JP2008055941A - Night forward information offering device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To automatically adjust illuminance of an infrared ray projector according to changes of various traveling situations while driving a vehicle in a night forward information offering device. <P>SOLUTION: The device collects information showing a status of the vehicle while travelling of the vehicle, analyzes the traveling situation of the vehicle based on the information, and adjusts the illuminance of the infrared ray projector based on the analysis result. For example, the information showing the status of the vehicle includes car speed information, operation information of a turn indicator, beam direction information of a head lamp, and operation information of a brake. At the time of adjustment, it is preferable to give a predetermined delay time for adjusting the illuminance from an off state to a lit state. The illuminance of the infrared ray projector can be changed according to a predetermined rate of change. The rate of change can be determined in accordance with combination of types of traveling situations of the vehicle before/after changing the illuminance. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an apparatus for providing information on the front side of a vehicle such as discovery of a pedestrian at night to a driver. It is particularly suitable for use in large commercial vehicles such as trucks and buses.

  There has been proposed a night front information providing apparatus that provides information on the front of a vehicle such as discovery of a pedestrian at night to a driver (see, for example, Patent Documents 1 to 3). This device includes a display unit such as a head-up display (HUD), and displays information ahead of the vehicle on this display unit.

  Moreover, the night front information provision apparatus is equipped with the infrared projector, and the camera imaging | photography at night is enabled by irradiating the front of a vehicle with infrared rays (for example, refer patent document 4).

JP-A-8-175228 JP 9-43532 A JP 2003-291688 A Japanese Patent Laid-Open No. 2005-50139 Japanese Patent Laid-Open No. 7-312142

  The infrared projector used in the night front information providing apparatus is always in a state of projecting with a high beam and has a short life. In particular, trucks and buses are often used for long-distance transportation at night. Compared with ordinary passenger cars, the frequency of use of infrared projectors is extremely high. For example, many reports of a lifetime of only two months have been received. Is the current situation.

  As a proposal for extending the life of the infrared projector, as detected in Patent Document 4, when it is detected that the vehicle is traveling in a traveling environment that does not require light projection, the infrared light projection is stopped. Or there is a proposal to reduce the amount of infrared light.

  However, the proposal of patent document 4 is a proposal for applying to a passenger car, and it is difficult to apply as it is to large commercial vehicles such as trucks and buses. For example, in the determination of “traveling environment that does not require light projection” in the proposal of Patent Document 4, determination criteria such as ambient brightness and whether there is traffic jam are mainly used.

  However, considering the situation where trucks and buses are transporting long distances at night, the roads on which they are traveling are highways or main highways, and the time to pass through the downtown is very short. Therefore, judgment criteria such as the brightness of the surroundings and whether or not the vehicle is in a traffic jam are not appropriate. Therefore, new proposals for large commercial vehicles such as trucks and buses are necessary.

  The present invention has been made under such a background, and provides night front information capable of automatically adjusting the illuminance of the infrared projector according to changes in various driving conditions during driving of the vehicle. An object is to provide an apparatus.

  The present invention is a night front information providing apparatus that includes an infrared projector and displays information on the front of the vehicle at night on a display unit. The feature of the present invention is that the state of the vehicle while the vehicle is running There are provided means for collecting the information to be shown and analyzing the traveling state of the vehicle based on the information, and means for adjusting the illuminance of the infrared projector based on the analysis result of the analyzing means.

  For example, the information indicating the state of the vehicle includes vehicle speed information, direction indicator operation information, headlamp beam direction information, and brake operation information.

  According to this, the illuminance of the infrared projector can be adjusted in accordance with changes in various traveling conditions during driving. For example, in a situation where the headlight is a low beam and the vehicle is traveling straight at a vehicle speed that is close to the upper limit of the legal speed, it is a situation that requires the most nighttime forward information providing device. can do.

  On the other hand, when turning right or left at an intersection or changing lanes, it is necessary to check the surroundings of the vehicle.Therefore, the need for a night information providing device is low, and under such circumstances, the illuminance of the infrared projector is reduced. Can be lowered. In addition, the necessity for a night front information providing device is low even when the vehicle is stopped. Under such circumstances, the illuminance of the infrared projector can be lowered. Alternatively, if the headlamp is traveling with a high beam, the necessity for a night front information providing device is low, and the illuminance of the infrared projector can be reduced under such circumstances.

