LED lamp for road low-position lighting and low-position road lighting system

Abstract

The invention provides an LED (light-emitting diode) lamp (101) for low-position road illumination, which fundamentally solves the problem of dazzling. Comprising LED light sources (2) on a substrate (1), a spreadlight lens (3), a transparent lampshade (12) and a metal radiator (10), the LED light sources (2) are covered with the spreadlight lens (3), the transparent lampshade (12) and the metal radiator (10) one by one, the centers of the LED light sources are arranged in a line, the substrate (1) is arranged in a cavity, and the lower edge of one side, in the polarization direction, of the outer side of the cavity is a cavity straight edge parallel to the light source center arrangement line. The included angle between a plane formed by a straight line arranged at the center of the LED light source and the straight edge of the cavity and the substrate plane (1 ') is smaller than the included angle between the maximum light intensity direction (4) and the substrate plane (1'), the opening of the cavity faces downwards during installation and use, and the lowest point of the straight edge of the cavity is not higher than the lowest point of the lens (3). Therefore, light rays refracted by the lens (3) cannot be directly emitted from the inside of the LED lamp (101) to one side of a road in a horizontal upward direction.

Description

Technical Field

[0001] The invention belongs to the field of LED lamps, in particular to the field of LED lamps used for low-position road lighting. Background Art

[0002] Patent CN102109132A published on June 29, 2011, discloses an LED lamp for low-position lighting, including an array-arranged LED light source unit installed on the same LED substrate. The LED light source unit is composed of a light source and a lens covered on the light source. Bidirectional polarization is achieved through the lens, so that the light from the light source converges in the direction of the vehicle and the ground, which reduces the glare of the low-position light source to a certain extent. However, the LED light source is not a point light source, so the lens itself becomes a strong light source. When the driver looks directly at the lens while driving, there is still glare, and the glare problem has not been fundamentally solved.

[0003] Patent CN110118327A published on August 13, 2019, discloses a method for installing a concealed guardrail lamp and a concealed guardrail lamp. The installation method is that the guardrail lamp is installed on the rear side of the guardrail tube, and the light-emitting surface of the guardrail lamp is located below the guardrail lamp, so that the driver cannot see the lens of the guardrail lamp; the concealed guardrail lamp includes an aluminum profile lamp housing installed on the rear side of the guardrail tube, a light source is arranged in the aluminum profile lamp housing, the bottom of the aluminum profile lamp housing is open, and a light-transmitting cover is arranged at the bottom opening of the aluminum profile lamp housing. The guardrail lamp is installed on the rear side of the guardrail tube and the lens direction of the guardrail lamp is located below the guardrail lamp, so that the driver can avoid looking directly at the lens (i.e., the strong light spot) when driving at a viewpoint above 1.2 meters high and within a range of 10 meters away from the guardrail lamp (one to three lanes), effectively controlling glare and distributing light to the road surface below the horizontal line. The angle between the light-emitting surface of the guardrail lamp and the ground cannot be adjusted, and it is not adaptable to roads of different widths. For wide roads, to achieve the requirement of uniform lighting, excessively high requirements are placed on the refractive ability of the lens, which makes the technology difficult to implement and the price high.

[0004] Article 9.2.2 of the "Road Guardrail Lighting Design Standard" (effective from September 1, 2022) stipulates that the upward luminous flux ratio of lamps should not be greater than 3%. This standard allows the upward luminous flux ratio of lamps to be no greater than 3%. This is a stopgap measure when there was no reliable technical solution to further reduce the upward luminous flux ratio while ensuring the road lighting effect when the standard was formulated. This 3% upward luminous flux will also cause glare, but it only controls the degree of glare below a certain indicator, and it also does not fundamentally solve the glare problem. Summary of the invention

