TWI575190B - Lens with reduced thickness and optical unit having the same - Google Patents

Description

Lens and optical unit having the same

The present invention relates to a lens, and more particularly to a lens applied to an optical unit.

Generally, the light emitted by the light-emitting diode is relatively concentrated, and the light is not uniformly distributed when applied to the lamp. Therefore, the secondary optics principle is mostly used, and the lens is used to adjust the projection direction of the light. Since the light is incident on the lens, offset refracting is usually performed, and the curvature and thickness of the lens are usually used to form a desired light shape or to increase the uniformity of the light.

An embodiment of the invention discloses a lens suitable for controlling the light distribution of a light source. The lens comprises a lens body. The lens body includes a light exiting surface that is smooth and curved away from the light source, and a surface opposite to the light exiting surface and adjacent to the light source Into the glossy surface. The light incident surface has a plurality of curved surface portions facing the light source, and a plurality of engaging surface portions that connect adjacent curved curved portions. Each of the engaging faces has a first engaging edge and a second engaging edge respectively engaging the opposite sides of the adjacent curved surface portions, and the distance between the first engaging edge and the light source is different from the distance between the second connecting edge and the light source the distance.

Another embodiment of the invention discloses an optical unit comprising a housing, a light source, and the lens. The housing defines an accommodation space. The light source is disposed in the accommodating space of the outer casing. The lens cover is disposed on the light source.

1‧‧‧ lens

100‧‧‧ lens

11‧‧‧ lens body

110‧‧‧ bottom edge

111‧‧‧Glossy surface

112‧‧‧Into the glossy surface

112a‧‧‧Into the glossy surface

113‧‧‧Face Parts

114‧‧‧Connecting the face

115‧‧‧First connecting edge

116‧‧‧Second connection edge

10‧‧‧ Optical unit

2‧‧‧Light source

21‧‧‧Array Light Emitting Diodes

3‧‧‧ Shell

31‧‧‧ accommodating space

4‧‧‧reflector

41‧‧‧ Cover

411‧‧‧ first open end

412‧‧‧second open end

B‧‧‧Minimum distance

B’‧‧‧ Distance from the source to the curved surface

Q‧‧‧ axis

A‧‧‧ angle

Other features and effects of the present invention will be apparent from the following description of the drawings. FIG. 1 is a top plan view of an embodiment of a lens of the present invention; FIG. 2 shows the lens along the DD' of FIG. FIG. 3 is a side view of a relative position of a conventional lens and a light source; FIG. 4a is a light intensity distribution diagram of the conventional lens of FIG. 3 with the light source; FIG. 4b Is an optical intensity distribution diagram of the embodiment of the lens of FIG. 2 with the light source; FIG. 5a is a light pattern generated by simulating the conventional lens of FIG. Figure 5b is a top view of a lamp used to simulate the embodiment of the lens of Figure 2; Figure 6 is a bottom view of another embodiment of a lens of the present invention; Figure 7 shows the lens and a light source of Figure 6. Figure 8 is a side elevational view of another embodiment of the lens of Figure 6; Figure 9 is a side elevational view of another embodiment of the lens of Figure 6 as viewed from another angle; 10a is a side view showing a light-emitting route formed by using another conventional lens in a street lamp; FIGS. 10b to 10d are side views showing a light-emitting route formed by a street lamp using another embodiment of the lens of FIG. , respectively, is short, medium and long light distribution of the analog street lamp; FIG. 11a is a light intensity distribution diagram simulated by using the other conventional lens in the street lamp; FIG. 11b to FIG. 11d are simulations using the FIG. Another embodiment of the lens is a light intensity distribution map generated by the street lamp, which is respectively short, medium and long light distribution of the analog street lamp; FIG. 12a is a light pattern generated by simulating the use of a conventional lens in the street lamp; Figures 12b to 12d are simulations using the same as shown in Figure 6. Another embodiment of the lens is a light pattern generated by the street lamp, which is respectively short, medium and long light distribution of the analog street lamp; FIG. 13 is a schematic view of a side view light path of an embodiment of the optical unit of the present invention; Figure 14 is a side elevational view of another embodiment of the optical unit of the present invention; and Figure 15 is a schematic illustration of the use of another embodiment of the lens of Figure 6 in a street light.

