JP5819153B2 - Vehicle headlamp device - Google Patents

Description

  The present invention relates to a vehicle headlamp device.

  As this type of device, a device using a plurality of light emitting elements (for example, light emitting diodes) forming an array as a light source is known. An irradiation range defined as a light distribution pattern formed by light emitted from all light sources is divided into a plurality of partial areas, and at least one of the plurality of light emitting elements is assigned to each partial area. By independently turning on and off each light emitting element, at least one of a plurality of partial regions constituting the irradiation range can be selectively brought into an irradiation state or a non-irradiation state (see, for example, Patent Document 1).

  By using this technique, a swivel mechanism that turns the light distribution direction of the lamp unit to the left and right can be omitted. In other words, the swivel mechanism mechanically rotates the lamp unit to move the light distribution direction (the direction of the lamp optical axis) to the left and right, whereas in the technique using the light emitting element array, the irradiation state and non-irradiation of each partial area By turning on and off each light emitting element so as to switch the state as appropriate, the partial area in the irradiation state is swiveled to the left and right within the irradiation range to change the light distribution direction.

JP 2009-218155 A

  When a swivel mechanism that mechanically turns the lamp unit is used, the illumination range itself moves to the left and right, so the illuminance in the illumination area does not change before and after the movement. However, when the swivel mechanism is omitted and the electronic swivel control using the light emitting element array is used, the direction of the light emitting element array does not change, so the irradiation range itself does not move, and only the irradiation region moves within the irradiation range. . For this reason, a situation may occur in which the predetermined irradiation area does not fit within the irradiation range.

  For example, in a situation where the right end portion of the irradiation range is an irradiation region, when the swivel movement is further performed to the right side, a part of the irradiation region goes out of the right end of the irradiation range. Therefore, only a part of the region that should be irradiated originally is located within the irradiation range and is irradiated by the light emitting element, and the illuminance is lower than that before the swivel movement of the irradiation region.

  The present invention has been made in order to solve at least a part of the above-described problems, and a technique capable of suppressing a decrease in illuminance in an irradiation region during a swivel operation while using a light emitting element array that can omit a swivel mechanism as a light source. The purpose is to provide.

  In order to solve at least a part of the above problems, one aspect that the present invention can take is a vehicle headlamp device, which includes a plurality of light sources for a headlamp disposed in a vehicle, and the plurality of light sources. Control means for controlling the light irradiation to form a predetermined irradiation area within an irradiation range including a plurality of partial areas, and the control means swivels the irradiation area within the irradiation range. When performing the control, the difference in illuminance between the adjacent partial areas included in the irradiation area is changed before and after the swivel movement.

  According to such a configuration, the illuminance distribution in the irradiation area can be changed before and after the swivel movement of the irradiation area.

  The illuminance distribution is changed by controlling the illuminance of the predetermined partial area in the irradiation area after the swivel movement to be higher than the illuminance of the partial area corresponding to the predetermined partial area in the irradiation area before the swivel movement. Should be done.

  The control means may be configured to perform the control so that the illuminance of the irradiation area is substantially the same before and after the swivel movement. According to such a configuration, it is possible to suppress the driver's recognition that the irradiation destination has become dark.

  The control means may be configured to perform the control so that the amount of increase in the illuminance increases as the partial area is closer to the driver's gaze estimation position. According to such a configuration, forward visibility by the driver can be further improved.

  The storage device further stores in advance a plurality of irradiation patterns having different illuminance distributions in the illuminance area after the movement, and the control means selects one of the irradiation patterns according to the traveling state of the vehicle. May be. According to such a configuration, the processing load of the control means can be suppressed.

  The plurality of light sources are preferably used as high beam light sources.

  According to the present invention, the swivel mechanism that mechanically rotates the lamp optical axis is omitted to reduce the size and weight of the lamp unit, while minimizing the decrease in illuminance in the irradiation area due to the electronic swivel control, The front visibility of the person can be ensured.

1 is a diagram schematically illustrating an overall configuration of a vehicle on which a headlight device according to a first embodiment of the present invention is mounted. It is a horizontal sectional view which shows the structure of the right headlamp unit in FIG. It is a figure which shows typically the structure of the light emitting element unit in FIG. It is a figure which shows typically the light distribution pattern formed with the light from the headlamp apparatus in FIG. It is a figure explaining the light control by the headlamp apparatus of FIG. It is a figure explaining the light control by the headlamp apparatus which concerns on the 2nd Embodiment of this invention. It is a figure which shows typically the structure of the light emitting element unit in the headlamp apparatus which concerns on the 3rd Embodiment of this invention, and the light distribution pattern formed with the light from the said headlamp apparatus.

