CN211780870U

CN211780870U - Lens unit, lens assembly and street lamp cap applied to wide-road working condition

Info

Publication number: CN211780870U
Application number: CN202020725194.2U
Authority: CN
Inventors: 畅育科
Original assignee: Zhuhai Jinsheng Lighting Equipment Co ltd
Current assignee: Zhuhai Jinsheng Lighting Equipment Co ltd
Priority date: 2020-05-01
Filing date: 2020-05-01
Publication date: 2020-10-27
Anticipated expiration: 2030-05-01
Also published as: CN211780870U9

Abstract

The utility model provides a lens unit applied to wide road working condition, the lens unit is provided with an inner cavity for accommodating a light-emitting device, and the lens unit comprises an incident surface positioned on the inner surface of the lens unit and an emergent surface positioned on the outer surface of the lens unit; when the light-emitting device is arranged on the lens unit, the projection of the center of the light-emitting device on the bottom plane of the lens unit is positioned on the short axis of the lens unit, and the distance L deviating from the geometric center of the bottom plane of the lens unit is more than 0 mm and less than or equal to 2 mm; the light beam emitted from the light emitting device is incident to the incident plane at an incident angle ranging from-60 degrees to 60 degrees, is refracted at a refraction angle ranging from-64.635 degrees to 68.325 degrees correspondingly, and is emitted from the emergent plane at an emergent angle ranging from-83.24 degrees to 84.23 degrees correspondingly, so that the light beam is effectively projected to a road surface after light distribution, and the illumination efficiency is effectively improved.

Description

Lens unit, lens assembly and street lamp cap applied to wide-road working condition

Technical Field

The utility model relates to a road lighting field especially relates to a be applied to wide road operating mode's lens unit, install the lens subassembly of a plurality of lens units and install the street lamp holder of lens unit.

Background

The LED lamp has the characteristics of long service life, power saving and the like, and is widely applied in various fields in recent years. Particularly, with the continuous implementation of national semiconductor lighting engineering, national development and improvement commission LED road lighting bidding projects and ten-city ten-thousand LED street lamps, the LED street lamps and other road lighting lamps have been gradually popularized and applied to urban road lighting, particularly urban main roads (8 lanes) by virtue of the advantages of high efficiency, energy conservation, high color rendering and the like; and are basically street lamps with mounting elevations.

With the development of urban construction and the increase of traffic flow, urban trunk roads are more widely repaired, especially in urban new areas, and some trunk roads are designed and constructed according to the superwidth of twelve lanes (42 meters wide); meanwhile, more and more cities begin to design street lamps and install elevation-free spherical lamps by utilizing the shape of the lamps and combining the cultural positioning attribute of the cities. However, the existing spherical lamp basically lacks of specific light distribution research, and is used for lighting conditions (hereinafter referred to as "wide-path conditions") required by urban ultra-wide main roads: twelve lanes, the installation space of the lighting lamps is moderate (the ratio of the space between the two lamps to the height of the lamps is more than 2.5 and less than 3), the light distribution requirement of double-side installation is not enough, so that the lighting effect cannot meet the requirement, and the index required by 'urban road lighting design Standard' CJJ45-2015 cannot be reached. In order to improve the lighting effect of the existing spherical lamp without an elevation angle under the working condition of a wide road, the applicant makes relevant research.

SUMMERY OF THE UTILITY MODEL

A first object of the utility model is to provide a be applied to lens unit of wide way operating mode.

A second object of the present invention is to provide a lens assembly for wide-road applications.

The third purpose of the utility model is to provide a be applied to street lamp holder of wide way operating mode.

In order to achieve the first object of the present invention, the present invention provides a lens unit applied to a wide-path working condition, the lens unit has an inner cavity for accommodating a light emitting device, the lens unit includes an incident surface located on an inner surface of the lens unit and an emergent surface located on an outer surface of the lens unit, the incident surface is an inward concave free-form surface, and the emergent surface is an outward convex free-form surface;

when the light-emitting device is arranged on the lens unit, the projection of the center of the light-emitting device on the bottom plane of the lens unit is positioned on the short axis of the lens unit, and the distance L between the projection of the center of the light-emitting device on the bottom plane of the lens unit and the geometric center of the bottom plane of the lens unit meets the requirement that L is more than 0 mm and less than or equal to 2 mm;

the light beam emitted from the light emitting device is incident on the incident surface at an incident angle ranging from-60 ° to 60 °, is refracted at a refraction angle ranging from-64.635 ° to 68.325 °, and is emitted from the exit surface at an exit angle ranging from-83.24 ° to 84.23 °.

According to the scheme, the center of the light-emitting device is arranged at a specific position (the distance L between the projection of the center of the light-emitting device on the bottom plane of the lens unit and the geometric center of the bottom plane of the lens unit is more than 0 mm and less than or equal to 2 mm), so that the center of the light-emitting device deviates from the geometric center of the bottom plane of the lens unit; and the light beam with the incident angle within the range of +/-60 degrees is incident to the lens unit, and is output to the outside after two refractions of the incident surface and the emergent surface, namely the incident light is correspondingly refracted by the angle with the value range of-64.635 degrees to 68.325 degrees and finally emitted from the emergent surface by the emergent angle of-83.24 degrees to 84.23 degrees, so that the light is effectively projected to the road surface after light distribution, a rectangular light spot is formed, the light distribution angle is accurate, the stray light is extremely small, the light utilization rate is high, the illumination requirement of wide road working conditions is met, and the illumination efficiency is effectively improved through a reasonable light distribution angle.

As a practical scheme, the distance L between the projection of the center of the light-emitting device on the bottom plane of the lens unit and the geometric center of the bottom plane of the lens unit satisfies 0.2 mm < L < 2 mm.

As a practical scheme, the distance L between the projection of the center of the light-emitting device on the bottom plane of the lens unit and the geometric center of the bottom plane of the lens unit satisfies 0.2 mm L1.5 mm.

As a practical scheme, the distance L between the projection of the center of the light-emitting device on the bottom plane of the lens unit and the geometric center of the bottom plane of the lens unit satisfies 1.5 mm < L ≦ 2 mm.

As an implementation scheme, the light beam emitted from the light emitting device is incident on the incident surface at an incident angle ranging from-60 ° to 60 °, then refracted at a refraction angle ranging from-52.362 ° to 59.536 °, and then emitted from the exit surface at an exit angle ranging from-63.23 ° to 66.65 °.

