Vehicular head lamp

Abstract

To provide a vehicular head lamp which can remove fog on an outer lens without a heater.SOLUTION: A vehicular head lamp 10 includes a housing 70, an outer lens 71 attached to the housing and forming a lamp room S1 between the outer lens and the housing, a lamp unit 20 which is disposed within the lamp room and emits visible light passing through a visible light transmission area A1 of the outer lens, a light probe device 30 which is disposed within the lamp room and emits infrared light passing through an infrared light transmission area A2 of the outer lens, and an infrared light control part 40 which controls the infrared light emitted from the light probe device so that the infrared light emitted from the light probe device illuminates the visible light transmission area of the outer lens.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present disclosure relates to a vehicle headlamp. [Background technology]

[0002] 2. Description of the Related Art There is known a vehicle lamp that removes fogging on an outer lens by providing a line heater in a lamp chamber formed between a housing and an outer lens attached thereto (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2008-21601 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, the vehicle lamp described in Patent Document 1 has a problem in that the line heater causes the inside of the lamp chamber to become hotter than necessary.

[0005] The present disclosure has been made to solve such problems, and has an object to provide a vehicle headlamp that can remove fogging that has adhered to the outer lens without using a heater. [Means for solving the problem]

[0006] The vehicle headlamp according to the present disclosure includes a housing, an outer lens attached to the housing to form a lamp chamber between the housing and the outer lens, a lamp unit disposed within the lamp chamber and emitting visible light that transmits through a visible light transmitting region of the outer lens, an optical probe device disposed within the lamp chamber and emitting infrared light that transmits through an infrared light transmitting region of the outer lens, and an infrared light control unit that controls the infrared light emitted from the optical probe device so that the infrared light emitted from the optical probe device irradiates the visible light transmitting region of the outer lens.

[0007] With this configuration, the fogging on the outer lens 71 can be removed without using a heater.

[0008] This is because the optical probe device is equipped with an infrared light control unit (e.g., an optical deflection element, an optical polarization element driving mechanism) that controls the infrared light emitted from the optical probe device so that the infrared light emitted from the optical probe device irradiates the visible light transmitting area of ​​the outer lens.

[0009] In addition, in the above-mentioned vehicle headlamp, the infrared light control unit includes an optical deflection element and an optical deflection element driving mechanism, and the optical deflection element is configured to deflect the infrared light emitted from the optical probe device and enter the optical deflection element, and the deflected infrared light irradiates the visible light transmitting area of ​​the outer lens, and the optical deflection element driving mechanism may position the optical deflection element at an infrared light incident position on the optical path of the infrared light emitted from the optical probe device or at an infrared light non-incident position outside the optical path of the infrared light emitted from the optical probe device.

[0010] In addition, in the above vehicle headlamp, when the optical deflection element is positioned at the infrared light non-incident position, the optical probe device may emit the infrared light by applying a first driving voltage, and when the optical deflection element is positioned at the infrared light incident position, the optical probe device may emit the infrared light by applying a second driving voltage higher than the first driving voltage.

[0011] In addition, the above-mentioned vehicle headlamp may further include a fogging detection unit that executes a fogging detection process to detect fogging adhering to the outer lens, and the optical deflection element drive mechanism may position the optical deflection element at the infrared light incident position when the fogging is detected, and position the optical deflection element at the infrared light non-incident position when the fogging is not detected.

[0012] In the vehicle headlamp, the infrared light may have a wavelength selected from the group consisting of 895 nm to 915 nm and 1350 nm to 1550 nm.

[0013] In the vehicle headlamp, the optical probe device may include a semiconductor light-emitting element that emits the infrared light, and the semiconductor light-emitting element may be any one of a striped LD, a VCSEL, and a PCSEL.

[0014] In addition, the vehicle headlamp further includes a bracket to which the lamp unit is attached, The lamp may further include an optical axis adjustment mechanism that adjusts an optical axis of the lamp unit by tilting the bracket, and the optical probe device may be attached to the bracket. Effect of the Invention

[0015] The present disclosure makes it possible to provide a vehicle headlamp that can remove fogging that has adhered to an outer lens without using a heater. [Brief description of the drawings]