  The present invention will be described in detail below with reference to the accompanying drawings. In each drawing used in the following description, the scale is appropriately changed to make each member a recognizable size.

  FIG. 1 schematically shows the overall configuration of a vehicle 10 equipped with a headlamp control system 11 according to a first embodiment of the present invention. The headlamp control system 11 includes a headlamp device 12, an integrated control unit 14, a wheel speed sensor 16, a steering angle sensor 17, a camera 18, and a navigation system 19.

  The integrated control unit 14 includes a CPU that executes various arithmetic processes, a ROM that stores various control programs, a RAM that is used as a work area for data storage and program execution, and executes various controls in the vehicle 10. .

  The wheel speed sensor 16 is provided corresponding to each of the four wheels of the left and right front wheels and the rear wheel assembled to the vehicle 10. Each of the wheel speed sensors 16 is communicably connected to the integrated control unit 14 and outputs a signal corresponding to the rotational speed of the wheel to the integrated control unit 14. The integrated control unit 14 calculates the speed of the vehicle 10 using the signal input from the wheel speed sensor 16.

  The steering angle sensor 17 is provided on the steering wheel and is communicably connected to the integrated control unit 14. The steering angle sensor 17 outputs a steering angle pulse signal corresponding to the steering rotation angle of the steering wheel by the driver to the integrated control unit 14. The integrated control unit 14 calculates the traveling direction of the vehicle 10 using the signal input from the steering angle sensor 17.

  The camera 18 includes an imaging device such as a CCD (Charged Coupled Device) sensor or a CMOS (Complementary Metal Oxide Semiconductor) sensor, and shoots the front of the vehicle to generate image data. The camera 18 is communicably connected to the integrated control unit 14, and the generated image data is output to the integrated control unit 14.

  The navigation system 19 is communicably connected to the integrated control unit 14 and outputs information indicating the location where the vehicle 10 is traveling to the integrated control unit 14.

  The headlamp device 12 includes a headlamp controller 20, a right headlamp unit 22R, and a left headlamp unit 22L. Hereinafter, the right headlamp unit 22R and the left headlamp unit 22L are collectively referred to as the headlamp unit 22 as necessary. The headlamp control unit 20 includes a CPU, a ROM, a RAM, and the like, and controls light irradiation by the headlamp unit 22. The headlamp control unit 20 functions as at least a part of the control means in the present invention.

  FIG. 2 shows a cross section of the right headlamp unit 22R as viewed from above by cutting along the horizontal plane. The right headlamp unit 22R includes a translucent cover 30, a lamp body 32, an extension 34, a first lamp unit 36, and a second lamp unit 38.

  The translucent cover 30 is made of a translucent resin or the like. The translucent cover 30 is attached to the lamp body 32 to define a lamp chamber. The first lamp unit 36 and the second lamp unit 38 are disposed in the lamp chamber.

  The extension 34 has an opening for allowing irradiation light from the first lamp unit 36 and the second lamp unit 38 to pass therethrough, and is fixed to the lamp body 32. The first lamp unit 36 is disposed on the vehicle outer side than the second lamp unit 38.

  The first lamp unit 36 is a so-called parabolic lamp unit, and forms a low beam light distribution pattern to be described later. The first lamp unit 36 uses an incandescent lamp having a filament such as a halogen lamp or a high intensity discharge (HID) lamp such as a metal halide lamp as the light source 42. Since the structure of the 1st lamp unit 36 is well-known, detailed description is abbreviate | omitted.

  The second lamp unit 38 includes a holder 46, a projection lens 48, a light emitting element unit 49, a substrate 50, and a heat sink 54.

  The projection lens 48 is attached to one opening of a holder 46 formed in a cylindrical shape. The projection lens 48 is a plano-convex aspheric lens having a convex front surface and a flat rear surface, and projects a light source image formed on the rear focal plane onto a virtual vertical screen in front of the lamp as a reverse image. .

  The light emitting element unit 49 is provided on the front surface of the substrate 50, and the heat sink 54 is provided on the rear surface of the substrate 50. The heat sink 54 is formed in a shape having a large number of heat radiation fins from a metal such as aluminum.

  FIG. 3 shows a configuration of the light emitting element unit 49 as viewed from the front of the vehicle. The light emitting element unit 49 includes a lower light emitting element array 52L and an upper light emitting element array 52U mounted on the substrate 50.

  The lower light emitting element array 52L includes first lower light emitting elements 52L-1 to thirteenth lower light emitting elements 52L-13 arranged from the right side to the left side of the vehicle. The upper light emitting element array 52U includes first upper light emitting elements 52U-1 to thirteenth upper light emitting elements 52U-13 arranged from the right side to the left side of the vehicle.

