United States Patent [19J
`Gotoh
`
`[54] HEAD LAMP DEVICE FOR VEHICLE
`
`[75]
`
`Inventor: Shinichiro Gotoh, Wako, Japan
`
`[73] Assignee: Honda Giken Kogyo Kabushiki
`Kaisha, Tokyo, Japan
`
`[21] Appl. No.: 08/858,361
`
`[22] Filed:
`
`May 19, 1997
`
`[30]
`
`Foreign Application Priority Data
`
`May 20, 1996
`
`[JP]
`
`Japan .................................... 8-124186
`
`Int. Cl.6
`....................................................... B60Q 1/08
`[51]
`[52] U.S. Cl. ........................... 362/466; 362/272; 362/276
`[58] Field of Search ..................................... 340/466, 467,
`340/575, 576; 362/37, 43, 464, 465, 466,
`276, 802, 271, 272
`
`[56]
`
`References Cited
`
`U.S. PATENT DOCUMENTS
`
`8/1986 Seko et a!. .............................. 340/576
`4,604,611
`8/1989 Oikawa ................................... 362/466
`4,858,080
`5,060,120 10/1991 Kobayashi et a!. ..................... 362/465
`8/1992 Kobayashi et a!. ..................... 362/466
`5,138,540
`5,453,929
`9/1995 Stove ...................................... 340/575
`
`111111
`
`1111111111111111111111111111111111111111111111111111111111111
`US005931572A
`[11] Patent Number:
`[45] Date of Patent:
`
`5,931,572
`Aug. 3, 1999
`
`........................ 362/466
`3/1996 Cochard et a!.
`5,499,168
`5,588,733 12/1996 Gotou ........................................ 362/37
`8/1997 Mori et a!. .............................. 362/466
`5,660,454
`
`FOREIGN PATENT DOCUMENTS
`
`62-77249
`314742
`
`4/1987
`1!1991
`
`Japan .
`Japan .
`
`Primary Examiner-Alan Cariaso
`Attorney, Agent, or Firm-Carrier, Blackman & Associates,
`P.C.; Joseph P. Carrier; William D. Blackman
`[57]
`
`ABSTRACT
`
`A head lamp device for a vehicle capable of changing a
`lighting region in front of the vehicle in rightward and
`leftward directions is provided. The device comprises a head
`lamp, lighting region changing means for changing the
`lighting region of the head lamp, strain degree detecting
`means for detecting degree of strain of the driver, and
`control means for controlling the lighting region changing
`means on the basis of information detected by the strain
`degree detecting means. The control means adjusts the
`amount and/or the speed of change of the lighting region in
`accordance with degree of strain of the driver. The change of
`the lighting region can be carried out naturally without sense
`of incongruity in view of degree of strain of the driver.
`
`15 Claims, 6 Drawing Sheets
`
`11)
`
`CCD
`CAMERA
`
`PICTURE
`~ PROCESSING
`APPARATUS
`
`13
`'--
`
`STEERING
`ANGLE
`SENSOR
`
`19
`'--
`
`SPEED
`SENSOR
`
`TURNING MOVE-
`MENT SENSOR
`
`20
`....../
`
`12)
`
`Ve
`
`,
`
`$
`
`...
`
`(14
`
`DISTRIBUTION H MOTOR -
`DRIVER
`~
`10
`
`LIGHT
`
`CONTROL
`ECU
`
`I
`
`'
`
`I' '
`
`(8
`~ LEFT MOTOR I
`
`~ RIGHT MOTOR I
`'-s
`
`16
`HEART RATE _/
`HEART
`15
`' - RATE H PROCESSING
`APPARATUS
`SENSOR
`
`SKIN POTENTIAL J
`ELECTRIC SKIN
`POTENTIAL ~ PROCESSING
`SENSOR
`APPARATUS
`7.)
`
`,.,........
