Road lighting

Abstract

Systems, devices, and methods are disclosed in which one or more light sources, detectors, processors, and controllers are configured such that light from the one or more light sources enhances the ability of a human or automated vehicle driver to identify and avoid pedestrians. The one or more light sources can provide spot illumination to a moving object or pedestrian on a road surface, with the spot illumination following the moving object or pedestrian along a portion of the road surface. The one or more light sources can project an image onto the ground or other surface. The light source can be carried by the pedestrian or on a personal vehicle used by the pedestrian. The light source can be stationary and provide illumination for a crosswalk.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to U.S. Provisional Patent Application No. 62 / 608,963, filed on December 21, 2017, entitled “Roadway Lighting,” European Patent Application No. 18163162.3, filed on March 21, 2018, entitled “Roadway Lighting,” U.S. Patent Application No. 16 / 228,506, filed on December 20, 2018, entitled “Roadway Lighting,” and U.S. Patent Application No. 16 / 228,514, filed on December 20, 2018, entitled “Roadway Lighting,” and U.S. Patent Application No. 16 / 228,516, filed on December 20, 2018, entitled “Roadway Lighting.” Each of these applications is hereby incorporated by reference in its entirety. Technical Field

[0003] The present invention relates generally to lighting, and more particularly to road lighting. Background Art

[0004] Human drivers or automated vehicles approaching an intersection or other roadway junction must identify and avoid pedestrians, cyclists, or other persons in personal transportation vehicles (collectively referred to herein as "pedestrians") who are in or entering the path of the vehicle. Typically, this is accomplished through the use of marked intersections with built-in signal and spotlights. However, even in these situations, under various road and lighting conditions, it can be difficult for drivers to identify pedestrians or cyclists in time to avoid an accident. Furthermore, pedestrians and cyclists often cross the roadway or travel along the side of the roadway where such devices are not available.

[0005] 40 CFR 85.1703 defines a motor vehicle as follows: (a) For purposes of determining the applicability of section 216(2), a self-propelled vehicle capable of transporting one or more persons or any material or any permanent or temporary fixed device shall be considered a motor vehicle unless any one or more of the following criteria are met: in which case the vehicle shall be considered a non-motor vehicle: (1) the vehicle's maximum speed on a level paved surface cannot exceed 25 miles per hour; or (2) the vehicle lacks features normally associated with safe and practical street or highway use, including, but not limited to, reverse gear (except for motorcycles), a differential, or safety features required by state and / or federal law; or (3) the vehicle has features that make its use on streets or highways unsafe, impractical, or extremely unlikely, including, but not limited to, tracked road contact devices, excessive size, or features normally associated with military combat or tactical vehicles, such as armor and / or weaponry. (b) [Reserved] [39 FR 32611, September 10, 1974, as amended by 45 FR 13733, March 3, 1980; 73 FR 59178, October 8, 2008; 75 FR 22977, April 30, 2010].

[0006] This specification follows this definition of a motor vehicle, so non-motorized vehicles will include such transportation devices or means as unicycles, bicycles, tricycles, scooters, roller skates, etc. This specification designates these non-motorized vehicles as personal transportation vehicles, even if they can transport more than one person, such as a bicycle or scooter can accommodate more than one person. These personal transportation vehicles can also be self-propelled, as long as their maximum speed on a level paved road is 25 miles per hour or less. Such personal transportation vehicles include electric scooters, such as Segways, or electric roller skates. Summary of the Invention

[0007] This specification discloses systems, devices, and methods in which one or more light sources, detectors, processors, and controllers are configured such that light from the one or more light sources enhances the ability of a human or automated vehicle driver to identify and avoid pedestrians. The one or more light sources can provide spot illumination to a moving object (e.g., a pedestrian) on a road surface, with the spot illumination following the moving object or pedestrian along a portion of the road surface. The one or more light sources can project an image onto the ground or other surface. The one or more light sources can be carried by the pedestrian or on a personal vehicle used by the pedestrian. The one or more light sources can be stationary and provide illumination for a crosswalk.

[0008] These and other embodiments, features, and advantages of the present invention will become more apparent to those skilled in the art when reference is made to the following more detailed description of the invention taken in conjunction with the accompanying drawings, which are first briefly described. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 Schematically depicts a plan view of an intersection of two roads at which an exemplary embodiment of a road lighting system as described herein is deployed.

[0010] Figure 2 A plan view of pedestrians in a crosswalk using another example embodiment of a roadway lighting system as described herein is schematically shown.

[0011] Figure 3 Another plan view of an intersection of two roads is schematically shown at which an exemplary embodiment of a roadway lighting system as described herein is deployed, with some lighting components shown in side view rather than in plan view.

[0012] Figure 4 Schematically illustrates an arrangement of components used in the example roadway lighting systems described herein.

[0013] Figure 5 Schematically illustrated is another plan view of the intersection of two roads at which an exemplary embodiment of a roadway lighting system as described herein is deployed, with some lighting components shown in side view rather than plan view, and a block diagram showing the processing and control components of the system superimposed.

[0014] Figure 6 is a block diagram of an example embodiment of a roadway lighting system as described herein, illustrating optional interconnection of the system with mobile devices and / or automobiles via a network.

[0015] Figure 7 is a block diagram of an example embodiment of a portable roadway lighting system as described herein, illustrating optional interconnection of the system with a mobile device and / or a car via a network.

[0016] Figure 8A and Figure 8B Shown are a plan view and a schematic diagram, respectively, of an exemplary MxN matrix of pixelated microLEDs that can be used as a light source in a roadway lighting system as described herein.

[0017] Figure 9A A schematic partial cross-sectional view of a portion of an exemplary MxN matrix of pixelated microLEDs that can be used as a light source in a roadway lighting system as described herein is shown. Figure 9B and 9C Schematic plan view showing an exemplary arrangement of n- and p-electrodes in an exemplary microLED.

[0018] Figure 10A and Figure 10B 1 and 2 show schematic partial cross-sectional views of a portion of other exemplary MxN matrix pixelated microLEDs that can be used as a light source in a roadway lighting system as described herein.

