Variable focus optical system and luminaire
By combining a reflector, a convex lens, and a Fresnel lens in a variable-focus optical system, multiple light control and lossless zoom are achieved, solving the problems of light efficiency loss and fixed light control angle in existing LED spotlights, and improving light uniformity and light energy utilization.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- SICHUAN OUSHENG OPTICAL INSTR CO LTD
- Filing Date
- 2025-04-14
- Publication Date
- 2026-06-09
AI Technical Summary
In existing LED spotlights, total reflection lenses and reflectors have problems such as poor temperature resistance, heavy weight, large light efficiency loss, large light spot size, low light energy concentration, and fixed and unchangeable light control angle, making it impossible to achieve lossless zoom.
The system employs a variable-focus optical system, including a light source, a reflector, a convex lens, and a Fresnel lens. The reflector controls the light for the first time, the convex lens controls the light for the second time, and the Fresnel lens precisely controls the angle of light emission, thus achieving multiple light control and zoom. Furthermore, the distance between the Fresnel lens and the convex lens in the optical system is adjustable to achieve lossless zoom.
It achieves uniform light output, reduces light efficiency loss, and solves the problems of heavy weight, poor temperature resistance, and fixed light control angle, enabling controllable zoom without sacrificing light efficiency.
Smart Images
Figure CN224339970U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of lighting equipment technology, and in particular to a variable focus optical system and a lamp incorporating the variable focus optical system. Background Technology
[0002] In LED spotlights, total internal reflection lenses or reflectors are commonly used to control the illumination distance and area. However, both total internal reflection lenses and reflectors have their own drawbacks. Total internal reflection lenses are unsuitable for high-power lighting equipment due to their poor temperature resistance, and they are also relatively heavy, with a thicker central area resulting in significant light loss. Reflectors, on the other hand, have uncontrolled light at the center, leading to a larger light spot, lower light energy concentration, and poor light utilization. Furthermore, to achieve effective light control, reflectors are typically designed to be tall, increasing assembly requirements. Additionally, both total internal reflection lenses and reflectors have fixed, non-adjustable angles for light control, and while zoomable total internal reflection lenses exist, the issue of light loss remains unresolved.
[0003] Chinese invention patent application CN116592305A discloses an LED linear lighting optical system and a luminaire. In its technical solution, the optical system includes a first light distribution component and a second light distribution component. The first light distribution component includes a light collector and a light controller. The light collector includes linearly arranged light-collecting units, each used to mount at least one LED light source. The light controller includes linearly arranged light-controlling units, with a one-to-one correspondence between the light-collecting units and the light-controlling units. The second light distribution component includes a polarizing optical sheet or a light-uniforming optical sheet, and is located on the light-emitting side of the first light distribution component. Although this invention patent application improves light control by setting up light-collecting and light-controlling units, thus increasing the uniformity of light, its light control angle remains fixed, and it cannot achieve lossless zoom. Utility Model Content
[0004] The technical problem to be solved by this utility model is to provide a zoom optical system that can achieve zoom while avoiding loss of light effect.
[0005] To solve the above-mentioned technical problems, the technical solution adopted by this utility model is: a variable focus optical system, including a light source, a reflector, a convex lens, and a Fresnel lens arranged in sequence; the light source is close to the light inlet of the reflector, the plane of the convex lens is close to the light outlet of the reflector, the convex surface of the convex lens faces the Fresnel lens, the side of the Fresnel lens facing the convex lens is the light inlet surface, and the side of the Fresnel lens away from the convex lens is the light outlet surface; the distance between the Fresnel lens and the convex lens is adjustable.
[0006] As an improvement to the above scheme: the light-incident surface of the Fresnel lens is a beaded microstructure surface or a textured surface, and the light-exit surface of the Fresnel lens is a Fresnel surface.
[0007] As an improvement to the above solution, the light-incident surface of the Fresnel lens is an etched textured surface or a frosted textured surface.
[0008] As an improvement to the above scheme: the incident surface of the Fresnel lens is a polygonal compound eye microstructure surface or a Fermat spiral compound eye microstructure surface.