`21
`
`MAP INFORMATION
`OUTPUTTING MEANS
`
`18
`
`122
`PRESENT POSITION
`DETECTING MEANS
`
`...
`,
`
`Page 1 of 12
`
`

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`U.S. Patent
`
`Aug. 3,1999
`
`Sheet 1 of 6
`
`5,931,572
`
`L L
`
`3
`
`1---
`
`FIG. 1
`
`10
`
`7
`
`FIG. 2
`
`Page 2 of 12
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`

`
`U.S. Patent
`
`Aug. 3, 1999
`
`Sheet 2 of 6
`
`5,931,572
`
`-9
`
`<
`
`>
`
`FIG. 3
`
`Page 3 of 12
`
`

`
`FIG. 4
`
`d
`•
`\Jl
`•
`
`19
`SPEED
`' - SENSOR
`
`12)
`
`11)
`ceo
`CAMERA
`
`PICTURE
`H PROCESSING
`APPARATUS
`
`13
`'--
`
`STEERING
`ANGLE
`SENSOR
`
`20
`TURNING MOVE-
`MENT SENSOR l-/
`,,
`
`Ve
`
`...
`,
`
`$
`
`..
`,
`
`~It
`
`LIGHT
`DISTRIBUTION
`CONTROL
`ECU
`
`J[\
`
`[\ J [\
`
`I 1\
`
`(14
`
`(8
`rl LEFT MOTOR I
`8
`~MOTOR~
`' DRIVER
`Y[ RIGHT MOTOR I
`~
`,_- 8
`10
`
`HEART RATE v
`HEART
`15
`'- RATE H PROCESSING
`APPARATUS
`SENSOR
`
`16
`
`18 v
`
`SKIN POTENTIAL
`PROCESSING
`APPARATUS
`
`ELECTRIC SKIN
`POTENTIAL H
`SENSOR
`17 .J
`
`,-
`21
`
`MAP INFORMATION
`OUTPUTTING MEANS
`
`122
`PRESENT POSITION
`DETECTING MEANS
`
`...
`
`Page 4 of 12
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`

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`U.S. Patent
`
`Aug. 3,1999
`
`Sheet 4 of 6
`
`5,931,572
`
`START
`
`51
`
`52
`
`TARGET CONTROL ANGLE 8 1
`DEC IDEO FROM ¢ - 8 1 MAP
`
`OPTIMUM CONTROL SPEED K
`DECIDED FROM Ve-K MAP
`
`e 1 > eo
`
`N
`
`N
`
`55
`
`56
`
`57
`
`o = e 1
`
`RETURN
`
`FIG. 5
`
`Page 5 of 12
`
`

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`U.S. Patent
`
`Aug. 3,1999
`
`Sheet 5 of 6
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`5,931,572
`
`~
`
`0 cr::. 1--
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`::z:<D
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`:EV')
`b:
`0
`
`0 EYE MOVING SPEED Ve
`
`FIG. 7
`
`Page 6 of 12
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`

`
`U.S. Patent
`
`Aug. 3, 1999
`
`Sheet 6 of 6
`
`5,931,572
`
`-e-
`UJ
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`
`Page 7 of 12
`
`

`
`5,931,572
`
`1
`HEAD LAMP DEVICE FOR VEHICLE
`
`BACKGROUND OF THE INVENTION
`
`The present invention relates to light distribution control
`of a head lamp of a vehicle for changing a lighting region
`produced by the head lamp toward right and left direction.
`
`DESCRIPTION OF RELEVANT ART
`
`2
`The strain degree detecting means may detect degree of
`strain of the driver by analyzing movement of the eye(s) of
`the driver. Namely, when the eye of the driver moves
`violently or rapidly it is judged that the degree of strain is
`5 high and when the eye moves slowly, it is judged that the
`degree of strain is low.
`The strain degree detecting means may also detect degree
`of strain of the driver by analyzing the heart rate or skin
`electric potential of the driver. Generally, when the heart rate
`10 is high or the skin electric potential is low, the degree of
`strain can be judged high, and when the heart rate is low or
`the skin electric potential is high, the degree of strain can be
`judged low.
