JPWO2016113818A1 - LIGHTING DEVICE, VEHICLE, AND LIGHTING DEVICE CONTROL METHOD - Google Patents

Abstract

Provided are a lighting device, a vehicle, and a control method that form a clear cut-off line with a simple configuration. The headlight includes a laser light source (11), a movable mirror (12), and a phosphor. The laser light source (11) generates laser light and irradiates the movable mirror (12). The movable mirror (12) rotates the mirror surface at a high speed under the control of the control unit. The movable mirror (12) reflects the laser beam generated from the laser light source (11) and irradiates the phosphor. The phosphor is irradiated with the laser beam reflected by the movable mirror (12) and excited to convert the laser beam into fluorescence. When there is another vehicle or person in front of the headlight, the control unit (24) reads the output pattern of the laser light source (11) corresponding to the position from the memory (22), and according to the read output pattern, Control the laser light source (11).

Description

  The present disclosure relates to a lighting device, a vehicle, and a method for controlling the lighting device.

  In recent years, laser light sources have attracted attention as light sources applied to automobile headlights because of their high efficiency and high directivity. When a laser light source is applied, it is possible to change the location (light distribution) illuminated by the headlights while traveling by using the high directivity, and by using a movable mirror. It is known that the light pattern can be controlled.

  Patent Document 1 is cited as a prior document related to the present disclosure. In Patent Document 1, a mirror that reflects light from a semiconductor light source is reciprocally rotated, and on / off (ON / OFF) of the semiconductor light source is controlled for each of a plurality of light control sections obtained by dividing the movement cycle of the mirror. A vehicular lamp that adjusts the illuminance distribution around the vehicle by combining ON / OFF control of a semiconductor light source with the periodic movement of the mirror is disclosed.

JP 2010-6109 A

  In general, when a laser light source is applied to an automobile headlight, a phosphor is excited by laser light emitted from the laser light source to obtain a white light source.

  However, in an automobile headlight using a laser light source and a phosphor, light is blurred unless a shade is used, and there is a problem that a cut-off line for preventing dazzling cannot be realized. Further, in this headlight, if a shade or a filter is used, a cut-off line for preventing dazzling can be realized, but there is a problem that the number of parts increases and the configuration becomes complicated.

  An object of the present disclosure is to provide a lighting device that forms a clear cut-off line with a simple configuration, a vehicle equipped with the lighting device, and a method for controlling the lighting device.

  An illumination device according to one embodiment of the present disclosure includes a laser light source, a movable mirror, a phosphor, a sensor, and a control unit. The laser light source generates laser light. The movable mirror has a mirror surface that reflects the laser beam and is movable. The phosphor includes a first region and a second region located outside the first region, and is disposed at a position where the laser beam reflected by the movable mirror is irradiated. Further, the phosphor converts laser light into fluorescence. The sensor detects an object that exists in the fluorescence irradiation direction. When the detected object is a person or a vehicle, the control unit avoids the irradiation of the laser beam to the first region, and the movable mirror so that the light intensity of the fluorescence emitted from the phosphor in the second region becomes non-uniform To control.

  A control method according to an aspect of the present disclosure includes a laser light source, a movable mirror, a phosphor, a sensor, and a control unit, and the phosphor is a first region and a first region located outside the first region. A lighting device control method comprising two regions, characterized by the following. That is, the laser light generated from the laser light source and reflected by the movable mirror irradiates the phosphor to generate fluorescence, the fluorescence irradiates the object, and the sensor detects the object. At that time, when the detected object is a person or a vehicle, the control unit avoids the irradiation of the laser beam to the first region, and the light intensity of the fluorescence emitted from the phosphor in the second region becomes non-uniform. Control the movable mirror or laser light source.

  According to the present disclosure, a clear cut-off line can be formed with a simple configuration.

Front view of a vehicle according to Embodiment 1 of the present disclosure Sectional view along the line II-II of the headlight on the left side of the vehicle in FIG. FIG. 3 is a block diagram illustrating a configuration for controlling the headlight according to the first embodiment of the present disclosure. The figure which shows an example of the output pattern of the laser light source memorize | stored in the memory of FIG. 3, and an example of the rotational speed pattern of a movable mirror The figure which shows the mode of the light intensity change of white light at the time of applying the output pattern of the laser light source shown in FIG. The flowchart which shows the control procedure in the control part of FIG. The figure which shows the optical simulation result of the headlight which concerns on Embodiment 1 of this indication. Flow chart showing a control procedure in the control unit according to the second embodiment of the present disclosure.

  Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings.

(Embodiment 1)
FIG. 1 is a front view of a vehicle according to the first embodiment of the present disclosure. Here, it is assumed that the vehicle is arranged horizontally on the road. Hereinafter, the surface on which the vehicle is disposed is referred to as a horizontal plane, and a direction perpendicular to the horizontal plane is referred to as a vertical direction. In FIG. 1, headlights 2 are arranged on the left and right sides of the front portion of the vehicle body 1. The headlight 2 is arranged with the light irradiation direction facing the outside of the vehicle.

  2 is a transverse sectional view (II-II sectional view) of the headlight 2 on the left side of the vehicle in FIG. Hereinafter, the configuration of the headlight 2 will be described with reference to FIG. However, the configuration of the headlight on the right side of the vehicle is bilaterally symmetric with the configuration of the headlight on the left side of the vehicle, and a detailed description thereof is omitted here. The headlight 2 includes a laser light source 11, a movable mirror 12, a phosphor 13, and a lens 14.

  The laser light source 11 generates laser light and irradiates the movable mirror 12. The laser light source 11 is a semiconductor laser element composed of, for example, a group III nitride semiconductor, and the laser light is, for example, blue (wavelength 430 nm to 470 nm).

  The movable mirror 12 is a MEMS (Micro Electro Mechanical System) mirror, for example, and rotates the mirror surface at high speed around one or two axes under the control of a control unit (not shown). The movable mirror 12 reflects the laser beam generated from the laser light source 11 and irradiates the phosphor 13. In the following description, it is assumed that the mirror surface rotates around one axis in the vertical direction.

The phosphor 13 is excited by being irradiated with the laser light reflected by the movable mirror 12, and converts the laser light into fluorescence. Here, the phosphor 13 converts blue laser light into white light and becomes a white light source. Examples of the phosphor material constituting the phosphor 13 include a YAG phosphor, a SiAlON phosphor, and a CaAlSiN ₃ phosphor. However, the phosphor 13 may convert the laser light into not only white light but also light yellow light, orange light, and the like.

  The phosphor 13 has a rectangular shape with the horizontal direction as the longitudinal direction, for example.

  The lens 14 diffuses white light emitted by the phosphor 13 and irradiates the front of the vehicle. The optical axis 15 of the lens 14 passes, for example, the center of the rectangle (that is, the center of the phosphor 13).

  FIG. 3 is a block diagram showing a configuration for controlling the headlight 2 according to the first embodiment of the present invention. The operation device 21 is a switch for switching the headlight 2 on / off.

  The memory 22 stores a plurality of output patterns of the laser light source 11 according to the position in front of the headlight, that is, the position where another vehicle or person such as an oncoming vehicle is present in the irradiation direction of white light.

  The sensor 23 detects whether there is another vehicle or a person in front of the headlight, and if there is another vehicle or person, detects the position thereof.

  The laser light source 11 switches the output of the laser light according to the control of the control unit 24.

  The movable mirror 12 switches the rotation speed of the mirror according to the control of the control unit 24.

  When the controller 21 switches the headlight 2 to ON, the control unit 24 receives an ON signal and acquires information on whether there is another vehicle or a person in front of the headlight from the sensor 23. If there is a vehicle or a person, the position information is also acquired. When there is another vehicle or person in front of the headlight, the control unit 24 reads the output pattern of the laser light source 11 corresponding to the position from the memory 22 and controls the laser light source 11 according to the read output pattern. .

  An example of the output pattern of the laser light source 11 stored in the memory 22 of FIG. 3 is shown in FIG. In FIG. 4, when the position of the center on the phosphor 13 (rectangular center for the above-described rectangular phosphor) is set to coordinate 0 and the laser light irradiation direction is oriented at coordinate 0, for example, fluorescence The right side on the body 13 is indicated by positive coordinates, and the left side on the phosphor 13 is indicated by negative coordinates. In FIG. 4, the output pattern value “0” indicates that the output of the laser light source 11 is 0, and the output pattern value “1” indicates that the output of the laser light source 11 is 100% (corrects the light intensity). The normal output in the case of not performing is 100%), and the numerical value “2” of the output pattern indicates that the output of the laser light source 11 is 200%.