[0016] [Figure 1] 1 is a schematic configuration diagram of a vehicle lighting system 1 including a vehicle headlamp 10 according to an embodiment. [Diagram 2] FIG. 1 is a front view of a vehicle V on which a vehicle lighting system 1 is mounted. [Diagram 3] 2(a) and 2(b) are cross-sectional views taken along the line AA in FIG. [Figure 4]This is an example of a low beam light distribution pattern PLo formed on a virtual vertical screen (located approximately 25 m forward from the front of the vehicle) facing directly in front of the vehicle. [Diagram 5] 5(a) is a schematic diagram of an optical probe device 30, and (b) and (c) are cross-sectional views taken along the line BB in FIG. 5(a). [Figure 6] 4 is a flowchart of an operation example of the vehicle lighting system 1. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] Hereinafter, a vehicle headlamp 10 according to an embodiment of the present disclosure will be described with reference to the accompanying drawings. In each drawing, corresponding components are given the same reference numerals, and duplicated explanations will be omitted.

[0018] FIG. 1 is a schematic configuration diagram of a vehicle lighting system 1 including a vehicle headlamp 10 according to an embodiment.

[0019] As shown in Fig. 1, the vehicle lighting system 1 includes vehicle headlights 10 (10L, 10R), a detection camera device 50, and a control device 60. The vehicle lighting system 1 is mounted on a vehicle V such as an automobile.

[0020] FIG. 2 is a front view of a vehicle V on which the vehicle lighting system 1 is mounted.

[0021] As shown in FIG. 2, the vehicle headlights 10 (10L, 10R) are provided on both the left and right sides of the front end of the vehicle V.

[0022] 3(a) and 3(b) are cross-sectional views taken along the line AA in FIG.

[0023] As shown in Fig. 1 and Fig. 3(a), a vehicle headlamp 10 includes a lamp unit 20, an optical probe device 30, and an anti-fogging device 40 (an example of an infrared light control unit of the present disclosure). The optical probe device 30 and a detection camera device 50 configure a LiDAR device. The lamp unit 20, the optical probe device 30, and the anti-fogging device 40 are disposed in a lamp chamber S1 formed between a housing 70 and an outer lens 71 attached thereto.

[0024] First, a description will be given of a configuration example of the lighting unit 20. Below, a description will be given of an example in which the lighting unit 20 is a projector type lighting unit.

[0025] As shown in FIG. 3, the lamp unit 20 includes a semiconductor light emitting element 21, a reflecting surface 22 (reflector), a projection lens 23, a reflecting surface 24 (shade / mirror), a bracket 25, an optical axis adjustment mechanism 26, and an extension 27.

[0026] The semiconductor light emitting element 21 is, for example, a white LED light source. The white LED light source has a light emitting surface (for example, 1 mm square). The semiconductor light emitting element 21 is aligned with the first focal point F1 of the reflecting surface 22 when the light emitting surface faces upward. 22 is located nearby.

[0027] The reflecting surface 22 is an ellipsoidal reflecting surface, and has a first focal point F1 on the rear side of the vehicle. 22 , the second focus F2 on the front side of the vehicle 22 The reflective surface 22 is disposed in a state of covering the semiconductor light emitting element 21 (light emitting surface) so that the light emitted from the semiconductor light emitting element 21 is incident on the reflective surface 22.

[0028] The projection lens 23 has a focal point F 23 (rear focal point) is the second focal point F2 of the reflecting surface 22 22 The projection lens 23 projects light reflected from the reflecting surface 22 to a focal point F 23 The light source image formed on the focal plane including the above is inverted and projected forward of the vehicle.

[0029] The reflecting surface 24 (which doubles as a shade and mirror) is located at the focal point F of the projection lens 23. 23 The reflecting surface 24 is a flat reflective surface that includes a front edge disposed nearby and extends horizontally from the front edge toward the rear of the vehicle (the semiconductor light emitting element 21 side). The front edge of the reflecting surface 24 includes a cutoff shape (Z-shaped step portion) (not shown) that corresponds to the cutoff line that is the upper edge of the light distribution pattern for low beam.

[0030] The semiconductor light emitting element 21 , the reflecting surface 22 , the projection lens 23 , and the reflecting surface 24 (which also serves as a shade and mirror) configured as above are attached to a bracket 25 .

[0031] The bracket 25 is attached to the housing 70 in a state in which it can tilt up, down, left, and right. On the other hand, the optical axis adjustment mechanism 26 is, for example, an aiming screw, which is rotatably attached to the housing 70 at the same position. The tip of the aiming screw is screwed into the bracket 25. Therefore, by rotating the aiming screw and adjusting the amount of screwing of the aiming screw into the bracket 25, the bracket 25 tilts up, down, left, and right in accordance with the amount of screwing. This allows the optical axis adjustment (for example, leveling) of the lamp unit 20 to be performed.

