WO2012124607A1

WO2012124607A1 - Illumination device, headlamp, and vehicle

Info

Publication number: WO2012124607A1
Application number: PCT/JP2012/056003
Authority: WO
Inventors: 野村　勝; 竹史塩見; 片岡　耕太郎; 足立　浩一郎; 太田　佳似; 岩田　浩
Original assignee: シャープ株式会社
Priority date: 2011-03-15
Filing date: 2012-03-08
Publication date: 2012-09-20
Also published as: TW201243218A

Abstract

　An illumination device is provided with: a headlamp unit (101) that has a laser light source (1); a laser drive circuit (102) that drives the laser light source (1); and an acceleration sensor (3) that detects the acceleration of the headlamp unit (101). When the laser drive circuit (102) is driving the laser light source (1) and the detection value from the acceleration sensor (3) exceeds a first threshold value, the laser drive circuit (102) pulse drives the laser light source (1) for a fixed period of time.

Description

Lighting device, headlamp and vehicle

The present invention relates to an illuminating device and a headlamp that use a semiconductor laser element (LD) as a light source, and a vehicle equipped with the headlamp.

In recent years, research on illumination devices using an LD as a light source has become active. Since the laser light generated from the LD has high directivity, the LD is used as a light source for a headlight of a vehicle such as an automobile.

In addition, vehicles such as automobiles equipped with the above headlights are provided with measures for improving safety during running or accidents.

For example, in Patent Document 1, the lateral acceleration of a vehicle traveling on a road that curves in the left-right direction is detected, and the right and left auxiliary illumination lights are turned on in addition to the headlights, thereby making the visibility when turning the vehicle Techniques for improving and ensuring safety during vehicle traveling are disclosed.

Further, in Patent Document 2, the magnitude of impact at the time of a vehicle collision at the time of an accident is detected by an acceleration sensor, a headlight failure determination is performed based on the detected value, and a secondary caused by headlight breakage is detected. Techniques for avoiding accidents and ensuring safety in the event of an accident are disclosed.

By the way, since the laser beam generated from the LD has high directivity, there is a possibility of damaging the retina when entering the human eye. For this reason, it is necessary to devise so that the laser beam generated from the LD is not leaked outside the apparatus as much as possible.

In particular, when an LD is used as the light source of a vehicle headlight, a high-power laser beam is required. Therefore, it is extremely dangerous if the laser beam leaks outside the vehicle due to damage to the headlight due to an accident or the like.

Further, Patent Document 3 discloses a light emitting device that stops energization of a semiconductor laser when the outside air enters the inside of a sealing means that blocks the semiconductor laser element from the outside air.

Japanese Patent Publication “Japanese Patent Laid-Open No. 2003-341423 (published on December 03, 2003)” Japanese Patent Publication “JP 2002-274295 A (published on Sep. 25, 2002)” Japanese Patent Publication “Japanese Patent Laid-Open No. 2009-146938 (published on July 02, 2009)”

However, Patent Documents 1 to 3 disclose technologies for determining whether or not there is a possibility of an accident such as a vehicle collision, and performing control for improving the safety of the headlight when there is such a possibility. Not disclosed.

The purpose of the present invention is to foresee as much as possible the occurrence of an accident such as a vehicle collision, and to shift the semiconductor laser to pulse drive emission based on that, and to turn off the light completely in the event of an accident, thereby ensuring safety. It is an object to provide an improved lighting device and headlamp.

In order to solve the above-described problem, an illumination device according to an embodiment of the present invention includes a light emitting unit that uses a semiconductor laser element as a light source, a drive circuit that drives the light source, and an acceleration that detects acceleration of the light emitting unit. And a driving circuit that drives the light source for a certain period of time when a value detected by the acceleration sensor exceeds a first threshold value while the light source is being driven.

In the above configuration, when the detection value indicating the acceleration of the light emitting unit by the acceleration sensor exceeds the first threshold while driving the light source, a state in which some abnormal impact is applied to the light emitting unit. Is shown.

In this state, if the light source is pulse-driven for a certain period of time, a semiconductor laser can be used as long as the pulse drive is in the off period even when the light-emitting portion is further subjected to a strong impact and causes damage. Laser light is not irradiated from the element.

Usually, there is a slight time lag from the instruction to stop driving in the driving state of the semiconductor laser element until the irradiation of the laser beam from the semiconductor laser element is stopped.

However, as described above, if the semiconductor laser element is pulse-driven, when the driving stop instruction is given, if the pulse driving is in the off period and the irradiation of the laser beam from the semiconductor laser element has already been stopped, the above-mentioned Such a time lag does not occur.

In other words, if the possibility of an accident is predicted by acceleration, the laser diode element is switched to pulse drive, so that if the accident becomes a reality and the lighting device is damaged, the laser beam is already turned off. Therefore, the probability that the leakage of the laser beam can be prevented, that is, the safety is increased.

A headlamp according to an embodiment of the present invention includes a lighting device that includes a light emitting unit using a semiconductor laser element as a light source and a drive circuit that drives the light source, and a braking signal for the vehicle. A brake signal detection sensor for detecting, and the drive circuit drives the light source for a certain period of time when the detection value by the brake signal detection sensor exceeds a fifth threshold value while driving the light source. It is characterized by that.

Here, when the vehicle slips in the front-rear direction, it is difficult to detect the difference between normal running and slip with an acceleration sensor. Therefore, detection when the vehicle slips in the front-rear direction is performed using a braking signal.

In the above configuration, when the value detected by the braking signal detection sensor exceeds the fifth threshold value while the light source is being driven, the vehicle is about to stop suddenly.

In this state, if the light source is pulse-driven for a certain period of time, even if the vehicle collides with some object as a result of slipping and the light emitting part is damaged, the pulse drive is in the off period. If present, the laser beam is not irradiated from the semiconductor laser element.

In other words, even if the acceleration to change the operation of the vehicle cannot be detected like the slip of the vehicle, the braking operation itself of the vehicle is detected and the semiconductor laser element is shifted to the pulse driving operation. Even if a collision between the vehicle and an object occurs later, the probability of laser light leakage can be reduced.

Usually, in the driving state of the semiconductor laser element, there is a slight time lag from the stop driving instruction until the irradiation of the laser beam from the semiconductor laser element is stopped.

However, as described above, the time lag as described above does not occur if the pulse drive is in the off period and the irradiation of the laser beam from the semiconductor laser element is already stopped when the semiconductor laser element drive stop instruction is given.

An illuminating device according to an embodiment of the present invention includes an illuminating device that is provided in a vehicle and includes a light emitting unit that uses a semiconductor laser element as a light source and a drive circuit that drives the light source, and detects an acceleration of the illuminating device. An acceleration calculation unit that calculates an acceleration in a direction orthogonal to the traveling direction of the vehicle from a speed signal indicating the speed of the vehicle and a steering angle signal indicating the steering angle of the vehicle, The drive circuit causes the light source to pulse-drive for a certain period of time when an absolute value of a difference between the acceleration calculated by the acceleration calculation unit and the acceleration detected by the acceleration sensor exceeds a seventh threshold value. It is said.

Here, for example, assuming a frozen road surface, even if the vehicle slips back and forth, even if the steering wheel is turned suddenly, the vehicle will slip almost unchanged without changing its attitude, or conversely, the attitude change (Spin ), And there is little change in acceleration in the vehicle longitudinal direction. In this case, it is difficult to detect the difference between normal running and slip with an acceleration sensor. Therefore, when the vehicle slips in the front-rear direction, a signal indicating the steering angle of the vehicle (steering angle signal) is used to determine whether the vehicle posture is intended by the driver, Recognize whether accident avoidance is being attempted.

That is, acceleration in a direction orthogonal to the traveling direction of the vehicle is calculated from a speed signal indicating the speed of the vehicle and a steering angle signal indicating the steering angle of the vehicle, and the calculated acceleration is detected by an acceleration sensor. When the absolute value of the difference from the acceleration exceeds the seventh threshold, the steering wheel is suddenly turned off while the vehicle slips, and it is in an unexpected rotation (spin), or while going straight ahead Also shows the state of spinning the vehicle.

In this state, if the light source is pulse-driven for a certain period of time, even if the vehicle is further shocked and the light emitting part is damaged, the semiconductor device can be used if the pulse drive is in the off period. Laser light is not irradiated from the laser element.

As a result, if the braking signal is detected and the light source is pulse-driven, the laser beam may be turned off even if the light emitting unit is actually damaged. It can be made highly safe with minimal light leakage.

The present invention includes a light emitting unit that uses a semiconductor laser element as a light source, a drive circuit that drives the light source, and an acceleration sensor that detects acceleration of the light emitting unit, and the drive circuit drives the light source. In this state, when the detection value by the acceleration sensor exceeds the first threshold, the light source is pulse-driven for a certain period of time, thereby reducing the probability of leakage of laser light when the light emitting unit is actually damaged, There is an effect that it can be improved.

It is a schematic block diagram of a headlamp according to an embodiment of the present invention. It is a block diagram which shows an example of the laser drive circuit in the said headlamp. (A) is a circuit diagram which shows a simple example for lighting the semiconductor laser (LD) in the said headlamp, (b) is a perspective view which shows the external appearance of the said semiconductor laser. It is a block diagram which shows an example of the laser drive part (step-down type) in the said laser drive circuit. It is a block diagram which shows an example of the laser drive part (boost type | mold) in the said laser drive circuit. It is a block diagram which shows an example of the acceleration judgment part in the said laser drive part. It is a block diagram which shows another example of the acceleration judgment part in the said laser drive part. It is a block diagram which shows another example of the acceleration judgment part in the said laser drive part. FIG. 9 is a diagram showing a reference voltage equalization circuit in the block shown in FIG. 8. It is a block diagram which shows another example of the acceleration judgment part in the said laser drive part. It is a timing chart of the operation | movement in the laser drive part shown in FIG. It is a figure which shows the equivalent circuit of the reference voltage in the block shown in FIG. It is a block diagram which shows another example of the acceleration judgment part in the said laser drive part. It is a timing chart of the operation | movement in the laser drive part shown in FIG. It is a timing chart of the basic operation of the headlamp according to the present embodiment. It is a timing chart of other operation | movement of the headlamp concerning this Embodiment. It is a timing chart of other operation | movement of the headlamp concerning this Embodiment. It is a timing chart of other operation | movement of the headlamp concerning this Embodiment. It is a timing chart of other operation | movement of the headlamp concerning this Embodiment. It is a figure which shows schematic structure of the headlamp which concerns on Example 1 of this Embodiment, and the motor vehicle provided with this headlamp. It is a figure which shows schematic structure of the motor vehicle provided with the headlamp which concerns on Example 2 of this Embodiment and this headlamp. It is a figure which shows schematic structure of the motor vehicle provided with the headlamp which concerns on Example 3 of this Embodiment and this headlamp. It is a figure which shows schematic structure of the headlamp which concerns on Example 4 of this Embodiment, and the motor vehicle provided with this headlamp. It is a figure which shows schematic structure of the headlamp which concerns on Example 5 of this Embodiment, and the motor vehicle provided with this headlamp. It is a figure which shows schematic structure of the headlamp which concerns on Example 6 of this Embodiment, and the motor vehicle provided with this headlamp. It is a figure which shows schematic structure of the headlamp which concerns on Example 7 of this Embodiment, and the motor vehicle provided with this headlamp. It is a figure which shows schematic structure of the headlamp which concerns on Example 8 of this Embodiment, and the motor vehicle provided with this headlamp. It is a timing chart of operation | movement of the headlamp shown in FIG. It is a figure which shows schematic structure of the headlamp which concerns on Example 9 of this Embodiment, and the motor vehicle provided with this headlamp. It is a figure which shows schematic structure of the headlamp which concerns on Example 10 of this Embodiment, and the motor vehicle provided with this headlamp. It is a figure which shows schematic structure of the headlamp which concerns on Example 11 of this Embodiment, and the motor vehicle provided with this headlamp. It is a schematic block diagram of a headlamp according to another embodiment of the present invention. It is a block diagram which shows an example of the laser drive circuit in the said headlamp. It is a block diagram which shows an example of the laser drive part (step-down type) in the said drive circuit. It is a block diagram which shows an example of the laser drive part (boost type | mold) in the said drive circuit. It is a figure which shows schematic structure of the headlamp which concerns on Example 12 of this Embodiment, and the motor vehicle provided with this headlamp. It is a figure which shows schematic structure of the headlamp which concerns on Example 13 of this Embodiment, and the motor vehicle provided with this headlamp. It is a figure which shows schematic structure of the headlamp which concerns on Example 14 of this Embodiment, and the motor vehicle provided with this headlamp. It is a figure which shows schematic structure of the headlamp which concerns on Example 15 of this Embodiment, and the motor vehicle provided with this headlamp. It is a block diagram which shows an example of the laser drive circuit in the said headlamp. It is a figure which shows schematic structure regarding the detection of vehicle speed information of the headlamp which concerns on Example 16 of further another embodiment of this invention, and the motor vehicle provided with this headlamp. It is a figure which shows schematic structure of the headlamp which concerns on Example 17 of this Embodiment, and the motor vehicle provided with this headlamp. It is a block diagram which shows an example of the laser drive circuit in the said headlamp. It is a figure for demonstrating the specific example of the generator of each steering signal and a braking signal.

In a prior application (Japanese Patent Application No. 2009-237076) filed by the applicant of the present application (Japanese Patent Laid-Open Publication No. 2011-0864432 (published on April 28, 2011)), when a vehicle collides A technique is disclosed in which a collision detection unit detects a collision and turns off the laser headlight. This prevents the laser light from leaking out of the vehicle due to damage to the headlight due to an accident or the like.

However, when the vehicle collides, the technology that detects the collision at the collision detection unit and turns off the laser headlights enters the extinguishing operation only after the collision is detected. Even for a short time until the detection unit (sensor) responds, it takes time until the power supply to the semiconductor laser is cut off, and there is a possibility that laser light leaks first. That is, a time lag occurs between the occurrence of a vehicle collision and the energization of the semiconductor laser is cut off, and thus there arises a problem that the laser beam leaks for a short time lag.

The purpose of the headlamp according to one embodiment of the present invention is to predict the occurrence of an accident such as a vehicle collision as much as possible, and to shift the semiconductor laser to pulse drive light emission based on that, and in the event of an accident It is to improve safety by turning it off completely.

In the headlamp according to the embodiment of the present invention, the laser is generated even in a short time by minimizing the time lag that occurs between the occurrence of a vehicle collision and the time when the semiconductor laser is de-energized. The possibility that light leaks can be reduced.

[Embodiment 1]
(Lighting device 100)
An embodiment of the present invention will be described as follows. Illumination device 100 according to the present embodiment is used as a headlamp mounted on a vehicle such as an automobile.

FIG. 1 is a schematic block diagram of a lighting device 100 according to the present embodiment.

As shown in FIG. 1, the illumination device 100 includes a headlamp unit (light emitting unit) 101 having a semiconductor laser element (LD) as a light source, and a laser drive for driving the LD of the headlamp unit 101. Circuit (driving circuit) 102.

The headlamp unit 101 includes a laser light source 1 composed of an LD, a light conversion unit 2 that converts laser light emitted from the laser light source 1 into visible light, and an acceleration sensor 3 that detects acceleration of the headlamp unit 101. Including.

The signal detected by the acceleration sensor 3 is transmitted to the laser drive circuit 102 as an acceleration signal S5.

The laser drive circuit 102 generates a laser drive current C0 corresponding to a laser control signal S0 from an illumination control unit (described later) and supplies the laser drive current C0 to the laser light source 1 of the headlamp unit 101.

The laser drive circuit 102 performs supply control of the laser drive current C0 to the laser light source 1 according to the value of the acceleration signal from the acceleration sensor 3.

That is, when the laser drive circuit 102 is driving the laser light source 1 (the headlamp is turned on), the value of the acceleration signal (detected value) by the acceleration sensor 3 exceeds the first threshold value. In this case, the laser light source 1 is pulse-driven for a certain time.

That is, when the value of the acceleration signal from the acceleration sensor 3 exceeds the first threshold, the laser driving circuit 102 causes the laser light source 1 to perform pulse driving for preparation for turning off.

Further, the laser drive circuit 102 sets a second threshold value in which the value (detection value) of the acceleration signal from the acceleration sensor 3 is larger than the first threshold value in a state where the laser light source 1 is pulse-driven. When it exceeds, the driving of the laser light source 1 is stopped (turned off).

The first threshold value is a value corresponding to the acceleration when the vehicle is suddenly braked or a value corresponding to the acceleration when the vehicle is suddenly turned off.

The second threshold is a value corresponding to the acceleration generated when the vehicle collides with another vehicle or the like.

Details of the turn-off control of the laser light source 1 in the laser drive circuit 102 will be described later.

(Laser drive circuit 102)
FIG. 2 is a schematic block diagram of the laser drive circuit 102.

The laser drive circuit 102 includes a laser control unit 121, a laser drive unit 122, and an output switch element 123, as shown in FIG.

The laser control unit 121 receives the signal S0 from the illumination control unit 103 installed outside, and returns a signal S4 to the illumination control unit 103. The signal S0 is a command signal for instructing turning on (ON) and turning off (OFF) of the laser light source 1, and a command signal for instructing the magnitudes of the driving voltage and driving current of the laser light source 1. The signal S4 is a status report signal including a lighting status of the laser light source 1 and an abnormality such as a failure.

Then, the laser control unit 121 transmits a signal S1 to the subsequent laser drive unit 122.

The laser driver 122 receives the signal S1 from the laser controller 121 and returns a signal S3 to the laser controller 121.

The signal S1 is a control signal that controls turning on (ON) and turning off (OFF) of the laser light source 1, and a control signal that indicates the magnitudes of the drive voltage and drive current. The signal S3 is a status report signal for reporting the status of the laser driving unit 122, reporting the driving current of the laser light source 1, and the driving voltage of the laser light source 1.

The laser driving unit 122 receives the signal S1 from the laser control unit 121, and supplies power from the power source E (battery) to the laser light source 1 as a driving voltage and a driving current C0.

The laser light source 1 is lit by the drive voltage and the drive current C0 supplied from the laser drive unit 122.

