Abstract:
A variable lighting system (“VLS”) for optimizing object visibility at night by setting a base level of lighting, adding a variable light to that base level of lighting, and a synchronizing the timing and sequence of the base level of lighting and the variable lighting. The variable lighting system varies light by intensity, color, direction, or a combination thereof. The variable lighting system also optionally includes a detector for detecting motion, noise, and other occurrences. The variable lighting system can be implemented as a fixed lighting source, a movable lighting source, or a vehicle mounted lighting source. The VLS improves visibility at night for viewers or motorists thereby reducing accidents and damage costs. The VLS saves energy and improves the environment and enhances quality of life by reducing light pollution and light trespass.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     1. Technical Field  
         [0002]     This invention generally relates to lighting systems. Particularly, the invention relates to lighting systems for optimizing night visibility.  
         [0003]     2. Description of Related Art  
         [0004]     Night visibility is a well known concern of many individuals and is particularly a safety concern for night driving. As a result, artificial lighting such as street lights have been placed on roadways and in parking lots to improve night visibility for motorists. However, artificial lighting is not always sufficient for motorists and individuals so alternatives for improving night visibility have been established.  
         [0005]     For example, one method for designing fixed roadway lighting promulgated by the American Standards Institute (ANSI) and Illuminating Engineering Society of North America (IESNA) is termed “Small Target Visibility” and is a method for maximizing the visibility of small (7 inch square) targets on a roadway. However, with this method all objects are still not detectable because there is not enough contrast between the object and background.  
         [0006]     There is a desire to optimize headlamp and fixed roadway lighting system interactions to improve visibility. Other systems include aesthetic “under vehicle” lighting as well as variably aimed headlamps wherein both provide some assistance in detecting roadway hazards. These existing lighting systems, while beneficial, use large amounts of power and hence are costly. There is a need for a lighting system that further improves visibility at night on roadways and other artificially lit areas while also being cost effective.  
       SUMMARY OF THE INVENTION  
       [0007]     The invention described below is a variable lighting system (“VLS”) for optimizing object visibility at night. The VLS comprises a base lighting element, a variable lighting element, and a master synchronizer for synchronizing the timing and sequence of the base level lighting and the variable lighting. The VLS sets the base level of lighting, adds the variable light to the base level of lighting, and synchronizes the timing and sequence of the lighting elements. The VLS varies light intensity, color, and direction and optionally includes a detector for detecting motion, noise, or other occurrences.  
         [0008]     The VLS can be implemented as a fixed lighting source, a movable lighting source, or a vehicle mounted lighting source. It improves visibility at night for all viewers, particularly bicycle riders, pedestrians, and motorists thereby reducing accidents and damage costs and saving lives. Furthermore when compared to known lighting systems, the VLS saves energy, improves the environment, and enhances quality of life by reducing light pollution and light trespass.  
     
    
     BRIEF DESCRIPTION OF DRAWINGS  
       [0009]     The novel features believed characteristic of the invention are set forth in the appended claims. The invention itself, however, as well as a preferred mode of use, further objectives and advantages thereof, will be best understood by reference to the following detailed description of illustrative embodiments when read in conjunction with the accompanying drawings, wherein:  
         [0010]      FIG. 1  is a perspective view illustrating the variable lighting system of the present invention;  
         [0011]      FIG. 2  is a flow chart depicting the steps involved in synchronizing the clock of the present invention; and  
         [0012]      FIG. 3  is a flow chart depicting the steps involved in synchronizing the timing sequence of the present invention.  
     
    
     DETAILED DESCRIPTION  
       [0013]     In the descriptions that follow, like parts are marked throughout the specification and drawings with the same numerals, respectively. The drawing figures are not necessarily drawn to scale and certain figures may be shown in exaggerated or generalized form in the interest of clarity and conciseness.  
         [0014]      FIG. 1  depicts a variable lighting system (“VLS”) of the present invention. VLS  102  includes base lighting element  104 , variable lighting element  108 , and may contain synchronizer  110 . The illumination range of base element  104  can range from zero to 100 million candle power and may be variable. Preferably the minimum illumination level is the lowest illumination detectable by the human eye based on the surrounding environment and the maximum illumination level is the maximum amount of illumination that would be safe for the surrounding environment. Base lighting element  104  can be configured to consist of light energy in one, a portion of, or all of the visible wavelengths (anything from mono-chromatic to white light). In addition to the illumination from base lighting element  104 , if any, variable lighting element  108  adds varying amounts of illumination, color, and/or light direction.  