  Each light emitting element is formed in a rectangular parallelepiped shape having the same height and the same width. Although not shown, each light emitting element has a light source and a thin film. The light source is a white LED (light emitting diode) having a light emitting surface of about 1 mm square, and the thin film is provided so as to cover the light emitting surface.

  In FIG. 3, each light emitting element is numbered and other than the first lower light emitting element 52L-1, the thirteenth lower light emitting element 52L-13, the first upper light emitting element 52U-1, and the thirteenth upper light emitting element 52U-13. Reference numerals are omitted for the light emitting elements. For example, the light emitting element numbered 7 in the lower light emitting element array 52L means the seventh lower light emitting element 52L-7, and the light emitting element numbered 12 in the upper light emitting element array 52U is the twelfth upper side light emitting element array 52U. The light emitting element 52U-12 is meant.

  Each light emitting element forms a current circuit with the headlamp control unit 20 via a control line 53. In FIG. 3, control lines are used for light emitting elements other than the first lower light emitting element 52L-1, the thirteenth lower light emitting element 52L-13, the first upper light emitting element 52U-1, and the thirteenth upper light emitting element 52U-13. Illustration of 53 is omitted. The headlamp control unit 20 can control the light intensity when the light emitting elements are turned on and off by adjusting the amount of current supplied through the control line 53.

  As shown in FIG. 2, the substrate 50 is mounted in the other opening of the holder 46, whereby the light emitting element unit 49 is disposed inside the holder 46. Each of the plurality of light emitting elements included in the light emitting element unit 49 emits light, whereby each image is projected onto a virtual vertical screen in front of the lamp. The plurality of light emitting elements function as a plurality of light sources in the present invention.

  The left headlight unit 22L is configured symmetrically with the right headlight unit 22R, and a detailed description thereof is omitted. Also in the right headlamp unit 22R, the first lower light emitting element 52L-1 to the thirteenth lower light emitting element 52L-13 and the first upper light emitting element 52U-1 to the thirteenth upper light emitting element 52U-13 are arranged on the right side of the vehicle. To the left side of the vehicle. That is, regarding the internal configuration of the second lamp unit 38, the left headlamp unit 22L and the right headlamp unit 22R are not symmetrical.

  FIG. 4A shows a light distribution pattern formed on a virtual vertical screen disposed, for example, at a position 25 m ahead of the vehicle by light irradiated forward from the right headlight unit 22R and the left headlight unit 22L. Show.

  The low beam light distribution pattern PL is formed by combining irradiation light from the first lamp unit 36 of the right headlamp unit 22R and the left headlamp unit 22L. The low beam light distribution pattern PL is a left light distribution pattern for low beam, and has a first cut-off line CL1 to a third cut-off line CL3 at the upper end edge thereof. The first cut-off line CL1 to the third cut-off line CL3 extend in the horizontal direction at the left and right steps with a VV line as a boundary passing through the vanishing point in the lamp front direction.

  The first cut-off line CL1 is used as an oncoming lane cut-off line. The third cutoff line CL3 extends obliquely from the left end of the first cutoff line CL1 toward the upper left. The second cutoff line CL2 extends on the HH line on the left side from the intersection of the third cutoff line CL3 and the HH line. That is, the second cut-off line CL2 is used as the own lane side cut-off line.

  In the low beam light distribution pattern PL, a hot zone HZ that is a high luminous intensity region is formed so as to surround an elbow point E that is an intersection of the first cutoff line CL1 and the VV line slightly to the left.

  The additional light distribution pattern PA corresponds to the irradiation range in the present invention, and is a light distribution pattern formed by irradiation light from all the light emitting elements included in the second lamp unit 38 of the right headlamp unit 22R and the left headlamp unit 22L. Defined. The additional light distribution pattern PA includes a horizontal line (HH line), and is formed in a strip shape extending in the horizontal direction so that the lower end is positioned on the first cut-off line CL1. Therefore, the second lamp unit 38 may function as a high beam light source.

  FIG. 4B shows the relationship between the additional light distribution pattern PA, the lower light emitting element array 52L, and the upper light emitting element array 52U. In this example, the additional light distribution pattern PA is divided into 26 partial regions each having substantially the same shape and area, and includes upper partial regions U1 to U13 and lower partial regions L1 to L13. The lower partial areas L1 to L13 are located in the vicinity of the HH line, and the upper partial areas U1 to U13 are located above the lower partial areas L1 to L13.

  The lower partial region L1 is formed as a composite of projection images using the first lower light emitting element 52L-1 of the right headlight unit 22R and the first lower light emitting element 52L-1 of the left headlight unit 22L as light source images. The In other words, it is formed by synthesizing irradiation light from these light emitting elements. Similarly, the other partial areas are formed by synthesizing irradiation light from the corresponding light emitting elements of the left and right headlamp units 22.