[0005] The present invention provides an LED lamp 101 for low-position road lighting, so that the driver cannot see the lens 3 of the lamp 101, strictly preventing glare. At the same time, a common polarized lens 3 publicly available on the market is selected to adapt to application scenarios of different widths of road surface, thereby achieving low cost. The LED light source comprises an LED light source 2 on a substrate 1, a polarizing lens 3 covering the LED light source 2 one by one, a transparent lampshade 12, and a metal heat sink 10. The centers of the LED light sources are arranged in a straight line, the substrate 1 is placed in a cavity, and the lower edge of the outer side of the cavity on the side of the polarization direction is a straight edge of the cavity parallel to the straight line of the center arrangement of the light source. The angle between the plane formed by the straight line of the center arrangement of the LED light source and the straight edge of the cavity and the substrate plane 1' is smaller than the angle between the maximum light intensity direction 4 (when there is no obstruction; unless otherwise specified below, the maximum light intensity direction refers to the maximum light intensity direction when there is no obstruction, and the maximum light intensity direction after being blocked by the lamp body is referred to as the actual maximum light intensity direction below) and the substrate plane 1'. When installed and used, the cavity opening is downward, and the lowest point of the straight edge of the cavity is not higher than the lowest point of the lens 3, so that the light refracted by the lens 3 will not be directly emitted from the LED lamp 101 to the side of the road in a horizontal upward direction.

[0006] The above substrate may be an aluminum substrate, a copper substrate or a substrate of other materials. The following description will take an aluminum substrate as an example.

[0007] It should be noted that the cavity mentioned here can degenerate into a partial shielding surface, which plays a role in shielding the light emitted by the LED lamp 101 and directed toward the straight edge of the cavity toward the side of the road. It can even be combined with other surrounding elements (such as guardrails when embedded in guardrails) to play a role in shielding the light emitted by the LED lamp 101 and directed toward the straight edge of the cavity toward the side of the road. For the sake of convenience, we still call it a "cavity". Unless otherwise specified, the cavity mentioned below refers to the cavity in this expanded sense.

[0008] The LED lamp 101 has an important design parameter: the maximum installation inclination angle β, which is determined as follows: according to the preset usage scenarios of the lamp 101, the minimum installation height H and the maximum effective lighting width L of each usage scenario are determined. There is an angle whose cotangent value is equal to H / L. This angle is the angle between the maximum light intensity direction 4 of the light source 2 after refraction by the lens 3 and the road surface in the usage scenario (unless otherwise specified, all road surfaces mentioned in this article are horizontal). The minimum value of the above angles for all usage scenarios, that is, the minimum value of the angle between the maximum light intensity direction 4 and the horizontal plane when in use, is as follows: Figure 1 The angle between the maximum light intensity direction 4 of the LED lamp 101 of the lens 3 and the light source 2 and the aluminum substrate plane 1' is determined, as shown in FIG. Figure 1 The shown one is denoted as α, β=α-γ.

[0009] When the LED lamp 101 is installed at the maximum installation inclination angle β (at this time, the cavity opening is downward), the straight edge of the cavity and the lowest point of the lens 3 are on the same horizontal plane, that is, Figure 1 The horizontal plane 6 shown. When the LED lamp 101 is installed and used, the inclination angle cannot exceed the maximum installation inclination angle β, otherwise the lowest point of the lens 3 will be lower than the straight edge of the cavity, and the refracted light here will be directly emitted horizontally upward, which cannot play a strict anti-glare effect.

[0010] Supplementary explanation of the principle of defining the maximum effective illumination width L: the light beam is inclined toward the road surface, and the farther the distance, the smaller the inclination angle (this inclination angle refers to the angle between the light direction and the road surface). At a position farther away from the road surface pointed to by the maximum light intensity direction 4, the inclination angle of the light emitted by the lens 3 to that position is smaller than the inclination angle of the maximum light intensity direction 4 pointing to the effective maximum width road surface position. The light intensity itself in this emission direction is also decreasing. Under the dual effects, the illumination effect of the light beam on the road surface decreases rapidly. Therefore, in order to ensure that the illumination of the road surface by the lamp 101 meets the uniformity requirements of the national road lighting specifications, the maximum effective illumination width of the lamp 101 is set to: H*ctgγ.

[0011] It should be noted that the above installation height H is the vertical distance from the center O of the LED light source to the road surface, and the effective maximum lighting width L is the length of the projection of the ray segment at the road surface position pointed to by the direction 4 of the strongest light intensity after deflection by the lens 3, with the center O of the LED light source as the starting point. The position pointing to the road surface is also related to the spacing of the lamps 101 and the light intensity density in the plane of the maximum light intensity direction 4 after refraction by the lens 3. Therefore, L is a value determined by repeated experimental verification under the guidance of principles.

