device according to the first embodiment. FIG. 3 is a schematic view showing a vehicle provided with a detection device according to a modified example of the first embodiment. FIG. 4 is a schematic view showing the detection device according to the second embodiment. FIG. 5 is a schematic view showing the detection device according to the second embodiment. FIG. 6 is a schematic view showing a detection device according to a modified example of the second embodiment. FIG. 7 is a flowchart showing the operation of the detection device according to the modified example of the second embodiment. FIG. 8 is a schematic view showing the detection device according to the third embodiment. FIG. 9 is a schematic view showing the detection device according to the fourth embodiment. FIG. 10 is a schematic view showing a detection device according to a modified example of the fourth embodiment. FIG. 11 is a schematic view showing the detection device according to the fifth embodiment. FIG. 12 is a schematic view showing a vehicle provided with the detection device according to the sixth embodiment. FIG. 13 is a block diagram showing a vehicle of the vehicle support system according to the sixth embodiment. FIG. 14 is a schematic view showing the vehicle support system according to the sixth embodiment. FIG. 15 is a schematic view showing a vehicle provided with a detection device according to a modified example of the sixth embodiment. FIG. 16 is a schematic view showing a vehicle provided with the detection device according to the seventh embodiment. FIG. 17A is a schematic view showing the detection device and the wheel according to the seventh embodiment. FIG. 17B is a schematic view showing a detection device and wheels according to a comparative example.

(Knowledge on which the present invention is based)
Currently, there is a demand for a detection device that detects a state such as the amount of water in an object. For example, when an outdoor road surface is used as an object, the road surface has a frozen state, a flooded state, a snow-covered state, and a dry state. The detection device needs to identify these four states.

Water has an absorption spectrum that absorbs light in a unique wavelength region. Therefore, the present inventors have focused on the absorption spectrum of water as a means for detecting the state of the road surface.

Regarding the relationship between the wavelength of light and the absorption coefficient of water, water has peaks that absorb light in the near infrared region of light (called 700 nm to 2500 nm) in the vicinity of 740 nm, 980 nm, 1450 nm, and 1940 nm (referred to as 700 nm to 2500 nm). Absorption peak) is present. In particular, as a property of water, the larger the wavelength of light at the peak of light absorption, the easier it is to absorb light. Therefore, in principle, it is possible to irradiate the road surface with light containing a wavelength near the peak of absorption and detect the presence or absence of water or ice by the amount of the reflected light.

Therefore, for example, when the road surface is submerged, among the light incident on the water surface, S-polarized light has a property of being more likely to be specularly reflected on the water surface than P-polarized light. That is, S-polarized light has a property that the reflectance is more likely to increase than P-polarized light as the incident angle is increased. On the other hand, P-polarized light has a property that it is less likely to be specularly reflected on the water surface than S-polarized light. That is, P-polarized light has a property that the higher the incident angle, the more difficult it is for the reflectance to increase as much as S-polarized light. Therefore, when the P-polarized light is incident on the water surface, it passes through the water and is scattered on the road surface, and a part of the light is directed to the light source side. In such a property of light, for example, when a light receiving unit is arranged on the light source side, the amount of light received by S-polarized light that is specularly reflected is smaller than the amount of light received by P-polarized light that receives light scattered by an object.

Further, when the road surface is in a frozen state, the surface of the ice is rougher than the water surface, so that both S-polarized light and P-polarized light are scattered on the surface as compared with the state where the road surface is flooded. Therefore, when the light receiving portion is arranged on the light source side, there is no significant difference between the light receiving amount of S-polarized light and the light receiving amount of P-polarized light as compared with water. That is, the ratio of the intensity of S-polarized light to the intensity of P-polarized light in scattered light (intensity of S-polarized light / intensity of P-polarized light) is less than 1 in the frozen state, and further in the submerged state than in the frozen state. Therefore, if an appropriate threshold value is set, it becomes possible to distinguish between a submerged state and a frozen state. Therefore, if the road surface is irradiated with random polarized light having a substantially uniform ratio of P-polarized light and S-polarized light in light containing a wavelength near the peak at which water absorbs light, the intensity of scattered light and the P-polarized light and S-polarized light are obtained. It is considered that the road surface condition can be detected by measuring the ratio of.

Further, assuming that the intensity of the scattered light when the road surface is dry is 1, the intensity of the scattered light is larger than 1 in the snowy state. Therefore, it is possible to determine whether the road surface is dry or snowy just by looking at the intensity of the scattered light.

It should be noted that it is not possible to perform accurate detection simply by deriving the light absorbed by the object because it is affected by the surface shape of the object and the absorbing substances other than water. For this reason, it is common to use a method called two-color spectroscopy that suppresses these effects. This is a method of compensating for the influence of the surface shape and absorbing substances other than water by using light having a wavelength of less absorption in addition to the wavelength of the absorption peak that absorbs light. Also in this embodiment, it is preferable to detect the presence of water and ice by using the intensity ratio of the wavelength of the absorption peak that absorbs light and the light of the wavelength that absorbs less light instead of the intensity of scattered light.

In this way, we want to detect the state of the object (presence or absence of water, ice, etc. in the object) by using a different means than the conventional detection device. Further, there is a demand for accurately detecting the state of an object by using polarized light different from the linearly polarized light used in the conventional detection device.

Therefore, it is an object of the present invention to provide a detection device capable of accurately detecting the state of an object.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. Each of the embodiments described below shows a preferred specific example of the present invention. Therefore, the numerical values, shapes, materials, components, arrangement positions of the components, connection forms, and the like shown in the following embodiments are examples and are not intended to limit the present invention. Therefore, among the components in the following embodiments, the components not described in the independent claims indicating the highest level concept of the present invention will be described as arbitrary components.

Further, the description of "abbreviated **" is intended to include not only exactly the same but also substantially the same when explaining by taking "substantially the same" as an example. The same applies to the description of "** neighborhood".

It should be noted that each figure is a schematic view and is not necessarily exactly illustrated. Further, in each figure, the same reference numerals are given to substantially the same configurations, and duplicate description will be omitted or simplified.

(Embodiment 1)
Hereinafter, the detection device according to the first embodiment of the present invention will be described.

[Constitution]
First, the configuration of the detection device 1 according to the present embodiment will be described with reference to FIG.

FIG. 1 is a schematic view showing the detection device 1 according to the first embodiment.

As shown in FIG. 1, the detection device 1 is a device that irradiates an object with light and detects the state of the object. In the present embodiment, the object is, for example, the road surface of a road. The state of the object is a state of snow cover, a state of dryness, a state of flooding, and a state of freezing on the road surface.

The detection device 1 includes a light source 3, a light receiving unit 4, a polarization separating unit 5, a wavelength separating unit 6, a control unit 7, an output unit 8, a power supply unit 9, and a storage unit 11. The light source 3, the light receiving unit 4, the polarization separating unit 5, the wavelength separating unit 6, the control unit 7, the output unit 8, the power supply unit 9, and the storage unit 11 may be provided in a housing (not shown).

The light source 3 is a light emitting module provided so as to emit light toward an object. The light emitted by the light source 3 is random polarized light in which the ratio of S-polarized light and P-polarized light is substantially uniform, and is visible light, infrared light, or the like. Randomly polarized light means that the vibration direction of the electric field in light is random and there are components that oscillate in various directions, and that the components that oscillate randomly are uniform in a unit time. There is.

In the present embodiment, infrared light is used as the light. The S-polarized light is light in the first wavelength band and light in the second wavelength band. Further, P-polarized light is light in the first wavelength band and light in the second wavelength band. Light in the second wavelength band has a wavelength band different from that in the first wavelength band, and has a property of being less easily absorbed by water than the first wavelength band. The light in the first wavelength band and the light in the second wavelength band are wavelength bands near the absorption peak in which water easily absorbs light. In the present embodiment, the light of the light source 3 uses light having a wavelength of λ1 as an example of the first wavelength band and light having a wavelength of λ2 as an example of the second wavelength band.

The infrared light in the first wavelength band is light having an absorption peak having an absorption wavelength at any of 740 nm, 980 nm, 1450 nm, and 1940 nm in water. Further, the infrared light in the second wavelength band is light having a shorter wavelength than the infrared light in the first wavelength band. For example, when the infrared light in the first wavelength band is light in the vicinity of 980 nm, the infrared light in the second wavelength band may be light in the vicinity of 800 nm. When the infrared light in the first wavelength band is light in the vicinity of 1940 nm, the infrared light in the second wavelength band may be light in the vicinity of 1550 nm.

As the light source 3, for example, a light source 3 that emits continuous spectrum light such as a halogen lamp can be used, but the light source 3 is not limited to this. For example, the light source 3 may be an LED (Light Emitting Diode) element, a semiconductor light emitting element such as a semiconductor laser, or another solid light emitting element such as an EL element such as an organic EL (Electroluminescence) or an inorganic EL.

The light receiving unit 4 is provided so as to face the object so that the irradiated light receives the light scattered by the object. That is, the light receiving unit 4 is provided on the light source 3 side, and is not arranged so that the light of the light source 3 receives the light that is specularly reflected by the object. The light receiving unit 4 generates information regarding the amount of light received. The light receiving unit 4 is, for example, an optical sensor such as an infrared sensor, but may be a camera.

Specifically, the light receiving unit 4 generates information P1, information P2, and information S1 as information regarding the amount of light, and transmits the information to the control unit 7. The information P1 is information based on light of P polarization and P1 polarization intensity at wavelength λ1 that has passed through the P polarization filter 51 and the first wavelength separation filter 61. The information P2 is information based on light having P polarization and P2 polarization intensity at wavelength λ2, which has passed through the P polarization filter 51 and the second wavelength separation filter 62. The information S1 is information based on light having S polarization and S1 polarization intensity at wavelength λ1 that has passed through the S polarization filter 52 and the first wavelength separation filter 61. The information S2 described later is information based on light having S polarization and S2 polarization intensity at wavelength λ2 that has passed through the S polarization filter 52 and the second wavelength separation filter 62. In the present embodiment, the light having a wavelength λ1 is a wavelength that is more easily absorbed by water than the light having a wavelength λ2. That is, at the absorption peak where water absorbs light, the wavelength λ1 has a wavelength larger than the wavelength λ2. The wavelength λ1 is light in the vicinity of the wavelength λ1. The same applies to the wavelength λ2.

The polarization separating unit 5 is provided between the object and the light receiving unit 4, and has a function of separating a predetermined polarized light from the light scattered by the object. The polarizing separator 5 is, for example, a polarizing filter, a polarizing beam splitter, or the like.