  For example, the lower partial region L9 is formed by combining irradiation light from the left and right ninth lower light emitting elements 52L-9. The upper partial region U11 is formed by combining irradiation light from the left and right eleventh upper light emitting elements 52U-11. Since the irradiation light from each light emitting element passes through the projection lens 48, the arrangement of the partial areas and the arrangement of the light emitting elements shown in FIG.

  Next, dimming control by the headlamp control system 11 having the above configuration will be described with reference to FIG.

  The headlamp control system 11 according to the present embodiment follows the change in the steering angle of the vehicle 10 and moves the irradiation area of the headlamp horizontally and horizontally in the additional light distribution pattern PA to irradiate the steering destination. Control operations are possible.

  Based on the signals input from the wheel speed sensor 16 and the steering angle sensor 17, the integrated control unit 14 increases or decreases the amount of current that flows to each light emitting element of the left and right headlight units 22 through the headlight control unit 20. To change the luminous intensity of the irradiation light. Thereby, the illuminance of each partial region is adjusted, and the illuminance distribution in the additional light distribution pattern PA changes. By appropriately performing this adjustment, the irradiation area, which is a set of partial areas that are in the irradiation state, moves horizontally in the horizontal direction in the additional light distribution pattern PA, and the lamp optical axis of each headlamp unit 22 is mechanically moved. The same effect as that of the swivel mechanism that pivots automatically can be obtained.

  (A) of FIG. 5 is a figure which shows the illumination intensity distribution of the lower side partial area | regions L1-L13 in the additional light distribution pattern PA in a certain initial irradiation state. The longer the bar graph, the higher the illuminance. In addition, since the illuminance of each partial area and the amount of current supplied to the light emitting element that irradiates light to the partial area have a corresponding relationship, the figure shows the current supplied to the light emitting element corresponding to each partial area The value is also shown, and the longer the bar graph, the larger the value of the supplied current.

  That is, in the initial irradiation state described above, the irradiation region is formed so that the vicinity of the elbow point E is irradiated brightest, and the illuminance decreases as the distance from the elbow point E increases in the horizontal direction.

  FIG. 5B is a diagram illustrating a case where electronic swivel control is performed to move the irradiation area to the right in the additional light distribution pattern PA when the vehicle 10 turns from the initial irradiation state. . The partial area with the highest illuminance in the irradiation area is swiveled from L7 to L12 according to the turning of the vehicle 10 or the like, and light irradiation is performed so that a predetermined position at the steering destination has the highest illuminance.

  Unlike the swivel mechanism that mechanically swivels the lamp optical axis of the lamp unit, the additional light distribution pattern PA itself does not move left and right in the electronic swivel control. Therefore, the irradiation area is moved to the right while maintaining the illuminance distribution in the irradiation area from the state shown in FIG. 5A, in other words, while maintaining the illuminance difference between the adjacent partial areas included in the irradiation area. Then, as shown by the white portion of the bar graph in FIG. 5B, a part of the irradiation region (portion corresponding to the initial lower partial regions L9 to L13) protrudes from the right end of the additional light distribution pattern PA. End up.

  As a result, the portion included in the initial lower partial regions L9 to L13 in the irradiation region cannot be irradiated with light by the light emitting element, so that the illuminance of the entire irradiation region is reduced. The driver perceives that the illuminance at the front steering destination has decreased after the electronic swivel operation has been performed.

  Therefore, in the present embodiment, in view of the characteristics of the light emitting element array that the light intensity of each light emitting element can be controlled independently, the amount of decrease in illuminance due to swivel movement of the irradiation area is assigned to another partial area, and Control is performed to increase the illuminance and maintain the illuminance of the entire irradiation area.

  The total area of the hatched portion in FIG. 5B corresponds to the total area of the bar graph in the lower partial regions L9 to L13 shown in FIG. Since a part of the irradiation area corresponding to the partial area cannot be irradiated after the irradiation area is moved by the electronic swivel, the illuminance of the entire illuminance area is lowered accordingly.

  In the dimming control of the present embodiment, this reduced amount is appropriately distributed and assigned to the lower partial areas L5 to L11, whereby the illuminances of the lower partial areas L5 to L11 are increased only by hatched portions. As a result, the illuminance distribution in the irradiation region after the swivel movement is obtained by adding the shaded portion to the white portion. Since the illuminance before movement is maintained in the entire irradiation region, it is possible to suppress the driver's recognition that the irradiation destination has become dark.