  Furthermore, the means for adjusting may include means for giving a predetermined delay time when adjusting the illuminance from the extinguished state to the lit state.

  According to this, the lifetime can be expected to be extended by suppressing the inrush current of the infrared projector. For example, when the vehicle is turned off when it is stopped and turned on while driving, it takes longer time to accelerate when starting from a stopped state for large commercial vehicles such as trucks and buses than for passenger cars. There is no problem caused by taking a long time for the infrared projector to transition from the extinguished state to the lit state.

  Further, the means for adjusting may include means for changing the illuminance of the infrared projector according to a predetermined rate of change.

  The rate of change may be determined in accordance with a combination of a type of vehicle traveling state before the change and a type of vehicle traveling state after the change in the changing means.

  For example, in the proposal of Patent Document 4, the change in illuminance has two steps of an upper limit or a lower limit. However, in the present invention, this can be further changed in a plurality of steps or steplessly. At this time, by setting the illuminance change pattern in detail according to the type of vehicle driving situation, the illuminance is set to the minimum necessary according to the type of vehicle driving condition, and further extension of the life of the infrared projector is expected. be able to.

  ADVANTAGE OF THE INVENTION According to this invention, the illumination intensity of an infrared projector can be automatically adjusted according to the change of the various driving | running | working conditions during driving | running | working of a vehicle, and the lifetime of an infrared projector can be extended compared with the past.

  A night front information providing apparatus according to an embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a diagram showing a driver's cab of a vehicle equipped with the night front information providing apparatus of this embodiment.

  As shown in FIG. 1, the present embodiment is a night front information providing apparatus 1 that includes an infrared projector 5 and displays an image of information in front of a vehicle at night on a HUD 3 that is a display unit. Here, the feature of the night front information providing apparatus 1 of the present embodiment is that it collects information indicating the state of the vehicle while the vehicle is traveling, and analyzes the traveling state of the vehicle based on the information. The unit 30 and the illuminance adjusting unit 20 that adjusts the illuminance of the infrared projector 5 based on the analysis result of the traveling state analyzing unit 30 are provided. In addition, about the adjustment method of illumination intensity, all the existing methods are applicable.

  The vehicle state information includes vehicle speed information from the vehicle speed sensor 10, direction indicator operation information from the direction indicator switch 7, headlamp beam direction information from the headlamp switch 9, and brake switch 6. Includes brake activation information. The brake operation information from the brake switch 6 includes auxiliary brake operation information in addition to main brake operation information such as a disc brake.

  Further, rain information can be obtained by the wiper switch 8. Further, information for identifying day and night by the solar radiation sensor 11 and information for recognizing that the vehicle is traveling in the tunnel can be obtained.

  The camera 4 is a camera device that captures infrared rays, and the night front information providing device 1 displays an infrared image emitted from the body of the pedestrian captured by the camera 4 on the HUD 3 via the projector 2. The infrared projector 5 irradiates the front of the vehicle with infrared rays, and the camera 4 captures the situation around the pedestrian.

  Next, the illuminance adjustment procedure in the illuminance adjustment unit 20 will be described with reference to FIG. FIG. 2 is a flowchart showing the illuminance adjustment procedure of the illuminance adjustment unit 20. As shown in FIG. 2, the illuminance adjustment unit 20 is in the parking state (S3) while the power switch is not turned on (S1). It should be noted that the illuminance is in the parking state, that is, the illuminance is “0” and the night front information providing apparatus 1 itself is stopped. However, even when the power switch is turned on (S1) and the night front information providing apparatus 1 is in the operating state, it is identified that the present day is daytime by the information for identifying day and night obtained from the solar radiation sensor 11. Sometimes (S2), too, the illuminance is parked (S3). Alternatively, the power supply may be automatically turned off until the information for identifying day and night obtained from the solar radiation sensor 11 indicates nighttime even when the power switch is turned on. Even during daytime, it is identified as nighttime during tunnel travel.

  The power switch is in the ON state (S1), the information for identifying day and night obtained from the solar radiation sensor 11 indicates the night (S2), and the vehicle speed is 0 km / h to V1 (for example, 30 km / h) ( S4) When the operation of the direction indicator is confirmed by the direction indicator switch 7 (S5), the illuminance is set to the right or left turn state (S6). The illuminance in the right / left turn state is the illuminance level “1” when the highest illuminance state is set to the illuminance level “5”. In the right / left turn state, the necessity for the night front information providing device 1 is low. Is taken into consideration so that the life of the infrared projector 5 is extended.