The polarizing separation unit 5 has a P polarizing filter 51 and an S polarizing filter 52. The P-polarizing filter 51 has a property of transmitting P-polarized light. The S polarization filter 52 has a property of transmitting S-polarized light. The P polarizing filter 51 and the S polarizing filter 52 are provided so as to exchange their positions with each other by a drive unit (not shown).

The wavelength separation unit 6 has a function of separating wavelengths that transmit only light in a predetermined wavelength region. In the present embodiment, the wavelength separation unit 6 is provided between the polarization separation unit 5 and the light receiving unit 4, but may be provided between the object and the polarization separation unit 5.

The wavelength separation unit 6 includes a first wavelength separation filter 61 and a second wavelength separation filter 62. The first wavelength separation filter 61 has a function of transmitting light in the vicinity of the wavelength λ1. The second wavelength separation filter 62 has a function of transmitting light in the vicinity of the wavelength λ2. The first wavelength separation filter 61 and the second wavelength separation filter 62 are also provided so as to exchange positions with each other by a drive unit (not shown).

The control unit 7 is electrically connected to the light receiving unit 4, the light source 3, the output unit 8, the power supply unit 9, and the like. The control unit 7 receives information regarding the amount of light received by the light receiving unit 4. The control unit 7 may adjust the output of light in the light source 3 from the information regarding the amount of light.

The control unit 7 includes a determination unit 71 and a power supply control unit 72.

The determination unit 71 determines the snow state, the dry state, the flooded state, and the frozen state of the object based on the information P1, the information P2, and the information S1 received via the control unit 7. The power supply control unit 72 controls the light source 3 to emit light.

The power supply unit 9 may be, for example, not only the power supply supplied from the primary battery or the secondary battery, but also the power supply supplied from the power system. The power supply unit 9 is connected to the control unit 7 and supplies electric power to each unit such as the output unit 8 and the light source 3 via the control unit 7.

The output unit 8 is, for example, a monitor such as a liquid crystal display, an LED display, or an organic EL display, a speaker that outputs sound or the like, or the like. The output unit 8 outputs the state of the object determined by the determination unit 71. Specifically, the output unit 8 outputs information such as a snow cover state, a dry state, a flooded state, and a frozen state in the object determined by the determination unit 71.

The storage unit 11 is a device that stores a control program executed by the control unit 7 when the control unit 7 includes a processor, a microcomputer, or the like. The storage unit 11 is realized by, for example, a semiconductor memory. The storage unit 11 may store past information regarding the snow-covered state, the dry state, the flooded state, and the frozen state of the past object.

A method for determining a snow-covered state, a dry state, a flooded state, and a frozen state in such a detection device 1 will be described.

The state of snow cover on the object can be determined by whether or not the reflectance of the information P2 is equal to or greater than the threshold value. This threshold value is calculated based on the reflectance when the road surface is irradiated with light on asphalt, concrete, white line, yellow line, and snow when the object is the road surface. The reflectance of each is about 0.11 for asphalt, about 0.42 for concrete, about 0.63 for the white line, about 0.52 for the yellow line, and about 0.9 for snow cover. is there. From this result, in the present embodiment, the threshold value, which is a value between the reflectance of the white line having the highest reflectance other than snow cover and the reflectance of snow cover, is set to 0.8. Note that this threshold value is an example and is not particularly limited as long as it is between a snow-covered state and an object having the highest reflectance other than the snow-covered state. The determination unit 71 determines whether or not the road surface is in a snowy state depending on whether or not the information P2 is larger than the threshold value.

The dry state of the object can be determined by whether or not the information P1 and the information P2 are similar to each other. This is because when substantially uniform random polarized light is incident on a dry object, the same amount of light having a wavelength λ1 and light having a wavelength λ2 are absorbed by the object. Therefore, in the scattered light of the object, the light amount of the wavelength λ1 and the light amount of the wavelength λ2 are substantially the same. Further, in the present embodiment, the fact that the information P1 and the information P2 are similar means that the error between the information P1 and the information P2 is within ± 20%. For example, when the object is a road surface, it is preferable to have this error range because it differs depending on the material of the road surface.

In the present embodiment, the state of flooding in the object is determined by whether or not the S2 polarization intensity (information S2) / P2 polarization intensity (information P2) is equal to or less than a predetermined value. This is because when light having a wavelength of λ2 is incident on water, S-polarized light has a higher reflectance than P-polarized light, so that reflected light scattered by water contains more P-polarized light than S-polarized light. Here, the S2 polarization intensity (information S2) / P2 polarization intensity (information P2) is smaller than 1 in both the frozen state and the submerged state, but the submerged state is further smaller than the frozen state. That is, the S2 polarization intensity (information S2) / P2 polarization intensity (information P2) is the ratio of the S polarization of the wavelength λ2 to the P polarization of the wavelength λ2 (the value obtained by dividing the intensity at the S2 polarization intensity by the P2 polarization intensity). .. Therefore, in order to determine the state of flooding and the state of freezing, for example, it can be determined whether or not the S2 polarization intensity (information S2) / P2 polarization intensity (information P2) is a predetermined value or less. In the present embodiment, the predetermined value is 0.9. In order to determine the flooded state and the frozen state, for example, it may be determined whether or not the S1 polarization intensity (information S1) / P1 polarization intensity (information P1) is equal to or less than a predetermined value. Good.

The frozen state of the object is determined when the S2 polarization intensity (information S2) / P2 polarization intensity (information P2) is 1 or less and greater than 0.9 by the method of determining the state of flooding.

[Operation of detection device]
Next, an operation in the detection device 1, a detection method using the detection device 1, and an example of a detection program for causing a computer to execute the detection method will be described with reference to FIG.

FIG. 2 is a flowchart showing the operation of the detection device 1 according to the first embodiment.

As shown in FIG. 2, for example, when light of P1 polarization intensity is received by the light receiving unit 4, the control unit 7 receives a P polarization filter 51 and a first wavelength separation filter 61 between the light receiving unit 4 and the object. It is arranged by the drive unit so that and is located. Then, the control unit 7 emits light from the light source 3 to irradiate the object with light (step S1). The light radiated to the object is scattered, and a part of the light is directed to the light receiving unit 4. Then, this light passes through the P polarizing filter 51 and the first wavelength separation filter 61 to become light having P1 polarization intensity, and is received by the light receiving unit 4. The light receiving unit 4 generates information P1 regarding the amount of received light, and transmits the information P1 to the control unit 7 (step S2).

Next, the control unit 7 receives the information P1 from the light receiving unit 4 (an example of the acquisition step), and stores the information P1 in the storage unit 11 (step S3).

Next, when the light receiving unit 4 receives light of S2 polarization intensity, the control unit 7 arranges that the S polarization filter 52 and the second wavelength separation filter 62 are located between the light receiving unit 4 and the object. , Arranged by the drive unit. Then, the light scattered by the object and directed to the light receiving unit 4 passes through the S polarizing filter 52 and the second wavelength separation filter 62 to become light having S2 polarization intensity, and is received by the light receiving unit 4. The light receiving unit 4 generates information S2 regarding the amount of received light, and transmits the information S2 to the control unit 7 (step S4).

Next, the control unit 7 receives the information S2 from the light receiving unit 4 (an example of the acquisition step), and stores the information S2 in the storage unit 11 (step S5).

Next, when the light receiving unit 4 receives light of P2 polarization intensity, the control unit 7 arranges that the P polarization filter 51 and the second wavelength separation filter 62 are located between the light receiving unit 4 and the object. , Arranged by the drive unit. Then, the light scattered by the object and directed to the light receiving unit 4 passes through the P polarizing filter 51 and the second wavelength separation filter 62 to become light having P2 polarization intensity, and is received by the light receiving unit 4. The light receiving unit 4 generates information P2 regarding the amount of received light, and transmits the information P2 to the control unit 7 (step S6).

Next, the control unit 7 receives the information P2 from the light receiving unit 4 and stores the information P2 in the storage unit 11 (step S7).

Next, the determination unit 71 of the control unit 7 determines whether or not the information P2 is larger than a predetermined threshold value (step S8). When the information P2 is larger than the threshold value (YES in step S8), the determination unit 71 determines that the state of the object is the snow cover state (step S13: an example of the snow cover determination step). The control unit 7 outputs to the output unit 8 the content that the determination unit 71 has determined that it is in a snowy state (step S12). In this way, this flow returns to the start and performs the same detection.

In step S8, it may be determined whether or not the information S2 is larger than the predetermined threshold value instead of the information P2. In this case, light having S-polarized light and S2 polarization intensity having a wavelength λ2 is taken out by passing through the S-polarizing filter 52 and the second wavelength separation filter 62, and in step S6, the light receiving unit 4 receives information S2 regarding the amount of received light. It may be generated and the information S2 may be transmitted to the control unit 7. Further, in step S7, the control unit 7 may receive the information S2 from the light receiving unit 4 and store the information S2 in the storage unit 11.

On the other hand, when the information P2 is equal to or less than the threshold value (NO in step S8), the determination unit 71 determines whether or not the information P1 and the information P2 are close to each other (step S9). In step S9, it may be determined whether or not the information S1 and the information S2 are similar to each other.

Specifically, when the error between the information P1 and the information P2 is within ± 20% (YES in step S9), the determination unit 71 determines that the information P1 and the information P2 are close to each other. It is determined that the state of the object is a dry state (step S14: an example of the drying determination step). In this case, the control unit 7 outputs to the output unit 8 the content that the determination unit 71 has determined that the state is dry (step S12). In this way, this flow returns to the start and performs the same detection.

On the other hand, when the error between the information P1 and the information P2 is not within ± 20% (NO in step S9), the determination unit 71 has S polarization (information S2) / P polarization (information P2) of a predetermined value or less. It is determined whether or not it is in a state (step S10). In step S10, light having a wavelength of λ1 may be used, but light having a wavelength of λ2 is less likely to be absorbed by water than light having a wavelength of λ1, and the intensity of the light returning to the light receiving unit 4 is high. It is preferable to use light having a wavelength of λ2 because it becomes large and less susceptible to noise.

Specifically, when the S polarization (information S2) / P polarization (information P2) is equal to or less than a predetermined value (0.9 in the present embodiment) (YES in step S10), the determination unit 71 determines the state of the object. Is in a flooded state (step S15: an example of a flooded determination step). Then, the control unit 7 outputs to the output unit 8 the content that the state of flooding is determined by the determination unit 71 (step S12). In this way, this flow returns to the start and performs the same detection.

In step S9, the magnitude of the information P1 and the information P2 is determined, and if the information P1 is smaller than the value obtained by multiplying the information P2 by 100% -20%, the control unit 7 has a low reflectance in water. From the information P1 which is polarized light and is light having a wavelength λ1 which is easily absorbed by water, it may be determined that water exists in the object, or it may be determined that water may exist.