[0012] In particular, for a road surface inclined relative to the horizontal plane, the maximum effective lighting width L and installation height H need to consider the actual horizontal distance and vertical distance relative to the lamp 101 at the maximum effective width on the road surface as the maximum effective lighting width L and installation height H, and there is no other difference.

[0013] It should also be noted that, since the lens 3 cannot be regarded as a strict point light source, the so-called maximum light intensity direction 4 itself is an approximate concept, which is mainly affected by the selected lens 3. Since the LED light source 2 is not a strict point light source either, the selection of the LED light source 2 will also have a slight effect on the maximum light intensity direction 4. In addition, the maximum effective illumination width is particularly sensitive to the value of the maximum installation angle β. Therefore, all design conclusions drawn from the principle analysis are only an approximation of the actual lamp 101. When designing specifically, it is necessary to take the principle conclusion as the starting point and repeatedly verify the design prototype in the predetermined usage scenario to give the exact design parameters. This method runs through the entire design process and will not be elaborated one by one.

[0014] In order to design the LED lamp 101 to be smaller, the straight edge of the cavity needs to be closer to the light source 2, but the straight edge of the cavity cannot be too close to the light source 2, otherwise it will block the light emitted in the direction of maximum light intensity 4, greatly reducing the lighting efficiency, which is unacceptable.

[0015] like Figure 1 As shown, starting from the upper tilted edge P of the lens 3, the ray 7 pointing to the direction parallel to the maximum light intensity direction 4 and the horizontal line 6 have an intersection point B. The straight edge of the cavity is set at B, and all the light rays directly directed to the maximum light intensity direction 4 after being refracted by the lens 3 will not be blocked by the cavity. This is the position where the straight edge of the cavity is closest to the light source 2 without losing the effective lighting intensity.

[0016] It should be further explained here that, in theory, a straight line is drawn from the starting point of ray 7 to the maximum width of the road surface to be illuminated (within the same vertical section), and the intersection of this straight line and straight line 6 is assumed to be B'. The position of B' is slightly offset inward compared to B. If the straight edge of the cavity is set at any position between B and B', from the light path diagram, the light refracted from the lens directly illuminating the maximum width of the road surface will not be blocked, and thus will not cause the loss of effective lighting flux. Therefore, B' is the real best choice. However, considering that the positions of B' and B are extremely close, usually, the length of BB' is less than the design accuracy. Therefore, B' and B can be designed without distinguishing. Point B can refer to any point between BB'. Because the distance between B and B' is within the design accuracy, it is considered that their positions are substantially the same, which is the best choice for taking into account both the effective luminous flux not being lost by shading and the minimum LED lamp 101 size meeting the shading requirements.

[0017] In a specific use scenario where the LED lamp 101 needs to be embedded in the guardrail 102, the minimum size of the LED lamp 101 in the straight edge position of the cavity may still be too large. It is necessary to pursue the extremely small size of the low-position lighting LED lamp 101 under strict anti-glare conditions, of course, this is achieved at the expense of some effective lighting luminous flux.

[0018] Under the premise of selecting the polarized lens 3 and the LED light source 2, the maximum light intensity direction 4 is determined (mainly determined by the polarized lens 3, and the LED light source 2 will also have a slight influence on the maximum light intensity direction 4 because it is not a strict point light source). The shielding angle in the previous best choice of the straight edge of the cavity does not block any light emitted from the lens 3 pointing to the maximum light intensity direction 4, and thus will not reduce the original maximum light intensity 4 The direction of the road is illuminated. Now, in order to make the lamp smaller, it is necessary to reduce the distance between the straight edge of the cavity and the light source. For example, it is necessary to change the straight edge of the cavity to be set at Figure 1At this time, part of the light emitted from the lens 3 and pointing to the maximum light intensity direction 4 is blocked. After the blocking, the spatial distribution of the luminous flux changes. This change will cause the actual maximum light intensity direction after the blocking to change accordingly. In fact, the actual maximum light intensity direction will move downward after the blocking, so simply changing the straight edge of the cavity to set at Figure 1 The solution at C cannot meet the maximum effective illumination width requirement, because the effective illumination width of the LED lamp 101 designed in this way becomes smaller, and cannot meet the predetermined maximum effective illumination width requirement. Therefore, it is necessary to further extend the straight edge of the cavity at C downward to increase the shielding angle, and at the same time correspondingly expand the maximum installation angle β, so that the actual maximum light intensity direction points to the position of the maximum illumination road width when installed at the maximum installation angle β.

