CN100590346C

CN100590346C - LED road lamp

Info

Publication number: CN100590346C
Application number: CN200710125625A
Authority: CN
Inventors: 钱可元; 罗毅
Original assignee: Shenzhen Graduate School Tsinghua University
Current assignee: Shenzhen Graduate School Tsinghua University
Priority date: 2007-12-29
Filing date: 2007-12-29
Publication date: 2010-02-17
Anticipated expiration: 2027-12-29
Also published as: CN101220913A

Abstract

The invention discloses an LED street lamp which comprises an LED light source and is characterized by comprising at least two pairs of different lateral collimation reflection surfaces, wherein, onepair of lateral collimation reflection surfaces is used for compressing light in the width direction of an irradiated plane rectangle through reflection, the other pair of lateral collimation reflection surfaces are used for extending the light along the length direction of the irradiated plane rectangle by reflection. Due to being provided with two pairs of lateral collimation reflection surfaceswhich are respectively used for compressing the light along the width direction of an irradiated plane rectangle through reflection and extending the light in the length direction of the irradiated plane rectangle by reflection, the invention can form a rectangular lighting area on a roadway and meet the lighting requirements of roads.

Description

A kind of LED street lamp

Technical field

The present invention relates to optical system, relate in particular to a kind of LED street lamp.

Background technology

The transitional street lamps light source adopts high pressure sodium lamp, high-pressure sodium lamp etc. mostly, and consumed power is bigger, the operating voltage height, start-up time is slower, is not easy to the brightness of street lamp is regulated in different time sections, and bulb service life is short, make that the fluorescent tube turnover rate is too high, maintenance cost significantly rises.

LED is as a kind of novel solid light source, compares with traditional light source to have a lot of advantages, and as energy-conservation, therefore characteristics such as environmental protection is easy to regulate, and the life-span is long are highly suitable for the light source as various lighting fields, such as the light source of city illumination light fixture.

Roadway lighting system is different from general lighting, and its illuminated field is a rectangular area.According to the national highway lighting criteria, satisfy the average illumination of on the plane of illumination of a rectangle (generally being 10 meters X35 rice) and the uniformity of illumination.And most of place needs in the real road illumination also is the illumination hot spot of a bar shaped, such as corridor, runway, pavement, various traffic routes etc.

The present LED street lamp that occurs, power is from tens to hundreds of watts, often all form by a plurality of LED, because its distribution of light that LED itself sends is approximately lambert's type, be that light intensity is the cosine issue, the hot spot that forms on the road surface is a uneven round spot normally: the center is very bright, and very fast in radial decay.The circular light field of Xing Chenging will be unfavorable for the utilization of luminous energy like this, can't satisfy the lighting requirement of rectangular area.

Summary of the invention

Technical problem to be solved by this invention provides a kind of LED street lamp that can form a rectangular illumination zone on the road surface.

LED street lamp of the present invention comprises led light source, it is characterized in that, also comprise at least two pairs of different side collimated reflected faces, wherein an offside collimated reflected face is used for will contracting at the optical pressure of the width of plane of illumination rectangle by reflection, and an other offside collimated reflected face is used for will stretching at the light of the length direction of plane of illumination rectangle by reflection; Wherein, the direction of described width along the plane of illumination rectangle is a Y direction, direction along the length of plane of illumination rectangle is an X-direction, perpendicular to X, the direction on Y plane is a Z-direction, a described offside collimated reflected face that will stretch at the light of the length direction of plane of illumination rectangle is near light source, its core is outstanding to Z-direction near the light source place, a described offside collimated reflected face that will contract at the optical pressure of the width of plane of illumination rectangle is away from light source, its outward flange is the straight line along X-direction, and inward flange is connected with the outward flange of an offside collimated reflected face of approaching light source.

Described LED street lamp also comprises at least one opposite end reflecting surface.Can limit the distribution of the maximum angle and the rim ray of outgoing like this.

The direction of described width along the plane of illumination rectangle is a Y direction, direction along the length of plane of illumination rectangle is an X-direction, perpendicular to X, the direction on Y plane is a Z-direction, a described offside collimated reflected face that will stretch at the light of the length direction of plane of illumination rectangle is near light source, its core is outstanding to Z-direction near the light source place, a described offside collimated reflected face that will contract at the optical pressure of the width of plane of illumination rectangle is away from light source, its outward flange is the straight line along X-direction, and inward flange is connected with the outward flange of an offside collimated reflected face of approaching light source.This is the embodiment of the different side collimated reflected face of preferable two couple.

