FIELD OF THE INVENTION

The invention relates to a street lighting system comprising one or more street light elements. The invention further relates to the use of such street lighting system as well as to a street provided with such street lighting system.

BACKGROUND OF THE INVENTION

Warning systems for protection from wrong-way drivers are known in the art. US2009/0102683 (US8125349B2), for instance, describes a warning system for protection from wrong-way drivers on freeways and expressways, wherein a warning and/or alarming of a vehicle traveling contrary to the prescribed travel direction is performed using a warning signal, characterized in that the warning signal is an optical and/or acoustic warning signal. The optical warning signal is implemented as a signal board, various signal patterns and/or inscriptions being able to be represented on the signal board. The warning system is mountable on a support element, e.g., a bridge, an overpass, a pillar, and/or a freeway sign or the like.

SUMMARY OF THE INVENTION

Wrong way crashes are often head on collisions that are more likely to produce serious injuries and fatalities. Most of the time the offenders are confused, distracted, or intoxicated drivers who tend to keep their eyes on the road directly in front of them often not seeing roadside warning signals and signs. Driving the wrong way in one-way traffic or on the wrong side of the road was the basis of over 3% of all fatal crashes in the US.

Installing "Do not enter" and "Wrong way" signs can deter drivers from making wrong-way movements onto freeways and other restricted roads by providing the extra visible warning cues standard traffic signs lack. Another solution is flashing LEDs modules on the road surface that is triggered by vehicles moving in the wrong direction.

A GPS-enabled warning system to alert drivers travelling in the wrong direction on motorways may also be applied. Such system may use GPS positioning data, map data and vehicle speed data to determine if the vehicle is travelling against the flow of traffic. The system identifies an area for determining the normal direction of flow, such as around junctions. When the vehicle passes through that area, the system records its direction of travel. If the vehicle enters that area again and the system determines that it's driving in the opposite direction it provides audible and visual warnings.

Above solutions may be complex, vulnerable to (connection) failures, and or may need an additional infrastructure. Further, such solutions may not always be able to cope with changing wrong-way directions during time or due to specific situations. Hence, it is an aspect of the invention to provide an alternative system, which preferably further at least partly obviates one or more of above-described drawbacks. Further, it is an aspect of the invention to provide an alternative system which may in an intuitive way warn the wrong- way driver.

In this invention, we propose glare-based light signaling to alert road users driving the wrong way. The solution may use sensorial information to detect traffic entering from the wrong direction and change the light profile such that the road user will experience glare. The glare (level) can be realized by adaptable optics or activation of LEDs directed at the road with small inclination angles. In an embodiment, an intelligent luminaire is placed along a road with a one-way driving direction and the light profile is configured such that wrong-way drivers will experience glare. The installer can use a hardware switch or a software tool to give in the allowed driving direction. The wrong way driving can be detected by a sensor that extracts the driving direction of vehicles. The luminaire will adapt its optics when a car driving in the wrong way is detected. The wrong driving signal can be propagated through the lighting network to other luminaires along the road to also adapt their optics to create a warning signal. The sensor could be embedded only in the luminaire at the entrance of the road or in every luminaire along the road, etc..

Hence, in a first aspect the invention provides a street lighting system

("system" or "lighting system") comprising one or more street light elements, wherein each street light element comprises a lighting unit (herein sometimes also indicated as

