CN108870319B

CN108870319B - Lighting lens and corresponding lighting unit

Info

Publication number: CN108870319B
Application number: CN201810684595.5A
Authority: CN
Inventors: 张发伟
Original assignee: Ningbo Self Electronics Co Ltd
Current assignee: Ningbo Self Electronics Co Ltd
Priority date: 2018-06-27
Filing date: 2018-06-27
Publication date: 2024-08-02
Anticipated expiration: 2038-06-27
Also published as: CN108870319A

Abstract

The invention relates to an illumination lens and a corresponding illumination unit, wherein the illumination is transparent, so that light rays are incident from an incident surface, reflected by a total internal reflection surface and then emitted from an emergent surface, and the light rays are emitted along the opposite direction of the incident light rays, thereby realizing indirect illumination of the top and greatly reducing glare.

Description

Lighting lens and corresponding lighting unit

Technical Field

The present invention relates to the field of optics, and in particular, to an illumination lens and a corresponding illumination unit for effectively reducing glare.

Background

The LED lamp is more and more commonly used in daily life work, especially in places such as markets and counters, which are severely dependent on light effects. In order to provide a good lighting effect, a user usually places a plurality of lamps on the counter or the corresponding surface of the installation object, but this also brings a lot of problems, especially the problem of glare, and when the lamps have too high brightness and too many lamps, the user can feel that the eyes are stained and the light is too strong.

In order to solve the problem, researchers often adopt a mode of replacing lamps and combining with cloth positions to try to provide reasonable angles, avoid light from directly irradiating eyes of people, and weaken direct stimulation to the eyes; or the lamp is subjected to anti-dazzle treatment to weaken the brightness of emergent light and soften the emergent light so as to achieve the purpose; or when the lamp is used, the lamp is made to illuminate according to the percentage of the maximum illuminance, namely, the allowance is reserved, and the problem of glare is solved by adjusting the illuminance, but the effect is often not ideal.

Thus, there is a need in the art for improved luminaire illumination that is effective in reducing glare and providing comfortable illumination.

Disclosure of Invention

In view of the foregoing, it is an object of the present invention to provide an illumination lens and a corresponding illumination unit capable of providing indirect illumination, reducing glare by controlling the angle of top flood illumination.

In general, in one aspect, an illumination lens of the present application includes an entrance face, a total internal reflection face on one side of the entrance face, and an exit face connected to the entrance face and the total internal reflection face;

the illumination lens is configured such that light rays are incident from the incident surface and reflected by the total internal reflection surface, and then guided to be emitted from the emergent surface along the direction opposite to the incident direction of the light rays, so as to provide secondary illumination.

In another aspect of the present application, an illumination unit is provided, where the illumination unit includes a light source and the illumination lens described above, and the light source is located on the incident surface side of the illumination lens.

Compared with the prior art, the invention has the advantages that: the light emitted by the light source is directly projected to an irradiated object, the incident light path direction is modified through the total internal reflection effect, the irradiation angle is controlled, the light is finally emitted along the opposite direction of the incident direction of the light after a series of reflection and refraction effects, the emitted light is projected to the irradiated object, the strong glare generated by direct primary irradiation of the light can be reduced, the light energy after multiple reflection or refraction can be attenuated, the comfortable irradiation feel can be provided when the attenuated light is secondarily illuminated, the glare is reduced, and the visual pressure formed by direct incidence is avoided.

Drawings

Fig. 1 is a diagram showing the structure of an illumination lens according to an embodiment of the present invention.

Fig. 2 is another angular block diagram of fig. 1.

Fig. 3 is a light path effect diagram corresponding to fig. 1.

Detailed Description

Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to like or similar elements or elements having like or similar functions throughout. The embodiments described below by referring to the drawings are illustrative only and are not to be construed as limiting the invention.

The illumination lens according to the present application has an entrance face 1 and an exit face 2 as a general lens, but the illumination lens according to the present application further comprises a total internal reflection face 3 at one side of the entrance face, the exit face 2 being connected to the entrance face 1 and the total internal reflection face 3, and the lens is thus capable of modifying a light path, controlling a light angle to cause light to be emitted in a direction opposite to an incident direction, thereby realizing indirect illumination of the top of the illumination device, and greatly reducing glare.