[0009] As an improvement to the above scheme: the outer contours of the convex lens and the Fresnel lens are both circular, and the reflector cup is a conical structure; the centers of the convex lens and the Fresnel lens are located on the central axis of the reflector cup.
[0010] As an improvement to the above scheme: the plane of the convex lens covers the light outlet of the reflector cup, and the Fresnel lens covers the convex surface of the convex lens.
[0011] As an improvement to the above solution, the light inlet of the reflector cup covers the light emission range of the light source.
[0012] This utility model also discloses a lamp, including the variable focus optical system as described above, and a focusing bracket. The light source, reflector and convex lens are all fixedly mounted on the focusing bracket, and the Fresnel lens is movably mounted on the focusing bracket. The Fresnel lens can be translated relative to the convex lens through the focusing bracket.
[0013] The beneficial effects of this invention are as follows: This invention controls the light emitted from the light source by using a reflector, a convex lens, and a Fresnel lens. This invention can control the light emitted from the light source multiple times. First, the reflector reflects the scattered light emitted from the light source, reducing the angle of the scattered light, thus focusing and controlling the scattered light to prevent further scattering. The light with the reduced angle then enters the convex lens, which controls all the light. Finally, since the distance between the Fresnel lens and the convex lens can be adjusted according to the control requirements of the light emission angle, the Fresnel lens can precisely control the light emission angle, effectively improving the uniformity of light emission and reducing light efficiency loss. This invention solves the problems of heavy weight and poor temperature resistance associated with the use of total internal reflection lenses in existing technologies, as well as the problems of difficult light control and low light spot utilization associated with the use of reflectors in existing technologies. It achieves controllable zoom without sacrificing optical efficiency. Attached Figure Description
[0014] Figure 1 This is a schematic diagram of the structure of this utility model;
[0015] Figure 2 A schematic diagram showing the light rays exiting when the Fresnel lens moves away from the convex lens;
[0016] Figure 3 A schematic diagram showing the light emitted when a Fresnel lens is brought close to a convex lens;
[0017] Figure 4 A schematic diagram of the first embodiment of the incident surface of a Fresnel lens;
[0018] Figure 5 A schematic diagram of a second embodiment of the incident surface of a Fresnel lens;
[0019] Figure 6 This is a schematic diagram of a third embodiment of the incident surface of a Fresnel lens.
[0020] The markings in the diagram are: 100 - light source, 200 - reflector, 300 - convex lens, 400 - Fresnel lens, 500 - ray. Detailed Implementation
[0021] To facilitate understanding of this utility model, the following description, in conjunction with the accompanying drawings, will provide further details.
[0022] In the description of this utility model, it should be noted that the terms "front", "rear", "left", "right", "up", "down", "inner", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of description and do not indicate or imply that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.
[0023] like Figures 1 to 3As shown, the variable focus optical system disclosed in this utility model consists of a light source 100, a reflector 200, a convex lens 300, and a Fresnel lens 400. The light source 100, reflector 200, convex lens 300, and Fresnel lens 400 are arranged sequentially, with the light outlet of the light source 100 close to the light inlet of the reflector 200, and the light outlet of the reflector 200 close to the convex lens 300. The two sides of the convex lens 300 are a plane and a convex surface, respectively. The plane of the convex lens 300 is close to the light outlet of the reflector 200, and the convex surface of the convex lens 300 faces the Fresnel lens 400. The two sides of the Fresnel lens 400 are an incident surface and an exit surface, respectively. The incident surface of the Fresnel lens 400 faces the convex surface of the convex lens 300, and the exit surface of the Fresnel lens 400 faces away from the convex surface of the convex lens 300. This invention uses a reflector 200, a convex lens 300, and a Fresnel lens 400 to sequentially control the light ray 500 emitted from the light source 100, achieving multiple light control of the light ray 500 and thus precisely controlling the emission angle of the light ray 500. Furthermore, the distance between the Fresnel lens 400 and the convex lens 300 in this invention can be adjusted according to the light control requirements, such as... Figure 3 and Figure 4 As shown, by adjusting the distance between the Fresnel lens 400 and the convex lens 300, the outgoing light path of the light ray 500 can be changed to achieve zoom; and there is no loss of light during this zoom process, achieving a lossless zoom effect.