         [0015]     The illumination from variable lighting element  108  can be varied in any given direction. The direction of illumination may be in one direction, such as north, two directions such as north-south, or more such as north-east-south-west directions. For example, to vary the direction of illumination when using one light source and two directions, the variability is provided by an increase in the light intensity emitted by a source in the northward direction, then a decrease in the intensity emitted northward with an increase in the intensity emitted in the southward direction, then a decrease in the intensity emitted southward which is followed by a repeat of the cycle again piecewise-continuously. The cycle frequency itself may be at a steady interval, such as every 0.5 seconds, or variable and can be any frequency greater than about 1/250th of a second, or the smallest amount of flicker the eye can detect. Preferably, the cycle frequency is about 0.5 seconds.  
         [0016]     To vary the illumination from one illumination source in more than two directions, for example, north-east-south-west, the light intensity emitted by the source in the northward direction is increased; then the intensity in the northward direction is decreased and the intensity in the eastward direction is increased; then the intensity in the eastward direction is decreased and the intensity in the southward direction is increased; then the intensity in the southward direction is decreased and the intensity in the westward direction is increased; then the intensity in the westward direction is decreased and the intensity emitted northward is increased; and the cycle is then repeated piecewise-continuously. The cycle does not need to be continuously clockwise or counterclockwise and may be in any order or sequence and may be variable. The length of the “on,” “off,” “increase,” or “decrease” cycle of any direction need not be the same as other directions “on,” “off,” “increase,” or “decrease” cycle times and may also be variable in any and all directions. The cycle frequency itself may be at a steady interval, such as every 0.5 seconds, or variable and can be any frequency greater than about 1/250th second, or the amount of flicker the eye can detect. Preferably, the cycle frequency is about 0.5 seconds.  
         [0017]     Variable lighting element  108  can also provide illumination using a variable color in a given direction. The light emitted in a given direction may be any color or a combination of colors. For example, red light may be emitted northward, then dimmed and then green light increasingly emitted northward as the red light is dimmed and then the red light increasingly emitted northward as the green light is dimmed. Also, similar light patterns may be emitted southward either at the same time or at a subsequent time period synchronized with the light that is being emitted in another direction. For example, red light may be emitted northward while green light is emitted southward. Then the northward red light is dimmed and green light is increasingly emitted northward while the green southward light is dimmed and the red light is increasingly emitted southward. The variable lighting system in this example will provide a varying color and intensity contrast of red and green. This will provide better contrast compared to the existing method of a simple static intensity contrast, thereby increasing visibility. The color emitted north and south is typically not the same color at the same time.  
         [0018]     A similar cycle may occur if more than two directions and/or more than two colors are used. For example, a red light may be emitted northward, a blue light eastward, a green light southward, and a yellow light westward. Then the red light is dimmed and the blue light is increasingly emitted northward while the blue eastward light is dimmed, the green light is increasingly emitted eastward while the green southward light is dimmed, the yellow light is increasingly emitted southward while the yellow westward light is dimmed, and the red light is increasingly emitted westward. The general cycle is repeated piecewise-continuously. The cycle does not need to be continuously clockwise or counterclockwise and may be in any order or sequence and may be variable. The length of the “on,” “off,” “increase,” or “decrease” cycle of any direction need not be the same as other directions “on,” “off,” “increase,” or “decrease” cycle times and may also be variable. The cycle frequency itself may be at a steady interval, such as every 0.5 seconds, or variable and can be any frequency greater than approximately 1/250th second, or the amount of flicker the eye can detect. Preferably, the cycle frequency is about 0.5 seconds. Two, four, six, or eight directions is optimal.  
         [0019]     If more than one VLS  102  is used, then each VLS  102  also comprises synchronizer  110 . Synchronizer  110  coordinates the timing and sequence of all VLS  102  light emitting components such as base lighting element  104  and variable lighting element  108 . Synchronizer  110  provides a timing coordination signal so that directional variability for each color and intensity from each element may work together in harmony so that each lighting element of base lighting element  104  and variable lighting element  108  will increase intensity in the same color and/or direction at the same time and each subsequent action will occur simultaneously from each VLS  102 .  