  Further, when the vehicle speed is 0 km / h or more and V1 or less (S4) and the operation of the direction indicator is not confirmed by the direction indicator switch 7 (S5), the illuminance is set to a low speed state (S8). The illuminance in the low speed state is the illuminance level “2”. In the low speed state, the necessity for the night front information providing apparatus 1 is low, and consideration is given to reducing the illuminance and extending the life of the infrared projector 5. . However, if it is determined that it is raining by detecting the operation of the wiper by the wiper switch 8 (S7), the illuminance level is "+1" because the visibility is worse than in fine weather (S9). .

  When the vehicle speed is higher than V1 (S4), when the operation of the direction indicator is confirmed by the direction indicator switch 7 (S10), the illuminance is changed to the lane change state (S11). The illuminance in the lane change state is the illuminance level “1”. In the lane change state, the necessity for the night front information providing device 1 is low, and consideration is given to extending the life of the infrared projector 5 by reducing the illuminance. ing.

  Further, if the vehicle speed is higher than V1 (S4), the operation of the direction indicator is not confirmed by the direction indicator switch 7 (S10). At this time, if sudden deceleration is confirmed by the brake switch 6 or the vehicle speed sensor 10 ( S12), the illuminance is suddenly decelerated (S13). The illuminance in the rapid deceleration state is the illuminance level “1”. In the rapid deceleration state, the necessity for the night front information providing device 1 is low, and consideration is given to extending the life of the infrared projector 5 by reducing the illuminance. ing.

  If the vehicle speed is higher than V1 (S4), the operation of the direction indicator is not confirmed (S10), the sudden deceleration is not confirmed (S12), and the headlamp switch 9 confirms the low beam ( S14) Since the vehicle is traveling straight on a general road and the night front information providing device 1 is most useful, the illuminance is set to the normal state (S15). The illuminance in the normal state is the illuminance level “5”, which is the highest illuminance level.

  Further, the vehicle speed is higher than V1 (S4), the operation of the direction indicator is not confirmed (S10), the sudden deceleration is not confirmed (S12), and the headlamp switch 9 confirms the high beam (S14). Furthermore, if the vehicle speed is V2 (for example, 60 km / h) or more (S16), the illuminance is set to a high speed state (S21). The illuminance in the high speed state is the illuminance level “4”, which is lower than that in the normal state. This is because, in high speed conditions, the car is mainly driving on a highway, so there is little need to pay attention to the presence of pedestrians. Furthermore, because the headlamp is a high beam, the front can be visually confirmed almost completely. It is. However, as described above, when the wiper switch 8 can determine that it is raining (S20), the illuminance is "+1" (S22).

  Further, the vehicle speed is higher than V1 (S4), the operation of the direction indicator is not confirmed (S10), the sudden deceleration is not confirmed (S12), and the headlamp switch 9 confirms the high beam (S14). Further, if the vehicle speed is less than V2 (S16), the illuminance is set to a medium speed state (S18). The illuminance in the medium speed state is the illuminance level “3”, which is lower than that in the high speed state. This is because, in the medium speed state, the road is mainly traveling on a general road, and the need to pay attention to the presence of pedestrians is higher than that on the highway, but the speed is medium and the headlamps are high beams. This is because the front can be completely visually confirmed with a margin. However, as described above, when the wiper switch 8 can determine that it is raining (S17), the illuminance is incremented by "+1" (S19). The relationship between the traveling state and illuminance described above is shown as a list in FIG.

  The illuminance adjustment unit 20 changes the illuminance of the infrared projector 5 according to a predetermined change rate. This rate of change is determined in accordance with the combination of the type of vehicle driving status before the change and the type of vehicle driving status after the change. An example of the change rate list is shown in FIG. In addition, here, in order to make the explanation easy to understand, the explanation will be made without considering the extra illuminance level at the time of rainfall.

  In the list of FIG. 4, the change rate of 100% means a state in which the illuminance changes instantaneously, and it means that the time required for the change of illuminance takes longer as the percentage value becomes smaller. For example, if the change rate is 10%, the time required for the change in illuminance is about 5 seconds. If the rate of change is 30%, the time required for the change in illuminance is about 4 seconds. If the rate of change is 50%, the time required for the change in illuminance is about 3 seconds. If the rate of change is 70%, the time required for the change in illuminance is about 2 seconds. If the rate of change is 90%, the time required for the change in illuminance is about 1 second.