On the other hand, when the S polarization (information S2) / P polarization (information P2) is larger than the predetermined value (0.9 in the present embodiment) (NO in step S10), the determination unit 71 freezes the state of the object. (Step S11: An example of the freezing determination step). Then, the control unit 7 outputs to the output unit 8 the content that the determination unit 71 is in the frozen state (step S12). In this way, this flow returns to the start and performs the same detection.

[Action and effect of embodiment 1]
Next, the operation and effect of the detection device 1, the detection method, and the detection program in the present embodiment will be described.

As described above, the detection device 1 according to the present embodiment includes light having a wavelength λ1 in the first wavelength band and light having a wavelength λ2 in the second wavelength band that is less likely to be absorbed by water than the wavelength λ1 in the first wavelength band. A light source 3 that emits light toward an object, a polarization separator 5 that separates at least P-polarized light from light that is reflected or scattered by the object and contains S-polarized light and P-polarized light, and light that is reflected or scattered by the object. A light receiving unit 4 that receives light via the polarization separating unit 5 and a control unit 7 that determines the state of an object from information based on the light received by the light receiving unit 4 are provided. The light emitted from the light source 3 is randomly polarized light having a substantially uniform ratio of S-polarized light and P-polarized light.

According to this configuration, the control unit can determine the state of the object by combining the light having the wavelength λ1 in the first wavelength band and the light having the wavelength λ2 in the second wavelength band with S-polarized light and P-polarized light. it can.

Therefore, this detection device can accurately detect the state of the object by using polarized light different from the case of detecting the state of the object using linearly polarized light.

Further, in the detection device 1 according to the present embodiment, the determination unit 71 of the control unit 7 determines the S1 polarization intensity in the S polarization of the wavelength λ1 in the first wavelength band and the P1 in the P polarization of the wavelength λ1 in the first wavelength band. Information based on the polarization intensity and the S2 polarization intensity in the S polarization of the wavelength λ2 in the second wavelength band or the P2 polarization intensity in the P polarization of the wavelength λ2 in the second wavelength band is acquired from the light receiving unit 4. Further, the determination unit 71 of the control unit 7 determines that the object is in a snow-covered state when the S2 polarization intensity or the P2 polarization intensity is larger than a predetermined threshold value. Further, the determination unit 71 of the control unit 7 determines that the object is in a dry state when the S1 polarization intensity and the S2 polarization intensity are substantially equal to each other or when the P1 polarization intensity and the P2 polarization intensity are substantially equal to each other. The control unit 7, when P2 polarization intensity is greater than S2 polarization intensity, and to S2 polarization intensity, when the value obtained by dividing the P2 polarization intensity is below a predetermined value, the object is in a state of flooding Judge that there is. Then, the determination unit 71 of the control unit 7 determines the object when the P2 polarization intensity is larger than the S2 polarization intensity and when the value obtained by dividing the P2 polarization intensity by the intensity in the S2 polarization intensity is larger than the predetermined value. Is determined to be in a frozen state.

According to this configuration, the light receiving unit 4 can generate information P1, information P2, information S1 and information S2 from the combination of P-polarized light and S-polarized light and light having wavelength λ1 and wavelength λ2. The determination unit 71 can determine the snow-covered state, the dry state, the flooded state, and the frozen state of the object from the received information (information P1, information P2, information S1 and information S2). Therefore, the state of the object can be reliably detected.

Further, in the detection device 1 according to the present embodiment, between the object and the light receiving unit 4, the light reflected or scattered by the object, the light having the wavelength λ1 in the first wavelength band, and the second light. A wavelength separation unit 6 for separating light having a wavelength λ2 in the wavelength band is provided.

According to this configuration, light having a desired wavelength can be extracted from the light emitted by the light source 3. Therefore, it is not necessary to prepare a light source 3 that emits light having a desired wavelength, and it is possible to suppress an increase in manufacturing cost.

Further, in the detection device 1 according to the present embodiment, the light emitted by the light source 3 is infrared light. The infrared light having a wavelength of λ1 in the first wavelength band is light having an absorption peak having an absorption wavelength at any of the vicinity of 740 nm, the vicinity of 980 nm, the vicinity of 1450 nm, and the vicinity of 1940 nm in water. The infrared light having a wavelength λ2 in the second wavelength band is light having a shorter wavelength than the infrared light having a wavelength λ1 in the first wavelength band.

According to this configuration, for example, if light in the vicinity of 1940 nm is selected as the wavelength λ1, the water absorption is high, so that the sensor has high sensitivity. Further, if light in the vicinity of 980 nm is selected as the wavelength λ1, there is an advantage that a silicon photodetector can be used.

Further, in the detection method according to the present embodiment, the state of the object is detected by using the detection device 1. Further, the determination unit 71 of the control unit 7 determines the S1 polarization intensity in the S polarization of the wavelength λ1 in the first wavelength band, the P1 polarization intensity in the P polarization of the wavelength λ1 in the first wavelength band, and the wavelength λ2 in the second wavelength band. The acquisition step of acquiring information based on the S2 polarization intensity in the S polarization or the P2 polarization intensity in the P polarization of the wavelength λ2 in the second wavelength band from the light receiving unit 4, and the S2 polarization intensity or the P2 polarization intensity is greater than a predetermined threshold value. When the size is large, the object is determined to be in a snowy state, and the S1 polarization intensity and the S2 polarization intensity are substantially equal to each other, or the P1 polarization intensity and the P2 polarization intensity are approximately equal to each other. and drying determination step of determining that the state of the drying, if P2 polarization intensity is greater than S2 polarization intensity, and to S2 polarization intensity, when the value obtained by dividing the P2 polarization intensity is below a predetermined value, the target A submergence determination step for determining that an object is submerged, and a case where the P2 polarization intensity is greater than the S2 polarization intensity and the value obtained by dividing the P2 polarization intensity by the intensity at the S2 polarization intensity is greater than a predetermined value. Including a freezing determination step of determining that the object is in a frozen state.

This detection method also has the same effect as that of the detection device 1 according to the present embodiment.

Further, the detection program according to the present embodiment causes the computer to execute the detection method.

This detection program also has the same effect as the detection device 1 according to the present embodiment.

(Modified Example of Embodiment 1)
Hereinafter, the detection device 1 according to the present modification of the first embodiment will be described with reference to FIG.

FIG. 3 is a schematic view showing a vehicle 110 provided with a detection device 1 according to a modification of the first embodiment.

This modification of the first embodiment is different from the first embodiment in that the camera 140 is used as an example of the light receiving unit 4.

Other configurations in the present modification of the first embodiment are the same as those in the first embodiment, and the same configurations are designated by the same reference numerals and detailed description of the configurations will be omitted.

As shown in FIG. 3, in the present modification of the first embodiment, the detection device 1 is provided in the vehicle 110. The vehicle 110 includes a vehicle body 111, wheels 112, a steering wheel 113, a steering angle detection unit 114, and a speed detection unit 115.

The vehicle body 111 is provided with wheels 112, a steering wheel 113, a steering angle detection unit 114, a speed detection unit 115, and the like. The wheels 112 are steered by the handle 113. The steering angle detection unit 114 is a sensor that detects the steering angle of the wheel 112, and is, for example, a steering angle sensor that measures a relative angle change amount. The steering angle detection unit 114 detects the steering angle of the wheel 112 and transmits the detected steering angle information (an example of the first information) to the control unit 7. The speed detection unit 115 is a sensor that detects the traveling speed of the vehicle 110, and is, for example, a speed detection sensor or the like. The speed detection unit 115 detects the traveling speed of the vehicle 110 and transmits the detected speed information (an example of the second information) to the control unit 7.

When the light source 3 emits infrared light, the camera 140 generates a first image (an example of information) of an image of an object and transmits it to the control unit 7. In this first image, the state of snow cover, the state of dryness, the state of flooding, and the state of freezing, which are the states of the object, are reflected. The object in this modification of the first embodiment is, for example, a road surface, a radiator grill of an automobile, or the like.

Further, when the light source 3 emits visible light, the camera 140 generates a second image (an example of information) of an image of the object and transmits it to the control unit 7. This second image is a normal image of the object.

The control unit 7 generates a third image received from the camera 140 and superimposed on the first image, and causes the output unit 8 to output the third image. That is, the output unit 8 outputs an image of the object to which the snow-covered state, the dry state, the flooded state, and the frozen state are added.

Further, the camera 140 generates a fourth image showing the distance between the object and the camera 140, and transmits the fourth image to the control unit 7. This fourth image is an image having distance information.

The control unit 7 generates a fifth image in which the fourth image received from the camera 140 is superimposed on the third image, and outputs the fifth image to the output unit 8. That is, in the output unit 8, information indicating the distance between the object and the camera 140 is added to the image of the object to which the snow state, the dry state, the flooded state, and the frozen state are added. The image is output. The first to fifth images may be still images or moving images.

Further, the control unit 7 changes the position where the object is imaged according to the steering angle information of the wheels 112 and the speed information of the vehicle 110. For example, the light source 3 may be provided so as to be swingable so that the optical axis direction (direction in which light is emitted) of the light source 3 can be changed. The means for swinging the light source 3 can be realized by a drive mechanism. Further, in this case, the drive mechanism may be configured to change the postures of the camera 140, the polarization separation unit 5, and the wavelength separation unit 6 (the camera 140 changes the position to be imaged).

As an example of changing the position for photographing an object, the control unit 7 is the traveling direction of the vehicle 110 detected by the steering angle detecting unit 114 from the steering angle of the wheels 112 as the steering angle of the wheels 112 increases. , The camera 140 is made to take an image of an object far from the detection device 1. Further, the control unit 7 causes the camera 140 to take an image of an object far from the detection device 1 as the traveling speed of the vehicle 110 increases. If the steering angle becomes large or the traveling speed of the vehicle 110 becomes high, the passenger (user) of the vehicle 110 may want to grasp the state of the object at a greater distance. In addition to the steering angle, the camera 140 may image an object far from the detection device 1 according to the rate of increase in the steering angle (angular velocity of the steering angle).

Further, as an example of imaging a distant object, for example, the optical axis from the light source 3 currently being irradiated so as to bring the optical axis direction of the light source 3 irradiated during the current traveling of the vehicle 110 closer to horizontal. The light of the light source 3 is irradiated toward the object farther than the distance to the upper object.

Also in this detection device 1, the same operation as the flowchart shown in FIG. 2 is performed.

[Action effect]
Next, the operation and effect of the detection device 1 in the present modification of the first embodiment will be described.