[0019] When designing for miniaturization, another factor needs to be considered, that is, the shielding angle cannot be arbitrarily expanded. First, the determined shielding angle cannot block the maximum light intensity direction 4, otherwise it will cause a serious loss of luminous flux and fail to meet the requirements of road lighting efficiency. Therefore, there is a limit to making the LED lamp 101 smaller. When the preset size cannot meet the light efficiency requirements, that is, if the solution of setting the straight edge of the cavity at the vertical section at C is ultimately verified to be unfeasible, we can only select another point between BC for re-verification, and gradually approach the possible position of the straight edge of the cavity to make the LED lamp 101 smaller.

[0020] In addition, if the LED lamp 101 needs to be made smaller, the maximum installation angle β should be designed to just meet the requirements of the usage scenario. Otherwise, if a larger maximum installation angle β is designed, the lamp 101 is applicable to a wider range of usage scenarios, but in principle Figure 1 It is not difficult to find that, with other factors remaining unchanged, as the maximum installation inclination angle β increases, the size of the lamp 101 will also increase, which is contrary to the demand for making the LED lamp 101 smaller. Of course, if the size of the lamp can be accepted to be slightly larger, the maximum installation inclination angle β can be designed to be slightly larger to enhance the adaptability of the lamp 101 to more usage scenarios.

[0021] After determining the position of the straight edge of the cavity, the other designs of the LED lamp 101 can be conventionally carried out. In particular, the shape of the lamp 101 can be asymmetrically designed according to the use environment, especially in the scene of embedding in the guardrail 102, so that the lamp 101 can better fit the external environment. The LED light source 2 is placed on the other side away from the straight edge of the cavity. Of course, this asymmetrical design can also be used in other scenes.

[0022] The low-level road lighting system constructed by using the LED lamp 101 of the present invention blocks the part of the light refracted by the lens 3 that is directed upward horizontally through the cavity of the LED lamp 101, and the upward luminous flux is composed of stray light caused by diffuse reflection. The upward luminous flux ratio is close to 0%, which fundamentally solves the glare problem. The straight edge of the cavity of the LED lamp 101 should be straight and parallel to the straight line of the center arrangement of the light source, so that the effective luminous flux is not blocked in the anti-glare state. If the design is deliberately degraded, the straight edge of the cavity is designed to be not so straight, and even slightly tilted during installation, the anti-glare lighting effect can be achieved in the use scenario where the width of the road to be illuminated is limited, it does not need to be installed at the maximum installation angle, or the lighting efficiency requirement is not so high. This deliberate degraded design is essentially the same as the present invention and is also within the protection scope of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a cross-sectional schematic diagram perpendicular to the road direction.

[0024] Figure 2 1 is a diagram of a lamp embodiment.

[0025] Figure 3 This is the lens light distribution diagram of Example 2.

[0026] Figure 4 It is a stereoscopic view and a cross-sectional view of the LED lamp embedded in the guardrail.

[0027] Figure 5 This is the front view of the LED lamp embedded in the guardrail installation.

[0028] Figure 6 This is a schematic diagram of the single-sided embedded installation of LED lamps on the road.

[0029] Figure 7 This is a schematic diagram of the embedded staggered installation of LED lamps on both sides of the road.

[0030] Figure 8 This is a schematic diagram of the embedded symmetrical installation of LED lamps on both sides of the road.

[0031] Fig. 9 This is the front view of the LED lamp pole installation.

[0032] Fig.10 It is a stereoscopic view and a cross-sectional view of the LED lamp pole installation.