Before the present invention is described in detail, it should be noted that in the following description, similar elements are denoted by the same reference numerals.

Referring to Figures 1 and 2, an embodiment of the lens 1 of the present invention is applicable to a light source 2 such as a light-emitting diode for controlling the light distribution of the light source 2.

2 is a schematic cross-sectional view of the lens of FIG. 1 taken along line DD' and a relative position of a light source. The lens 1 includes a lens body 11 including a light exit surface 111 having a smooth curved surface and away from the light source 2. And a light incident surface 112 opposite to the light exit surface 111 and adjacent to the light source 2. The light incident surface 112 has a plurality of curved surface portions 113 facing the light source 2, and a plurality of engaging surface portions 114 that connect the adjacent curved surface portions 113. Each of the engaging faces 114 has a first engaging edge 115 and a second engaging edge 116 (see FIG. 2) that respectively connect the opposite ends of the two adjacent curved portions 113. Because the distance between the curved surface portions 113 and the light source 2 is not uniform, the distance between the first connecting edge 115 of each connecting surface portion 114 and the light source 2 is different from the distance between the second connecting edge 116 and the light source 2 the distance.

In the present embodiment, each of the curved surface portions 113 has a ring shape. The light-emitting surface 111 of the lens body 11 has an arcuate shape, and each curved surface portion 113 of the light-incident surface 112 has an arcuate shape that protrudes toward the light-emitting surface 111. The area of the curved surface portion 113 of the light incident surface 112 is gradually increased toward the bottom edge 110 of the lens main body 11, and the tangential slope of the center of the curved surface portion 113 of the light incident surface 112 is toward the bottom edge 110 of the lens main body 11. Gradually increase. In some embodiments, the curvature of the light-emitting surface 111 is changed as needed, and the curved surface portions 113 are not limited to being arched toward the light-emitting surface 111.

In this embodiment, the light incident surface 112 of the lens 1 has seven curved surface portions 113. In some embodiments, the number of the curved surface portions 113 is not limited thereto, and may be according to the size and shape of the lens main body 11. And the shape of the light to be formed to make design adjustments.

In the embodiment, the center of each curved surface portion 113 is used as a basis for measuring the distance, and the curved surface portions 113 respectively have a distance from the light emitting surface 111, and the light source 2 and the curved surface portions 113 respectively have another A distance, wherein the light source 2 and the curved surface portions 113 respectively have a minimum ratio of the distance between the curved surface portions 113 and the light exiting surface 111, respectively.

A distance B shown in FIG. 2 is the minimum distance between the curved surface portion 113 and the light-emitting surface 111 in the embodiment. Further, the light source 2 has a distance B' from the curved surface portion 113 defining the distance B. In the present embodiment, the ratio of B' to B is about 1. In this embodiment, the lens 1 is made in an integrally formed manner, and the ratio is less than 1 This can result in waste of materials, increase the time for molding the mold, and increase the probability of deformation of the lens body 11.

4a and 4b are respectively a light intensity distribution diagram of the conventional lens 100 of Fig. 3 and the lens 1 of the present embodiment. The conventional lens 100 has the light-emitting surface 111 and a light-incident surface 112a which is opposite to the light-emitting surface 111 and has a smooth curved surface.

FIG. 5a and FIG. 5b are respectively a light pattern generated when the conventional lens 100 and the lens 1 of the embodiment are mounted on a street lamp. As shown in Figures 4b and 5b, the lens 1 disclosed in the present invention can produce a light intensity distribution and a light shape similar to the conventional lens 100 of Figures 4a and 5a, but compared to the conventional lens 100. The lens body 11 of the lens 1 disclosed in the present invention has a thinner thickness, thereby reducing the weight of the lens 1 and saving the material used in the production and achieving the effect of making the lens 1 thin.