[0032] In the vehicle headlamp 10 having the above-described configuration, the semiconductor light emitting element 21 is turned on to generate a low beam light distribution pattern P Lo FIG. 4 shows a low-beam light distribution pattern P formed on a virtual vertical screen (located approximately 25 m ahead of the vehicle) facing the front of the vehicle. Lo This is an example.

[0033] In the lamp unit 20 having the above-mentioned configuration, when the semiconductor light-emitting element 21 is turned on, the light emitted by the semiconductor light-emitting element 21 is reflected by the reflecting surface 22 and reaches the focal point F of the projection lens 23. 23 The optical axis AX of the projection lens 23 23The light is then focused toward the front and exits the projection lens 23 together with the reflected light that is further reflected (back-reflected) by the reflective surface 24 (which serves as a shade and mirror), passes through the visible light transmission area A1 (see Figure 3(a)) of the outer lens 71, and is irradiated forward.

[0034] The light (visible light) that is transmitted through the outer lens 71 (visible light transmitting region A1) and irradiated forward forms a low beam light distribution pattern P Lo This low beam light distribution pattern P Lo In this case, the areas in the vicinity of the cutoff line CL and in the vicinity of the intersection of the H line and the V line are relatively bright, providing excellent distant visibility.

[0035] The visible light transmission area A1 refers to an area of ​​the outer lens 71 through which the light emitted from the lamp unit 20 passes. The light emitted from the lamp unit 20 in the outer lens 71 is reflected by the low beam light distribution pattern P Lo 4) (see the area indicated by the symbol a1 in FIG. 4), or Lo 4. The light may be for forming a part of the high luminous intensity region a2 in FIG. 4, where the luminous intensity is relatively high.

[0036] Next, a configuration example of the optical probe device 30 will be described.

[0037] FIG. 5(a) is a schematic diagram of the optical probe device 30, and FIG. 5(b) is a cross-sectional view taken along line BB of FIG. 5(a).

[0038] 5(a) and 5(b), the optical probe device 30 includes a light source module 31 and a light receiving module 32. The light source module 31 and the light receiving module 32 are housed in a housing 33 having a light-shielding property.

[0039] The light source module 31 emits infrared light of a wavelength belonging to the infrared region of the solar blind band to a measurement target area in front of the vehicle V. The infrared region of the solar blind band is, for example, 895 nm to 915 nm and 1350 nm to 1550 nm. The wavelength belonging to the infrared region of the solar blind band is a wavelength selected from the infrared region of the solar blind band, for example, 905 nm, 940 nm, and 1450 nm. On the other hand, the light receiving module 32 receives reflected light (visible light) that is emitted from the lamp unit 20 (projection lens 23) and reflected (scattered) by the fogging attached to the inside of the outer lens 71 and returns, and outputs an electrical signal according to the received reflected light. The light source module 31 and the light receiving module 32 function as a fogging detection sensor that detects the fogging attached to the inside of the outer lens 71.

[0040] The light source module 31 includes a light source element 31a, an oscillation circuit 31b, and a light exit window 31c.

[0041] The light source element 31a includes a semiconductor laser (semiconductor light-emitting element) that emits (oscillates) infrared light of a wavelength that belongs to the infrared region of the solar blind band, and a diffractive optical element (DOE) that converts the infrared light emitted from the semiconductor laser into a predetermined dot light pattern. The semiconductor laser is, for example, a VCSEL (Vertical Cavity Surface Emitting Laser) that includes an emitter that emits a plurality of laser beams (24×64). The diffractive optical element is, for example, a DOE that is configured with a multi-bend type cell array and multiply branches the infrared light (laser beam) emitted from the VCSEL emitter. The semiconductor laser is not limited to a VCSEL, and may be a stripe LD (Laser Diode) or a PCSEL (Photonic Crystal Surface Emitting Laser). In addition to the diffractive optical element, a rotating mirror (MEMS mirror, galvanometer mirror, polygon mirror) may be used to form the dot light pattern.

[0042] The oscillation circuit 31b receives a control signal from a control device 60 (ECU: Electronic Control Unit) and turns on or off the light source elements 31a in a predetermined pattern (pulse oscillation).