  When execution of the electronic swivel control is instructed from the integrated control unit 14, the swivel movement is performed in the additional light distribution pattern PA by an amount corresponding to a desired swivel angle while maintaining the illuminance distribution of the current irradiation region. A difference in illuminance of the entire irradiation area before and after movement is obtained. Specifically, the total amount of current for driving the light emitting element that irradiates light to the partial area included in the current irradiation area and the light emitting element necessary for forming the virtual irradiation area after the swivel movement are driven. The headlamp control unit 20 calculates a difference from the total amount of current to be performed.

  When the difference is zero, it means that the entire virtual irradiation area after the swivel movement is still within the additional light distribution pattern PA. In this case, since no special additional processing is required, the first lower light emission corresponding to each of the lower partial regions L1 to L13 so that the current irradiation region swivels within the additional light distribution pattern PA by a predetermined amount. Turning on and off the light of the element 52L-1 to the thirteenth lower light emitting element 52L-13 is controlled.

  If there is a difference, it means that a part of the virtual irradiation area after the swivel movement has gone out of the additional light distribution pattern PA as shown in FIG. 5B. In the case of this example, the current amount for driving the light emitting element that irradiates the lower partial regions L9 to L13 among the current irradiation region shown in FIG. 5A is calculated as a difference. .

  The headlamp control unit 20 determines the actual illuminance distribution of the irradiation area after swivel movement based on the amount of current calculated as the difference. Specifically, the irradiation current after swivel movement is increased by increasing the drive current of the light emitting element corresponding to another partial region located in the additional light distribution pattern PA by an amount appropriately allocated the calculated differential current amount. It is set as the drive current of each light emitting element which forms a region.

  In the example of FIG. 5B, the shaded portion of the bar graph corresponds to the amount of drive current increased by the above processing. The current amount for driving the light emitting elements that irradiate the lower partial regions L9 to L13 in the current irradiation region shown in FIG. 5A is the light emission that irradiates the lower partial regions L5 to L11. It is distributed and added as the drive current of the element.

  The headlamp control unit 20 includes first lower light emitting elements 52L-1 to 52L-1 corresponding to the lower partial regions L1 to L13 so that the illuminance region after swivel movement has the illuminance distribution determined as described above. Controls turning on and off of the thirteenth lower light emitting element 52L-13.

  That is, in the present embodiment, when performing control to swivel move a predetermined irradiation area in the additional light distribution pattern PA, the difference in illuminance between adjacent partial areas included in the irradiation area is determined by swivel movement. The illuminance distribution is changed by changing it before and after. It is only necessary that at least one such adjacent partial region is included in the irradiation region after the swivel movement.

  In other words, control is performed so that the illuminance of the predetermined partial area in the irradiation area after the swivel movement is higher than the illuminance of the partial area corresponding to the predetermined partial area in the irradiation area before the swivel movement.

  For example, the lower partial region L10 in the irradiation region after swivel movement shown in (b) of FIG. 5 corresponds to the lower partial region L5 in the irradiation region before swivel movement shown in (a) of FIG. The illuminance of the lower partial area L10 after the swivel movement is higher than the illuminance of the lower partial area L5 before the swivel movement. It is only necessary that at least one such partial region is included in the irradiation region after the swivel movement.

  As long as the above control guidelines are followed, the method of distributing the differential current amount can be determined as appropriate. In the above example, the amount of difference current is allotted to light emitting elements corresponding to different partial areas so that the illuminance of the entire irradiation area substantially matches before and after swivel movement. At least a part of the current amount may be provided for additional distribution. Further, if the change in the light distribution is temporary, an amount exceeding the difference current amount may be provided for additional distribution.

  The distribution of the differential current amount may be equally added to each light emitting element that irradiates light to a partial region that forms the irradiation region after movement. Further, as shown in FIG. 5B, a different amount of current may be added for each light emitting element.

  When a different amount of current is additionally distributed for each light emitting element, control may be performed so that the amount of increase in illuminance increases in a partial region closer to the driver's line-of-sight position estimated by the integrated control unit 14.

  For example, in FIG. 5B, it is estimated that the driver's line-of-sight position is in the vicinity of the lower partial region L9. For this reason, the amount of increase in drive current is controlled so as to approach the lower partial region L9. In this case, since the illuminance distribution in the irradiation area after movement is determined so that the vicinity of the driver's line-of-sight estimated position is irradiated brighter, forward visibility by the driver can be further improved.

  Like the lower partial region L5 in FIG. 5B, the differential current also flows in the partial region (originally non-irradiated partial region) corresponding to the partial region that was not included in the irradiated region before the swivel movement. A part of the quantity may be distributed. In addition, the distribution of the differential current amount is performed so that the illuminance is increased only in the partial area corresponding to the partial area included in the irradiation area before the swivel movement (only the lower partial areas L6 to L13 in FIG. 5B). May be determined.