`The present invention provides also a head lamp device
`for a vehicle capable of changing a lighting region in front
`of the vehicle in rightward and leftward directions, com(cid:173)
`prising lighting region changing means for changing the
`lighting region of the head lamp; operation state detecting
`means for detecting an operation state of the vehicle; strain
`degree judging means for judging a degree of strain of the
`driven by analyzing information detected by the operation
`state detecting means; and control means for controlling the
`lighting region changing means base on of information
`judged by the strain degree judging means and adjusting at
`least one of amount of change and speed of change of the
`lighting region in accordance with the judged degree of
`strain of the driver.
`Since the strain degree judging means judges the degree
`of strain of the driver by analyzing information detected by
`the operation state detecting means and the control means
`changes the lighting region on the basis of the degree of
`strain, the lighting region can be changed in accordance with
`the degree of strain of the driver.
`The operation state detecting means may be a vehicle
`speed sensor for detecting vehicle speed and the strain
`degree judging means may judge the degree of strain of the
`driver by analyzing the vehicle speed detected by the vehicle
`speed sensor. When speed or acceleration of the vehicle is
`high or low, the degree of strain can be judged respectively
`high or low. Thus a change of the lighting region in
`accordance with the degree of strain is possible.
`The operation state detecting means may also be a steer(cid:173)
`ing angle sensor for detecting a steering angle and/or steer-
`45 ing speed of the vehicle and the strain degree judging means
`may judge the degree of strain of the driver by analyzing the
`steering angle and/or steering speed detected by the steering
`angle sensor. When the steering angle speed is high or low,
`the degree of strain can be judged respectively high or low.
`50 Thus a change of the lighting region in accordance with the
`degree of strain of the driver is possible.
`The operation state detecting means may also be a turning
`movement sensor for detecting turning movement of the
`vehicle body, and the strain degree judging means may judge
`the degree of strain of the driver by analyzing the turning
`movement detected by the turning movement sensor. When
`lateral acceleration or yaw rate of the vehicle body is large,
`the degree of strain can be judged to be high, and when the
`lateral acceleration or yaw rate is small, the degree of strain
`can be judged to be low. Thus a change of the lighting region
`in accordance with degree of strain is possible.
`The present invention provides further a head lamp device
`for a vehicle capable of changing a lighting region in front
`of the vehicle in rightward and leftward directions, com(cid:173)
`prising lighting region changing means for changing the
`lighting region of the head lamp; map information output(cid:173)
`ting means for outputting map information representing a
`
`Hitherto, various devices for changing a lighting region of
`a vehicles head lamp right and left have been proposed.
`Almost all of the devices change the lighting region in
`accordance with a steering angle of a steering wheel
`(Japanese laid-open patent publications No. Sho 62-77249,
`No. Hei 3-14742 etc.). According to the devices, the lighting
`region of the head lamp is changed toward a direction of 15
`steering to increase lighting of the direction in which a
`vehicle is just going to advance.
`In the Japanese laid-open patent publication No. Hei
`3-14742, pertinent lighting angles corresponding to steering
`angles are determined beforehand and stored as a map, and 20
`controls for changing the lighting region are carried out on
`the basis of the map.
`However, in the above-mentioned prior arts, no condition
`of the driver himself is taken into consideration. Therefore, 25
`when the driver is strained because of the state of a road in
`front or the state of operation of the vehicle, he may feel
`sometimes that a change of the lighting region occurs too
`slowly, or when a degree of the strain is low conversely, he
`may feel sometimes that a change of the lighting region is 30
`fast and troublesome.