[0019] Figure 11 A schematic partial cross-sectional view of a portion of another exemplary MxN matrix of pixelated microLEDs that can be used as a light source in a roadway lighting system as described herein is shown.

[0020] Figure 12 A schematic partial cross-sectional view of a portion of another exemplary MxN matrix pixelated microLED that can be used as a light source in a roadway lighting system as described herein is shown, in combination with a schematic partial cross-sectional view of a portion of a CMOS silicon backplane that can be used to switch pixels in the array on and off. DETAILED DESCRIPTION

[0021] The following detailed description should be read with reference to the accompanying drawings, in which the same reference numerals refer to the same elements in different drawings. The accompanying drawings, which are not necessarily drawn to scale, depict selective embodiments and are not intended to limit the scope of the invention. The detailed description illustrates the principles of the invention by way of example and not limitation.

[0022] The illumination and / or projection device (light source) used in the systems, devices, and methods described herein can be or include an LED array or a laser system. An LED and laser device is discussed in U.S. Patent Application No. 15 / 802,273 by the same assignee, which is incorporated herein by reference in its entirety. A pixelated LED array is described herein, including a microLED array and a laser pump array. Such an LED array will also be referred to below. Figures 8A-12 Further description.

[0023] One of the visual tasks of motor vehicle drivers approaching an intersection is to visualize pedestrians on the road surface through silhouette vision, assuming that the illuminated road surface allows for the perception of people as "shadows" with negative contrast. However, this is an oversimplification of the real situation. In practice, car headlights provide competing positive contrast, which can render people virtually invisible at the transition point (zero contrast). Therefore, additional local illumination is required to ensure positive contrast.

[0024] Additional lighting must alert drivers to the presence of the intersection and make pedestrians as visible as possible in the intersection area. The areas at both ends of the intersection where pedestrians are waiting to enter should be adequately illuminated. When measured in the vertical plane, the lighting should be significantly higher than the horizontal illuminance produced on the roadway by the road lighting. It should also prevent glare from reaching approaching drivers. One solution is to use luminaires with asymmetrical light output, directing light to the side of pedestrians facing traffic a short distance before the intersection in the direction of approaching traffic.

[0025] In addition to marked crosswalks with built-in signal and spotlights, pedestrians are often required to cross roads that do not have such equipment built in. Furthermore, for pedestrians forced to walk on roads without sidewalks and cyclists on roadsides without bike lane markings, proper spotlighting is key to avoiding collisions at night.

[0026] New innovations in automotive lighting, using LED matrices and laser systems for adaptive lighting, could employ a camera capable of detecting poorly lit objects, such as pedestrians and animals, and directing a beam of light toward them before the driver perceives them. However, pedestrian safety will need to be provided to everyone, regardless of the vehicle they drive, until such systems become cost-effective enough to fit most vehicles and until the number of such vehicles on the road becomes dominant.

[0027] The U.S. Department of Transportation Federal Highway Administration publication number FHWA-HRT-08-053, titled "Mid-block Crosswalk Lighting Design Information Report," contains some basic concepts of crosswalk illumination. Illuminance (E) is the amount of light falling on a surface area and can be measured in lux (lx), which is equivalent to lumens per square meter (lm / m 2 ). The illuminance on a plane perpendicular to the direction of light propagation, such as a street surface, is equal to the luminous intensity (I) divided by the square of the distance (D). Distance D is the mounting height of the light source (h) divided by the sine of the angle between a line from the measurement point on the horizontal street surface to the light source and the vertical:

[0028] E = I / D 2 = I / (h / sinɸ) 2 , for a point on the street directly below the light source (ɸ=90°), then E = I / h 2 .

[0029] For a pedestrian crossing the street, the illuminance on the pedestrian is the illuminance E multiplied by the cosine of the angle between the direction of light propagating to the pedestrian and the normal to the plane. This is the vertical illuminance E vert , is the illuminance of a vertical surface (such as a pedestrian). If the height of the pedestrian is h p , then the vertical illuminance of pedestrians is:

[0030] E vert = I cosɸ / D 2 = (I cosɸ) / ((h- h p ) / sinɸ) 2 = I cosɸ sin 2 ɸ / (h- h p ) 2 .

[0031] Luminance (L) is the light emitted, transmitted, or reflected from a surface in a specific direction per unit area and can be expressed in Cd / m 2 Candela is measured in nits. Candela is equivalent to lumen / steradian (lm / sr). In the case of a pedestrian on the street, an observer in a vehicle will perceive the brightness of the (perpendicular) illuminance reflected by the pedestrian. This is related to the brightness of the pedestrian when viewed from a specific direction. However, the appearance of the surrounding environment and the observer's eye's adaptation to the brightness of objects also play a role. In this case, both brightness and contrast are used to calculate the appearance of the object or pedestrian.

[0032] Light reflected by a surface is reflected, absorbed, and / or transmitted. For pedestrians, we are primarily concerned with reflected light. There are various types of reflected light, such as specular and diffuse. Specular reflection, such as from a mirror or mirror-like surface, occurs at the opposite angle of incidence with an intensity nearly equal to that of the incident ray. With diffusely reflecting surfaces, light is scattered and reflected in all directions, which is the case for pedestrians, as clothing is primarily a diffuse reflector. The brightness of a perfect diffuse reflector is:

[0033] L=RE / π,

[0034] Where R is reflectance, E is illuminance, and π is π steradian.

[0035] Contrast is the visual difference between an object, such as a pedestrian, and its background, and is typically expressed as:

[0036] c = (L p –L background ) / L background .

[0037] Contrast can be positive or negative, and can range from very large positive numbers (when the background brightness is very low) to numbers close to -1 (when the object brightness is very low).

[0038] For pedestrians in this situation,

[0039] c = ((R p E vert / π)–L background ) / L background .

[0040] The only variable that can be controlled is the vertical illumination of the intersection light source, lamp or luminaire on the pedestrian. The background brightness is determined by the surrounding environment and can be very low in a rural environment or very bright in an urban street environment with many well-lit retail stores. p The reflectivity of reflective clothing depends largely on the pedestrian's clothing. Choosing white clothing can significantly improve visibility across a wide range of illumination, while the visibility of denim clothing is greatly affected by illumination. Reflective clothing worn at night can greatly improve pedestrian safety.