[0024] Specifically, the structure of the light source 100 in this utility model is not limited. In the entire variable focus optical system, as long as it is ensured that when the light source 100 and the reflector 200 are in close contact, the light outlet of the light source 100 can be within the coverage area of the light inlet of the reflector 200, so that the light emitted from the light outlet of the light source 100 can completely enter the light inlet of the reflector 200.
[0025] Specifically, in this utility model, the reflector cup 200 has a conical structure, and a coating layer is covered on the surface of the reflector cup 200 to reflect the light 500 emitted by the light source 100, thereby changing the angle of the scattered light and achieving the first light control of the light 500; the light inlet of the reflector cup 200 is located at the small end of the conical structure, and the light outlet of the reflector cup 200 is located at the large end of the conical structure.
[0026] Specifically, in this invention, the outer contour of the convex lens 300 is circular. The side of the convex lens 300 near the reflector 200 is flat, and the side of the convex lens 300 near the Fresnel lens 400 is convex. The flat side of the convex lens 300 is the incident light surface, and the convex side is the exit light surface. The flat side of the convex lens 300 must completely cover the exit port of the reflector 200 to ensure the complete entry of the light ray 500. The light ray 500 emitted by the light source 100 is reflected by the reflector 400 and then enters the convex lens 300. The convex lens 300 can converge and integrate the light ray 500 reflected by the reflector 400 to perform a second light control on the light ray 500, thereby achieving comprehensive light control of the light ray 500.
[0027] Specifically, in this utility model, the outer contour of the Fresnel lens 400 is circular; for example... Figures 1 to 3 As shown, the side of the Fresnel lens 400 closest to the convex lens 300 is the incident light surface, and the side of the Fresnel lens 400 away from the convex lens 300 is the exiting light surface; the incident light surface of the Fresnel lens 400 can completely cover the convex surface of the convex lens 300. A beaded microstructure or textured structure is provided on the incident light surface of the Fresnel lens 400 to form a beaded microstructure surface or textured surface; Fresnel teeth are provided on the exiting light surface of the Fresnel lens 400, which are formed by multiple concentric ring structures on the exiting light surface of the Fresnel lens 400, and the grooves between each concentric ring structure can each serve as an independent lens. Through the Fresnel teeth on the exiting light surface, the Fresnel lens 400 can concentrate light to one point, forming a central focal point, adjusting the light into parallel light or focused light, and achieving precise control of the light output 500.
[0028] For specific implementations of the Fresnel lens 400, both the incident and exit surfaces can have various structures. For example, when the incident surface of the Fresnel lens 400 is textured, it can be formed into a textured plane through etching or frosting, i.e., an etched textured surface or a frosted textured surface. Alternatively, different compound eye dots can be set on the incident surface of the Fresnel lens 400 to form a bead-like microstructure surface; such as... Figure 4 As shown, the incident surface of the Fresnel lens 400 has multiple hexagonal compound eye dots arranged in an array, such as... Figure 5 As shown, the incident surface of the Fresnel lens 400 has four hexagonal compound eye dots arranged in an array. Other polygonal compound eye dots arranged in an array can also be used to form a polygonal compound eye microstructure surface; such as... Figure 6 As shown, multiple Fermat spiral structures can also be set on the light-incident surface of the Fresnel lens 400 to form a Fermat spiral compound eye microstructure surface.
[0029] When setting up the light source 100, reflector 200, convex lens 300 and Fresnel lens 400 in the zoom optical system, ensure that the light source 100, reflector 200, convex lens 300 and Fresnel lens 400 are all set coaxially, that is, the centers of the convex lens 300 and Fresnel lens 400 are both located on the central axis of the reflector 200.