  The driving condition of the vehicle before the illuminance change is “normal (illuminance level 5)”, and the driving condition of the vehicle after the illuminance change is “low speed (illuminance level 2)”, “medium speed (illuminance level 3)”, “high speed”. In the case of “(illuminance level 4)”, the change rate is 90%, and the illuminance level changes in about 1 second. These changes are changes from high illuminance to low illuminance (−1 to −3), and are assumed to be early (about 1 second) in order to extend the life of the infrared projector 5.

  The driving situation of the vehicle before the illuminance change is “normal (illuminance level 5)”, and the driving situation of the vehicle after the illuminance change is “parking (illuminance level 0)”, “turn left / right (illuminance level 1)”, “lane” In the case of “change (illuminance level 1)” and “rapid deceleration (illuminance level 1)”, the rate of change is 100%, and the illuminance level changes instantaneously. These changes are changes from high illuminance to low illuminance (−4 to −5), and are assumed to be instantaneous changes in order to extend the life of the infrared projector 5.

  The driving situation of the vehicle before the illuminance change is “low speed (illuminance level 2)”, and the driving situation of the vehicle after the illuminance change is “normal (illuminance level 5)”, “medium speed (illuminance level 3)”, “high speed”. In the case of (illuminance level 4) ", the change rates are 30%, 70%, and 50%, respectively, and the illuminance level changes in about 2 to 4 seconds. These changes are changes from low illuminance to high illuminance (+1 to +3), and the change is about 2 to 4 seconds in order to avoid a rapid temperature rise of the filament and extend the life of the infrared projector 5. .

  The driving situation of the vehicle before the illuminance change is “low speed (illuminance level 2)”, and the driving situation of the vehicle after the illuminance change is “parking (illuminance level 0)”, “turn left / right (illuminance level 1)”, “lane” In the case of “change (illuminance level 1)” and “rapid deceleration (illuminance level 1)”, the rate of change is 100%, and the illuminance level changes instantaneously. These changes are changes from high illuminance to low illuminance (−1 to −2), and are assumed to be instantaneous changes in order to extend the life of the infrared projector 5.

  When the driving situation of the vehicle before the illuminance change is “medium speed (illuminance level 3)” and the driving situation of the vehicle after the illuminance change is “normal (illuminance level 5)”, the rate of change is 50%. Yes, the illuminance level changes in about 3 seconds. This change is a change from low illuminance to high illuminance (+2), and is assumed to be a change of about 3 seconds in order to avoid a rapid temperature rise of the filament and extend the life of the infrared projector 5.

  When the driving situation of the vehicle before the illuminance change is “medium speed (illuminance level 3)” and the driving situation of the vehicle after the illuminance change is “low speed (illuminance level 2)”, the rate of change is 90%. Yes, the illuminance level changes in about 1 second. This change is a change (−1) from high illuminance to low illuminance, and is assumed to be early (about 1 second) in order to extend the life of the infrared projector 5.

  When the driving situation of the vehicle before the illuminance change is “medium speed (illuminance level 3)” and the driving situation of the vehicle after the illuminance change is “high speed (illuminance level 4)”, the rate of change is 70%. Yes, the illuminance level changes in about 2 seconds. This change is a change (+1) from low illuminance to high illuminance, and is assumed to be a change of about 2 seconds in order to avoid a rapid temperature rise of the filament and extend the life of the infrared projector 5.

  The vehicle running status before the illuminance change is “medium speed (illuminance level 3)”, and the vehicle running status after the illuminance change is “parking (illuminance level 0)”, “right / left turn (illuminance level 1)”, “ In the case of “lane change (illuminance level 1)” and “rapid deceleration (illuminance level 1)”, the rate of change is 100%, and the illuminance level changes instantaneously. These changes are changes from high illuminance to low illuminance (−2 to −3), and are assumed to be instantaneous changes in order to extend the life of the infrared projector 5.

  When the driving condition of the vehicle before the illuminance change is “high speed (illuminance level 4)” and the driving condition of the vehicle after the illuminance change is “normal (illuminance level 5)”, the rate of change is 70%. The illuminance level changes in about 2 seconds. This change is a change (+1) from low illuminance to high illuminance, and is assumed to be a change of about 2 seconds in order to avoid a rapid temperature rise of the filament and extend the life of the infrared projector 5.