         [0020]     Synchronizer  110  may generate timing signals to coordinate the timing and sequence of the lighting intensity, color, and direction of illumination from base lighting element  104  and variable lighting element  108 . Each synchronizer  110  contains a clock that is synchronized with a standard timing device or another synchronizer  110  in the area. The standard timing device may be any standard timing device known in the art or may be the AC sine wave located on every power line and generated from the electrical plant supplying electricity to the area. The sequence of the lighting intensity, color, and direction of illumination from base lighting element  104  and variable lighting element  108  is preprogrammed in each VLS  102  and VLS  103  and may be hardwired or rewritable.  
         [0021]     The sine wave may also be used to synchronize the timing or clocks of other elements besides the lighting. However, in the preferred embodiment, the synchronizer is used to synchronize the lighting. To synchronize the clocks, the frequency of the sine wave is measured used to create a standard of time. Any other device that can access the sine wave can use the sine wave to create the same standard of time.  
         [0022]     Synchronizer  110  emits a wireless synchronization signal to objects such as vehicles or other components not connected to the standard timing device so that any VLS  102  that cannot access the standard timing device can be synchronized with any other VLS  102  in the vicinity. In addition, synchronizer  110  emits a timing signal that includes the sequence of the lighting intensity, color, and direction of illumination from base lighting element  104  and variable lighting element  108 . Also, all synchronizers  110  are equipped with priority codes so that one synchronizer acts as a master synchronizer for a given area and the wireless synchronization signal and timing signal are used by all the VLS  102  in the area.  
         [0023]     VLS  102  may be implemented as fixed lighting sources or a mobile lighting source. Fixed lighting sources include lights on street light poles, in parking lots or on buildings. Mobile VLS  103  includes any VLS mounted on mobile source such as vehicle  112 . Vehicle  112  mounted VLS  103  includes at least one base lighting element  104  and at least one variable lighting element  108 . One base lighting element  104  and/or one variable lighting element  108  may be mounted on the front of vehicle  112  similar to headlamps. The at least one base lighting element  104  and at least one variable lighting element  108  may be mounted on the side and/or rear of vehicle  112 . A mobile VLS  103  is the same as a fixed VLS  102  except the mobile VLS  103  is on a mobile source and there may be more than one base lighting element  104  and more than one variable lighting element  108 .  
         [0024]     The intensity of a side or rear mounted base lighting element  104  and variable lighting element  108  may be almost any intensity that is safe for the environment it is being used in. Compared to headlamps which illuminate only in the front, but not necessarily toward the roadway, the illumination from the side or rear mounted base lighting element  104  and variable lighting element  108  may be emitted toward the roadway or any other direction away from the vehicle and may be variable. For example, as the speed increases, the illumination may be directed further away from the vehicle and as the vehicle decelerates the illumination may be directed closer to the vehicle towards the roadway. Base lighting element  104  and variable lighting element  108  may also be at least partially directed towards vehicle  112  to illuminate vehicle  112 . The side and rear mounted base lighting element  104  and variable lighting element  108  provide visibility of objects for others outside the vehicle such as other motorists, pedestrians, cyclists, cameras, or other vehicle detectors and to also improve the visibility and identity of the vehicle itself.  
         [0025]     In mobile VLS  103 , synchronizer  110  synchronizes the lighting system of the vehicle by using any available standard timing device or the wireless synchronization signal emitted from synchronizer  110  of VLS  102 . The standard timing device is static and typically will, have priority over the wireless synchronization signal. Exceptions to the priority may include emergency vehicles or other special events.  
         [0026]     In the case of an emergency vehicle or other special event, the emergency vehicle or some other source will send a priority signal that will override the lighting pattern of VLS  102  and VLS  103 . For example, if a police car or fire engine is speeding to an accident or fire, then all static VLS  102  within a two-block radius may flash a red light. Also, all mobile VLS  103  in the direction of the speeding car or fire engine may flash their lights. This would alert all drivers pedestrians that a police or fire engine is in their area and the drivers and pedestrians could take the appropriate action.  
