Patent Publication Number: US-2019169909-A1

Title: Window glass raising and lowering device for vehicle, vehicle door, and vehicle

Description:
FIELD OF INVENTION 
     The invention relates to a vehicle window glass raising/lowering device, a vehicle door, and a vehicle. 
     BACKGROUND ART 
     A vehicle window glass raising/lowering device which raises and lowers a vehicle window glass of a door automatically is known. 
     The vehicle window glass raising/lowering device includes a driving unit for generating a driving force for raising and lowering the window glass and a control unit for controlling the driving unit. Since the window glasses are electrically raised or lowered, the vehicle window glass raising/lowering devices are generally provided with a mechanism to prevent pinching by window glass. 
     As a vehicle window glass raising/lowering device, the present applicant has proposed a vehicle window glass raising/lowering device that includes a camera for imaging the detection line provided along the window frame and that causes a driving mechanism to perform a pinch preventing operation for preventing pinching in a window glass, when at least a part of the detection line imaged by the camera is shielded by a foreign object (see PTL 1). 
     PTL 1 discloses a vehicle window glass raising/lowering device including a light source section having a plural light emitting elements for emitting infrared light toward a detection line. In this vehicle window glass raising/lowering device, by imaging infrared light radiated from the plural light emitting elements and reflected by the detection line with a camera arranged in the vicinity of the light source section, it is possible to detect a foreign object which may be pinched even at night, etc. 
     CITATION LIST 
     Patent Literature 
     
         
         PTL 1: JP 5768202 B 
       
    
     SUMMARY OF INVENTION 
     Technical Problem 
     By the way, in the vehicle window glass raising/lowering device including a pinch prevention mechanism as disclosed in PTL 1, in order to reliably detect a foreign object that may be caught, it is desirable to configure the detection line so that a light from the light source is reflected in a specific direction (the direction in which the camera exists) since the light from the light source is reflected by the detection line and captured by the camera. 
     It is an object of the invention to provide a vehicle window glass raising/lowering device that can reliably detect a foreign object that may be caught, as well as a vehicle door and a vehicle using the vehicle window glass raising/lowering device. 
     Solution to Problem 
     According to an embodiment of the invention, a vehicle window glass raising/lowering device comprises: 
     a drive unit arranged on a vehicle door to move a window glass in a vertical direction; 
     a control unit for controlling the drive unit; 
     a detection line arranged on a vehicle interior side of the window glass and along at least a portion of an outer edge of the window glass in a state where the door and the window glass are closed; 
     a light source comprising a light emitting element to emit an invisible light to the detection line; and 
     a camera comprising a lens on which the invisible light emitted from the light source and reflected by the detection line is incident, 
     wherein the control unit comprises a pinching prevention means that causes the drive unit to perform a pinch prevention operation for preventing pinching by the window glass based on an image taken by the camera, and 
     wherein the detection line comprises a reflection layer to reflect an incident light toward the light source. 
     According to another embodiment of the invention, a vehicle door comprises the vehicle window glass raising/lowering device described above. 
     According to another embodiment of the invention, a vehicle comprises the vehicle door described above. 
     Effects of Invention 
     According to an embodiment of the invention, it is possible to provide a vehicle window glass raising/lowering device that can reliably detect a foreign object that may be caught, as well as a vehicle door and a vehicle using the vehicle window glass raising/lowering device. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is an explanatory diagram illustrating a vehicle window glass raising/lowering device in an embodiment of the present invention. 
         FIG. 2  is an explanatory diagram illustrating a door when viewed from the upper side inside a vehicle. 
         FIG. 3  is an explanatory diagram illustrating the door when viewed from the lower-front side of the vehicle. 
         FIG. 4A  is cross-sectional view in which the door is cut in the vertical direction at the position including the camera. 
         FIG. 4B  is a view for explaining the installation position of the camera unit shown in  FIG. 4A . 
         FIG. 5A  is cross-sectional view showing the configuration of the detection line. 
         FIG. 5B  is an explanatory diagram illustrating a microbead-type retroreflective material. 
         FIG. 6  is a cross-sectional view of a detection line schematically shown for explaining a visible light and an infrared light incident on a detection line. 
         FIG. 7  is a schematic cross-sectional view for explaining a visible light and an infrared light incident on a detection line in a detection line according to a comparative example. 
         FIG. 8A  is an explanatory view showing a state of a vehicle irradiated with a headlight from a position behind the vehicle. 
         FIG. 8B  is a cross-sectional view of a detection line mounted on a vehicle irradiated with the headlight shown in  FIG. 8A , taken along the vehicle longitudinal direction. 
         FIG. 9A  is an explanatory view showing a state of a vehicle irradiated with a headlight from a position on the side of the vehicle. 
         FIG. 9B  is a cross-sectional view of a detection line mounted on a vehicle irradiated with a headlight, taken along the vehicle longitudinal direction. 
         FIG. 10A  is an explanatory view showing a detection line according to the present embodiment. 