"luminaire") configured for lighting a street with lighting unit light, wherein the street lighting system comprises a control system, especially wherein at least one of the one or more street light elements comprises a control system, wherein at least one street light element comprises a sensor, wherein the control system and the sensor are configured to detect wrong-way traffic (on a street where the street lighting system is implemented to provide street lighting), wherein at least one lighting unit further comprises a second lighting functionality, wherein for providing second light (controlled by said control system) said at least one lighting unit comprises one or more of (i) a redirection element (controlled by said control system) and configured to redirect at least part of the lighting unit light and (ii) an additional light source (controlled by said control system), wherein the street lighting system is further configured to provide said second light in a direction of the wrong-way traffic in dependence of wrong-way traffic being sensed (by said sensor and control system). Hence, a street lighting system comprising one or more street light elements, wherein each street light element comprises a lighting unit for lighting a street with lighting unit light, wherein at least one lighting unit further comprises a second lighting functionality for providing second light in a direction of wrong-way traffic can be used to impose glare (with the second light) to the wrong-way traffic. Hence, the second light, herein also indicated as "glare light", is intended to (re-)alert and/or warn the driver of the wrong-way traffic vehicle to his present traffic situation and can be directed towards the wrong-way traffic from any direction, i.e. from the front, back or from the side of the wrong-way traffic vehicle, as long as the alertness effect of the driver of the wrong-way traffic vehicle can be obtained. Hence, said second light can propagate in the same direction as the travel direction of the wrong-way traffic and can then be observed and cause glare to the driver of the wrong-way traffic vehicle, for example, via the back mirror of the wrong-way traffic vehicle. Alternatively said second light can propagate in a direction opposite to the travel direction of the wrong-way traffic vehicle and then the second light is intended to directly imping on the eyes of the driver of the wrong- way traffic vehicle. Additionally or alternatively to a mere providing of glare light, other features may be provided to the second light, which will be elucidated later. In yet a further aspect, the invention also provides a street provided with the street lighting system

comprising one or more street light elements as defined herein.

With such system, no additional infrastructure may be necessary as existing lighting positions along a street can be applied. It may even be possible to replace existing lighting units in existing street light elements with lighting units as defined herein. Further, the invention allows providing the glare light on a single, but also on a plurality of positions along a street. Hence, in this way safety can be improved in a relatively easy way. Further, the glare light may - in an intuitive way - teach a driver that a wrong direction has been chosen, as the glare light may have the same effect as a headlight of a driver driving in the opposite direction may be perceived by the wrong-way driver.

The street lighting system especially comprises one or more street light elements. Here, the term "street light element" may refer to a street light, a light pole, a lamppost, a street lamp, a light standard, or a lamp standard, and in general to any raised source of light, especially on the edge of a street. The term "street light element" may also refer to a lighting unit that is integrated in road barriers, tunnels, including tunnel walls or tunnel ceilings that are used for street lighting. Herein, a plurality of poles with catenary lighting is indicated as a specific embodiment of a plurality of street light elements. The street light element may be configured at an edge of a street, such as a roadside, but may also be configured at median of a highway. The street light element may also be configured over a street. Herein, the term "street" may refer to a road, a track, a path, a way, a motorway, a highway, etc.. The term street may refer to a street within the built environment or between built environments, etc.. In general, the street lighting system will include a plurality of street light elements. The term "street" may also refer to a ramp or exit to e.g. a highway or road, etc.. In specific embodiments, the term "street" may also refer to one or more of a parking lot, a pedestrian path, a cycle path, etc.. In yet further specific embodiments, the term "street" may also refer to a waterway (with the invention especially being used warn a ship at the wrong place or moving in the wrong direction). The term "street" may also refer to a part of a street, such as one or more lanes of a street, or a part of one or more lanes.

Here, the system is especially described in relation to its use, i.e. described as being arranged and installed at a street for use as street lighting. However, the invention is not limited to a configuration in use only. For instance, the invention also provides the street light elements per se, i.e. not yet installed but configured to be installed at a street.

Each street light element comprises a lighting unit configured for lighting a street with lighting unit light. Especially, such street light element is configured to provide (in use) street light that complies with street light regulations defined by the relevant national government or international organization (where the street lighting system is applied). An example of a regulation is European Standard EN 13201 (CEN).

Further, at least one street light element, more especially at least one lighting unit, of the street lighting system comprises a second lighting functionality. This functionality allows the system, or more especially the at least one lighting unit, to provide second light. This second light can be used as glare light to warn a wrong way driver. The second light can be generated by a separate light source comprised by the lighting unit and/or by redirecting (at least) part of the lighting unit light. Therefore, the lighting unit comprises one or more of (i) a redirection element controlled by said control system and configured to redirect at least part of the lighting unit light (for providing second light controlled by said control system) and (ii) an additional light source controlled by said control system for providing second light controlled by said control system. Hence, in a first embodiment the at least one lighting unit having said second lighting functionality comprises said redirection element controlled by said control system and (the at least one lighting unit is) configured to redirect at least part of the lighting unit light for providing second light controlled by said control system. Especially, the redirection element comprises one or more of adaptable optics and a movable reflector. Alternatively or additionally, in a second embodiment the at least one lighting unit having said second lighting functionality comprises said additional light source controlled by said control system for providing second light controlled by said control system. Adaptable optics may e.g.

include one or more of a movable mirror and or movable polarizers for block or passing light. Further, in embodiments LEDs of a LED array can be controlled to illuminate specific regions. Also such embodiments may be used to create glare at the desired angles and locations. The terms "redirection element" or "additional light source" may also refer to a plurality of redirection element or additional light source, respectively. Hence, in such embodiments it may be possible to provide second light in different directions, for instance in embodiments in response to a sensor signal of the sensor(s).

