JP6584370B2 - Optical radar device for vehicles - Google Patents

Description

  The present invention relates to an optical radar device that detects an object based on reflected light of light projected forward of a vehicle.

  There is known a radar device for a vehicle that detects an object such as a preceding vehicle, a pedestrian, and an obstacle existing in front of the vehicle and measures a distance to the object to prevent a collision in advance. Yes. Such radar devices include a radio wave type and an optical type. Patent Document 1 discloses a radio wave type radar device for a vehicle, and Patent Documents 2 and 3 disclose an optical vehicle radar device.

  The radio wave radar device of Patent Document 1 includes a radar antenna having a narrow beam width and an antenna having a wide beam width. Only with an antenna with a narrow beam width, the detection range in the short distance region becomes narrow, and there is a risk of losing sight of the preceding vehicle due to curves etc., but by installing an antenna with a wide beam width, the detection range in the short distance region widens, It becomes easier to detect the preceding vehicle.

  The optical radar device of Patent Document 2 includes a light emitting device attached above a bumper of a vehicle. The light emitting device is composed of a scanning laser, and projects fan-shaped light beams having a predetermined width in the vehicle width direction and a predetermined spread angle in the vertical direction to the front of the vehicle. This light beam is projected in two stages to form a short distance detection area and a long distance detection area. In the short distance detection region, the light projection distance is short and the light beam spread angle is large. On the other hand, in the long distance detection region, the projection distance of the beam light is long and the spread angle of the beam light is small. Thereby, the object in both the near field and the far field can be detected by one light source.

  The optical radar apparatus of Patent Document 3 includes an optical system that converts laser light emitted from a laser diode into parallel light, and a lens array that diffuses the parallel light horizontally in a plurality of directions. The lens array is composed of a plurality of cylindrical lenses arranged in the horizontal direction. Near the center of the lens array, since the curvature of the lens is small, the spread angle of the laser light is small and the light projection distance is long. On the other hand, near the end of the lens array, the curvature of the lens is large, so the spread angle of the laser beam is large and the light projection distance is short. Therefore, the long distance detection area and the short distance detection area can be optically formed by the lens array.

Japanese Patent Publication No. 3-15713 Japanese Patent No. 3330624 JP 2014-209078 A

  A radar device for preventing collision of vehicles requires a long detection distance in the traveling direction when traveling at high speed on a highway or the like, while traveling at low speed on a meandering road or curve. Although the detection distance may be short, a wide detection region in the vehicle width direction is required. Patent Documents 1 to 3 described above form a short-range detection region and a long-range detection region in consideration of such circumstances, but in Patent Document 1, two projection sources (antennas) are required. Therefore, the configuration becomes complicated. In Patent Document 2, only one projection source (laser) is required, but each detection region is formed by scanning a beam, so that a control circuit for that purpose is required, and the configuration is also complicated.

  On the other hand, according to Patent Document 3, since the long-distance detection area and the short-distance detection area are optically formed by lenses having different curvatures, problems such as Patent Documents 1 and 2 are eliminated. However, in Patent Document 3, the light intensity distribution in the vertical direction of the laser light in the long distance detection region is the same in the upper part and the lower part of the laser light. In the long-distance detection area, the upper part of the laser light is projected far and contributes to detecting a distant object, but the lower part of the laser light is directed to the ground and is not projected far. Does not contribute to detecting distant objects. Therefore, in the laser diode, electric energy corresponding to the light intensity of the lower part of the laser beam in the long-distance detection region is wasted.

  The subject of this invention is providing the optical radar apparatus for vehicles which can form a long distance detection area and a short distance detection area, suppressing the power consumption of a light emitting element.

  An optical radar device for a vehicle according to the present invention includes a light projecting unit that projects light toward the front of the vehicle, and a light receiving unit that receives the light reflected by an object located in front of the vehicle. The light projecting unit includes a light emitting element that emits light, and a light projecting lens that diffuses light emitted from the light emitting element in the vehicle width direction and the vertical direction of the vehicle and projects the light forward. The light projecting lens diffuses the light so that the spread angle in the vehicle width direction in the lower region of the light to be projected is larger than the spread angle in the vehicle width direction in the upper region.