In one embodiment shown in fig. 1, the opposite side of the incidence plane 1 of the lens is provided with a total internal reflection plane 3, the total internal reflection plane 3 is connected to the incidence plane 1 through the emission plane 2, and the total reflection plane 3 is used for totally reflecting the light from the incidence plane 1 and re-emitting the light from the emission plane 2, see fig. 2. In order to ensure that the direction of the light emitted from the light emitting surface 2 is substantially opposite to that of the light incident on the light emitting surface 2, the angle between the light emitting surface 3 and the light emitting surface 1 is set to be the same as the angle of the light emitted from the light emitting surface 2 when the light enters from the light emitting surface 1 and is emitted to the light emitting surface 3, the incident angle of the light entering the light emitting surface 3 is greater than the critical angle, and the light emitting surface 2 and the light emitting surface 3 are required to be the same as the angle of the light emitted from the light emitting surface 2.

The light will have energy attenuation in the course of propagation, therefore, when the light beam enters the incident surface 1 initially, it has the largest energy, after undergoing a total internal reflection, the energy will be attenuated once, and then will be attenuated again when being emitted from the emergent surface, so far, the emergent light has a great attenuation relative to the incident light, in other words, when the incident light is directly projected to the irradiated object, the corresponding energy is the largest at this time, that is, the brightness at this time is the brightest, this will inevitably generate glare, resulting in visual pressure, while after the optical design of the illumination lens of the application is adopted, the ray path angle is controlled and changed, the light is "tamed", when the light is emitted again, the light becomes flexible, and the glare is greatly reduced.

The illumination lens of the application enables the incident angle and the emergent angle of light to be controllable, and when the angle designs among the emergent surface, the total internal reflection surface and the incident surface are different, the intensity and the direction of the finally led light are different, so that the illumination level and the glare level which are required to be achieved in actual use are freely selected according to the requirements at specific design moments, which is generally known to the person skilled in the art, and is not the key point of the application, and therefore, the application is not repeated here.

With continued reference to fig. 1 and 2, in this embodiment, the illumination lens is of symmetrical design, i.e., if referenced to a cartesian coordinate system, the illumination lens has a left half lens and a right half lens with a Z-axis as the axis of symmetry. In an embodiment, the incident surface 1 of the illumination lens is divided into a left incident surface 11 and a right incident surface 12 with the Z axis as the symmetry axis, as shown in fig. 1, and the incident surface 1 is a plane. It is conceivable that the entrance face may also be non-planar, such as a surface formed with a positive curvature approaching zero. The light source is positioned on the extension line of the Z axis, and the same optical effect can be realized due to the same structure of the left lens and the right lens.

The total internal reflection surface 3 comprises a first total internal reflection surface 31 located on the top surface of the incident surface 11, and a second total internal reflection surface 32 with two ends respectively connected with the first total internal reflection surface 31 and the emergent surface 2 and designed obliquely, the second total internal reflection surface 32 can reflect the light reflected by the first total internal reflection surface 31 again, and meanwhile, the angle of the light reflected by the first total internal reflection surface 31 is adjusted so that the light can be better emitted from the emergent surface 2 according to the requirement, for example, the inclined included angle formed by the second total internal reflection surface 32 and the first total internal reflection surface on the cross section shown in fig. 1 can be an obtuse angle, and at the moment, the included angle formed by the emergent surface 2 and the second total internal reflection surface on the cross section shown in fig. 1 needs to be correspondingly adjusted so as to ensure that the light can be emitted from the emergent surface 2 after secondary reflection.

In this embodiment, the surface of the first total internal reflection surface 31 is in an arc design with a positive curvature change, and the surface of the second total internal reflection surface 32 is slightly concave, so that when light is incident, the first total internal reflection surface 31 can also gather the light, thereby avoiding light loss caused by that part of the light cannot be reflected due to excessive disorder of the light; the second tir surface 32 also has a diverging effect, so that the light beam is emitted with a wider irradiation range. Preferably, the entrance surface 2 is also of slightly concave design. The lighting lens is of the symmetrical design, so that when light rays are emitted from the back surface of the light source, the light rays are not formed on the back surface of the light source, and meanwhile, the fact that the light emitting surface of the light source faces towards an irradiated object is avoided, and the glare problem can be further overcome.