As indicated above, the street lighting system may comprise a control system. The control system may - amongst others - be configured for controlling the lighting unit(s) (with second lighting functionality). When the system comprises a plurality of street light elements, only those street light element(s) comprising lighting units with second lighting functionality may be controlled by such control system. The control system may include a master control system configured to control slave control systems in the street light elements. When the system comprises a plurality of street light elements, only those street light element comprising lighting units with second lighting functionality may comprise (slave) control systems. One of them, or external of the street light elements, a master control system may be configured. Hence, in embodiments at least one street light element comprises a control system.

Further, as indicated above in embodiments at least one street light element comprises a sensor. In embodiments, the street light element comprising the lighting unit with second lighting functionality also comprises a sensor. However, in other embodiments one or more other street light elements comprise such sensor. Also in this way, sensors detecting wrong-way traffic can be used to trigger street light elements ahead of the wrong- way traffic to switch the second light on. Hence, in embodiments the street lighting system comprises a plurality of street light elements, each comprising said sensor. For instance, the street lighting system comprises a plurality of street light elements comprising lighting units (each) further comprising said second lighting functionality, wherein the street lighting system is configured to provide said second light by one or more of said lighting units (further comprising said second lighting functionality), especially in dependence of the position and estimated speed of the wrong- way traffic. With one or more sensors, the system may determine position and estimated speed (of the wrong-way traffic) and decide which street light element should provide the second light.

The control system and the sensor are configured to detect wrong- way traffic. Such systems are known in the art. For instance, the sensor comprises one or more of a microphone, an optical sensor, a magnetic field sensor (e.g. an electronic compass using the changes in the magnetic field), a radar, and a RF sensor. The optical sensor may in embodiments include a camera. Many highways or motorways are equipped with cameras for traffic surveillance. Further, the sensor may include a mobile phone sensor (configured to detect mobile phone signals). For instance, nearly any driver nowadays has a mobile phone on board. The signal may be detected and be used to determine wrong way driving. Further, the sensor may include an internet signal sensor. Many vehicles are nowadays connected with the internet during driving. This internet signal may be detected and be used to determine wrong way driving. The sensor, or a plurality of sensors, may be used to detect a (moving) vehicle. The control system may based thereon determine speed and direction. Further, the control system may possess a memory with information about the right (or correct) traffic direction. Based hereon, the system may determine ("sense") whether traffic is wrong-way traffic. If wrong-way traffic is determined, one or more street light elements may be triggered by the street lighting system to provide second light. The additional light source is configured such and/or the redirection element is configured such, that the second light is provided in a direction opposite of the right driving direction. Hence, the second light may have an optical axis that has a component direction opposite of the right driving direction. Therefore, the street lighting system is configured to provide said second light in a direction of the wrong- way traffic in dependence of wrong-way traffic being sensed. The term "sensor" may also refer to a plurality of (different) sensors. Hence, in embodiments whether or not second light is provided is controlled by the control system.

When right-way traffic or wrong-way traffic is defined, especially traffic in a direction anti-parallel to the direction of right-way traffic or wrong-way traffic may be defined wrong-way traffic or right-way traffic, respectively.

The lighting unit may be configured such that lighting unit light may be redirected while maintaining the lighting unit light provided to the street in compliance with the conditions or regulations for street lighting. Often, street lights are over qualified. For instance, street lights may have a variety of dimming options to adapt the light to specific needs while minimizing energy consumption. Hence, a redirection of part of the light may not have an undesired influence on the lighting unit light (street lighting). Of course, when using an additional light source, this may have no impact at all on the lighting unit light.