As an achievable solution, when L is 0.2 mm, the contour lines of the free-form surface of the incident surface and the free-form surface of the exit surface in the corresponding planes meet the following light distribution conditions;

in the first plane, the light beam emitted from the light-emitting device enters the incident plane at an incident angle ranging from-60 degrees to 60 degrees, is refracted at a refraction angle ranging from-56.183 degrees to 60.651 degrees correspondingly, and then exits from the exit plane at an exit angle ranging from-63.23 degrees to 66.65 degrees correspondingly;

in the second plane, the light beam emitted from the light emitting device enters the incident plane at an incident angle ranging from-60 degrees to 60 degrees, is refracted at a refraction angle ranging from-59.536 degrees to 59.536 degrees correspondingly, and then exits from the exit plane at an exit angle ranging from-76.63 degrees to 76.63 degrees correspondingly;

in the third plane, the light beam emitted from the light emitting device enters the incident plane at an incident angle ranging from-60 degrees to 60 degrees, is refracted at a refraction angle ranging from-55.536 degrees to 65.235 degrees correspondingly, and then exits from the exit plane at an exit angle ranging from-68.65 degrees to 81.25 degrees correspondingly;

in the fourth plane, the light beam emitted from the light emitting device enters the incident plane at an incident angle ranging from-60 degrees to 60 degrees, is refracted at a refraction angle ranging from-55.331 degrees to 64.325 degrees correspondingly, and then exits from the exit plane at an exit angle ranging from-67.75 degrees to 80.335 degrees correspondingly;

in a fifth plane, the light beam emitted from the light emitting device enters the incident plane at an incident angle ranging from-60 degrees to 60 degrees, is refracted at a refraction angle ranging from-50.237 degrees to 58.365 degrees correspondingly, and then exits from the exit plane at an exit angle ranging from-60.56 degrees to 73.254 degrees correspondingly;

the contour line in the sixth plane and the contour line in the fifth plane are symmetrically arranged relative to the first plane; the contour lines in the seventh plane and the contour lines in the fourth plane are symmetrically arranged relative to the first plane; the contour lines in the eighth plane and the contour lines in the third plane are arranged symmetrically with respect to the first plane.

As an achievable solution, when L is 1.5 mm, the contour lines of the free-form surface of the incident surface and the free-form surface of the exit surface in the corresponding planes meet the following light distribution conditions;

in a first plane, a light beam emitted from the light emitting device enters an incident plane at an incident angle ranging from-60 degrees to 60 degrees, is refracted at a refraction angle ranging from-54.766 degrees to 65.239 degrees correspondingly, and then exits from an exit plane at an exit angle ranging from-64.21 degrees to 68.5 degrees correspondingly;

in the second plane, the light beam emitted from the light emitting device enters the incident plane at an incident angle ranging from-60 degrees to 60 degrees, is refracted at a refraction angle ranging from-61.309 degrees to 61.309 degrees correspondingly, and then exits from the exit plane at an exit angle ranging from-77.8 degrees to 77.8 degrees correspondingly;

in the fourth plane, the light beam emitted from the light emitting device enters the incident plane at an incident angle ranging from-60 degrees to 60 degrees, is refracted at a refraction angle ranging from-54.235 degrees to 63.253 degrees correspondingly, and then exits from the exit plane at an exit angle ranging from-65.56 degrees to 79.58 degrees correspondingly;

in a fifth plane, the light beam emitted from the light emitting device enters the incident plane at an incident angle ranging from-60 degrees to 60 degrees, is refracted at a refraction angle ranging from-52.362 degrees to 61.235 degrees correspondingly, and then exits from the exit plane at an exit angle ranging from-63.25 degrees to 77.56 degrees correspondingly;

As an achievable solution, when L is 2 mm, the contour lines of the free-form surface of the incident surface and the free-form surface of the exit surface in the corresponding planes meet the following light distribution conditions;

in a first plane, a light beam emitted from the light emitting device enters an incident plane at an incident angle ranging from-60 degrees to 60 degrees, is refracted at a refraction angle ranging from-56.523 degrees to 66.354 degrees correspondingly, and then exits from an exit plane at an exit angle ranging from-66.53 degrees to 70.56 degrees correspondingly;

in the second plane, the light beam emitted from the light emitting device enters the incident plane at an incident angle ranging from-60 degrees to 60 degrees, is refracted at a refraction angle ranging from-64.635 degrees to 64.635 degrees correspondingly, and then exits from the exit plane at an exit angle ranging from-83.24 degrees to 83.24 degrees correspondingly;

in the third plane, the light beam emitted from the light emitting device enters the incident plane at an incident angle ranging from-60 degrees to 60 degrees, is refracted at a refraction angle ranging from-60.237 degrees to 68.325 degrees correspondingly, and then exits from the exit plane at an exit angle ranging from-71.32 degrees to 84.23 degrees correspondingly;

in the fourth plane, the light beam emitted from the light emitting device enters the incident plane at an incident angle ranging from-60 degrees to 60 degrees, is refracted at a refraction angle ranging from-56.354 degrees to 64.358 degrees correspondingly, and then exits from the exit plane at an exit angle ranging from-67.85 degrees to 82.65 degrees correspondingly;

in the fifth plane, the light beam emitted from the light emitting device enters the incident plane at an incident angle ranging from-60 degrees to 60 degrees, is refracted at a refraction angle ranging from-54.571 degrees to 63.254 degrees correspondingly, and then exits from the exit plane at an exit angle ranging from-66.36 degrees to 79.85 degrees correspondingly;

In a further aspect, the lens unit is provided with two positioning and mounting posts protruding from a bottom plane of the lens unit.

Through the symmetrical two location erection columns that set up on the lens unit, can be swift, accurate will the lens unit is installed on the base plate, improves production efficiency.

In a further aspect, the two positioning and mounting posts are symmetrically arranged at two ends of the long axis of the lens unit or on the extension line of the long axis.

Through the two positioning mounting columns symmetrically arranged at the two ends of the long axis of the lens unit or on the extension line of the long axis, the lens unit can be better fixed, and the shielding influence of the positioning mounting columns on light rays is reduced as much as possible.

The further proposal is that a convex rib is arranged on the periphery of the positioning mounting column; an included angle is formed between the center line of the convex rib arranged on the two positioning mounting columns and the plane formed by the axes of the corresponding positioning mounting columns.

The two convex ribs with different directions are arranged on the peripheries of the two positioning mounting columns, so that a pair of contradictions that the lens unit is installed on the base plate and is too loose and too tight to be inserted into the hole can be solved.

It can be seen from above that the installation of the light emitting device is more convenient and firm through the installation groove and the positioning groove of the lens unit.

In order to achieve the second object of the present invention, the present invention provides a lens assembly applied to a wide-road working condition, the lens assembly includes a plurality of lens units, and the lens units are the aforementioned lens units; and the plurality of lens units are arranged on the lens component in a consistent installation form.

By above-mentioned scheme, through set up the lens unit that the installation form is unanimous on the lens subassembly, guarantee that lens unit emergent ray direction is unanimous, and then make the lens subassembly can improve the light efficiency greatly, make more light can project on the road then.