The acceleration signal S5 from the acceleration sensor 3 is supplied to the laser control unit 121 and the laser driving unit 122. The acceleration signal S5 from the acceleration sensor 3 is given to at least one of the laser controller 121 and the laser driver 122, and is a signal for transmitting information on acceleration (impact etc.). Based on this information (acceleration magnitude), the laser control unit 121 or the laser driving unit 122 controls the laser light source 1 to be turned off.

Here, in order to perform the extinction control of the laser light source 1 based on the magnitude of the acceleration signal S5 (the magnitude of the acceleration indicated by the acceleration signal S5), laser pulse driving (ON / OFF) is performed as preparation for extinction.

When the acceleration signal S5 is greater than a certain threshold (for example, a magnitude corresponding to an impact corresponding to a vehicle collision), the laser light source 1 can be irradiated with the laser light as quickly as possible. In order to stop (turn off the light), it is preferable to directly determine the magnitude of the acceleration signal S5 by the laser driving unit 122.

In the laser drive unit 122 described later, an example is shown in which the magnitude of the acceleration signal S5 is directly determined to control the extinction.

Whether or not the output switch element 123 is provided is arbitrary, but since the laser driving unit 122 includes a capacitor in many cases as will be described later, the acceleration sensor 3 detects a collision acceleration or a laser. It is desirable to provide for shortening the turn-off time of the laser light source 1 when an abnormality of the drive unit 122 is detected. Note that the output switch element 123 is controlled by at least one of the laser controller 121 and the laser driver 122. The signal S2 is a control signal for controlling ON and OFF of the output switch element 123.

The output switch element 123 is composed of, for example, a field effector (FET).

The laser light source 1 includes a plurality of LD chips 11, and laser light is irradiated from each of the LD chips 11.

(About LD chip 11)
A specific structure of the LD chip 11 will be described.

FIG. 3A is an example of a simple circuit diagram for lighting the LD chip 11, and FIG. 3B is a perspective view showing the appearance of the LD chip 11.

As shown in the figure, the LD chip 11 has a structure in which a cathode electrode 19, a substrate 18, a clad layer 113, an active layer 111, a clad layer 112, and an anode electrode 17 are laminated in this order.

The substrate 18 is a semiconductor substrate, and it is preferable to use GaN, sapphire, or SiC in order to obtain blue to ultraviolet excitation light for exciting the phosphor as in the present application. In general, as a substrate for a semiconductor laser, in addition, a group IV semiconductor such as Si, Ge, and SiC, GaAs, GaP, InP, AlAs, GaN, InN, InSb, GaSb, and AlN are represented by III. -V group compound semiconductor, ZnTe, ZeSe, II-VI group compound such as ZnS and ZnO _{_{_{semiconductor, ZnO, Al 2 O 3,}}} SiO 2, TiO 2, CrO 2 and CeO ₂ or the like oxide insulator, and, SiN Any material of a nitride insulator such as is used.

The anode electrode 17 is for injecting current into the active layer 111 through the clad layer 112.

The cathode electrode 19 is for injecting current into the active layer 111 from the lower part of the substrate 18 through the clad layer 113. The current is injected by applying a forward bias to the anode electrode 17 and the cathode electrode 19.

The active layer 111 has a structure sandwiched between the cladding layer 113 and the cladding layer 112.

In addition, as a material for the active layer 111 and the cladding layer, a mixed crystal semiconductor made of AlInGaN is used to obtain blue to ultraviolet excitation light. Generally, a mixed crystal semiconductor mainly composed of Al, Ga, In, As, P, N, and Sb is used as an active layer / cladding layer of a semiconductor laser, and such a configuration may be used. Further, it may be composed of a II-VI compound semiconductor such as Zn, Mg, S, Se, Te and ZnO.

The active layer 111 is a region where light emission occurs due to the injected current, and the emitted light is confined in the active layer 111 due to a difference in refractive index between the cladding layer 112 and the cladding layer 113.

Further, the active layer 111 is formed with a front side cleaved surface 114 and a back side cleaved surface 115 provided to face each other in order to confine light amplified by stimulated emission. The front side cleaved surface 114 and the back side cleaved surface 115 are formed. Plays the role of a mirror.

However, unlike a mirror that completely reflects light, a part of the light amplified by stimulated emission is obtained by cleaving the front side cleaved surface 114 and the back side cleaved surface 115 of the active layer 111 (in this embodiment, the front side cleaved surface 114 for convenience. And the laser beam L0. Note that the active layer 111 may form a multilayer quantum well structure.

A reflective film (not shown) for laser oscillation is formed on the back side cleaved surface 115 opposite to the front side cleaved surface 114, and the difference in reflectance between the front side cleaved surface 114 and the back side cleaved surface 115 is different. By providing, for example, most of the laser beam L0 can be irradiated from the light emitting point 116 from the front-side cleavage surface 114 which is a low reflectance end face.

As for film formation with each semiconductor layer such as the clad layer 113, the clad layer 112, and the active layer 111, MOCVD (metal organic chemical vapor deposition) method, MBE (molecular beam epitaxy) method, CVD (chemical vapor deposition) method. The film can be formed using a general film forming method such as a laser ablation method or a sputtering method. The film formation of each metal layer can be configured using a general film forming method such as a vacuum deposition method, a plating method, a laser ablation method, or a sputtering method.

In the laser light source 1, the plurality of LD chips 11 can be connected in various patterns in series and parallel. The laser driver 122 is configured according to the connection form of the plurality of LD chips 11 in the laser light source 1.

(Laser driver 122)
Next, details of the laser driving unit 122 will be described below with reference to FIGS. 4 and 5. 4 and 5 can be applied to the laser drive circuit 102 shown in FIG.

(Laser driver 122: step-down type)
FIG. 4 is a block diagram illustrating a circuit configuration of the step-down laser driving unit 122.

That is, FIG. 4 shows an example of a step-down circuit used when the voltage Vf necessary for driving the laser light source 1 is lower than the voltage Vb of the power source E (when the number of series of LD chips 11 is small). Yes.

As shown in FIG. 4, the step-down laser driver 122 includes a main switch element 1220, a coil 1221, a diode 1222, a capacitor 1223, a current detection resistor 1224, a differential amplifier 1225, a switching control unit 130, and an acceleration determination unit. 140 and the output switch element 123 described above. One end of the coil 1221 is connected to the power source E through the main switch element 1220. Note that another switch element may be provided between the power source E and the coil 1221.

The laser driving unit 122 is connected to the laser light source 1 including the single LD chip 11.

The switching control unit 130 receives the signal S1 from the laser control unit 121 and returns a signal S3 to the laser control unit 121. The signal S1 and the signal S3 are as described above. In addition, the switching control unit 130 receives the signal S1 and switches the main switch element 1220 between conduction (ON) and non-conduction (OFF) so that a (desired) current instructed to the laser light source 1 flows. Main switch control signal S8 is transmitted.

During the period when the main switch element 1220 is ON (ON period), the current from the power source E is accumulated as magnetic flux energy through the coil 1221 and as a charge in the capacitor 1223, and the current is also supplied to the laser light source 1. The current supplied to the laser light source 1 is detected by the current detection resistor 1224 and the differential amplifier 1225, and the main switch element 1220 is turned on / off so as to maintain the drive current value instructed from the laser controller 121.

4, the signal S6 is an output current signal, the signal S7 is an output voltage signal, and the signal S8 is a control signal that controls switching of the main switch element 1220 between ON and OFF.

In the OFF period (OFF period) of the main switch element 1220, the magnetic flux energy of the coil 1221 is supplied to the laser light source 1 together with the capacitor 1223 through the diode 1222. The capacitor 1223 performs a smoothing operation that relaxes fluctuations in voltage (current) to the laser light source 1 by switching the main switch element 1220 between ON and OFF.

The signal S7 (output voltage signal) is used for monitoring whether or not a voltage according to an instruction from the laser control unit 121 is output. Further, when an abnormally high voltage is observed, the signal S7 assumes that the laser light source 1 is open or that the laser drive unit 122 has failed, and the main switch element 1220 is turned OFF to lower the output voltage (OFF Used).

The switching control unit 130 receives the signal S9 from the acceleration determination unit 140. The signal S9 is a signal for controlling the output timing of the signal S8 output from the switching control unit 130.

The acceleration determination unit 140 receives the acceleration signal S5 from the acceleration sensor 3, generates a signal S9 (also a signal S11 described later) based on the acceleration signal S5, and transmits the signal S9 to the switching control unit 130. ing. Details of the acceleration determination unit 140 will be described later.

Further, the output switch element 123 is turned on when the semiconductor laser is turned on, but is turned off when pulse driving for preparation for turning off is performed at a high speed and when an acceleration corresponding to a collision is detected. This ON / OFF control is performed by at least one of the laser controller 121 and the laser driver 122. In order to extinguish as quickly as possible when an acceleration corresponding to a collision is detected, the acceleration determination unit 140 is replaced with the laser control unit 121 and the laser drive unit 122 is observed, and the laser drive unit 122 directly outputs the output switch element 123. It is desirable to turn off. Needless to say, the laser control unit 121 may be provided with the acceleration determination unit 140.

Since the laser drive unit 122 includes the coil 1221 and the capacitor 1223 for storing energy as described above, even if the switching control unit 130 turns off the main switch element 1220, the current to the laser light source 1 is not turned off immediately. . Therefore, it is more desirable to provide a means for forcibly (at a high speed) interrupting current like the output switch element 123.

(Laser driver 122: boost type)
FIG. 5 is a block diagram illustrating a circuit configuration of the boost type laser driving unit 122.

That is, FIG. 5 shows a case where the voltage Vf necessary for driving the laser light source 1 is higher than the voltage Vb of the power source E (a plurality of LD chips 11 are slightly in series (the number of series is 3 to 4 or more). ) Shows an example of a step-up circuit used for connection).

As shown in FIG. 5, the boost type laser driver 122 includes a main switch element 1220, a coil 1221, a diode 1222, a capacitor 1223, a current detection resistor 1224, a differential amplifier 1225, a switching control unit 130, and an acceleration determination unit. 140 and the output switch element 123 described above. One end of the coil 1221 is connected to the power source E. Note that another switch element may be provided between the power source E and the coil 1221.

The laser driving unit 122 is connected to the laser light source 1 including a total of four LD chips 11.

The switching control unit 130 receives the signal S1 from the laser control unit 121 and returns a signal S3 to the laser control unit 121. The signal S1 and the signal S3 are as described above. In addition, the switching control unit 130 receives the signal S1 and switches the main switch element 1220 between conduction (ON) and non-conduction (OFF) so that a (desired) current instructed to the laser light source 1 flows. .

During the period when the main switch element 1220 is ON, the current from the power source E is accumulated as magnetic flux energy through the coil 1221 and as a charge in the capacitor 1223. During this period, current is supplied to the laser light source 1 from the capacitor 1223.

On the other hand, when the main switch element 1220 is OFF, the magnetic flux energy of the coil 1221 becomes a current, and the capacitor 1223 is charged via the diode 1222 in series with the voltage of the power source E, and the current is also supplied to the laser light source 1. The

The current supplied to the laser light source 1 is detected by the current detection resistor 1224 and the differential amplifier 1225, and the main switch element 1220 is turned on / off so as to maintain the drive current value instructed from the laser controller 121.

Note that the signal S6 shown in FIG. 5 is an output current signal, the signal S7 is an output voltage signal, and the signal S8 is a control signal for controlling switching of the main switch element 1220 between ON and OFF.

In the above configuration, since the coil 1221 and the capacitor 1223 for storing energy exist, even if the switching control unit 130 turns off the main switch element 1220, the energization to the laser light source 1 is not turned off immediately. Therefore, the output switch element 123 may be configured to forcibly cut off the current (at high speed).

Since the laser drive unit 122 includes the coil 1221 and the capacitor 1223 for storing energy as described above, even if the switching control unit 130 turns off the main switch element 1220, the current to the laser light source 1 is not turned off immediately. . Therefore, it is desirable to provide a means for forcibly (at high speed) cutting off the current like the output switch element 123.

(Acceleration judgment unit 140)
Next, the acceleration determination unit 140 will be described below with reference to FIGS.

(1) Only single polarity and collision acceleration are judged and detected as digital signals FIGS. 6 and 7 are diagrams showing an example of the acceleration judgment unit 140 that judges and detects only single polarity and collision acceleration as digital signals.

FIG. 6 is a diagram illustrating a basic configuration example of the acceleration determination unit 140.

That is, as shown in FIG. 6, the acceleration determination unit 140 has a configuration including a reference voltage Vref to be compared with the acceleration signal S5 and a comparator (comparator) 1403 that compares the magnitudes.

In the acceleration determination unit 140, when the acceleration signal S5 exceeds the reference voltage Vref, the output of the comparator 1403 becomes a high level. That is, in this case, the signal S9 output from the comparator 1403 is a signal indicating that the acceleration when the vehicle collides is detected.

Note that the acceleration signal S5 of the acceleration sensor 3 is also used for detection of the extinction preparation acceleration, but the extinction preparation acceleration is smaller than the collision acceleration, and thus is not detected by the comparator 1403. For this reason, in order to detect the extinction preparation acceleration, the above-described switching control unit 130 has a microcomputer, and an analog / digital converter (A / D converter) is used to determine the acceleration of the sudden brake / quick handle as a digital value. This is done by the microcomputer software. In this case, the acceleration signal S5 of the acceleration sensor 3 is input to the switching control unit 130. Of course, the output signal S9 of the comparator 1403 may also be supplied to the switching control unit 130 and used as a start signal for pulse driving, which is a light-off preparation operation.

The above-described extinction preparation acceleration is an acceleration for determining whether or not to perform pulse driving such that the laser light source 1 is not extinguished completely but is repeatedly extinguished and lit.

The collision acceleration is an acceleration for determining whether or not a vehicle equipped with the lighting device 100 has collided.

Therefore, the reference value for determining the extinction preparation acceleration is set to a value lower than the reference value for determining the collision acceleration.

In the acceleration determination unit 140, when the amplitude of the acceleration signal S5 from the acceleration sensor 3 is weak, the amplifier 1401 as shown by the broken line in FIG. 6 is placed before the comparator 1403 or the amplifier 1402 is placed in the comparator 1403. It may be provided on either or both of the A / D conversion target signal lines branched from the input.

Further, if the processing speed of the microcomputer mounted on the switching control unit 130 is sufficiently high and the A / D conversion function (signal line, conversion speed) is sufficient, the comparator 1403 and the reference voltage Vref are eliminated, and the collision acceleration This determination may also be made by software.

Also, the reference voltage Vref is not necessarily an individual / fixed voltage source.

FIG. 7 shows an acceleration determination unit 140 provided with a resistor 1404 and a capacitor 1405 instead of the reference voltage Vref of the acceleration determination unit 140 shown in FIG.

When the laser controller 121 and the laser driver 122 include a microcomputer, or when a PWM (pulse width modulation) output or digital / analog conversion (D / A conversion) output of a microcomputer such as the illumination controller 103 can be used, The output value can be set to either a fixed value or a variable value by operating the microcomputer. At the time of PWM output, it is output as a pulse of High and Low, so that it is converted to a direct current smoothed by a resistor 1404 and a capacitor 1405 to perform the same function as the reference voltage Vref.

Note that the resistor 1404 and the capacitor 1405 are not necessarily required for D / A conversion output.

Further, although the acceleration determination unit 140 having the above-described configuration is configured to detect only the collision acceleration, it may be configured to detect only the extinguishing preparation acceleration with the same configuration. That is, the value of the reference Vref may be lowered so that the laser light source 1 is driven to be pulsed so that it is not extinguished but is extinguished.

(2) Judgment / detection of single polarity, collision acceleration and extinction preparation acceleration as digital signals FIGS. 8 and 9 are diagrams of acceleration judgment unit 140 that judges / detects single polarity, collision acceleration and extinction preparation acceleration as digital signals. It is a figure which shows an example.

Here, an example in which the acceleration determination unit 140 detects the extinction preparation acceleration that has not been detected by the acceleration determination unit 140 shown in FIGS. 6 and 7 will be described.

The acceleration determination unit 140 shown in FIG. 8 is configured by arranging two acceleration determination units 140 shown in FIG.

That is, as shown in FIG. 8, the acceleration determination unit 140 uses (I) Vref1 corresponding to the extinction preparation acceleration as a reference voltage to be compared with the acceleration signal S5, and (II) Vref2 corresponding to the collision acceleration. And

comparators

1403 and 1406 for comparing each of them with the acceleration signal S5 of the acceleration sensor 3.

That is, in the acceleration determination unit 140, if the received acceleration signal S5 exceeds Vref1, a signal S11 indicating that the extinction preparation acceleration is detected is output from the comparator 1403, and the received acceleration signal S5 exceeds Vref2. If so, the comparator 1406 outputs a signal S9 indicating that the collision acceleration has been detected.

Here, in the acceleration determination unit 140, when the amplitude of the acceleration signal S5 from the acceleration sensor 3 is weak, the amplifier 1401 as shown by the broken line in FIG. 8 is placed in front of the comparator 1403, or the amplifier 1402 is placed in the comparator 1406. It may be provided before or both.

Further, the relationship between the reference voltages Vref1 and Vref2 to be compared is such that Vref1 <Vref2 when the amplification degree from the acceleration signal S5 to the comparator 1403 and the comparator 1406 is the same, or when the amplifier 1401.1402 is not provided. There is a relationship.

On the other hand, when the amplification levels from the acceleration signal S5 to the comparator 1403 and the comparator 1406 are not the same, or when the

amplifiers

1401 and 1402 are provided, (I) the comparator 1403 indicates a detection output when the extinction preparation acceleration is detected. When the signal S11 is output and (II) the collision acceleration is detected, the reference voltages Vref1 and Vref2 may be set so that the comparator 1406 also outputs the signal S9 indicating the detection output.

Further, the reference voltages Vref1, 2 need not necessarily be individual / fixed voltage sources.

FIG. 9 is a diagram showing an alternative configuration of the reference voltages Vref1 and Vref2 of the acceleration determination unit 140 shown in FIG.