         FIG. 10B  is an explanatory view showing a detection line according to a comparative example. 
         FIG. 11  is a flowchart showing a control flow of a vehicle window glass raising/lowering device. 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     Embodiment 
     An embodiment of the invention will be described below in reference to the drawings. 
     FIG. 1  is an explanatory diagram illustrating a vehicle window glass raising/lowering device in the present embodiment. 
     A door  2  of a vehicle(vehicle door) mounting a vehicle window glass raising/lowering device  1  has a storage portion  21  for housing a window glass  3  and a windowpane frame portion  22  provided above the storage portion  21 . A door trim  23  is attached on the vehicle interior side of the storage portion  21  so as to cover the storage portion  21 . 
     The windowpane frame portion  22  is composed of a rear upright portion  22   a  extending upwards from an end of the storage portion  21  on the rear side in the front-back direction of the vehicle, a front upright portion  22   b  extending upwards from the storage portion  21  on the front side with respect to the rear upright portion  22   a , and an upper extended portion  22   c  extending from the top end of the rear upright portion  22   a  to the top end of the front upright portion  22   b . When the window glass  3  is fully closed, the window glass  3  is positioned in a space surrounded by the windowpane frame portion  22  and the upper edge portion of the door trim  23 . That is, the windowpane frame portion  22  and the upper end portion of the door trim  23  constitute the window frame  25 . In the present embodiment, the window frame  25  refers to a portion in contact with an outer edge of the window glass  3  in a state where the door  2  and the window glass  3  are closed in the fully closed state. 
     The vehicle window glass raising/lowering device  1  includes a drive mechanism  4  for moving the window glass  3  between an open position and a closed position with respect to a frame portion (a window frame  25 ) having an opening  25   a  and a control unit  5  for controlling the drive mechanism  4 . 
     The drive mechanism  4  is to move the window glass  3  vertically relative to the windowpane frame portion  22 , and is provided with a motor  41  such as DC motor and a power conversion mechanism  42  for converting a drive force of the motor  41  into power to vertically move the window glass  3 . The power conversion mechanism  42  which can be used here is, e.g., a window regulator which is provided with a carrier plate supporting the window glass  3  and sliding along a guide rail and is configured to slide a wire along the guide rail by a drive force of the motor  41  and thereby to vertically move the carrier plate attached to the wire and the window glass  3  along the guide rail. An X-Arm type or another type of regulator can be also used as the power conversion mechanism  42 . 
     A switch (SW)  24  is provided on the door  2  to open/close the window glass  3 . An output signal line of the switch  24  is connected to the control unit  5 . The switch  24  is constructed from, e.g., a two-stage click-type rocker switch which is configured to output a signal to the control unit  5 , such that a first-level move-down click signal is output when an end on the move-down side is clicked to the first level, a second-level move-down click signal is output when the end on the move-down side is clicked to the second level, a first-level move-up click signal is output when the other end on the move-up side is clicked to the first level, and a second-level move-up click signal is output when the other end on the move-up side is clicked to the second level. 
     The control unit  5  controls the drive unit  4  according to the signal from the switch  24  to vertically move the window glass  3 . The control unit  5 , as a control unit constructed by appropriately combining CPU, memory, interface and software, etc., is mounted on the door  2 . Other than on the door  2 , the control unit  5  may alternatively be mounted as a part of, e.g., an electronic control unit (ECU) which controls mirrors or seats of the vehicle. 
     The control unit  5  is configured to control the drive unit  4  such that when a first-level move-down click signal is input from the switch  24 , the window glass  3  is lowered during when the signal is being input, and when a second-level move-down click signal is input, the window glass  3  continues to move down until the window glass  3  reaches the bottom or the switch  24  is operated again. Also, the control unit  5  controls the drive unit  4  such that when a first-level move-up click signal is input from the switch  24 , the window glass  3  is raised during when the signal is being input, and when a second-level move-up click signal is input, the window glass  3  continues to move up until the window glass  3  reaches the top or the switch  24  is operated again. 
     Next, a configuration to prevent pinching by the window glass  3  will be described. 
     The vehicle window glass raising/lowering device  1  includes a detection line  6  arranged on the vehicle interior side of the window glass  3  along at least a part of an outer edge of the window glass  3  in a state where the door  2  and the window glass  3  are closed. In the present embodiment, the detection line  6  is formed by a retroreflective material along at least a part of the frame portion (the window frame  25 ). 
     The vehicle window glass raising/lowering device  1  includes a light source section  8  that emits an invisible light to the detection line  6  and a camera  7  having an optical system  71  on which the invisible light radiated from the light source section  8  and reflected by the detection line  6  is incident. In the present embodiment, it is determined whether or not there is a foreign object that may be caught by the window glass  3  based on an image captured by the camera  7 . 
     In the present embodiment, as the light source section  8 , one that irradiates near infrared light was used. The camera  7  is composed of an image sensor that images near infrared light irradiated from the light source section  8  and reflected by the detection line  6 . Since the light source section  8  are provided, a foreign object to be possibly pinched can be detected also during the night, or in a dark place even in a daytime where infrared light does not reach, e.g., in an underground parking, etc. 