As described above, the detection device 1 according to the present modification of the first embodiment further includes an output unit 8 that outputs the state of the object. Further, the light source 3 emits infrared light and visible light. Then, the camera 140 generates a first image in which the object is imaged when the light source emits infrared light and a second image in which the object is imaged when the light source emits visible light. It is transmitted to the determination unit 71 of the control unit 7. Then, the determination unit 71 of the control unit 7 generates a third image in which the first image is superimposed on the second image received from the camera 140, and outputs the third image to the output unit 8.

According to these configurations, a third image in which the state of the object is added to the normal image of the object is output to the output unit 8, so that information that is easy for the passenger to understand can be provided. Therefore, since the passenger can immediately recognize and determine the state of the object, it is easy to avoid danger in the vehicle 110.

Further, in the detection device 1 according to the present modification of the first embodiment, the camera 140 generates a fourth image showing the distance between the object and the camera 140 in the second image, and causes the determination unit 71 of the control unit 7 to generate a fourth image. Send. The determination unit 71 of the control unit 7 generates a fifth image in which the fourth image received from the camera 140 is superimposed on the third image, and outputs the fifth image to the output unit 8.

According to this configuration, since the fifth image in which the distance information is added to the third image is output to the output unit 8, it is possible to provide information that is easy for the passenger to understand. Therefore, since the passenger can more immediately recognize and judge the state of the object, it is easier to avoid danger in the vehicle 110.

Further, the detection device 1 according to the present modification of the first embodiment is mounted on the vehicle 110. Further, the vehicle 110 has a wheel 112 that is steered by the steering wheel 113, a steering angle detection unit 114 that detects the steering angle of the wheel 112, and a speed detection unit 115 that detects the traveling speed of the vehicle 110. Further, the steering angle detection unit 114 transmits the first information regarding the steering angle of the wheels 112 to the control unit 7. Further, the speed detection unit 115 transmits the second information regarding the traveling speed of the vehicle 110 to the control unit 7. Then, the control unit 7 controls so as to change the irradiation direction of the light source 3 and the position at which the object is imaged according to the first information and the second information.

According to this configuration, the direction in which the control unit 7 irradiates light and the position in which the object is imaged are changed according to the traveling speed of the vehicle 110 and the steering angle of the steering wheel 113, so that the appropriate position in the object is determined. The state can be detected.

Further, in the detection device 1 according to the present modification of the first embodiment, the control unit 7 advances the vehicle 110 detected by the steering angle detection unit 114 from the steering angle of the wheels 112 as the steering angle of the wheels 112 increases. The camera 140 is made to take an image of an object that is in the direction and is far from the detection device 1.

According to this configuration, when the steering angle of the wheel 112 is large, a distant object is imaged, so that information that is easy for the passenger to understand can be provided. Therefore, the passenger can easily recognize the state of the object.

Further, in the detection device 1 according to the present modification of the first embodiment, the control unit 7 causes the camera 140 to take an image of an object farther from the detection device 1 as the traveling speed of the vehicle 110 increases.

According to this configuration, when the traveling speed of the vehicle 110 is high, a distant object is imaged, so that information that is easy for the passenger to understand can be provided. Therefore, the passenger can easily recognize the state of the object.

The other effects of the present modification of the first embodiment also have the same effects as those of the first embodiment.

(Embodiment 2)
Hereinafter, the detection device 200 according to the present embodiment will be described.

[Constitution]
The configuration of the detection device 200 according to the present embodiment will be described with reference to FIG.

FIG. 4 is a schematic view showing the detection device 200 according to the second embodiment.

In the first embodiment, one light source 3 is provided, but the detection device 200 in the present embodiment is different in that two light sources 3 are provided. Further, although one light receiving unit 4 is provided in the first embodiment, the detection device 200 in the present embodiment is different in that the first light receiving unit 41 and the second light receiving unit 42 are provided. Further, the present embodiment is different in that the wavelength separation unit 6 as in the first embodiment is not provided.

The other configurations in the present embodiment are the same as those in the first embodiment, and the same configurations are designated by the same reference numerals and detailed description of the configurations will be omitted.

As shown in FIG. 4, in addition to the control unit 7 and the polarization separating unit 5, the detection device 200 includes a first light source 31, a second light source 32, a first light receiving unit 41, and a second light receiving unit 42. Have. In the present embodiment, the polarization separating unit 5 is a polarization beam splitter capable of separating S-polarized light and P-polarized light.

The light emitted by the first light source 31 is random polarized light in which the ratio of S-polarized light and P-polarized light is substantially uniform, and is light in the first wavelength band. In the present embodiment, the wavelength of the first wavelength band is λ1. The light emitted by the second light source 32 is random polarized light in which the ratio of S-polarized light and P-polarized light is substantially uniform, and is light in the second wavelength band. In the present embodiment, the wavelength of the second wavelength band is λ2. The first light source 31 and the second light source 32 are provided so that their respective optical axes intersect with the object. The first light source 31 and the second light source 32 may be the same light source 3 as in the first embodiment.

The first light receiving unit 41 receives S-polarized light among the light separated by the polarization separating unit 5. The second light receiving unit 42 receives P-polarized light among the light separated by the polarization separating unit 5. The first light receiving unit 41 and the second light receiving unit 42 transmit information based on the received light to the control unit 7.

The power supply control unit 72 of the control unit 7 controls the first light source 31 to emit light having a wavelength λ1 and controls the second light source 32 to emit light having a wavelength λ1. The power supply control unit 72 controls so that the first light source 31 and the second light source 32 are alternately turned on and off.

FIG. 5 is a schematic view showing the detection device 200 according to the second embodiment. As shown in FIG. 5, the polarizing separation unit 5 may be the S polarizing filter 52 and the P polarizing filter 51 similar to those in the first embodiment. In this case, one light receiving unit 4 may be used as in the first embodiment.

Also in this detection device 200, the same operation as the flowchart shown in FIG. 2 is performed.

[Action effect]
Next, the operation and effect of the detection device 200 in the present embodiment will be described.

As described above, in the detection device 200 according to the present embodiment, the light source 3 emits the light of the wavelength λ1 of the first wavelength band and the light of the wavelength λ2 of the second wavelength band. It has a second light source 32. Then, the control unit 7 controls so that the first light source 31 and the second light source 32 are alternately turned on and off.

According to this configuration, since the first light source 31 emits light having a wavelength λ1 and the second light source 32 emits light having a wavelength λ2, the wavelength separation unit 6 is not required as in the first embodiment. Therefore, it is possible to receive the light of the wavelength λ1 and the wavelength λ2, respectively, through the object without providing the configuration for separating the wavelength from the light of the light source 3. Therefore, it is possible to suppress the increase in size of the detection device 200.

The other effects of the present embodiment also have the same effects as those of the first embodiment.

(Modified Example of Embodiment 2)
Hereinafter, the detection device 200 according to the present modification of the second embodiment will be described with reference to FIG.

FIG. 6 is a schematic view showing a detection device 200 according to a modified example of the second embodiment.

In the second embodiment, as in the first embodiment, the light receiving unit 4 is provided so as to face the object on the light source 3 side so that the irradiated light receives the light scattered by the object. As shown in 6, in the present modification of the second embodiment, the light receiving unit 4 is different in that the light receiving unit 4 is provided so as to receive the light that is specularly reflected by the object. Further, in the second embodiment, the P-polarized light and the S-polarized light are separated by the polarizing separation unit 5, but in the present modification of the second embodiment, the polarization separation unit 5 uses only the P polarization filter 51. .. That is, the polarization separating unit 5 separates at least P-polarized light from light containing S-polarized light and P-polarized light.

In the present modification of the second embodiment, the detection device 200 is most suitable for detecting the water content of the skin to roughly know the water content of the stratum corneum (about 10 μm to 20 μm) in the skin. The state of the skin (moisturizing state, dry state, rough skin, etc.) can be detected by the amount of water in the stratum corneum. That is, the condition of the skin can be detected by the amount of water in the relatively shallow part of the skin. Therefore, in this embodiment, only P-polarized light is used.

Other configurations in the present modification of the second embodiment are the same as those in the first embodiment and the like, and the same configurations are designated by the same reference numerals and detailed description of the configurations will be omitted.

As shown in FIG. 6, the control unit 7 calculates an index A that correlates with the water content from the information P1 and the information P2 using the equation 1 (viewed by near-infrared spectroscopic image by Mutsuko Nakamura and Shigeki Nakauchi). Moisturizing effect of cosmetics "Optical, 2010, Vol. 39, No. 11, P529-P533).

Here, the index A is an index indicating that the index A becomes 0 when the object is dry, and becomes larger than 0 as the amount of water contained in the object increases.

The control unit 7 calculates the water content of the object from the calculated index A according to the calculation formula or table stored in the storage unit 11. For example, the calculation formula or table may be a calibration curve derived from the light amount ratio between the skin and the water content.

The detection device 200 can detect the amount of water in the skin (the state of water in the skin) by wearing it on the body. In this case, the skin of the human body is the object. In the detection device 200, the light receiving unit 4 receives the light reflected by the skin (the surface of the skin and the inside of the skin), and the control unit 7 determines the water content of the skin from the intensity of the light obtained through the light receiving unit 4. calculate.

The light incident on the skin includes light reflected on the surface of the skin and light incident on the inside of the skin (about 10 μm to about 20 μm) and scattered. Most of the light scattered inside the skin is emitted in a direction different from the direction in which the light reflected on the surface of the skin is specularly reflected. Further, since P-polarized light is received among the light reflected by the skin, the reflection on the surface of the skin is reduced. Therefore, the detection device 200 can detect only the amount of water in the skin by receiving the reflected light that has entered a little from the surface of the skin to the inside.

In addition, in detecting the state of the skin, P-polarized light is used, but this is not indispensable, and S-polarized light may be used. Further, it is sufficient to detect the water content in the state of the object, and it is not essential to detect the frozen state.

[Operation of detection device]
Next, an example of the operation in the detection device 200 will be described with reference to FIG. 7.

FIG. 7 is a flowchart showing the operation of the detection device 200 according to the modified example of the second embodiment.

As shown in FIG. 7, first, the user wears the detection device 200 on the body in order to detect the amount of water in the skin. Then, the dedicated program stored in the detection device 200 is started.

For example, when the light receiving unit 4 receives light having a P1 polarization intensity, the control unit 7 emits light having a wavelength of λ1 from the first light source 31, so that the skin is irradiated with light (step S21). The light radiated to the skin is scattered, and a part of the light is directed to the P polarizing filter 51 side. Then, this light passes through the P polarizing filter 51, becomes light having P1 polarization intensity, and is received by the light receiving unit 4. The light receiving unit 4 generates information P1 regarding the amount of received light, and transmits the information P1 to the control unit 7 (step S22). Then, the control unit 7 turns off the first light source 31.