Still further, the lens assembly further comprises a substrate, and the plurality of lens units are arranged on the substrate and are uniformly distributed along the circumference.

As can be seen from the above, the irradiation range can be enlarged by the circumferentially arranged lens units.

In a further aspect, the lens assembly further includes a substrate, and the plurality of lens units are disposed on the substrate and sequentially arranged along a same direction.

Therefore, through the lens units distributed along the same direction, the illumination range and the illumination uniformity of the lens assembly can be further improved while the light effect is provided.

In order to realize the utility model discloses a third purpose, the utility model provides a be applied to street lamp holder of wide way operating mode, including top cap, lamp shade, lamp stand and lens unit, the lens unit is aforementioned lens unit.

According to the scheme, as mentioned above, the street lamp cap has the characteristics of accurate light distribution angle of the lens unit, extremely small stray light, high light utilization rate, energy conservation and the like, so that when the street lamp cap is applied to a wide road working condition, the street lamp cap can effectively improve the illumination efficiency and meet corresponding requirements.

The street lamp is characterized in that the street lamp comprises a plurality of street lamp caps, and the street lamp caps are arranged on the street lamp caps in a same manner.

A further scheme is that when the street lamp cap is applied to an actual scene, the short axis direction of the lens unit is arranged along the width direction of the road, the positive direction of the short axis of the lens unit faces the middle of the road, and the long axis direction of the lens unit is arranged along the length direction of the road.

From top to bottom, through set up the lens unit that the installation form is unanimous on the street lamp holder, guarantee that lens unit emergent ray direction is unanimous, and then can improve the light efficiency of street lamp holder greatly, make more light can project on the road then.

Drawings

Fig. 1 is a view of a lens unit according to an embodiment of the present invention at a first viewing angle.

Fig. 2 is a structural diagram of an embodiment of the lens unit of the present invention at a second viewing angle.

Fig. 3A is a structural diagram of an embodiment of a lens unit according to the present invention at a third viewing angle.

Fig. 3B is a diagram of a lens unit according to an embodiment of the present invention at a fourth viewing angle.

Fig. 3C is a structural diagram of the lens unit according to the embodiment of the present invention after the light emitting device is mounted.

Fig. 4 is a plan view of an embodiment of the lens unit of the present invention after a light emitting device is mounted thereon.

Fig. 5 is a cross-sectional view at a-a in fig. 4.

Fig. 6 is a schematic diagram of the optical path at a-a in fig. 4.

Fig. 7 is a sectional view at B-B in fig. 4.

Fig. 8 is a schematic diagram of the optical path at B-B in fig. 4.

Fig. 9 is a cross-sectional view at C-C in fig. 4.

Fig. 10 is a cross-sectional view taken at D-D in fig. 4.

Fig. 11 is a cross-sectional view at E-E in fig. 4.

Figure 12 is a block diagram of a first embodiment of the lens assembly of the present invention.

Figure 13 is a block diagram of a second embodiment of the lens assembly of the present invention.

Fig. 14 is a structural diagram of the street lamp cap according to the embodiment of the present invention.

Fig. 15 is an exploded view of the street light head according to the embodiment of the present invention.

Fig. 16 is a block diagram of a top cover and lens assembly in an embodiment of a street light head of the present invention.

Fig. 17 is the utility model discloses the pseudo-color expression under the wide road operating mode is applied to the street lamp holder.

Fig. 18 is the utility model discloses street lamp holder is applied to the constant illuminance map under the wide road operating mode.

Fig. 19 is the utility model discloses the point illuminance map under the wide way operating mode is applied to the street lamp holder.

The present invention will be further explained with reference to the drawings and examples.

Detailed Description

Lens unit embodiment:

referring to fig. 1, 2 and 3A, 3B, 3C, fig. 1, 2 and 3A, 3B, 3C are structural views of a lens unit applied to a wide road condition at different viewing angles. The lens unit 1 is a light distribution lens made of transparent materials and provided with an inner cavity, and the inner cavity is in a dome shape and used for mounting light emitting devices such as LED light emitting chips and light emitting devices comprising the LED light emitting chips; the lens unit 1 comprises an incident surface 12 positioned on the inner surface (the inner cavity surface) of the lens unit and an emergent surface 11 positioned on the outer surface of the lens unit, the emergent surface 11 is a convex continuous free-form surface, the emergent surface 11 comprises a first emergent surface 111 and a second emergent surface 112, and the first emergent surface 111 and the second emergent surface 112 are arranged in mirror symmetry along a horizontal X direction (the X direction in the embodiment corresponds to the road length direction when the lens unit is applied to a spherical lamp and is also the long axis direction of the lens unit); the projections formed by the free-form surfaces of the first emission surface 111 and the second emission surface 112 are disposed obliquely toward the first side (the Y-direction forward direction, the direction indicated by the arrow) in the Y direction (perpendicular to the X direction, which is also the short-axis direction of the lens unit). X, Y, Z intersect the geometric center of the lens cell base plane (the intersection of the lens cell minor axis and the lens cell major axis) and are perpendicular to each other.

The incident surface 12 is a concave continuous free-form surface, the incident surface 12 includes a first incident surface 121 and a second incident surface 122, the first incident surface 121 and the second incident surface 122 are arranged in mirror symmetry along the horizontal X direction, and the free-form surfaces of the first incident surface 121 and the second incident surface 122 are arranged along the formed protrusion obliquely toward the second side (negative direction of the Y direction) of the Y direction. A light emitting device mounting groove 13 is formed in the bottom of the lens unit 1 (at an opening of the inner cavity), the light emitting device mounting groove 13 is formed in a square groove shape (or a circular groove shape), and a step 131 is formed in one side of the light emitting device mounting groove 13 facing the inner cavity. Two positioning and mounting posts 19 protruding from the bottom plane of the lens unit 1 are symmetrically arranged at two ends of the long axis of the lens unit 1 (or on the extension line of the long axis or other positions). By symmetrically arranging the two positioning mounting columns 19 (as shown in fig. 3B) in the long axis direction of the lens unit, the lens unit can be quickly and accurately mounted on the substrate, and the production efficiency is improved. In addition, a convex rib 191 is arranged on the periphery of the positioning mounting column 19; an included angle (90 degrees in the embodiment) exists between the center line of the rib 191 arranged on the two positioning and mounting columns 19 and the plane formed by the axes of the corresponding positioning and mounting columns 19. The two convex ribs with different directions are arranged on the peripheries of the two positioning mounting columns, so that a pair of contradictions that the lens unit is installed on the base plate and is too loose and too tight to be inserted into the hole can be solved.

Referring to fig. 4, 5 and 6, fig. 5 is a sectional view at a-a in fig. 4, i.e., a sectional view at a midline a-a (over the short axis) in the horizontal Y direction (90 ° -270 ° direction) of the lens unit 1, and fig. 6 is a principle view of an optical path at a-a in fig. 5. A light emitting device 14 is mounted on the light emitting device mounting groove 13.