     The detection line  6  is a reference line for judging the existence of a foreign object to be possibly pinched by the window glass  3 , and is provided on the vehicle interior side with respect to the window glass  3  in a state where the door  2  and the window glass  3  are closed. A specific configuration and setting position of the detection line  6  will be described later. 
     The control unit  5  includes a detection unit  51  that detects a shielding state in which at least a part of the detection line  6  imaged by the camera  7  is shielded by a foreign object and an pinching prevention unit  52  that causes the drive unit  4  to perform an entrapment prevention operation for preventing pinching by the window glass  3  when the shielding state is detected by the detection unit  51  when the window glass  3  is moved by the driving unit  4 . The detection unit  51  is one embodiment of a detection means of the present invention, and the pinching prevention unit  52  is one embodiment of a pinching prevention means. 
     The detection unit  51  is provided with an image processing section  51   a  which processes an image captured by the camera  7  and extracts the detection line  6 , and a blocked state determination section  51   b  which determines, based on the image processed by the image processing section  51   a , whether or not it is the blocked state in which the detection line  6  is at least partially blocked by a foreign object. 
     A specific method of extracting the detection line  6  by the image processing section  51   a  is not specifically limited. For example, when an unnecessary portion is removed by trimming the image captured by the camera  7  and posterization process, binarization process or edge detection process is performed, the detection line  6  with brightness different from surrounding members can be extracted. 
     The blocked state determination section  51   b  is configured that, for example, an image in a non-blocked state (which is an image after being processed by the image processing section  51   a ) is preliminarily stored as an initial state image, and whether or not the detection line  6  is blocked by a foreign object is determined by comparing the initial state image to an image output from the image processing section  51   a.    
     The pinching prevention unit  52  causes the drive unit  4  to perform a pinch prevention operation for preventing pinching by the window glass  3  when the blocked state is detected by the detection unit  51  during when the window glass  3  is moved by the drive unit  4 . The pinch prevention operation includes an operation of stopping movement of the window glass  3 , an operation of lowering the window glass  3  to a safe position, an operation of warning an operator by sound or light from an alarm device installed inside the vehicle, and a combination thereof. 
     The control unit  5  is further provided with a command cancellation unit  53  which cancels a command from the switch  24  when the blocked state is detected by the detection unit  51  after a command to move the window glass  3  is issued from the switch  24  but before the window glass  3  starts to move. Since the command cancellation unit  53  is provided, the window glass  3  does not move during when the blocked state is detected, and safety is thus further improved. 
     Next, specific configurations, etc., of the camera  7  and the light source section  8  will be described. 
       FIG. 2  is an explanatory diagram illustrating a door  2  when viewed from the upper side inside a vehicle.  FIG. 3  is an explanatory diagram illustrating the door  2  when viewed from the lower-front side of the vehicle.  FIG. 4A  is cross-sectional view in which the door is cut in the vertical direction at the position including the camera  7 .  FIG. 4B  is a view for explaining the installation position of the camera unit  110  shown in  FIG. 4A . 
     As shown in  FIGS. 2 to 4B , in the vehicle window glass raising/lowering device  1  of the present embodiment, the camera  7  has an optical system  71  including lenses  71   a  to  71   d  into which the invisible light (near infrared light) radiated from the light source  8  and reflected by the detection line  6  is incident, and an image pickup element  72  on which a subject image is formed by the optical system  71 , and the optical system  71  is arranged at a position corresponding to the opening  23  a formed in an upper surface S of the door trim  23  so that an optical axis C of the optical system  71  passes through the opening  25 . 
     In other words, in the present embodiment, the camera  7  is provided on an upper surface S of the door trim  23 . The upper surface S of the door trim  23  here is an outer surface of the door trim  23  at a top edge portion and is a surface which is visible from above in a vertical direction. The upper surface S of the door trim  23  may be inclined with respect to the vehicle width direction (horizontal direction). The door trim  23  is generally curved such that the upper surface S has the highest portion in the vicinity of the window glass  3 , i.e., in the vicinity of an exit slot  21   a  allowing the window glass  3  to come out from the storage portion  21 , and slopes down as a distance from the window glass  3  increases. Thus, the upper surface S of the door trim  23  is an outer surface of the door trim  23  (the portion corresponding to the inner peripheral surface of the lower side of the window frame  25 ) in the vicinity of the window glass  3  (the exit slot  21   a ). 
     An opening  23   a  is formed closer to the vehicle interior than the exit slot  21   a  and the optical system  71  of the camera  7  is arranged so that the optical axis C is located closer to the vehicle interior side than the exit slot  21   a . Although the camera  7  in this example is arranged so that the optical axis C of the optical system  71  coincides with the vertical direction when viewed in the cross section in FIG. 4 A, the optical axis C of the optical system  71  may be inclined with respect to the vertical direction in the front-back direction of the vehicle or in the vehicle width direction, and can be appropriately adjusted according to the installed position or desired imaging range of the camera  7 . 