[0043] The light exit window 31c is configured with a filter (for example, a low-pass filter) that transmits the infrared light emitted from the light source element 31a (diffractive optical grating) and blocks external light.

[0044] The light receiving module 32 includes a light receiving element 32a, a detection circuit 32b, and a light receiving window 32c.

[0045] The light receiving element 32a (four-polarized light receiving element) receives reflected light (visible light) that is emitted from the lighting unit 20 (projection lens 23) and reflected (scattered) by the inside of the outer lens 71 (visible light transmitting area A1) or by fogging attached to the inside, and outputs an electrical signal corresponding to the received reflected light.

[0046] The detection circuit 32b is a circuit that converts the electrical signal output by the light receiving element 32a into an electrical signal that can be recognized by the downstream control device 60 (fogging detection unit 65) and transmits the converted electrical signal to the control device 60.

[0047] The light receiving window 32c is configured with a filter (bandpass filter) that transmits reflected light (infrared light) that is emitted from the lighting unit 20 (projection lens 23) and reflected (scattered) by the inside of the outer lens 71 (visible light transmitting area A1) or by fogging attached to the inside and returns, and blocks external light that is not necessary for detection.

[0048] In the optical probe device 30 having the above configuration, the infrared light emitted from the optical probe device 30 (light source element 31a) is converted by a diffractive optical element into a group of laser beams that form a dot pattern in the measurement target area, and is irradiated forward through the infrared light transmission area A2 (see FIG. 3(a)) of the outer lens 71. The angle θ1 in FIG. 3(a) represents the range of the infrared light emitted from the optical probe device 30 (light source element 31a) that transmits through the infrared light transmission area A2 (see FIG. 3(a)) of the outer lens 71.

[0049] Next, a configuration example of the defrosting device 40 will be described.

[0050] In the vehicle headlamp 10 configured as described above, when the outer lens 71 is cooled by rain or the like, condensation occurs and the inside of the outer lens 71 becomes foggy. When the inside of the outer lens 71 becomes foggy, the amount of light (visible light) emitted from the lamp unit 20 that passes through the outer lens 71 (visible light transmission area A1) decreases, so it is desirable to remove the fog that has adhered to the inside of the outer lens 71. The anti-fogging device 40 is used to remove the fog that has adhered to the inside of the outer lens 71.

[0051] 5(a) and 5(b), the antifogging device 40 includes an optical deflection element 41 and an optical deflection element drive mechanism 42. The optical deflection element 41 and the optical deflection element drive mechanism 42 are housed together with the optical probe device 30 in a light-shielding housing 33.

[0052] The optical deflection element 41 is configured to deflect the infrared light (a group of laser beams forming a dot pattern in a measurement target area) emitted from the optical probe device 30 and incident thereon, and the deflected infrared light is configured to irradiate the visible light transmission area A1 of the outer lens 71. Specifically, the optical deflection element 41 is a diffuser.

[0053] The optical deflection element driving mechanism 42 is an actuator that positions the optical deflection element 41 at an infrared light incident position p1 (see Figure 5(c)) on the optical path of the infrared light emitted from the optical probe device 30 or at an infrared light non-incident position p2 (see Figure 5(b)) outside the optical path of the infrared light emitted from the optical probe device 30.

[0054] In the anti-fogging device 40 having the above configuration, when the optical deflection element 41 is disposed at the infrared light incidence position p1 (see FIG. 5(c)), the infrared light (laser beam group forming a dot pattern in the measurement target area) emitted from the optical probe device 30 is deflected by the optical deflection element 41 and irradiates the visible light transmission area A1 of the outer lens 71. At that time, since infrared light is easily absorbed by water, the infrared light (laser beam group forming a dot pattern in the measurement target area) deflected by the optical deflection element 41 and emitted from the optical probe device 30 is absorbed by the fog (water droplets) attached to the inner side of the outer lens 71 (visible light transmission area A1) and heats the fog (water droplets). This causes the fog (water droplets) attached to the inner side of the outer lens 71 (visible light transmission area A1) to evaporate. As a result, the fog (water droplets) attached to the inner side of the outer lens 71 (visible light transmission area A1) can be removed. The wavelength of the infrared light emitted from the optical probe device 30 is preferably in the range of either 895 nm to 915 nm or 1350 nm to 1550 nm. Alternatively, it may be 915 nm to 960 nm, which is at the foot of the absorption band but has a high optical output of the infrared semiconductor light emitting element (infrared laser).