Additionally or alternatively to a mere providing of glare light, also other features may be provided to the second light. This may assist in warning a driver that a wrong direction is chosen. In embodiments the street lighting system is configured to provide a frequency modulation to the second light having a frequency selected from a range perceivable by a human observer. In embodiments the street lighting system is configured to provide a frequency modulation to the second light having a frequency selected from the range of 0.1-50 Hz, such as 0.1-20 Hz. When more than one street light element comprises a lighting unit with second functionality, the modulation may be controlled in dependence of the distance to the wrong-way traffic. For instance, the larger the distance, the higher the frequency. This may also aid in warning the wrong-way driver. Alternatively or additionally, the street lighting system is configured to provide second light having a color or color temperature different from the lighting unit light. For instance, a color filter can be used and/or the additional light source may be configured to provide the second light having a color or color temperature different from the lighting unit light.

Higher correlated color temperature (CCT) sources are usually perceived as brighter. Higher CCT sources may make outdoor areas appear to be more brightly lighted than illuminance and luminance measurements may suggest. Hence, a higher color temperature may provide or enhance a glare effect. In yet further embodiments, the "color coding" could be similar to traffic lights. Going from distant to close to the critical section it could change from normal, to orange to red.

In embodiments, additional to or instead of a frequency modulation the amplitude may be modulated. Hence, the intensity may be frequency and/or amplitude modulated. Hence, with e.g. a frequency of 0.1-50 Hz, such as 0.2-02 Hz, the second light may be switch on and off, or may be varied in intensity.

Hence, the glare effect may be switched on and off with the above indicated frequency or the glare effect may undergo a modulation with such frequency (i.e. strong and weak), for instance a modulation between a m% intensity and a n% intensity, wherein n is smaller than m, and wherein m and m are selected from the range of 0-100% of the maximum intensity of the lighting unit, such as m% being 100%, an n% being in the range of 95% of the maximum intensity and equal to or larger than 0% of the maximum intensity (such as in embodiments an intensity larger than off; e.g. n is e.g. 60%, or 40%, or 20%>).

In some instances, whether traffic is wrong-way traffic may depend upon the type of traffic. For instance, one-way streets may be one-way for motorized vehicles, but not for cyclists. Or, one-way streets may be one-way for heavy traffic, but not for cars used for carriage of passengers. Therefore, in embodiments the control system and the sensor are configured to sense a predetermined type of wrong-way traffic. In this way, the system may only provide second light when the predetermined type of wrong-way traffic is sensed. Especially, the control system and the sensor are configured to sense a predetermined type of wrong-way traffic selected from the group consisting of motor vehicles with less than four wheels, power-driven vehicles having at least four wheels and used for the carriage of passengers, power-driven vehicles having at least four wheels and used for the carriage of goods, (semi-)trailers, special purpose vehicles, off-road vehicles, and agricultural and forestry tractors. For instance, the traffic may be classified according to "Council Directive 70/156/EEC of 6 February 1970 on the approximation of the laws of the Member States relating to the type-approval of motor vehicles and their trailers ^' ", which includes:

- Category M: Motor vehicles having at least four wheels, or having three wheels when the maximum weight exceeds 1 metric ton, and used for the carriage of passengers.

- Category Ml : Vehicles used for the carriage of passengers and comprising no more than eight seats in addition to the driver's seat.

- Category M2: Vehicles used for the carriage of passengers, comprising more than eight seats in addition to the driver's seat, and having a maximum weight not exceeding 5 metric tons.

- Category M3 : Vehicles used for the carriage of passengers, comprising more than eight seats in addition to the driver's seat, and having a maximum weight exceeding 5 metric tons.

- Category N: Motor vehicles having at least four wheels, or having three wheels when the maximum weight exceeds 1 metric ton, and used for the carriage of goods.

- Category Nl : Vehicles used for the carriage of goods and having a maximum weight not exceeding 3 75 metric tons.

- Category N2: Vehicles used for the carriage of goods and having a maximum weight exceeding 3 75 but not exceeding 12 metric tons.

- Category N3 : Vehicles used for the carriage of goods and having a maximum weight exceeding 12 metric tons. - Category O: Trailers (including semi-trailers) - Category 01 : Trailers with a maximum weight not exceeding 0 775 metric ton.

- Category 02: Trailers with a maximum weight exceeding 0 775 metric ton but not exceeding 3 75 metric tons.

- Category 03: Trailers with a maximum weight exceeding 3 75 but not exceeding 10 metric tons.

- Category 04: Trailers with a maximum weight exceeding 10 metric tons.