  According to such a configuration, the upper detection area having a small divergence angle and high light intensity and the lower detection area having a large divergence angle and low light intensity are formed by the light projected from the light projecting lens. For this reason, it is possible to detect a distant object by the upper detection region, and it is possible to detect a nearby object by the lower detection region. Further, by concentrating the light on the upper detection region necessary for detecting a distant object, the energy of the entire light can be reduced and the power consumption of the light emitting element can be reduced.

  In the present invention, the light projecting lens may include a plurality of cylindrical lenses arranged in the vehicle width direction. In this case, each of the cylindrical lenses is formed so that the lower curvature is larger than the upper curvature.

  In the present invention, each of the cylindrical lenses may include an upper cylindrical lens having a first curvature and a lower cylindrical lens having a second curvature larger than the first curvature.

  In the present invention, each of the cylindrical lenses may be formed in a shape in which the curvature gradually increases from the upper side to the lower side.

  In the present invention, the light projecting lens may include a single cylindrical lens. In this case, the cylindrical lens is formed such that the lower curvature is larger than the upper curvature.

  In the present invention, the single cylindrical lens may be composed of an upper cylindrical lens having a first curvature and a lower cylindrical lens having a second curvature larger than the first curvature.

  In the present invention, the single cylindrical lens may be formed in a shape in which the curvature gradually increases from the upper side to the lower side.

  In the present invention, a collimating lens that converts light emitted from the light emitting element into parallel light may be formed integrally with the light projecting lens.

  ADVANTAGE OF THE INVENTION According to this invention, the optical radar apparatus for vehicles which can form a long distance detection area and a short distance detection area, suppressing the power consumption of a light emitting element can be provided.

1 is a block diagram of an optical radar device according to the present invention. It is a front view of the vehicle carrying an optical radar apparatus. It is a perspective view which shows the external appearance of an optical radar apparatus. It is a perspective view which shows the external appearance of the light projection lens of 1st Embodiment. It is the top view, front view, bottom view, and left side view of the projection lens. It is a figure which shows the detection area which the lens single-piece | unit of the light projection lens forms. It is a figure which shows the detection area | region which the lens array of the light projection lens forms. It is a figure which shows the optical system of a light projection part. It is a figure which shows the detection area | region formed ahead of a vehicle. It is a figure which shows the intensity distribution of the light in each detection area. It is a figure explaining a long distance detection area and a short distance detection area. It is a perspective view which shows the external appearance of the light projection lens of 2nd Embodiment. It is the top view, front view, bottom view, and left side view of the projection lens. It is a figure which shows the detection area which the lens single-piece | unit of the light projection lens forms. It is a figure which shows the detection area | region which the lens array of the light projection lens forms. It is a perspective view which shows the external appearance of the light projection lens of 3rd Embodiment. It is a perspective view which shows the external appearance of the light projection lens of 4th Embodiment. It is a perspective view which shows the external appearance of the light projection lens of 5th Embodiment. It is a perspective view which shows the external appearance of the light projection lens of 6th Embodiment. It is a perspective view which shows the external appearance of the light projection lens of 7th Embodiment. It is a perspective view which shows the external appearance of the light projection lens of 8th Embodiment.

  Hereinafter, embodiments of an optical radar device for a vehicle according to the present invention (hereinafter simply referred to as “optical radar device”) will be described with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals.

  First, the overall configuration of the optical radar apparatus will be described with reference to FIG. 1 to 3 are common to the embodiments described later.