When the laser controller 121 and the laser driver 122 include a microcomputer, or when a PWM (pulse width modulation) output or digital / analog conversion (D / A conversion) output of a microcomputer such as the illumination controller 103 can be used, The output value can be set to either a fixed value or a variable value by operating the microcomputer. During PWM output, it is output as High and Low pulses, so as shown in FIG. 9, it is converted to a direct current smoothed by a resistor 1404 and a capacitor 1405, and performs the same function as the reference voltages Vref1 and Vref2. Make it.

(3) Judgment and detection of only positive and negative polarities and collision acceleration as digital signals with reference to a certain voltage FIGS. 10 to 12 show accelerations for judging and detecting only positive and negative polarities and collision acceleration as digital signals with reference to a certain voltage. It is a figure which shows the example of the judgment part.

The acceleration determination unit 140 illustrated in FIG. 10 has a configuration similar to that of the acceleration determination unit 140 illustrated in FIG. 8, but corresponds to (I) plus-side collision acceleration as a reference voltage to be compared with the acceleration signal S5. + Vref, (II) −Vref corresponding to the negative side collision acceleration, and

comparators

1403 and 1406 for comparing each with the acceleration signal S5 of the acceleration sensor 3.

The

comparators

1403 and 1406 are called open collectors or open drains. When the output is (I) high level, the output is equivalently OFF, and when the output is (II) low level, the current is sucked. Yes.

For this reason, even if the

comparators

1403 and 1406 are directly connected, even if one of them outputs a high level and the other outputs a low level, there is no possibility that a large current flows and is damaged due to the output collision between the two.

In the acceleration determination unit 140, the level of the acceleration signal S5 from the acceleration sensor 3 is given to the

comparators

1403 and 1406, with + Vref being the level for which the + side determination is desired and −Vref being the level for the −side determination. The outputs of the

comparators

1403 and 1406 are connected to a voltage “+ Vcc” to be equivalent to a high level output through a resistor 1407.

The relationship between the

comparators

1403 and 1406 in the acceleration determination unit 140 having the above-described configuration is called a “window comparator”. As shown in FIG. 11, the acceleration signal from the acceleration sensor 3 is “+ Vref and −Vref”. When it deviates from the “window”, a detection output (in this case, Low level) is emitted. The timing chart shown in FIG. 11 shows a case where the amplifier AMP is not provided in the acceleration determination unit 140 shown in FIG.

Acceleration signal Vnorm for zero acceleration need not be zero volts. It is sufficient that + Vref is larger than Vnorm on the + side and −Vref is larger than Vnorm on the − side. Further, the absolute value of the difference between Vnorm and + Vref and the absolute value of the difference between Vnorm and -Vref do not have to be the same.

In the acceleration determination unit 140 shown in FIG. 10, when the amplitude (sensor sensitivity) of the acceleration signal is small,

amplifiers

1401 and 1402 may be provided as appropriate.

Further, in the acceleration determination unit 140, the acceleration at the light extinction preparation stage is A / D converted by the switching control unit 130 and observed by the microcomputer in the same manner as the acceleration determination unit 140 shown in FIG.

FIG. 12 is a diagram showing a configuration instead of the reference voltages + Vref and −Vref of the acceleration determination unit 140 shown in FIG.

When the laser controller 121 and the laser driver 122 include a microcomputer, or when a PWM (pulse width modulation) output or digital / analog conversion (D / A conversion) output of a microcomputer such as the illumination controller 103 can be used, The output value can be set to either a fixed value or a variable value by operating the microcomputer. Since the PWM output is a High and Low pulse, it is converted to a direct current smoothed by a resistor 1404 and a capacitor 1405 as shown in FIG. 12, and functions equivalent to the reference voltages + Vref1 and -Vref. Let it be done.

(4) Positive / negative polarity, collision acceleration, and extinction preparation acceleration are determined and detected as digital signals with reference to a certain voltage. FIGS. 13 and 14 are digital signals with positive / negative polarity, collision acceleration, and extinction preparation acceleration as a reference with a certain voltage. It is a figure which shows the example of the acceleration judgment part 140 judged and detected as.

The acceleration determination unit 140 illustrated in FIG. 13 has a configuration similar to that of the acceleration determination unit 140 illustrated in FIG. 10, but corresponds to (I) a plus-side extinction preparation acceleration as a reference voltage to be compared with the acceleration signal. + Vref1, (II) corresponding to the minus-side extinction preparation acceleration, −Vref1, (III) corresponding to the plus-side collision acceleration, + Vref2, (IV) corresponding to the minus-side collision acceleration, −Vref2, and Each of the

comparators

1403, 1406, 1408, and 1409 is compared with the acceleration signal S 5 of the acceleration sensor 3.

The

comparators

1403, 1406, 1408, and 1409 are called open collectors or open drains. (I) When the output is high level, the output is equivalently OFF, and when the output is (II) low level, current is sucked. It is like that.

For this reason, even if the

comparators

Similarly, even if the

comparators

1408 and 1409 are directly connected, even if one of them outputs a high level and the other outputs a low level, there is no possibility that a large current flows and damages due to the output collision between the two.

In the acceleration determination unit 140, the level of the acceleration signal S5 from the acceleration sensor 3 is set to + Vref1 and 2, and the level of the acceleration signal S5 to be determined to −Vref1 and 2, and is set to −Vref1 and 2, respectively. Give each. Then, the outputs of the

comparators

1403 and 1406 are connected and connected to a voltage “+ Vcc” to be equivalent to a high level output through the resistor 1410. Further, the outputs of the

comparators

1408 and 1409 are connected and connected to a voltage “+ Vcc” to be equivalent to a High level output through a resistor 1411.

The relationship between the

comparators

1403 and 1406 and the relationship between the

comparators

1408 and 1409 in the acceleration determination unit 140 having the above configuration is called a “window comparator”. As shown in FIG. 14, the acceleration signal from the acceleration sensor 3 is + Vref1, A detection output (in this case, a Low level) is generated when the signal falls outside the “window” between 2 and −Vref 1 and 2. The timing chart shown in FIG. 14 shows a case where the amplifier AMP is not provided in the acceleration determination unit 140 shown in FIG.

Acceleration signal Vnorm for zero acceleration need not be zero volts. It is only necessary that + Vref1 and 2 are larger on the + side than Vnorm and −Vref1 and 2 are larger on the −side than Vnorm. Further, the absolute value of the difference between Vnorm and + Vref1, 2 and the absolute value of the difference between Vnorm and -Vref1, 2 do not have to be the same. However, each level needs to be set to a relationship as shown in the lower level of the upper and lower levels indicating the relationship between High and Low in the timing chart shown in FIG.

(Operation of lighting apparatus 100)
Next, the operation of the illumination device 100 having the above configuration will be described below with reference to timing charts shown in FIGS.

(A) in FIG. 15 to FIG. 19 show graphs in which the absolute value of the acceleration generated in the vehicle is recorded over time. In this graph, two threshold values are set here. That is, an acceleration (first threshold value) corresponding to a sudden brake / quick steering wheel and an acceleration (second threshold value) equivalent to a collision / accident are set.

Further, (b) in FIGS. 15 to 19 show graphs in which the laser drive current supplied to the laser light source 1 is recorded with time. This graph shows binary values indicating whether the laser light source 1 is turned on (High level) or the laser light source 1 is turned off (Low level). That is, it indicates that the laser light source 1 is either on or off.

(Operation timing chart (1))
FIG. 15 shows a timing chart when collision detection / laser drive is stopped at the timing of pulse drive OFF.

As shown in FIG. 15, when an acceleration corresponding to a sudden brake / quick handle (extinguishing preparation acceleration) is detected in a state where the laser light source 1 is turned on, a predetermined cycle is detected while the extinguishing preparation acceleration is detected. Then, pulse driving is performed in which the laser light source 1 is repeatedly turned on and off. That is, the pulse driving of the laser light source 1 is continuously performed until the sudden brake / quick handle state is released.

When the sudden brake / quick handle state is released, the laser light source 1 is driven normally.

In the state where the laser light source 1 is turned on, when the acceleration corresponding to the sudden brake / quick handle (extinguishing preparation acceleration) is detected again, the laser light source 1 is again pulse-driven. However, when a larger acceleration, that is, an acceleration equivalent to a collision / accident (collision acceleration) is detected in this pulse-driven state, the driving of the laser light source 1 is stopped. After that, even if the acceleration returns to the original state, the driving of the laser light source 1 is stopped, that is, the light is turned off.

As shown in FIG. 15, when a sudden brake / steep handle is detected, a transition is made to pulse drive, and if a pulse is not driven at the time of collision detection, the light is already turned off at the time of collision, and the collision is detected and the light is turned off. Therefore, it is possible to prevent leakage of the laser light to the outside of the light.

(Operation timing chart (2))
FIG. 16 shows a timing chart when collision detection / laser drive is stopped at the pulse drive OFF timing in consideration of the operation delay of acceleration detection / laser light ON / OFF.

Considering the response of the acceleration sensor 3 and the time delay td during which the laser drive circuit 102 receives the response and shifts the laser to pulse drive / light extinction, even if the collision acceleration actually occurs, some laser emission by pulse drive occurs. May be included.

However, since the pulses are driven, as shown in FIG. 16B, at the timing when the light may be physically destroyed (time after the “collision occurrence time” in the chart), it is already The probability that the laser is in the emission stop state and the laser light leakage can be prevented is improved.

Desirably, the pulse driving period T is preferably shorter than the time that humans can perceive (for example, 10 ms corresponding to 50 Hz × 2 = 100 Hz when considering a conventional fluorescent lamp), and it is preferable not to feel flickering or flickering. The delay td due to the response of the acceleration sensor 3 or the laser drive circuit 102 is preferably shorter than the pulse drive period T and as short as possible.

(Operation timing chart (3))
FIG. 17 shows a timing chart when collision detection / laser drive is stopped at the timing of pulse drive ON in consideration of the operation delay of acceleration detection / laser light ON / OFF.

Considering the response of the acceleration sensor 3 and the time delay td when the laser drive circuit 102 receives the response and shifts the laser to pulse driving / extinguishing, laser light emission by pulse driving may occur even if collision acceleration actually occurs. There is sex.

However, since pulse driving is performed, as shown in FIG. 17B, when a collision accident actually occurs, it corresponds to the timing of turning off, or the width of pulse driving is the same as the final driving pulse. After the collision occurs, the laser emission is only one pulse at a maximum until the light falls into a state where the light may be physically destroyed, and the head is in a state where there is a risk of physical destruction or laser leakage. There is a high possibility that the energy of the leaked laser light remains at a minimum even if the light main body is turned off until it reaches reality or is turned on at the time of destruction. That is, since the possibility of turning off the laser light source 1 at the pulse drive timing is generated by pulse driving before the collision is actually detected, the probability of preventing laser light leakage is improved.

(Operation timing chart (4))
FIG. 18 shows another example timing chart in consideration of acceleration detection / operation delay of laser light ON / OFF.

Generally, when pulse driving is performed in the laser light source 1, the average amount of light is reduced compared to when continuous driving is performed. Therefore, as shown in FIG. 18B, since the average light amount is reduced during the pulse driving period of the laser light source 1, it is conceivable to increase the pulse peak value from the normal lighting state in order to compensate for the light amount reduction. . That is, the laser drive circuit 102 drives the laser light source 1 with a laser power larger than the laser power before the pulse drive when the laser light source 1 is pulse-driven for a certain time.

Of course, it is preferable that the current supplied to the laser light source 1 is a current that does not destroy the laser light source 1. However, even if the current is large enough to destroy the laser light source 1 when supplied to the laser light source 1 for a long time, the current is set as long as the laser light source 1 is not destroyed in a short time. Is no problem.

In the pulse driving period, the pulse width of the ON time is shortened and the pulse driving cycle is lengthened so that the instantaneous light current resistance to the laser light source 1 is reduced, the brightness is reduced, and flickering is not perceived by human perception. It is advantageous to set. This is because the temporal probability that the laser is already extinguished when a collision is detected can be increased.

(Operation timing chart (5))
FIG. 19 shows a timing chart of another example in which pulse driving is performed even during normal lighting, and an operation delay of acceleration detection / laser light ON / OFF is taken into consideration.

In the previous figures, the normal driving of the laser light source 1 was assumed to be driven with a continuous current. On the other hand, pulse driving may be considered during normal driving. In such a state of pulse driving, when an accident is avoided, that is, when acceleration corresponding to a sudden brake / steep handle is detected, the driving is switched to a pulse driving with a shorter cycle than the normal driving pulse driving. For this reason, the average light quantity of the pulse drive period after accident avoidance reduces. Accordingly, as shown in FIG. 19B, it is conceivable to increase the pulse peak value from the normal lighting state in order to compensate for the pulse drive period and light amount reduction of the laser light source 1.

In the pulse drive period, the ON time pulse width is set short and the pulse drive cycle is set long so that the instantaneous light current to the laser light source 1 is reduced, brightness is reduced, and flicker is not perceived by human perception. It is advantageous to do so. This is because the temporal probability that the laser is already extinguished when a collision is detected can be increased.

Hereinafter, specific operations when the lighting device 100 having the above-described configuration is mounted on a vehicle as a headlamp will be described in Examples 1 to 11.

In the first to seventh embodiments, drive control of the laser light source 1 in the case of a sudden handle or a sudden brake as a phenomenon occurring in an automobile will be described.

Example 8 describes drive control of the laser light source 1 when the vehicle collides from behind as a phenomenon occurring in an automobile.

Ninth Embodiment A drive control of the laser light source 1 in the case where the vehicle collides from the side as a phenomenon occurring in the automobile will be described as a ninth embodiment.

Example 10 describes drive control of the laser light source 1 when the host vehicle falls as a phenomenon occurring in an automobile.

Example 11 describes drive control of the laser light source 1 when the acceleration sensor detection axis is set in a direction inclined from the rear direction of the host vehicle.

Example 1
FIG. 20 is a diagram schematically illustrating configurations of the illumination device 100 and the automobile 200 according to the first embodiment.

The illumination device 100 includes a headlamp unit 101 and a laser drive circuit 102 as shown in FIG. The headlamp unit 101 includes at least the laser light source 1, the condenser lens 4, the housing 300, the phosphor 301, the laser light cut filter 302, and the acceleration sensor 3. The laser driving circuit 102 is as described above, and detailed description thereof is omitted.

Next, the automobile 200 includes the lighting device 100 including the headlamp unit 101 at the head portion.

In addition, the headlamp unit 101 may be applied to a traveling headlamp (high beam) for an automobile, or may be applied to a passing headlamp (low beam).

Each component of the headlamp unit 101 will be described.

(Laser light source 1)
The laser light source 1 is a light source composed of a single LD chip (semiconductor laser) 11 as shown in FIG. 3 or a plurality of LD chips 11 connected to each other.

Further, the plurality of LD chips 11 may be connected to each other in series, may be connected to each other in parallel, or may be used in combination with series and parallel. In this embodiment, the case where the laser light source 1 is composed of a single LD chip 11 and the case where it is composed of four LD chips 11 connected in series (semiconductor laser group) will be described.

The single LD chip 11 may be, for example, one having a high power of about 5 to 10 W as an optical output of one chip that oscillates a 405 nm (blue-violet) laser beam.

In addition, as the LD chip 11, one having one light emitting point per chip (one chip and one stripe) may be used, or one having a plurality of light emitting points (one chip plural stripes or plural chips: 1 for example) Stripe, aggregate of one chip with an optical output of 1.0 W, operating voltage of about 5 V, and current around 0.7 A), or each chip with the same rating as above (stem) A plurality of may be used. In this embodiment, it is assumed that the LD chip 11 having a high output (about 5 to 10 W as an optical output) with one stripe per chip is used.

The wavelength of the laser light oscillated by the LD chip 11 is not limited to 405 nm, and the wavelength from the near ultraviolet region to the blue region (350 nm to 460 nm or less), more preferably from the near ultraviolet region to the blue-violet region (350 nm to 420 nm). Any material having a peak wavelength (emission peak wavelength) in the range may be used. This is because short-wavelength light excites the phosphor more easily than long-wavelength light (the energy as light is high), so the phosphor of phosphor 301 described later (including conversion efficiency from laser light to fluorescence) This is because the range of selection is widened, and if the visible light and the wavelength of the laser light used as illumination are separated from each other, the optical filter member can easily distinguish the two, and the amount of the laser light mixed with the illumination light. This is because the safety can be further increased by reducing the amount of slag.

However, even if the wavelength component of the laser beam is used, the safety of the laser beam can be ensured by reducing the coherency of the laser beam by devising the phosphor material used for the phosphor 301 described later and the optical components. The range of wavelength selection is widened.

Further, when an oxynitride-based or nitride-based phosphor described later is used as the phosphor of the phosphor 301, the light output of the LD chip 11 is 1 W or more and 20 W or less, and the laser irradiated to the phosphor 301 The light density of the light is preferably 0.1 W / mm ² or more and 50 W / mm ² or less. If the light output is in this range, it is possible to achieve the luminous flux and brightness required for the vehicle headlamp 10, and it is possible to prevent the phosphor 301 from being extremely deteriorated by the high output laser light. That is, it is possible to realize a light source having a long lifetime while having a high luminous flux and a high luminance.

However, when the phosphor 301 has excellent heat resistance, for example, a nanoparticle phosphor described later is used as the phosphor 301, the light density of the laser light applied to the phosphor 301 is as follows. , Greater than 50 W / mm ² . The phosphor 301 is not limited to the one using a nanoparticle phosphor described later, and if the one having excellent heat resistance is used, the light output of the LD chip 11 or the light of the laser beam irradiated on the phosphor 301 is used. The density may be larger than the above value, and when the phosphor 301 has high conversion efficiency from laser light to visible light, or when the required optical output of visible light is at least good, the LD chip 11 The light output and the light density of the laser light to the phosphor 301 may be smaller than the above values.

(Condenser lens 4)
The condenser lens 4 adjusts the area (irradiation area) of the spot of the laser light L0 irradiated to the phosphor 301 in the housing 300. According to the condensing lens 4, since the area of the spot of the laser beam L0 irradiated to the phosphor 301 can be adjusted, the light emission efficiency of the phosphor 301 can be adjusted.