`Namely, when the driver is strained, a moving speed of his
`eye is fast, so that even if a change of the lighting region is
`carried out large and fast correspondingly, there is no sense
`of incongruity or rather it desirably meets the driver's sense 35
`and intention. On the other hand, when the degree of the
`drivers strain is low, movement of his eye are few and slow,
`so that even if a change of lighting region is slight, it can be
`perceived sensitively and, therefore, if the change of lighting
`region is large or fast, the driver has a sense of incongruity 40
`and feels troublesome.
`
`SUMMARY OF THE INVENTION
`The present invention has been accomplished in view of
`the foregoing and it is an object of the present invention to
`provide a head lamp device for a vehicle in which change of
`the lighting region can be carried out naturally without any
`sense of incongruity in view of a degree of strain of the
`driver.
`In order to accomplish the aforesaid object, the present
`invention provides a head lamp device for a vehicle capable
`of changing a lighting region in front of the vehicle in
`rightward and leftward directions. The device comprises a
`head lamp lighting region changing means for changing the
`lighting region of the head lamp; strain degree detecting 55
`means for detecting a degree of strain of a driver; and control
`means for controlling the lighting region changing means
`base on information detected by the strain degree detecting
`means, and the control means adjusts at least one of amount
`of change and speed of change of the lighting region in 60
`accordance with the detected degree of strain of the driver.
`Since at least one of amount of change and speed of
`change of the lighting region is adjusted in accordance with
`the degree of strain of the driver, a pertinent change of the
`lighting region which does not give the driver a sense of 65
`incongruity and meets the driver's sense and intention is
`possible.
`
`Page 8 of 12
`
`

`
`5,931,572
`
`5
`
`3
`map; present position detecting means for detecting a
`present position of a proper vehicle on the map; strain degree
`judging means for judging a degree of strain of the driver
`base on the map information outputted by the map infor(cid:173)
`mation outputting means and the present position of the
`proper vehicle detected by the present position detecting
`means; and control means for controlling the lighting region
`changing means base on information on the degree of driver
`strain judged by the strain degree judging means and adjust(cid:173)
`ing at least one of amount of change and speed of change of
`the lighting region in accordance with the degree of strain of
`the driver judged from a state of road in front of the proper
`vehicle.
`From a state of the road on which the proper vehicle is
`running, the degree of strain of the driver who is watching
`the state can be judged. Thus a change of the lighting region
`in accordance with the degree of strain is possible.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`
`4
`shaft of a motor 8 is engaged with a worm wheel 6 fitted to
`the rotary shaft 5.
`Accordingly, the lamp 4 is swung together with the rotary
`shaft 5 through an engagement between the worm gear 7 and
`the worm wheel 6 under a driving force of the motor 8. The
`motor 8 is controlled for its driving action by a light
`distributing control ECU 10.
`The vehicle 1 has a CCD camera 11 (FIG. 4) arranged in
`the vicinity of an upper end or lower end of a front window
`10 in front of a driver's seat (for example on an instrument
`panel) to take a picture of driver's face, particularly his eye.
`FIG. 3 shows a picture taken by the CCD camera 11. This
`picture information is inputted into a picture processing
`apparatus 12 which processes the picture, analyzes move-
`15 ment of the driver's eye, particularly the eyeball thereof, to
`calculate a moving speed of the eye and outputs a result of
`the calculation to the light distribution control ECU 10. The
`eye moving speed Ve is used as a measure of degree of strain
`of the driver and if the eye moving speed is faster, the degree
`20 of strain of the driver is judged higher correspondingly.
`FIG. 4 is a rough block diagram of a control system
`according to the present embodiment controlled by the light
`distribution control ECU 10. Into the light distribution
`control ECU 10 is inputted a detected steering angle <P from
`25 a steering angle sensor 13 for detecting a steering angle of
`a steering wheel, as well as the eye moving speed Ve from
`the picture processing apparatus 12.
`The light distribution control ECU 10 finally decides a
`required amount of change of the lighting region, that is a
`lighting angle 8, on the basis of the eye moving speed Ve and
`the steering angle <jl, and outputs a control signal to the motor
`driver 14 for realizing the lighting angle 8. The motor driver
`14 drives and controls the right and left motors 8, 8.