A described offside collimated reflected face that will contract at the optical pressure of the width of plane of illumination rectangle is the 3 D stereo surface, and the curve of the projection on its horizontal profile, on the side surface section is any in the following curve: straight line, circle, hyperbola, ellipse, parabola, curvilinear equation are at the high order curve more than 3 times; Or in the above-mentioned curve any more than two or three the splicing.The surface of emission of these above-mentioned shapes can reach the purpose that the optical pressure at the width of plane of illumination rectangle is contracted.

The offside collimated reflected face that the light of described length direction with the plane of illumination rectangle stretches is to be not less than 90 ℃ curved surface or inclined-plane with Z axle clamp angle.Angle is less than 90 ℃ of ejaculations that are unfavorable for light, and this offside collimated reflected face is selected the inclined-plane, can make simplicity of design; Select curved surface, design is complicated, but can control the distribution of light better.

Described end reflecting surface is curved surface or inclined-plane.Select the inclined-plane, can make simplicity of design; Select curved surface, design is complicated, but can control the distribution of light better.

Described two pairs of different side collimated reflected face, pair of end reflectings surface are combined into one group of optics, and described optics is many groups, and every group of respectively corresponding led light source organized optics more and formed splicing and combining of matrix.The optics of the street lamp of this LED is many groups.

Described led light source is single or multiple led chip combinations.This is to have under the situation of many group optics, and the led light source of every group of optics correspondence is single or multiple led chip combinations.

Led light source is single or multiple led chip combinations, and combination back led chip integral body is corresponding to two pairs of different side collimated reflected faces, pair of end reflecting surface.The optics of the street lamp of this LED only is one group, but corresponding led light source is single or multiple led chip combinations.

Described LED street lamp also comprises package lens one time, and led chip places the bottom of a package lens and is packaged into led module with a package lens.One time package lens can adopt sphere or non-spherical lens, is packaged into the light extraction efficiency that can make the led light source chip behind the led module with led chip and improves, and adopts non-spherical lens can make the original Lambertian source of outgoing light ratio have bigger outgoing half-angle.

The present invention is owing to be provided with two pairs and be respectively applied for by reflection and will contract and be used for the side collimated reflected face that will stretch at the light of the length direction of plane of illumination rectangle by reflection at the optical pressure of the width of plane of illumination rectangle.So can on the road surface, form a rectangular illumination zone, satisfy the requirement of road lighting.

Description of drawings

Fig. 1 is the perspective view of LED street lamp among the embodiment 1;

Fig. 2 is the vertical view of LED street lamp among the embodiment 1;

Fig. 3 is the sectional view (side view) of the Y-Z coordinate plane of LED street lamp among the embodiment 1;

Fig. 4 is the vertical view that LED road lamp system light path of light is analyzed among the embodiment 1;

Fig. 5 is that LED road lamp system emergent light changes schematic diagram at X-Z perspective plane upper angle among the embodiment 1;

Fig. 6 is the schematic diagram of LED road lamp system end reflecting surface reflection ray among the embodiment 1;

Fig. 7 is the schematic diagram that many groups optics of LED street lamp among the embodiment 2 is combined into array structure;

Fig. 8 is the schematic diagram of LED road lamp system end reflecting surface reflection ray among the embodiment 2.

Fig. 9 is the arrangement architecture schematic diagram of a plurality of led chip encapsulation of single group optics correspondence among the embodiment 3.

Wherein: 1, led light source, 2, once encapsulate non-spherical lens, 3, reflecting surface, 4, emitting surface, 5, reflecting surface, 6, reflecting surface, 7, fluorescent material, 8, the end reflecting slant, 9, the end reflecting slant, 10, light, 11, the end reflecting curved surface, 12, the end reflecting curved surface, 15, light, 16, light, 25, light, 26, light, 27, light, 28, light, 35, light, 36, light, 37, light, 38, light, 41, light, 42, light, 43, light, 45, light, 46, light, 51, light, 52, light, 53, light, 55, light, 56, light, 57, light, 65, light, 66, light, 67, light.

The specific embodiment

The invention will be further described below in conjunction with accompanying drawing and preferred embodiment.