In addition, it is preferable that the condensing lens 4 makes the area of the spot of the laser beam L0 smaller than the area of the surface (light irradiation surface) on the side where the excitation light of the phosphor 301 is irradiated. Thereby, the fluorescence (side emission fluorescence) emitted from the side surface sharing the side with the light irradiation surface of the phosphor 301 is reduced. Therefore, the ratio of the fluorescence emitted from the light irradiation surface of the phosphor 301 to the fluorescence emitted from the entire surface of the phosphor 301 can be increased. Moreover, although the material of the condensing lens 4 can illustrate quartz, for example, it is not limited to this.

(Phosphor 301)
The phosphor 301 generates fluorescence by irradiating the laser beam L0 generated from the laser light source 1, and includes a phosphor that emits light upon receiving the laser beam L0. Specifically, the phosphor 301 is one in which the phosphor is dispersed inside the sealing material, or one in which the phosphor is solidified, and further fixed on a substrate such as a metal. . It can be said that the phosphor 301 is a so-called wavelength conversion element for converting the laser light L0 into fluorescence. In this embodiment, the phosphor 301 is arranged in a direction (right side in the drawing) in which fluorescence is desired by the housing 300. It is arranged at a position where it emits with a desired light intensity distribution (for example, the focal point if the inner surface of the housing has a parabolic shape).

In the present embodiment, the shape of the phosphor 301 is a cylindrical shape (disk shape) with a diameter of the bottom circle of 2 mm. However, the size and shape are not limited to this, and any size and various shapes can be used. You can choose. Examples of shapes other than the disc shape include a prismatic shape and an elliptical column shape.

In addition, the thickness along the irradiation direction of the laser beam L0 in the portion that substantially emits fluorescence excluding the substrate or the like of the phosphor 301 is 1 mm in this embodiment, but is 0.015 mm or more and 1.5 mm. The following is preferable. If the thickness of the above portion of the phosphor 301 exceeds 1.5 mm, the path length of the transmitted light that passes through the phosphor 301 becomes too long, and the generation efficiency of the fluorescence in the phosphor 301 decreases. On the other hand, if the thickness of the fluorescent portion of the phosphor 301 is less than 0.015 mm, the intensity of the fluorescence generated from the phosphor 4 becomes too weak. However, the thickness may be outside the above numerical range as long as a desired light emission (fluorescence) amount can be obtained.

Next, as the phosphor included in the phosphor 301, for example, an oxynitride phosphor (eg, sialon phosphor) or a III-V compound semiconductor nanoparticle phosphor (eg, indium phosphorus: InP) is used. Can be used. These phosphors have high heat resistance to the high-power (and / or light density) laser light L0 emitted from the LD chip 11, and can suppress the deterioration of the phosphor 301. However, the phosphor 301 is not limited to those described above, and may be another phosphor such as a nitride-based phosphor.

In addition, it is stipulated by laws and regulations in some countries and regions that the illumination light L1 of the headlamp 100 must be white having a predetermined range of chromaticity. Therefore, the phosphor 4 includes a phosphor selected so that the illumination light L1, that is, visible light is white.

For example, when blue, green and red phosphors are included in the phosphor 301 and irradiated with a laser beam L0 of 405 nm, white light is generated. In the case where there is no provision in the law or the like regarding the color of the illumination light L1, or when there is a provision for another chromaticity, the selection of the light emitter 4 is specified as one in which the illumination light L1 is white as described above. It is not something.

The sealing material of the phosphor 301 is, for example, a glass material (inorganic glass, organic / inorganic hybrid glass), or a resin material such as silicone resin. Alternatively, glass may be used. The sealing material is preferably highly transparent, and when the laser beam has a high output or the density of the irradiation intensity of the laser beam on the phosphor 301 is high, a material having high heat resistance is preferable.

(Laser light cut filter 302)
The laser light cut filter 302 is a transparent resin plate that covers the light emitting surface of the housing 300. The laser light cut filter 302 blocks the coherent component included in the laser light L0 from the laser light source 1 and converts the incoherent component included in the laser light and the laser light L0 in the phosphor 301. It is preferable to form with the material which permeate | transmits the produced | generated white light.

For example, if the wavelength of light emitted from the laser light source 1 is 410 nm, the laser light cut filter 302 absorbs or reflects light having a wavelength shorter than 410 nm and prevents the laser light from leaking outside the apparatus. Note that the wavelength of light blocked by the laser light cut filter 302 may be determined in consideration of the hue of visible light and the wavelength and light amount of the laser light L0.

In addition, by sealing the housing 300 with the laser light cut filter 302, intrusion of moisture, dust, or the like in the external environment can be prevented.

The inner surface 300a of the casing 300 is formed so as to reflect the fluorescence converted from laser light into visible light by the phosphor 301 and guide it to the laser light cut filter 302 provided in the opening of the casing 300. Has been. In this laser light cut filter 302, visible light is transmitted and laser light is reflected. For this reason, only visible light is emitted to the outside of the headlamp unit 101, and laser light is not emitted.

The acceleration sensor 3 is installed in the casing 300. The acceleration sensor 3 detects the acceleration of the housing 300, that is, a sudden movement, and transmits the acceleration signal S5 to the laser driving circuit 102.

That is, in the headlamp unit 101 configured as described above, first, the laser light is condensed from the laser light source 1 by the condenser lens 4 and irradiated onto the phosphor 301.

Next, visible light (fluorescence) resulting from the laser light is generated from the phosphor 301. This laser beam is blue-violet with a wavelength of 405 nm here, and the phosphor 301 emits light having a longer wavelength. The wavelength spectrum of the light from the phosphor 301 may be set arbitrarily.

Subsequently, the visible light from the phosphor 301 is changed in the right side of the figure in the housing 300 in the direction of the emission surface, emitted to the outside, and becomes irradiation light.

Note that the means for changing the direction of visible light in the housing 300 is the curved shape of the inner surface of the housing.

Also, the inner surface 300a of the housing 300 has a high reflectivity of mirror surface or white paint or light (electromagnetic wave) equivalent thereto.

An optical member that transmits the visible light in the direction of the visible light emission surface of the housing 300 and reduces the laser light amount to a safe level when visually observed, for example, a wavelength shorter than 410 nm. A laser beam cut filter 302 that blocks light is provided. Note that the wavelength to be cut is determined in consideration of the hue of visible light, the amount of laser light, and the wavelength.

Here, the laser light source 1 is supplied with the laser drive current C0 from the laser drive circuit 102 and is turned on.

The laser drive circuit 102 includes a laser control signal S0 including at least one of an instruction for turning on / off the laser and a light amount (or voltage, current) instruction value at the time of turning on / off from an external control unit such as an ECU (electronic control unit). Is given. The laser drive circuit 102 drives the laser light source 1 based on the laser control signal S0.

As described above, the casing 300 of the headlamp unit 101 is provided with the acceleration sensor 3, and when detecting that the acceleration exceeds the first threshold, the laser driving circuit 102 performs a laser light source for a certain period of time. 1 is pulse driven. The pulse drive peak value may be the same as or different from the normal state. The acceleration sensor 3 may be provided not at the casing 300 of the headlamp unit 101 but at the topmost part (bumper or the like) of the vehicle. In this case, the collision can be detected earlier and the light can be turned off.

Next, when it is detected that the acceleration has exceeded another second threshold value during the pulse driving period resulting from exceeding the first threshold value, the laser driving circuit 102 stops driving the laser light source 1. And turn it off.

When acceleration exceeding the first threshold is not detected during the pulse driving period due to exceeding the first threshold, the normal lighting is restored.

(Action / Effect)
In the lighting device 100 having the configuration of the first embodiment, since the acceleration sensor 3 is used, the temporal second-order differentiation of the displacement (= damage) of the headlamp unit 101 main body is detected. The laser can be turned off as soon as it is actually destroyed, and as a result, safety can be improved.

Further, since the laser light source 1 is pulse-driven when a sudden brake / steep handle that is an avoidance operation before the accident is detected, even if an accident occurs despite the avoidance operation, the headlamp unit 101 is already damaged. There is a timing when the light is extinguished, the probability of preventing laser leakage is improved, and safety is improved.

(Example 2)
FIG. 21 is a diagram schematically illustrating configurations of the illumination device 100 and the automobile 200 according to the second embodiment. For convenience of explanation, members having the same functions as those in the drawings described in the first embodiment are denoted by the same reference numerals and description thereof is omitted.

In the headlamp unit 101 of the illumination device 100 according to the second embodiment, as shown in FIG. 21, a housing 310 is employed instead of the housing 300 of the headlamp unit 101 of the first embodiment.

That is, the casing 310 of the headlamp unit 101 has a shape obtained by cutting a parabolic (parabolic) rotating body in half in the longitudinal axis direction from the bullet shape of the first embodiment. An irradiation position of the laser beam on the phosphor 311 is determined near the focal point of the housing 310.

Also, the inner surface 310a of the housing 310 is a mirror surface or white paint, and has a high light reflectance.

The phosphor 311 receives laser light and emits infrared rays (having different wavelengths). For example, infrared rays having a wavelength near 1000 nm are emitted.

A wavelength conversion (eg, SHG · Second Harmonic Generation) element and a laser light cut filter 312 are provided in the direction of the visible light emission surface of the housing 310, and the infrared light is used as visible light. Visible light near the wavelength of 500 nm, which is half the light, is emitted to the outside.

The laser light from the laser light source 1 is, for example, bluish purple (405 nm), and the laser light cut filter 312 absorbs or reflects light having a wavelength shorter than 410 nm, for example, to prevent emission to the outside. Also in this case, the indicated wavelength is determined in consideration of the hue of visible light and the laser wavelength / light quantity.

The laser drive circuit 102 is supplied with a laser control signal S0 including at least one of an instruction for turning on / off the laser and an instruction value for lighting light quantity (or voltage or current) from an external control unit such as an ECU. The laser drive circuit 102 drives the laser light source 1 based on the laser control signal S0.

As described above, the casing 300 of the headlamp unit 101 is provided with the acceleration sensor 3, and when detecting that the acceleration exceeds the first threshold, the laser driving circuit 102 performs a laser light source for a certain period of time. 1 is pulse driven.

(Action / Effect)
In the illumination device 100 having the configuration according to the second embodiment, the parabolic housing 310 is adopted as compared with the illumination device 100 according to the first embodiment. Therefore, the light emitted from the housing 310 is parallel to the emission surface. It is easy to install, it is almost parallel when viewed from the exit surface, and it can not only diffuse and illuminate the target position efficiently, but it also has a half-cut shape of the curved rotating body as the housing 310, so it is easy to install, Heat generation of the phosphor 311 that receives the light of the high-power semiconductor laser is easily performed quickly through the housing 310.

Furthermore, since the phosphor 311 is an infrared phosphor, the efficiency of the infrared phosphor + wavelength conversion element (+ laser light cut filter) is higher than that of the visible light phosphor of the first embodiment. In this case, there is an advantage that the degree of freedom of selection increases.

(Example 3)
FIG. 22 is a diagram schematically illustrating configurations of the illumination device 100 and the automobile 200 according to the third embodiment. For convenience of explanation, members having the same functions as those in the drawings described in the first and second embodiments are denoted by the same reference numerals and description thereof is omitted.

In the headlamp unit 101 of the illumination device 100 according to the third embodiment, as shown in FIG. 22, a casing 300 having the same shape as the casing 300 of the headlamp unit 101 of the first embodiment is employed.

In the third embodiment, fluorescent light (visible light) that is transmitted through the fluorescent material with laser light is used. For this reason, the phosphor 301 is installed in the housing 300 via the phosphor holding member 303 so that the laser light transmission surface is parallel to the visible light emitting surface of the housing 300.

The laser light source 1 is blue-violet light having a wavelength of 405 nm as in the first and second embodiments. The output light of the laser light source 1 is transmitted through the phosphor 301, and the phosphor 301 emits visible light based on the light energy when transmitting the laser beam. The phosphor 301 is prepared so that the emission wavelength has an arbitrary color.

In order to adjust the condensing state of the laser light source 1, a condensing lens 4 for adjusting the degree of condensing may be inserted between the laser light source 1 and the phosphor 301. The condensing lens 4 is not limited to condensing, but may be a concave lens as long as it is adjusted to diverge.

A shading process may be optionally provided around the phosphor 301 so as to prevent leakage of the laser beam even when the laser beam slightly deviates from the phosphor 301. This may be provided with a member that does not transmit light, such as a metal film or a metal piece, or may be painted. For example, a light shielding process portion 304 subjected to a light shielding process may be formed in a region other than the phosphor 301 of the phosphor holding member 303.

The inner surface 300a of the casing 300 is a mirror surface, and has a curved surface so as to collect light in a target direction (right direction in the figure).

A protective glass plate is provided on the visible light emitting surface of the casing 300 in order to protect the inside from the external environment (humidity, dust, etc.).

When the configuration of the headlamp unit 101 is “phosphor transmission type” as in the third embodiment, the amount of laser light that appears in the exit surface direction compared to the “phosphor reflection type” in the first and second embodiments. However, it is preferable that the protective glass plate be the laser light cut filter 302 when safety is taken into consideration. If the light emission wavelength of the laser light source 1 is 405 nm, it is preferable that the laser light cut filter 302 cut off short wavelengths of about 410 nm or 420 nm or less. That is, when the phosphor 301 emits blue light, the emitted light is close to white and is recognized as high-quality light. Therefore, it is desirable to block only the laser light component without blocking the light having a very long wavelength. The wavelength of the laser light to be blocked by the laser light cut filter 302 may be determined in consideration of the hue of visible light and the laser light quantity / wavelength.

(Action / Effect)
Since the headlamp unit 101 according to the third embodiment is a transmissive type as shown in FIG. 22, the laser light that is not shielded by the light-shielding portion 304 passes through the phosphor 301 and is mostly fluorescent (visible). Light). As a result, there is little laser light leaking to the emission surface of the headlamp unit 101, and visual safety is improved.

Further, when the laser light cut filter 302 is provided, it can be used even if the laser light blocking ability is slightly low.

Example 4
FIG. 23 is a diagram schematically illustrating configurations of the illumination device 100 and the automobile 200 according to the fourth embodiment. For convenience of explanation, members having the same functions as those in the drawings explained in the first to third embodiments are given the same reference numerals and explanation thereof is omitted.

23. As shown in FIG. 23, the headlamp unit 101 of the lighting device 100 according to the fourth embodiment employs a casing 310 having the same shape as the casing 310 of the headlamp unit 101 according to the second embodiment.

That is, the housing 310 of the present embodiment has a shape obtained by cutting a parabola (a parabolic rotating body) in half in the longitudinal axis direction.

The laser light source 1 is disposed at the focal position of the parabola of the housing 310 as shown in FIG.

Further, a phosphor is applied to a portion of the inner surface 310a of the housing 310 opposite to the visible light emitting surface (right side in the figure), and the light from the laser light source 1 is irradiated with the phosphor as a target. The phosphor is formulated so as to obtain light of an arbitrary color. The other inner surface 310a of the housing 310 is made of a mirror surface or white paint, and is made of a material that maintains high light reflectance or absorbs laser light.

When the laser emitted from the laser light source 1 is, for example, bluish purple (405 nm), and the amount of light reflected on the phosphor surface is concerned with safety when viewed from the emission surface, the visible light emission surface of the housing 310 is used. Is provided with a laser beam cut filter 312.

The laser light cut filter 312 absorbs or reflects light having a wavelength shorter than 410 nm, for example, to prevent emission to the outside. If there is no problem in safety, a protective glass plate or other member may be provided on the visible light emitting surface of the housing 310 instead of the laser light cut filter 312.

The wavelength of the laser beam to be blocked by the laser beam cut filter 312 may be determined in consideration of the hue of visible light and the laser light quantity / wavelength.

(Action / Effect)
In the headlamp unit 101 according to the fourth embodiment, the phosphor is not disposed in the housing 310, but a fluorescent component is applied to the inner surface of the housing 310 so as to have the same function as the phosphor. Yes. Therefore, the laser light emitted from the laser light source 1 is reflected by the inner surface 310a of the housing 310 and becomes visible light. For this reason, it becomes possible to provide the laser light source 1 inside the housing 310, and even if the position of the laser light source 1 fluctuates due to some factor, the possibility that the laser light stays in the housing 310, that is, the safety increases.

Since the phosphor is applied to the housing 310 and irradiated with laser light, the phosphor is excellent in heat dissipation.

Also, since the phosphor does not have to be prepared as a separate substrate, the number of parts is reduced.

In addition, by providing the housing 310 with a laser light absorbing member other than the phosphor coating portion, the leakage of the laser light can be further reduced, and the safety is further improved.

(Example 5)
FIG. 24 is a diagram schematically illustrating configurations of the illumination device 100 and the automobile 200 according to the fifth embodiment. For convenience of explanation, members having the same functions as those in the drawings described in the first to fourth embodiments are denoted by the same reference numerals and description thereof is omitted.

As shown in FIG. 24, the headlamp unit 101 of the lighting device 100 according to the fifth embodiment employs a casing 310 having the same shape as the casing 310 of the headlamp unit 101 according to the second embodiment.

The phosphor 311 is arranged so that the irradiation position of the laser beam comes near the focal point of the parabola of the housing 310.

The phosphor 311 receives laser light and emits visible light. The phosphor 311 is generated by preparing a phosphor material so that the emitted light becomes a desired one.

Further, the inner surface 310a of the casing 310 is a mirror surface or white paint, and has a high light reflectance.

Furthermore, a protective glass plate or a laser light cut filter 312 for protecting the inside from humidity and dust from the outside is provided on the visible light emitting surface (right direction in the figure) of the housing 310.

The protective glass plate has at least one pattern of unevenness, granularity, lattice, or glassy pattern formed on at least one of the back surface and the front surface to reduce the density on the laser light emission surface, Alternatively, the coherency is lowered to increase the safety when visually observed.

For further safety, the protective glass plate is preferably a laser light cut filter 312.

When the laser irradiated from the laser light source 1 is, for example, bluish purple (405 nm), the laser light cut filter 312 absorbs or reflects light having a wavelength shorter than 410 to 420 nm, for example, and prevents emission to the outside. Designed to.