     In the present embodiment, the camera  7  is disposed in a hole  23  b provided at a position on the front side of the vehicle on the upper surface S of the door trim  23  (a position on the front side of the upper surface S of the door trim  23  facing the window glass  3 ). Here, as an example, a case where the camera  7  is provided on the upper surface S of the door trim  23  will be described, but the position at which the camera  7  is installed is not limited thereto. 
     The camera  7  has a columnar shape as a whole and has a flange  73  which is formed at a top end so as to protrude radially outward. The camera  7  is inserted into the hole  23   b  from the upper side of the door trim  23  and engages with a groove (not shown) provided in the camera  7  with a locking claw  23   d  provided on the peripheral edge below the hole  23   b . As a result, the camera  7  is fixed to the door trim  23 . Further, the structure for fixing the camera  7  to the door trim  23  and the insertion direction of the camera  7  are not particularly limited, and can be appropriately changed. 
     It is desirable to use a wide-angle lens as the optical system  71  of the camera  7  so that a foreign object can be detected in the range described above. As the optical system  71 , an ultra-wide angle lens with a combination of four lenses  71   a  to  71   d  so as to have a viewing range of not less than 180°, or 190° taking into account the installation precision, in the front-back direction of the vehicle was used. The number of the lenses  71   a  to  71   d  constituting the optical system  71  is not limited to four, and the specific shapes of the respective lenses  71   a  to  71   d  are not limited to those shown in the drawings. 
     Meanwhile, to quickly detect the foreign object, the frame rate of the image pickup element  72  used is desirably as high as possible. In the present embodiment, a CMOS (Complementary MOS) image sensor is used as the image pickup element  72 . The image pickup element  72  is mounted on the circuit board  100 . 
     The light source  8  is configured such that the entire detection line  6  is exposed to radiation. Although two light sources  8  are used in this example to emit the invisible light (near infrared light) onto the entire detection line  6  arranged on an entire inner peripheral surface of the windowpane frame portion  22 , the number of the light sources  8  is not limited thereto. 
     The two light sources  8  are disposed so as to sandwich the camera  7  from the front and back in the front-rear direction of the vehicle. In the present embodiment, the camera unit  110  is formed by integrating the two light sources  8  and the camera  7 . By configuring the camera unit  110 , it is easy to attach the camera  7  and the light source  8 . 
     In the present embodiment, the light source  8  includes a light emitting element  81  mounted on the circuit board  100  and emitting the invisible light (near infrared light), a light guide member  82  for guiding the invisible light (near infrared light) from the light emitting element  81  and a diffusion plate  83  that diffuses and emits the invisible light (near infrared light) guided from the light emitting element  81  via the light guide member  82 . The diffusion plate  83  diffuses and irradiates the invisible light from the light emitting element  81  in a wide range. The diffusion plate  83  is embedded in the through hole  23 e formed in the upper surface S of the door trim  23 . The light guide member  82  guides the invisible light (near infrared light) from the light emitting element  81  mounted on the circuit board  100  to the diffuser plate  83 . The light guide member  82  is composed of, e.g., an optical waveguide and an optical fiber. The light emitting element  81  is composed of, e.g., a light emitting diode. 
     A detection surface  9  described hereinafter is a plane formed by connecting points between the optical system  71  of the camera  7  and the detection line  6  at which the foreign object when located thereon causes the blocked state. The detection surface  9  is substantially the same as a plane connecting the center of the optical system  71  (the center in the vehicle width direction, the height direction and the front-back direction of the vehicle) and the detection line  6 , although depending on the specific configuration of the optical system  71 . It should be noted that the entire detection surface  9  may not be a continuous surface. For example, when the detection line  6  is not continuous, the detection surface  9  is composed of plural surfaces. 
     Next, a specific configuration of the detection line  6  will be described. 
     The detection line  6  is formed along at least a part of an outer edge of the window glass  3  in a state where the door  2  and the window glass  3  are closed and is set on the inner side of the window glass  3  with respect to the window glass  3 . In the present embodiment, the detection line  6  is set so as to be along the entire windowpane frame portion  22  and spaced from the windowpane  3  toward the vehicle interior. 
     The detection line  6  only needs to be set along the window frame  25 , and may be set on the door  2  or on the vehicle body. Further, the detection line  6  may not be continuous, a part of which may be set on the door  2 , and a part thereof may be set on the vehicle body. 
     In the present embodiment, as an example, a case where the detection line  6  is set on the door  2  side will be described. In this case, the detection line  6  is set on an inner peripheral edge surface of the entire windowpane frame portion  22 , that is, an entire inner peripheral edge surface of a rear upright portion  22   a , a front upright portion  22   b , and a upper extended portion  22   c , and is set to be separated from the window glass  3  toward the vehicle interior. The inner peripheral edge surface of the windowpane frame portion  22  is a surface facing the window glass  3  of the windowpane frame portion  22 , and is located on the front side surface of the vehicle in the rear upright portion  22   a , the rear surface of the vehicle in the front upright portion  22   b , the lower surface of the upper extended portion  22   c . That is, the inner peripheral edge surface of the windowpane frame portion  22  is a portion of the outer peripheral surface of the windowpane frame portion  22  in the vicinity of the window glass  3 . 