`A procedure of lighting region control according to the
`35 above-mentioned control system will be described with
`reference to a flow chart of FIG. 5.
`At first, a target control angle 81 is decided from a steering
`angle <P based on a <jl-8 1 map as indicated in step 1.
`In the <jl-8 1 map, a target control angle 81 which is a
`lighting angle to be aimed is set in regard to a steering angle
`<P beforehand, and FIG. 6 is a coordinate expression thereof.
`A non-responsive zone in which the target control angle 81
`is not changed is provided at a range where the steering
`45 angle <P is small. Except for the non-responsive zone, the
`target control angle 81 increases or decreases in proportion
`to the steering angle <jl, generally, but is kept constant if the
`steering angle <P rises above a limit in either direction.
`After the target control angle 81 is decided from the
`50 steering angle <P based on the <jl-8 1 map, the flow advances
`to Step 2 for deciding an optimum control speed K from the
`eye moving speed Ve based on a Ve-K map. In the Ve-K
`map, an optimum control speed K of the lighting angle is set
`in regard to an eye moving speed Ve, and FIG. 7 is a
`55 coordinate expression thereof.
`The optimum control speed K is proportional to the eye
`moving speed Ve and as the eye moving speed Ve increases,
`the optimum control speed K also increases. However, if the
`eye moving speed Ve rises above a limit, the optimum speed
`60 K is kept constant
`After the target control angle 81 and the optimum control
`speed K are decided, the flow advances to Step 3 for
`comparing a target control speed 181 -8 01/d with the optimum
`control speed K. 80 is the lighting angle at present and d is
`65 a processing time for 1 cycle of this control routine.
`Therefore, the target control speed 18 1-80 1/d means a rate
`of change of the lighting angle required for changing the
`
`FIG. 1 is a view showing a vehicle having a head lamp
`device of one preferred embodiment of the present invention
`as viewed from above;
`FIG. 2 is a schematic perspective view showing a swing(cid:173)
`ing mechanism for a head lamp of the preferred embodiment
`of FIG. 1;
`FIG. 3 is a view showing a picture taken by a CCD
`camera;
`FIG. 4 is a rough block diagram of a control system;
`FIG. 5 is a flow chart showing a procedure for changing 30
`the light region;
`FIG. 6 is a coordinate expression of a <jl-8 1 map for
`showing correspondence between a steering angle <P and a
`target control angle 81 ;
`FIG. 7 is a coordinate expression of a Ve-K map for
`showing correspondence between an eye movement speed
`Ve and a optimum control speed K; and
`FIG. 8 is a view showing change of the steering angle <P
`and change of the target control angle 8 in comparison.
`
`40
`
`DETAILED DESCRIPTION OF THE
`PREFERRED EMBODIMENT
`
`Hereinafter, a preferred embodiment of the present inven-
`tion will be described with reference to FIGS. 1 to 8.
`A vehicle 1 of the preferred embodiment has head lights
`2 for lighting the space in front of the vehicle installed such
`that they are swingable in a rightward and leftward hori(cid:173)
`zontal direction. FIG. 1 is a view for showing the vehicle 1
`from above and in this figure, the right and left head lights
`2, 2 are swung rightward so as to cause the right forward
`regions to become lighting regions 3, 3.
`The right and left head lights 2, 2 are swung together in
`the same direction by the same angle and as shown in FIG.
`1, angles of their optical axes L, L with respect to an
`advancing direction of the vehicle, i.e. lighting angle, are
`both set to be 8. Regarding the angle 8, that on the right side
`with respect to the advancing direction is given plus sign and
`that on the left side is given minus sign.
`Alternatively, only a head light on the turning side may be
`swung or the right and left head lights may be swung by
`respective angles different from each other.