It should be noted that the wavelength of the laser beam to be blocked by the laser beam cut filter 312 may be determined in consideration of the hue of visible light and the laser light quantity / wavelength.

The housing 310 of the headlamp unit 101 is provided with the acceleration sensor 3 as described above, and when detecting that the acceleration exceeds the first threshold, the laser driving circuit 102 performs a laser light source for a certain period of time. 1 is pulse driven.

(Action / Effect)
According to the headlamp unit 101 according to the fifth embodiment, since the leaking laser light is diffused on the emission surface, the density or coherency of the laser light is lowered, and the safety when visually observed can be improved.

(Example 6)
FIG. 25 is a diagram schematically illustrating configurations of the illumination device 100 and the automobile 200 according to the sixth embodiment. For convenience of explanation, members having the same functions as those in the drawings explained in the first to fifth embodiments are given the same reference numerals and explanation thereof is omitted.

In the headlamp unit 101 of the lighting device 100 according to the sixth embodiment, as shown in FIG. 25, a casing 300 having the same shape as the casing 300 of the headlamp unit 101 of the third embodiment is employed.

However, as shown in FIG. 25, the housing 300 is provided with an optical fiber 305 from the visible light emitting surface of the phosphor 301 to the visible light emitting surface of the housing 300. The configuration of the headlamp unit 101 is different from that of the headlamp unit 101 of the third embodiment.

The laser light source 1 is blue-violet light having a wavelength of 405 nm as in the third embodiment. The output light is transmitted through the phosphor 301, and the phosphor 301 emits visible light based on the light energy when transmitting the laser beam. The phosphor 301 is prepared so that the emission wavelength has an arbitrary color.

Conversely, in order to adjust the degree of condensing visible light, the condensing lens 4 may be arranged on the visible light emitting surface side (right side) of the housing 300 from the phosphor 301 of FIG.

Visible light from the phosphor 301 is transmitted to the visible light emission surface of the housing 300 through the optical fiber 305. Since the optical fiber 305 can be bent, the degree of freedom of arrangement of the laser light source 1 and the phosphor 301 is increased.

It should be noted that a protective glass plate is provided on the visible light emitting surface of the housing 300 in order to protect the inside from the external environment (humidity, dust, etc.).

As in the sixth embodiment, when the configuration of the headlamp unit 101 is “phosphor transmission type”, the amount of laser light appearing in the direction of the emission surface compared to the “phosphor reflection type” in the first and second embodiments. However, it is preferable that the protective glass plate be the laser light cut filter 302 when safety is taken into consideration. If the light emission wavelength of the laser light source 1 is 405 nm, it is preferable that the laser light cut filter 302 cut off short wavelengths of about 410 nm or 420 nm or less. That is, when the phosphor 301 emits blue light, the emitted light is close to white and is recognized as high-quality light. Therefore, it is desirable to block only the laser light component without blocking the light having a very long wavelength. The wavelength of the laser light to be blocked by the laser light cut filter 302 may be determined in consideration of the hue of visible light and the laser light quantity / wavelength.

(Action / Effect)
Since the headlamp unit 101 according to the sixth embodiment is a transmissive type as shown in FIG. 25, the laser light that has not been shielded by the light shielding processing portion 304 passes through the phosphor 301. As a result, there is little laser light leaking to the emission surface of the headlamp unit 101, and visual safety is improved.

Further, even when the laser light cut filter 302 is provided, it can be used even if the laser light blocking ability is slightly low.

Furthermore, since the optical fiber 305 is used for the optical path for guiding visible light inside the housing 300, the optical path can be easily changed. Thereby, the effect that the freedom degree of the positional relationship with the emission surface of the visible light of the laser light source 1, the fluorescent substance 301, and the housing | casing 300 increases is acquired.

(Example 7)
FIG. 26 is a diagram schematically illustrating configurations of the illumination device 100 and the automobile 200 according to the seventh embodiment. For convenience of explanation, members having the same functions as those in the drawings explained in the first to sixth embodiments are given the same reference numerals and explanation thereof is omitted.

In the headlamp unit 101 of the illumination device 100 according to the seventh embodiment, as shown in FIG. 26, a casing 300 having the same shape as the casing 300 of the headlamp unit 101 of the third embodiment is employed.

As in the seventh embodiment, when the configuration of the headlamp unit 101 is “phosphor transmission type”, the amount of laser light that appears in the direction of the emission surface compared to the “phosphor reflection type” in the first and second embodiments. Can be expected to be small, but in order to remove the laser beam having a high coherency component that has passed through without being reflected by the internal particles of the phosphor 301, it is necessary to insert a polarization (polarization) filter 306 on the exit surface. preferable.

The polarization filter 306 may be a filter that blocks the polarization (polarization) in the same direction as the polarization plane of the light emitted from the laser light source 1 in advance.

(Action / Effect)
Since the headlamp unit 101 according to the seventh embodiment is a transmissive type as shown in FIG. 26, the laser light that has not been shielded by the light shielding processing portion 304 passes through the phosphor 301. As a result, there is little laser light leaking to the emission surface of the headlamp unit 101, and visual safety is improved.

In Examples 1 to 7 so far, the external leakage of laser light in the headlamp unit 101 is reduced on the assumption that a sudden brake for avoiding an accident or a sudden handle is turned off while driving a car. In the eighth embodiment described below, an example in which external leakage of laser light in the headlamp unit 101 when another person's automobile collides with the own automobile from the minus direction will be described.

(Example 8)
FIG. 27 is a diagram schematically illustrating configurations of the illumination device 100 and the automobile 200 according to the eighth embodiment. For convenience of explanation, members having the same functions as those in the drawings explained in the first to seventh embodiments are given the same reference numerals and explanation thereof is omitted.

The headlamp unit 101 of the illumination device 100 according to the eighth embodiment has the same structure as the headlamp unit 101 of the second embodiment as shown in FIG.

In the present embodiment, it is assumed that the vehicle is not only collided with a car that the driver is driving (hereinafter referred to as the own vehicle), but is also collided with another vehicle (hereinafter referred to as another vehicle).

Therefore, when the collision of the vehicle itself is set as the + j direction output of the acceleration sensor 3, the same two-stage thresholds (first threshold value, second threshold value) as in the previous Examples 1 to 7 are provided in the + j direction. Pulse driving and extinguishing operation are performed. That is, in the case of the + j direction output of the acceleration sensor 3, the same laser light extinction control as in the first to seventh embodiments is performed.

Conversely, if the acceleration due to a rear-end collision from another vehicle is output in the -j direction, a separate threshold is also set in the -j direction, and when this exceeds the -j direction, the light is turned off. The acceleration sensor 3 that detects the rear-end collision may use an acceleration sensor for collision detection, or may be separately provided as an acceleration sensor for rear-end collision detection.

Here, when the acceleration sensor for collision detection is provided, the acceleration sensor for collision detection may be provided in the rear part of the automobile 200 or in the vicinity of the casing of the headlamp unit 101.

When the rear-end collision detection acceleration sensor is provided in the rear part of the automobile 200, if it is turned off by a minor rear-end collision, it is dangerous to continue to turn off in spite of being able to run on its own, considering nighttime, etc. It is unlikely that damage to the headlight located in front of the vehicle due to damage at the rear of the vehicle will be extinguished due to a sudden start (ie, a start that produces a sudden acceleration in the forward direction corresponding to the -j direction). In view of the inconvenience, the acceleration threshold value “1-1” when starting pulse driving based on the output of the acceleration sensor for collision detection is greater than the acceleration corresponding to sudden braking. Preferably. Alternatively, when acceleration from the rear is detected, pulse driving is not performed and the lamp is normally lit unless it is a large acceleration having an absolute value exceeding the absolute value of the threshold value “2-1” described below. Although there is an option to do this, for the sake of safety, it is assumed here that the operation is temporarily switched to pulse driving.

Further, the threshold value “2-1” for turning off the light is set to have an absolute value equal to or higher than the second threshold value corresponding to the collision, and the rear part of the automobile 200 is greatly damaged, so that the impact is transmitted to the headlamp part 101. It is also preferable to turn off the light only when it is done.

Alternatively, if the acceleration sensor provided in the main body (housing) of the headlamp unit 101 also detects the acceleration in the minus (rear impact) direction, the light is turned off when detecting the acceleration whose absolute value in the minus direction exceeds the second threshold value, or The pulse driving operation may be performed when the absolute value in the minus direction of the acceleration due to the rear-end collision exceeds the first threshold value. The drive control of the laser light source 1 by the acceleration detection in this case is as shown in the timing chart of FIG.

As shown in FIG. 28 (a), the acceleration detection polarity corresponding to the sudden braking / steering handle and the acceleration detection polarity corresponding to the rear-end collision from the rear are in the positive and negative directions.

The housing 310 of the headlamp unit 101 is provided with the acceleration sensor 3 as described above. When detecting that the acceleration in the + direction exceeds the first threshold value, the laser driving circuit 102 performs a certain period of time. The laser light source 1 is pulse-driven.

Next, when it is detected that the acceleration in the + direction exceeds another second threshold value during the pulse driving period resulting from exceeding the first threshold value, the laser driving circuit 102 detects the laser light source 1. Stop driving and turn it off.

When the acceleration sensor 3 detects the acceleration in the negative direction and the absolute value of the detected value exceeds the absolute value of the first threshold value or the absolute value of the threshold value “1-1”, the laser driving circuit 102 is detected. The pulsed drive of the laser light source 1 for a certain time.

Next, during the pulse drive period resulting from the absolute value of the detected acceleration exceeding the absolute value of the first threshold or the threshold “1-1”, the absolute value of the acceleration in the negative direction is When it is detected that the absolute value of another second threshold value or the absolute value of the threshold value “2-1” has been exceeded, the laser driving circuit 102 stops driving the laser light source 1 and turns it off.

The absolute value of the first threshold value or the absolute value of the threshold value “1-1” during the pulse driving period due to exceeding the absolute value of the first threshold value or the threshold value “1-1”. When acceleration having an absolute value exceeding the value is no longer detected, normal lighting is restored.

(Action / Effect)
In the illumination device 100 according to the eighth embodiment, it is possible to prevent laser light leakage due to headlamp breakage even when a rear-end collision is caused by another vehicle.

In the first to eighth embodiments so far, depending on the acceleration in the longitudinal direction of the vehicle detected by the sudden braking at the time of collision of the own vehicle due to the accident or the rear-end collision of the own vehicle or avoiding the accident. The laser light source 1 has been pulse-driven or stopped. However, in Example 9 below, the side collision of the other vehicle against the own vehicle, the side collision to the object due to the slip of the own vehicle, and the accident avoidance An example will be described in which the laser light source 1 is pulse-driven or stopped according to the acceleration in the lateral direction of the vehicle detected by the sudden handle.

Example 9
FIG. 29 is a diagram schematically illustrating configurations of the illumination device 100 and the automobile 200 according to the ninth embodiment. For convenience of explanation, members having the same functions as those in the drawings explained in the first to eighth embodiments are given the same reference numerals and explanation thereof is omitted.

The headlamp unit 101 of the illumination device 100 according to the ninth embodiment has the same structure as the headlamp unit 101 of the eighth embodiment, as shown in FIG.

Therefore, basically, the same control as in the eighth embodiment is performed, but in this embodiment, the acceleration sensor 3 detects the acceleration in the lateral direction 313 of the vehicle.

That is, if the acceleration equivalent to the steep steering wheel (first threshold value in the lateral direction) that is going to avoid an accident is detected, the headlamp unit 101 is switched to pulse driving. Similarly, if the acceleration in the lateral direction is equal to or greater than the first threshold value for the spin during traveling, the process shifts to pulse driving. Note that pulse driving may be performed even in a normal lighting state. The same applies to other embodiments.

Further, when an acceleration exceeding the second threshold value in the lateral direction corresponding to the acceleration equivalent to the side collision is detected, the laser driving circuit 102 cuts off the laser driving current C0 to the laser light source 1 and turns it off.

Further, in this embodiment, as in the embodiments so far, the detection of the longitudinal direction of the vehicle (collision, rear-end collision) is performed at the same time, and if it is determined that it is in any critical state according to the longitudinal or lateral acceleration, Perform actions according to the critical condition.

For example, if the acceleration in the vehicle longitudinal direction is small and less than the first threshold, but the lateral acceleration exceeds the lateral first threshold equivalent to a steep handle, pulse driving as a light-off preparation stage, the longitudinal acceleration is low even if the lateral acceleration is small. It is conceivable to perform control so that the light is extinguished when the second threshold value is exceeded.

(Action / Effect)
According to the illumination device 100 according to the ninth embodiment, it is possible to prevent laser light leakage due to breakage of the headlamp unit 101 even in the case of a rear-end collision from another vehicle or a side collision with an object.

In Examples 1 to 9 so far, the acceleration in the longitudinal direction of the vehicle detected by the sudden braking at the time of collision of the own vehicle due to an accident or the rearward collision of the own vehicle or when the accident is avoided, the own vehicle The laser light source 1 is pulse-driven or stopped according to the side collision of the other vehicle against the vehicle, the side collision to the object due to the slip of the own vehicle, the acceleration in the side direction of the vehicle detected by the sudden handle for avoiding the accident. In Example 10 below, an example in which the laser light source 1 is pulse-driven or stopped according to acceleration in the vertical direction of the vehicle detected by the vehicle falling or riding on the vehicle is described. Will be described.

(Example 10)
FIG. 30 is a diagram schematically illustrating configurations of the illumination device 100 and the automobile 200 according to the tenth embodiment. For convenience of explanation, members having the same functions as those in the drawings explained in the first to ninth embodiments are given the same reference numerals and explanation thereof is omitted.

The headlamp unit 101 of the illumination device 100 according to the tenth embodiment has the same structure as the headlamp unit 101 of the eighth embodiment as shown in FIG.

Therefore, basically, the same control as that in the eighth embodiment is performed, but in this embodiment, the acceleration sensor 3 detects the acceleration in the vertical direction 314 of the vehicle.

In this embodiment, when the acceleration in the vertical direction of the vehicle (the vertical direction in the figure) is a large value (a value larger than a certain threshold value), it can be assumed that the vehicle falls or collides from above the falling object (both are destructive). When the acceleration is a small value (a value smaller than a certain threshold value), it can be assumed that the acceleration is caused by a step or road surface unevenness. When the former is detected, the laser light source 1 is turned off, and in the latter case, the laser light source 1 is turned off. Control to pulse drive.

For example, as shown in FIG. 30, assuming an accident in which the automobile 200 falls from the step 400a of the road 400, if a downward acceleration around 1G is detected, the possibility of free fall is assumed. In preparation for impact, enter the light-off preparation stage. That is, the laser light source 1 is pulse-driven.

Also, regarding the impact at the time of falling, it is assumed that higher acceleration is applied than at the time of dropping, and the head lamp unit 101 main body is suspected to be damaged, so the laser light source 1 is immediately turned off.

Similarly, in the upward collision of the falling object against the own vehicle, the laser light source 1 is turned off when the acceleration that damages the main body of the headlamp unit 101 is detected. In this case, there is no need or time for pulse driving.

Furthermore, for a rough road surface or level difference, an acceleration that exceeds the first threshold in the vertical direction (but does not exceed the second threshold that is the impact (light-off) acceleration in the vertical direction) is determined in advance within a certain time. If it occurs within a predetermined number of times, pulse driving is performed for a certain period of time as a preparatory stage "assuming extinction" for a certain period of time each time it is detected that the first threshold value has been exceeded.

In addition, when driving on rough roads or steps, acceleration exceeding the first threshold in the vertical direction (not exceeding the acceleration equivalent to the second threshold in the vertical direction) occurs more than a predetermined number of times within a certain period of time. Since the end of the last pulse driving of the predetermined number of times, the normal lighting state is maintained even after the first threshold value is exceeded. However, when acceleration exceeding the second threshold is detected, the light is naturally turned off.

Alternatively, when acceleration exceeding the first threshold value in the vertical direction is detected at a substantially constant cycle, if it can be detected that the occurrence of a substantially constant cycle is detected, pulse driving for preparing for extinction is performed when it is detected. Stop and shift to normal lighting.

In the up and down direction, the impact should be relieved considerably by the suspension of the car etc., so if the acceleration sensor detects a large acceleration, it can be assumed that it is a really big accident such as a fall or a collision with a falling object, so it turns off . In other words, the threshold value in the vertical direction may be a large value that is less sensitive than the front-back and side directions.

(Action / Effect)
According to the illumination device 100 according to the tenth embodiment, it is possible to prevent laser light leakage due to headlight breakage due to falling.

Note that it is preferable that the control for detecting the acceleration in the vertical direction can be set as necessary. For example, in wasteland, an acceleration in the vertical direction that is larger than a preset threshold value may be detected, but in that case, there is a high possibility that it is not an accident. Therefore, when traveling on rough land, it is possible to make it difficult to forcibly turn off the laser light source 1 by not performing control for detecting the acceleration in the vertical direction or by increasing the threshold value of the detected acceleration. Become.

In Examples 1 to 10 so far, the acceleration detection direction of the acceleration sensor has been described with respect to the front / rear / side / up / down (in other words, x, y, z) directions of the vehicle. An example in which the acceleration sensor detection axis is set in a direction inclined from the direction will be described.

(Example 11)
FIG. 31 is a diagram schematically illustrating configurations of the illumination device 100 and the automobile 200 according to the eleventh embodiment. For convenience of explanation, members having the same functions as those in the drawings described in the first to tenth embodiments are denoted by the same reference numerals and description thereof is omitted.

The headlamp unit 101 of the illumination device 100 according to the eleventh embodiment has the same structure as the headlamp unit 101 of the eighth embodiment as shown in FIG.

In this embodiment, as shown in FIG. 31, the detection axis direction of the acceleration sensor 3 is set in a direction inclined from the front-rear direction of the automobile 200.

For example, when the detection axis direction in the acceleration sensor 3 is set so that the detection axis is horizontal when the vehicle is arranged on a horizontal plane and is set to be inclined by 45 degrees from the vehicle front-rear direction, the detection sensitivity becomes the detection axis. Is reduced to “1 / √2” as compared with the case where the value is adjusted in the front-rear direction or the side direction.