     As shown in  FIGS. 5A and 5B , in the present embodiment, the detection line  6  includes a reflection layer  61  made of a microbead-type retroreflective material, an absorption layer  62  formed on the incident side of the non-visible light of the reflection layer  61  and absorbing the visible light, a weathering layer  63  formed on a surface of the absorption layer  62  on an incident side of the invisible light, an antireflection layer  64  for preventing a regular reflection of the visible light incident from an outside of the weathering layer  63 , a resin holding layer  65  formed between the reflection layer  61  and the absorption layer  62  and holding plural glass beads  61   b  of the reflection layer  61 , and ,e.g., an adhesive layer  66  formed on the surface opposite to the holding layer  65  of the reflective layer  61 . It should be noted that the absorption layer  62  is included in the “absorbing agent” in the present invention and the antireflection layer  64  is included in the “antireflection agent” in the present invention. 
     The retroreflective member reflects the incident light toward the light source section. A microbead-type retroreflective material using minute glass beads (a microbead) and a prism type retroreflective material using a prism on a small triangular pyramid are known. Among them, since the prism type retroreflective material is expensive, in the present embodiment, a microbead-type retroreflective material is used for the detection line  6 . 
     The reflection layer  61  made of a microbead-type retroreflective material includes a reflective material layer  61   a  and glass beads  61   b  arranged apart from each other. The reflecting material layer  61   a  is formed by applying aluminum vapor deposition to plural glass beads  61   b  embedded in the holding layer  65 , e.g. The adhesive layer  66  is formed on a surface opposite to the glass bead  61   b  of the reflecting material layer  61   a  made of an aluminum vapor-deposited layer. As a result, corrosion of aluminum deposition in the reflecting material layer  61   a  is prevented. 
     As shown in  FIG. 5B , the light incident on the glass bead  61   b  is refracted at the surface of the glass bead  61   b , reflected by the reflecting material layer  61   a , refracted again at the surface of the glass bead  61   b , and then reflected light is emitted in the light incidence direction. 
     The absorption layer  62  is formed at a position sandwiching the holding layer  65  between the absorption layer  62  and the reflection layer  61 . In addition, by cutting the visible light, the absorption layer  62  prevents the driver from feeling dazzling by the visible light being retro-reflected by the reflection layer  61 . The absorption layer  62  can be constituted, e.g., by coating a visible light absorbing dye that absorbs a specific wavelength, or by kneading it in an acrylic resin. 
     The weathering layer  63  is made of, e.g., PET (polyethylene terephthalate) or acrylic resin and is for protecting the absorption layer  62 . 
     The antireflection layer  64  suppresses a regular reflection of the visible light. The antireflection layer  64  is formed by, e.g., coating the surface of the weathering layer  63 . More specifically, the antireflection layer  64  is formed, e.g., by applying silica-doped coding, phase-separating or embossing the coating material. Alternatively, the antireflection layer  64  may be formed by embossing the surface of the weathering layer  63  or by sandblasting. 
       FIG. 6  is a cross-sectional view of a detection line shown for explaining the visible light and infrared light incident on the detection line  6 . In  FIG. 6 , the glass beads  61   b , the holding layer  65  and the adhesive layer  66  shown in  FIG. 5  are not shown for convenience of explanation. 
     As shown in  FIG. 6 , the invisible light (infrared light) incident on the detection line  6  from the light source section  8  (shown in  FIG. 4( b ) ) passes through the antireflection layer  64 , the weathering layer  63 , and the absorption layer  62  and the retro-reflects on the surface of the reflection layer  61 . The visible light coming from the outside (e.g., a headlight of a following vehicle) passes through the antireflection layer  64  and the weathering layer  63  and is absorbed by the absorption layer  62 . In this manner, the detection line  6  is configured so that the visible light is absorbed and a retro-reflection does not occur, and infrared light emitted from the light source  8  causes the retro-reflection. 
     At this time, since the antireflection layer  64  is formed on the surface of the weathering layer  63  as a matting treatment, part of a reflected light that the visible light is reflected by the antireflection layer  64  is configured to diffusely reflect (broken line shown in  FIG. 6 ). Thereby, the regular reflection on the surface of the antireflection layer  64  of visible light is reduced. That is, by increasing the diffuse reflection component of the total reflection amount of visible light on the surface of the antireflection layer  64 , the regular reflection component is reduced. A part of the invisible light (infrared light) incident on the detection line  6  diffuses in the antireflection layer  64 . As this diffusion amount, only a small amount which does not affect the retro-reflection in the reflection layer  61 . 