  In the above example, the headlamp control unit 20 calculates the difference in the total current amount for driving the light emitting elements before and after the movement of the irradiation region by calculation, and based on this, the illuminance distribution (driving) of the irradiation region after the swivel movement (Additional distribution of current) is determined. However, a plurality of irradiation patterns having different illuminance distributions in the irradiation area after swivel movement are stored in advance according to the assumed driving state of the vehicle 10 and the vehicle driving state detected by the integrated control unit 14 It is good also as a structure which selects any one irradiation pattern according to etc. In this case, the processing load of the headlamp control unit 20 can be suppressed.

  The upper light emitting elements 52U-1 to 52U-13 that irradiate the upper partial areas U1 to U13 shown in FIG. 4B are similar to the lower light emitting elements 52L-1 to 52L-13 described above. Since it can be controlled, detailed description is omitted. The upper light emitting element array 52U and the lower light emitting element array 52L may perform drive control so as to correlate, or may perform drive control independently.

  The integrated control unit 14 performs processing for determining the illuminance distribution in the irradiation area after the swivel movement, and outputs a command indicating the turning on / off of each light emitting element and the light intensity corresponding to the determination result to the headlamp control unit 20. It is good also as a structure. In this case, the headlamp control unit 20 controls supply / cutoff of the current flowing through each light emitting element based on the command.

  The electronic swivel control described above can also be applied to spot irradiation of pedestrians detected in the additional light distribution pattern PA. For example, the integrated control unit 14 analyzes the image data input from the camera 18 and determines the presence or absence of a pedestrian in front of the vehicle. When it is determined that such a pedestrian exists, the integrated control unit 14 outputs position data indicating the position of the pedestrian obtained by analyzing the image data to the headlamp control unit 20.

  In addition to or instead of the image data input from the camera 18, the presence of a pedestrian may be specified using obstacle data acquired by a front sensor such as a laser sensor (not shown).

  The headlamp control unit 20 identifies a partial area in the additional light distribution pattern PA that includes the position of the pedestrian indicated by the position data, and turns on the light emitting element corresponding to the partial area. As a result of spot irradiation of the pedestrian, the pedestrian can be informed of the existence of the vehicle effectively, and the driver can surely see the pedestrian.

  When the relative position with the pedestrian changes as the vehicle turns, the irradiation area needs to be swiveled within the additional light distribution pattern PA in order to maintain the state in which the pedestrian is irradiated. Under this circumstance, at least a part of the irradiation area may come out of the additional light distribution pattern PA.

  For example, when a part of the irradiation area after swivel movement comes out from the left end of the additional light distribution pattern PA, the illuminance of the irradiation area decreases by an amount corresponding to that part, and the total amount of current driving the light emitting element decreases. To do. For example, the decrease in illuminance can be compensated to some extent by adding this decrease to the drive current of the light emitting element that irradiates light to the partial regions L1 and U1 located at the left end of the additional light distribution pattern PA.

  The electronic swivel control can be switched between valid and invalid by the driver's operation. Further, the integrated control unit 14 may determine necessity based on the vehicle position information acquired by the navigation system 19 and may automatically enable / disable switching.

  As described above, according to the dimming control of this embodiment, the swivel mechanism that mechanically rotates the lamp optical axis is omitted, and the lamp unit is reduced in size and weight, and the irradiation associated with the electronic swivel control is performed. It is possible to minimize a decrease in illuminance in the region and to ensure the driver's forward visibility.

  Next, a second embodiment of the present invention will be described with reference to FIG. The present embodiment is different from the first embodiment in the dimming control performed by the integrated control unit 14 and the headlamp control unit 20. Since the other configuration of the headlamp control system 11 is the same as that of the first embodiment, detailed description thereof is omitted.

  The dimming control of the present embodiment relates to the above-described spot irradiation of a pedestrian. When a pedestrian is detected in the additional light distribution pattern PA by the camera 18 or the like, light is locally irradiated on a partial region where the pedestrian is located. Since this spot irradiation is performed with light having a relatively high luminous intensity, a current supplied to drive a light emitting element that emits light increases. Therefore, when a plurality of pedestrians are detected and it becomes necessary to spot-irradiate each pedestrian, the rated current value that can be supplied to the light emitting element array may be exceeded.

  The dimming control of the present embodiment is for preventing the current supplied to the light emitting element array from exceeding the rated value while enabling spot irradiation for a plurality of pedestrians.