  When the driving condition of the vehicle before the illuminance change is “high speed (illuminance level 4)” and the driving condition of the vehicle after the illuminance change is “low speed (illuminance level 2)”, “medium speed (illuminance level 3)” The change rate is 100%, and the illuminance level changes instantaneously. This change is a change from high illuminance to low illuminance (−1 to −2), and is assumed to be an instantaneous change in order to extend the life of the infrared projector 5.

  The driving situation of the vehicle before the illuminance change is “high speed (illuminance level 4)”, and the driving situation of the vehicle after the illuminance change is “parking (illuminance level 0)”, “right / left turn (illuminance level 1)”, “lane” In the case of “change (illuminance level 1)” and “rapid deceleration (illuminance level 1)”, the rate of change is 100%, and the illuminance level changes instantaneously. These changes are changes from high illuminance to low illuminance (−3 to −4), and are assumed to be instantaneous changes in order to extend the life of the infrared projector 5.

  When the driving situation of the vehicle before the illuminance change is “parking (illuminance level 0)” and the driving situation of the vehicle after the illuminance change is “normal (illuminance level 5)”, the rate of change is 10%. The illuminance level changes in about 5 seconds. This change is a change from the minimum illuminance to the maximum illuminance (+5). In particular, an inrush current is generated at the rise from the time when the illuminance level “0” is extinguished. In order to prolong the life of the projector 5, the slowest change is about 5 seconds. In addition, even the most gradual change is not a problem because it takes a considerable time for the vehicle to accelerate from the “parking” state to the “normal” state.

  When the driving situation of the vehicle before the illuminance change is “parking (illuminance level 0)” and the driving situation of the vehicle after the illuminance change is “low speed (illuminance level 2)”, “medium speed (illuminance level 3)” The change rates are 50% and 30%, respectively, and the illuminance level changes in about 3 to 4 seconds. These changes are changes from low illuminance to high illuminance (+2 to +3). In particular, inrush current is generated at the rise from the time when the illuminance level is “0”, so the occurrence of inrush current is suppressed. In order to extend the life of the infrared projector 5, a gradual change is made for about 3 to 4 seconds.

  When the driving situation of the vehicle before the illuminance change is “parking (illuminance level 0)” and the driving situation of the vehicle after the illuminance change is “high speed (illuminance level 4)”, the rate of change is 10%. The illuminance level changes in about 5 seconds. This change is a change from low illuminance to high illuminance (+4). In particular, since an inrush current is generated at the rise of the illuminance level “0” from the time when the light is extinguished, the generation of the inrush current is suppressed, and infrared rays are reduced. In order to extend the life of the projector 5, a gentle change of about 5 seconds is used. Even if such a gradual change occurs, there is no problem because it takes a considerable time for the vehicle to accelerate from the “parking” situation to the “high speed” situation.

  When the driving condition of the vehicle before the illuminance change is “right / left turn (illuminance level 1)” and the driving condition of the vehicle after the illuminance change is “normal (illuminance level 5)”, the rate of change is 10%. Yes, the illuminance level changes in about 5 seconds. This change is a change from low illuminance to high illuminance (+4), and is assumed to be a change of about 5 seconds in order to avoid a rapid temperature rise of the filament and extend the life of the infrared projector 5. In addition, such a gradual change is not a problem because it takes a considerable time for the vehicle to accelerate from the “right / left turn” situation to the “normal” situation.

  When the driving condition of the vehicle before the illuminance change is “right / left turn (illuminance level 1)” and the driving condition of the vehicle after the illuminance change is “low speed (illuminance level 2)”, the rate of change is 70%. Yes, the illuminance level changes in about 2 seconds. This change is a change (+1) from low illuminance to high illuminance, and is assumed to be a change of about 2 seconds in order to avoid a rapid temperature rise of the filament and extend the life of the infrared projector 5.

  When the driving condition of the vehicle before the illuminance change is “right / left turn (illuminance level 1)” and the driving condition of the vehicle after the illuminance change is “medium speed (illuminance level 3)”, the rate of change is 50%. The illuminance level changes in about 3 seconds. This change is a change from low illuminance to high illuminance (+2), and is assumed to be a change of about 3 seconds in order to avoid a rapid temperature rise of the filament and extend the life of the infrared projector 5.