[0041] Bright road surfaces or bright lighting in shops or stores increase the background brightness, reducing contrast and making pedestrians more difficult to identify. To compensate for the higher background brightness L background , the vertical illuminance E must be increased vert , so that drivers can clearly see pedestrians in the crosswalk. Whether the contrast of pedestrians is positive or negative (contrast polarity) and the uniformity of the pedestrian contrast (contrast variance) are two other important issues in determining the visibility of pedestrians crossing or walking along the road.

[0042] Both contrast polarity and variance vary with the distance the driver is from the pedestrian. At distances greater than 300 feet, the background luminance is generally higher than the pedestrian's. At distances less than 100 feet, the vehicle's low-beam headlights provide sufficient vertical illuminance to make the pedestrian appear brighter than the background, resulting in a positive contrast ratio. Between 300 and 100 feet, the contrast polarity changes from negative to positive, with the pedestrian invisible during this transition. The lighting system must ensure that pedestrians are visible at all distances, providing sufficient time for the driver to react and the vehicle to stop.

[0043] In reality, the contrast of pedestrians is not uniform. The feet and lower legs of a pedestrian may have negative contrast against the bright road surface, while the rest of the pedestrian may have positive contrast against the darker background. Maintaining a given level of negative contrast is difficult for conventional lighting systems, so it is considered good practice for lighting systems to provide sufficient positive contrast to detect pedestrians at a sufficient distance for the vehicle driver to react and stop. Depending on the background brightness, a vertical illuminance E of at least 10, 20, or 30 lx is required. vert To provide adequate pedestrian visibility.

[0044] Glare is another consideration when designing crosswalk lighting systems. Glare can come from headlights of oncoming vehicles between the observer and the crosswalk, or from wet road surfaces reflecting light back at the observer. Glare occurs when the brightness is much higher than the level to which the observer's eyes are adapted. Discomfort glare occurs when the observer experiences discomfort or pain when viewing a light source, but disabling glare can limit or prevent the observer from performing visual tasks, such as detecting pedestrians. Roadway and crosswalk lighting should be installed to mitigate disabling glare. Detectors or sensors in roadway lighting systems can detect these glare conditions based on oncoming traffic and road reflectivity.

[0045] Objects such as pedestrians have a threshold contrast C Threshold , at the threshold contrast C Threshold Under these conditions, the object can be detected with a detection probability of 50%, and depends on factors such as the viewing angle α of the object related to its size, the observation time t observe Length, observer's adaptation brightness L adaption For pedestrian safety, the lighting conditions must provide a contrast ratio greater than the threshold C. Threshold The actual contrast C Actual .

[0046] The visibility level VL is defined as the ratio of the actual contrast to the threshold contrast:

[0047] VL=C Actual / C Threshold =C Actual / C Threshold (α, t observe , L adaption , age)

[0048] The higher the VL, the greater the chance that a pedestrian will be seen. VL provides a measure of the performance of a lighting installation.

[0049] Figure 1 Schematically shows a plan view of an intersection of two roads 102 and 103. The embodiment of the present invention includes a light source 100 and one or more light sources 105. The light source 100 can be located above the crosswalk 104 (and optionally in front of the crosswalk 104) to provide vertical illumination to provide an illumination E horiz The light source 105 may be located near one or both ends of the crosswalk, for example, to provide E vert components, and / or include light sources to provide more E vert and E horiz These light sources can also project images as described below. Light sources 100 and 105 can be or include LED and laser light sources.

[0050] Additionally or alternatively, one or more light sources may be carried by pedestrian 106 in the form of a handheld device, such as Figure 2 The one or more light sources may be, for example, a mobile phone or other pocket-sized device and / or may be wearable on the pedestrian, for example on a belt or clipped to a pocket, or worn on the shoulder, or worn around the neck or on a bicycle, for example on the handlebars, under the seat, on a peddle, on the wheel, or on the spokes.

[0051] Light sources (portable or fixed) can provide E on pedestrians vert The image 107 may be projected onto a pedestrian crossing or at a vertical location noticeable to a driver (but not, for example, in a location that would dazzle or blind a vehicle driver), such as where a crosswalk, stop, yield, or warning sign might be conventionally placed. Such display images and text may be projected on both sides of a roadway where there is traffic coming from both directions. For example, an image 107 displaying the text "Stop" may have an octagonal shape on the roadway.

[0052] This lighting and projection equipment can be used at traditional crosswalks where additional lighting and warnings are required, as well as at marked crosswalks where pedestrians are not allowed to cross but must cross. Marked crosswalks can incorporate this technology into installed equipment that also provides E vert and E horiz Lighting can project an image of a crosswalk and a circle or other shape around the pedestrian that follows the pedestrian(s) across the street. The projection can also include arrows indicating the direction the pedestrian is moving. Spotlights can be used in place of or in conjunction with this lighting, which can also follow the pedestrian across the street.

[0053] These projections may include images and text on the sidewalk or above a location readily visible to the driver of the vehicle in all relevant directions of travel, without dazzle, glare or blinding, and may be multi-colored, such as white, red, yellow, green and blue ( Figure 2 and Figure 3 This mounted and mobile lighting system can be used not only to cross streets, but also by pedestrians and cyclists walking or riding along the edge of the street. These devices can also be used on pedestrian or sidewalks with little or no lighting.

[0054] For example, Figure 4As shown, these illumination systems may employ one or more detectors, sensors, or cameras that may operate in the IR, ultrasonic, radar, and / or LiDAR ranges. The controller and processor may use the detector, sensor, and / or camera output signals as input to output illumination control to the light source(s) and control the illumination of pixel elements in the matrix array by controlling which CMOS transistors are turned on and off, or by controlling the rastering of laser beams to color conversion elements or pixels, for example, through a MEMS-based mirror array or an acousto-optic reflector or deflector. The road lighting system may be manually activated by a pedestrian, for example by pressing a Figure 4 A button (not shown) on the center light source support rod. Alternatively, the road lighting system can be activated by a pedestrian sending a signal from a mobile device, or it can be activated automatically when the presence of a pedestrian is detected.