         [0027]      FIG. 2  depicts a method of using the VLS  102  and VLS  103 . When the VLS  102  or VLS  103  is first activated, Step  200 , the synchronizer  110  checks to determine if there is a master synchronizer  110  to synchronizes the clock in the synchronizer  110 , Step  202 . If there is a master synchronizer  110 , the synchronizer  110  uses the master synchronizer  110  to synchronize its clock, Step  204 . If there is not a master synchronizer  110 , the synchronizer  110  checks to determine if there is a standard timing device to synchronizes the clocks in the synchronizer  110 , Step  206 . If there is a standard timing device, such as the AC sine wave described above, the synchronizer  110  uses the master or standard timing device to synchronize its clock, Step  208 . If there is not a standard timing device, then the synchronizer  110  determines if there is a lower priority synchronization signal such as a wireless synchronization signal from a synchronizer  110  that is not a master synchronizer  110 , Step  210 . If there is a lower priority synchronization signal, the synchronizer  110  uses that synchronization signal to synchronize its clock, Step  212 . Steps  202  through  212  allow all the clocks of any VLS  102  and VLS  103  within a given area to be to be synchronized. If there is not a lower priority synchronization signal, then the synchronizer  110  uses the last clock setting available, such as a factory clock setting or the last synchronized clock setting, Step  214 . After the clock is synchronized, the synchronizer  110  sends out a wireless synchronization signal, Step  216 .  
         [0028]     Next, as shown in  FIG. 3 , the synchronizer  110  checks to determine if there is a master timing signal from a master synchronizer  110  to synchronizes the timing and sequence of the lighting intensity, color, and direction of illumination from base lighting element  104  and variable lighting element  108 , Step  302 . If there is a master timing signal, the synchronizer  110  uses the master timing signal to synchronize the timing and sequence of the lighting intensity, color, and direction of illumination from base lighting element  104  and variable lighting element  108 , Step  304 . If there is not a master timing signal, the synchronizer  110  checks to determine if there is a lower priority timing signal such as a wireless timing signal from a synchronizer  110  that is not a master synchronizer  110 , Step  306 . If there is a lower priority timing signal, synchronizer  110  uses that timing signal to synchronize the timing and sequence of the lighting intensity, color, and direction of illumination from base lighting element  104  and variable lighting element  108 , Step  308 . Steps  302  through  308  allow all the timing and sequence of the lighting intensity, color, and direction of illumination from base lighting element  104  and variable lighting element  108  for each VLS  102  and VLS  103  within a given area to be to be synchronized. If there is not a lower priority timing signal, then the synchronizer  110  uses the preprogrammed timing signal for the timing and sequence of the lighting intensity, color, and direction of illumination from base lighting element  104  and variable lighting element  108 . After the timing sequence is established, the synchronizer  110  sends out a wireless timing signal, Step  312 .  
         [0029]     For example, vehicles driving in the north direction may receive a timing signal to emit blue lights at a frequency of 0.5 seconds northward and vehicles traveling in the south direction may receive a timing signal to emit green light at a frequency of 0.5 seconds southward. The lighting difference provides the increased contrast necessary to see more objects in the roadway.  
         [0030]     A vehicle mounted VLS  103  may be programmed such that if no other vehicle is within a predetermined range, such as approximately 1000 to 1500 feet, then no side and rear vehicle lighting is emitted. The range may be established by the detection of a wireless signal from a VLS  103 .  
         [0031]     The synchronizer  110  can optionally be configured to include a detector component  114  to detect a predetermined signal such as one from an emergency vehicle, motion detector, noise detector, distress signal, traffic signal, or other unrelated occurrence. If the detector is activated, the VLS  110  may noticeably modify the light emission to produce a flash, flash red, or other color, or produce some other noticeable change. The VLS  102  or VLS  103  response to a predetermined signal may vary with the source of signal. For example, the VLS  102  or VLS  103  may produce a red tint appearance when a traffic signal ahead is red, red flash overtones when an emergency vehicle is nearby, or flash yellow overtone when a lane is closed or other trouble is ahead. Also, fixed lighting may be turned off or dimmed when no vehicles are present or are not in close enough proximity to be of sufficient value to warrant the illumination. This could save on the overall cost of operating a fixed lighting system.  
         [0032]     Preferred forms of the invention have been shown in the drawings and described above, but variations in the preferred forms will be apparent to those skilled in the art. For example, the VLS  102  may be used inside a building. The preceding description is for illustration purposes only, and the invention should not be construed as limited to the specific form shown and described. The scope of the invention should be limited only by the language of the following claims.