The light emitting device 14 is installed with an LED light emitting chip (as a possible implementation manner, the LED light emitting chip may also be directly adopted), and the LED light emitting chip outputs a light beam towards the incident surface 12, and the light beam passes through the lens unit according to an optical principle and then is emitted from the exit surface 11. When the light emitting device 14 is installed on the lens unit 1, the projection of the center of the light emitting device (the center of the LED light emitting chip) on the bottom plane 10 of the lens unit is located on the short axis of the lens unit, and the distance L between the projection of the center of the light emitting device on the bottom plane of the lens unit and the geometric center of the bottom plane of the lens unit (the intersection point of the short axis of the lens unit and the long axis of the lens unit) along the short axis direction of the lens unit satisfies 0 mm < L < 2 mm, preferably 0.2 mm < L < 2 mm.

Assuming that a light beam emitted in a direction perpendicular to the center of the LED light emitting chip is taken as a central light beam (defined as an optical axis S), a straight line parallel to the optical axis S is made at an incident point of the light beam emitted from the LED light emitting chip on the incident surface 12, and an included angle between the straight line and the light beam emitted from the LED light emitting chip is taken as an incident angle (corresponding to an included angle between the optical axis S and the light beam emitted from the LED light emitting chip being taken as an incident angle), similarly, the refraction angle and the emission angle of the present embodiment can be expressed as an included angle between the corresponding light beam and the straight line (or the optical axis S) parallel to the optical axis S.

When L ═ 1.5 mm:

in the present embodiment, the light beam emitted from the LED light emitting chip enters the incident plane 12 at a first incident angle a (which is a range of ± 60 ° and the light beam forms a cone shape) in a plane (referred to as a plane passing through the short axis of the lens unit, or a first plane) passing through the short axis of the lens unit and perpendicular to the bottom plane of the lens unit, and then is refracted at a first refraction angle b ranging from-54.766 ° (which corresponds to an incident angle of-60 °) to 65.239 °, and then exits from the exit plane 11 at a first exit angle c ranging from-64.21 ° to 68.5 ° in the first plane. In a more specific implementation manner, the cross-sectional contour lines (in the first plane) of the free-form surface of the incident surface 12 and the free-form surface of the emitting surface 11 at a-a conform to the following incident light and emitted light distribution conditions:

according to the light distribution conditions in the above table, the coordinate values of each point of the structural contour line (in the first plane) of the a-a section of the exit plane 11 and the entrance plane 12 in the Y direction can be calculated by the numerical calculation method through the integral iteration method, and then all characteristic contour curve (in the first plane) parameters of the a-a section of the exit plane 11 and the entrance plane 12 can be generated by using computer aided design software such as ZEMAX, lighttools, and the like.

Referring to fig. 4, 7 and 8, fig. 7 is a cross-sectional view at B-B in fig. 4, i.e., a cross-sectional view of the lens unit 1 at B-B (passing through the center of the LED chip and parallel to the long axis of the lens unit) in the horizontal X direction (0-180 direction), and fig. 8 is a schematic diagram of the optical path at B-B in fig. 4; the X direction is perpendicular to the Y direction.

The LED light emitting chip outputs a light beam toward the incident surface 12, and the light beam passes through the lens unit according to the optical principle and then exits from the exit surface 11. In the present embodiment, the light beam emitted from the LED light emitting chip enters the incident surface 12 at the second incident angle d (within a range of ± 60 °) in a plane (referred to as a plane passing through the center of the LED chip and parallel to the straight line of the long axis of the lens unit, or a second plane) perpendicular to the bottom plane of the lens unit, and then is refracted at the second refraction angle e (corresponding to a range of ± 61.309 °), and then exits from the exit surface 11 at the second exit angle f within a range of ± 77.8 ° in the second plane.

The free-form surface of the incident surface 12 is arranged symmetrically with respect to the first plane in a cross-sectional contour line (in the second plane) at B-B, and the free-form surface of the exit surface 11 is arranged symmetrically with respect to the first plane in a cross-sectional contour line in the second plane. As a more specific implementation manner, the section contour lines (in the second plane) of the free-form surface of the incident surface 11 and the free-form surface of the emergent surface 12 at B-B conform to the incident light and emergent light distribution conditions:

according to the light distribution conditions in the above table, the coordinate values of the points of the structure contour line of the B-B section of the exit plane 11 and the incident plane 12 can be calculated by numerical calculation through an integral iteration method, and then all characteristic contour curve (in the second plane) parameters of the exit plane 11 and the incident plane 12 in the B-B section can be generated by computer aided design software such as ZEMAX, lighttools and the like.

Referring to fig. 4 and 9, fig. 9 is a cross-sectional view at C-C in fig. 4, i.e., a cross-sectional view of the lens unit 1 at C-C (passing through the center of the LED chip and making an angle of 30 with the long axis of the lens unit (i.e., in the direction of 30-210 °) in a direction of 30 ° with respect to the X-direction.

The LED light emitting chip outputs a light beam toward the incident surface 12, and the light beam passes through the lens unit according to the optical principle and then exits from the exit surface 11. In this embodiment, the light beam emitted from the LED light emitting chip enters the incident plane 12 at a third incident angle (within a range of ± 60 °) in a plane (referred to as a plane passing through the center of the light emitting device and a straight line forming an angle of 30 ° with the long axis of the lens unit, or a third plane) perpendicular to the bottom plane of the lens unit, passing through the center of the LED chip and forming an angle of 30 ° with the long axis of the lens unit, is refracted at a third refraction angle ranging from-55.536 ° (corresponding to an incident angle of-60 °) to 65.235 °, and exits from the exit plane 11 at a third exit angle ranging from-68.65 ° to 81.25 °.

As a more specific implementation manner, the cross-sectional contour lines (in the third plane) of the free-form surface of the incident surface 11 and the free-form surface of the emission surface 12 at C-C conform to the incident light and emission light distribution conditions:

according to the light distribution conditions in the above table, the coordinate values of the points of the structure contour line of the C-C cross section of the exit plane 11 and the entrance plane 12 can be calculated by numerical calculation through an integral iteration method, and then all characteristic contour curve (in the third plane) parameters of the C-C cross section of the exit plane 11 and the entrance plane 12 can be generated by computer aided design software such as ZEMAX, lighttools and the like. All characteristic profile curve parameters of the lens unit 1 in a plane (for short, eighth plane) passing through the center of the light emitting device and forming an included angle of 150 degrees (namely, 150-330 degrees) with the long axis (X direction) of the lens unit and perpendicular to the bottom plane of the lens unit are symmetrical to all characteristic profile curve parameters in a plane (third plane) passing through the center of the light emitting device and forming an included angle of 30 degrees with the long axis of the lens unit (the first plane is taken as a symmetrical plane).