  When the driving situation of the vehicle before the illuminance change is “right / left turn (illuminance level 1)” and the driving situation of the vehicle after the illuminance change is “high speed (illuminance level 4)”, the rate of change is 30%. Yes, the illuminance level changes in about 4 seconds. This change is a change from low illuminance to high illuminance (+3), and is assumed to be a change of about 4 seconds in order to avoid a rapid temperature rise of the filament and extend the life of the infrared projector 5. In addition, such a gradual change is not a problem because it takes a considerable amount of time for the vehicle to accelerate from a “right / left turn” situation to a “high speed” situation.

  The driving situation of the vehicle before the illuminance change is “left / right turn (illuminance level 1)”, and the driving situation of the vehicle after the illuminance change is “parking (illuminance level 0)”, “lane change (illuminance level 1)”, “ In the case of “sudden deceleration (illuminance level 1)”, the rate of change is 100%, and the illuminance level changes instantaneously. These changes are changes from high illuminance to low illuminance or the same illuminance (−1 to 0), and are assumed to be instantaneous changes in order to extend the life of the infrared projector 5.

  When the driving situation of the vehicle before the illuminance change is “lane change (illuminance level 1)” and the driving situation of the vehicle after the illuminance change is “normal (illuminance level 5)”, the rate of change is 70%. Yes, the illuminance level changes in about 2 seconds. This change is a relatively large change (+4) from low illuminance to high illuminance, and in order to extend the life of the infrared projector 5 by avoiding a rapid temperature rise of the filament, the change rate should be smaller. Although it is desirable, after a lane change, it will be a slightly early change of about 2 seconds in order to immediately become a “normal” situation.

  When the driving situation of the vehicle before the illuminance change is “lane change (illuminance level 1)” and the driving situation of the vehicle after the illuminance change is “low speed (illuminance level 2)”, the rate of change is 70%. Yes, the illuminance level changes in about 2 seconds. This change is a change (+1) from low illuminance to high illuminance, and is assumed to be a change of about 2 seconds in order to avoid a rapid temperature rise of the filament and extend the life of the infrared projector 5.

  When the driving condition of the vehicle before the illuminance change is “lane change (illuminance level 1)” and the driving condition of the vehicle after the illuminance change is “medium speed (illuminance level 3)”, the rate of change is 50%. The illuminance level changes in about 3 seconds. This change is a change from low illuminance to high illuminance (+2), and is assumed to be a change of about 3 seconds in order to avoid a rapid temperature rise of the filament and extend the life of the infrared projector 5.

  When the driving situation of the vehicle before the illuminance change is “lane change (illuminance level 1)” and the driving situation of the vehicle after the illuminance change is “high speed (illuminance level 4)”, the rate of change is 30%. Yes, the illuminance level changes in about 4 seconds. This change is a change from low illuminance to high illuminance (+3), and is assumed to be a change of about 4 seconds in order to avoid a rapid temperature rise of the filament and extend the life of the infrared projector 5.

  The rate of change from “lane change” to “normal” was 70% (about 2 seconds), whereas the rate of change from “lane change” to “high speed” was 30% (about 4 seconds). The reason for the loosening is that it is driving on a highway under “high speed” conditions, and there may be pedestrians ahead of the road compared to “normal” driving conditions on general roads. This is because the nature is low.

  The driving situation of the vehicle before the illuminance change is “lane change (illuminance level 1)”, and the driving situation of the vehicle after the illuminance change is “parking (illuminance level 0)”, “right / left turn (illuminance level 1)”, “ In the case of “sudden deceleration (illuminance level 1)”, the rate of change is 100%, and the illuminance level changes instantaneously. These changes are changes from high illuminance to low illuminance or the same illuminance (−1 to 0), and are assumed to be instantaneous changes in order to extend the life of the infrared projector 5.

  When the driving situation of the vehicle before the illuminance change is “rapid deceleration (illuminance level 1)” and the driving situation of the vehicle after the illuminance change is “normal (illuminance level 5)”, the rate of change is 10%. Yes, the illuminance level changes in about 5 seconds. This change is a change from low illuminance to high illuminance (+4), and is assumed to be a change of about 5 seconds in order to avoid a rapid temperature rise of the filament and extend the life of the infrared projector 5. Even if such a gradual change occurs, there is no problem because it takes a considerable time for the vehicle to accelerate from the “rapid deceleration” situation to the “normal” situation.