     Next, the function and effect of the detection line  6  according to the present embodiment will be described with reference to  FIGS. 7 and 10 . Here, for the sake of convenience of explanation, the function effect of the detection line  6  will be described separately for the effect of the absorption layer  62  and the function effect of the antireflection layer  64 . The function and effect of the absorption layer  62  will be described with reference to  FIG. 8 , and the function and effect of the antireflection layer  64  will be described with reference to  FIG. 9 . 
       FIG. 7  is a schematic cross-sectional view of the detection line  6 A according to the comparative example. The detection line  6 A according to the comparative example is configured in the same manner as the detection line  6  according to the present embodiment shown in  FIGS. 5A and 5B , except that it does not include the absorption layer  62  and the antireflection layer  64 . In  FIG. 7 , components having substantially the same functions as those described in this embodiment are denoted by the same reference numerals, and redundant description is omitted. 
     As shown in  FIG. 7 , the invisible light (infrared light) incident on the detection line  6 A from the light source section  8  (shown in  FIG. 4B ) passes through the weathering layer  63  and retro-reflects on the surface of the reflection layer  61 . The visible light that passes through the weathering layer  63  among visible light (e.g., a headlight  900  of a following vehicle to be described later) incident from the outside is retro-reflected on the surface of the reflection layer  61 . On the other hand, most of the visible light incident from the outside is reflected regularly on the surface of the weathering layer  63  (broken line shown in  FIG. 7 ). That is, in the comparative example, as compared with the present embodiment, the regular reflection component of the visible light incident on the detection line  6 A is large and retro-reflects. The invisible light (infrared light) incident on the detection line  6 A according to the comparative example passes through the weathering layer  63  and retro-reflects on the surface of the reflection layer  61 . 
     Next, the function and effect of the absorption layer  62  of the detection line  6  according to the present embodiment will be described with reference to  FIGS. 8A and 8B .  FIG. 8A  shows a state in a case where a vehicle  91  on which the detection line  6  is mounted is irradiated with the headlight  900  (visible light) from the other vehicle  92  positioned behind the vehicle  91  toward the inner surface of the door  2  of the vehicle  91 .  FIG. 8B  is a cross-sectional view when the detection line  6  of the vehicle  91  shown in  FIG. 8A  and the peripheral portion thereof are cut along the vehicle longitudinal direction. 
     As shown in  FIG. 8A , another vehicle  92  may irradiate the headlight  900  (visible light) toward the inner side surface of the door  2  of the vehicle  91  in a situation in which another vehicle  92  is positioned directly behind the vehicle  91  having the detection line  6  according to the present embodiment. Then, as shown in  FIG. 8B , the headlight  900  is incident on the detection line  6  arranged at a position near the front upright portion  22   b  of the windowpane frame portion  22 . 
     In this case, in the case of the present embodiment, the headlight  900  of the other vehicle  92  is not absorbed by the absorption layer  62  and is not retro-reflected by the reflection layer  61 . However, in the case of the detection line  6 A according to the comparative example, since the absorption layer  62  is not provided, the headlight  900  may be retro-reflected and retro-reflected toward the driver  901  (as shown by a two-dot chain line). As described above, since the detection line  6  according to the present embodiment includes the absorption layer  62 , by preventing the retro-reflection of the visible light detection line  6  of the headlight  900 , the influence of the driver on the field of vision is reduced. 
     Next, the function and effect of the antireflection layer  64  of the detection line  6  according to the present embodiment will be described with reference to  FIGS. 9A and 9B .  FIG. 9A  shows a state in a case where the vehicle  91  on which the detection line  6  is mounted is irradiated with the headlight  900  (visible light) from the other vehicle  92  positioned at the rear of the vehicle  91  toward the outer side face of the door  2  of the vehicle  91 .  FIG. 9B  is a sectional view of the detection line  6  of the vehicle  91  shown in  FIG. 9A  and its peripheral portion cut along the vehicle longitudinal direction. 
     As shown in  FIG. 9A , the other vehicle  92  may irradiate the headlight  900  (visible light) toward the outer side face of the door  2  of the vehicle  91  in a situation where another vehicle  92  is positioned behind the vehicle  91  having the detection line  6  according to the present embodiment. Then, as shown in  FIG. 9B , the headlight  900  is incident on the detection line  6  disposed at a position near the front upright portion  22   b  of the windowpane frame portion  22 . 
     In this case, in the case of this embodiment, since the headlight  900  of the other vehicle  92  is diffusely reflected by the surface of the antireflection layer  64 , the regular reflection component is reduced. However, in the case of the detection line  6 A according to the comparative example, since the antireflection layer  64  is not provided, the regular reflection component of the headlight  900  is large (two-dot chain line shown in  FIG. 9B ). As described above, since the detection line  6  according to the present embodiment includes the antireflection layer  64 , by reducing the regular reflection component of the visible light detection line  6  of the headlight  900 , the influence on the driver&#39;s visual field is reduced. 