Further, the system may be configured to distinguish between motorized and non-motorized traffic. Yet further, the system may be configured to control the second light in dependence of the presence of different types of traffic travelling in the same direction, of which at least one travels in the right direction and at least one travels in the wrong-way. In such embodiments the street lighting system may further configured to provide said second light in a direction of the wrong-way traffic in dependence of wrong-way traffic being sensed and in dependence of traffic being sensed propagating in the same direction but not being classified by the control system as wrong-way traffic. For instance, when both types of traffic being sensed, the system may be configured not to give a warning in the form of the second light, or to adapt the second light. For instance, the color or color temperature of second light, or the modulation may be adapted in dependence both wrong-way traffic and right way traffic travelling in the same direction being sensed. Alternatively or additionally, the system may control different street light elements in dependence of wrong-way traffic and right way traffic travelling in the same direction being sensed, for instance such that when the two traffics are at the same position, glare may be minimized (in view of the right-way traffic), whereas when the two traffics are at different positions, possible glare for right way traffic is minimized, whereas for wrong-way traffic the second light is provided.

Hence, the term "wrong-way traffic" may especially refer to vehicles that perform "wrong way driving". Wrong-way driving, here is intended to mean vehicular movement along a travel lane in a direction opposing the legal flow of traffic on high-speed divided highways or access ramps (it does not include wrong-way movements that result from median crossover encroachments). However, in other embodiments the term "wrong- way traffic" may also refer to non-motorized vehicles, or even to pedestrians. The definition of wrong-way traffic thus may refer to traffic being on a part of the street or traveling in a direction on the street which is not intended, especially not intended by relevant authorities. The definition of wrong way traffic may result in e.g. a permanent setting of the street lighting system, such that the second light is always provided in the same direction. However, the definition of wrong way traffic may also depend upon time or situation, and e.g. be controlled remote.

When a street is wet or partly covered with ice or snow reflections of light may occur. In embodiments, the system may take into account such effects and use these to its advantage to provide the second light to the wrong-way traffic. Hence, in embodiments the control system and the sensor are configured to sense reflectance of the street, and the street lighting system is configured to provide said second light in dependence of said reflectance. Here, phrases like "control system and the sensor are configured to sense" and similar phrases are applied, to indicate that the sensor may measure something and provide a corresponding sensor signal and the control system may interpret the sensor signal and thereby sense or determine e.g. wrong-way traffic, reflectance of the street, right way traffic, etc.. When wrong way traffic is determined (by the control system and sensor), the second light may be provided.

As also indicated above, there may be situations or places where wrong way and right way are dependent upon the time or situation. For instance, the traffic direction may depend upon the time of the day with different directions during rush hours than during periods outside rush hours. One may also consider emergency lanes, etc.. Hence, in embodiments the street lighting system may be remote controlled, allowing a remote definition of wrong way and/or right way. In this way, the control system can be updated to the required situation. Optionally, remote control of the system may also be used to redefine the type of traffic that can be considered wrong-way traffic (see also above).

Alternatively or additionally, the system may be a self-learning system. For instance, after sensing a plurality of vehicles, all driving the same direction, and no vehicle driving another direction, the control system may determine that the (part of the) street is a one-way street. Thereafter, the system may start providing second light when wrong-way traffic is determined. To this end, the street lighting system may have the functionality of a learning stage, wherein the system learns the directions of wrong way and right way. Yet further, the learning stage may be triggered from external (remote control, see also above). Hence, in embodiments the control system is a self-learning control system configured to learn during a learning stage what is right way traffic and what wrong- way traffic is, and configured to provide said second light in a direction of the wrong-way traffic in dependence of wrong-way traffic being sensed after said learning stage. Such learning stage may be a one-time only learning. However, such learning stage may also periodically be applied. Therefore, in embodiments the learning stage is periodically repeated and/or wherein the learning stage can be controlled remote. Once the system has learned what right-way traffic is, any traffic in another direction, especially anti-parallel thereto may be considered wrong- way traffic.

The street lighting system may in embodiments be used to configure remotely the wrong way driving direction or activate the glare effect based on detected road block to re-route traffic. Further, also road layout information and changes therein can be obtained from GIS (geographic information systems) databases or cloud services, like Google maps.