[0055] Alternatively or additionally, vehicle-to-vehicle, infrastructure, pedestrian, target, or object (V2X) communications can also be used to provide location, speed, vehicle type, and size, etc. to the adaptive front, rear, and side exterior lighting systems. Global Positioning System communications can also be used. An imaging processor can take input from cameras, IR sensors, LiDAR, radar, ultrasonic receivers, etc. to create an image of the traffic and pedestrian situation, including location, speed, direction, etc., and send signals to a controller, which can optionally be integrated with the processor, to control one or more lighting fixtures, light projection of warning images, such as traffic-type signs that can be multi-colored and include text, crosswalk projection and pedestrian highlighting, and communications with vehicles and pedestrians.

[0056] For example, a spotlight can illuminate pedestrians and provide sufficient illumination E in the vertical plane. vert Multiple point illumination (horizontal light on pedestrians) can be used for each pedestrian in the intersection, which can be emitted from a single light source (e.g., an array), or multiple light sources separated by space can be used. The point illumination does not have to be circular, and can be any shape that illuminates the pedestrian(s) and can follow the pedestrian(s) in real time. This point illumination can be provided by propagating light in a direction horizontal to the sidewalk and perpendicular to the vertical plane of the pedestrian, and increases the vertical illuminance E vert .

[0057] The sidewalk area around the pedestrian can be provided with some additional spot illumination, enough to attract the attention of the vehicle driver, but not enough to significantly reduce the pedestrian contrast. The horizontal illumination can also follow the pedestrian(s) in real time and can be of any shape, including, for example, a rectangular portion of an intersection that follows the movement of the pedestrian(s). This E horizThe illumination may be in the form of a projection, where the area around the pedestrian may be highlighted with a projection on or above the sidewalk, such as a partial or full circle-oval or square-rectangle shape, using, for example, white and red, and a green arrow may be projected to indicate the direction of movement.

[0058] Horizontal illuminance that is not part of the projection can be suppressed in the area around pedestrians and projections to maximize contrast, horizontal illuminance E horiz This suppressed or dark spot can also follow pedestrians.

[0059] A projection of a traffic sign image, which may include text and color, may be projected onto the ground ( Figure 2 and Figure 3 ) or above or on a pre-positioned mounted screen, which may be diffusely reflective or translucent to transmit the projection image in a diffuse manner to the opposite side of the receiving projection image for viewing by oncoming vehicles.

[0060] As an alternative or supplement to fixed signs, displays can be used that can be programmed to change color and display a warning when a pedestrian enters the street. This can be accomplished using one of the existing detectors and switched by the lighting controller, or a separate unit can be used. The detector can also determine road conditions, such as reflectivity from rain and snow, and adjust the projection accordingly for better visibility and positioning, thereby increasing stopping distances. Additionally or alternatively, weather information can be received from the internet or Ethernet communications. The processor and / or controller can be connected to the network or Ethernet, which can transmit visual and / or audible warnings to oncoming vehicles. This can be a visual warning on the dashboard display, a head-up display (HUD), or simply a warning light. An audible warning can also come from the dashboard display or HUD, or it can activate the radio speakers. Alternatively, a mobile phone or navigation device in the vehicle can be used to issue an audible and / or displayed warning. Similarly, warnings can be communicated to pedestrians via a mobile phone or other handheld lighting and / or communication device. The pedestrian's communication device can also communicate with the crosswalk's lighting system to activate the illuminated intersection and receive instructions from the system regarding, for example, when to enter the crosswalk.

[0061] An emitting source such as an infrared (IR) light source, for example a VCSEL or LED array, can be used with a detector such as a camera to detect pedestrians. The camera and light source can be mounted on or integrated into one or more visible light sources 100 or 105, for example, as Figure 4 as shown, or can be installed separately.

[0062] like Figure 5As generally shown in FIG, the signals from the camera (detector) can be processed by a processor or image analyzer and used by the lighting controller to control the light sources 100 and 105 to perform the operations described above. In this figure, the line schematically linking the processor or image analyzer to the light source 105 represents communication with the camera (detector) co-located with the light source 105. Similarly, one of the lines schematically linking the lighting controller to the light source 105 indicates communication with an emission source used in conjunction with the camera (detector) co-located with the light source 105.

[0063] Optionally, the camera can also detect the higher intensity white headlight beams of oncoming vehicles and the lower intensity red taillights of passing vehicles. Figure 6 As shown, a camera can include a CCD and a digital signal processor (DSP) communicating with each other. The DSP can also communicate with a processor or image analysis unit, which can have an image input connected to the digital signal processor, an imaging processing unit, a CPU that can send an exposure signal back to the camera DSP, programs, and memory. The camera DSP can also include an analog-to-digital converter (ADC) that receives the CCD input, a color converter unit that outputs a digital image signal to the image input of the imaging processing unit, an exposure control unit that outputs a signal to the CCD, and a register that receives the exposure signal from the CPI of the image processing unit and outputs a signal to the exposure control unit and the color converter unit. The image analysis unit or the processor's CPU can output a signal to the controller of the light source.

[0064] Based on the processor output, the controller can turn the various light sources on and off and control the beam pattern from each of the various light sources. Optionally, the image analysis unit or the CPU of the processor can also output signals to the control unit of the IR light source, or the controller can operate and control all light sources including visible light and IR.

[0065] This illustrates one embodiment, and instead of or in addition to the camera and IR source, ultrasound, LiDAR, radar, thermal sensors that can detect IR, or pressure sensitive mats that can be mounted underground with appropriate sensors or detectors, and optional supplemental sources for generating radiation or signals of the source to be detected may be used.

[0066] As mentioned above Figure 2 As described above, instead of or in addition to pre-positioned and fixedly mounted crosswalk lighting systems, portable systems can be used. The lighting system can be carried or worn by pedestrians or cyclists or mounted on bicycles or other personal transportation such as skateboards, roller skates or scooters. Figure 7 As schematically shown, the portable device 120 may include a projector and / or illuminator, a detector, a computing module, and a transceiver.