Referring to fig. 4 and 10, fig. 10 is a cross-sectional view at D-D in fig. 4, i.e., a cross-sectional view of the lens unit 1 at D-D (passing through the center of the LED chip and making an angle of 45 with the long axis of the lens unit (i.e., 45-225) in a direction making an angle of 45 with the X-direction.

The LED light emitting chip outputs a light beam toward the incident surface 12, and the light beam passes through the lens unit according to the optical principle and then exits from the exit surface 11. In this embodiment, the light beam emitted from the LED light emitting chip enters the incident surface 12 at a fourth incident angle (within a range of ± 60 °) in a plane (referred to as a plane passing through the center of the light emitting device and forming an angle of 45 ° with the long axis of the lens unit, or a fourth plane) perpendicular to the bottom plane of the lens unit and passing through the center of the LED chip and forming an angle of 45 ° with the long axis of the lens unit, is refracted at a fourth refraction angle ranging from-54.235 ° (corresponding to an incident angle of-60 °) to 63.253 °, and exits from the exit surface 11 at a fourth exit angle ranging from-65.56 ° to 79.58 °.

As a more specific implementation manner, the cross-sectional contour lines of the free-form surface of the incident surface 11 and the free-form surface of the emergent surface 12 at D-D (in the fourth plane) conform to the incident light and emergent light distribution conditions:

according to the light distribution conditions in the above table, the coordinate values of the exit surface 11 and the entrance surface 12 at each point of the structure contour line of the D-D profile can be calculated by numerical calculation using an integral iteration method, and then all characteristic contour curve (in the fourth plane) parameters of the exit surface 11 and the entrance surface 12 at the D-D profile can be generated by using computer aided design software such as ZEMAX, lighttools, and the like. All characteristic profile curve parameters of the lens unit 1 in a plane (a seventh plane for short) passing through the center of the light emitting device and forming an included angle of 135 degrees (namely 135-315 degrees) with the long axis (X direction) of the lens unit and perpendicular to the bottom plane of the lens unit are symmetrical to all characteristic profile curve parameters in a plane (a fourth plane) passing through the center of the light emitting device and forming an included angle of 45 degrees with the long axis of the lens unit (the first plane is taken as a symmetrical plane).

Referring to fig. 4 and 11, fig. 11 is a cross-sectional view at E-E in fig. 4, i.e., a cross-sectional view of the lens unit 1 at E-E (passing through the center of the LED chip and making an angle of 60 with the long axis of the lens unit (i.e., 60-240 direction)) in a direction of 60 with respect to the X-direction.

The LED light emitting chip outputs a light beam toward the incident surface 12, and the light beam passes through the lens unit according to the optical principle and then exits from the exit surface 11. In this embodiment, the light beam emitted from the LED light emitting chip is incident on the incident surface 12 at a fifth incident angle (within ± 60 °) in a plane passing through the center of the LED chip and forming an angle of 60 ° with the long axis of the lens unit and perpendicular to the bottom plane of the lens unit (herein, simply referred to as a plane passing through the center of the light emitting device and forming an angle of 60 ° with the long axis of the lens unit, or a fifth plane), is refracted at a fifth refraction angle ranging from-52.362 ° (corresponding to an incident angle of-60 °) to 61.235 °, and is emitted from the emitting surface 11 at a fifth exit angle ranging from-63.25 ° to 77.56 ° in the fifth plane.

As a more specific implementation manner, the cross-sectional contour lines (in the fifth plane) of the free-form surface of the incident surface 11 and the free-form surface of the emergent surface 12 at positions E-E conform to the incident light and emergent light distribution conditions:

according to the light distribution conditions in the above table, the coordinate values of the points of the structure contour line of the D-D section of the exit surface 11 and the incident surface 12 can be calculated by numerical calculation through an integral iteration method, and then all characteristic contour curve (in the fifth plane) parameters of the exit surface 11 and the incident surface 12 in the E-E section can be generated by using computer aided design software such as ZEMAX, lighttools, and the like. All characteristic profile curve parameters of the lens unit 1 in a plane (a sixth plane for short) passing through the center of the light emitting device and forming an included angle of 120 degrees (namely, 120-300 degrees) with the long axis (X direction) of the lens unit and perpendicular to the bottom plane of the lens unit are symmetrical to all characteristic profile curve parameters in a plane (a fifth plane) passing through the center of the light emitting device and forming an included angle of 60 degrees with the long axis of the lens unit (the first plane is taken as a symmetrical plane).

When L is 2 mm:

as shown in fig. 4, in the present embodiment, the light beam emitted from the LED light emitting chip enters the incident plane 12 at a first incident angle (in a range of ± 60 °) in a plane passing through the short axis of the lens unit and perpendicular to the bottom plane of the lens unit (in this application, referred to as a plane passing through the short axis of the lens unit, or a first plane), is refracted at a first refraction angle in a range of-56.523 ° (corresponding to an incident angle of-60 °) to 66.354 °, and exits from the exit plane 11 at a first exit angle in the range of-66.53 ° to 70.56 °. In a more specific implementation manner, the cross-sectional contour lines (in the first plane) of the free-form surface of the incident surface 12 and the free-form surface of the emitting surface 11 at a-a conform to the following incident light and emitted light distribution conditions:

according to the light distribution conditions in the above table, the coordinate values of each point of the structural contour line (in the first plane) of the a-a section of the exit plane 11 and the entrance plane 12 in the Y direction can be calculated by the numerical calculation method through the integral iteration method, and then all characteristic contour curve (in the first plane) parameters of the a-a section of the exit plane 11 and the entrance plane 12 can be generated by using computer aided design software such as ZEMAX, lighttools, and the like. Since L2 mm and L1.5 do not differ much from the respective schematic diagrams, the approximate form of the section a-A, B-B, C-C, D-D, E-E in the implementation of L2 mm can be seen in fig. 5 to 11.

In the present embodiment, the light beam emitted from the LED light emitting chip is incident on the incident surface 12 at a second incident angle (within a range of ± 60 °) in a plane passing through a straight line passing through the center of the LED chip and parallel to the long axis of the lens unit and perpendicular to the bottom plane of the lens unit (in this application, simply referred to as a plane passing through the center of the light emitting device and parallel to the long axis of the lens unit, or in a second plane), and is then refracted at a second refraction angle (corresponding to a range of ± 64.635 °), and then exits from the exit surface 11 at a second exit angle corresponding to a range of ± 83.24 °.