Since the lighting control of the laser light source 1 according to the acceleration detected by the acceleration sensor is the same as in the previous embodiments, the description thereof is omitted.

(Action / Effect)
According to the illuminating device 100 which concerns on the present Example 11, the number of sensors can be reduced, and there exists an effect of leading to the low cost of a sensor system and a failure rate fall.

Here, if the sensitivity of the acceleration sensor 3 is sufficiently high, it is possible to obtain the same detection sensitivity as when the acceleration sensor is provided for each detection axis direction. Therefore, there are advantages that the number of sensors can be reduced and the cost can be reduced and the failure probability of the sensor can be reduced while maintaining the same detection sensitivity as when the acceleration sensor is provided for each detection axis direction.

(First threshold, second threshold)
(1) 1st threshold The 1st threshold is a threshold for light extinction preparation, that is, a threshold related to sudden braking and sudden steering. Examples of preferable numerical values are 0.2G or more, and the upper limit is 2G. The numerical value of 0.2 G as the lower limit value is an acceleration from the traveling of 60 km / h to the stop in about 8.5 seconds, which is a value close to the lower limit considered to be a sudden brake. Alternatively, 0.2 G is considered to be a deceleration acceleration based on a slightly stronger brake. Alternatively, 0.2 G is the centripetal acceleration when performing a circular motion with a radius of about 35 m at a speed of 30 km per hour. If a light extinguishing preparation operation (pulse drive) is performed at an acceleration slower than 0.2 G, a sensitive reaction can be caused. Therefore, it is preferable to set 0.2 G as the lower limit value.

The upper limit 2G corresponds to acceleration when a brake is applied to stop at 0.85 seconds from 60 km / h, or centripetal acceleration when rotating in a circle with a radius of 16.7 m at 60 km / h. This is because the acceleration in this case is also considered to be the upper limit of the acceleration of sudden operation for avoiding accidents that is normally considered or a value slightly exceeding it. If the safety side is considered, it is desirable that the first threshold value is low.

(1-1) Threshold value “1-1”
The threshold “1-1” relating to the rear-end collision mentioned in the eighth embodiment is preferably equal to or higher than the acceleration corresponding to the sudden braking. The concept of the first threshold and a numerical value can be used for this, and it is preferable to set the lower limit to 0.2 G and the upper limit to 2 G as the first threshold as absolute values. However, the actual set value is not necessarily the same as the first threshold value. For example, the first threshold value may be 0.2 G, and the threshold value “1-1” may be a negative direction threshold value corresponding to 0.3 G.

(2) Second Threshold The second threshold is a threshold for collision detection acceleration, and may be any acceleration equal to or higher than the first threshold, and is preferably at least 1G.

In addition to the so-called original automobile accident, this is also assumed, for example, when the vehicle starts moving at a low speed on a gentle slope and collides with an object such as a utility pole. That is, in the formula of momentum “f × t = m × v” (f: force of collision, t: time of collision, m: vehicle mass, v: vehicle speed)
m = 1000 kg, v = 5 km / h = 1.39 m / s
Assuming that, the time until this stops after decelerating at 1G acceleration is
t = 1.39 m / s ÷ 9.8 m / s ² = 0.142 seconds.

The force received until the vehicle stops is f = m × v ÷ t = 1000 kg × 1.39 m / s ÷ 0.142 seconds≈9789 N.

Since this is a force equivalent to about 1000 kgf, the destruction of the headlight is probably inevitable, and as an acceleration exceeding the acceleration when sudden braking is applied as the lower limit value and the threshold setting standard for turning off the light. Even in consideration of positioning, it is an appropriate value.

The upper limit value of the second threshold value is not particularly limited. However, if the sensor sensitivity of the acceleration sensor 3 is too sensitive and a malfunction in mounting becomes a problem, the second threshold value may be increased to about 10 G to several tens of G. Considering that the acceleration at the time of a collision accident and the operation acceleration of the airbag shown in non-patent literature are 10 G units, it is also appropriate to set the second threshold value to the value of 10 G units.

Here, preferable values of the upper limit value and the lower limit value of the first threshold value and the second threshold value will be described.

From the matters described on page 17 of Non-Patent Document 1 (“2008 Video Recording Drive Recorder Utilization Model Project Research Report”, pp. 23, March 2009, Ministry of Land, Infrastructure, Transport and Tourism, Japan) When acceleration of 0.2G or more in the front-rear direction and 0.3G or more in the lateral direction is detected, the driver generally recognizes that there was a possibility of a near-miss, that is, an accident. As mentioned above, it is preferable to set it to 0.2 G or more.

Also, page 381 of Non-Patent Document 2 ("Drive Recorder", Fujitsu Technical Report, July 2008 issue) shows an example of acceleration at the time of collision. The sudden braking acceleration from 20km / h is close to 1G. As described above, the upper limit value of the second threshold value is preferably about several tens of grams as described above.

Furthermore, page 2/4 of Non-Patent Document 3 ("Scientific analysis of drivers using video recording drive recorder: 2. Data collection by field test", JAMA MAGAZINE April 2005 issue, Japan Automobile Manufacturers Association) There is a graph that shows about 4-6 [m / s ² ] (0.4-0.6G) as a sudden brake at the time of rear-end collision and about 50 [m / s ² ] (5G) at the time of collision. As a reference, it is preferable to set the lower limit knowledge of the first threshold to 0.2G as a low value that covers at least 0.4G. Further, since the acceleration at the time of the collision is low and about 5G, it is preferable that the upper limit of the first threshold value for preparing for extinguishing is lower than this, so 2G is preferable as described above.

Conversely, the lower limit value of the collision detection acceleration and the second threshold value must be equal to or higher than the upper limit of the first threshold value for preparation for extinguishing the light (otherwise, if the one-inch brake is strong, it will be completely extinguished immediately).

On the other hand, as described in Non-Patent Document 2, the acceleration at the time of collision may be several tens of G, so the upper limit may be several tens of G.

The upper limit 2G of the first threshold value and the lower limit 1G of the second threshold value have overlapping numerical ranges, but at the time of designing, the pulse drive is first performed with a small acceleration and the large acceleration is extinguished. That is, it is not normally considered that the specific set value of the first threshold exceeds the set value of the second threshold. It should be noted that the above numerical range is a preferable value as a setting range.

(2-1) Threshold value “2-1”
The absolute value of the threshold value “2-1” regarding the rear-end collision mentioned in the eighth embodiment is desirably an acceleration corresponding to the rear-end collision or more. The concept of the second threshold and a numerical value can be used for this, and the lower limit of the absolute value is set to 1G and the upper limit of the absolute value is set to a value of 10G as in the second threshold. However, the actual setting value does not necessarily have the same absolute value as the second threshold value. For example, the second threshold value is set as the positive direction threshold value of the absolute value 2G, and the threshold value “2-1” is set as the negative direction threshold value corresponding to the absolute value 4G. It doesn't matter.

(Pulse drive frequency, peak value, duty)
(3) Pulse drive frequency The lower limit frequency of the pulse drive frequency is preferably about 50Hz × 2 = 100Hz, which is the frequency of flickering of non-inverter type fluorescent lamps in East Japan (so that flicker is not perceivable). preferable. This is consistent with the calculation of the non-lighting time at high speed running, which is listed as a numerical limitation of the minimum value of the temporary turn-off time in the description in Example 15 to be described later, and at high speed running (for example, 100 km / h). Even if it flashes (pulse drive) at 10 ms, which is the reciprocal of 100 Hz, the travel distance within that time is only 27 cm at the shortest, and visibility is not reduced so much even during sudden braking from high-speed driving. Of course, even if it is lower than this, for example, about 50 Hz, flicker is hardly perceived.

The upper limit frequency of the pulse drive frequency is not increased unnecessarily. Specifically, the upper limit of the switching speed in a normal power MOSFET is about 100 ns, and is the reciprocal of twice this time. It is preferable to set the upper limit to about 5 MHz. This upper limit value may be further increased when an element / circuit that consumes the least amount of power and can be used.

(4) Pulse driving peak value Even if the pulse driving peak value is equivalent to that of normal lighting, high power may be used as long as the laser is not damaged in order to maintain the average brightness as much as possible. A peak value corresponding to a large electric power is preferable as long as it is not damaged.

(5) Duty value for pulse drive (ON time ratio in one cycle)
As long as the duty value is not 0% (completely turned off) or 100% (completely turned on), any number can be used. However, the duty value may be 0% as a result. Specifically, when the acceleration exceeding the first threshold is detected and the laser is shifted to pulse driving, the acceleration exceeding the second threshold corresponding to the collision is detected at the first extinction timing, and the extinction is continued as it is. is there. Since such operations are within the scope of the present invention, they exist as exceptions and should be recognized. When the duty value is high, the decrease in the average light amount by pulse driving is reduced (if the same peak value), but the probability that the laser is turned off when an accident occurs subsequently decreases. Considering both, it may be selected or changed within the range of 50% ± 40%. Since the human pupil is also expanded when the surrounding environment is dark, it is one desirable setting / selection to reduce the duty and increase the probability of turning off the laser when an accident occurs.

(Maximum time to drive the laser and minimum time to drive the pulse when the second threshold is not detected after the first threshold is detected)
The time for which the laser is pulse-driven means a time during which sudden braking and sudden steering are continued and collision can be avoided. This corresponds to the maximum braking time when the “accelerated” brake with the lowest acceleration is depressed. If the acceleration falls below the first threshold within this time, it is assumed that an accident has been avoided and normal lighting is restored at that time. If it does not fall below the first threshold, pulse driving is continued.

Acceleration in the longitudinal direction If the maximum speed of the vehicle is Vmax and the minimum acceleration value that is regarded as a sudden brake is Gmin, the following equation is established for the acceleration in the longitudinal direction of the vehicle: Tmax = Vmax ÷ Gmin. The maximum drive time.

For example, if Vmax = 360km / h and the minimum value of sudden braking acceleration is 0.2G, Tmax = (360 × 10 ³ [m / h] ÷ 3600 [s / h]) ÷ (0.2 [G] × 9.8 [m / s ² /G])=51.2 [s].

The time when the vehicle is stopped at an acceleration that is the lower limit of the first threshold value described above from an extremely high-speed traveling state, which is 360 km / h, is the above value (51.2 [s]). However, since it is considered extremely rare to continue to perform a light brake operation that can be said to be the lower limit of sudden braking to avoid accidents for such a long time, the above figures are only the maximum time for pulse driving Of course, it does not matter if the pulse driving is finished in a shorter time than this, and the normal lighting (or extinguishing in the event of an accident) is shifted to.

Note that the minimum time for pulse driving is considered to be, for example, 0.85 seconds to 8.5 seconds. This is a value calculated with respect to the first threshold value of the aforementioned sudden braking, and is a numerical value considered as one of the appropriate ranges. However, as described in the tenth embodiment, when the vibration exceeding the first threshold value in the vertical direction is continued due to traveling on rough land, it is possible to switch from pulse driving to continuous driving. Absent. Further, the numerical value range may be out of the range, and for example, one cycle of pulse driving may be set as the minimum level. However, it is preferable that the turn-off when the second threshold is exceeded has priority over the above case and the turn-off is determined before the first turn-on of pulse driving.

Lateral acceleration The avoidance action by the sudden handle is usually until the vehicle body changes posture from several tens of degrees to 90 degrees at most, but it repeats the U-turn and makes one turn (360 degrees) to other vehicles that happen to pass by chance. Think about collisions. If the collision acceleration is not detected in this way, it may be considered that the vehicle is either successfully evading, running around the same place, or spinning and stopping.

The lateral acceleration that is judged as a sudden handle is 0.2G or more. The numerical value at the time of avoidance operation with a sudden handle is equivalent to 0.2G at a turning radius of 3.94m at 10km / h.

From now on, if Tr_max is the time it takes for the body to change its attitude 360 degrees, the radius of rotation is R, and the speed is Vr,
Tr_max = (2πR) ÷ Vr × (360 ° ÷ 360 °) = 2π × 3.94 [m] ÷ (10 × 10 ³ [m / h] ÷ 3600 [s / h]) × 1 = 8.91 [seconds]
It becomes.

[Embodiment 2]
Another embodiment of the present invention will be described as follows. Illumination apparatus 500 according to the present embodiment is used as a headlamp mounted on a vehicle such as an automobile. Moreover, since it has substantially the same configuration as the lighting device 100 described in the first embodiment, members having the same function are denoted by the same reference numerals, and detailed description thereof is omitted.

(Lighting device 500)
FIG. 32 is a schematic block diagram of lighting apparatus 500 according to the present embodiment.

As shown in FIG. 32, the illuminating device 500 includes a headlamp unit (light emitting unit) 501 that uses a semiconductor laser element (LD) as a light source, and laser driving for driving the LD of the headlamp unit 501. Circuit (driving circuit) 502.

The headlamp unit 501 has the same configuration as the headlamp unit 101 of the first embodiment. That is, the headlamp unit 501 includes a laser light source 1 composed of an LD, a light conversion unit 2 that converts laser light emitted from the laser light source 1 into visible light, and an acceleration sensor that detects acceleration of the headlamp unit 101. 3 is included.

The illumination device 500 according to the present embodiment is greatly different from the illumination device 100 of the first embodiment in that a housing 5 that covers the headlamp unit 501 is provided and the acceleration of the housing 5 is detected. Therefore, an acceleration sensor 6 is newly provided.

The acceleration sensor 6 transmits the detected acceleration signal to the laser drive circuit 502, like the acceleration sensor 3 provided in the headlamp unit 501.

The laser drive circuit 502 generates a laser drive current C0 corresponding to a laser control signal S0 from an illumination control unit (described later), and supplies the laser drive current C0 to the laser light source 1 of the headlamp unit 501.

The laser drive circuit 502 controls the supply of the laser drive current C0 to the laser light source 1 to the value of the acceleration signal from the acceleration sensor 3 (first acceleration sensor) and the acceleration sensor 6 (second acceleration sensor). It is designed to respond accordingly.

That is, the laser drive circuit 502 drives the laser light source 1 in accordance with the detection value by the acceleration sensor 6 in addition to the detection value by the acceleration sensor 3.

Specifically, the laser driving circuit 502 is configured such that the relative speed between the apparatus main body and the collision object is V, and the distance from the headlamp unit 501 (main part) to the casing 5 is X. When the acceleration sensor 6 as the second acceleration sensor provided in 5 detects acceleration exceeding the third threshold, the laser light source 1 is turned off for a time Y longer than (X ÷ V), and the laser When the acceleration sensor 3 detects an acceleration exceeding the fourth threshold while the light source 1 is turned off, the laser light source 1 is turned off for a time exceeding Y.

Details of the third threshold and the fourth threshold will be described later.

(Laser drive circuit 502)
FIG. 33 is a schematic block diagram of the laser drive circuit 502. As shown in FIG.

The laser drive circuit 502 includes a laser control unit 121, a laser drive unit 122, and an output switch element 123, as shown in FIG.

The laser control unit 121 and the laser driving unit 122 are supplied with acceleration signals S5 and S51 from the acceleration sensor 3 and the acceleration sensor 6. The acceleration signals S5 and S51 from the acceleration sensor 3 and the acceleration sensor 6 are given to at least one of the laser control unit 121 and the laser driving unit 122, and are signals for transmitting information on acceleration (impact etc.). Based on this information (acceleration magnitude), the laser control unit 121 or the laser driving unit 122 controls the laser light source 1 to be turned off.

Here, in order to perform the extinction control of the laser light source 1 based on the magnitude of the acceleration signal S51 from the acceleration sensor 6 provided in the casing 5, laser pulse driving (ON / OFF) is performed as preparation for extinction.

When the acceleration signal S51 is larger than a certain threshold (for example, a magnitude corresponding to an impact corresponding to a vehicle collision), the laser light source 1 can be irradiated with the laser light as fast as possible. In order to stop (turn off the light), it is preferable to directly determine the magnitude of the acceleration signal S51 by the laser driving unit 122.

In the laser drive unit 122 to be described later, an example is shown in which the magnitude of the acceleration signal S51 is directly determined to control the extinction.

The laser light source 1 includes a plurality of LD chips 11, and laser light is irradiated from each of the LD chips 11. Since the detailed description of the LD chip 11 has already been described in the first embodiment, the detailed description thereof is omitted here.

(Laser driver 122)
Next, details of the laser driving unit 122 will be described below with reference to FIGS. 34 and 35. FIG. 34 and 35 can be applied to the laser drive circuit 502 shown in FIG.

(Laser driver 122: step-down type)
FIG. 34 is a block diagram illustrating a circuit configuration of the step-down laser driving unit 122.

That is, FIG. 34 shows an example of a step-down circuit used when the voltage Vf necessary for driving the laser light source 1 is lower than the voltage Vb of the power source E (when the number of series of LD chips 11 is small). Yes.

As shown in FIG. 34, the step-down laser driver 122 includes a main switch element 1220, a coil 1221, a diode 1222, a capacitor 1223, a current detection resistor 1224, a differential amplifier 1225, a switching control unit 130, and an acceleration determination unit. 140 and the output switch element 123 described above. One end of the coil 1221 is connected to the power source E through the main switch element 1220. Note that another switch element may be provided between the power source E and the coil 1221.

During the period when the main switch element 1220 is ON, the current from the power source E is accumulated as magnetic flux energy through the coil 1221 and as electric charge in the capacitor 1223, and the current is also supplied to the laser light source 1. The current supplied to the laser light source 1 is detected by the current detection resistor 1224 and the differential amplifier 1225, and the main switch element 1220 is turned on / off so as to maintain the drive current value instructed from the laser controller 121.

34, the signal S6 is an output current signal, the signal S7 is an output voltage signal, and the signal S8 is a control signal for controlling switching of the main switch element 1220 between ON and OFF.

During the OFF period of the main switch element 1220, the magnetic flux energy of the coil 1221 is supplied to the laser light source 1 together with the capacitor 1223 through the diode 1222. The capacitor 1223 performs a smoothing operation that relaxes fluctuations in voltage (current) to the laser light source 1 by switching the main switch element 1220 between ON and OFF.