  In the conventional output pattern in which the light intensity is not corrected, the first area of the coordinates −1 to 1 is set to the value “0”, and all other coordinates are set to the value “1”. On the other hand, in the output pattern for correcting the light intensity, the first area of the coordinates −1 to 1 is the numerical value “0”, the coordinate −2, 2 is the numerical value “0”, the coordinates −4, −3, 3, 4 Is a numerical value “2”, coordinates −5 and 5 are numerical values “0”, coordinates −6 and 6 are numerical values “2”, coordinates −7 and 7 are numerical values “0”, and coordinates −8 and 8 are numerical values “1”. Yes. The coordinates −7 to −2 and the coordinates 2 to 7 are the second area.

  In this way, when correcting the light intensity, the output of the laser light source 11 that irradiates the first region that is the region on the phosphor 13 corresponding to the irradiation direction to another vehicle or person is set to 0, and The output of the laser light source 11 is varied to irradiate the second region which is a predetermined region in the phosphor 13 outside the first region. Thereby, the light intensity of the white light at the boundary between the first region and the second region becomes abrupt, the spread due to the Lambertian distribution can be reduced, and a clear cut-off line can be formed. At this time, the total amount of white light does not change before and after correction. As a result, it is possible to prevent the system from being destroyed due to an excessive increase in the output of the laser light source 11.

  FIG. 5 shows a change in the light intensity of white light when the output pattern of the laser light source 11 shown in FIG. 4 is applied. In FIG. 5, the horizontal axis represents coordinates, and the vertical axis represents the light intensity [%] of white light. The dotted line shows the change in the light intensity of the white light when the light intensity is not corrected, and the solid line shows the change in the light intensity of the white light when the light intensity is corrected. The light intensity of 100% is, for example, the light intensity required by a rule set by a country or an organization.

  When the first region in which the white light emission is desired to be avoided is between coordinates −1 and 1, the light intensity is not 0 and the white light is emitted without the light intensity correction. . On the other hand, in the case of light intensity correction, the light intensity is almost 0 and no white light is emitted. In addition, it turns out that the light intensity of the white light emitted from the phosphor is nonuniform in the second region, which is a predetermined region outside the first region where it is desired to avoid the emission of white light, that is, there is unevenness.

  Next, the control procedure in the control unit 24 described above will be described with reference to FIG. The control unit 24 determines whether or not an ON signal indicating that the headlight 2 is ON is input from the operation device 21 (step S01).

  If it is determined in step S01 that an ON signal has been input (step S01: YES), the control unit 24 activates the laser light source 11 and the movable mirror 12 (step S02).

  Subsequently, the control unit 24 determines whether or not detection information indicating that another vehicle or a person has been detected in front of the headlight is input from the sensor 23 (step S03).

  When it is determined in step S03 that detection information has been input (step S03: YES), the control unit 24 reads the output pattern of the laser light source 11 with light intensity correction from the memory 22, and performs laser processing according to the read output pattern. The output of the light source 11 is controlled (step S04), and the flow returns to step S01.

  If it is determined in step S03 that no detection information has been input (step S03: NO), the flow returns to step S01.

  In step S01, when it is determined that the ON signal is not input (step S01: NO), the control unit 24 stops the laser light source 11 and the movable mirror 12 (step S05) and ends the control procedure.

  FIG. 7 is a diagram showing an optical simulation result of the headlight 2 according to the first embodiment of the present invention. 7A shows an optical simulation result without light intensity correction, and FIG. 7B shows an optical simulation result with light intensity correction. In FIG. 7A, blurring occurs in the cut-off area indicated by the dotted frame in the drawing. On the other hand, in FIG. 7B, it can be seen that the blur in the cut-off region indicated by the dotted frame in the figure is reduced.

  Thus, according to the first embodiment, when there is another vehicle or person in front of the headlight, the area on the phosphor 13 corresponding to the irradiation direction to the other vehicle or person is set as the first area, A predetermined area in the phosphor 13 outside the first area is defined as a second area. At this time, the first region is irradiated with the output of the laser light source 11 set to 0, and the output of the laser light source 11 is varied in the second region with an output pattern according to the position of another vehicle or person. The light intensity of the white light emitted from the phosphor 13 in the second region is made non-uniform. Accordingly, the cut-off line can be clearly formed with a simple configuration without adding a part such as a shade or a filter.