  An optical radar device 100 shown in FIG. 1 is a device mounted on a vehicle, and is provided on an inner upper portion of a windshield 201 of a vehicle 200, for example, as shown in FIG. In FIG. 2, X represents the vehicle width direction, and Y represents the vertical direction (the same applies to FIG. 3 and subsequent figures). The optical radar apparatus 100 detects an object such as a preceding vehicle, a pedestrian, or an obstacle existing in front of the vehicle 200 and measures a distance from the vehicle 200 to the object. The optical radar apparatus 100 includes a light projecting unit 1, a light receiving unit 2, a signal processing unit 3, an object detection unit 4, a control unit 5, and an output unit 6.

  The light projecting unit 1 includes a light projecting lens 12, a light emitting element 13, and a drive circuit 14. The light projecting lens 12 projects the light emitted from the light emitting element 13 to the front of the vehicle 200. In the present embodiment, the light emitting element 13 is composed of a laser diode. The drive circuit 14 supplies a drive current to the light emitting element 13 to cause the element to emit light. Although not shown in FIG. 1, a collimator lens 11 is disposed between the light projecting lens 12 and the light emitting element 13 as shown in FIG.

  The light receiving unit 2 includes a light receiving lens 21 and a light receiving element 22. The light receiving lens 21 condenses the reflected light that is reflected from the object by the laser light projected from the light projecting lens 12. In the present embodiment, the light receiving element 22 is constituted by a photodiode, and receives light collected by the light receiving lens 21 and converts it into an electrical signal.

  The signal processing unit 3 includes an amplifier circuit that amplifies the electric signal output from the light receiving element 22, an A / D converter circuit that samples the output signal of the amplifier circuit, and converts the signal into a digital signal. The output of the signal processing unit 3 is given to the object detection unit 4.

  Based on the output signal of the signal processing unit 3, the object detection unit 4 detects an object such as a preceding vehicle, a pedestrian, or an obstacle existing in front of the vehicle 200, and calculates a distance from the vehicle 200 to the object. To do. Since these specific methods are well known and are not the features of the present invention, detailed description thereof will be omitted. The output of the object detection unit 4 is given to the control unit 5.

  The control unit 5 includes a microcomputer and performs predetermined control on the light projecting unit 1, the light receiving unit 2, and the signal processing unit 3. Further, the control unit 5 determines whether or not there is an abnormal approach with a preceding vehicle, a pedestrian, or an obstacle based on the output signal of the object detection unit 4, and sends the determination result to the output unit 6.

  The output unit 6 outputs the determination result received from the control unit 5 to an electronic control device (not shown) mounted on the vehicle. When it is necessary to notify the driver of the abnormality based on the determination result, the electronic control device displays an alarm on the display in the vehicle or outputs an audio alarm from the speaker. The electronic control unit also performs control such as automatically operating a brake in order to prevent a collision.

  FIG. 3 shows an example of the appearance of the optical radar apparatus 100. The optical radar apparatus 100 includes a housing 40 made of synthetic resin, and the light projecting lens 12, the light receiving lens 21, and the raindrop sensor 15 are accommodated in the housing 40. The housing 40 includes a cover 40a and a case 40b to which the cover 40a is fitted. Three openings 41 to 43 are formed in the cover 40a. The light projecting lens 12 faces the opening 41, the light receiving lens 21 faces the opening 42, and the raindrop sensor 15 faces the opening 43. For example, the raindrop sensor 15 projects infrared light and detects the amount of raindrops based on the amount of infrared light reflected by the windshield. In the present invention, since the raindrop sensor 15 is not essential, the illustration is omitted in FIG. Each block of the signal processing unit 3, the object detection unit 4, the control unit 5, and the output unit 6 in FIG. 1 is provided on a circuit board (not shown) disposed inside the case 40b.

  Next, the projector lens 12 that is a feature of the present invention will be described in detail. First, the structure of the light projecting lens 12 according to the first embodiment will be described with reference to FIGS. FIG. 4 shows the appearance of the light projecting lens 12 of the first embodiment. 5A is a plan view of the light projecting lens 12, FIG. 5B is a front view thereof, FIG. 5C is a bottom view thereof, and FIG. 5D is a left side view thereof.