The acceleration determination unit 140 receives the acceleration signals S5 and S51 from the acceleration sensor 3 and the acceleration sensor 6, and generates signals S9, S91, and S11 as necessary based on the acceleration signals S5 and S51. The data is transmitted to the switching control unit 130. Details of the acceleration determination unit 140 will be described later.

Since the laser drive unit 122 includes the coil 1221 and the capacitor 1223 for storing energy as described above, even if the switching control unit 130 turns off the main switch element 1220, the current to the laser light source 1 is not turned off immediately. . For this reason, the output switch element 123 forcibly cuts off the current (at high speed).

(Laser driver 122: boost type)
FIG. 35 is a block diagram showing a circuit configuration of the boost type laser driver 122.

That is, in FIG. 35, when the voltage Vf necessary for driving the laser light source 1 is higher than the voltage Vb of the power source E (a plurality of LD chips 11 are somewhat in series (the number of series is 3 to 4 or more). ) Shows an example of a step-up circuit used for connection).

As shown in FIG. 35, the boost type laser driver 122 includes a main switch element 1220, a coil 1221, a diode 1222, a capacitor 1223, a current detection resistor 1224, a differential amplifier 1225, a switching control unit 130, and an acceleration determination unit. 140 and the output switch element 123 described above. One end of the coil 1221 is connected to the power source E. Note that another switch element may be provided between the power source E and the coil 1221.

Note that the signal S6 shown in FIG. 35 is an output current signal, the signal S7 is an output voltage signal, and the signal S8 is a control signal that controls switching of the main switch element 1220 between ON and OFF.

34 and 35 has the same configuration as the acceleration determination unit 140 shown in FIGS. 6 to 14 described in the first embodiment.

However, in the acceleration determination unit 140, the same circuit is provided so as to correspond to the acceleration sensor 3 and the acceleration sensor 6, respectively. In FIGS. 6 to 14, the signals generated from the signal S5 of the acceleration sensor 3 are S9 and S11, and the signal generated from the signal S51 of the acceleration sensor 6 provided on the housing is S9 replaced with S91. To do.

Although the case where the headlamp unit 101 is damaged due to the collision of the automobile described in the first embodiment is assumed, in this embodiment, the case where the headlamp unit 101 is damaged due to a stepping stone or the like is assumed. To explain.

Also in the present embodiment, it is determined based on the acceleration detected by the acceleration sensor that a stepping stone or the like has hit the headlamp unit 101.

Specific description will be given in Examples 12 to 15 below.

(Example 12)
FIG. 36 is a diagram schematically illustrating configurations of the lighting apparatus 100 and the automobile 200 according to the twelfth embodiment. For convenience of explanation, members having the same functions as those in the drawings described in Examples 1 to 11 of the first embodiment are denoted by the same reference numerals and description thereof is omitted.

As shown in FIG. 36, the headlamp unit 101 of the illumination device 100 according to the twelfth embodiment has substantially the same structure as the headlamp unit 101 of the eighth embodiment. However, the optical sensor 7 is provided in the housing 310. The difference is that a conductive detection member 315 is provided on the housing 310 side of the laser light cut filter 312.

Further, the illumination device 100 is provided with a cover (housing 5) that covers the headlamp unit 101 when considered as a headlight of an automobile. This cover is made of plastic, and the surface is coated with a conductive detection film. The cover is provided with an acceleration sensor 6 for detecting the collision of a collision object such as a stone with the cover. The output destination of the acceleration sensor 6 is a laser drive circuit 502.

That is, when the acceleration sensor 6 detects a large acceleration with a cover such as a stepping stone, the laser light source 1 is temporarily turned off by the laser driving circuit 502. The determination of the acceleration by the stepping stone or the like is performed based on the signal S91 generated by the acceleration determining unit 140 in accordance with the output S51 of the acceleration sensor 6 provided on the cover, that is, the housing 5.

Regarding the relighting of the laser light source 1, for example, the output from the acceleration sensor 6 has returned to a normal value (the acceleration sensor system is not damaged), the visible light emitting surface or the conductive film of the cover is abnormal (blocking = No damage), laser lighting test, normal voltage-to-current characteristics (confirmation that the laser is not damaged), and the light intensity signal obtained from the optical sensor 7 for the laser drive current At least one “self-diagnosis” such as being in a category that is detected (when the amount of light is detected even though the laser is not driven, etc., it is regarded as the entry of external light due to damage (= a state in which laser light can leak)) , And when it is determined that there is no problem with relighting.

Further, the laser drive circuit 502 performs drive control of the laser light source 1 according to the acceleration signal detected by the acceleration sensor 3.

For example, when the acceleration detected by the acceleration sensor 3 exceeds a first threshold value corresponding to sudden braking, sudden steering, etc. (when “lighting ready acceleration” is detected), the laser light source 1 is driven in pulses.

In addition, as shown in FIG. 36, when a car collides with the lighting device 100 of the host vehicle 200 by another vehicle 201 traveling in front while the vehicle 200 (hereinafter referred to as the host vehicle) that the driver drives is traveling. The stepping stone corresponding to the collision can be largely protected by a plastic cover. However, in consideration of the peculiarity of the laser light source 1, assuming that the stepping stone may break through the plastic cover and damage the main body, the acceleration detected by the acceleration sensor 6 installed on the cover causes the stepping stone to collide with the cover. Therefore, it is preferable to turn off the laser light source 1 when it corresponds to the acceleration generated.

It should be noted that the detection axis direction of acceleration detection at the cover is not limited to the front-rear direction, and may be the side surface direction or both.

(Action / Effect)
According to the illuminating device 100 according to the twelfth embodiment, it is possible to detect a risk factor (a stepping stone, a flying object, or a collision with another object of the own vehicle) of the main body with the cover, which is always provided for a normal headlight. So, if there is a danger that the main body will be destroyed and the laser beam will leak,
The laser is extinguished during the time until the risk factor reaches from the cover to the main body, so that the safety can be ensured or the safety can be further improved.

For example, if the vehicle speed (vs. stepping stone) is 360 km / h → 100 m / s, and the distance between the cover and the main body is 5 mm, the time required to penetrate the cover and reach the main body is 50 μs. Therefore, there is sufficient time for the electrical extinguishing operation. Until now, it has been described as a flying object at a speed of 360 km / h as an example of a collision of a stepping stone with a headlight, but it is not limited to a stepping stone but is a collision with a fixed object or is traveling at a speed of 180 km / h. It is obvious that the laser can be turned off in the same way in the case of a collision between vehicles.

(Example 13)
FIG. 37 is a diagram schematically illustrating the configuration of the illumination device 100 and the automobile 200 according to the thirteenth embodiment. For convenience of explanation, members having the same functions as those in the drawings explained in the first to twelfth embodiments are given the same reference numerals and explanation thereof is omitted.

The headlamp unit 101 of the illumination device 100 according to the thirteenth embodiment has substantially the same structure as the headlamp unit 101 of the twelfth embodiment, as shown in FIG.

In the thirteenth embodiment, a cover is provided and the acceleration sensor 6 is provided on the cover in the same manner as in the twelfth embodiment. However, when the acceleration detected by the acceleration sensor 6 exceeds the third threshold value, any object is formed on the cover. It is different in that it is judged that there is a danger of reaching the main body by colliding and damaging the cover.

The relative speed between the cover of the illumination device 100 and the stepping stone that is the collision object is V, the cover and the illumination device main body (the tip of the member or device that prevents laser light leakage or reduces it to a safe level, or the leading edge of the main body. Y ≧ (X ÷ V), where X is the distance from the portion of the lighting device 100 such as a part where the impact of optical member damage or misalignment cannot be denied if a large impact is applied somewhere. When only Y is turned off and acceleration exceeding the fourth threshold value, which means that the main body collides with an object, is detected during the turn-off period, the light is turned off for a time exceeding Y.

In addition, it is not necessary to be equal to the 4th threshold value detected with a collision with the main body of the illuminating device 100, and the 3rd threshold value detected with a cover.

(Action / Effect)
The operations and effects of the lighting apparatus 100 according to the thirteenth embodiment are substantially the same as those of the twelfth embodiment.

In other words, the normal headlight can always detect the risk factor for damage to the main body (stepping stones, flying objects, or collision with other objects of the vehicle) in advance, so that the main body is really destroyed and the laser light leaks. If there is a risk, the laser is turned off during the time until the risk factor reaches from the cover to the main body, and there is an effect that safety can be ensured or safety can be further improved.

For example, if the vehicle speed (vs. stepping stone) is 360 km / h → 100 m / s, and the distance between the cover and the main body is 5 mm, the time required to penetrate the cover and reach the main body is 50 μs. Therefore, there is sufficient time for the electrical extinguishing operation.

In Example 13, in addition to the above effects, the following effects are achieved.

In other words, if the collision is detected in advance by the cover, the light body (main part) will continue to turn off once the collision acceleration with the object is detected after the light is turned off by the previous detection. In this case, the laser beam leakage prevention probability and safety are improved.

(Example 14)
FIG. 38 is a diagram schematically illustrating configurations of the illumination device 100 and the automobile 200 according to the fourteenth embodiment. For convenience of explanation, members having the same functions as those in the drawings described in the first to thirteenth embodiments are denoted by the same reference numerals and description thereof is omitted.

The headlamp unit 101 of the illumination device 100 according to the thirteenth embodiment has substantially the same structure as the headlamp unit 101 of the thirteenth embodiment, as shown in FIG.

In the thirteenth embodiment, the relative speed between the cover of the illuminating device 100 and the stepping stone as the collision object is V, and the cover and the illuminating device main body (the tip of the member / device that prevents laser light leakage or reduces it to a safe level) Or, if a distance from the illumination device 100 main body such as the most advanced part of the main body is a part of the main body of the lighting apparatus 100 where the possibility of causing damage or displacement of the optical member cannot be denied, X is Y ≧ ( The light is extinguished for a time Y of (X ÷ V), and when acceleration exceeding the fourth threshold, which means a collision with an object, is detected during the extinguishing period, the extinguishing is continued for a time exceeding Y.

In this example, preferable X in the inequality will be described.

That is, the distance X of the inequality is preferably the shortest distance X1 between the main body (main part) housing and the cover, as shown in FIG. If the structure is flexible so that the impact is absorbed by the collision of that part and there is no risk of laser light leakage, even if it is destroyed, it will be "a part that may cause laser light leakage" For example, in FIG. 38, the distance X2 may be the distance X2 to the member (laser light cut filter 312) on the light emitting surface of the main body (main part).

(Action / Effect)
The operation / effect of the lighting apparatus 100 according to the fourteenth embodiment is the same as that of the thirteenth embodiment.

(Example 15)
FIG. 39 is a diagram schematically illustrating configurations of the illumination device 100 and the automobile 200 according to the fifteenth embodiment. For convenience of explanation, members having the same functions as those in the drawings explained in Examples 1 to 14 are given the same reference numerals and explanations thereof are omitted.

The headlamp unit 101 of the illumination device 100 according to the fourteenth embodiment has substantially the same structure as the headlamp unit 101 of the thirteenth embodiment, as shown in FIG.

In the present embodiment, the relationship between the temporary turn-off time of the laser light source 1 and the vehicle speed will be described.

That is, when the distance X of the above inequality is large and the speed V is low, the temporary turn-off time Y needs to be set long. However, if the time is left large, the time for traveling in the off state during high speed traveling becomes longer, which may reduce the safety.

For example, X = 100 mm, V = 5 km / h, and if it is temporarily turned off for safety against collision with a very slow stepping stone (flying object), Y ≧ 72 ms, but this time Y remains fixed When traveling at V = 360 km / h = 100 m / s, 7.2 m is unlit.

That is, a 72 ms idle running time, that is, a 7.2 m non-lighting running distance is newly generated until the driver of the automobile (vehicle) senses the danger and shifts to the braking operation. As described above, this time and distance are not necessarily negligible values.

Therefore, the vehicle speed signal is acquired from the outside, and the temporary turn-off time is adjusted according to the vehicle speed. For example, adjustment is made to shorten the temporary turn-off time as the speed increases.

For example, vehicle speed information is acquired from vehicle speed information detecting means 600 such as a tachometer and a speedometer as in the laser drive circuit 602 shown in FIG. 40, and the signal is sent to the laser drive circuit 602 as a vehicle speed signal in S12. For example, the time Y may be shortened so as to be approximately inversely proportional to the traveling speed.

(Action / Effect)
According to the illumination device 100 according to the fifteenth embodiment, since the time for temporarily turning off can be adjusted according to the vehicle speed, the time from the headlight cover damage to the main body damage is surely turned off and in the event of an accident. As well as ensuring the prevention of laser light leakage, the vehicle travel distance and time during extinguishing can be minimized, so that safety based on visibility can be secured.

(Relative speed, distance between cover and main body, temporary turn-off time)
The relationship between the relative speed, the distance between the cover and the main body, and the temporary turn-off time is shown by the following mathematical formula.

The headlamp state-of-the-art, that is, the relative speed between the cover and flying or colliding objects (including oncoming vehicles)
The distance between the part of the headlamp body (main part) that may leak laser light when impacted and the shortest part between the covers X
Y is the temporary turn-off time required when the acceleration sensor of the cover detects acceleration exceeding the third threshold.
When
If the relationship of Y ≧ (X ÷ V) is satisfied,
It can be turned off for more than the time it takes for the flying object and the object to be collided to hit the main body at the same speed without decelerating through the cover. This is to prevent the lighting during the previous time and to ensure safety, assuming that the main body is damaged as long as danger is detected by the cover.
(2) Limiting the numerical value of the shortest time and the longest value of the temporary extinguishing time First, since it is assumed that 1G collision≈5 km / h in the first embodiment, assuming that X = 100 mm and V = 5 km / h, Y = 72 ms. This time is assumed to be a time to feel flickering, but flickering itself is not a problem because it is only a moment when the impact is detected. If the turn-off time becomes shorter than this, since the flying object or the collision target breaks through the cover and the main body is damaged again, it is necessary to turn off the light temporarily at least for this time. On the other hand, in the case of high-speed traveling, this turn-off time is too long, so it is necessary to change the temporary turn-off time according to the vehicle speed as described above.

When traveling at a high speed with Y = 72 ms, for example, if V = 100 km / h, the vehicle travels 2 m.

In the case of higher speeds, for example, as described in Example 15, if V = 360 km / h, Y = 72 ms causes the vehicle to travel 7.2 m in a temporarily off state, which is an obstacle to accident avoidance. Therefore, it is desirable to obtain a traveling speed (vehicle speed) signal and adjust Y so that “Y = k × (X ÷ V) + ΔT”.

Note that the minimum value of Y is calculated according to the vehicle speed, for example, when X = 100 mm, which is the same as described above, the time until the flying object and the object to be collided break through the cover and collide with the main body should be extinguished. Then
When V = 360 [km / h]: 100 mm / 100 m / s = 1 ms
When V = 100 [km / h]: 100 mm ÷ 27.8 m / s = 3.6 ms
It is.

On the other hand, it is the longest value of Y, but this is constrained by the distance the vehicle travels while it is temporarily turned off.

The value of Y is arbitrary, but (a) 10 ms or less is desirable, and (b) 1 ms or less is desirable. With this, the no-light mileage during time Y is
When V = 360 [km / h]: 1m for (a), 10cm for (b)
When V = 100 [km / h]: 27cm for (a), 2.7cm for (b)
And all remain in an acceptable category.

Based on the above shortest and longest values, k and ΔT may be determined. k is a coefficient for arbitrarily setting the gradient of the relationship between the vehicle speed and the temporary turn-off time when the vehicle speed signal cannot be obtained at the speed itself, but only a few times or a fraction thereof. is there.
(3) Third threshold The third threshold is a threshold corresponding to the acceleration of the temporary extinction determination detected by the cover.

Basically, it may be equal to the second threshold value. That is, it may be 1G or more.
(4) Fourth Threshold The fourth threshold is a threshold corresponding to the extinction sustained acceleration detected by the main part (main body).

This may basically be the same as the second threshold value. That is, it may be 1G or more.

Note that the fourth threshold can be set smaller than the second threshold.

This is because the acceleration received by the main body is expected to be smaller than the acceleration received by the cover. The effect of this is more sensitive to the collision of an object that has enough momentum to destroy the body, although the momentum was scraped off by the cover, such as a stepping stone pierced the cover Can be detected.

In the present embodiment, the vehicle speed signal S12 from the vehicle speed information detecting means 600 is applied to the laser drive circuit 102, more specifically, the laser control unit 121 to calculate and correct the time Y. For example, as shown in FIG. 40, the vehicle speed signal S12 from the vehicle speed information detecting means 600 is given to the illumination control unit 103 as shown by the broken line in FIG. Then, it may be added from the illumination control unit 103 to the laser control unit 121 as the temporary turn-off time command signal Sy.

[Embodiment 3]
The following will describe still another embodiment of the present invention.

In addition, since the structure of the illuminating device 100 which concerns on this Embodiment is the same as that of the illuminating device 100 of the said Embodiment 2, detailed description is abbreviate | omitted.

In the present embodiment, in addition to the control by the acceleration signal by the acceleration sensor, the vehicle state is more reliably detected by using the braking signal and steering angle of the vehicle.

(Example 16)
FIG. 41 is a diagram schematically illustrating configurations of the illumination device 100 and the automobile 200 according to the sixteenth embodiment. For convenience of explanation, members having the same functions as those in the drawings explained in the first to fifteenth embodiments are given the same reference numerals and explanations thereof are omitted.

The headlamp unit 101 of the illumination device 100 according to the sixteenth embodiment has substantially the same structure as the headlamp unit 101 of the twelfth embodiment, as shown in FIG.

In the present embodiment, in addition to the light extinction preparation by the acceleration sensor in the previous embodiments, the light extinction preparation is performed with reference to the braking signal.

For example, as shown in FIG. 41, when the vehicle 200 on the frozen road surface 410 such as an ice burn is traveling, even if the driver rushes and steps on the brake suddenly, the vehicle slides on the road surface. Detection is difficult. Therefore, if the brake signal S13 indicating the degree of operation or control (or presence / absence) of the braking of the vehicle, such as the amount of depression of the brake pedal, is used to shift to the preparation for extinction (pulse drive), the

acceleration sensors

3 and 6 are turned on. The drive control of the laser light source 1 similar to the case where it is used can be performed.