Next, the control unit 7 receives the information P1 from the light receiving unit 4 and stores the information P1 in the storage unit 11 (step S23).

Next, when the light receiving unit 4 receives the light having the P2 polarization intensity, the control unit 7 emits the light having the wavelength λ2 from the second light source 32, so that the skin is irradiated with the light (step S24). The light radiated to the skin is scattered, and a part of the light is directed to the P polarizing filter 51 side. Then, this light passes through the P polarizing filter 51, becomes light having P2 polarization intensity, and is received by the light receiving unit 4. The light receiving unit 4 generates information P2 regarding the amount of received light, and transmits the information P2 to the control unit 7 (step S25). Then, the control unit 7 turns off the second light source 32.

Next, the control unit 7 receives the information P2 from the light receiving unit 4 and stores the information P2 in the storage unit 11 (step S26).

Next, the control unit 7 calculates an index A correlating with the water content from the information P1 and the information P2 using the equation 1 (step S27). If the outputs of the first light source 31 and the second light source 32 are adjusted in advance so that the information P1 and the information P2 are equal, the index A becomes 0 when the object is in a dry state, and the target. It becomes larger than 0 as the water content of the object increases.

Next, the control unit 7 calculates the amount of water from the calculated index A according to the calculation formula or table stored in the storage unit 11 (step S28).

Next, the control unit 7 causes the output unit 8 to output the amount of water obtained in step S28 (step S29). In this way, this flow returns to the start and continues to perform the same detection.

The other effects of the present modification of the second embodiment also have the same effects as those of the first embodiment.

(Embodiment 3)
Hereinafter, the detection device 300 according to the present embodiment will be described.

[Constitution]
The configuration of the detection device 300 according to the present embodiment will be described with reference to FIG.

FIG. 8 is a schematic view showing the detection device 300 according to the third embodiment.

In the second embodiment, the light from the light source 3 is directly irradiated to the object, but in the present embodiment, the object is irradiated with the light through the scanning mirror 310 (an example of the reflector).

Further, the present embodiment is different from the modified example of the second embodiment in that a scattering plate 150 for scattering the incident light is provided between the camera 140 and the P polarizing filter 51.

As in the modified example of the second embodiment, the camera 140 is provided so that the irradiated light receives the light that is specularly reflected by the object. In this embodiment, the camera 140 is used as an example of the light receiving unit 4.

The other configurations in the present embodiment are the same as those in the first embodiment, and the same configurations are designated by the same reference numerals and detailed description of the configurations will be omitted.

As shown in FIG. 8, the scanning mirror 310 is a swingable mirror so as to distribute the light from the light source 3 to different places of the object. As the scanning mirror 310, for example, a mirror in which two galvano mirrors are combined may be used. Specifically, when light is emitted from the first light source 31, the control unit 7 reflects the light from the light source 3 while swinging the scanning mirror 310 to scan the light to irradiate the object. .. The swing of the scanning mirror 310 is performed by the swing portion 311 having a drive mechanism. In this scanning of light, the scanning mirror 310 swings so as to irradiate a predetermined range of the object.

In the present embodiment, the scanning mirror 310 is oscillated, but the first light source 31 and the second light source 32 may be oscillated.

An ND (Neutral Density) filter may be provided between the scattering plate 150 and the light receiving unit 4. Then, the camera 140 may receive the light that has passed through the scattering plate 150 and the ND filter.

In this detection device 300, the light emitted from the first light source 31 and the second light source 32 is reflected by the scanning mirror 310 and scattered by the object, and is received by the camera 140 through the P polarizing filter 51 and the scattering plate 150. To. Specifically, in the light reflected by the object through the scanning mirror 310, only P-polarized light passes through the P-polarizing filter 51, enters the scattering plate 150, and is scattered. Then, the camera 140 detects the light scattered by the scattering plate 150. Further, the light scattered by the object, which is the light other than the light reflected by the object, is also incident on the scattering plate 150. The light emitted through the scattering plate 150 has a bright spot having a high intensity due to the reflected light and a bright spot having a low intensity due to the light scattered by the object. The control unit 7 may store only the information of the bright spot having high intensity among the information obtained from the camera 140.

Also in this detection device 300, the same operation as the flowchart shown in FIG. 2 is performed.

[Action effect]
Next, the operation and effect of the detection device 300 in the present embodiment will be described.

As described above, the detection device 300 according to the present embodiment further causes the object to scan the scanning mirror 310 that reflects the light from the light source 3 toward the object and the light reflected by the scanning mirror 310. Also includes a scanning mirror 310 and a swinging portion 311 that swings at least one of the light sources 3.

According to this configuration, the state of the object can be detected in a wider range as compared with the configuration in which at least one of the scanning mirror 310 and the light source 3 is not swung.

Further, the detection device 300 according to the present embodiment further includes a scattering plate 150 that scatters light between the object and the light receiving unit 4. Then, the light receiving unit 4 receives the light that has passed through the scattering plate 150.

According to this configuration, the control unit 7 recognizes a bright spot having a high intensity due to the reflected light, a bright spot having a low intensity due to the light scattered by the object, and the like. Therefore, the control unit 7 can detect the distribution of the amount of water in the object.

In particular, in the detection device 300 according to the present embodiment, the light receiving unit 4 is a camera 140. Then, the camera 140 receives the light passing through the scattering plate 150.

According to this configuration, bright spots having high intensity due to reflected light, bright spots having low intensity due to light scattered by an object, and the like are recognized as image information. Therefore, the control unit 7 can detect from the image information indicating the amount of water in the object, which represents the bright spots having high intensity and the bright spots having low intensity.

Further, the detection device 300 according to the present embodiment may include an ND filter between the scattering plate 150 and the light receiving unit 4. Then, the camera 140 may receive the light that has passed through the scattering plate 150 and the ND filter.

According to this configuration, the ND filter allows only the light of the high-intensity bright spot to pass from the light in which the high-intensity bright spot and the low-intensity bright spot are separated by the scattering plate 150. Therefore, it can be reliably detected from the image information indicating the amount of water in the object.

In particular, the light intensity of the entire surface of the scattering plate 150 may be detected by using the light receiving unit 4 having a single pixel instead of the camera 140. In this case, only high-intensity light can be passed from the light of the scattering plate 150 simply by providing the ND filter. Therefore, the water content of the object can be reliably detected with a simple configuration.

The other effects of the present embodiment also have the same effects as those of the first embodiment.

(Embodiment 4)
Hereinafter, the detection device 400 according to the present embodiment will be described.

[Constitution]
The configuration of the detection device 400 according to the present embodiment will be described with reference to FIG.

FIG. 9 is a schematic view showing the detection device 400 according to the fourth embodiment.

The present embodiment is different from the second embodiment in that the reflection mirror 410 is provided and the light reflected or the like is received through the reflection mirror 410 and the object.

The other configurations in the present embodiment are the same as those in the first embodiment, and the same configurations are designated by the same reference numerals and detailed description of the configurations will be omitted.

As shown in FIG. 9, in the second embodiment, the first light source 31, the second light source 32, the control unit 7, the storage unit 11, the power supply unit 9, the polarization separation unit 5, the first light receiving unit 41 and the second light receiving unit 41. In addition to 42, in the present embodiment, the detection device 400 further includes a housing 420 and a reflection mirror 410.

The housing 420 accommodates the first light source 31, the second light source 32, the control unit 7, the storage unit 11, the power supply unit 9, the polarization separation unit 5, the first light receiving unit 41, the second light receiving unit 42, the reflection mirror 410, and the like. It is a box-shaped member.

The first light source 31 and the second light source 32 are provided on the housing 420 so that the light is emitted toward the object.

The reflection mirror 410 is provided so as to face the object. Specifically, the reflection mirror 410 is provided so that the light from the first light source 31 and the second light source 32 is reflected once or more between the object and the reflection mirror 410, respectively. The optical axes of the first light source 31 and the second light source 32 may be directed to the reflection mirror 410. That is, it is sufficient that one or more reflections are performed between the reflection mirror 410 and the object. In the object, the light receiving unit 4 may receive the diffused light.

In such a detection device 400, the light emitted from the first light source 31 and the second light source 32 is reflected between the translucent plate 430 and the object one or more times, and is reflected by the first light receiving unit 41 and the first light receiving unit 41. 2 Proceeds to the light receiving unit 42 side. The first light receiving unit 41 and the second light receiving unit 42 receive the light after reflection or the like between the reflection mirror 410 and the object via the polarization separating unit 5.

Also in this detection device 400, the same operation as the flowchart shown in FIG. 2 is performed.

[Action effect]
Next, the operation and effect of the detection device 400 in the present embodiment will be described.

As described above, the detection device 400 according to the present embodiment further includes a reflection mirror 410 that reflects light, a reflection mirror 410, a light source 3, a light receiving unit 4, a polarization separation unit 5, and a determination unit 71. It is equipped with 420. Then, the reflection mirror 410 is provided on the housing 420 so that one or more reflections occur between the reflection mirror 410 and the object while facing the object.

According to this configuration, since light is repeatedly incident on the object, the state of the object can be detected more accurately, and the reliability and sensitivity of the detection performance can be improved. In particular, it is suitable for detecting a trace amount of water in an object.

The other effects of the present embodiment also have the same effects as those of the first embodiment.

(Modified Example of Embodiment 4)
Hereinafter, the detection device 400 according to the present modification of the fourth embodiment will be described with reference to FIG.

FIG. 10 is a schematic view showing a detection device 400 according to a modified example of the fourth embodiment.

This modification of the fourth embodiment is different from the fourth embodiment in that a light transmitting plate 430 is provided between the reflection mirror 410 and the object.

Other configurations in the present modification of the fourth embodiment are the same as those in the first embodiment, and the same configurations are designated by the same reference numerals and detailed description of the configurations will be omitted.

As shown in FIG. 10, in the present modification of the fourth embodiment, the detection device 400 is provided, for example, on a radiator grill or the like in a vehicle. In addition to the first light source 31, the second light source 32, the control unit 7, the storage unit 11, the power supply unit 9, the polarization separation unit 5, the first light receiving unit 41, and the second light receiving unit 42, the detection device 400 further includes light. It has a transparent light-transmitting plate 430 that allows light to pass through.