The free-form surface of the incident surface 12 has a sectional contour (in the second plane) at B-B arranged symmetrically with respect to the first plane, and the free-form surface of the exit surface 11 has a sectional contour in a plane passing through the center of the light emitting device and parallel to the long axis of the lens unit arranged symmetrically with respect to the first plane. As a more specific implementation manner, the section contour lines (in the second plane) of the free-form surface of the incident surface 11 and the free-form surface of the emergent surface 12 at B-B conform to the incident light and emergent light distribution conditions:

In this embodiment, the light beam emitted from the LED light emitting chip is incident on the incident plane 12 at a third incident angle (within ± 60 °) in a plane passing through a straight line passing through the center of the LED chip and forming an angle of 30 ° with the long axis of the lens unit and perpendicular to the bottom plane of the lens unit (herein, simply referred to as a plane passing through the center of the light emitting device and forming an angle of 30 ° with the long axis of the lens unit, or a third plane), is refracted at a third refraction angle corresponding to a range of-60.237 ° (corresponding to an incident angle of-60 °) to 68.325 °, and is emitted from the exit plane 11 at a third exit angle corresponding to a range of-71.32 ° to 84.23 °.

according to the light distribution conditions in the above table, the coordinate values of the points of the structure contour line of the C-C cross section of the exit plane 11 and the entrance plane 12 can be calculated by numerical calculation through an integral iteration method, and then all characteristic contour curve (in the third plane) parameters of the C-C cross section of the exit plane 11 and the entrance plane 12 can be generated by computer aided design software such as ZEMAX, lighttools and the like. All characteristic profile curve parameters of the lens unit 1 in a plane (for short, eighth plane) passing through the center of the light emitting device and forming an included angle of 150 degrees (namely 150-330 degrees) with the long axis (X direction) of the lens unit and perpendicular to the bottom plane of the lens unit are symmetrical to all characteristic profile curve parameters in a plane (in third plane) passing through the center of the light emitting device and forming an included angle of 30 degrees with the long axis of the lens unit (the first plane is taken as a symmetrical plane).

In this embodiment, the light beam emitted from the LED light emitting chip is incident on the incident surface 12 at a fourth incident angle (within a range of ± 60 °) in a plane passing through a straight line passing through the center of the LED chip and forming an angle of 45 ° with the long axis of the lens unit and perpendicular to the bottom plane of the lens unit (herein, simply referred to as a plane passing through the center of the light emitting device and forming an angle of 45 ° with the long axis of the lens unit, or a fourth plane), is refracted at a fourth refraction angle corresponding to a range of-56.354 ° (corresponding to an incident angle of-60 °) to 64.358 °, and is emitted from the emitting surface 11 at a fourth exit angle corresponding to a range of-67.85 ° to 82.65 °.

As a more specific implementation manner, the cross-sectional outlines (in the fourth plane) of the free-form surface of the incident surface 11 and the free-form surface of the emergent surface 12 at D-D conform to the incident light and emergent light distribution conditions:

according to the light distribution conditions in the above table, the coordinate values of the exit surface 11 and the entrance surface 12 at each point of the structure contour line of the D-D profile can be calculated by numerical calculation using an integral iteration method, and then all characteristic contour curve (in the fourth plane) parameters of the exit surface 11 and the entrance surface 12 at the D-D profile can be generated by using computer aided design software such as ZEMAX, lighttools, and the like. All characteristic profile curve parameters of the lens unit 1 in a plane (for short, a seventh plane) passing through the center of the light emitting device and forming an included angle of 135 degrees (namely 135-315 degrees) with the long axis (X direction) of the lens unit and perpendicular to the bottom plane of the lens unit are symmetrical to all characteristic profile curve parameters in a plane (in a fourth plane) passing through the center of the light emitting device and forming an included angle of 45 degrees with the long axis of the lens unit (the first plane is taken as a symmetrical plane).

In this embodiment, the light beam emitted from the LED light emitting chip is incident on the incident surface 12 at a fifth incident angle (within ± 60 °) in a plane passing through the center of the LED chip and forming an angle of 60 ° with the long axis of the lens unit and perpendicular to the bottom plane of the lens unit (in this application, simply referred to as a plane passing through the center of the light emitting device and forming an angle of 60 ° with the long axis of the lens unit, or a fifth plane), is refracted at a fifth refraction angle ranging from-54.571 ° (corresponding to an incident angle of-60 °) to 63.254 °, and is emitted from the emitting surface 11 at a fifth emission angle ranging from-66.36 ° to 79.85 ° in the fifth plane.

When L is 0.2 mm:

as shown in fig. 4, in the present embodiment, the light beam emitted from the LED light emitting chip enters the incident plane 12 at a first incident angle (within ± 60 °) in a plane passing through the short axis of the lens unit and perpendicular to the bottom plane of the lens unit (or in a first plane, for short, in the plane passing through the short axis of the lens unit), is refracted at a first refraction angle ranging from-56.183 ° (corresponding to an incident angle of-60 °) to 60.651 °, and exits from the exit plane 11 at a first exit angle ranging from-63.23 ° to 66.65 ° in the first plane. In a more specific implementation manner, the cross-sectional contour lines (in the first plane) of the free-form surface of the incident surface 12 and the free-form surface of the emitting surface 11 at a-a conform to the following incident light and emitted light distribution conditions:

according to the light distribution conditions in the above table, the coordinate values of each point of the structural contour line (in the first plane) of the a-a section of the exit plane 11 and the entrance plane 12 in the Y direction can be calculated by the numerical calculation method through the integral iteration method, and then all characteristic contour curve (in the first plane) parameters of the a-a section of the exit plane 11 and the entrance plane 12 can be generated by using computer aided design software such as ZEMAX, lighttools, and the like. Since L-0.2 mm and L-1.5 do not differ much from the respective schematic diagrams, the approximate form of the section a-A, B-B, C-C, D-D, E-E in the implementation of L-0.2 mm can be referred to fig. 5 to 11.

In the present embodiment, the light beam emitted from the LED light emitting chip is incident on the incident surface 12 at a second incident angle (within a range of ± 60 °) in a plane passing through a straight line passing through the center of the LED chip and parallel to the long axis of the lens unit and perpendicular to the bottom plane of the lens unit (in this application, simply referred to as a plane passing through the center of the light emitting device and parallel to the long axis of the lens unit, or in a second plane), and is then refracted at a second refraction angle (corresponding to a range of ± 59.536 °), and then exits from the exit surface 11 at a second exit angle corresponding to a range of ± 76.63 °.

In this embodiment, the light beam emitted from the LED light emitting chip is incident on the incident plane 12 at a third incident angle (within ± 60 °) in a plane passing through a straight line passing through the center of the LED chip and forming an angle of 30 ° with the long axis of the lens unit and perpendicular to the bottom plane of the lens unit (herein, simply referred to as a plane passing through the center of the light emitting device and forming an angle of 30 ° with the long axis of the lens unit, or a third plane), is refracted at a third refraction angle corresponding to a range of-55.536 ° (corresponding to an incident angle of-60 °) to 65.235 °, and is emitted from the emission plane 11 at a third emission angle corresponding to a range of-68.65 ° to 81.25 °.