Referring to Figures 6, 7, 8, and 9, another embodiment of the lens 1 of the present invention is substantially the same as the foregoing embodiment, except that in the present embodiment, each of the light incident surfaces 112 of the lens body 11 is One curved surface portion 113 has a plurality of sides and has 1152 curved surface portions 113. In this embodiment, the light source is an array of light emitting diodes 21. Specifically, in the present embodiment, each curved surface portion 113 has four sides. In still another embodiment of the present invention, each curved surface portion 113 can be designed to have three sides as needed. In still another embodiment of the present invention, each curved surface portion 113 has six sides, that is, each curved surface portion 113 is not limited to four sides.

Referring to Figures 10a-10d, Figures 11a-11d and Figures 12a-12d, another embodiment of the lens 1 is simulated using an optical software (Lighttools, Synopsys) in accordance with ANSI/IESNA The RP-8-14 road lighting standard is defined as Short, Medium, and Long longitudinal distribution range. Among them, the maximum light intensity projection distance of the short light distribution is less than 2.25MH (Mounting height), the maximum light intensity projection distance of the medium light distribution is 2.25~3.75MH, and the maximum light intensity projection distance of the long light distribution is greater than 3.75. MH.

Figure 10a shows a simulated light path diagram using another conventional lens (not shown). 10b, 10c, and 10d respectively show a light-emitting path diagram of a short, medium, and long light distribution of another embodiment of the lens 1 disclosed in the present invention. Figure 11a shows a simulated light intensity profile using the other conventional lens. 11b, 11c, and 11d respectively show light intensity distribution diagrams of the short, medium, and long light distributions of another embodiment of the lens 1 disclosed in the present invention.

Figure 12a is a simulated light pattern using another conventional lens based on a 10 foot mounting height. 12b, 12c, and 12d respectively show the light patterns generated by the short, medium, and long light distributions of another embodiment of the lens 1 disclosed in the present invention.

From the above simulation results, it is shown that the lens 1 disclosed in the present invention can achieve the short, medium and long light distribution of the road and adjust the curvature of the curved surface portions 113 to meet the North American Institute of Lighting Engineering (IES). , Illuminating Engineering Society of North America) Standard light distribution of different types of streetlights.

Referring to Figure 13, an embodiment of an optical unit 10 of the present invention includes a housing 3, the light source 2, and the lens 1.

The outer casing 3 defines an accommodation space 31.

The light source 2 is disposed in the accommodating space 31 of the outer casing 3. In this embodiment, the light source 2 is a light emitting diode. In other embodiments, the light source 2 is not limited in form and may be an array of light emitting diodes.

The lens 1 is covered by the light source 2.

Based on an axis Q of the light source 2 and defined as 0°, the light exit angle of the light source 2 mainly falls between 0° and 60°, as shown by the angle a in FIG. It passes directly through the curved surface portion 113 of the light incident surface 112 and is emitted from the light exit surface 111. With the lens 1, the light can achieve a large angle of refraction.

Referring to Figure 14, another embodiment of the optical unit 10 of the present invention is substantially identical to the optical unit 10 of Figure 13, except that the optical unit 10 further includes a frustoconical reflector 4.

In this embodiment, the reflector 4 is located between the outer casing 3 and the lens 1 and is covered with the light source 2 for reflecting the light emitted by the light source 2 toward the light incident surface 112 of the lens 1. . The reflector 4 includes a cover 41 surrounding the light source 2. The cover 41 has a first portion that is connected to the outer casing 3 and away from the light incident surface 112 of the lens 1. An open end 411 and a second open end 412 opposite to the first open end 411 and adjacent to the light incident surface 112 of the lens 1 , the cover 41 from the first open end 411 toward the second open end 412 The direction gradually expands outward.