[0067] The projector / illuminator can be laser or LED based and use reflectors, lenses, and mirrors. The detector can include one or more sensors to detect motion and / or distance and can be, for example, a gyroscope, accelerometer, GPS receiver, camera, or microphone. The transceiver can be connected to a network or Ethernet network and receive and send information to, for example, a remote server, mobile device, or vehicle. Weather, traffic, and / or road conditions can be transmitted from the remote server to the portable device.

[0068] A mobile device such as a mobile phone, PDA, or other similar device can transmit information about vehicles and other pedestrians to the portable device, and vice versa. Information can also be transmitted directly from the vehicle to the pedestrian's or cyclist's portable device, and information about the pedestrian / cyclist can be transmitted back. The computing module can obtain the detector and transceiver inputs to generate appropriate illumination and / or projected display images, text messages, and colors based on these inputs. The computer module can also send appropriate warnings to the mobile device, vehicle, and remote server via the transceiver over a network or Ethernet. The system is particularly useful when pedestrians are walking or riding on unmarked medians and intersections, and when pedestrians or cyclists are walking or riding on dimly lit or busy streets to cross street intersections.

[0069] The controller and processor can be integrated into the same unit or module. Similarly, visible light and IR light sources can be integrated into the same lighting fixture, as can any optional supplemental radiation source, such as ultrasound, radar, VCSEL, LED array, or LiDAR. It is also possible to integrate all the electronic components of the light source together, so that the detector radiation, detector, processor, controller, and visible light emitting element are all in a module or lighting fixture. This module or lighting fixture can be called a smart lamp or smart lighting source.

[0070] As described above, one or more light sources used in the systems described herein can provide horizontal and vertical illumination. In various embodiments, the vertical illumination can be less than the horizontal illumination, the vertical illumination can be equal to the horizontal illumination, and the vertical illumination can be greater than the horizontal illumination.

[0071] Generally, it is desirable that the vertical illuminance be greater than the horizontal illuminance so that the pedestrian is in positive contrast and background brightness is minimized, but the crosswalk is typically illuminated so its presence is visible. However, some variations of the systems described herein have optional projections that can work in conjunction with the spot lighting to provide a line or boundary that partially or completely surrounds the pedestrian, and / or the projection can be an image of a traffic sign or text message. These projections can be projected onto the ground or sidewalk and can have a local horizontal illuminance that is much higher than the surrounding horizontal illuminance. In these embodiments with projections, the projected horizontal illuminance can be higher than the surrounding local horizontal illuminance and close to the pedestrian's vertical illuminance, equal to the pedestrian's vertical illuminance, or greater than the pedestrian's vertical illuminance.

[0072] Preferably, the spatial area of the projection does not significantly overlap with the spatial area of vertical illumination of the pedestrian as seen by the driver of an oncoming vehicle, resulting in reduced contrast for the pedestrian or the projected image. In one embodiment, the vertical illumination is half or more of the horizontal illumination. In another embodiment, the vertical illumination is at least equal to the horizontal illumination. In yet another embodiment, the vertical illumination is at least twice the horizontal illumination. In another embodiment, the vertical illumination is at least five times the horizontal illumination.

[0073] In another embodiment, the projected horizontal illuminance is at least twice the horizontal illuminance of the surrounding environment. In another embodiment, the projected horizontal illuminance is at least five times the horizontal illuminance of the surrounding environment. In another embodiment, the projected horizontal illuminance may be approximately equal to the vertical illuminance of the pedestrian. In another embodiment, the projected horizontal illuminance may be greater than the vertical illuminance of the pedestrian. In another embodiment, the vertical illuminance of the pedestrian has minimal overlap with the projected horizontal illuminance in the field of view of the driver of an oncoming vehicle.

[0074] In one embodiment, the brightness of a pedestrian is at least twice the brightness of the background or partial background (outside the projection). In another embodiment, the brightness of a pedestrian is at least five times the brightness of the background. In yet another embodiment, the brightness of a pedestrian is at least ten times the brightness of the background.

[0075] In one embodiment, the vertical illuminance for pedestrians is at least 10 lx. In another embodiment, the vertical illuminance for pedestrians is at least 20 lx. In yet another embodiment, the vertical illuminance for pedestrians is at least 30 lx. In yet another embodiment, the vertical illuminance for pedestrians is at least 50 lx. In yet another embodiment, the vertical illuminance for pedestrians is at least 100 lx.

[0076] The system described herein can provide point illumination or illumination of a pedestrian, wherein the vertical illumination of an object or pedestrian can be greater than the vertical illumination outside the spatial area illuminated by the point illumination. In one embodiment, the point vertical illumination is at least 1.5 times the vertical illumination outside the point. In another embodiment, the point vertical illumination is at least twice the vertical illumination outside the point. In yet another embodiment, the point vertical illumination is at least five times the vertical illumination outside the point. The horizontal illumination around the pedestrian can also be dimmed or turned off, and the dark hole follows the pedestrian, so that the vehicle driver can view the vertical illumination of the point illumination and the optional projected horizontal illumination with increased contrast.

[0077] The roadway lighting system described herein can consume less power than conventional systems. For example, point lighting for individual pedestrians in an intersection can provide excellent vertical illumination for pedestrians along the entire length of the intersection, rather than having to provide this level and uniform vertical illumination along the entire length of the intersection as the point follows the pedestrian(s).

[0078] In contrast, for traditional lighting systems, power consumption does depend on the illuminated area. For a typical 4-meter-wide crosswalk, a traditional lighting system luminaire is installed in the center of the crosswalk, 4 meters in front of oncoming traffic, 0.5 meters from the curb, and at a height of 5 meters: for a 3.5-meter-long one-way street, using a 13,500-lumen metal halide lamp, it can consume 150 watts and have a vertical illuminance average of 85 lx with a poor uniformity of 0.6, and using two 19,000-lm bulbs can consume 500 W for a 7-meter-long two-lane street, it can have a vertical illuminance average of 180 lx with a uniformity of 0.7.