In this embodiment, the light beam emitted from the LED light emitting chip is incident on the incident surface 12 at a fourth incident angle (within a range of ± 60 °) in a plane passing through a straight line passing through the center of the LED chip and forming an angle of 45 ° with the long axis of the lens unit and perpendicular to the bottom plane of the lens unit (herein, simply referred to as a plane passing through the center of the light emitting device and forming an angle of 45 ° with the long axis of the lens unit, or a fourth plane), is refracted at a fourth refraction angle corresponding to a range of-55.331 ° (corresponding to an incident angle of-60 °) to 64.325 °, and is emitted from the emitting surface 11 at a fourth exit angle corresponding to a range of-67.75 ° to 80.335 °.

according to the light distribution conditions in the above table, the coordinate values of the exit surface 11 and the entrance surface 12 at each point of the structure contour line of the D-D profile can be calculated by numerical calculation using an integral iteration method, and then all characteristic contour curve (in the fourth plane) parameters of the exit surface 11 and the entrance surface 12 at the D-D profile can be generated by using computer aided design software such as ZEMAX, lighttools, and the like. All characteristic profile curve parameters of the lens unit 1 in a plane (for short, a seventh plane) passing through the center of the light emitting device and forming an included angle of 135 degrees (namely 135-315 degrees) with the long axis (X direction) of the lens unit and perpendicular to the bottom plane of the lens unit are symmetrical to all characteristic profile curve parameters in a plane (in a fourth plane) passing through the center of the light emitting device and forming an included angle of 30 degrees with the long axis of the lens unit (the first plane is taken as a symmetrical plane).

In this embodiment, the light beam emitted from the LED light emitting chip is incident on the incident surface 12 at a fifth incident angle (within ± 60 °) in a plane passing through the center of the LED chip and forming an angle of 60 ° with the long axis of the lens unit and perpendicular to the bottom plane of the lens unit (herein, simply referred to as a plane passing through the center of the light emitting device and forming an angle of 60 ° with the long axis of the lens unit, or a fifth plane), is refracted at a fifth refraction angle ranging from-52.362 ° (corresponding to an incident angle of-60 °) to 61.235 °, and is emitted from the emitting surface 11 at a fifth exit angle ranging from-63.25 ° to 77.56 ° in the fifth plane.

Lens assembly first embodiment:

referring to FIG. 12, FIG. 12 is a block diagram of a first embodiment of a lens assembly. The lens assembly comprises a substrate 15, a plurality of light emitting devices and a plurality of lens units 16 manufactured according to the above lens unit embodiments, the substrate 15 is annularly arranged, the substrate 15 is electrically connected with the plurality of light emitting devices, the plurality of light emitting devices are uniformly distributed along the circumferential direction, the lens units 16 are sleeved outside the light emitting devices, so that the lens units 16 are uniformly distributed along the circumferential direction, and the installation forms of the plurality of lens units 16 are consistent (namely, when the plurality of lens units are installed, the positive directions of the short axis are consistent, and the positive directions of the long axis are consistent), namely, the arrangement shown in fig. 12; the installation form is unanimous, can make the lens unit emergent ray direction unanimous, enlargies the stack effect, and then makes the lens subassembly can improve the light efficiency greatly. When the lens assembly is applied to a spherical lamp and the spherical lamp is applied to a wide-road condition, the minor axis direction of the lens unit 16 corresponds to the road width direction, and the major axis direction of the lens unit corresponds to the road length direction. The embodiment of the utility model provides a plurality of, the meaning is two or more.

Lens assembly second embodiment:

referring to FIG. 13, FIG. 13 is a block diagram of a second embodiment of a lens assembly. The lens assembly includes a substrate 17, light emitting devices, and a plurality of lens units 18 manufactured according to the above-mentioned embodiments of the lens units, the substrate 17 is disposed in a long strip shape, four light emitting devices are electrically connected to the substrate 17, the four light emitting devices are sequentially arranged and distributed along the same direction, the lens units 18 are sleeved outside the light emitting devices, so that the lens units 18 are sequentially arranged and distributed along the same direction, and the plurality of lens units 18 are installed in the same shape, so that the light emitting directions of the lens units are the same, that is, the arrangement shown in fig. 10. When the lens assembly is applied to a spherical lamp and the spherical lamp is applied to a wide-road condition, the minor axis direction of the lens unit 18 corresponds to the road width direction, and the major axis direction of the lens unit corresponds to the road length direction.

Street lamp holder embodiment:

referring to fig. 14, fig. 14 is a structural view of the street lamp. The street lamp includes lamp stand 2, lamp shade 3 and top cap 4, and the stiff end of lamp stand 2 is opened and is used for with lamp pole fixed connection, and lamp shade 3 is installed in the top of lamp stand 2, and lamp shade 3 adopts the printing opacity material preparation to form, and the top at lamp shade 3 is installed to top cap 4. The top cover 4 is arranged in a disc shape, a plurality of heat dissipation fins 41 are arranged on the outward end surface of the top cover 4, the plurality of heat dissipation fins 41 are arranged in a spiral shape with the center of the top cover 4 as the original point, and a heat conduction groove for air circulation is formed between every two adjacent heat dissipation fins 41.

Referring to fig. 15 and 16, fig. 15 is an exploded view of the street light in a sectional view, and fig. 16 is a structural view of a lens assembly and a top cover. The shape is spherical lamp shade 3 middle part formation and holds the chamber, holds the chamber and is provided with first opening 31 and second opening 32 respectively at both ends along the axial, installs reflection of light piece 5 at the intracavity that holds of lamp shade 3, and reflection of light piece 5 is the equal open toper setting of upper end and lower extreme. The outer surface of the reflector 5 is coated with a reflective material, the reflector 5 is provided with a hollow cavity along the axial direction, and the lower end of the reflector 5 is fixedly connected with the lamp holder 2.

The end face of the top cover 4 facing the lampshade 3 is provided with the lens assembly 42, the lens assembly 42 comprises a substrate 421, a light emitting device connected to the substrate and a lens unit 422 sleeved outside the light emitting device, the substrate 421 is connected with the end face of the top cover 4 facing the lampshade 3, the lens unit 422 is manufactured according to the embodiment of the lens unit, and the lens assembly emits light towards the lampshade 3. The plurality of lens units are uniformly distributed along the circumferential direction, and the installation forms of the plurality of lens units are consistent (namely, when the plurality of lens units are installed, the positive directions of the short axes are consistent, and the positive directions of the long axes are consistent), namely, the arrangement is shown in fig. 16; the installation forms of the lens units are consistent, the emergent light directions of the lens units are consistent, the superposition effect is amplified, and the lighting effect of the street lamp cap is greatly improved.

