A lens and lighting device

Abstract

The embodiment of the present application relates to the technical field of optical design, and discloses a lens and an illuminating device.The lens comprises an incident light side surface and an emergent light side surface; the incident light side surface comprises a first curved surface and a second curved surface which is connected with the periphery of the first curved surface and surrounds the first curved surface; the emergent light side surface comprises a third curved surface and a fourth curved surface which is connected with the periphery of the third curved surface and surrounds the third curved surface; the fourth curved surface comprises a reflection area which extends from the periphery of the third curved surface to a direction away from the optical axis, and a transmission area which extends from the reflection area to a direction away from the optical axis and is connected with the periphery of the second curved surface; light from the incident light side is incident into the lens through the first curved surface, part of the light incident into the first curved surface is emitted through the third curved surface, and the other part of the light incident into the first curved surface is sequentially incident into the reflection area, is reflected by the reflection area and then is incident into the second curved surface, is reflected by the second curved surface and then is incident into the transmission area and is emitted through the transmission area.The light passing through the lens has a large deflection angle and a high light emission efficiency.

Description

Technical Field

[0001] The present invention relates to the field of optical design technology, and in particular to a lens and an illumination device. Background Technology

[0002] Conventional LEDs have a Lambertian beam pattern. When Lambertian light shines on a flat surface, it typically creates a light spot that is bright in the center and dark at the edges. Therefore, lighting fixtures on the market often suffer from vignetting, making it impossible to achieve uniform illuminance and negatively impacting the user experience. To solve this technical problem, features such as... Figure 1 The conventional lens shown is used to deflect light rays in order to compensate for vignetting at the edges of the light spot.

[0003] However, the inventors have discovered at least the following problems in the related technology: See Figure 2 Because conventional lenses have a small deflection angle, the light rays exit at a small angle and the number of rays deflected to the edge of the light spot is small. Consequently, the ability to compensate for the dark corners at the edge of the light spot is low, resulting in low light extraction efficiency.

[0004] Therefore, there is an urgent need for a lens that has a large light deflection angle and high light extraction efficiency. Summary of the Invention

[0005] The purpose of this invention is to provide a lens with a large light deflection angle and high light extraction efficiency.

[0006] To address the aforementioned technical problems, embodiments of the present invention provide a lens, comprising an incident light-side surface and an exit light-side surface disposed opposite to each other along the optical axis; the incident light-side surface includes a first curved surface and a second curved surface that contacts and surrounds the first curved surface; the exit light-side surface includes a third curved surface and a fourth curved surface that contacts and surrounds the third curved surface; the first curved surface and the third curved surface are disposed opposite to each other along the optical axis and are both concave towards each other, the center point of the first curved surface and the center point of the third curved surface are both located on the optical axis; the second curved surface and the fourth curved surface are disposed opposite to each other along the optical axis and are both concave towards each other. The second curved surface protrudes away from each other, and the periphery of the second curved surface is connected to the periphery of the fourth curved surface; in the radial section of the lens, the fourth curved surface includes a reflective area extending from the periphery of the third curved surface in a direction away from the optical axis, and a transmissive area extending from the reflective area in a direction away from the optical axis and connected to the periphery of the second curved surface; light rays from the incident light side enter the lens through the first curved surface, part of the light rays entering the first curved surface exit through the third curved surface, and the other part of the light rays entering the first curved surface sequentially enter the reflective area, are reflected by the reflective area and then enter the second curved surface, are reflected by the second curved surface and then enter the transmissive area and are transmitted out through the transmissive area.

[0007] Compared with the prior art, the embodiments of the present invention allow other light rays entering the first curved surface to complete a secondary reflection path through the reflection area, the second curved surface, and the transmission area. The light rays that are reflected twice are finally emitted through the transmission area of ​​the outermost region of the light-emitting side surface, instead of being concentrated in the central region of the light-emitting side surface. This results in the light rays passing through the lens having a larger deflection angle, thereby increasing the number of light rays deflected to the edge of the light spot, improving the ability to compensate for the dark corner of the light spot edge, increasing the uniformity of the light spot illumination, and making the light have a higher light emission efficiency.