  As shown in FIG. 4, the light projecting lens 12 includes a base portion 120 and a lens portion 123. The base 120 is formed in a rectangular parallelepiped shape that does not cause light refraction. The lens unit 123 includes an upper lens unit 121 and a lower lens unit 122. The upper lens portion 121 is formed integrally with the base portion 120 on the upper side of the base portion 120, and includes a lens array in which a plurality of upper cylindrical lenses 12a are arranged in the vehicle width direction X. Each of the upper cylindrical lenses 12a is a convex lens. The lower lens portion 122 is formed integrally with the base portion 120 below the base portion 120, and includes a lens array in which a plurality of lower cylindrical lenses 12b are arranged in the vehicle width direction X. Each of the upper cylindrical lens 12a and each of the lower cylindrical lens 12b is paired and is continuous in the vertical direction Y (see FIGS. 5B and 5D). Further, the curvature (second curvature) of the lower cylindrical lens 12b is larger than the curvature (first curvature) of the upper cylindrical lens 12a (see FIGS. 4 and 5C).

  FIG. 6 is a diagram schematically showing a single lens 12P obtained by cutting out one cylindrical lens 12a, 12b from the light projecting lens 12 of FIG. 4, and a diffusion state of laser light by the single lens 12P. Since the curvature of the upper cylindrical lens 12a of the single lens 12P is small, the extent of the laser light projected from the lens is small. On the other hand, since the curvature of the lower cylindrical lens 12b of the single lens 12P is large, the extent of the laser light projected from the lens is large. As a result, as shown in FIG. 6A, the upper light projection area Ra having a narrow width in the vehicle width direction X is formed by the laser light projected from the upper half of the single lens 12P, and the bottom of the single lens 12P. The lower light projection region Rb having a wide width in the vehicle width direction X is formed by the laser light projected from the half. The laser light projected from the single lens 12P is diffused in the vertical direction Y as shown in FIG.

  FIG. 7 is a diagram schematically showing a diffusion state of the laser light projected from the entire lens array of the light projecting lens 12. As described above, the single lens 12P in FIG. 6 forms the narrow upper projection region Ra and the wide lower projection region Rb. As a result, as shown in FIG. By the emitted laser light, an upper light emitting region R1 having a narrow width in the vehicle width direction X and a lower light projecting region R2 having a wide width in the vehicle width direction X are formed.

  In FIG. 7, a collimating lens 11 is disposed behind the light projecting lens 12. As shown in FIG. 8, the collimating lens 11 is interposed between the light emitting element 13 (laser diode) and the light projecting lens 12, and converts the laser light emitted from the light emitting element 13 into parallel light. The light enters the light projection lens 12. The parallel light incident on the light projecting lens 12 is diffused in the vehicle width direction X and the vertical direction Y in the upper cylindrical lens 12a and the lower cylindrical lens 12b, and the upper light projecting region R1 and the lower side as shown in FIG. A light projection region R2 is formed.

  FIG. 9 is a schematic diagram showing a detection area formed in front of the vehicle by the laser light projected from the optical radar device 100 mounted on the vehicle 200. α represents the spread angle in the vehicle width direction X in the upper region of the projected laser beam, and β represents the spread angle in the vehicle width direction X in the lower region of the projected laser beam. . As can be seen from FIG. 9, the spread angle β of the lower region is larger than the spread angle α of the upper region (β> α). The upper projection area R1 with the spread angle α is a detection area formed between the position a and the b position in the vertical direction Y, and the lower projection area R2 with the spread angle β is the position b in the vertical direction Y. And a detection region formed between the c positions. Hereinafter, R1 is referred to as an upper detection region, and R2 is referred to as a lower detection region. Note that the hatched portions in FIG. 9 represent the cross sections of the detection regions R1 and R2 at the position of the broken line W in FIG.