[0055] On the other hand, when the optical deflection element 41 is placed at the infrared light non-incident position p2 (see FIG. 5(b)), the infrared light (a group of laser beams forming a dot pattern in the measurement target area) emitted from the optical probe device 30 passes through the outer lens 71 (infrared light transmitting area A2) and is irradiated toward the measurement target area without being deflected by the optical deflection element 41. This makes it possible to sense an object present in the measurement target area.

[0056] The optical probe device 30 and the anti-fogging device 40 (housing 33) configured as described above are attached to the bracket 25. By attaching the optical probe device 30 and the anti-fogging device 40 (housing 33) to the bracket 25 that is tilted up, down, left and right by the optical axis adjustment mechanism 26 in this manner, the optical axis of the lamp unit 20 can be adjusted by the optical axis adjustment mechanism 26, and the optical axis of the infrared light (a group of laser beams that form a dot pattern in the measurement target area) emitted from the optical probe device 30 can be adjusted.

[0057] Next, the detection camera device 50 will be described.

[0058] The detection camera device 50 is equipped with an imaging element (not shown). The detection camera device 50 captures (receives) the return light emitted from the optical probe device 30 and reflected by an object present in the measurement target area using the imaging element, and generates a distance image whose pixel values ​​are distance values. The detection camera device 50 is provided in the center of the vehicle V in the vehicle width direction inside the passenger compartment, as shown in Fig. 2. The detection camera device 50 captures an image of the area ahead of the vehicle V through the front windshield (wiper sweep area).

[0059] The imaging element is, for example, a single photo counting type imaging element (SPAD: Single Photon Avalanche Diode) capable of measuring the time of flight (direct ToF) of infrared light emitted from the optical probe device 30. Alternatively, a charge distribution type imaging element may be used that detects a phase shift of the optical probe device 30 (indirect ToF) to obtain the distance to the detection target.

[0060] Next, the control device 60 (control ECU) will be described.

[0061] As shown in FIG. 1, a control device 60 (control ECU: Electronic Control Unit) includes a processor (not shown), a storage unit 61, and a memory 62, for example.

[0062] The processor is, for example, a CPU (Central Processing Unit). There may be one processor or multiple processors. The processor functions as an imaging unit 63, a secondary distance image generating unit 64, a fog detection unit 65, and an anti-fogging device control unit 66 by executing a predetermined program (not shown) loaded from a storage unit 61 (for example, a ROM) to a memory 62 (for example, a RAM). Some or all of these may be realized by hardware.

[0063] The imaging unit 63 controls the optical probe device 30 and the detection camera device 50 to capture a right distance image and a left distance image, which are primary distance images. For example, the imaging unit 63 turns on the optical probe device 30 at a predetermined light emission timing and causes the detection camera device 50 to capture an image at a predetermined timing. The right distance image is a distance image captured by the optical probe device 30 provided on the right side of the front end of the vehicle V (the right side when facing the front of the vehicle). On the other hand, the left distance image is a distance image captured by the optical probe device 30 provided on the left side of the front end of the vehicle V (the left side when facing the front of the vehicle).

[0064] The secondary distance image generation unit 64 generates a secondary distance image based on the right distance image and left distance image, which are the primary distance images transmitted from the detection camera device 50. The secondary distance image generated by the secondary distance image generation unit 64 is, for example, a composite distance image obtained by combining the right distance image and the left distance image.

[0065] The fog detection unit 65 executes a fog detection process. The fog detection process is a process for detecting fog attached to the inside of the outer lens 71 based on the output of the light receiving module 32 (light receiving element 32a). For example, the fog detection process is a process for comparing the output of the light receiving module 32 (light receiving element 32a) with a threshold value (for example, stored in the storage unit 61) and determining whether the output of the light receiving module 32 (light receiving element 32a) exceeds the threshold value. When the output of the light receiving module 32 (light receiving element 32a) exceeds the threshold value, the fog detection unit 65 detects fog attached to the inside of the outer lens 71. On the other hand, when the output of the light receiving module 32 (light receiving element 32a) does not exceed the threshold value, the fog detection unit 65 does not detect fog attached to the inside of the outer lens 71.