[0008] Furthermore, in the radial cross-section of the lens, both the reflective area and the transmissive area are rotationally symmetrical with respect to the optical axis; and the lens is integrally formed. This arrangement ensures that the fourth curved surface is rotationally symmetrical with respect to the optical axis, and that the lens itself is rotationally symmetrical with respect to the optical axis. When a rotationally symmetrical light spot needs to be formed, the light rays passing through the lens will compensate for the vignetting at the edge of the light spot with respect to the optical axis, thereby making the illumination of the light spot formed by the lens more uniform.

[0009] In addition, the curvature range of the first surface is set at 0.5mm. -1 ~1mm -1In this way, while ensuring that the light rays incident on the first curved surface can also enter the third and fourth curved surfaces, the curvature of the first curved surface is kept within a small range, thereby making the first curved surface more gentle, reducing the influence of the curvature of the first curved surface on the lens thickness, and making the overall lens thinner.

[0010] In addition, the curvature range of the second surface is set at 0.01mm. -1 ~0.2mm -1 In this way, while ensuring that the second curved surface can reflect light onto the transmission area of ​​the fourth curved surface, the curvature of the second curved surface is kept within a small range, thereby making the second curved surface smoother and reducing the influence of the curvature of the second curved surface on the lens thickness, making the overall lens thinner.

[0011] In addition, the curvature of the third surface is less than 0. Thus, the convex side of the third surface is opposite to the convex side of the fourth surface, so as to ensure that some of the light emitted from the first surface can exit through the third surface, while greatly reducing the influence of the third surface on the lens thickness, making the overall lens thinner.

[0012] In addition, the curvature range of the reflective zone is set at 0.09 mm. -1 ~0.3mm -1 In this way, while ensuring that the reflection area of ​​the fourth curved surface can reflect light onto the second curved surface, the curvature of the reflection area is kept within a small range, thereby making the reflection area more gentle and reducing the influence of the curvature of the reflection area on the lens thickness, making the overall lens thinner.

[0013] In addition, the curvature range of the transmission zone is set at 0.15 mm. -1 ~0.25mm -1 In this way, while ensuring that the transmission area of ​​the fourth curved surface can transmit the light reflected from the second curved surface, the curvature of the transmission area is kept within a small range, thereby making the transmission area more gentle and reducing the influence of the curvature of the transmission area on the lens thickness, making the overall lens thinner.

[0014] In addition, along the axial direction of the lens, the thickness of the lens at each point is not less than 2 mm; along the radial direction of the lens, the distance from the center point of the lens to its outer periphery is not less than 8 mm.

[0015] In addition, the refractive index of the lens is set between 1.49 and 1.68.

[0016] Embodiments of the present invention also provide an illumination device including any of the lenses described above. In this illumination device, a portion of the light rays in the lens are transmitted after undergoing a double refraction. The double-refractionated light rays ultimately exit through the transmission zone of the outermost region of the light-emitting side surface, instead of concentrating in the central region of the light-emitting side surface. This results in the lens of the illumination device having a larger light deflection angle, improving the ability to compensate for vignetting at the edge of the light spot, and thus achieving higher light extraction efficiency. Furthermore, in the same illumination device, compared to a conventional lens that can only perform a single refraction, because this lens requires a double refraction path, the curvature of the light-incident and light-emitting side surfaces of the lens is smaller, making the lens smoother and thinner, thereby making the internal structure of the illumination device more compact. Attached Figure Description

[0017] One or more embodiments are illustrated by way of example with reference numerals in the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Elements with the same reference numerals in the drawings are denoted as similar elements. Unless otherwise stated, the figures in the drawings are not to be limited by scale.