In instances, such as due to an accident, it may be necessary to block a street. To redirect traffic, a control centre may control the street lighting system (on a relevant segment of the street) to introduce the second light (produce glare), such as to signal road users. Under normal conditions, however, the street may be free to enter. Hence, in embodiments the defmtion of "wrong-way" may depend upon time and situation, and may be controlled. Likewise, in embodiments the direction to which the second light is provided may be controlled.

In further aspects, glare may be used to warn for dangerous street conditions due to e.g. icing. For instance, glare may be used to guide traffic to use a certain lane or to not use a certain other lane.

In a further aspect, the invention provides a (static) street light, or a street lighting system comprising a plurality of street lights, that is (are) configured to produce glare in the wrong driving detection. For instance, the invention also provides a street lighting system comprising one or more street light elements, wherein each street light element comprises a lighting unit configured for lighting a street with lighting unit light, wherein the street lighting system is further configured to provide said second light in a direction of the wrong-way traffic. Hence, the invention also provides a street lighting system comprising one or more street light elements, wherein each street light element comprises a lighting unit for lighting a street with lighting unit light, wherein at least one lighting unit further comprises a second lighting functionality for providing second light in a direction of wrong-way traffic can be used to impose glare (with the second light) to the wrong-way traffic. Especially, such embodiments may be of relevance for highways, wherein the travelling direction is in general fixed (in one way). Such street light element may optionally comprise a redirection element.

In alternative embodiments, instead of a redirection element an element is applied that changes the color or color temperature of the second light or an element is used that provides second light with another color or color temperature than the first light. The term "controlling" especially refers to determining the behavior or supervising the running of an element. Hence, herein "controlling" may e.g. refer to imposing behavior to the additional light source or redirection element, etc..

The lighting unit comprises at least a single light source. The term "light source" may also relate to a plurality of light sources, such as 2-200 (solid state) LED light sources. Hence, the term LED may also refer to a plurality of LEDs. The lighting unit is especially solid state light based, such as based on LEDs. This may apply to the basic function of providing lighting unit light for street lighting, but also for the light source for the second functionality (when an additional light source is applied).

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the invention will now be described, by way of example only, with reference to the accompanying schematic drawings in which corresponding reference symbols indicate corresponding parts, and in which:

Fig.l schematically depicts an embodiment of the system in a configuration in use; Figs. 2a-2b schematically depict some variants; and

Fig. 3 schematically depicts a further embodiment.

The schematic drawings are not necessarily on scale. DETAILED DESCRIPTION OF THE EMBODIMENTS

Fig. 1 schematically depicts an embodiment of a street lighting system 10 comprising one or more street light elements 100. Here, by way of example only a single street light element 100, here a pole, is depicted. The traffic signs, indicated with references 2, are depicted for indicating that this street, indicated with reference 1, is a one way street ((motorized) vehicles are only allowed to drive to the right (right way), not to the left (wrong way). Hence, the vehicle 118 is driving the wrong way. The street lighting system 10 is configured to provide during use on the street 1 where the street lighting system 10 is implemented (for the street lighting).

The street light element 100 comprises a lighting unit 110 configured for lighting a street with lighting unit light 111. The street lighting system 10 comprises a control system 130, especially configured to control the lighting unit 110. Here, the control system is comprised by the street light element 100. Note that optionally the control system 130 may be remote controlled. The street light element 100 further comprises - in this schematically depicted embodiment - a sensor 140. By way of example, it is schematically depicted that the sensor 140 comprises a radar. The control system 130 and the sensor 140 are configured to detect wrong-way traffic, which is here the case.

The lighting unit 110 further comprises a second lighting functionality, i.e. for providing second light 112. The street lighting system 10 is configured to provide said second light 112 in a direction of the wrong-way traffic 118 in dependence of wrong-way traffic being sensed, i.e. in the situation shown in Figure 1 the second light (is issued and) propagates in a direction which is essentially or substantially opposite to the travel (or propagation) direction 119 of the wrong-way traffic, or in other words, the second light and the wrong-way traffic propagate in essentially or substantially mutually opposite directions. This second light can also be indicated as glare light, which attends the driver of the vehicle that a wrong way is chosen. The second light 112 is also controlled by said control system 130. To provide second light 112, the lighting unit 110 comprises a redirection element (controlled by said control system 130 and configured to redirect at least part of the lighting unit light 111) or an additional light source (controlled by said control system 130).