  The laser light emitted from the light emitting element 13 has a uniform light intensity on the upper side and the lower side, but the laser light that has passed through the light projecting lens 10 does not have a uniform light intensity on the upper side and the lower side. FIG. 10 shows the normalized intensity distribution of the laser beam in the hatched portion of FIG. The horizontal axis represents the positions a, b, and c in the vertical direction Y in FIG. 9, and the vertical axis represents the light intensity of the laser light. In the upper detection region R1, since the spread angle α is small and the diffusion of the laser light is small, the light energy per unit area increases and the light intensity increases. On the other hand, in the lower detection region R2, since the spread angle β is large and the diffusion of the laser light is large, the light energy per unit area is reduced and the light intensity is reduced.

  As described above, in this embodiment, the light intensity distribution in the vertical direction Y of the laser light is different between the upper detection region R1 and the lower detection region R2. The laser beam reaches farther as the light intensity increases. Therefore, as shown in FIG. 11, the upper detection region R1 is a long-distance detection region where laser light having a small divergence angle α and high light intensity reaches far, and the lower detection region R2 is a light having a large divergence angle β. A laser beam with low intensity becomes a short-range detection region that does not reach far.

  In FIG. 11, when the preceding vehicle 300 is traveling in front of the vehicle 200, the optical radar device 100 mounted on the vehicle 200 detects the preceding vehicle 300 in the upper detection region R1 (far distance detection region). be able to. On the other hand, an object M (pedestrian or obstacle) located obliquely forward near the vehicle 200 cannot be detected in the upper detection region R1 having a small spread angle α. However, the object M can be detected in the lower detection region R2 (short-range detection region) having a large spread angle β.

  As described above, according to the present embodiment, the projection lens 12 in which a plurality of cylindrical lenses 12a and 12b are arranged in the vehicle width direction X is used, and the curvature of the lower cylindrical lens 12b is set to the curvature of the upper cylindrical lens 12a. Is bigger than. For this reason, the upper detection region R1 (far-distance detection region) having a small divergence angle α and the lower detection region R2 (short-distance detection region) having a large divergence angle β by the laser light projected from the projection lens 12. Therefore, it is possible to detect both an object in the distance and an object in the vicinity. In addition, since these detection regions R1 and R2 are optically formed by the light projection lens 12, it is not necessary to scan the laser beam as in Patent Document 2.

  Moreover, according to the present embodiment, as described above, the light intensity distribution in the vertical direction Y of the laser light is different between the upper detection region R1 and the lower detection region R2, and the light intensity of the lower detection region R2 is different. However, it is smaller than the light intensity of the upper detection region R1. In Patent Document 2 and Patent Document 3, laser light having a uniform light intensity distribution in the vertical direction is projected to form a long-distance detection region, and therefore, a lower region that does not contribute to detection of a distant object. Light energy is wasted. However, in the present embodiment, since the intensity of the laser light is increased only in the upper detection region R1, the waste of light energy in the lower detection region R2 can be eliminated. That is, by concentrating light on the upper detection region R1 necessary for detecting a distant object, the light energy of the entire laser light can be reduced, and the power consumption of the laser diode (light emitting element 13) can be reduced.

  Next, a second embodiment of the light projecting lens 12 will be described with reference to FIGS. First, the structure of the light projecting lens 12 according to the present embodiment will be described with reference to FIGS. FIG. 12 shows the appearance of the light projecting lens 12 of the second embodiment. 13A is a plan view of the light projecting lens 12, FIG. 13B is a front view thereof, FIG. 13C is a bottom view thereof, and FIG. 13D is a left side view thereof.

  As shown in FIG. 12, the light projecting lens 12 includes a base portion 120 and a lens portion 123. The base 120 is formed in a rectangular parallelepiped shape that does not cause light refraction. The lens portion 123 is formed integrally with the base portion 120, and includes a lens array in which a plurality of cylindrical lenses 12c are arranged in the vehicle width direction X. Each cylindrical lens 12c is composed of a convex lens. Each cylindrical lens 12c is formed in a shape in which the curvature gradually increases from the upper side to the lower side, and has the smallest curvature at the upper end of the lens and the largest curvature at the lower end of the lens (see FIGS. 12 and 13 (a)). ) (C)).