[0018] Figure 1 This is a schematic diagram of the structure of a conventional lens in the prior art;

[0019] Figure 2 This is a schematic diagram of the optical path of a conventional lens in existing technology;

[0020] Figure 3 This is a schematic diagram of the lens structure provided in an embodiment of the present invention;

[0021] Figure 4 This is a schematic diagram of the optical path of a lens structure provided in an embodiment of the present invention;

[0022] Figure 5 This is a schematic diagram of the optical path of another lens structure provided in an embodiment of the present invention;

[0023] Figure 6 This is a schematic diagram of the light spot formed by light passing through an ordinary lens;

[0024] Figure 7 This is a schematic diagram of the light spot formed by light passing through the lens provided in the embodiment of the present invention.

[0025] Figure label:

[0026] 10: Surface on the light-incident side; 110: First curved surface; 120: Second curved surface;

[0027] 20: Light-emitting side surface; 210: Third curved surface; 220: Fourth curved surface; 221: Reflection zone; 222: Transmission zone. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the various embodiments of the present invention will be described in detail below with reference to the accompanying drawings. However, those skilled in the art will understand that many technical details have been presented in the various embodiments of the present invention to enable the reader to better understand this application. However, the technical solutions claimed in this application can be implemented even without these technical details and various changes and modifications based on the following embodiments.

[0029] In embodiments of the present invention, the terms "upper," "lower," "left," "right," "front," "rear," "top," "bottom," "inner," "outer," "middle," "vertical," "horizontal," "lateral," and "longitudinal" indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings. These terms are primarily for the purpose of better describing the present invention and its embodiments, and are not intended to limit the indicated devices, elements, or components to having a specific orientation, or to be constructed and operated in a specific orientation.

[0030] Furthermore, in addition to indicating direction or positional relationship, some of the aforementioned terms may also have other meanings. For example, the term "above" may also be used in certain situations to indicate a dependency or connection. Those skilled in the art can understand the specific meaning of these terms in this invention based on the specific circumstances.

[0031] Furthermore, the terms "installation," "setting," "equipped with," "opening," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral structure; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium, or an internal connection between two devices, components, or parts. Those skilled in the art can understand the specific meaning of these terms in this invention according to the specific circumstances.

[0032] Furthermore, the terms "first," "second," etc., are primarily used to distinguish different devices, elements, or components (which may be the same or different in specific type and construction), and are not intended to indicate or imply the relative importance or quantity of the indicated devices, elements, or components. Unless otherwise stated, "a plurality of" means two or more.

[0033] An embodiment of the present invention provides a lens, see below. Figure 3It includes an incident light-side surface 10 and an exit light-side surface 20 arranged opposite each other along the optical axis; the incident light-side surface 10 includes a first curved surface 110 and a second curved surface 120 that is in contact with and surrounds the first curved surface 110; the exit light-side surface 20 includes a third curved surface 210 and a fourth curved surface 220 that is in contact with and surrounds the third curved surface 210; the first curved surface 110 and the third curved surface 210 are arranged opposite each other along the optical axis and are both recessed toward each other, the first curved surface 110... The center point of surface 10 and the center point of the third surface 210 are both located on the optical axis; the second surface 120 and the fourth surface 220 are arranged opposite each other in the optical axis direction and both protrude in a direction away from each other, with the periphery of the second surface 120 and the periphery of the fourth surface 220 in contact; in the radial section of the lens, the fourth surface 220 includes a reflection area 221 extending from the periphery of the third surface 210 in a direction away from the optical axis, and a transmission area 222 extending from the reflection area 221 in a direction away from the optical axis and in contact with the periphery of the second surface 120; see also Figure 4 and Figure 5 Light rays from the incident light side enter the lens through the first curved surface 110. Part of the light rays entering the first curved surface 110 exit through the third curved surface 210. The other part of the light rays entering the first curved surface 110 are sequentially incident on the reflection area 221, reflected by the reflection area 221, incident on the second curved surface 120, reflected by the second curved surface 120, incident on the transmission area 222, and transmitted out through the transmission area 222.