[0079] The fixed lighting system described herein can be turned off when no pedestrians are detected, or can be dimly illuminated with horizontal illumination to make drivers aware of the intersection even if pedestrians are not present. When a pedestrian is detected, the horizontal illumination can be increased so that the crosswalk is adequately illuminated, and increased vertical illumination is provided to make the pedestrian easily visible. The crosswalk lighting system of the present invention can use less than 300 watts for a two-lane intersection and less than 90 watts for a single-lane intersection. In addition, such a system can use less than 200 watts for a two-lane intersection and less than 60 watts for a single-lane intersection. With the portable lighting system of the present invention, power consumption can be less and less dependent on the length of the intersection because the vertical illumination is provided at a nearly fixed distance from the portable device to the bracket, and if projections are also used, they can have a fixed length, such as a long projection of 4 to 10 feet for the crosswalk.

[0080] Older designs of crosswalk lighting placed the luminaires directly on the crosswalk. This provided high crosswalk illuminance Ehoriz , but may not be enough to illuminate pedestrians. Newer designs move the light source at least 2 meters relative to the direction of oncoming traffic at the crosswalk to provide the necessary vertical illuminance (E vert ). For computer modeling, a pedestrian can be represented as a 5 foot 10 inch tall, 1 foot diameter cylinder with an 18% reflectivity. Retrofitting or retrofitting older designs that typically use high pressure sodium or metal halide lamps with the LED arrays and / or laser light sources described herein can greatly improve pedestrian visibility without requiring repositioning of infrastructure. Using these lighting systems using LED arrays and / or laser light sources, detectors, optional emitters for the detectors, processors, and controllers can provide greatly improved pedestrian lighting and safety, and can save power. Whether the device is a new installation designed specifically to incorporate this technology, a retrofit device to a new or old conventional design, or a portable system, the potential for improvements in safety and energy consumption exists.

[0081] As mentioned above, the illumination and / or projection device used in the systems, devices and methods described herein may be or include an LED array or a laser. Figures 8A-12 Some aspects of such an LED array are further described.

[0082] Figure 8A and 8B A plan view and schematic diagram of an example MxN matrix of pixelated microLEDs 200 including MxN pixels 205 are shown. The number of individual pixels in the array can be, for example, 2 to 10, which can be used for mobile phone flashlights, etc., 10 to 50 in some embodiments, 50 to 100 in some embodiments, 100 to 500 in other embodiments, 500 to 1000 in other embodiments, 1000 to 2500 in other embodiments, 2500 to 5000 in other embodiments, and 5000 to 10,000 in other embodiments, which can be used for, for example, adaptive vehicle headlights, adaptive streetlights, adaptive crosswalk illumination, etc. Other embodiments include 10,000 to 100,000 and 100,000 to 500,000, which can use LED or laser light sources, 500,000 to 1,000,000 and 1,000,000 to 10,000,000, which can use laser light sources, or can use light sources such as raster-scanned laser(s). Raster scanning can be accomplished with micro-electromechanical systems (MEMS) based mirrors or acousto-optic reflectors or deflectors. These embodiments may be applicable to displays.

[0083] Figure 9AA partial cross-sectional view of one embodiment of an LED matrix array 200 is shown. N-type (205) and p-type (210) semiconductor layers sandwich an active region that emits light. The n- and p-type semiconductor layers and the active region themselves can comprise multiple layers of varying doping levels and compositions. For example, the active region can be a single light-emitting layer, a homojunction, a single heterojunction, a double heterojunction or heterostructure, a single quantum well heterostructure (SQW), a multiple quantum well (MQW) structure, or a superlattice (SL) structure. The n-type and p-type semiconductor layers can be, for example, GaN or AlGaN, and the active region can be InGaN and GaN. Other semiconductor material systems include, for example, AlGaInP, AlGaAs, and AlGaInAsP. Once the epitaxial layers are grown, trenches can be etched through the p-layers and into the thicker n-layers.

[0084] The pn junction can be passivated with a dielectric such as SiO x 、AlO x 、SiON、SiAlON、TaO x 、AlO x Or Si3N4, etc., to prevent short circuits, or can be isolated by ion implantation, such as hydrogen, carbon and oxygen ions. Figure 9A In the example of FIG, such a dielectric can be deposited on the surface of the n- and p-layers in region 220. The metal contacting the n-layer and the dielectric can extend to the p-layer side. The p-metal can be deposited before or after the trench is etched.

[0085] In one embodiment, the metal contact 240 of the n-type material can be extended to the p-side surface, isolated from the p-type material. The p-type and n-type metal electrodes can then be on the same side and bonded to a silicon wafer, which can contain electronic devices such as switching transistors, TVS, open and / or short detection, etc. Bonding can include soldering, such as AuSn or SnAgCu (SAC) solder, or GGI bonding using heat and ultrasonic energy to form an Au bond interconnect.

[0086] After removal of the growth substrate (e.g. sapphire), the metal can be extended beyond the n-layer, for example by plating. If the p-side trench and metallization extend completely through the n-layer to the substrate, the n-metal can be used as a seed for the plating and can be exposed by growth substrate removal, by thinning the n-layer, or by subsequent trench etching from the n-side after substrate removal. The p- and n-metal contacts are preferably reflective and can be, for example, Ag, Al, Ni, Ti, TiW, TiWN, Au, Zn, and combinations and layers thereof. Extensions beyond the n-surface can be reflective metals or TCOs as described above, such as ITO, ISO, AZO, IZO, or dielectrics, such as sapphire, photoresist, SiO x 、SiON、SiAlON、TaO x、AlO x or Si3N4, which can be reflected by TIR or metal coating.

[0087] The extension can be used to hold or contain a wavelength converter 225, such as a phosphor in silicone or other suitable binder or ceramic phosphor. The phosphor can be applied by dispensing, inkjet printing, deposition, EPD, stencil printing, spraying, or molding. The pixels can be, for example, square, circular, oval, or rectangular. Figure 9B and Figure 9C The p-electrode 230 is shown to be square, rectangular, circular, or oval, surrounded by a thin dielectric 235 and an n-electrode 240 around the perimeter. The n-electrode can completely surround ( Figure 9A and Figure 11 ), partially surrounded by ( Figure 10A ), or on one side of the p-electrode ( Figure 12 The n-electrode can also overlap with the p-electrode separated by a dielectric ( Figure 10B ).