  FIG. 14 is a diagram schematically showing a single lens 12Q obtained by cutting out one cylindrical lens 12c from the light projecting lens 12 of FIG. 12, and a diffusion state of laser light by the single lens 12Q. Since the curvature at the upper end of the cylindrical lens 12c is small, the extent of the laser light projected from the lens is small. On the other hand, since the curvature at the lower end of the cylindrical lens 12c is large, the extent of the spread of the laser light projected from the lens is large. Since the curvature gradually increases from the upper end to the lower end of the cylindrical lens 12c, the extent of the spread of the laser light also gradually increases. As a result, as shown in FIG. 14A, the upper light projection region Rc having a narrow width in the vehicle width direction X is formed by the laser light projected from the upper half of the single lens 12Q, and the bottom of the single lens 12Q. The lower light projection region Rd having a wide width in the vehicle width direction X is formed by the laser light projected from the half. The laser light projected from the single lens 12Q is diffused in the vertical direction Y as shown in FIG.

  FIG. 15 is a diagram schematically showing the diffusion state of the laser light projected from the entire lens array of the light projecting lens 12. As described above, as a result of forming the narrow upper light projecting region Rc and the wide lower light projecting region Rd by the single lens 12Q of FIG. 14, the light projecting from the light projecting lens 12 as shown in FIG. The upper detection region R3 having a narrow width in the vehicle width direction X and the lower detection region R4 having a wide width in the vehicle width direction X are formed by the laser light. The collimating lens 11 shown in FIG. 15 is the same as the collimating lens 11 shown in FIG. 7 and is interposed between the light emitting element 13 (laser diode) and the light projecting lens 12.

  Even when the projection lens 12 of the second embodiment as described above is used, an upper detection region R3 (a long-distance detection region) having a small divergence angle and a large light intensity and a light intensity having a large divergence angle in front of the vehicle. A lower detection region R4 (short-range detection region) having a small height can be formed. For this reason, as in the first embodiment, it is possible to detect both an object at a long distance and an object at a short distance.

  Also in the second embodiment, the light intensity distribution in the vertical direction Y of the laser light is different between the upper detection region R3 and the lower detection region R4, and the light intensity of the lower detection region R4 is the same as that of the upper detection region R3. It becomes smaller than the light intensity. For this reason, as in the first embodiment, the waste of light energy in the lower detection region R4 that does not contribute to the detection of a distant object is eliminated, the light energy of the entire laser light is reduced, and the power consumption of the light emitting element 13 is reduced. Can be reduced.

  Next, still another embodiment of the light projecting lens will be described with reference to FIGS.

  FIG. 16 is an external view of the light projecting lens 12 according to the third embodiment. The light projecting lens 12 is a modification of the light projecting lens 12 shown in FIG. 4, and is formed by integrally forming a collimating lens 12f. The collimating lens 12f is formed integrally with the base 120 on the side opposite to the lens portion 123, and makes the laser light enter the lens portion 123 as parallel light. The other parts are the same as those of the light projecting lens 12 in FIG. According to the present embodiment, as compared with the case where the collimating lens 11 is provided separately from the light projecting lens 12 as shown in FIG. 7, the positional accuracy of the collimating lens 12f with respect to the lens portion 123 is improved, and the number of parts is reduced and the number of assembly steps is reduced. Can be reduced.

  FIG. 17 is an external view of the light projecting lens 12 according to the fourth embodiment. This light projecting lens 12 is a modification of the light projecting lens 12 shown in FIG. 12, and is formed by integrally forming a collimating lens 12f similar to FIG. Other parts are the same as those of the projection lens 12 of FIG. Also in this embodiment, as compared with the case where the collimating lens 11 is provided separately from the light projecting lens 12 as shown in FIG. 15, the positional accuracy of the collimating lens 12f with respect to the lens portion 123 is improved, and the number of parts is reduced and the number of assembly steps is reduced. Can be reduced.