(Embodiment 2)
In the first embodiment, the case where the output of the laser light source is controlled has been described. In the second embodiment of the present disclosure, a case where the rotational speed of the movable mirror is controlled will be described.

  The configuration of the headlight according to the second embodiment of the present disclosure is the same as the configuration of FIGS. 2 and 3 of the first embodiment, and will be described with reference to these drawings as appropriate.

  Referring to FIG. 3, the memory 22 stores a plurality of rotational speed patterns of the movable mirror 12 according to the position where another vehicle or person is present in front of the headlight.

  When the controller 21 switches the headlight 2 to ON, the control unit 24 receives an ON signal and acquires information on whether there is another vehicle or a person in front of the headlight from the sensor 23. If there is a vehicle or a person, the position information is also acquired. When there is another vehicle or a person in front of the headlight, the control unit 24 reads the rotational speed pattern of the movable mirror 12 corresponding to the position from the memory 22 and moves the movable mirror 12 according to the read rotational speed pattern. Control.

  An example of the rotational speed pattern of the movable mirror 12 stored in the memory 22 is shown in FIG. In FIG. 4, the position on the phosphor 13 that emits laser light to irradiate white light to the position (center position) of another vehicle or person is set to coordinate 0, and the laser light irradiation direction is directed at coordinate 0. Sometimes, for example, the right side on the phosphor 13 is indicated by positive coordinates, and the left side on the phosphor 13 is indicated by negative coordinates. In the figure, the numerical value “0” of the rotational speed pattern represents that the rotational speed of the movable mirror 12 is, for example, 100% of the maximum speed and the output of the laser light source 11 is 0, and the numerical value “1” of the rotational speed pattern is The rotation speed of the movable mirror 12 is represented as 100% of the maximum speed, for example, and the numerical value “2” of the rotation speed pattern represents the rotation speed of the movable mirror 12 as 50% of the maximum speed. In the numerical values “1” and “2”, the output of the laser light source 11 is 100%.

  In this way, by setting the numerical value “0” to the numerical value “2” of the rotation speed pattern, the light intensity of the white light emitted from the phosphor 13 increases as the rotation speed of the movable mirror 12 decreases. If the light intensity of the white light in “1” is 1, the light intensity of the white light in the numerical value “2” is doubled. Note that with the numerical value “0”, the light intensity of white light is zero.

  In a conventional rotational speed pattern without light intensity correction, the first region of coordinates −1 to 1 is set to a numerical value “0”, and the other coordinates are set to a numerical value 1. On the other hand, in the rotational speed pattern to be corrected, the first area of the coordinates −1 to 1 is represented by a numerical value “0”, the coordinates −2 and 2 are represented by a numerical value “0”, and the coordinates −4, −3, 3 and 4 are represented. Numerical value “2”, coordinates −5 and 5 are numerical values “0”, coordinates −6 and 6 are numerical values “2”, coordinates −7 and 7 are numerical values “0”, and coordinates −8 and 8 are numerical values “1”. . The coordinates −7 to −2 and the coordinates 2 to 7 are the second area.

  In this way, when correcting the light intensity, the output of the laser light source 11 that irradiates the first region that is the region on the phosphor 13 corresponding to the irradiation direction to another vehicle or person is set to 0, and The rotational speed of the movable mirror 12 is varied to irradiate the second region, which is a predetermined region in the phosphor 13 outside the first region. Thereby, the light intensity of the white light at the boundary between the first region and the second region becomes abrupt, the spread due to the Lambertian distribution can be reduced, and a clear cut-off line can be formed. At this time, it is assumed that the total amount of white light does not change before and after correction.

  Next, the control procedure in the control unit 24 described above will be described with reference to FIG. However, in FIG. 8, the same reference numerals as those in FIG.

  If it is determined in step S03 that detection information has been input (step S03: YES), the control unit 24 reads the rotational speed pattern of the movable mirror 12 with correction from the memory 22, and moves according to the read rotational speed pattern. The rotational speed of the mirror 12 is controlled (step S11), and the flow returns to step S01.

  Thus, according to the second embodiment, when another vehicle or person is present in front of the headlight, the area on the phosphor 13 corresponding to the irradiation direction to the other vehicle or person is set as the first area. A predetermined region in the phosphor 13 outside the first region is set as the second region, and the first region is irradiated with the output of the laser light source 11 set to zero. At this time, in the second region, the rotational speed of the movable mirror 12 is varied with a rotational speed pattern according to the position of another vehicle or person, and the light intensity of the white light emitted from the phosphor 13 in the second region is not allowed. By making it uniform, a cut-off line can be clearly formed with a simple configuration without adding parts such as a shade or a filter.