  FIG. 6A is a diagram illustrating the illuminance distribution of the lower partial regions L1 to L13 when two pedestrians detected in the additional light distribution pattern PA are spot-irradiated. The first pedestrian has received spot irradiation at positions corresponding to the lower partial areas L3 and L4, and the second pedestrian has received spot irradiation at positions corresponding to the lower partial areas L8 and L9.

  FIG. 6B is a diagram showing the relationship between the amount of current supplied to the light emitting element that performs the spot irradiation and the amount of current supplied to the entire light emitting element array. The lower row shows the total amount of current supplied to the light emitting elements that irradiate the lower partial regions L3 and L4, and the middle row shows the total amount of current supplied to the light emitting elements that irradiate the lower partial regions L8 and L9. The upper row shows the total amount of current supplied to the entire lower light emitting element array 52L. T indicates a rated current value that can be supplied to the lower light emitting element array 52L.

  In the dimming control of the present embodiment, when there are a plurality of areas where spot irradiation is performed, the light emitting elements that irradiate light to each area are alternately turned on and off. In the example shown in FIG. 6B, when the light emitting elements that emit light to the lower partial regions L3 and L4 are turned on, the light emitting elements that emit light to the lower partial regions L8 and L9 are turned off. When the light emitting elements that irradiate the lower partial areas L3 and L4 are turned off, the light emitting elements that irradiate the lower partial areas L8 and L9 are turned on.

  By performing on / off control in this way, the current supplied to the light emitting element that irradiates each spot irradiation region is set to the rated current value T of the lower light emitting element array 52L while ensuring the illuminance, and spot irradiation is performed. The amount of current supplied to the lower light emitting element array 52L during the execution of the operation does not exceed the rated value T.

  When the switching frequency between the plurality of spot irradiation regions, that is, the light-on / off frequency of the light emitting element corresponding to each spot irradiation region is increased to some extent, the illuminance of each spot irradiation region is lowered and viewed by the driver. Therefore, in the present embodiment, the lighting frequency is set to less than 30 Hz and 4 Hz or more. Thereby, the pedestrian located in each spot irradiation area can be visually recognized with sufficient brightness.

  When the number of pedestrians to perform spot irradiation increases, the period in which each pedestrian is repeatedly subjected to irradiation has to be long. In that case, an upper limit may be set for the number of areas to be spot-irradiated, and spot irradiation may be performed preferentially from a pedestrian with a high degree of danger.

  Specifically, the priority of pedestrians detected in the own lane is set to the highest, and then the priority is set lower in the order of pedestrians entering the lane from the road shoulder and then pedestrians detected on the road shoulder. . The positions of these pedestrians are determined by the integrated control unit 14 analyzing image data input through the camera 18 or the like.

  As described above, according to the light control of this embodiment, even when a plurality of areas that require spot irradiation are detected in the additional light distribution pattern PA, the illuminance of each spot irradiation area is maximized. The current supplied to the light emitting element array can be controlled so as not to exceed the rated current value.

  The target for spot irradiation is not limited to pedestrians. Obstacles such as vehicles parked on the road shoulder can be included as appropriate in the irradiation target.

  Next, a third embodiment of the present invention will be described with reference to FIG. In the present embodiment, the configuration of the light emitting element unit 49a included in the second lamp unit 38 is different from that of the light emitting element unit 49 in the first embodiment. Since the other configuration of the headlamp control system 11 is the same as that of the first embodiment, detailed description thereof is omitted.

  In the additional light distribution pattern PA shown in FIG. 4B, the upper partial areas U1 to U13 need to be subjected to finer light distribution control than the lower partial areas L1 to L13 including the vicinity of the HH line. Is low. In other words, the upper side of the additional light distribution pattern PA can be configured with a smaller number of partial regions. However, if the number of light emitting elements is reduced so as to correspond to the reduced partial areas, the illuminance of each partial area is reduced or the light distribution area is insufficient.

  Therefore, the light emitting element unit 49a in the present embodiment is configured to reduce the number of partial regions where light distribution can be controlled while ensuring illuminance without reducing the number of light emitting elements.

  FIG. 7A shows a configuration in which the light emitting element unit 49a is viewed from the front of the vehicle. The light emitting element unit 49a includes a lower light emitting element array 52L and an upper light emitting element array 52Ua mounted on the substrate 50. Since the lower light emitting element array 52L has the same configuration as that of the first embodiment, detailed description thereof is omitted.

  FIG. 7B shows an additional light distribution pattern PA 'formed by the light emitting element unit 49a of the present embodiment. The lower side of the pattern is divided into 13 partial areas L1 to L13, while the upper side is divided into 6 partial areas U13, U45, U6, U78, U910, and U1113.

  In order to irradiate each of the upper partial regions divided as described above, some of the plurality of light emitting elements constituting the upper light emitting element array 52Ua of the present embodiment are connected in series by a control line 53a. .