  FIG. 18 is an external view of the light projecting lens 12 according to the fifth embodiment. The light projecting lens 12 is a modification of the light projecting lens 12 shown in FIG. 4, and the lens portion 123 is composed of two single cylindrical lenses 12A and 12B. 12A is an upper cylindrical lens that constitutes the upper lens part, and 12B is a lower cylindrical lens that constitutes the lower lens part. The curvature (second curvature) of the lower cylindrical lens 12B is larger than the curvature (first curvature) of the upper cylindrical lens 12A. According to the present embodiment, the lens can be easily processed as compared with the projection lens 12 having the lens array as shown in FIG.

  FIG. 19 is an external view of the light projecting lens 12 according to the sixth embodiment. The light projecting lens 12 is a modification of the light projecting lens 12 shown in FIG. 12, and the lens portion 123 is configured by one single cylindrical lens 12C. The cylindrical lens 12C is formed in a shape in which the curvature gradually increases from the upper side to the lower side. In the case of this embodiment, the lens can be easily processed as compared with the projection lens 12 having the lens array as shown in FIG.

  FIG. 20 is an external view of the light projection lens 32 according to the seventh embodiment. The projection lens 32 is a concave lens formed from the cylindrical lens of the projection lens 12 shown in FIG. Specifically, the light projecting lens 32 includes a base portion 320 and a lens portion 323. The base 320 is formed in a rectangular parallelepiped shape that does not cause light refraction. The lens unit 323 includes an upper lens unit 321 and a lower lens unit 322. The upper lens portion 321 is integrally formed with the base portion 320 on the upper side of the base portion 320, and includes a lens array in which a plurality of upper cylindrical lenses 32a are arranged in the vehicle width direction X. Each of the upper cylindrical lenses 32a is composed of a concave lens. The lower lens portion 322 is formed integrally with the base portion 320 below the base portion 320, and includes a lens array in which a plurality of lower cylindrical lenses 32b are arranged in the vehicle width direction X. Each of the upper cylindrical lenses 32a and each of the lower cylindrical lenses 32b are paired and are continuous in the vertical direction Y. Further, the curvature (second curvature) of the lower cylindrical lens 32b is larger than the curvature (first curvature) of the upper cylindrical lens 32a.

  As described above, even when the cylindrical lenses 32a and 32b are configured as concave lenses, the laser beam spread angle is small in the upper cylindrical lens 32a having a small curvature, and the laser beam spread angle is increased in the lower cylindrical lens 32b having a large curvature. . Therefore, the light projection lens 32 has the same function as the light projection lens 12 of FIG.

  FIG. 21 is an external view of a light projection lens 32 according to the eighth embodiment. The projection lens 32 is a concave lens formed from the cylindrical lens of the projection lens 12 shown in FIG. Specifically, the light projecting lens 32 includes a base portion 320 and a lens portion 323. The base 320 is formed in a rectangular parallelepiped shape that does not cause light refraction. The lens unit 323 includes a lens array in which a plurality of cylindrical lenses 32c are arranged in the vehicle width direction X. Each of the cylindrical lenses 32c is formed of a concave lens, and is formed in a shape in which the curvature gradually increases from the upper side to the lower side.

  As described above, even when the cylindrical lens 32c is configured as a concave lens, the spread angle of the laser beam is small on the upper side having a small curvature, and the spread angle of the laser beam is increased on the lower side having a large curvature. Therefore, the light projection lens 32 has the same function as the light projection lens 12 of FIG.

  In the present invention, various embodiments can be adopted in addition to the embodiments described above. For example, the collimating lens 12f shown in FIGS. 16 and 17 may be formed integrally with the light projecting lenses 12 and 32 of FIGS. Also, the cylindrical lenses 12A and 12B in FIG. 18 and the cylindrical lens 12C in FIG. 19 may be concave lenses.