[0033] Reference numerals

[0034] 1. Substrate / aluminum substrate, 1', substrate plane / aluminum substrate plane, 2. LED light source, 3. polarized lens, 4. direction of strongest light intensity, 5. horizontal plane 1, 6. horizontal plane 2 (in the vertical section, it also refers to the straight line 6 connecting AB in the figure), 7. Rays parallel to the inner edge of the lens and the direction of maximum light intensity, 8. shielding plate 1, 9. shielding plate 2, O, center of light source, P upper tilted edge of lens, A, cavity straight edge A, B, cavity straight edge B, C, cavity straight edge C, α, direction of maximum light intensity and aluminum substrate Angle of the plane, β, maximum installation deflection angle (angle between the aluminum substrate plane and the horizontal plane), γ, angle between the maximum light intensity direction and the horizontal plane, 10, metal shell (extended from the radiator, and at the same time to accommodate the cavity, the bottom edge of the side indicated by the number 10 is the straight edge of the cavity), 11, lens mounting bracket, 12, transparent lampshade, 13, bracket for fixing the lamp (embedded in the guardrail scene), 13', bracket for fixing the lamp (under the condition of column installation), 101, LED lamp, 102, guardrail, 103, column. DETAILED DESCRIPTION

[0035] Example 1, a strictly anti-glare LED lamp with straight edges of the cavity.

[0036] refer to Figure 2 The LED lamp 101 includes an aluminum substrate 1, LED light sources 2 arranged in a row on the aluminum substrate 1, polarized lenses 3 covering the LED light sources 2 one by one, a lens mounting bracket 11, a transparent lampshade 12, a metal shell 10 extending from a heat dissipation device into a cavity, and a bracket 13 for fixing the lamp. As shown in the figure, each part is connected by screws or glued.

[0037] Among them, the lens mounting bracket 13 is a pressing frame, and the lens 3, the LED light source 2 and the aluminum substrate 1 are fixed to the metal shell 10 with screws. The angle between the light-emitting central axis of the lens 3 and the road surface direction can be adjusted according to the actual application scenario, which can make the light distribution on the road surface more uniform, and can also make the light deflected at an angle in the driving direction when it is emitted, so that the light emission direction points to the front of the driver or pedestrian, making the LED lamp 101 appear visually lower in brightness.

[0038] The transparent lampshade 12 may be made of tempered transparent glass or high-transparency plastic.

[0039] The transparent lampshade 12 is bonded to the metal housing 10 with waterproof glue, or fixed to the metal housing 10 with screws using waterproof washers; the lamp body power input line is fixed with a waterproof connector to form a sealed cavity inside the lamp body to prevent water from entering and rendering the entire lamp inoperable.

[0040] The lowest edge of the side pointed by the number 10 of the metal shell 10 is the straight edge of the cavity. In the assembled state, the angle between the plane formed by the straight edge of the cavity and the lowest edge of the lens 3 and the plane where the aluminum substrate 1 is located is the maximum installation inclination angle. The maximum light intensity direction 4 of the lamp 101 is jointly determined by the selected lens 3 and the LED light source 2. When the lamp 101 is installed at the maximum installation inclination angle, the maximum light intensity direction 4 points to the farthest position of the road surface that needs to be effectively illuminated. Of course, pointing to a farther position can also meet the lighting requirements.

[0041] In order to reduce the size of the lamp 101, the metal housing 10 can be designed asymmetrically, and the aluminum substrate 1 is placed away from the straight edge of the cavity.

[0042] It should be noted that when the lamps 101 are installed on both sides of a wider road, the structures of the lamps 101 on both sides are axially symmetrical and not completely consistent.

[0043] In special cases, the LED lamp 101 has only one LED light source 2, and the placement direction of the light source 2 and the lens 3 is designed to be the aforementioned light source center arrangement direction, and the rest is no different and also within the protection scope of the present invention.

[0044] Example 2: Conventional three-lane scene, LED lamp with miniaturized design that is easy to embed into road guardrail installation.