  In the example shown in FIG. 7B, the upper partial region U13 has an area corresponding to the lower partial regions L1 to L3. In order to irradiate light on the upper partial region U13, the three upper light emitting elements 52U-1 to 52U-3 are connected in series by the control line 53a and are simultaneously turned on and off. In order to irradiate the upper partial region U13 having an area corresponding to the lower partial regions L1 to L3 with the same number of upper light emitting elements as the lower light emitting elements that irradiate light to the lower partial regions L1 to L3, Illuminance does not decrease.

  Similarly, the upper partial region U45 having an area corresponding to the lower partial regions L4 and L5 is irradiated by the two upper light emitting elements 52U-4 and 52U-5 connected in series. For the upper partial region U6, the upper light emitting element 52U-6 is controlled to be turned on and off independently, as in the first embodiment. The upper partial areas U910 and U1113 are the same as the upper partial areas U45 and U13, respectively, and thus detailed description thereof is omitted.

  According to such a configuration, by maintaining the number of light emitting elements, each partial region can be irradiated with sufficient illuminance and light distribution area, while reducing the number of power sources of the light emitting elements and suppressing the product cost. Further, since the number of targets for turning on / off control is reduced, the processing load of the headlamp control unit 20 can be reduced.

  The number and area of the upper partial regions can be determined as appropriate according to the specifications of the light distribution control. In the example shown in FIG. 7B, the way of dividing the partial area is asymmetrical, but it may be symmetrical.

  The above embodiment is for facilitating understanding of the present invention, and does not limit the present invention. The present invention can be modified and improved without departing from the spirit of the present invention, and it is obvious that the present invention includes equivalents thereof.

  The number of partial regions included in the additional light distribution pattern PA is not limited to the above configuration. Two or more arbitrary numbers can be selected in the horizontal direction (HH line direction in FIG. 4). Further, only one row of partial regions may be arranged in the vertical direction (the VV line direction in FIG. 4).

  The shape of the partial region included in the additional light distribution pattern PA is not limited to the above configuration. At least one of the area and the shape of each partial region may be different from each other.

  A light source that irradiates a specific partial region does not need to be provided in each of the right headlight unit 22R and the left headlight unit 22L. As long as a desired additional light distribution pattern PA is obtained and a predetermined partial area can be irradiated, the position of at least one light source that irradiates each partial area in the vehicle 10 is arbitrary.

  The first lamp unit 36 for obtaining the low beam light distribution pattern PL may be configured by an LED array like the second right lamp unit 38R and the second left lamp unit 38L. In this case, the low beam light distribution pattern PL can be divided into a plurality of partial regions, and at least one of them can be selectively set as an irradiation region or a non-irradiation region.

  The headlamp control unit 20 may be configured to be provided for each of the right headlamp unit 22R and the left headlamp unit 22L.

  10: Vehicle, 11: Headlamp control system, 12: Headlamp device, 14: Integrated control unit, 20: Headlamp control unit, 22R: Right headlamp unit, 22L: Left headlamp unit, 52U: Upper side Light emitting element array, 52L: Lower light emitting element array, PA: Additional light distribution pattern, U1 to U13: Upper partial area, L1 to L13: Lower partial area

Claims (6)

A headlamp device mounted on a vehicle ,
Multiple light sources;
Control means for controlling irradiation of light by the plurality of light sources to form a predetermined irradiation region within an irradiation range including a plurality of partial regions,
The control means, the most illuminance high one of the plurality of partial regions in performing control for moving the scan smoldering Te the irradiation range in smell, of at least one of the plurality of partial areas that is part of the irradiation region A vehicle headlamp device that increases illuminance .   The control means performs the control so that the illuminance of the predetermined partial area in the irradiation area after the swivel movement is higher than the illuminance of the partial area corresponding to the predetermined partial area in the irradiation area before the swivel movement. The vehicle headlamp device according to claim 1, which is performed. The vehicle headlamp device according to claim 2, wherein the control means performs the control so that the illuminance of the entire irradiation region is substantially matched before and after the swivel movement.   4. The vehicle headlamp device according to claim 2, wherein the control unit performs the control so that the amount of increase in the illuminance increases as the partial area is closer to the driver's gaze estimation position. 5. Further comprising a storage unit for illuminance distribution irradiation morphism region after the movement is pre-stored a plurality of different irradiation patterns to each other,
It said control means selects one of said irradiation pattern in accordance with the traveling state of the vehicle, the vehicle headlamp apparatus according to any one of claims 1 to 4.   The vehicular headlamp device according to any one of claims 1 to 5, wherein the plurality of light sources are high beam light sources.

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