[0066] The antifogging device control unit 66 controls the optical deflection element drive mechanism 42 (actuator) so that the optical deflection element 41 is disposed at an infrared light incident position p1 (see FIG. 5(c)) on the optical path of the infrared light emitted from the optical probe device 30 or at an infrared light non-incident position p2 (see FIG. 5(b)) outside the optical path of the infrared light emitted from the optical probe device 30. For example, when fogging adhering to the inside of the outer lens 71 is detected, the antifogging device control unit 66 controls the optical deflection element drive mechanism 42 (actuator) so that the optical deflection element 41 is disposed at an infrared light incident position p1 (see FIG. 5(c)) on the optical path of the infrared light emitted from the optical probe device 30. On the other hand, if no fogging is detected on the inside of the outer lens 71, the anti-fogging device control unit 66 controls the optical deflection element driving mechanism 42 (actuator) so that the optical deflection element 41 is positioned at an infrared light non-incident position p2 (see Figure 5 (b)) outside the optical path of the infrared light emitted from the optical probe device 30.

[0067] Next, an example of the operation of the vehicle lighting system 1 having the above configuration will be described.

[0068] FIG. 6 is a flowchart of an operation example of the vehicle lighting system 1.

[0069] First, it is determined whether or not an instruction (for example, an instruction from a user) has been given to turn on or off the vehicle headlamp 10 (step S10). This is realized, for example, by the control device 60 executing a predetermined program.

[0070] Next, if the determination result in step S10 is "ON" (step S10: ON), the vehicle headlamp 10 (semiconductor light-emitting element 21) is turned on (step S11). This is realized, for example, by the control device 60 executing a predetermined program.

[0071] Next, a fogging detection process is executed (step S12). This is realized by the fogging detection unit 65. The fogging detection unit 65 compares the output of the light receiving module 32 (light receiving element 32a) with a threshold value (for example, stored in the storage unit 61), and detects fogging on the inside of the outer lens 71 when the output of the light receiving module 32 (light receiving element 32a) exceeds the threshold value. On the other hand, the fogging detection unit 65 does not detect fogging on the inside of the outer lens 71 when the output of the light receiving module 32 (light receiving element 32a) does not exceed the threshold value.

[0072] Next, if no fogging is detected as a result of step S12 (step S13: NO), the optical deflection element 41 is placed at the infrared light non-incident position p2 (see FIG. 5(b)) (step S14). This is achieved by the anti-fogging device control unit 66. The anti-fogging device control unit 66 controls the optical deflection element drive mechanism 42 (actuator) so that the optical deflection element 41 is placed at the infrared light non-incident position p2 (see FIG. 5(b)) outside the optical path of the infrared light emitted from the optical probe device 30.

[0073] Next, the optical probe device 30 emits infrared light (step S15). Here, since the optical deflection element 41 is disposed at the infrared light non-entering position p2 (see FIG. 5(b)) (see step S14), the infrared light (laser beam group forming a dot pattern in the measurement target area) emitted from the optical probe device 30 is not deflected by the optical deflection element 41, but passes through the outer lens 71 (infrared light transmission area A2) and is irradiated toward the measurement target area. The angle θ1 in FIG. 3(a) and FIG. 5(b) represents the range of the infrared light emitted from the optical probe device 30 (light source element 31a) that passes through the infrared light transmission area A2 (see FIG. 3(a)) of the outer lens 71. This enables sensing of an object present in the measurement target area. In step S15, a first driving voltage corresponding to, for example, a period of 1 μs and a pulse width of 10 nsec is applied to the light source element 31a (semiconductor laser) of the optical probe device 30 by PWM control.

[0074] On the other hand, if fogging is detected as a result of step S12 (step S13: YES), the optical deflection element 41 is placed at the infrared light incident position p1 (see FIG. 5(c)) (step S16). This is achieved by the anti-fogging device control unit 66. The anti-fogging device control unit 66 controls the optical deflection element drive mechanism 42 (actuator) so that the optical deflection element 41 is placed at the infrared light incident position p1 (see FIG. 5(c)) on the optical path of the infrared light emitted from the optical probe device 30.