In the present embodiment, the outer casing 3 and the reflector 4 are separately manufactured. The material of the reflector 4 is made of aluminum and is manufactured by a rotary press. In other embodiments, the outer casing 3 and the reflector 4 may be integrally formed.

By the arrangement of the reflector 4, light having an exit angle falling between 60° and 90° is reflected in the reflector 4, and after passing through the curved surface portion 113 of the lens 1, the light exit surface is refracted at a large angle. 111. In this way, the light output of 60°-90° can be effectively reduced, and the light is concentrated downwardly, and when the optical unit 10 is applied to outdoor illumination, the light can be uniformly spread and irradiated on the road surface.

Fig. 15 is a schematic view showing the application of another embodiment of the lens 1 to a street lamp.

In summary, the lens 1 of the present invention can reduce the thickness of the lens 1 and reduce the volume and weight of the lens 1 by the design of the curved surface portions 113 of the light incident surface 112, and can also increase the lens. The degree of freedom of use of the inner space and the light of the optical unit 10 having the lens 1 can be uniformly diffused and irradiated onto the road surface.

However, the above description is only for the embodiments of the present invention, and the scope of the present invention cannot be limited thereto, and the scope and patent description of the patent application according to the present invention. The simple equivalent changes and modifications made by the contents of the book are still within the scope of the invention patent.

1‧‧‧ lens

11‧‧‧ lens body

110‧‧‧ bottom edge

111‧‧‧Glossy surface

112‧‧‧Into the glossy surface

113‧‧‧Face Parts

114‧‧‧Connecting the face

115‧‧‧First connecting edge

116‧‧‧Second connection edge

2‧‧‧Light source

B‧‧‧Minimum distance

B’‧‧‧ Distance from the source to the curved surface

Claims (10)

A lens adapted to control a light distribution of a light source, the lens comprising: a lens body, the lens body comprising a light exit surface having a smooth curved surface and away from the light source, the light exit surface being arched; and an opposite The light-emitting surface is adjacent to the light-incident surface of the light source, wherein the light-incident surface has a plurality of curved surface portions facing the light source and a plurality of engaging surface portions connecting adjacent curved curved portions, wherein each of the engaging surface portions has two adjacent joints a first connecting edge and a second connecting edge opposite to the curved surface portion, the distance between the first connecting edge and the light source is different from the distance between the second connecting edge and the light source, wherein the light incident surface Each of the curved surface portions is annular and has an arcuate arch shape protruding toward the light emitting surface. The surface of the curved surface portion is different from a bottom edge of the lens body, and the surface of the curved surface portion is toward the bottom edge of the lens body. Gradually increase. The lens of claim 1, wherein each curved surface portion of the light incident surface has a plurality of sides. The lens of claim 1, wherein the center of each curved surface portion is a distance measurement reference, and the curved surface portions respectively have a distance from the light emitting surface, and the light source and the curved surface portions respectively have another The distance, wherein the light source and the curved surface portion respectively have the other distance, and the ratio of the distance between the curved surface portion and the light emitting surface respectively comprises a minimum of about 1. The lens according to claim 1, wherein a tangential slope of a center of the curved surface portion of the light incident surface is gradually increased toward the bottom edge of the lens main body. An optical unit comprising: a housing defining an accommodating space; a light source disposed in the accommodating space of the housing; and a lens according to claim 1, wherein the lens cover is disposed on the light source. The optical unit of claim 5, further comprising a reflector disposed between the light source and the lens, and covering the light source for reflecting the light emitted by the light source toward the lens Into the glossy surface. The optical unit of claim 6, wherein the reflector comprises a cover surrounding the light source, the cover having a first open end coupled to the housing and remote from the light incident surface of the lens, and a reverse The cover body gradually expands outward from the first open end toward the second open end at the first open end and adjacent to the second open end of the light incident surface of the lens. The optical unit of claim 6, wherein the outer casing and the reflector are integrally formed. The optical unit of claim 5, wherein the light source is a light emitting diode. The optical unit of claim 5, wherein the light source is an array of light emitting diodes.