Design principle:

If above the rational assign road face of the light of wanting led chip to send, on the road surface, form the rectangular region of a uniform illumination, then need the light that led chip the sends design that collimates.

At the collimation design aspect of non-imaging, refractive surface and reflecting surface are two kinds of means that adopt usually.When needing the light angle of deviation smaller, can adopt refractive surface to finish the deviation task; When the angle that needs deviation light surpasses the converging power of refractive surface, then all adopt reflecting surface to finish the deviation task.In general given irradiated plane; in the photodistributed luminous energy transmission optics of the given irradiation system; usually use one or more lens devices and finish the task of light field wavefront variation; because the target light field is a rectangle, optics also will inevitably be expanded becomes the three-dimensional optical of non-rotating symmetry system.Yet general lens combination based on refraction principle, will inevitably introduce the absorption loss of all kinds of interface loss and lenticular body material, simultaneously under the approximate situation of light source deviation point light source, since the light on expansion light source border be mapped to plane of refraction the time its shooting angle depart from the shooting angle of light source center light, and the optical effect face designs at the light of light source center point often, the deviation of this angle of emergence can cause inner total reflection, when the optical field distribution off-design is required the light efficiency of system is descended greatly.Then can avoid and alleviate the problems referred to above for reflective optical system.The reflecting surface optical system will be than the accurate transparent refractor of aspheric surface system all easy aspect the industrial processes moulding simultaneously, and cost is lower.

The limited angular range of the light transmission of sending in the solid angle to, and to make the illumination in the rectangle light field of target even, therefore new three-dimension curved surface method for designing is adopted in the design of curved surface, both according to law of conservation of energy, with the energy on light source plane and the energy binned on illumination plane is some zonules of energy correspondent equal, then at an emergent ray and optional between the point on the illumination plane of energy correspondent equal with it a bit as initial point of lens surface to be found the solution, energy binned result in conjunction with light source and illumination plane, utilization iterates coordinate and the normal vector that the method for finding the solution solves all discrete points of lens surface, thereby determines a surface of emission surface.The detailed method of this part can be referring to the Chinese invention patent application, and publication number is: CN1928624A.

Embodiment 1

Referring to Fig. 1, Fig. 2, the LED street lamp comprises led light source in the present embodiment, and led light source is a plurality of, and each led light source is a led chip 1, and the led chip size can be models such as 350um * 350um or 1mm * 1mm, is coated with fluorescent material 7 on the led chip.

Each led chip place the aspheric once diversity lens 2 of encapsulation the bottom and with once encapsulate the diversity lens packages and become led module.Each led chip is to there being one group of optics, this group optics comprises two pairs of different side collimated reflected faces, pair of

end reflecting slant

8,9, wherein an offside collimated reflected

face

3,4 is used for will contracting at the optical pressure of the width of plane of illumination rectangle by reflection, and an other offside collimated reflected

face

5,6 is used for will stretching at the light of the length direction of plane of illumination rectangle by reflection.The direction of described width along the plane of illumination rectangle is a Y direction, direction along the length of plane of illumination rectangle is an X-direction, direction perpendicular to X, Y plane is a Z-direction, side collimated reflected

face

5,6 is near led module, side collimated reflected face the 5, the 6th, the angle that forms with the Z axle is not less than 90 ℃ curved surface or inclined-plane, its core is outstanding to Z-direction near the led module place, described side collimated reflected

face

3,4 is away from light source, its outward flange is the straight line along X-direction, and inward flange is connected with the outward flange of side collimated reflected

face

5,6.

For ease of explanation, in this hypothetical target light field is one narrow and at a wide rectangle of directions X in the Y direction, also promptly require the outgoing half-angle of light in the Y direction is controlled at θ 0 scope and in directions X should be controlled at Ψ 0 scope, θ 0＜Ψ 0, and led light source is a Lambertian source, and therefore requirement will collimate to light at directions X the Y direction is then required light to the wide-angle deviation.

Reflecting

surface

3,4 and 5,6 two pairs of curved surfaces combine the lateral reflection face and reach the deviation requirement of directions X to light, and

curved surface

3,4 is quadratic surfaces of a distortion, and its effect is that light is collimated in the Y

direction.Curved surface

5,6 is the curved surfaces that the centre goes out to the Z aixs cylinder, and its effect is being mapped to light on it to the positive negative direction deviation of X, promptly increasing the X-direction component of emergent ray, to form the big angle of emergence of directions X, as shown in Figure 4.