`A swinging mechanism for swinging the head light 2 in
`the preferred embodiment is schematically shown in FIG. 2,
`wherein a lamp unit 4 of the head light 2 is fixed to a rotary
`shaft 5, and a worm gear 7 formed at the end of a driving
`
`Page 9 of 12
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`

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`5,931,572
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`15
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`35
`
`5
`lighting angle from the present lighting angle 80 to the target
`control angle 81 during 1 cycle. When the target control
`speed 18 1-80 1/d is larger than the optimum control speed K,
`the flow advances to Step 4 where the target control speed
`81 and the present lighting angle 80 are compared to dis(cid:173)
`criminate whether the light axis is to be changed rightward
`or leftward. If rightward, the flow advances to Step 5 and a
`final control angle 8 for 1 cycle is set at 80 +Kxd. If leftward.
`the flow advances to Step 6 and the final control angle 8 for
`1 cycle is set at 80 -Kxd.
`Namely, when the target control speed 181 -8 01/d exceeds
`the optimum control speed K, the final control angle 8 is
`decided so as to restrain changing speed of the lighting angle
`to the optimum control speed K for avoiding the situation
`that the changing speed of the lighting angle becomes
`extremely large and gives the driver a sense of incongruity.
`Since the optimum control speed K is proportional to the eye
`moving speed Ve, when the eye moving speed Ve is fast and
`degree of strain of the driver is supposed to be high, the
`changing speed of the lighting angle is also made fast to
`meet the driver's sense and intention.
`On the other hand, when the target control speed 18 1-80 1/d
`does not reach the optimum control speed K at Step 3, the
`flow jumps to Step 7 where the final control angle 8 is set
`at the target control angle 81 . That is, changing of the
`lighting region is carried out at the target control speed
`l81-8ol!d.
`A control signal based on the final control angle 8 decided
`in the manner as described above is outputted to the motor
`driver 14 for driving and controlling the motor 8. FIG. 8 30
`shows an example of change of the final control angle 8. The
`upper portion of FIG. 8 shows change of the steering angle
`<jJ and the lower portion shows change of the final control
`angle 8. The both have a common horizontal time axis.
`The target control angle 81 also changes in a similar
`manner as the steering angle <jJ since the target control angle
`81 is proportional to the steering angle <jJ except in the
`nonresponsive zone. When the steering angle <jJ changes
`gently, the final control angle 8 coincides with the target
`control angle 81 (Step 7 in FIG. 5), therefore the final control
`angle 8 changes in a similar manner as the steering angle <jl.
`However, when the steering angle <jJ changes rapidly (Ta
`and Tb sections in FIG. 8), the final control angle changes
`gently being restrained to the optimum control speed K 45
`(Step 5 or 6 in FIG. 5).
`In case that the steering handle is returned rapidly as in the
`Ta and Tb sections in FIG. 8, according to a conventional
`technique the lighting region is also changed rapidly to give
`the driver a sense of incongruity. According to the present
`embodiment, however, the lighting region is changed at a
`smoothed speed not giving the driver the sense of incon(cid:173)
`gruity because the change of the final control angle is
`restrained to the optimum control speed K.
`In addition, since the optimum control speed K is pro(cid:173)
`portional to the eye moving speed Ve, the lighting region is
`changed at a speed suitable for the degree of strain of the
`driver to meet the driver's sense and intention.
`Though degree of strain of the driver is judged from the
`eye moving speed Ve in the above embodiment, heart rate of
`the driver may be measured by sensor 15 in place of the eye
`moving speed Ve. In this case, it is necessary to attach a heart
`rate sensor to the driver's arm for example.
`The degree of strain is judged from fluctuation of intervals
`of heartbeats or the like by analyzing the heart rate using 65
`apparatus 16, and a map of the optimum control speed K
`corresponding to the degree of strain based on the driver's
`
`6
`heart rate is prepared beforehand similarly to the case of the
`eye moving speed Ve. This optimum control speed is used
`for controlling change of the lighting region in such manner
`that when the degree of strain is high the lighting region is
`5 changed fast and when the degree of strain is low the
`lighting region is changed slowly.