[0045] In addition to the features of the first embodiment, the LED lamp 101 of the second embodiment has the following features:

[0046] Taking a conventional three-lane road as an example, the road width is 11.25 meters (each lane is 3.75 meters wide), LED lamps 101 are installed on both sides of the road, and a large polarized lens 3 available on the open market is used. After being deflected by the lens 3, the angle between the maximum light intensity direction 4 and the aluminum substrate plane 1' is 26 degrees. The shape of the lens 3 is as follows: Figure 1 As shown, the light distribution diagram of lens 3 is as follows Figure 3 shown.

[0047] The installation height of lamp 101 is 1.1 meters (the installation height of 1.1 meters refers to the height of the straight edge of the cavity, the center of the light source is about 0.02 meters away from the straight edge of the cavity, and therefore the height of the center of the light source from the ground is about 1.12 meters), the maximum light intensity direction 4 points to the center of the road, the installation spacing between lamps is 3 meters, and the maximum illumination width is defined as 5.625+0.114 / 2=5.682 meters (considering that the diameter of the guardrail circular tube is 0.114 meters and the guardrail does not invade the road surface), and tgγ=0.1971 and γ=11.15 degrees are calculated. The theoretical calculation shows that the maximum installation inclination angle is 14.85 degrees, so that the maximum light intensity direction 4 can point to the center of the road. After verification in actual scenes, the actual design determines that the maximum installation inclination angle is 16.0 degrees, which can make the road surface illumination uniformity more ideal. This is the actual result of comprehensively considering the installation distance between lamps and the light intensity distribution after refraction of the selected lens.

[0048] After determining the maximum installation angle, press Figure 1 The position of the straight edge of the cavity is determined by point B, and other parameters and components are the same as those in Example 1, thereby obtaining a conventional three-lane scene LED lamp 101 with a miniaturized design that is easy to embed in the road guardrail 102 for installation. The situation after the lamp 101 is embedded in the guardrail 102 is as follows Figure 4 As shown, the fixing screws adopt a sunken structure to avoid protrusion on the surface of the guardrail.

[0049] Considering the size limitation of the guardrail 102 itself, the LED lamp 101 may still not be completely embedded in the guardrail 102, or completely embedding the lamp 101 in the guardrail 102 may cause the opening of the guardrail 102 to be too large, affecting the strength of the guardrail 102. The LED lamp 101 may be partially protruded on the side of the guardrail 102 away from the road.

[0050] At this time, one can also consider pursuing the position of the straight edge of the cavity determined by the ultimate minimum size, at the expense of the effective luminous flux, such as the method described in the invention content, designing the size of the LED lamp 101 to be smaller, so that the LED lamp 101 is completely embedded in the guardrail 102, or making the protruding part of the LED lamp 101 on the outside of the guardrail 102 smaller. The maximum allowable luminous flux loss in this usage scenario is 22%. This requirement determines the lower limit of pursuing the ultimate minimum size.

[0051] The above situations are all manifested as follows: there is a unique tangent plane 7' parallel to the central arrangement straight line of the LED light source 2 between the straight edge of the cavity and the outer edge P of the lens 3 (on the side of the polarization direction), and the angle between the tangent plane 7' and the aluminum substrate plane 1' is not less than the angle between the maximum light intensity direction 4 and the aluminum substrate plane 1'.

[0052] Embodiment 3, low-position road lighting system (single-side lighting) in which LED lamps are embedded in guardrails.

[0053] like Figure 5As shown: the relative position of the lamp 101 in the guardrail 102. Figure 6 As shown, the lamp 101 is arranged on a guardrail 102 on one side of a single lane road, and the arrangement height is 1.1 meters.

[0054] Embodiment 4, a low-position road lighting system with LED lamps embedded in guardrails (symmetrical lighting arrangement on both sides).

[0055] like Figure 7 As shown, the lamps 101 are symmetrically arranged on the guardrails 102 on both sides of the two-lane road, with a height of 1.1 meters. The lamp structures on both sides are axially symmetrical.

[0056] Example 5, a low-position road lighting system with LED lamps embedded in guardrails (staggered lighting on both sides).

[0057] like Figure 8 As shown, the lamps 101 are staggeredly arranged on the guardrails 102 on both sides of the three-lane road, with a height of 1.1 meters. The lamp structures on both sides are axially symmetrical.