[0075] Next, the optical probe device 30 emits infrared light (step S17). Here, since the optical deflection element 41 is disposed at the infrared light incidence position p1 (see FIG. 5(c)) (see step S16), the infrared light (a group of laser beams forming a dot pattern in the measurement target area) emitted from the optical probe device 30 is deflected by the optical deflection element 41 and irradiates the visible light transmission area A1 of the outer lens 71. The angle θ2 in FIG. 3(b) and FIG. 5(c) represents the range of the infrared light emitted from the optical probe device 30 (light source element 31a) that irradiates the visible light transmission area A1 of the outer lens 71 (see FIG. 3(b)). At this time, since infrared light is easily absorbed by water, the infrared light (a group of laser beams forming a dot pattern in the measurement target area) emitted from the optical probe device 30 deflected by the optical deflection element 41 is absorbed by the cloudiness (water droplets) attached to the inside of the outer lens 71 (visible light transmission area A1) and heats the cloudiness (water droplets). This causes the cloudiness (water droplets) attached to the inside of the outer lens 71 (visible light transmission area A1) to evaporate. As a result, the cloudiness (water droplets) attached to the inside of the outer lens 71 (visible light transmission area A1) can be removed.

[0076] In step S17, a second driving voltage (effective voltage) higher than the first driving voltage (effective voltage) is applied to the light source element 31a (semiconductor laser) of the optical probe device 30 by PWM control, which corresponds to a duty ratio of, for example, 1 / 10 to 1 / 100. This increases the intensity of the infrared light irradiating the visible light transmission region A1 of the outer lens 71 compared to when the first driving voltage (effective voltage) is applied. This promotes evaporation of the fog (water droplets) attached to the inner side of the outer lens 71 (visible light transmission region A1). As a result, the fog (water droplets) attached to the inner side of the outer lens 71 (visible light transmission region A1) can be quickly removed.

[0077] Thereafter, the above steps are repeatedly executed until fogging is no longer detected in step S13.

[0078] On the other hand, if the determination result in step S10 is "off" (step S10: off), the vehicle headlamp 10 (semiconductor light-emitting element 21) is turned off (step S18). This is realized, for example, by the control device 60 executing a predetermined program.

[0079] Next, the optical deflection element 41 is placed at the infrared light non-incident position p2 (see FIG. 5(b)) (step S19). This is achieved by the anti-fogging device control unit 66. The anti-fogging device control unit 66 controls the optical deflection element drive mechanism 42 (actuator) so that the optical deflection element 41 is placed at the infrared light non-incident position p2 (see FIG. 5(b)) outside the optical path of the infrared light emitted from the optical probe device 30.

[0080] Next, the optical probe device 30 emits infrared light (step S20). Here, since the optical deflection element 41 is disposed at the infrared light non-entering position p2 (see FIG. 5(b)) (see step S19), the infrared light (laser beam group forming a dot pattern in the measurement target area) emitted from the optical probe device 30 is not deflected by the optical deflection element 41, but passes through the outer lens 71 (infrared light transmission area A2) and is irradiated toward the measurement target area. The angle θ1 in FIG. 3(a) and FIG. 5(b) represents the range of the infrared light emitted from the optical probe device 30 (light source element 31a) that passes through the infrared light transmission area A2 (see FIG. 3(a)) of the outer lens 71. This enables sensing of an object present in the measurement target area. In step S20, a first driving voltage corresponding to, for example, a period of 1 μs and a pulse width of 10 nsec is applied to the light source element 31a (semiconductor laser) of the optical probe device 30 by PWM control.

[0081] As described above, according to this embodiment, the fogging on the outer lens 71 can be removed without using a heater.

[0082] This is because the optical probe device is equipped with an infrared light control unit (e.g., an optical deflection element, an optical polarization element driving mechanism) that controls the infrared light emitted from the optical probe device 30 so that the infrared light emitted from the optical probe device 30 irradiates the visible light transmitting area of ​​the outer lens.

[0083] Next, a modified example will be described.

[0084] In the above embodiment, an example in which a projector-type lamp unit is used as the lamp unit 20 has been described, but the present invention is not limited thereto. That is, any lamp unit may be used as long as it transmits light (visible light) for forming a headlamp light distribution pattern (e.g., a low-beam light distribution pattern, a high-beam light distribution pattern, or a light distribution pattern for an adaptive driving beam system (ADB)) through the outer lens 71 (visible light transmission region A1). For example, as the lamp unit 20, a reflector-type lamp unit other than a projector-type lamp unit may be used, a direct projection-type lamp unit may be used, a lamp unit using a light guide (e.g., a light guide rod, a light guide plate), or a lamp unit other than these may be used.