  The embodiment according to the present disclosure has been described above.

  In each of the above-described embodiments, the vehicle headlight has been described as an example of the lighting device. However, the present disclosure is not limited thereto, and the lighting device includes a vehicle brake lamp, a tail lamp, a fog lamp, a turn signal lamp, and a position. Lights other than lamps and vehicles may be used.

  Further, in each of the above embodiments, when the movable mirror 12 is a MEMS mirror, the mirror surface has been described as rotating about one axis in the vertical direction. However, the present disclosure is not limited thereto, and the mirror surface is horizontal. It may be rotated around one axis in the direction, or may be rotated around two axes in the vertical direction and the horizontal direction.

  In the above embodiments, the movable mirror 12 has been described as a MEMS mirror. However, the present disclosure is not limited to this, and a mirror such as a DMD (Digital Mirror Device) may be used. When the movable mirror 12 is a DMD, an area to be irradiated by reflecting the laser light emitted from the laser light source 11 can be selected two-dimensionally under the control of the control unit 24.

  In each of the above embodiments, as an example of the laser light source 11, a semiconductor laser element composed of a group III nitride semiconductor emitting blue (wavelength: 430 nm to 470 nm) is used. However, the present invention is not limited thereto, and the wavelength is 400 nm to 430 nm. The semiconductor laser element emitting blue violet or purple may be used. Further, it may be a semiconductor laser element that emits ultraviolet light having a wavelength of 400 nm or less. When the laser light source 11 emits light having a wavelength of 430 nm or less, the phosphor 13 uses a phosphor that emits blue light, a phosphor that emits green light, and a phosphor that emits red light. Alternatively, green light and red light may be emitted and extracted from the headlight 2 as white light.

  Further, the invention according to the present disclosure may combine the first embodiment and the second embodiment. That is, both the output of the laser light source and the rotational speed of the movable mirror may be controlled simultaneously.

  The invention according to the present disclosure is useful for forming a clear cut-off line for preventing dazzling in a headlight with a simple configuration.

DESCRIPTION OF SYMBOLS 1 Main body body 2 Headlight 11 Laser light source 12 Movable mirror 13 Phosphor 14 Lens 15 Optical axis 21 Controller 22 Memory 23 Sensor 24 Control part

Claims (6)

A laser light source for generating laser light;
A movable mirror that reflects the laser beam and has a movable mirror surface;
A phosphor having a first region and a second region located outside the first region, the phosphor being disposed at a position where the laser beam reflected by the movable mirror is irradiated, and the laser beam A phosphor that converts the light into fluorescence;
A sensor for detecting an object present in the direction of fluorescence irradiation;
When the detected object is a person or a vehicle, the irradiation of the laser beam to the first region is avoided, and the light intensity of the fluorescence emitted from the phosphor in the second region is made non-uniform. A control unit for controlling the movable mirror or the laser light source;
A lighting device comprising: The control unit controls the output of the laser light source with an output pattern according to the position of the object to make the light intensity of the fluorescence emitted by the second region non-uniform,
The lighting device according to claim 1. The control unit controls the driving speed of the movable mirror with a driving speed pattern according to the position of the object, and makes the light intensity of the fluorescence emitted from the second region non-uniform.
The lighting device according to claim 1 or 2. The control unit makes the total light amount of the fluorescence constant in a case where the light intensity of the fluorescence emitted from the second region is nonuniform and a case where the light intensity is uniform.
The illumination device according to any one of claims 1 to 3. Comprising the lighting device according to any one of claims 1 to 4,
A vehicle in which the illuminating device is arranged with the irradiation direction of the fluorescence facing outward. A laser light source, a movable mirror, a phosphor, a sensor, and a controller;
The phosphor is a method for controlling an illumination device including a first region and a second region located outside the first region,
When the laser light generated from the laser light source and reflected by the movable mirror irradiates the phosphor to generate fluorescence, the fluorescence irradiates the object, and the sensor detects the object,
When the detected object is a person or a vehicle, the control unit avoids laser light irradiation to the first region, and the light intensity of the fluorescence emitted by the phosphor in the second region becomes non-uniform. The control method of the illuminating device, wherein the movable mirror is controlled as described above.