[0088] The electrodes may be in the device or through a silicon backplane 245 (e.g. Figure 12 For convenience, the positions of the n-layer and p-layer and the electrodes are shown in the figure, but their positions can also be interchanged, which is opposite to what is shown in the figure.

[0089] Multiple matrix arrays can be used in an illumination device, and these multiple arrays can be spaced apart from each other and need not be adjacent in an extended matrix configuration. For example, one matrix in a crosswalk illumination system can provide crosswalk illumination while another matrix is used to provide spot lighting that follows pedestrians as they cross the street.

[0090] In various embodiments, the pixel size d1 ( Figure 9A and Figure 11 ) can be, for example, from submicron to 1 micron, 1 micron to 10 microns, 10 microns to 50 microns, and 50 microns to 500 microns. The pixel pitch d2 can be determined by the width of the metal layer ( Figure 11 ), or can include actual gaps ( Figure 9A ). The pixel pitch d2 can be, for example, less than 0.1 micron, 0.1 to 1 micron, 1 micron to 5 microns, and 5 to 50 microns. The pixel pitch d2 may depend on the pixel major dimension d1.

[0091] The pixels can be of any shape or combination of shapes, such as circular, square, rectangular, triangular, hexagonal, and combinations thereof. The phosphor particle size can depend on the pixel size d1 and can be at least d1 / 10 or smaller. In some embodiments, the luminous flux of these arrays can be 10 -4to 10 -3 Lumen (lm), 10 -3 to 0.1 lm, 0.1 to 10 lm, 10 to 1000 lm, 1000 to 10000 lm, 10000 to 100000 lm and 0.1 to 5×10 6 In some embodiments, the brightness of these arrays can be 10 to 100 lux (lx), 100 to 500 lx, 500 to 1000 lx, 1000 to 50000 lx, 50000 to 500000 lx, 0.5 X10 6 Up to 1X10 6 lx、1X10 6 Up to 10X10 6 lx and 10X10 6 Up to 5000X10 6 In some embodiments, the illumination of these arrays can be 10 to 100 nits, 100 to 1000 nits, 1000 to 10,000 nits, 10,000 to 100,000 nits, 0.1×10 6 to 1×10 6 nits, 1×10 6 Up to 1000×10 6 nits. The brightness and illuminance of these arrays can be measured without external optics and can include lasers as well as LED arrays. In some embodiments, the luminous efficacy can be 1 to 20 lumens / watt, 20 to 200 lumens / watt, and 200 to 500 lumens / watt. These arrays can be packaged with primary optics, such as lenslet arrays or compound parabolic concentrators (CPCs), and can include secondary optics, such as projection lenses.

[0092] This disclosure is intended to be illustrative and not restrictive. Further modifications will be apparent to those skilled in the art in light of this disclosure and are intended to fall within the scope of the appended claims.

[0093] The following enumerated paragraphs (clauses) provide additional non-limiting examples of the present disclosure.

[0094] 1. A lighting system comprising: a light source; a detector; a processor; and a controller; wherein the system is configured so that light from the light source illuminates a portion of a road surface and provides point illumination to a moving object on the road surface, so that the point illumination follows the moving object along the portion of the road surface.

[0095] 2. The lighting system according to clause 1, wherein the lighting system is fixed and provides lighting for a pedestrian crossing.

[0096] 3. The lighting system of clause 1, wherein the lighting system is portable and provides lighting for one of a pedestrian and a pedestrian using a personal vehicle.

[0097] 4. The lighting system of clause 3, wherein the personal transportation vehicle is one of a bicycle, a scooter, a Segway, and skates.

[0098] 5. The lighting system of clause 1, wherein the light source comprises one of an LED and a laser.

[0099] 6. The lighting system of clause 1, wherein the light source comprises an LED array.

[0100] 7. The lighting system of clause 1, wherein the light source comprises a microLED array.

[0101] 8. The illumination system of clause 1, wherein the light source comprises a laser and a wavelength converter.

[0102] 9. The lighting system of clause 1, wherein the system is further configured to provide a point of reduced horizontal illumination following the moving object along the portion of the road surface to increase contrast.

[0103] 10. The lighting system of clause 1, wherein the system further comprises a projection that at least partially surrounds and follows a pedestrian.

[0104] 11. The lighting system of clause 10, wherein the projection is one of a circle, an ellipse, a square, and a rectangle.

[0105] 12. The lighting system of clause 11, wherein the projection further comprises an arrow indicating the direction of the pedestrian.

[0106] 13. The lighting system of clause 1, wherein the system further comprises a projection of one of a traffic sign and a text message visible to a vehicle driver.

[0107] 14. The lighting system of clause 1, wherein the system further provides a projection comprising one or more colors.

[0108] 15. The lighting system of clause 7, wherein the microLED array comprises LED chips mounted and electrically connected to CMOS circuitry on a silicon wafer, wherein the LED chips are separated by a dielectric and a metal that extends above the semiconductor surface of the LED chips and is filled with a wavelength converter.

[0109] 16. The lighting system of clause 1, wherein the system comprises a vertical illuminance that is at least twice the horizontal illuminance.

[0110] 17. The lighting system of clause 1, wherein the system comprises a vertical illuminance that is at least five times the horizontal illuminance.

[0111] 18. The lighting system of clause 10, wherein the projected horizontal illuminance is at least twice the horizontal illuminance of the surrounding crosswalk.

[0112] 19. The lighting system of clause 10, wherein the projected horizontal illuminance is at least equal to the vertical illuminance of the pedestrian.

[0113] 20. The lighting system of clause 10, wherein the projected horizontal illuminance is less than the vertical illuminance for the pedestrian.

[0114] 21. The lighting system of clause 1, wherein the system further comprises a transceiver capable of communicating with a network.

[0115] 22. The lighting system of clause 21, wherein the system further comprises a transceiver capable of communicating with at least one of a vehicle, a mobile phone, and a remote server over a network.