The reflecting surface 3 of described lens combination, the curve of the projection 4 on horizontal profile, on the side surface section is any in the following curve: straight line, circle, hyperbola, ellipse, parabola, curvilinear equation are at the high order curve more than 2 times, or any two or more is spliced in the above-mentioned

curve.Reflecting surface

5,6 the curves of projection on horizontal profile are any in the following curve: straight line, circle, hyperbola, ellipse, parabola, curvilinear equation are at the high order curve more than 2 times, or any two or more is spliced in the above-mentioned curve.

At the light of the directions X angle of emergence greater than Ψ 0, with another symmetrical end reflections inclined-

plane

8,9 is reflected it among the present invention desired by in the irradiation angle scope, with control by length according to the rectangle light field.As shown in Figure 6.

For ease of understanding, be that lamp is 10 meters from the plan range of quilt photograph with the target that designs, the width in illuminated zone is 10 meters, when length is 35 meters, θ 0=26.5 degree, Ψ 0=60.3 degree.Can determine marginal dimension, height and the position of each reflecting surface thus, the height h1 of reflecting

surface

5,6 gets 0.5-0.9 times of its middle minimum distance D.

Brief description is the light emission route of led chip once.Referring to Fig. 3, Fig. 4, Fig. 5, Fig. 6,

Led chip 1 is positioned on the central point of lens combination bottom.The light of led chip 1 is after the surface refraction outgoing of lens 2, and the light that incides reflecting surface will be subjected to different reflecting effects respectively in X, Y direction;

In the Y direction, the refraction of part light 15 (16) scioptics 2 becomes 25 (26), after the process reflection of reflecting

surface

5,6 earlier is light 35 (36), be reflected into emergent ray 45 (46) through reflecting

surface

4,3 again, the refraction of another part light 17 (18) scioptics 2 becomes the only reflection of

process reflecting surface

4,3 of light 27 (28), become light 37,38, also has part light without direct outgoing of reflecting surface such as light 10, the final angle of emergence of these emergent lights all is limited in the half-angle range Theta 0 of a setting, reaches the purpose of restriction light field width.As shown in Figure 3.

At directions X, part light is through passing through the reflection of reflecting

surface

4,3 again after the reflection of reflecting

surface

5,6, as light 45 (46), another part light only passes through the reflection such as the light 37 (38) of reflecting

surface

4,3, these light are through after the effect of reflecting

surface

5,6,4,3, and emergent ray all can become big with the angle theta of Z axle on the XZ perspective plane, θ 4＞θ 3＞θ 2＞θ 1, the stronger luminous energy in center that makes LED be lambertian distribution spreads to wide-angle region.Shown in Fig. 4,5.

To high angle scattered light (Ψ＞Ψ 0) by lens 2 outgoing, adopt the pair of end reflecting slant to change its direction, make all emergent raies such as

light

55,56,57,58 and

reflection ray

65,66,67, the final angle of emergence all is limited in the half-angle scope Ψ 0 of a setting, reaches the purpose of restriction light field length.As shown in Figure 6.

Embodiment 2

Difference in the present embodiment is that the pair of end reflecting surface is a curved surface 11,12.The array that led light source is formed is placed along symmetry axis Z axial symmetry.As shown in Figure 7.Every family optics and one or several led chip are encapsulated as one group, organize matrix more and splice and combine use.For making the hot spot on the plane screen of far field is a rectangle, should make the direction of all the symmetry axis X of optical system and Y consistent or parallel during splicing.

As shown in Figure 8, reflecting

curved surface

11,12 reflexes to the opposite direction of X-axis to wide-angle (Ψ＞Ψ M) light by lens 2 outgoing, and the angle of emergence of

design rim ray

41,51 has just determined the maximum shooting angle Ψ 0 of system's directions X, Ψ 0＞Ψ M usually.Thereby guide all emergent lights as

light

42,43, and

emission light

52,53, all will be mapped in the illumination range of rectangle in far field or strip.

Embodiment 3

Referring to Fig. 9, difference in the present embodiment is that led light source is a plurality of led chip combinations, and combination back led chip integral body is corresponding to two pairs of different side collimated reflected faces, pair of end reflecting surface.The optics of the street lamp of this LED only is one group, but corresponding led light source is a plurality of led chip combinations.