[0030] Example
[0031] like Figure 2 As shown, light source 100 emits light ray 500, with a maximum scattering angle of 120°. Light ray 500 passes through reflector 200. A portion of the light ray with a larger scattering angle is scattered onto the inner wall of reflector 200, while the remaining light ray with a smaller scattering angle exits directly from the light outlet of reflector 200. The portion of the light ray with a larger scattering angle is reflected by reflector 200, reducing its scattering angle and achieving initial light control of this portion. The light ray after reflection by reflector 200 then passes through the light outlet of reflector 200 again... The light beam converges with the remaining light rays and passes through the convex lens 300. The convex lens 300 converges and integrates all the light rays, achieving a second comprehensive light control of the light ray 500. The maximum scattering angle of the light ray 500 will be reduced to about 60°. After two light control operations, the light ray 500 passes through the Fresnel lens 400. The bead microstructure or texture structure on the light-incident surface of the Fresnel lens 400, together with the Fresnel teeth on the light-outcident surface, performs a final angle control on the light ray 500, further reducing the emission angle of the light ray 500, so that the light ray 500 is finally emitted uniformly.
[0032] This utility model also discloses a lamp incorporating the aforementioned variable-focus optical system. Besides the light source 100, reflector 200, convex lens 300, and Fresnel lens 400 in the variable-focus optical system, the lamp also includes a focusing bracket. The light source 100, reflector 200, and convex lens 300 are all fixedly mounted on the focusing bracket, while the Fresnel lens 400 is movably mounted on the focusing bracket. The focusing bracket allows the Fresnel lens 400 to be translated relative to the convex lens 300, and the position of the Fresnel lens 400 is controlled to adjust the light spot and the angle of the light beam. This invention does not modify the structure of the focusing bracket; a mature focusing bracket from the prior art is sufficient.
Claims
1. A variable-focus optical system, characterized in that: The system includes a light source (100), a reflector (200), a convex lens (300), and a Fresnel lens (400) arranged sequentially. The light source (100) is close to the light inlet of the reflector (200), and the plane of the convex lens (300) is close to the light outlet of the reflector (200). The convex surface of the convex lens (300) faces the Fresnel lens (400). The side of the Fresnel lens (400) facing the convex lens (300) is the light inlet surface, and the side of the Fresnel lens (400) away from the convex lens (300) is the light outlet surface. The distance between the Fresnel lens (400) and the convex lens (300) is adjustable.
2. The variable focal length optical system as described in claim 1, characterized in that: The light-incident surface of the Fresnel lens (400) is a beaded microstructure surface or a textured surface, and the light-exit surface of the Fresnel lens (400) is a Fresnel surface.
3. The variable focal length optical system as described in claim 2, characterized in that: The light-incident surface of the Fresnel lens (400) is an etched textured surface or a frosted textured surface.
4. The variable focal length optical system as described in claim 2, characterized in that: The incident surface of the Fresnel lens (400) is a polygonal compound eye microstructure surface or a Fermat spiral compound eye microstructure surface.
5. The variable focal length optical system as described in claim 1, characterized in that: The outer contours of the convex lens (300) and the Fresnel lens (400) are both circular, and the reflector cup (200) has a conical structure; the centers of the convex lens (300) and the Fresnel lens (400) are located on the central axis of the reflector cup (200).
6. The variable focal length optical system as described in claim 1, characterized in that: The plane of the convex lens (300) covers the light outlet of the reflector cup (200), and the Fresnel lens (400) covers the convex surface of the convex lens (300).
7. The variable focal length optical system as described in claim 1, characterized in that: The light inlet of the reflector cup (200) covers the light emission range of the light source (100).
8. A lamp, characterized in that: The variable focus optical system as described in any one of claims 1 to 7 further includes a focusing bracket, wherein the light source (100), the reflector (200) and the convex lens (300) are fixedly mounted on the focusing bracket, and the Fresnel lens (400) is movably mounted on the focusing bracket and can be translated relative to the convex lens (300) through the focusing bracket.