The lamp holder 2 is cup-shaped, a concave cavity is formed in the middle of the lamp holder 2, and the lamp holder 2 is provided with a reflecting part 5, a tension rod and a power supply assembly. The first end of the tension rod passes through the light reflecting part 5 and the top cover 4 to be matched with the nut (or directly matched with the top cover 4 by screw threads), and the second end of the tension rod 22 is fixedly connected in the light reflecting part.

The inner wall of street lamp shade 3 still is provided with many first grading ribs (not shown, as a possible implementation, also can not be provided with many first grading ribs at street lamp shade 3's inner wall, and first grading rib extends the setting along the warp direction, and many first grading ribs are along weft direction evenly distributed, and the cross section of first grading rib is the V type to be provided with the chamfer at the outermost tip of first grading rib, many first grading ribs extend to second opening 32 from first opening 31.

As can be seen from the above, since the street lamp cap comprises a plurality of lens units with specific light distribution conditions, the center of the light emitting device is arranged at a specific position (the distance L between the projection of the center of the light emitting device on the bottom plane of the lens unit and the geometric center of the bottom plane of the lens unit satisfies 0 mm < L < 2 mm), and deviates from the geometric center of the bottom plane of the lens unit; and the light beam with the incident angle within the range of +/-60 degrees is incident to the lens unit, and is output to the outside after being refracted twice by the incident surface and the emergent surface, namely the incident light beam is refracted by an angle with the value range of-64.635 degrees to 68.325 degrees and is finally emergent from the emergent surface at an emergent angle of-83.24 degrees to 84.23 degrees, so that the light beam is effectively projected to a road surface after light distribution, and a rectangular light spot is formed so as to be suitable for the wide road working condition.

As shown in fig. 17, 18 and 19, the pseudo color representation, the isolux chart and the spotlighting chart are obtained by mounting the lamphead of the street lamp of the present embodiment on a lamppost with a height of 12 m, applying the lamppost to a road with a width of 42 m (twelve lanes), mounting the street lamp on one side, and setting the distance between two street lamps to be 35 m (namely, setting the ratio of the distance between two lamps to the height of the lamps to be 2.92). When the street lamp holder is installed in the lamp pole, lens unit minor axis direction sets up just along road width direction lens unit minor axis positive direction is middle towards the road (with Y to positive), lens unit major axis direction sets up along road length direction. From the drawing can learn, the lens unit and the characteristics such as lens subassembly grading angle that this street lamp used are accurate, and the astigmatism is minimum, light utilization ratio is high, energy-conservation can satisfy CJJ45-2015 all index requirements completely (minimum illuminance/average illuminance is 0.721 and is greater than national standard requirement 0.4), promptly the utility model discloses a satisfy the illumination needs of wide way operating mode and improve illumination efficiency effectively through reasonable grading angle.

The above-mentioned embodiment is only the preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above-mentioned embodiment, and to the ordinary skilled person in the art, without departing from the present invention, a plurality of improvements and decorations on the premise of the principle should also be regarded as belonging to the technical solution disclosed by the technical solution of the present invention, and included in the protection scope of the present invention.

Claims

1. A lens unit applied to wide-path working conditions, the lens unit is provided with an inner cavity used for accommodating a light-emitting device, the lens unit comprises an incident surface and an emergent surface, the incident surface is located on the inner surface of the lens unit, the emergent surface is located on the outer surface of the lens unit, the incident surface is a concave free-form surface, and the emergent surface is a convex free-form surface;

the method is characterized in that:

2. The lens unit of claim 1, wherein a projection of the center of the light emitting device onto the bottom plane of the lens unit is spaced from a geometric center of the bottom plane of the lens unit by a distance L of 0.2 mm L2 mm.

3. The lens unit of claim 2, wherein a projection of the center of the light emitting device onto the bottom plane of the lens unit is spaced from a geometric center of the bottom plane of the lens unit by a distance L of 0.2 mm L1.5 mm.

4. The lens unit of claim 2, wherein a projection of the center of the light emitting device onto the bottom plane of the lens unit is spaced from a geometric center of the bottom plane of the lens unit by a distance L that satisfies 1.5 mm < L ≦ 2 mm.

5. The lens unit according to any one of claims 1 to 4, wherein the light beam emitted from the light emitting device is incident on the incident surface at an incident angle ranging from-60 ° to 60 °, is refracted at a refraction angle ranging from-52.362 ° to 59.536 °, and exits from the exit surface at an exit angle ranging from-63.23 ° to 66.65 °.

6. The lens unit according to claim 1 or 2, wherein when L is 0.2 mm, the contour lines of the free-form surface of the incident surface and the free-form surface of the exit surface in the respective planes meet the following light distribution condition;

7. The lens unit according to claim 1 or 2, wherein when L is 1.5 mm, the contour lines of the free-form surface of the incident surface and the free-form surface of the exit surface in the respective planes meet the following light distribution condition;

8. The lens unit according to claim 1 or 2, wherein when L is 2 mm, the contour lines of the free-form surface of the incident surface and the free-form surface of the exit surface in the respective planes meet the following light distribution conditions;

9. A lens unit according to any one of claims 1-4, characterized in that:

two positioning mounting columns protruding out of the bottom plane of the lens are arranged on the lens unit.

10. The lens unit of claim 9, wherein:

the two positioning mounting columns are symmetrically arranged at two ends of the long axis of the lens unit or on the extension line of the long axis.

11. The lens unit of claim 9, wherein: a convex rib is arranged on the periphery of the positioning mounting column; an included angle is formed between the center line of the convex rib arranged on the two positioning mounting columns and the plane formed by the axes of the corresponding positioning mounting columns.

12. A lens assembly for use in a wide-path condition, the lens assembly comprising a plurality of lens units, wherein the lens units are as claimed in any one of claims 1 to 11; and the plurality of lens units are arranged on the lens component in a consistent installation form.

13. The lens assembly of claim 12, wherein:

the lens assembly further comprises a substrate, a plurality of lens units are arranged on the substrate, and the plurality of lens units are uniformly distributed along the circumference or are sequentially distributed along the same direction.

14. A street lamp cap applied to wide road working conditions, comprising a top cover, a lampshade, a lamp holder and a lens unit, wherein the lens unit is the lens unit as claimed in any one of claims 1 to 11.

15. The street light head of claim 14, wherein: the lens units are multiple, and the installation forms of the lens units are consistent when the lens units are arranged on the lamp holder of the street lamp.

16. The street light head according to claim 14 or 15, characterized in that:

when the street lamp holder is applied to the actual scene, lens unit minor axis direction sets up just along road width direction lens unit minor axis positive direction is towards the road in the middle of, lens unit major axis direction sets up along road length direction.