The light transmitting plate 430 is provided on the housing 420 in a state of being exposed from the outer peripheral surface of the housing 420. The translucent plate 430 has a boundary surface 431 that is a surface exposed from the housing 420. Snow, rain, etc. adhere to the boundary surface 431. The object in the present modification of the fourth embodiment is rain, snow, or the like attached to the translucent plate 430. As the light transmitting plate 430, any light transmitting plate 430 may be used as long as the absorption rates for the wavelength λ1 and the wavelength λ2 are substantially the same, even if the absorption rate of the incident light is not 0.

The first light source 31 and the second light source 32 are provided so as to enter from the reflection mirror 410 side of the light transmitting plate 430 and reflect at the boundary surface 431.

In such a detection device 400, the light emitted from the first light source 31 and the second light source 32 is reflected between the light transmitting plate 430 and the reflection mirror 410 on the side of the first light receiving unit 41 and the second light receiving unit 42. Proceed towards. Specifically, the light incident on the translucent plate 430 is incident from the reflection mirror 410 side of the translucent plate 430, transmitted through the inside of the transmissive plate 430, and is reflected and reflected by the boundary surface 431 of the transmissive plate 430. Head to Mirror 410. Then, the same reflection is repeated toward the first light receiving unit 41 and the second light receiving unit 42 side. The surface of the translucent plate 430 on the reflection mirror 410 side is coated with a non-reflective coating so that the light reflected by the boundary surface 431 is not reflected on the surface of the translucent plate 430 on the reflection mirror 410 side. It is preferable to keep it. In this case, reflection is suitably repeated between the boundary surface 431 of the light transmitting plate 430 and the reflection mirror 410.

For example, when snow, rain, or the like adheres to the boundary surface 431 of the translucent plate 430, some of the light incident on the boundary surface 431 is diffusely reflected by the boundary surface 431, but some other light is diffusely reflected. It is refracted at the boundary surface 431 of the light transmitting plate 430. Further, when snow or rain does not adhere to the boundary surface 431, it is specularly reflected by the boundary surface 431. In this way, the detection device 400 can detect the object attached to the boundary surface 431. In addition, for example, since an ice film may be formed on the boundary surface 431, the surface may be roughened so that diffuse reflection can be performed. Further, for example, in the case of water, since the interface with the outside becomes substantially flat, specular reflection may occur at the interface.

Also in this detection device 400, the same operation as the flowchart shown in FIG. 2 is performed.

[Action effect]
Next, the operation and effect of the detection device 400 in the present modification of the fourth embodiment will be described.

As described above, the detection device 400 according to the present modification of the fourth embodiment further includes a light transmitting plate 430 having a boundary surface 431 to which an object adheres and transmitting light. The light-transmitting plate 430 is provided so that the boundary surface 431 is exposed from the housing 420 so that reflection occurs one or more times between the light-transmitting plate 430 and the reflection mirror 410.

According to this configuration, since light is repeatedly incident on the boundary surface 431 of the translucent plate 430, the boundary surface 431 of the translucent plate 430 can be detected, and the reliability and sensitivity of the detection performance can be improved. ..

In particular, the detection device 400 can be miniaturized by performing multiple reflections on the boundary surface 431 of the light transmitting plate 430 and the reflection mirror 410.

The other effects of the present modification of the fourth embodiment also have the same effects as those of the first embodiment.

(Embodiment 5)
Hereinafter, the detection device 500 according to the present embodiment will be described with reference to FIG.

[Constitution]
The configuration of the detection device 500 according to the present embodiment will be described with reference to FIG.

FIG. 11 is a schematic view showing the detection device 500 according to the fifth embodiment.

The present embodiment differs from the fourth embodiment in that a light guide 530 (an example of a light transmitting portion) is provided instead of the reflecting mirror 410 and the light transmitting plate 430.

The other configurations in the present embodiment are the same as those in the first embodiment, and the same configurations are designated by the same reference numerals and detailed description of the configurations will be omitted.

In addition to the first light source 31, the second light source 32, the control unit 7, the storage unit 11, the power supply unit 9, the polarization separating unit 5, the first light receiving unit 41, and the second light receiving unit 42, the detection device 500 further includes a light. A guide 530 is provided.

The light guide 530 has an incident surface 531, an exit surface 532, and a boundary surface 533, and is a long translucent member. A first light source 31 and a second light source 32 are provided on one end side of the light guide 530 so that light is incident from the incident surface 531. On the other end side of the light guide 530, a polarization separating unit 5, a first light receiving unit 41, and a second light receiving unit 42 are provided to receive light emitted from the emitting surface 532. The light guide 530 is provided so that the boundary surface 533 is exposed from the outer peripheral surface of the housing 420. The light guide 530 may be made of, for example, a resin such as multi-component glass, quartz, or plastic, or may be a liquid light guide. The boundary surface 533 may also be configured so that the surface can be roughened to allow diffuse reflection.

For example, when the detection device 500 is used in a vehicle, snow, rain, etc. adhere to the boundary surface 533, and when the detection device 500 is used to detect the water content of the skin in the human body, the skin is attached to the boundary surface 533. Contact.

In such a detection device 500, the light emitted from the first light source 31 and the second light source 32 is incident on the incident surface 531 of the light guide 530, is reflected in the light guide 530, and is transmitted through the first light guide 530. It proceeds toward the light receiving unit 41 and the second light receiving unit 42 side.

Also in this detection device 500, the same operation as the flowchart shown in FIG. 2 is performed.

[Action effect]
Next, the operation and effect of the detection device 500 in the present embodiment will be described.

As described above, the detection device 500 according to the present embodiment further includes a boundary surface 533 to which an object adheres, and a light guide 530 that transmits light. The light guide 530 guides the light incident from the light source 3 to the light receiving unit 4 via the polarization separating unit 5.

According to this configuration, since light is repeatedly incident on the boundary surface 533 of the light guide 530, the boundary surface 533 of the light guide 530 can be used as a detection surface, and the reliability and sensitivity of the detection performance can be improved.

In particular, the detection device 500 can be miniaturized by performing multiple reflections in the light guide 530.

The other effects of the present embodiment also have the same effects as those of the first embodiment.

(Embodiment 6)
Hereinafter, the detection device 600 according to the present embodiment will be described.

[Constitution]
The configuration of the detection device 600 according to the present embodiment will be described with reference to FIG.

FIG. 12 is a schematic view showing a vehicle 610 provided with the detection device 600 according to the sixth embodiment.

In the modified example of the first embodiment, the state of the object is detected by irradiating the light of the light source 3 toward the traveling direction of the vehicle 110, but in the present embodiment, the lower side (object side) of the vehicle 610 is detected. ) And its surroundings by irradiating the light of the light source 3 to detect the state of the object.

Other configurations in the present embodiment are the same as those in the modified example of the first embodiment, and the same configurations are designated by the same reference numerals and detailed description of the configurations will be omitted.

As shown in FIG. 12, the vehicle 610 has a detection device 600 and a cylinder 630, and for example, the detection device 600 and the cylinder 630 are housed in the engine room. In the present embodiment, the detection device 600 and the tubular body 630 are provided in the engine room of the vehicle 610, but the present invention is not limited to this, as long as the object under the vehicle 610 is detected. It may be provided in.

The detection device 600 is arranged on one end side of the tubular body 630. That is, the detection device 600 is provided on the side of the cylinder 630 opposite to the object. The detection device 600 detects an object on the lower side of the vehicle 610 via the tubular body 630. In the present embodiment, the object is, for example, the road surface of a road.

The detection device 600 detects the state of the object within the detection range. This detection range is a range in which the state of the object can be detected, and is mainly a range in which the object is irradiated with light. The detection range is an object located below the vehicle 610 and around the lower part of the vehicle 610. Specifically, the detection range is an object directly under the vehicle 610 and around the vehicle 610. In the present embodiment, as an example of the detection range, the range of light emitted from the other end side of the tubular body 630 and radiated to the object.

The tubular body 630 has a tubular shape that guides the light emitted by the light source 3 of the detection device 600 and the light reflected or scattered by the object. In the present embodiment, the tubular body 630 is provided on the vehicle body in a state of being inclined with respect to the vertical direction, but it may be provided substantially parallel to the vertical direction.

The tubular body 630 is a long cylinder, and has a guide hole 631, an opening 631a on one end side, and an opening 631b on the other end side. The guide hole 631 is formed so as to extend in the longitudinal direction. The guide hole 631 penetrates from one end side to the other end side. One end side of the guide hole 631 is the one end side opening 631a, and the other end side of the guide hole 631 is the other end side opening 631b. In the present embodiment, one end side is the upper side and the other end side is the lower side. A detection device 600 is provided in the vicinity of the one-end side opening 631a so that light can be emitted and received (the state of the object is detected via the tubular body 630). The other end side opening 631b faces the object side and is continuous with the outside of the vehicle 610.

The surface forming the guide hole 631 is a light reflecting surface that reflects light, for example, a surface that reflects specularly.

In the present embodiment, the tubular body 630 has a cylindrical shape with a circular cross section, but it may have a tubular shape and may have a polygonal shape or the like. Further, although the diameter of the tubular body 630 is substantially constant, the diameter may gradually increase as the distance from the detection device 600 increases. That is, the object side of the cylinder 630 may have a large diameter, and the detection device 600 side of the cylinder 630 may have a small diameter.

When the state of the object is detected by using such a detection device 600, the light source 3 of the detection device 600 irradiates the object with light through (via) the guide hole 631 of the tubular body 630. Then, the light receiving unit 4 of the detection device 600 receives (via) the light reflected or scattered by the object through the guide hole 631 of the tubular body 630. In this way, the state of the object is detected. The operation of the detection device 600 is the same as that of the first embodiment, and the description thereof will be omitted.

FIG. 13 is a block diagram showing a vehicle 610 of the vehicle support system according to the sixth embodiment. FIG. 14 is a schematic view showing the vehicle support system according to the sixth embodiment.

As shown in FIG. 14, the detection device 600 may constitute a vehicle support system mounted on the vehicle 610. In the vehicle support system, three vehicles 610 are shown as an example, but the number of vehicles is not particularly limited.

As shown in FIG. 13, the detection device 600 includes a communication unit 640 in addition to the light source 3, the control unit 7, the storage unit 11, and the power supply unit 9. The communication unit 640 is a device having an antenna or the like capable of communicating with another vehicle 610.