In concrete enforcement, light source with lens 2 can be spherical mirror, also can be non-spherical lens.Light source also can or adopt planar package without lens, and these light that all just changed the light source outgoing distribute, and can be optimized according to these primary condition when the design reflectivity face.

The road lamp system of the present invention's design has than the higher light extraction efficiency of general refractor optical system, system is simple, be easy to large-scale production, applicable to advantages such as high power LED modules, can substitute transitional street lamps fully, applicable to the street lamp of highway, trunk roads, secondary distributor road, branch road illumination.Simultaneously, each optical system can form a complete light field in whole field of illumination, therefore can light source and lens simply be lined up array according to the concrete illumination requirement and the luminous flux level of light source, to satisfy different road surfaces to illumination requirement.The present invention compares with existing lighting engineering, has characteristics efficient, energy-conservation and flexible and convenient to use, and in the LED road lighting, there is wide application prospect in fields such as Landscape Lighting.

Though title of the present invention is the LED street lamp, in fact also can use indoorly, need the place of rectangular region illumination.If, also should be considered as falling into protection scope of the present invention so other people will use indoors with the LED lamp of spline structure.

Above content be in conjunction with concrete preferred implementation to further describing that the present invention did, can not assert that concrete enforcement of the present invention is confined to these explanations.For the general technical staff of the technical field of the invention; without departing from the inventive concept of the premise; can also make some simple deduction or replace; as: the end reflecting surface also can be the plane; led chip also can adopt non-divergent lens encapsulation etc., all should be considered as belonging to protection scope of the present invention.

Claims

1, a kind of LED street lamp, comprise led light source, it is characterized in that, also comprise at least two pairs of different side collimated reflected faces, wherein an offside collimated reflected face is used for will contracting at the optical pressure of the width of plane of illumination rectangle by reflection, and an other offside collimated reflected face is used for will stretching at the light of the length direction of plane of illumination rectangle by reflection; Wherein, the direction of described width along the plane of illumination rectangle is a Y direction, direction along the length of plane of illumination rectangle is an X-direction, perpendicular to X, the direction on Y plane is a Z-direction, a described offside collimated reflected face that will stretch at the light of the length direction of plane of illumination rectangle is near light source, its core is outstanding to Z-direction near the light source place, a described offside collimated reflected face that will contract at the optical pressure of the width of plane of illumination rectangle is away from light source, its outward flange is the straight line along X-direction, and inward flange is connected with the outward flange of an offside collimated reflected face of approaching light source.

According to the described LED street lamp of claim 1, it is characterized in that 2, described LED street lamp also comprises at least one opposite end reflecting surface.

3, according to the described LED street lamp of claim 1, it is characterized in that, a described offside collimated reflected face that will contract at the optical pressure of the width of plane of illumination rectangle is the 3 D stereo surface, and the curve of the projection on its horizontal profile, on the side surface section is any in the following curve: straight line, circle, hyperbola, ellipse, parabola, curvilinear equation are at the high order curve more than 3 times; Or in the above-mentioned curve any more than two or three the splicing.

According to the described LED street lamp of claim 1, it is characterized in that 4, the offside collimated reflected face that the light of described length direction with the plane of illumination rectangle stretches is to be not less than 90 ℃ curved surface or inclined-plane with Z axle clamp angle.

According to the described LED street lamp of claim 2, it is characterized in that 5, described end reflecting surface is curved surface or inclined-plane.

6, according to the described LED street lamp of claim 2, it is characterized in that described two pairs of different side collimated reflected face, pair of end reflectings surface are combined into one group of optics, described optics is many groups, every group of respectively corresponding led light source organized optics more and formed splicing and combining of matrix.

According to the described LED street lamp of claim 6, it is characterized in that 7, described led light source is single or multiple led chip combinations.

According to the described LED street lamp of claim 2, it is characterized in that 8, led light source is single or multiple led chip combinations, combination back led chip integral body is corresponding to two pairs of different side collimated reflected faces, pair of end reflecting surface.

According to the described LED street lamp of claim 7, it is characterized in that 9, described LED street lamp also comprises package lens one time, led chip places the bottom of a package lens and is packaged into led module with a package lens.