[0058] Embodiment 6, a low-position road lighting system in which LED lamps are fixed on pillars.

[0059] like Fig. 9 , Fig.10 As shown, the LED lamp 101 is fixed on a column 103 beside the road, and the installation height is 1.1 meters. Similar to the case of embedding the guardrail, the lamp can be installed on one side or on both sides.

[0060] Furthermore, the interior of the cavity is arranged in black and lined with a rough diffuse reflective surface to further reduce eye discomfort caused by excessively bright diffuse stray light.

[0061] This lamp can also be used on roads with mixed traffic or in car-free environments. In particular, for environments with young children, the installation height should be lower than the direct eye height of the young children when walking, such as less than 60 cm.

[0062] In addition to being embedded in guardrails and fixed to poles, this lamp also has other installation methods, such as being fixed to the outside of guardrails.

[0063] Unless otherwise specified, roads in this manual include highways, bridges, squares, internal roads, etc.

[0064] The above implementation methods cannot limit the protection scope of the present invention. Any substantially identical changes made by professionals in the professional and technical field without departing from the overall concept of the present invention, or any degraded designs that intentionally pursue differences, are still within the scope of the present invention.

Claims

1. An LED lamp for low-position road lighting, comprising an LED light source on a substrate, polarized lenses covering the LED light source one by one, a transparent lampshade, and a metal radiator, characterized in that: The centers of the LED light sources are arranged in a straight line, the substrate is placed in a cavity, the lower edge of the outer side of the cavity on the polarization direction side is a straight edge of the cavity parallel to the straight line of the center arrangement of the light sources, the angle between the plane formed by the straight line of the center arrangement of the LED light sources and the straight edge of the cavity and the plane of the substrate is smaller than the angle between the maximum light intensity direction and the plane of the substrate when there is no obstruction, the cavity opening is downward when installed and used, and the lowest point of the straight edge of the cavity is not higher than the lowest point of the lens, so that the light refracted by the lens will not be emitted directly from the LED lamp to the side of the road in a horizontal upward direction.

2. The LED lamp as described in claim 1, wherein there is a unique tangent plane parallel to the straight line of central arrangement of the LED light sources between the straight side of the cavity and the outer edge of the lens on the polarization direction, and the angle between the tangent plane and the substrate plane is not less than the angle between the maximum light intensity direction and the substrate when there is no obstruction.

3. The LED lamp as described in claim 1, wherein the substrate can be an aluminum substrate, a copper substrate, etc.

4. The LED lamp as claimed in claim 1, wherein the LED light source is placed on a side of the cavity away from a straight side of the cavity.

5. The LED lamp according to any one of claims 1, wherein the angle of the lens is independently adjustable within the plane of the substrate. The LED lamp as claimed in claim 1 , wherein the cavity is formed by expanding the heat sink.

7. The LED lamp as claimed in claim 1, wherein the interior of the cavity is a black diffuse reflection surface.

8. The LED lamp as claimed in claim 1, wherein the transparent lampshade is made of tempered transparent glass or high-transparency plastic.

9. A low-position road lighting system consisting of LED lamps as described in claims 1-7, wherein the installation height of the LED lamps is not higher than 1.1 meters from the road surface; when the road to be illuminated is a single lane, the LED lamps are installed at intervals on one side of the road; when the road to be illuminated is three lanes or more, the LED lamps can be installed at intervals on both sides of the road in a symmetrical or staggered manner; when the road to be illuminated is two lanes, the LED lamps can be installed on one side or both sides.

10. The low-position road lighting system composed of the LED lamp as claimed in claim 8, wherein when the LED lamp is embedded in the road guardrail for installation, the upper edge of the opening of the guardrail for accommodating the LED lamp does not block the light refracted by the lens of the LED lamp and emitted directly below the straight edge of the cavity, and the LED lamp does not protrude from the outermost part of the guardrail on the side of the guardrail close to the road. When the LED lamp is too large to be completely embedded in the guardrail, the LED lamp is allowed to be installed partially protruding on the other side of the guardrail.

11. A low-position road lighting system composed of LED lamps as described in claims 1-7, wherein the LED lamps are fixed on pillars on the road side.

Images