[0085] In the above embodiment, the antifogging device 40 has been described as arranging the optical deflection element 41 at an infrared light incidence position p1 (see FIG. 5(c)) on the optical path of the infrared light emitted from the optical probe device 30 or at an infrared light non-incident position p2 (see FIG. 5(b)) outside the optical path of the infrared light emitted from the optical probe device 30, but the present invention is not limited thereto. For example, the antifogging device 40 may arrange the optical deflection element 41 at an infrared light incidence position on the optical path of the infrared light emitted from an infrared emitting device other than the optical probe device 30 (for example, various infrared emitting devices such as a LiDAR sensor used in a LiDAR device) or at an infrared light non-incident position outside the optical path of the infrared light emitted from the infrared emitting device.

[0086] The numerical values ​​shown in the above embodiments are all examples, and it goes without saying that suitable numerical values ​​different from these can be used.

[0087] The above-described embodiments are merely examples in all respects. The present invention should not be construed as being limited by the description of the above-described embodiments. The present invention can be implemented in various other forms without departing from the spirit or main characteristics thereof. [Explanation of symbols]

[0088] 1. Vehicle lighting system 10...Vehicle headlamp 20…Lamp unit 21...Semiconductor light emitting device 22…Reflective surface 23...Projection lens 24…Reflective surface 25…Bracket 26…Optical axis adjustment mechanism 27…Extension 30...Optical probe device 31...Light source module 31a...light source element 31b…Oscillation circuit 31c…Idemitsu window 32...Light receiving module 32a...Light receiving element 32b…Detection circuit 32c…Light receiving window 33…Housing 40…Anti-fogging device 41...Light deflection element 42...Light deflection element driving mechanism 50...Detection camera device 60...Control device 61...Storage section 62…Memory 63...imaging unit 64...Secondary distance image generation unit 65…Detection section 66...Anti-fogging device control section 70…Housing 71…Outer lens A1…Visible light transmission area A2…Infrared light transmission area AX 23 …optical axis CL: Cutoff line F1 22 …first focus F2 22 …Second focus F 23 …focus F 25 …focus P Lo …Low beam light distribution pattern S1…Light room V…Vehicle p1…infrared light incident position p2…Infrared light non-incident position

Claims

1. Housing and an outer lens attached to the housing to form a lamp chamber between the housing and an outer lens; A lamp unit is disposed in the lamp chamber and emits visible light that passes through a visible light transmitting region of the outer lens; An optical probe device disposed in the lamp chamber and configured to emit infrared light that passes through an infrared light transmitting region of the outer lens; and an infrared light control unit that controls the infrared light emitted from the optical probe device so that the infrared light emitted from the optical probe device irradiates the visible light transmitting region of the outer lens.

2. the infrared light control unit includes an optical deflection element and an optical deflection element drive mechanism; the optical deflection element is configured to deflect infrared light emitted from the optical probe device and incident on the optical deflection element, and the deflected infrared light is configured to irradiate the visible light transmitting region of the outer lens; 2. The vehicle headlamp according to claim 1, wherein the optical deflection element driving mechanism positions the optical deflection element at an infrared light incident position on the optical path of the infrared light emitted from the optical probe device or at an infrared light non-incident position outside the optical path of the infrared light emitted from the optical probe device.

3. When the optical deflection element is disposed at the infrared light non-entering position, the optical probe device emits the infrared light by applying a first drive voltage thereto; 3. The vehicle headlamp according to claim 2, wherein the optical deflection element is disposed at the infrared light incident position, and the optical probe device emits the infrared light by applying a second drive voltage higher than a first drive voltage.

4. A fog detection unit that executes a fog detection process to detect fog attached to the outer lens is further provided.

3. The vehicle headlamp according to claim 2, wherein the optical deflection element drive mechanism disposes the optical deflection element at the infrared light incident position when the fogging is detected, and disposes the optical deflection element at the infrared light non-incident position when the fogging is not detected.

5. 2. The vehicle headlamp according to claim 1, wherein the wavelength of the infrared light is selected from the group consisting of 895 nm to 960 nm and 1350 nm to 1550 nm.

6. the optical probe device includes a semiconductor light emitting element that emits the infrared light, The vehicle headlamp according to claim 1 , wherein the semiconductor light emitting element is any one of a stripe LD, a VCSEL, and a PCSEL.

7. A bracket to which the lamp unit is attached; and an optical axis adjustment mechanism for adjusting an optical axis of the lamp unit by tilting the bracket. The vehicle headlamp according to claim 1 , wherein the optical probe device is attached to the bracket.

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