Here, by way of example a puddle of water 3 is on the street. In embodiments, the control system and the sensor are configured to sense reflectance of the street. The street lighting system is configured to provide said second light in dependence of said reflectance. Such reflectance may be used to let the second light further propagate, as also second light 112 after reflection may have the glare effect.

As can be seen in Fig. 1, the lighting unit light 111 has an optical axis 111a, which is in this embodiment about perpendicular with the street 1. Further the second light has an optical axis 112a. Especially, the optical axis 112a of the second light is not parallel to the optical axis of the lighting 111a. Even more especially, the optical axis 112a of the second light 112 especially has an angle β with the street in the range of at about 0-70°, such as 5-30°. With such angles, glare lighting may be perceived by a wrong-way driver. In this way, the invention provides glare-based signaling system for intelligent lighting for warning wrong-way drivers. Hence, the lighting unit may especially be configured to provide lighting unit light having an optical axis 111a and second light having an optical axis 112a having a mutual angle a in the range of 20-85°, especially 60-85°. Optionally, the direction of the second light may be controllable, e.g. with the redirection element of by using additional light sources that are configured under mutual (optical axis) angles and which are

independently controllable. In general, light having an optical axis with an angle Θ between about 60-90° with a vertical (indicated with V) is considered light having a glare effect. In embodiments, based on a measured location of the wrong-way driver, a light profile could be adapted such to dynamically create to maximum glare effect substantially only at the location of the wrong-way driver. This could be realized be controlling the angle (i.e. β or Θ (which are interrelated)) and additionally also limit the light effect to area surrounding the driver (like a spot light).

Figs. 2a and 2b schematically depict two embodiments to generate the second light 112. In Fig. 2a, the lighting unit 110 (having said second lighting functionality) comprises a redirection element 150. This redirection element is also controlled by said the control system (not shown). The redirection element 150 is configured to redirect at least part of the lighting unit light 111 for providing second light 112 (controlled by said control system). Reference 105 indicates a light source. The same light source 105 is used for street lighting, i.e. lighting unit light 111 and second light or glare light. The redirection element 150 may e.g. be a movable reflector 151. Fig. 2b schematically depicts an embodiment wherein the lighting unit 110 (having said second lighting functionality) comprises said additional light source 210, also controlled by the control system (not shown) for providing second light 112 (controlled by said control system).

By way of example, Fig. 2b schematically depicts an optical filter 270 (which may also be used in the embodiment of Fig. 2a), and which may be used to provide the second light 112 another spectral distribution than the lighting unit light 111. Similar effects may be realized with using LEDs with different color characteristics. It could be additional LEDs illuminating the specific glare angles with another color spectrum. This could also be implemented by changing the colors emitted by RGB-LEDs illuminating the specific glare angles while keeping the colors emitted by the other RGB-LEDs unchanged, etc..

Note that in in Figs. l-2b the second light 112 is directed in one direction. However, street light elements as described herein may also have the functionality to provide second light in two or more directions, especially with the direction of the second light in dependence of the definition of wrong way, which may vary with time or situation. The direction of the light is especially parallel to the optical axis of the light (and in a direction away of the respective light source generating the light).

Fig. 3 schematically depicts an embodiment of the street lighting system 10 comprising a plurality of street light elements 100 comprising lighting units 110 of which a plurality further comprise said second lighting functionality. Further, the street lighting system 10 comprises a plurality of street light elements 100, each comprising said sensor 140. Hence, the street lighting system comprises a plurality of sensors 140; optionally the plurality of sensors may comprise different types of sensors. Reference 1300 indicates a master control system which may be included in one of the street light elements 100 of which may be configured external of these street light elements. The master control system 1300 may control all control systems 130 of each street light element 100. Note that by way of example not all street light elements 100 comprise the second functionality and a control system 130. Here, by way of example one street light element 100 does not have such second

functionality, but nevertheless includes a sensor 130. This sensor may also be used for sensing wrong- way traffic.