As shown in FIGS. 13 and 14, the control unit 7 may sequentially share position information from other vehicles 610 traveling on the same road via the communication unit 640. For example, the control unit 7 transmits information on the state of the object in the vicinity of the lower part of the vehicle 610 and the lower part of the vehicle 610 to the following vehicle 610 traveling on the same road via the communication unit 640. May be good. In the present embodiment, for example, information regarding the state of the object detected by the detection device 600 of the leading vehicle 610 may be transmitted to the following two vehicles 610. Then, the following two vehicles 610 may receive the information via the communication unit 640 and output this information to the output unit 8. Further, the two following vehicles 610 may transmit information regarding the state of the object to the following vehicle 610 via the communication unit 640. In this case, since the following vehicle 610 can obtain information on the state of the object from the leading vehicle 610, it becomes easier to avoid danger in the vehicle 610. In addition, each of the following vehicles 610 also detects the state of the object.

Further, the detection device 600 may communicate with the following vehicle 610 using an in-vehicle antenna provided in a car navigation system or the like. Therefore, the communication unit 640 is not an indispensable constituent requirement of the detection device 600.

[Action effect]
Next, the operation and effect of the detection device 600 in the present embodiment will be described.

As described above, in the detection device 600 according to the present embodiment, the detection range in which the detection device 600 detects the state of the object is an object located below the vehicle 610 and around the lower part of the vehicle 610. ..

According to this configuration, in order to detect the state of the object under the vehicle 610, the distance between the detection range and the detection device 600 can be shortened as compared with the case of irradiating light in the traveling direction of the vehicle 610. it can. Therefore, the positional deviation of the detection range due to pitching of the vehicle 610 can be reduced.

Further, in the detection device 600 according to the present embodiment, the vehicle 610 is provided with a tubular body 630 extending in the direction of irradiating the light of the light source 3. Then, the detection device 600 detects the state of the object via the tubular body 630.

According to this configuration, since the detection device 600 detects the state of the object via the tubular body 630, the detection device 600 is farther from the object than when the detection device 600 is directly attached to the lower surface of the vehicle 610. Therefore, it is possible to suppress problems such as light irradiation and light reception not being possible due to mud splashing and the like, and the detection device 600 breaking down due to stone splashing and the like, which occur while the vehicle 610 is traveling.

Further, in this detection device 600, since the cylinder 630 faces the object located below the vehicle 610 and the other end side opening 631b, the guidance of the cylinder 630 is guided even in a rainy or snowy environment. The hole 631 is less likely to be clogged with water or snow. Therefore, false detection of the detection device 600 can be suppressed.

Further, in the detection device 600 according to the present embodiment, the inner surface of the tubular body 630 has a light reflecting surface that reflects light.

According to this configuration, since the light reflecting surface of the tubular body 630 reflects light, it is difficult to reduce the efficiency of light utilization when passing through the tubular body 630.

The other effects of the present embodiment also have the same effects as those of the first embodiment.

(Modified Example of Embodiment 6)
Hereinafter, the detection device 601 according to the present embodiment will be described with reference to FIG.

FIG. 15 is a schematic view showing a vehicle 610 provided with a detection device 601 according to a modification of the sixth embodiment.

In the modified example of the first embodiment, the state of the object is detected by irradiating the light of the light source 3 in the traveling direction of the vehicle 110, but in the modified example of the sixth embodiment, the lower part of the vehicle 610 and the vehicle It differs in that the state of the object is detected by irradiating the light of the light source 3 toward the periphery below the 610.

Other configurations in the present embodiment are the same as those in the modified example of the first embodiment, and the same configurations are designated by the same reference numerals and detailed description of the configurations will be omitted.

The alternate long and short dash line in FIG. 15 is a line that separates the front side (the traveling direction side of the vehicle 610) and the rear side (the side opposite to the traveling direction of the vehicle 610) of the vehicle 610, and passes substantially the center in the length direction of the vehicle 610. It is a line to do.

As shown in FIG. 15, in the objects located below the vehicle 610 and around the lower part of the vehicle 610, the traveling direction side of the vehicle 610 is the first region E1, and the side opposite to the traveling direction of the vehicle 610 is the second region E2. Is. The first region E1 and the second region E2 are different ranges from each other. In the present modification of the sixth embodiment, the detection range in which the detection device 601 detects the state of the object is the second region E2. In FIG. 15, the detection range of the detection device 601 is shown by a broken line, and this detection range includes a part of the second region E2.

The detection device 601 is provided on the rear side of the vehicle 610 (the side opposite to the traveling direction of the vehicle 610). Specifically, the detection device 601 is provided so as to detect the state of the object on the rear side of the vehicle 610 in the objects located below the vehicle 610 and around the lower part of the vehicle 610. That is, the detection device 601 is provided in the vehicle 610 so as to detect the second region E2, which is an object located below the vehicle 610 and around the lower part of the vehicle 610. The detection device 601 may detect the entire area below the vehicle 610.

The detection device 601 detects the state of the object in the second region E2, but may further detect the state of the object in the first region E1.

In the detection device 601 according to the present modification of the sixth embodiment, the objects located below the vehicle 610 and around the lower part of the vehicle 610 are the first region E1 on the traveling direction side of the vehicle 610 and the first region E1. Unlike the one region E1, it has a second region E2 on the side opposite to the traveling direction of the vehicle 610. The detection range of the detection device 601 is the second region E2.

In this way, if the detection device 601 is arranged on the rear side of the vehicle 610 in order to detect the second region E2, irradiation or light reception cannot be performed due to mud splashing or the like, which occurs while the vehicle 610 is running, or stone splashing or the like. As a result, problems such as the detection device 601 failing can be further suppressed.

Further, when the vehicle 610 is equipped with a rear view camera, when the vehicle 610 moves backward (backward), it is possible to detect the state of an object in the range in which the rear wheels travel.

In particular, the detection device 601 is preferably provided at a position away from the wheels 112.

The other effects of the present modification of the sixth embodiment also have the same effects as those of the first embodiment.

(Embodiment 7)
Hereinafter, the detection device 700 according to the present embodiment will be described.

[Constitution]
The configuration of the detection device 700 according to the present embodiment will be described with reference to FIGS. 16 and 17 (a).

FIG. 16 is a schematic view showing a vehicle 710 including the detection device 700 according to the seventh embodiment. FIG. 17A is a schematic view showing the detection device 700 and the wheel 112 according to the seventh embodiment. The straight arrow shown in FIG. 17A indicates the tangential direction along the rotation direction of the wheel 112.

In the modified example of the first embodiment, the state of the object is detected by irradiating the light of the light source 3 toward the traveling direction of the vehicle 110, but in the present embodiment, the light source is directed toward the wheels 112 of the vehicle 710. It differs in that the state of the wheel 112 is detected by irradiating the light of 3.

Other configurations in the present embodiment are the same as those in the modified example of the first embodiment, and the same configurations are designated by the same reference numerals and detailed description of the configurations will be omitted.

As shown in FIGS. 16 and 17 (a), the detection device 700 detects a state on the outer peripheral end surface of the wheel 112 of the vehicle 710 (a surface that comes into contact with an object during traveling (an example of a surface)). It is provided in a tire house that houses the wheels 112. The detection device 700 is provided, for example, in a fender liner forming a tire house. The wheel 112 has a wheel connected to an axle that rotates around an axis O, and a tire provided on the outer circumference of the wheel. The arrangement position of the detection device 700 is not limited to the arrangement of the present embodiment because it is sufficient to detect the state on the outer peripheral end surface of the wheel 112.

The detection device 700 is provided on the vehicle 710 so as to detect the state of the surface of the wheel 112. As shown in FIG. 17A, the direction of irradiating the light of the light source 3 in the detection device 700 is substantially the traveling direction of the vehicle 710. Specifically, the light source 3 of the detection device 700 irradiates light along the tangential direction along the rotation direction of the wheel 112.

[Comparison example]
FIG. 17B is a schematic view showing the detection device 700'and the wheel 112' according to the comparative example. The straight arrow shown in FIG. 17B indicates the tangential direction along the rotation direction of the wheel 112.

As shown in FIG. 17B, the detection device 700'is provided so that the direction of irradiating the light of the light source 3 is opposite to the tangential direction along the rotation direction of the wheel 112'. In this case, when the wheel 112'is rotated, mud, stones, etc. adhering to the wheel 112' are directed toward the tangential direction along the rotation direction of the wheel 112'. For this reason, there are problems such as the inability to irradiate or receive light due to mud splashing or the like, or the detection device 700'breaking down due to stone splashing or the like.

[Action effect]
Next, the operation and effect of the detection device 700 in the present embodiment will be described.

As described above, in the detection device 700 according to the present embodiment, the object is the wheel 112. Then, the detection device 700 is provided on the vehicle 710 so as to detect the state of the surface of the wheel 112.

According to this configuration, since the detection device 700 can be arranged at a position close to the wheels 112, when the light of the light source 3 is irradiated toward the traveling direction of the vehicle 110 as in the modified example of the first embodiment. In comparison, the light emission output of the light source 3 can be reduced. Therefore, energy saving of the detection device 700 can be realized.

Further, since the detection device 700 only needs to identify the tire on the wheel 112 and the water content adhering to the tire, it is compared with the discrimination between the asphalt made of a complicated material and the water content adhering to the asphalt. Therefore, high-precision identification accuracy is not required. Therefore, it is possible to suppress an increase in the manufacturing cost of the detection device 700.

In particular, if this detection device 700 is used in the vehicle 710, it is possible to detect the presence or absence of moisture or the like between the road surface and the tire, so that the grip force of the tire can be grasped more accurately. For example, even when the road surface is changed from a frozen road surface, a snow-covered road surface, or the like while the vehicle is running 710 to a dry road surface, it is possible to grasp the case where the tires are wet due to the influence of the road surface.

Further, in the detection device 700 according to the present embodiment, the light source 3 irradiates light along the tangential direction along the rotation direction of the wheel 112.

According to this configuration, as shown in FIG. 17B, when the wheel 112 is rotated, mud, stones, etc. adhering to the wheel 112 hit the detection device 700 in the tangential direction along the rotation direction of the wheel 112. hard. For this reason, it is unlikely that problems such as the inability to irradiate or receive light due to mud splashing or the failure of the detection device 700 due to stone splashing or the like occur.

The other effects of the present embodiment also have the same effects as those of the first embodiment.

(Other modifications, etc.)
Although the detection device, the detection method, and the detection program according to the present invention have been described above based on each embodiment, the present invention is not limited to the above-described embodiment.

For example, in the above embodiment, in the configuration in which the light receiving unit is arranged on the light source side as shown in FIG. 1 so that the light receiving unit can receive the light scattered by the object, the light receiving unit is specularly reflected by the object. Compared with the case of receiving light, it is possible to suppress the increase in size of the detection device.

Further, in the water of the above embodiment, the reflectance of P-polarized light on the water surface becomes 0 when the incident angle is 53.1 °, so that the incident angle of the emitted light to the object is around 53.1 °. When set to, the ratio of the intensity of P-polarized light of the scattered light to the intensity of S-polarized light can be increased. In this case, the detection accuracy of the detection device can be improved.