[0034] Compared to the prior art, in the embodiments of the present invention, other portions of the light rays incident on the first curved surface 110 can complete a secondary reflection path through the reflection area 221, the second curved surface 120, and the transmission area 222. The light rays that are reflected twice are finally emitted through the transmission area 222 of the outermost region of the light-emitting side surface 20, instead of being concentrated in the central region of the light-emitting side surface 20. This results in the light rays passing through the lens having a larger deflection angle, thus giving the lens a stronger beam-expanding capability, improving the compensation capability for the dark corners at the edge of the light spot, increasing the uniformity of the light spot illumination, and thereby giving the light rays a higher light extraction efficiency. Specifically, see Figure 6 and Figure 7 , Figure 6 This is a schematic diagram of the light spot formed by light passing through an ordinary lens. Figure 7 This is a schematic diagram of the light spot formed by light passing through the lens provided in the embodiment of the present invention. Through experimental comparison, the illuminance of the light spot formed after passing through the lens of the present invention is greatly improved (about 10 times), and the illuminance of the light spot is also more uniform. Therefore, the lens of the present invention has a high light emission efficiency.

[0035] Furthermore, in the same application scenario, compared to conventional lenses that can only perform single refraction, this lens can achieve a secondary reflection optical path. Therefore, the curvature of the light-incident surface 10 and the light-outcrystal surface 20 of the lens is smaller, resulting in a smoother and thinner lens. The secondary reflection optical path of this lens is achieved through reflection and refraction of its own curved surface, without the need for coating on the lens, thus giving it the advantage of low cost.

[0036] Specifically, when it is necessary to form a light spot that is rotationally symmetrical with respect to the optical axis, see [reference needed]. Figure 4 On the radial cross section of the lens, the fourth curved surface 220 includes a reflection area 221 and a transmission area 222 on both the upper and lower sides of the optical axis, making the reflection area 221 and the transmission area 222 rotationally symmetrical with respect to the optical axis. Therefore, the fourth curved surface 220 is rotationally symmetrical with respect to the optical axis, and the lens is rotationally symmetrical with respect to the optical axis. The light rays passing through the lens will compensate for the dark angle at the edge of the light spot with rotational symmetry with respect to the optical axis, thereby making the illumination of the light spot formed by passing through the lens more uniform.

[0037] In another implementation, see Figure 5 The fourth curved surface 220 includes a reflection area 221 and a transmission area 222 on the upper side of the optical axis, and a conventional curved surface on the lower side of the optical axis. This allows light rays incident on the upper side of the optical axis to undergo a second reflection after passing through the reflection area 221, the second curved surface 120, and the transmission area 222 before being transmitted. Light rays incident on the lower side of the optical axis undergo a single refraction before being transmitted. Because the offset angles of the light rays incident on the upper and lower sides of the optical axis are different, the transmitted light rays form an off-center light spot. Alternatively, the lens can be designed as a combination of a double-reflection optical path structure and other structures. By adjusting the curvature and refractive index of each surface of the lens, the offset angles of different light rays passing through the lens can be adjusted, thereby forming non-rotationally symmetric light spots and rectangular light spots, etc. The specific design can be set according to actual design and usage requirements, and this embodiment does not impose specific limitations on this.

[0038] More specifically, the various curved surfaces of the lens can be connected by means of bonding or other methods, or they can be integrally formed. In this embodiment, the lens is integrally formed.

[0039] The curvature range of the first surface 110 is set at 0.5mm. -1 ~1mm -1 Between, and the curvature of the first surface 110 can specifically be 0.5mm. -1 0.65mm -1 0.9mm -1 1mm -1In this way, while ensuring that the light rays incident on the first curved surface 110 can also enter the third curved surface 210 and the fourth curved surface 220, the curvature of the first curved surface 110 is kept within a small range, thereby making the first curved surface 110 more gentle, so as to reduce the influence of the curvature of the first curved surface 110 on the thickness of the lens, making the overall thickness of the lens thinner.