Hence, in this invention, we propose glare-based light signaling to alert road users driving on the wrong way. The solution especially uses sensorial information to detect traffic entering from the wrong direction and change the light profile such that the road user will experience glare. The glare level can be realized by adaptable optics or activation of LEDs directed at the road with small inclination angles. The invention comprises in embodiments the following building blocks:

1. Sensor- integrated lighting network infrastructure with one or more light poles having one or more sensors (sensor-hub) integrated in each pole

2. Sensor monitoring traffic parameters:

a. Type of traffic

b. Speed of traffic

c. Direction of traffic

3. Luminaire with glare control means by adaptable optics, activation of additional LEDs or moveable reflector

4. A priori knowledge about allowed road usage and/or optionally the allowed road usage can be learned from traffic patterns observed by a sensor

One embodiment is an intelligent luminaire placed along a road with a one- way driving direction and configure the luminaire as such. The installer can use a hardware switch or a software tool to give in the allowed driving direction. The wrong way driving can be detected by a sensor that extracts the driving direction of vehicles. The luminaire will adapt its optics when a car driving in the wrong way based is detected. The wrong driving signal can be propagated through the lighting network to other luminaires along the road to also adapt their optics top create a warning signal. The sensor could be embedded only in the luminaire at the entrance of the road or in every luminaire along the road.

The wrong way driving could be detected by one or a combination of the following sensors:

• Microphone or microphone array • Camera system with video analytics

• Electronic compass using the changes in the magnetic field

• Radar sensor

• Antenna monitoring RF signals from vehicles

Furthermore, the sensor module can be used to classify the vehicle type. In some cases, the wrong driving direction is only for certain vehicle types (e.g. bicycles). Changing the light profile to create glare for warning the road user could also be realized by mechanical means, activation of LEDs with a different optics, or an additional light source. Similar concept could be applied to enforcement of speed limits. In case of overspeeding the glare will be used to inform the road user.

Hence, as indicated above in further aspects the sensing may be optional, such as in embodiments where the road usage is predefined, like e.g. highway exits. In such embodiments, the glare effect may be static or only activated at presence of wrong driving traffic.

Other implementations may include the street light element to adapt the glare effect based on the measured location of the wrong-way traffic. In case multiple street light elements, such as poles, are used to create the glare effect each street light element, such as pole, could adapt it light settings such to create an effect observed at the wrong-way traffic location. When a certain traffic type is not allowed to enter a street, these street light elements, such as poles, can be selected to create the glare effect while not activating the glare effect with street light element, such as poles, that could disturb other road users.

The term "substantially" herein, such as in "substantially all light" or in "substantially consists", will be understood by the person skilled in the art. The term

"substantially" may also include embodiments with "entirely", "completely", "all", etc. Hence, in embodiments the adjective substantially may also be removed. Where applicable, the term "substantially" may also relate to 90% or higher, such as 95% or higher, especially 99% or higher, even more especially 99.5% or higher, including 100%. The term "comprise" includes also embodiments wherein the term "comprises" means "consists of. The term "and/or" especially relates to one or more of the items mentioned before and after "and/or". For instance, a phrase "item 1 and/or item 2" and similar phrases may relate to one or more of item 1 and item 2. The term "comprising" may in an embodiment refer to "consisting of but may in another embodiment also refer to "containing at least the defined species and optionally one or more other species". Furthermore, the terms first, second, third and the like in the description and in the claims, are used for distinguishing between similar elements and not necessarily for describing a sequential or chronological order. It is to be understood that the terms so used are interchangeable under appropriate circumstances and that the embodiments of the invention described herein are capable of operation in other sequences than described or illustrated herein.

The devices herein are amongst others described during operation. As will be clear to the person skilled in the art, the invention is not limited to methods of operation or devices in operation.

It should be noted that the above-mentioned embodiments illustrate rather than limit the invention, and that those skilled in the art will be able to design many alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. Use of the verb "to comprise" and its conjugations does not exclude the presence of elements or steps other than those stated in a claim. The article "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. The invention may be implemented by means of hardware comprising several distinct elements, and by means of a suitably programmed computer. In the device claim enumerating several means, several of these means may be embodied by one and the same item of hardware. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage.

The invention further applies to a device comprising one or more of the characterizing features described in the description and/or shown in the attached drawings. The invention further pertains to a method or process comprising one or more of the characterizing features described in the description and/or shown in the attached drawings.

The various aspects discussed in this patent can be combined in order to provide additional advantages. Further, the person skilled in the art will understand that embodiments can be combined, and that also more than two embodiments can be combined. Furthermore, some of the features can form the basis for one or more divisional applications.