  When the driving situation of the vehicle before the illuminance change is “rapid deceleration (illuminance level 1)” and the driving situation of the vehicle after the illuminance change is “low speed (illuminance level 2)”, the rate of change is 70%. Yes, the illuminance level changes in about 2 seconds. This change is a change (+1) from low illuminance to high illuminance, and is assumed to be a change of about 2 seconds in order to avoid a rapid temperature rise of the filament and extend the life of the infrared projector 5.

  The rate of change is 50% when the driving situation of the vehicle before the illuminance change is “rapid deceleration (illuminance level 1)” and the driving situation of the vehicle after the illuminance change is “medium speed (illuminance level 3)”. The illuminance level changes in about 3 seconds. This change is a change from low illuminance to high illuminance (+2), and is assumed to be a change of about 3 seconds in order to avoid a rapid temperature rise of the filament and extend the life of the infrared projector 5.

  When the driving situation of the vehicle before the illuminance change is “rapid deceleration (illuminance level 1)” and the driving situation of the vehicle after the illuminance change is “high speed (illuminance level 4)”, the rate of change is 30%. Yes, the illuminance level changes in about 4 seconds. This change is a change from low illuminance to high illuminance (+3), and is assumed to be a change of about 4 seconds in order to avoid a rapid temperature rise of the filament and extend the life of the infrared projector 5. Even if such a gradual change occurs, there is no problem because it takes a considerable amount of time for the vehicle to accelerate from the "rapid deceleration" situation to the "high speed" situation.

  The driving situation of the vehicle before the illuminance change is “rapid deceleration (illuminance level 1)”, and the driving situation of the vehicle after the illuminance change is “parking (illuminance level 0)”, “turn left / right (illuminance level 1)”, “ In the case of “lane change (illuminance level 1)”, the rate of change is 100%, and the illuminance level changes instantaneously. These changes are changes from high illuminance to low illuminance or the same illuminance (−1 to 0), and are assumed to be instantaneous changes in order to extend the life of the infrared projector 5.

  In addition, as an application method of illuminance adjustment, a method of changing a voltage applied to the infrared projector 5 using a variable resistor (see, for example, Patent Document 5), a current flowing into the infrared projector 5 using a semiconductor switch, an inverter, or the like. Any existing method can be applied, such as a limiting method.

  According to the present invention, the illuminance of the infrared projector can be automatically adjusted in accordance with changes in various driving conditions during driving of the vehicle, so that the life of the infrared projector can be extended compared to the conventional case. . Thereby, it can contribute to the improvement of the driving safety at night.

The figure which shows the driver's cab of the vehicle carrying the night front information provision apparatus of a present Example. The flowchart which shows operation | movement of the illumination intensity adjustment part of a present Example. The figure which shows the list of the relationship between the driving | running state of a present Example, and illumination intensity. The figure which shows the list of the change rate of the illumination intensity level of a present Example.

Explanation of symbols

1 Night Front Information Providing Device 2 Projector 3 HUD
4 Camera 5 Infrared projector 6 Brake switch 7 Direction indicator switch 8 Wiper switch 9 Headlamp switch 10 Vehicle speed sensor 11 Solar radiation sensor 20 Illuminance adjustment unit 30 Travel condition analysis unit

Claims (5)

In the night front information providing apparatus that includes an infrared projector and displays information on the front of the vehicle at night on the display unit,
Means for collecting information indicating the state of the vehicle during traveling of the vehicle and analyzing the traveling state of the vehicle based on the information;
Means for adjusting the illuminance of the infrared projector based on the analysis result of the analyzing means.   The night front information providing device according to claim 1, wherein the information indicating the state of the vehicle includes vehicle speed information, direction indicator operation information, headlamp beam direction information, and brake operation information.   2. The night front information providing apparatus according to claim 1, wherein the adjusting means includes means for giving a predetermined delay time when adjusting the illuminance from the light extinguished state to the lighting state.   The night front information providing apparatus according to claim 1, wherein the adjusting means includes means for changing the illuminance of the infrared projector according to a predetermined change rate.   5. The night front information providing apparatus according to claim 4, wherein the rate of change is determined in accordance with a combination of a type of a traveling state of the vehicle before the change and a type of the traveling state of the vehicle after the change in the changing unit.

Images