       FIG. 10A  is an explanatory diagram showing the detection line  6  according to the present embodiment.  FIG. 10B  is an explanatory diagram showing a detection line  6 A according to a comparative example. As shown in  FIG. 10A , the detection line  6  according to the present embodiment shows that the reflected light is reduced more than the detection line  6 A according to the comparative example shown in  FIG. 10B . That is, the retro-reflection and the regular reflection in the detection line  6  are suppressed, and the influence on the driver&#39;s field of vision can be reduced. 
     Next, a control flow of the vehicle window glass raising/lowering device  1  will be described. 
     As shown in FIG. 11 , the vehicle window glass raising/lowering device  1  is configured such that the control unit  5  firstly judges whether or not a signal is input from the switch  24  at Step S 1 . If judged as NO at Step S 1 , the control unit  5  controls the camera  7  and the light source section  8  to be turned off (or kept in the off-state) at Step S 2  and the flow is allowed to return to Step S 1 . 
     If judged as YES at Step S 1 , the control unit  5  controls the camera  7  and the light source section  8  to be turned on (or kept in the on-state) at Step S 3  and the flow is allowed to proceed to Step S 4 . 
     At Step S 4 , the detection unit  51  (i.e., the image processing section  51   a  and the blocked state determination section  51   b ) performs a processing of detecting the blocked state (i.e., a blocked state detection processing) based on the image captured by the camera  7 . After that, at Step S 5 , the command cancellation unit  53  judges whether or not the blocked state is detected by the detection unit  51 . 
     If judged as YES at Step S 5 , the command cancellation unit  53  determines that there is a risk of being pinched by the window glass  3  and the flow is allowed to return to Step S 1  without moving the window glass  3  (i.e., the signal from the switch  24  is cancelled). 
     If judged as NO at Step S 5 , the control unit  5  judges whether or not the signal input from the switch  24  is a first-level click signal (a first-level move-down click signal or a first-level move-up click signal) at Step S 6 . 
     If judged as YES at Step S 6 , the control unit  5  instructs the drive unit  4  to control the movement of the window glass  3  at Step S 7 . 
     After that, at Step S 8 , the detection unit  51  performs a processing of detecting the blocked state (i.e., a blocked state detection processing) based on the image captured by the camera  7 . After that, at Step S 9 , the pinching prevention unit  52  judges whether or not the blocked state is detected by the detection unit  51 . 
     If judged as YES at Step S 9 , there is a risk of being pinched by the window glass  3 . Accordingly, the pinching prevention unit  52  performs a pinch prevention operation such as halting the movement of the window glass  3  or lowering the window glass  3  to the safe position at Step S 10 . After that, the control unit  5  terminates the movement of the window glass  3  at Step S 18  and the flow is allowed to return to Step S 2 . As described above, in the present embodiment, if the blocked state is detected while the first-level click signal is being input from the switch  24 , the movement of the window glass  3  is terminated after performing the pinch prevention operation. 
     If judged as NO at Step S 9 , there is no risk of being pinched by the window glass  3 . Accordingly, the control unit  5  judges whether or not a signal is input from the switch  24  at Step S 11 . If judged as NO at Step S 11 , this means that an operation on the switch  24  is finished. Accordingly, the control unit  5  terminates the movement of the window glass  3  at Step S 18  and the flow is allowed to return to Step S 2 . If judged as YES at Step S 11 , the flow is allowed to return to Step S 6  and the window glass  3  is kept moving. 
     On the other hand, if judged as NO at Step S 6 , i.e., if a second-level click signal (a second-level move-down click signal or a second-level move-up click signal) is input from the switch  24 , the control unit  5  instructs the drive unit  4  to control the movement of the window glass  3  at Step S 12 . 
     After that, at Step S 13 , the detection unit  51  performs a processing of detecting the blocked state (i.e., a blocked state detection processing) based on the image captured by the camera  7 . After that, at Step S 14 , the pinching prevention unit  52  judges whether or not the blocked state is detected by the detection unit  51 . 
     If judged as YES at Step S 14 , there is a risk of being pinched by the window glass  3 . Accordingly, the pinching prevention unit  52  performs a pinch prevention operation at Step S 15 . After that, the movement of the window glass  3  is terminated at Step S 18  and the flow is allowed to return to Step S 2 . In other words, in the present embodiment, if the second-level click signal is input from the switch  24  and the blocked state is detected during when the window glass  3  is moving, the movement of the window glass  3  is terminated after performing the pinch prevention operation. 
     If judged as NO at Step S 14 , there is no risk of being pinched by the window glass  3 . Accordingly, the control unit  5  judges whether or not the window glass  3  is moved to an edge (to the top or bottom end) at Step S 16 . If judge as YES at Step S 16 , the control unit  5  terminates the movement of the window glass  3  at Step S 18  and the flow is allowed to return to Step S 2 . Meanwhile, the positional information of the window glass  3  may be obtained by using a rotational pulse generated by a Hall IC incorporated in the motor  41 , or using current ripple. 