[0040] The curvature range of the second surface 120 is set at 0.01mm. -1 ~0.2mm -1 Between, and the curvature of the second surface 120 can specifically be 0.01mm. -1 0.09mm -1 0.15mm -1 0.2mm -1 In this way, while ensuring that the second curved surface 120 can reflect light onto the transmission area 222 of the fourth curved surface 220, the curvature of the second curved surface 120 is kept within a small range, thereby making the second curved surface 120 more gentle, so as to reduce the influence of the curvature of the second curved surface 120 on the lens thickness, making the overall lens thinner.

[0041] The curvature of the third surface 210 is less than 0, and specifically, the curvature of the third surface 210 can be -0.5mm. -1 -0.8mm -1 -1.2mm -1 -2mm -1 In this way, the convex side of the third curved surface 210 is opposite to the convex side of the fourth curved surface 220, so as to ensure that some of the light emitted from the first curved surface 110 can be emitted through the third curved surface 210, while greatly reducing the influence of the third curved surface 210 on the lens thickness, making the overall lens thinner.

[0042] The curvature range of the reflective area 221 is set at 0.09mm. -1 ~0.3mm -1 Between, and the curvature of the reflection area 221 of the fourth surface 220 can specifically be 0.09mm. -1 0.16mm -1 0.27mm -1 0.3mm -1 In this way, while ensuring that the reflection area 221 of the fourth curved surface 220 can reflect light onto the second curved surface 120, the curvature of the reflection area 221 is kept within a small range, thereby making the reflection area 221 more gentle, so as to reduce the influence of the curvature of the reflection area 221 on the thickness of the lens, making the overall lens thinner.

[0043] The curvature range of the transmission region 222 is set at 0.15mm. -1 ~0.25mm-1 Between. And the curvature of the transmission area 222 of the fourth curved surface 220 can specifically be 0.15mm. -1 0.19mm -1 0.23mm -1 0.25mm -1 In this way, while ensuring that the transmission area 222 of the fourth curved surface 220 can transmit the light reflected from the second curved surface 120, the curvature of the transmission area 222 is kept within a small range, thereby making the transmission area 222 more gentle, so as to reduce the influence of the curvature of the transmission area 222 on the thickness of the lens, making the overall thickness of the lens thinner.

[0044] The refractive index of the lens is set between 1.49 and 1.68. The refractive index at different curved surfaces of the lens can be the same or different. The specific refractive index of different curved surfaces can be set according to actual design and usage requirements. This embodiment does not make specific limitations on this.

[0045] More specifically, along the axial direction of the lens, the thickness at all points is not less than 2mm, and can specifically be 2mm, 3mm, 4.5mm, etc. Along the radial direction of the lens, the distance from the center point of the lens to its outer periphery is not less than 8mm, and can specifically be 8mm, 9.5mm, 12mm, etc. It should be noted that the curvature of each surface on the lens will have a certain impact on the thickness of the lens and the distance from the center point of the lens to its outer periphery. While meeting the requirements for the deflection angle of light passing through the lens, the smaller the curvature of each surface on the lens, the thinner the lens and the larger the distance from the center point of the lens to its outer periphery; conversely, the larger the curvature of each surface on the lens, the thicker the lens and the smaller the distance from the center point of the lens to its outer periphery. The specific values ​​can be set according to the actual application of the lens, and this embodiment does not impose specific limitations on this.