∙ If the vehicle spins, etc., it is possible to detect the acceleration in the lateral direction (side direction) and prepare to turn off the lights, but the detection when sliding straight is indistinguishable from the straight running without any problem.

Therefore, the braking signal S13 is detected, and if it exceeds the fifth threshold, it is determined that the driver is in an uncontrollable or difficult state for vehicle sliding, and it is predicted that there is a risk of causing an accident. Move to preparation for turning off the laser.

The judgment is made by comparing the fifth threshold value with the brake pedal depression amount of the saddle that generates the fifth threshold brake acceleration on the normal road surface as a braking signal. Of course, there is no problem even if the

acceleration sensors

3 and 6 are used together with the conventional detection.

Note that braking is effective on a normal road surface, and acceleration corresponding to the braking can be detected. In this case, the braking signal may be used in a complementary manner. That is, priority is given to detection from the acceleration sensor, and if the acceleration signal corresponding to the braking operation cannot be detected from the acceleration sensor even though the braking signal is generated, the braking signal may be used as in this embodiment.

The fifth threshold value may be the first threshold value (equivalent to sudden braking) in the above embodiments. If the amount of depression is detected by the switch as a pedal displacement corresponding to the corresponding acceleration, the determination level of simple ON or OFF may be set as the fifth threshold value. Alternatively, the presence / absence of the ABS drive signal of the ABS-equipped vehicle may be used as the fifth threshold value of the braking signal. Normally, this may be diversion of the ON / OFF signal of the ABS control relay.

Further, when the laser light source 1 is pulse-driven and the detection value by the

acceleration sensors

3 and 6 exceeds the sixth threshold, the driving of the light source is stopped.

The sixth threshold value may be the second threshold value (equivalent to turning off) in the above embodiments.

(Action / Effect)
According to the illuminating device 100 according to the sixteenth embodiment, even when a sudden braking operation is performed like a frozen road surface, even when the detected acceleration is small due to sliding, it is possible to shift to preparation for turning off the laser. , Improve safety.

(Example 17)
FIG. 42 is a diagram schematically illustrating configurations of the illumination device 100 and the automobile 200 according to the seventeenth embodiment. For convenience of explanation, members having the same functions as those in the drawings described in the first to sixteenth embodiments are denoted by the same reference numerals and description thereof is omitted.

42. As shown in FIG. 42, the headlamp unit 101 of the lighting device 100 according to the seventeenth embodiment has substantially the same structure as the headlamp unit 101 of the twelfth embodiment.

In this embodiment, in addition to the light-off preparation by the acceleration sensor in the previous embodiments, the light-off preparation is performed with reference to the steering angle signal S14. That is, the vehicle speed and steering angle are observed, and if the lateral acceleration corresponding to the vehicle speed and steering angle is not detected, the vehicle is in an unexpected rotational state with the steering wheel turned off, or the steering wheel is Although the vehicle is turned off, the vehicle does not exhibit the steering characteristics desired by the driver, and it is determined that the vehicle is sliding in a substantially straight direction, and a light-off preparation operation is performed.

For example, as shown in FIG. 42, when the vehicle 200 on the frozen road surface 410 such as an ice burn is running, even if the driver rushes and steps on the brake suddenly, the vehicle slides on the road surface. Detection is difficult. Therefore, an acceleration calculation unit (not shown) determines the acceleration in the direction orthogonal to the traveling direction of the vehicle from the steering angle of the steering wheel and the vehicle speed signal, i.e., the vehicle itself is traveling on a normal road surface. The lateral (rotational) speed acceleration is calculated (which is expected to occur in some cases), and the corresponding acceleration is compared with the detection result of the lateral (side surface) acceleration sensor. Laser light source 1 similar to the case where

acceleration sensors

3 and 6 are used by shifting to preparation for extinction of light (pulse driving) if it deviates from acceleration (which is expected to occur when traveling on the road surface). Can be controlled.

Specifically, the turning radius can be calculated from the steering angle and the distance between the front and rear wheels of the vehicle. From the turning radius and the vehicle speed, the “heel” acceleration (centric acceleration) generated in the lateral direction can be calculated. If this deviates from the lateral acceleration sensor output by the seventh threshold or more, the process proceeds to the extinction preparation. On the other hand, the same processing may be performed for the case where acceleration equal to or greater than the seventh threshold value in the lateral direction is detected in a state where the steering angle is close to zero.

The seventh threshold value may be a first threshold value corresponding to a sudden handle.

In the state where the laser light source 1 is pulse-driven, when the detection value by the

acceleration sensors

3 and 6 exceeds the eighth threshold, the driving of the light source is stopped.

The eighth threshold value may be the second threshold value (corresponding to turning off) in the above embodiments.

Assuming the worst case in which the friction with the road surface is zero, the vehicle speed signal becomes zero by the braking operation, which means that the tire is locked. Can be switched to a light-off preparation operation. On the other hand, when an acceleration deviating from the value calculated from the vehicle speed / steering angle is detected, that is, when the vehicle falls into a spin state, the procedure described in the seventeenth embodiment may be used to shift to a turn-off preparation operation. .

(Action / Effect)
According to the illuminating device 100 according to the seventeenth embodiment, even when the vehicle is difficult to be controlled by operating the brake or the steering wheel as on a frozen road surface, it can be detected and the process can proceed to preparation for turning off the laser. , Improve safety.

(1) Fifth threshold value of braking signal The fifth threshold value expressed by acceleration, which is expected to occur when braking normally by the braking signal, is the same range as the first threshold value related to claim 1, that is, the lower limit. Is preferably 0.2G and the upper limit is 2G. This is because there is no great difference between the brake depression amount when it is desired to quickly stop the vehicle on the normal road surface and the brake amount which is depressed similarly on the frozen road surface.

If the brake ON / OFF or ABS operation signal is used, the fifth threshold value is not the acceleration, but the ABS operation signal (ie, the detection signal that the tire is slipping on the road surface while braking). Only ON / OFF may be used.

(2) Seventh Threshold at Steep Handle The seventh threshold is preferably 0.2G for the lower limit and 2G for the upper limit, as with the first threshold. This is because the above-mentioned centripetal acceleration can normally occur if the vehicle is being steered normally. If even that does not occur, the posture control such as spin is insufficient or impossible. This is because it can be assumed.

As for the numerical values, since the first threshold value and the second threshold value are calculated following Example 11, it is of course possible to obtain the same value and change each of the above threshold values.

In the third embodiment, as shown in FIG. 43, the braking signal S13 detected by the braking signal detection means (braking signal detection sensor) 700 and the steering angle signal S14 detected by the steering angle signal detection means 800 are used. A laser driving circuit 702 that inputs to the laser control unit 121 and performs laser driving control is used.

As the braking signal 13, as shown in FIG. 44, a change in the variable resistance value according to the depression amount of the brake pedal, a signal from a switch that is turned on or off when the brake pedal is depressed by a certain amount, or an ABS operation signal is used. Use. That is, the braking signal detection unit 700 detects these signals and sends them to the laser control unit 121 as a braking signal S13.

Further, as the steering angle signal S14, a signal from a steering angle sensor (variable resistance, torsion sensor, rotary encoder, etc.) that detects an angle when the steering wheel (steering) is turned, that is, a steering angle is used. That is, the steering angle signal detection means 800 detects this signal and sends it to the laser controller 121 as the steering angle signal S14.

As described above, an embodiment of the present invention can be expressed as follows.

In other words, the drive circuit may stop driving the light source when the value detected by the acceleration sensor exceeds a second threshold value greater than the first threshold value while the light source is pulse-driven. preferable.

According to the above configuration, the driving circuit stops driving the light source when the detection value by the acceleration sensor exceeds the second threshold value that is larger than the first threshold value while the light source is pulse-driven. As a result, it is possible to reliably eliminate leakage of laser light due to damage to the light emitting portion.

Here, when the lighting device having the above configuration is mounted on a vehicle as a headlamp, the first threshold value is a value corresponding to an acceleration when the vehicle suddenly brakes or an acceleration corresponding to when the vehicle suddenly turns off. It is preferable to set the value of. Preferably, the second threshold value is an acceleration value that occurs when the vehicle collides with another vehicle or the like, more precisely, a value corresponding to an acceleration value that may cause the headlight to break down and leak laser light. Good to do.

It is preferable that the drive circuit drives the light source with a pulse whose off period is longer than the on period when the light source is pulse-driven for a certain period of time.

In this case, since the light source is driven with a pulse whose off period is longer than the on period, the laser beam irradiation is already stopped when the laser beam irradiation is stopped from the semiconductor laser element. The probability of encountering a case can be increased.

Therefore, the probability of avoiding secondary disasters due to leakage of laser light can be increased.

The driving circuit preferably drives the light source with a laser power larger than the laser power before the pulse driving when the light source is pulse-driven for a certain time.

In this case, the brightness of the laser beam during pulse driving can be maintained.

When the acceleration sensor is a first acceleration sensor provided in a main part including the light emitting unit, a second acceleration sensor that detects acceleration of the case is provided in a case that covers the main part, It is preferable that the drive circuit drives the light source according to a detection value by the second acceleration sensor in addition to a detection value by the first acceleration sensor.

According to the above configuration, the acceleration is detected not only by the first acceleration sensor provided in the main part including the light emitting part, but also by the second acceleration sensor that detects the acceleration of the casing on the casing covering the main part. As a result, the range of acceleration detection by the acceleration sensor can be expanded.

That is, since the acceleration that could not be detected by one of the acceleration sensors can be detected by the other acceleration sensor, the range of acceleration detection can be expanded.

As a result, it is possible to take measures assuming various causes of damage to the light emitting part, and thus it is possible to reliably reduce the leakage of laser light due to damage to the light emitting part.

When the relative speed between the apparatus main body and the collision object is V and the distance from the main part to the case is X, the second acceleration sensor provided in the case exceeds the third threshold. When acceleration is detected, the light source is turned off for a time Y longer than (X ÷ V), and while the light source is turned off, the first acceleration sensor detects an acceleration exceeding a fourth threshold. When detected, it is preferable to turn off the light source for a time exceeding Y.

Here, a preferable value of the third threshold value is an acceleration with which there is a possibility that a collision object that has collided with the casing penetrates, or that the casing is damaged even if the collision object does not penetrate.

If the upper limit of the third threshold is determined as described above, it is possible to ensure safety when it is assumed that the collision object that collides with the housing reaches the main part and the main part is damaged. This is because when the second acceleration sensor provided in the housing detects an acceleration exceeding the third threshold, the light source is turned off for a time Y longer than (X ÷ V), thereby colliding with the housing. This is because the semiconductor laser element is in the extinguished state until the colliding object penetrating through reaches the main part including the light source. Even if the case did not break, or even if the case was damaged, the main part was not damaged, the light source was turned off for the time corresponding to the arrival of the collision object from the case to the main part. As a result, safety against laser light leakage is ensured.

In addition, when the first acceleration sensor detects acceleration exceeding the fourth threshold while the light source is turned off, the light source is turned off for a time exceeding the Y. Even if the impact object penetrating the housing reaches the light emitting part and the main part is damaged, the light source is already turned off in the light emitting part. Therefore, laser light leakage due to breakage of the main part can be reliably eliminated.

The above lighting devices may be used as headlamps mounted on the vehicle.

Specific headlamps are shown below.

The illumination device further includes an acceleration sensor that detects an acceleration of the illumination device, and the drive circuit is in a state where the light source is pulse-driven and a detection value by the acceleration sensor exceeds a sixth threshold value, It is preferable to stop driving the light source.

As a result, the light source is turned off when an impact is detected by the acceleration sensor while the braking signal is detected and the light source is pulse-driven, so that leakage of the laser beam due to damage to the illumination device is minimized. Can do.

It is preferable that the driving circuit stops driving the light source when a value detected by the acceleration sensor exceeds an eighth threshold value while the light source is pulse-driven.

As a result, the light source is turned off when an impact is detected by the acceleration sensor while the braking signal is detected and the light source is pulse-driven, so that the leakage of the laser beam due to the damage of the light emitting part can be stopped accurately. Can do.

In this case, it is more preferable that the acceleration sensor detects acceleration in the longitudinal direction and lateral direction of the vehicle. In this way, the collision between the vehicle and the collision object can be detected regardless of the posture of the vehicle (spin or simple sliding), and the light source can be turned off immediately.

In addition, a vehicle including the headlight is also included in the technical scope of the present invention.

The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope shown in the claims, and embodiments obtained by appropriately combining technical means disclosed in different embodiments. Is also included in the technical scope of the present invention.

The present invention can be applied to lighting devices, headlamps, and vehicles equipped with the headlamps. Further, the lighting device (or headlamp) can be applied not only to the vehicle headlamp but also to other lighting devices (or headlamps). An example of the other illumination device (or headlamp) is a downlight. A downlight is a lighting device installed on the ceiling of a structure such as a house or a vehicle. In addition, the lighting device (or headlamp) of the present invention may be realized as a headlamp of a moving object other than a vehicle (for example, a human, a ship, an aircraft, a submersible, a rocket, etc.) You may implement | achieve as interior lighting fixtures (a stand lamp etc.) other than a searchlight, a projector, and a downlight.

DESCRIPTION OF SYMBOLS 1 Laser light source 2 Light conversion part 3 Acceleration sensor 4 Condensing lens 5 Case 6 Acceleration sensor 7 Optical sensor 10 Head lamp 11 LD chip 17 Anode electrode 18 Substrate 19 Cathode electrode 100 Illuminating device 101 Head lamp part 102 Laser drive circuit 103 Illumination Control unit 111 Active layer 112 Clad layer 113 Clad layer 114 Open surface 115 Open surface 116 Light emitting point 121 Laser control unit 122 Laser drive unit 1220 Main switch element 1221 Coil 1222 Diode 1223 Capacitor 1224 Current detection resistor 1225 Differential amplifier 123 Output switch Element 130 Switching control unit 140 Acceleration determination unit 1401 Amplifier 1402 Amplifier 1403 Comparator 1404 Resistor 1405 Capacitor 1406 Comparator 1407 Resistor 1408 Comparator 1 DESCRIPTION OF SYMBOLS 10 Resistance 1411 Resistance 200 Automobile 201 Other vehicle 300 Case 300a Inner surface 301 Phosphor 302 Laser light cut filter 303 Phosphor holding member 304 Shading process part 305 Optical fiber 306 Polarization filter 310 Case 310a Inner surface 311 Phosphor 312 Laser light cut filter 313 Side surface direction 314 Vertical direction 315 Conductivity detection member 400 Road 400a Step 410 Frozen road surface 500 Illumination device 501 Headlamp unit 502 Laser drive circuit 600 Vehicle speed information detection means 602 Laser drive circuit 700 Braking signal detection means (braking signal detection sensor)
702 Laser drive circuit 800 Steering angle signal detection means AMP Amplifier C0 Laser drive current E Power supply L0 Laser light L1 Illumination light S0 Laser control signal S5 Acceleration signal V Speed X Distance X1 Shortest distance X2 Distance Y Temporary turn-off time

Claims

A light emitting unit using a laser as a light source;
A drive circuit for driving the light source;
An acceleration sensor for detecting the acceleration of the light emitting unit,
The drive circuit is
While driving the light source,
An illumination device, wherein when the value detected by the acceleration sensor exceeds a first threshold, the light source is pulse-driven for a predetermined time.
The drive circuit is
With the light source being pulse driven,
2. The lighting device according to claim 1, wherein the driving of the light source is stopped when a value detected by the acceleration sensor exceeds a second threshold value that is larger than the first threshold value.
The drive circuit is
When the above light source is pulse driven for a certain time,
The lighting device according to claim 1, wherein the light source is driven by a pulse whose off period is longer than the on period.
The drive circuit is
When the above light source is pulsed for a certain time,
The illumination device according to claim 1, wherein the light source is driven with a laser power larger than a laser power before pulse driving.
When the acceleration sensor is a first acceleration sensor provided in a main part including the light emitting unit,
A housing that covers the main part is provided with a second acceleration sensor that detects acceleration of the housing,
The drive circuit is
The lighting device according to claim 1, wherein the light source is driven in accordance with a detection value obtained by the second acceleration sensor in addition to a detection value obtained by the first acceleration sensor.
The drive circuit is
The relative speed between the main body and the collision object is V
When the distance from the main part to the housing is X,
When the second acceleration sensor provided in the housing detects an acceleration exceeding the third threshold,
The light source is turned off for a time Y longer than (X ÷ V),
The light source is turned off for a time exceeding the Y when the first acceleration sensor detects an acceleration exceeding a fourth threshold while the light source is turned off. Lighting device.
A headlamp comprising the lighting device according to any one of claims 1 to 6.
A lighting device provided in a vehicle, having a light emitting unit using a laser as a light source, and a drive circuit for driving the light source;
A braking signal detection sensor for detecting the braking signal of the vehicle,
The drive circuit is
While driving the light source,
A headlamp, wherein the light source is pulse-driven for a certain period of time when a value detected by the braking signal detection sensor exceeds a fifth threshold value.
An acceleration sensor for detecting the acceleration of the lighting device;
The drive circuit is
In the state where the light source is pulse-driven,
The headlamp according to claim 8, wherein when the value detected by the acceleration sensor exceeds a sixth threshold value, driving of the light source is stopped.
A lighting device provided in a vehicle, having a light emitting unit using a laser as a light source, and a drive circuit for driving the light source;
An acceleration sensor for detecting the acceleration of the lighting device;
An acceleration calculating unit that calculates acceleration in a direction orthogonal to the traveling direction of the vehicle from a speed signal indicating the speed of the vehicle and a steering angle signal indicating the steering angle of the vehicle;
The drive circuit is
A headlight characterized in that when the absolute value of the difference between the acceleration calculated by the acceleration calculation unit and the acceleration detected by the acceleration sensor exceeds a seventh threshold value, the light source is pulse-driven for a predetermined time. light.
The drive circuit is
With the light source being pulse driven,
The headlamp according to claim 10, wherein when the value detected by the acceleration sensor exceeds an eighth threshold, the driving of the light source is stopped.
A vehicle comprising the headlamp according to any one of claims 7 to 11.