Referring to fig. 2, the present embodiment provides an illumination unit, where the illumination unit includes a light source and the aforementioned illumination lens, and the light source is located in the Z-axis direction of the symmetry axis of the illumination lens. The light source can be an incandescent lamp, an LED light source, or other illumination light sources. It should be mentioned that the light source can be equivalent to a point light source, in order to ensure the effect and meet the requirement of high light efficiency of the system, the optimal size ratio of the light source to the total reflection surface of the lens is about 1:20, and of course, the optimal size ratio of the light source to the total reflection surface of the lens can be appropriately smaller than 1:20, but the size can be selected as long as the light source can be equivalently used as the point light source, and when the lens size is large enough, the light emitted by the point light source can be more comprehensively received, for example, the lens combination in the embodiment can focus the light within an included angle of 150 degrees, so that the loss is reduced.

Of course, the light source may also be located in the illumination lens, that is, the illumination lens is provided with a groove for accommodating the light source at the symmetry center of the incident surface, and the light of the light source is incident from the top surface of the groove and the rest of the incident surface. It is conceivable that the lighting unit further comprises other components, such as a lamp holder for arranging the light source, a lamp shade and a power lamp for powering the light source, and such components are not of importance for the present application and are not described in detail here.

The illumination unit is designed in such a way that light emitted by a conventional light source and directly projected to an irradiated object can be subjected to total internal reflection to modify the running direction, the irradiation angle is controlled, the light is emitted from the emergent surface in the opposite direction along the incidence direction of the light, the strong glare generated by direct primary irradiation of the light is reduced, the energy of the light after multiple reflection or refraction can be attenuated, comfortable irradiation feeling can be provided when the attenuated light is subjected to secondary illumination, and the visual pressure formed by direct incidence on the head is avoided.

In addition to the above-described modifications, other similar modifications are also included in the scope of the present invention, and will not be described in detail herein. While embodiments of the invention have been shown and described, it will be understood by those skilled in the art that: many variations, modifications, substitutions, and alterations are possible in these embodiments without departing from the principles and spirit of the invention.

Claims

1. An illumination lens comprises an incidence surface (1) and an emergent surface (2) with one end connected with the incidence surface (1);

The method is characterized in that:

The light-emitting device further comprises a total internal reflection surface (3) positioned at one side of the incidence surface (1), wherein the total internal reflection surface (3) is connected with the emergent surface (2);

the illumination lens is configured such that light rays are emitted from the incident surface (1) and reflected by the total internal reflection surface (3) and then guided to be emitted from the emergent surface (2) along the opposite direction of the incident direction of the light rays, so as to provide secondary illumination;

Wherein the total internal reflection surface (3) comprises a first total internal reflection surface (31) and a second total internal reflection surface (32) connected with the first total internal reflection surface (31);

The first total internal reflection surface (31) is positioned at the top of the incident surface (1), and the second total internal reflection surface (32) is respectively connected with the first total internal reflection surface (31) and the emergent surface (2) so as to provide secondary total reflection and guide light rays to be emitted from the emergent surface (2);

the first total internal reflection surface (31) is an arc surface with a positive curvature change, the second total internal reflection surface (32) is an arc surface with a negative curvature change, and the emergent surface (2) is an arc surface with a negative curvature change; wherein:

The illumination lens comprises a left half lens and a right half lens, and the left half lens and the right half lens are symmetrically designed;

the incident surface (1) of the illumination lens is a plane, and two incident surfaces corresponding to the left half lens and the right half lens are formed by taking the symmetry axis as the center.

2. A lighting unit comprising a lighting lens as claimed in claim 1 and a light source at the other side of the entrance face (1), characterized in that:

The light source may be equivalently a point light source.

3. A lighting unit comprising a lighting lens as claimed in claim 1 and a light source at the other side of the entrance face (1), characterized in that:

The light source may be equivalently a point light source, which is located on an extension of the symmetry axis.

4. A lighting unit as recited in claim 2 or claim 3, wherein:

The size ratio of the light source to the total reflection surface of the illumination lens is 1:20.