[0046] The present invention also provides a lighting device. Since the lens used in this lighting device is any of the aforementioned lenses, a portion of the light rays in the lens are transmitted after a second reflection. The light rays that are reflected twice ultimately exit through the transmission zone 222 of the outermost region of the light-emitting surface 20, instead of being concentrated in the central region of the light-emitting surface 20. This results in a larger light deflection angle in the lens of the lighting device, improving the compensation capability for vignetting at the edge of the light spot, and thus achieving higher light extraction efficiency. Furthermore, in the same lighting device, compared to a conventional lens that can only perform a single refraction, the lens of this lighting device requires a second reflection, resulting in a smaller curvature of the light-incident surface 10 and the light-emitting surface 20. This makes the lens flatter and thinner, reducing the space occupied by the lens within the lighting device and making the structure of the lighting device more compact.

[0047] This lighting device can be a ceiling light, table lamp, wall washer, or other lighting fixtures, such as an infrared doorbell. The number of lenses within the device can be one or more, depending on the actual design and usage requirements; this invention does not impose specific limitations. Taking the example of a lighting fixture with multiple lenses, the lenses are evenly arranged within the fixture according to its actual shape and the required light deflection angle. This improves the light fixture's ability to compensate for dark corners at the edges of light spots, thereby significantly improving the uniformity of illumination. Furthermore, because the lighting fixture with these lenses has a larger light deflection angle and higher illumination uniformity, it consumes less energy under the same illumination requirements, thus offering the advantage of low energy consumption. Additionally, the lenses are flatter and thinner, reducing the space they occupy within the lighting fixture, resulting in a more compact structure and smaller footprint.

[0048] The "subject name" provided by the embodiments of the present invention has been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only for the purpose of helping to understand the idea of ​​the present invention. There may be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A lens, characterized in that, This includes an incident light-side surface and an exit light-side surface that are arranged opposite to each other along the optical axis. The light-incident side surface includes a first curved surface and a second curved surface that is connected to and surrounds the first curved surface. The light-emitting side surface includes a third curved surface and a fourth curved surface that is connected to and surrounds the third curved surface. The first curved surface and the third curved surface are arranged opposite to each other in the direction of the optical axis and are both concave towards each other. The center point of the first curved surface and the center point of the third curved surface are both located on the optical axis. The second curved surface and the fourth curved surface are arranged opposite to each other in the optical axis direction and both protrude in a direction away from each other, and the periphery of the second curved surface is connected to the periphery of the fourth curved surface; In the radial cross-section of the lens, the fourth curved surface includes a reflective region extending from the periphery of the third curved surface in a direction away from the optical axis, and a transmissive region extending from the reflective region in a direction away from the optical axis and connecting with the periphery of the second curved surface. The curvature range of the reflective region is set at 0.09 mm. -1 ~0.3mm -1 The curvature range of the transmission zone is set between 0.15 mm. -1 ~0.25mm -1 between; Light rays from the incident light side enter the lens through the first curved surface. Part of the light rays entering the first curved surface are diffused by the first curved surface and exit through the third curved surface. The other part of the light rays entering the first curved surface are diffused by the first curved surface and sequentially enter the reflection area, are reflected by the reflection area and enter the second curved surface, are reflected by the second curved surface and enter the transmission area and are transmitted out through the transmission area.

2. The lens according to claim 1, characterized in that, In the radial cross-section of the lens, both the reflecting region and the transmitting region are rotationally symmetrical with respect to the optical axis; and, The lens is integrally formed.

3. The lens according to claim 1 or 2, characterized in that, The curvature range of the first surface is set at 0.5mm. -1 ~1mm -1 between.

4. The lens according to claim 1 or 2, characterized in that, The curvature range of the second surface is set at 0.01 mm. -1 ~0.2mm -1 between.

5. The lens according to claim 1 or 2, characterized in that, The curvature of the third surface is less than 0.

6. The lens according to claim 1 or 2, characterized in that, Along the axial direction of the lens, the thickness of the lens at all points is not less than 2 mm; Along the radial direction of the lens, the distance from the center point of the lens to its outer periphery is not less than 8 mm.

7. The lens according to claim 1 or 2, characterized in that, The refractive index of the lens is set between 1.49 and 1.

68.

8. A lighting device, characterized in that, Includes the lens as described in any one of claims 1-7.

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