  In FIGS. 4 and 16, the upper cylindrical lens 12a and the lower cylindrical lens 12b are both convex lenses. However, the upper cylindrical lens 12a may be a convex lens and the lower cylindrical lens 12b may be a concave lens. Conversely, the upper cylindrical lens 12a may be a concave lens and the lower cylindrical lens 12b may be a convex lens. Similarly, in FIG. 18, the upper cylindrical lens 12A may be a convex lens and the lower cylindrical lens 12B may be a concave lens. Conversely, the upper cylindrical lens 12A may be a concave lens and the lower cylindrical lens 12B may be a convex lens.

  12 and 17, the cylindrical lens 12c may be shaped such that the upper half is a convex lens and the lower half is a concave lens, or the upper half is a concave lens and the lower half is a convex lens. Similarly, in FIG. 19, the cylindrical lens 12C may be shaped such that the upper half is a convex lens and the lower half is a concave lens, or the upper half is a concave lens and the lower half is a convex lens.

DESCRIPTION OF SYMBOLS 1 Light projection part 2 Light reception part 11, 11f Collimating lens 12, 32 Light projection lens 12a, 12A, 32a Upper cylindrical lens 12b, 12B, 32b Lower cylindrical lens 12c, 12C, 32c Cylindrical lens 13 Light emitting element 21 Light reception lens 22 Light reception Element 120, 320 Base 121, 321 Upper lens part 122, 322 Lower lens part 123, 323 Lens part 100 Optical radar device for vehicle 200 Vehicle R1, R3 Upper detection area (far distance detection area)
R2, R4 Lower detection area (short distance detection area)
X Vehicle width direction Y Vertical direction α Light spread angle in the vehicle width direction (upper region)
β Light spread angle in the vehicle width direction (lower area)

Claims (8)

A light projecting unit that projects light in front of the vehicle;
A light receiving unit that receives the light reflected by an object in front of the vehicle,
The light projecting unit is
A light emitting element for emitting the light;
In a vehicular optical radar apparatus comprising: a light projecting lens that diffuses light emitted from the light emitting element in a vehicle width direction and a vertical direction of the vehicle and projects the light forward.
The light projecting lens diffuses the light so that the spread angle in the vehicle width direction in the lower region of the light to be projected is larger than the spread angle in the vehicle width direction in the upper region. An optical radar device for vehicles. The optical radar device for a vehicle according to claim 1,
The projection lens is
It has a plurality of cylindrical lenses arranged in the vehicle width direction,
Each of the cylindrical lenses is formed so that a lower curvature is larger than an upper curvature. In the optical radar device for vehicles according to claim 2,
Each of the cylindrical lenses is
An upper cylindrical lens having a first curvature;
An optical radar device for a vehicle, comprising: a lower cylindrical lens having a second curvature larger than the first curvature. In the optical radar device for vehicles according to claim 2,
Each of the cylindrical lenses is formed in a shape in which the curvature gradually increases from the upper side to the lower side, and is an optical radar device for vehicles. The optical radar device for a vehicle according to claim 1,
The projection lens is
With a single cylindrical lens,
The vehicular optical radar device, wherein the cylindrical lens is formed such that a lower curvature is larger than an upper curvature. The optical radar device for a vehicle according to claim 5,
The single cylindrical lens is
An upper cylindrical lens having a first curvature;
An optical radar device for a vehicle, comprising: a lower cylindrical lens having a second curvature larger than the first curvature. The optical radar device for a vehicle according to claim 5,
The vehicular optical radar device, wherein the single cylindrical lens is formed in a shape in which the curvature gradually increases from the upper side to the lower side. The optical radar device for a vehicle according to any one of claims 1 to 7,
A collimating lens that converts light emitted from the light emitting element into parallel light;
The vehicular optical radar apparatus, wherein the collimating lens is formed integrally with the light projecting lens.

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