Further, in the above embodiment, the output unit may be a display unit that not only displays a frozen state, a flooded state, a snow-covered state, and a dry state, but also outputs characters, images, and the like. Further, the output unit may output audio via a speaker or the like. In this case, when the detection device is applied to the vehicle, the control unit notifies the passenger of the surrounding conditions via the output unit in order to detect the state of the surrounding objects in the vehicle, thereby providing safe driving support. Can be done.

Further, in the above embodiment, when the detection device is applied to the vehicle, the output unit may notify the situation of the surrounding objects in the vehicle when the vehicle stops and the passenger gets off. In this case, it is possible to prevent the passenger from tipping over when getting off due to freezing or the like.

Further, in the above embodiment, when the detection device is applied to the vehicle, the control unit may acquire information such as the driving status of the vehicle and the seatbelt wearing status of the passenger. Then, the output unit may notify the fact when the seat belt is not fastened.

Further, in the above embodiment, when detecting the water content of the skin of the human body, the control unit may store the detected water content of the skin in the storage unit. Then, the control unit may compare the data based on the data detected in the past and output the result.

Further, in the above embodiment, the detection device may be used to detect the water content of the skin in the human body. That is, it can be used in a detection device other than the modification of the second embodiment.

Although one or more aspects of the present invention have been described above based on each embodiment, the present invention is not limited to this embodiment. As long as it does not deviate from the gist of the present invention, one or more of the present embodiments may be modified by those skilled in the art, or may be constructed by combining components in different embodiments. It may be included within the scope of the embodiment.

For example, in each of the above embodiments, each component may be configured by dedicated hardware or may be realized by executing a software program suitable for each component. Each component may be realized by a program execution unit such as a CPU or a processor reading and executing a software program recorded on a recording medium such as a hard disk or a semiconductor memory.

The present invention can be used as a device for detecting a state such as a water content in an object such as a road surface or human skin. When mounted on a vehicle, it can be used in detection devices, detection methods and detection programs used to detect frozen conditions, flooded conditions, snow conditions, and dry conditions on the road surface. Further, in the case of detecting the water content of the skin in the human body, it can also be used as a detection device, a detection method and a detection program used for detecting a dry state and a moisturizing state in the skin.

1,200,300,400,500,600,601,700 Detection device 3 Light source (31 first light source, 32 second light source)
4 Light receiving part (41 first light receiving part, 42 second light receiving part)
5 Polarization separation unit 6 Wavelength separation unit 7 Control unit 8 Output unit 71 Judgment unit 72 Power supply control unit 110, 610, 710 Vehicle 112 Wheels 113 Handle 114 Steering angle detection unit 115 Speed detection unit 140 Camera (light receiving unit)
150 Scattering plate 310 Scanning mirror (reflector)
311 Swing part 420 Housing 430 Translucent plate 431, 533 Boundary surface 530 Light guide (translucent part)
630 cylinder

Claims (24)

A light source that emits light in the first wavelength band and light in the second wavelength band that is less easily absorbed by water than the first wavelength band toward an object.
A polarization separator that separates at least P-polarized light from light containing S-polarized light and P-polarized light reflected or scattered by the object.
A light receiving unit that receives light reflected or scattered by the object via the polarization separating unit, and a light receiving unit.
A control unit that determines the state of the object from information based on the light received by the light receiving unit is provided.
Light emitted from the light source, Ri substantially uniform randomly polarized der proportion of the S-polarized light and the P polarized light,
The control unit
The S1 polarization intensity in the S polarization in the first wavelength band, the P1 polarization intensity in the P polarization in the first wavelength band, and the S2 polarization intensity in the S polarization in the second wavelength band or the second wavelength band. Information based on the P2 polarization intensity in the P polarization is acquired from the light receiving unit.
When the S2 polarization intensity or the P2 polarization intensity is larger than a predetermined threshold value, it is determined that the object is in a snow-covered state.
When the S1 polarization intensity and the S2 polarization intensity are substantially equal, or when the P1 polarization intensity and the P2 polarization intensity are substantially equal, it is determined that the object is in a dry state.
When the P2 polarization intensity is larger than the S2 polarization intensity and the value obtained by dividing the P2 polarization intensity by the S2 polarization intensity is equal to or less than a predetermined value, it is determined that the object is in a flooded state. And
The object is in a frozen state when the P2 polarization intensity is larger than the S2 polarization intensity and when the value obtained by dividing the P2 polarization intensity by the intensity at the S2 polarization intensity is larger than a predetermined value. A detection device that determines that . Further, between the object and the light receiving unit, a wavelength separation unit that separates the light in the first wavelength band and the light in the second wavelength band from the light reflected or scattered by the object is provided. claims 1 Symbol placement of the sensing device. Further, a reflector that reflects light from the light source toward the object,
The detection device according to claim 1 or 2 , further comprising a swinging portion that swings at least one of the reflector and the light source so that the object scans the light reflected by the reflector. Further, a scattering plate for scattering light is provided between the object and the light receiving portion.
The detection device according to any one of claims 1 to 3 , wherein the light receiving unit receives light through the scattering plate. Further, an ND filter is provided between the scattering plate and the light receiving portion.
The detection device according to claim 4 , wherein the light receiving unit receives light that has passed through the scattering plate and the ND filter. Further, a reflection mirror that reflects light and a housing that houses the reflection mirror, the light source, the light receiving unit, the polarization separating unit, and the control unit are provided.
One of claims 1 to 5 , wherein the reflection mirror is provided on the housing so that one or more reflections occur between the reflection mirror and the object while facing the object. The detection device described in. Further, a translucent plate having a boundary surface to which the object is attached and transmitting light is provided.
The detection device according to claim 6 , wherein the light-transmitting plate is provided so that the boundary surface is exposed from the housing so that one or more reflections occur between the light-transmitting plate and the reflection mirror. .. Further, it has a boundary surface to which the object is attached, and is provided with a translucent portion that allows light to pass through.
The detection device according to any one of claims 1 to 7 , wherein the light transmitting unit guides light incident from the light source to the light receiving unit via the polarization separating unit. The light source includes a first light source that emits light in the first wavelength band and a second light source that emits light in the second wavelength band.
The detection device according to any one of claims 1 to 8 , wherein the control unit controls the first light source and the second light source to be alternately turned on and off. The light emitted by the light source is infrared light.
The infrared light in the first wavelength band is light having an absorption peak having an absorption wavelength at any of 740 nm, 980 nm, 1450 nm, and 1940 nm in water.
The detection device according to any one of claims 1 to 9 , wherein the infrared light in the second wavelength band is light having a shorter wavelength than the infrared light in the first wavelength band. The detection device according to any one of claims 1 to 10 , wherein the light receiving unit is a camera. Further, it is provided with an output unit that outputs the state of the object.
The light source emits infrared light and visible light.
The camera
A first image of the object when the light source emits infrared light, and
When the light source emits visible light, a second image of the object is generated and transmitted to the control unit.
Wherein the control unit generates a third image overlaid the first image on the second image received from the camera, sensing apparatus of claim 1 1, wherein for outputting the third image to the output unit. The camera generates a fourth image showing the distance between the object and the camera in the second image and transmits the fourth image to the control unit.
Wherein the control unit, the fourth image received from the camera superimposed with the third image to generate a fifth image, sensing apparatus of claim 1 wherein outputting the fifth image to the output unit. A sensing device according to any one of claims 1 to 1 3 mounted on the vehicle,
The vehicle has wheels steered by a steering wheel, a steering angle detection unit that detects the steering angle of the wheels, and a speed detection unit that detects the traveling speed of the vehicle.
The steering angle detection unit transmits the first information regarding the steering angle of the wheel to the control unit.
The speed detection unit transmits second information regarding the traveling speed of the vehicle to the control unit.
The control unit is a detection device that controls so as to change the direction of irradiation by the light source and the position at which the object is imaged according to the first information and the second information. The detection range of detection apparatus for detecting a state of said object, said as an object located around the lower part of the lower and the vehicle of the vehicle according to claim 1 4, wherein the sensing device. The object located below the vehicle and around the lower part of the vehicle has a first region on the traveling direction side of the vehicle and a second region on the opposite side of the traveling direction of the vehicle, unlike the first region. Has an area and
The detection range, the a second region claim 1 5, wherein the detection device of the detection device. The vehicle is provided with a cylinder extending in the direction of irradiating the light of the light source.
The detection device according to claim 15 or 16 , wherein the detection device detects the state of the object via the cylinder. The detection device according to claim 17 , wherein the inner surface of the cylinder has a light reflecting surface that reflects light. The object is the wheel,
The detection device according to any one of claims 14 to 18 , which is provided on the vehicle so as to detect the state of the wheel surface. The detection device according to claim 19 , wherein the light source irradiates light along a tangential direction along the rotation direction of the wheel. The control unit
Sensing apparatus according to claim 1 4, wherein the farther the object from the detection device is imaged on the light receiving unit in accordance with a steering angle of the wheel increases. The control unit
The claim that as the traveling speed of the vehicle increases, the light receiving unit images the object that is the traveling direction of the vehicle detected by the steering angle detection unit from the steering angle of the wheel and is far from the detection device. 21. The detection device according to 1 . A detection method for detecting a state of an object by using a detection device according to any one of claims 1-2 2,
The control unit
The S1 polarization intensity in the S polarization in the first wavelength band, the P1 polarization intensity in the P polarization in the first wavelength band, and the S2 polarization intensity in the S polarization in the second wavelength band or the second wavelength band. The acquisition step of acquiring information based on the P2 polarization intensity in the P polarization from the light receiving unit, and
A snow cover determination step for determining that the object is in a snow cover state when the S2 polarization intensity or the P2 polarization intensity is larger than a predetermined threshold value.
A drying determination step for determining that the object is in a dry state when the S1 polarization intensity and the S2 polarization intensity are substantially equal to each other, or when the P1 polarization intensity and the P2 polarization intensity are substantially equal to each other.
If the P2 polarization intensity is greater than the step S2 polarization intensity, and, in step S2 polarization intensity, when the value obtained by dividing the P2 polarization intensity is below a predetermined value, when the object is in a state of flooding Submersion judgment step to judge and
The object is in a frozen state when the P2 polarization intensity is larger than the S2 polarization intensity and when the value obtained by dividing the P2 polarization intensity by the intensity at the S2 polarization intensity is larger than a predetermined value. A detection method that includes a freeze determination step to determine that. Detection program for executing the detecting method according to claim 2 3 wherein the computer.

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