`Skin electric potential of the driver also shows the degree
`of strain as measured by sensor 17. When the degree of
`strain is high, the driver's hand or the like is sweaty, which
`10 lowers the skin electric potential. Therefore, if the skin
`electric potential of the driver is measured, the result can be
`applied using apparatus 18 in the same way as the above(cid:173)
`mentioned eye moving speed Ve and heart rate.
`Further, a brain wave or the like is also applicable.
`In the foregoing, degree of strain of the driver is judged
`directly from a change of his own body, however it is also
`possible to judge the degree of strain from an operation state
`of the vehicle indirectly. For example, when the vehicle
`speed is high, the degree of strain can be judged high
`because the driver is required to perform more careful
`20 operation as the vehicle speed increases. Or the degree of
`strain can be judged by analyzing change of the vehicle
`speed too, to some extent.
`Similarly, the degree of strain can be judged by analyzing
`movement of the steering wheel, that is, change of the
`25 steering angle <jJ too. When the steering angle <jJ changes
`frequently, degree of strain can be supposed high, generally.
`Further, degree of strain of the driver can be judged by
`analyzing turning movement of the vehicle body such as
`yaw rate or lateral acceleration G.
`Preferably, a map of the optimum control speed K corre-
`sponding to the degree of strain of the driver analyzed from
`the operation state of the vehicle is prepared beforehand to
`be applied for controlling change of the lighting region in the
`same manner as the foregoing.
`In a vehicle having a navigation system mounted therein,
`map information is stored and then output using means 21
`and a present position of the proper vehicle on the map can
`be detected by means 22 and , therefore, a computer can
`recognize a state in front of the vehicle of a road on which
`40 the vehicle is now travelling . From the state of the road in
`front of the vehicle such as a curve, a straight course or a
`crossing, the degree of strain of the driver can be judged to
`some extent.
`In case of curves continuing or at a crossing, it may be
`judged that degree of strain of the driver increases and in
`case of straight courses continuing, may be judged that the
`degree of strain is low. Therefore, a pertinent light distribu(cid:173)
`tion control giving no sense of incongruity to the driver can
`be carried out by inputting information of the state of the
`50 road in front of the vehicle from the navigation system,
`analyzing the information to judge the degree of strain of the
`driver and applying the result to control of change of the
`lighting region in the same manner as aforementioned
`control based on detected characteristics of the driver and
`55 the detected operation states of the vehicle. Although there
`has been described what is at present considered to be the
`preferred embodiment of the invention, it will be understood
`by those skilled in the art that variations and modifications
`may be made thereto without departing from the spirit or
`60 essence of the invention. The scope of the invention is,
`therefore, indicated by the appended claims, rather than the
`foregoing description of the presently preferred embodi(cid:173)
`ment.
`What is claimed is:
`1. A head lamp device for a vehicle capable of changing
`a lighting region in front of the vehicle in rightward and
`leftward directions, said device comprises:
`
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`7
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`5,931,572
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`8
`lighting region changing means for changing a lighting
`region of the head lamp;
`operation state detecting means for detecting an operation
`state of the vehicle;
`strain degree judging means for judging a degree of strain
`of the driver by analyzing information detected by said
`operation state detecting means; and
`control means for controlling said lighting region chang(cid:173)
`ing means based on information judged by said strain
`degree judging means, and
`said control means adjusts at least one of amount of
`change and speed of change of the lighting region in
`accordance with the detected degree of strain of the
`driver.
`11. A head lamp device for a vehicle as claimed in claim
`10, wherein said operation state detecting means includes a
`vehicle speed sensor for detecting vehicle speed, and said
`strain degree judging means judges the degree of strain of
`the driver by analyzing the vehicle speed detected by said
`vehicle speed sensor.