     If judged as at Step S 16 , it is judged whether or not a new signal is input from the switch  24  (i.e., whether or not a new signal is input after the second-level click signal is input) at Step S 17 . If judged as YES at Step S 17 , the flow is allowed to return to Step S 6 . If judged as NO at Step S 17 , the flow is allowed to return to Step S 12  and the window glass  3  is kept moving. That is, if the second-level click signal is input, the window glass  3  is kept moving until the blocked state is detected, the window glass  3  is moved to an edge or a new signal is input from the switch  24 . 
     As described above, according to the detection line  6  having the configuration described in  FIGS. 1 to 11 , it is possible to prevent the retro-reflection and the regular reflection of the visible light while ensuring the retro-reflection of infrared light as detection light for detecting the shielding state of the detection line  6 . 
     (Functions and Effects of the Embodiment) 
     As described above, in the vehicle window glass raising/lowering device  1  according to the present embodiment, the detection line  6  is formed of a retroreflective material. With such a configuration, the camera  7  can efficiently detect the invisible light. As a result, it is possible to realize the vehicle window glass raising/lowering device  1  capable of reliably detecting the foreign object having a possibility of being caught. 
     Further, in the present embodiment, since the detection line  6  is formed of a relatively inexpensive microbead-type retroreflective material, the cost can be suppressed. 
     In the present embodiment, the retroreflective material of the detection line  6  is formed with an antireflection layer  64  that absorbs the visible light incident from the outside. Thus, since the visible light is prevented from the retroreflecting at the reflection layer  61 , it is possible to prevent the visible light from obstructing the visibility of the driver. That is, in the case where the absorption layer  62  is not provided, there is a possibility that the visible light which enters the reflection layer  61  and retro-reflected may hinder the driver&#39;s visibility, but such situation is prevented. That is, the safety can be improved. 
     In the present embodiment, an antireflection layer  64  is formed on the retroreflective material of the detection line  6  to prevent reflection of the incident light incident from the outside. Thereby, the regular reflection component of the visible light on the detection line  6  can be reduced. In other words, it is possible to prevent the visibility of the driver from being obstructed by regular reflection caused by an unintended light source (such as a headlight of the following vehicle), and it is possible to further enhance the safety. 
     Although the embodiment of the present invention has been described above, the embodiment described above does not limit the invention according to the claims. It should also be noted that not all combinations of features described in the embodiments are indispensable for means for solving the problem of the invention. Further, the present invention can be carried out by appropriately deforming and implementing within the scope not deviating from the gist thereof. 
     In the above embodiment, only the case where the weathering layer  63  is formed on the surface of the antireflection layer  64  has been described. However, since the weathering layer  63  is not an essential component in the present invention, e.g., the antireflection layer  64  may be formed directly on the surface of the absorption layer  62 . 
     In the above embodiment, only the case where the reflection layer  61 , the absorption layer  62 , the weathering layer  63 , the antireflection layer  64  and the holding layer  65  are formed as a single independent layer has been described. However, the present invention is not limited thereto, and it may be configured so as to be included in another layer. 
     More specifically, in the above-described embodiment, the absorption layer  62  and the antireflection layer  64  are separated layers, but, for example, it is also possible to form a layer to include the function of the antireflection layer  64  in the absorption layer  62  by embossing the surface of the absorption layer  62  or applying sand blasting. The “antireflection agent” in the present invention also includes those obtained by stamping or sandblasting the surface of the independent absorption layer  62  as described above. 
     Further, the absorption layer  62  may be formed as a holding layer for holding the glass beads  61   b . Thereby, the absorption layer  62  can replace the holding layer  65 . 
     In the above-described embodiment, the case where the glass beads  61   b  are used for the reflection layer  61  has been described. However, the present invention is not limited thereto, and e.g., acryl beads may be used instead of the glass beads  61   b . In this case, by incorporating a visible light absorbing dye into the acrylic beads, it is also possible to include an absorption agent for absorbing visible light incident from the outside into the reflection layer  61 . 
     Also, although not mentioned in the above embodiment, the vehicle window glass raising/lowering device  1  is provided with a safety device for determining various kinds of safety operations such as judging that the foreign object is caught by the window glass  3  and automatically reversing and lowering the moving direction of the window glass  3  when the number of revolutions of the motor  41  is monitored and the load increases during the ascent of the window glass  3  and the revolution number of the motor  41  decreases. 
     REFERENCE SIGNS LIST 
       1  VEHICLE WINDOW GLASS RAISING/LOWERING DEVICE 
       3  WINDOW GLASS 
       4  DRIVE UNIT 
       5  CONTROL UNIT 
       51  DETECTION UNIT (DETECTION MEANS) 
       52  PINCHING PREVENTION UNIT (PINCHING PREVENTION MEANS) 
       6  DETECTION LINE 
       61  REFLECTION LAYER 
       62  ABSORPTION LAYER 
       63  WEATHERING LAYER 
       64  ANTIREFLECTION LAYER 
       7  CAMERA 
       71  OPTICAL SYSTEM 
       8  LIGHT SOURCE SECTION 
       25  WINDOW FRAME (FRAME PORTION)