[0116] 23. The lighting system of clause 1, wherein the lighting system comprises a non-motor vehicle lighting system.

[0117] 24. A portable illumination device comprising: a light source; a detector; a computer; and a transceiver; wherein the light illuminates a bracket and projects an image on the ground.

[0118] 25. The portable illumination device of clause 24, wherein the light source comprises one of an LED and a laser.

[0119] 26. The portable illumination device of clause 24, wherein the detector is one of an accelerometer, a gyroscope, and a GPS.

[0120] 27. The portable illumination device of clause 24, wherein the transceiver is capable of communicating with at least one of a vehicle, a mobile phone, and a remote server over a network.

[0121] 28. The portable illumination device of clause 24, wherein the image at least partially surrounds and follows the support.

[0122] 29. The portable irradiation device of clause 24, wherein the image further comprises an arrow indicating the orientation of the support.

[0123] 30. The portable illumination device of clause 24, wherein the image comprises one of a traffic sign and a text message visible to a driver of a vehicle.

[0124] 31. The portable illumination device of clause 24, wherein the image comprises one or more colors.

[0125] 32. The portable illumination device of clause 24, wherein the holder is one of a pedestrian and a person in personal transportation.

[0126] 33. The portable irradiation device of clause 32, wherein the personal vehicle is one of a bicycle, a scooter, a Segway, and roller skates.

[0127] 34. The portable illumination device of clause 24, wherein the support is one of a bicycle, a scooter, a Segway, and roller skates.

[0128] 35. The portable irradiation device of clause 24, wherein the support comprises a non-motorized vehicle.

Claims

1. A system for road lighting, comprising: A controller is configured to receive a signal from the processor and, in response, control one or more light sources to illuminate a portion of a roadway and provide spot illumination to the pedestrian as the pedestrian moves on or near the roadway, the spot illumination tracking the pedestrian, the spot illumination of the pedestrian comprising projecting a horizontally brightened area around the pedestrian, wherein horizontal illumination that is not part of the projection comprises a dark spot having reduced horizontal illumination in a plane parallel to the roadway, the dark spot providing increased visual contrast and surrounding and tracking the pedestrian.

2. The system of claim 1, further comprising a processor configured to receive and process signals from the one or more detectors.

3. The system of claim 2, wherein The processor is configured to receive and process signals from the one or more detectors indicating that a motor vehicle on a road is approaching the pedestrian; and The controller is configured to control illumination of the pedestrian such that a vertical illumination component on the pedestrian is visible from the motor vehicle.

4. The system of claim 2, wherein the controller is configured to receive a signal from the processor and, in response, control pixels in an LED array in the one or more light sources to provide the point illumination.

5. The system of claim 2 , wherein the controller is configured to receive signals from the processor and, in response, control pixels in the LED array to provide the point illumination, the projection tracking and at least partially surrounding the pedestrian as the pedestrian moves on or near the roadway. The system of claim 5 , wherein the projection includes an arrow indicating a direction in which the pedestrian is moving.

7. The system of claim 5, wherein the projection comprises a traffic sign, a text message, or both a traffic sign and a text message visible to a driver of a vehicle approaching the pedestrian.

8. The system of claim 5, wherein: A horizontal illuminance component of the projection in a plane parallel to the road is at least twice a horizontal illuminance component of a surrounding road.

9. A system for road lighting, comprising: A controller is configured to receive a signal from the processor and, in response, control one or more light sources to provide point illumination to a pedestrian as the pedestrian moves on or near a roadway, the point illumination tracking the pedestrian, the point illumination for the pedestrian having a vertical illuminance component in a plane perpendicular to the roadway that tracks the pedestrian and a horizontal illuminance component in a plane parallel to the roadway that tracks the pedestrian, the horizontal illuminance component having a different intensity than the vertical illuminance component, wherein the point illumination for the pedestrian includes projecting a horizontal illuminance highlight on an area surrounding the pedestrian, wherein the horizontal illumination that is not part of the projection includes a dark spot having a reduced horizontal illuminance in a plane parallel to the roadway, the dark spot providing increased visual contrast and surrounding and tracking the pedestrian.

10. The system of claim 9, further comprising a processor configured to receive and process signals from the one or more detectors.

11. The system of claim 10, wherein: The processor is configured to receive and process a signal from the one or more detectors indicating that a motor vehicle on a road is approaching the pedestrian; as well as The controller is configured to control illumination of the pedestrian such that a vertical illumination component on the pedestrian is visible from the motor vehicle.

12. The system of claim 10, wherein the controller is configured to receive signals from the processor and, in response, control pixels in the LED array to provide the point illumination, the projection tracking and at least partially surrounding the pedestrian as the pedestrian moves on or near the roadway.

13. The system of claim 12, wherein the projection includes an arrow indicating a direction in which the pedestrian is moving.

14. The system of claim 12, wherein the projection comprises a traffic sign, a text message, or both a traffic sign and a text message visible to a driver of a vehicle approaching the pedestrian.

15. A system for road lighting, comprising: a controller configured to receive signals from the processor and, in response, control one or more light sources to provide illumination, the illumination comprising a projection that tracks and at least partially surrounds the pedestrian as the pedestrian moves on or near the road to horizontally illuminate an area surrounding the pedestrian, the projection comprising an image that tracks and at least partially surrounds the pedestrian as the pedestrian moves on or near the road and includes information related to the pedestrian, wherein horizontal illumination that is not part of the projection comprises a dark spot having reduced horizontal illumination in a plane parallel to the road, the dark spot providing increased visual contrast and surrounding and tracking the pedestrian.

16. The system of claim 15, further comprising a processor configured to receive and process signals from the one or more detectors.

17. The system of claim 15, wherein the projection includes an arrow indicating a direction in which the pedestrian is moving.

18. The system of claim 15, wherein the projection comprises a traffic sign, a text message, or both a traffic sign and a text message visible to a driver of a vehicle approaching the pedestrian.

19. The system of claim 15, wherein: A horizontal illuminance component of the projection in a plane parallel to the road is at least twice a horizontal illuminance component of a surrounding road.

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