`12. A head lamp device for a vehicle as claimed in claim
`10, wherein said operation state detecting means includes a
`steering angle sensor for detecting a steering angle, and said
`25 strain degree judging means judges the degree of strain of
`the driver by analyzing the steering angle detected by said
`steering angle sensor.
`13. A head lamp device for a vehicle as claimed in claim
`10, wherein said operation state detecting means includes a
`turning movement sensor for detecting turning movement of
`a body of the vehicle, and said strain degree judging means
`judges the degree of strain of the driver by analyzing the
`turning movement detected by said turning movement sen(cid:173)
`sor.
`14. Ahead lamp device for a vehicle capable of changing
`a lighting region in front of the vehicle in rightward and
`leftward directions, said device comprises:
`a head lamp:
`lighting region changing means for changing the lighting
`region of the lamp;
`map information outputting means for outputting map
`information representing a map;
`present position detecting means for detecting a present
`position of a proper vehicle on the map;
`strain degree judging means for judging a degree of strain
`of the driver based on said map information outputted
`by said map information outputting means and said
`present position of the proper vehicle detected by said
`present position detecting means; and
`control means for controlling said lighting region chang(cid:173)
`ing means based on information judged by said strain
`degree judging means, and
`said control means adjusts at least one of amount of
`change and speed of change of the lighting region in
`accordance with degree of strain of the driver judged
`from a state of road in front of the proper vehicle.
`15. A head lamp device for a vehicle as defined in claim
`14, wherein said strain degree judging means determines the
`state of the road in front of the proper vehicle based on said
`map information output by said map information outputting
`means and the present position of the proper vehicle
`detected by said present position detecting means.
`
`5
`
`a head lamp;
`lighting region changing means for changing a lighting
`region of the head lamp;
`strain degree judging means for judging a degree of strain
`of a driver; and
`control means for controlling said lighting region chang(cid:173)
`ing means based on information judged by said strain
`degree judging means, and
`said control means adjusts at least one of amount of 10
`change and speed of change of the lighting region in
`accordance with the judged degree of strain of the
`driver.
`2. A head lamp device for a vehicle as defined in claim 1,
`wherein said strain degree judging means comprises means 15
`for detecting the degree of strain of the driver by detecting
`and analyzing a characteristic of the driver.
`3. A head lamp device for a vehicle as claimed in claim
`2, wherein said strain degree detecting means detects the
`degree of strain of the driver by analyzing movement of an 20
`eye of the driver.
`4. A head lamp device for a vehicle as claimed in claim
`2, wherein said strain degree detecting means detects the
`degree of strain of the driver by analyzing at least one of
`heart rate and skin electric potential of the driver.
`5. A head lamp device for a vehicle as claimed in claim
`2, wherein said detecting means detects at least one of
`movement of an eye of the driver, heart rate of the driver and
`skin electric potential of the driver.
`6. A head lamp device for a vehicle as claimed in claim 30
`1, wherein said strain degree judging means comprises
`operation state detecting means for detecting an operation
`state of the vehicle, and said strain degree judging means
`judges the degree of driver strain by analyzing information
`detected by said operation state detecting means.
`7. A head lamp device for a vehicle as claimed in claim
`6, wherein said operation state detecting means detects at
`least one of vehicle speed, a steering angle of the vehicle,
`and turning movement of the vehicle.
`8. A head lamp device for a vehicle as claimed in claim 40
`1, wherein said strain degree judging means comprises map
`information outputting means for outputting map informa(cid:173)
`tion representing a map and present position detecting
`means for detecting a present position of a proper vehicle on
`the map; said strain degree judging means determines a state 45
`of road in front of the proper vehicle based on the map
`information output by said map information outputting
`means and the detected proper position of the vehicle, and
`said strain degree judging means judges the degree of driver
`strain by analyzing the state of road in front of the proper 50
`vehicle.
`9. A head lamp device for a vehicle as claimed in claim
`1, wherein said control means determines at least one of a
`target am